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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 44 (1987), S. 187-193 
    ISSN: 1570-7458
    Keywords: Calosoma sycophanta ; Carabidae ; Coleoptera ; emigration ; gypsy moth ; Lymantria dispar ; spatial dispersion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé L'étude par capture-recapture de Calosoma sycophanta L. (Carabidae) a été effectuée dans deux parcelles de 4 ha en utilisant des pièges distribués sur une grille de 10 sur 10. Pendant la première année d'échantillonnage, Lymantria dispar L. (Lymantriidae) était abondant et les calosomes se sont reproduits, tandis que la seconde année les papillons étaient beaucoup moins nombreux. La distribution des larves de carabes a été examinée aussi pendant la première année sur l'une des stations, et celle des chenilles pendant les deux années avec des toiles d'emballage sur l'autre station. Les dispersions des adultes et larves de calosomes et des chenilles de Lymantria ont été calculées en utilisant la régression du logarithme naturel de la variance de l'échantillon sur le logarithme naturel de la moyenne (méthode de Taylor) et la régression de l'indice de Lloyd d'agrégation moyenne sur la moyenne (méthode d'Iwao). La méthode de Taylor a donné les résultats les plus logiques, et les pentes ont servi à mesurer le degré d'agrégation. Les recaptures de calosomes adultes ont été analysées par les méthodes de Fisher-Ford et Jolly-Seber, associées à la méthode de Jackson pour séparer survie et migration. De même, une nouvelle méthode pour déterminer directement la migration en découvrant combien d'insectes recapturés ont abandonné les microparcelles s'est révélée comme la plus cohérente avec le procédé Fisher-Ford-Jackson. La tendance à l'agrégation est plus forte chez les mâles (d'après la pente du logarithme de la moyenne par rapport au logarithm e de la variance de l'échantillon). La migration et le degré d'agrégation paraissent varier ensemble dans une station, tandis que dans l'autre une telle relation n'apparaît pas clairement. Les femelles malgré des taux de migration variés mais généralement faibles, n'ont jamais pr'esenté de tendance significative à l'agrégation. A l'opposé, les larves de calosomes et de Lymantria ont presenté des distributions agrégatives.
    Notes: Abstract Mark-release studies of Calosoma sycophanta L. (Carabidae) in two 40000 m2 areas were done using traps deployed in 10 by 10 grids. In both areas, gypsy moths, Lymantria dispar L. (Lymantriidae), were abundant the first but not the second year of sampling. The distribution of carabid larvae was also investigated in the first year at one of the sites and the distribution of gypsy moth larvae found under burlap bands determined for 2 years at the other site. Dispersions of beetles and prey were evaluated by Taylor's logarithmic meanvariance method and Iwao's mean-mean crowding method. Taylor's method gave the most consistent results, and the slopes of the regression lines were used to determine degree of clumping. To evaluate dispersal of adult beetles, recapture data were analysed using the Fisher-Ford and Jolly-Seber methods in conjunction with Jackson's method for separating survival and emigration. A new method for estimating emigration was found to be most consistent with the Fisher-Ford-Jackson procedure. The tendency of the beetles to aggregate (measured via Taylor's method) was generally highest for males. In one site, emigration and degree of aggregation for males appeared to vary together, while at the other site no relationship was evident. Females showed few tendencies to aggregate. Both beetle larvae and gypsy moth larvae had clumped distributions.
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  • 2
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    Entomologia experimentalis et applicata 45 (1987), S. 102-104 
    ISSN: 1570-7458
    Keywords: Coleoptera ; Carabidae ; Bembidion ; Trechus ; Agonum ; sex determination ; adhesion ; male setae ; tarsomere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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  • 3
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    Entomologia experimentalis et applicata 45 (1987), S. 23-27 
    ISSN: 1570-7458
    Keywords: Coléoptère ; Bruchidae ; Olfactométrie ; phéromone sexuelle ; plante hôte ; régulation de la réproduction ; Coleoptera ; Bruchidae ; olfactometer ; sex pheromone ; host plant ; reproductive regulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary In order to meet its sexual partner, Zabrotes subfasciatus must rely on the olfactory signals emitted either by the female or the male insect. The attractiveness of male and female odours were therefore studied and compared in an olfactometer. The behaviour of virgin and inseminated females and males, left in contact with the host plant's seeds or not, was studied in terms of the age of the imagos. In all cases examined, male odours did not attract female insects. Virgin females kept without seeds of the host plant did not attract males. On the other hand, the odour of virgin females left in contact with bean seeds significantly attracted virgin males. The females' attractive power varied according to their age: older females released a chemical cue that was more attractive for the males. Emission of the sex-pheromone stops after insemination of the females but begins again after a certain period of time. Results are discussed in terms of what is known on the reproductive regulation of this bruchid.
    Notes: Abstract Pour rechercher son partenaire sexuel Zabrotes subfasciatus doit utiliser les signaux olfactifs émis soit par les mâles ou par les femelles. Le pouvoir attractif de l'odeur des mâles et des femelles sont donc étudiés et comparés par olfactométrie. Le comportement de mâles et de femelles vierges et inséminées, mis en contact des graines de la plante hôte ou non, est observé en fonction de l'âge des imagos. En aucun cas, les odeurs des mâles n'exercent une attraction sur les femelles. Les femelles vierges en absence de graines de haricot (Phaseolus vulgaris) n'exercent pas d'attraction sur les mâles vierges. Par contre les odeurs des femelles vierges mises en contact avec les graines de haricot sont très attractives pour les mâles vierges et varie en fonction de l'âge: il est plus affirmé chez les femelles plus âgées. L'émission de la phéromone sexuelle est interrompue après l'insémination des femelles mais reprend au bout d'un certain temps après celle-ci.
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  • 4
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    Entomologia experimentalis et applicata 43 (1987), S. 193-201 
    ISSN: 1570-7458
    Keywords: Leptopilina boulardi ; Cynipidae ; Hymenoptera ; parasitoid ; Drosophila ; Diptera ; field egg laying strategy ; functional response ; switching
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Le concept de réponse optimale d'un parasite vis-à-vis de l'hôte le plus favorable pour son développement demeure surtout théorique et n'a pu être vérifié que dans les conditions de laboratoire. Nous avons montré que Drosophila melanogaster s'avère être, par rapport à D. simulans, l'hôte le plus favorable pour le développement du cynipide parasite Leptopilina boulardi. Une étude sur le terrain a démontré que ce parasite présente une réponse fonctionnelle densité dépendante vis-à-vis de D. melanogaster et non vis-à-vis de D. simulans, avec un effet de bascule. D'autre part, il s'avère que ce parasite exploite beaucoup mieux son hôte, en évitant le superparasitisme, ceci étant démontré au laboratoire et dans la nature. Enfin, il apparaît qu'il est capable d'allonger sa période de ponte lorsque cet hôte est rare, ce qui ne se produit pas avec D. simulans.
    Notes: Abstract The hypothesis of optimal host species selection predicts that when a parasitoid has the choice between two host species, it will choose the species thay gives the best survival chances for its progeny. We confirmed this hypothesis by laboratory experiments with Leptopilina boulardi Barb. et al., a cynipid parasitoid which prefers Drosophila melanogaster Meigen (the host species most suitable for parasitoid survival) above D. simulans Sturt. As far as fitness parameters are concerned, the fertility of L. boulardi is higher with D. melanogaster; the egg laying can be spread out over a long period when this host is relatively scarce. This does not occur with D. simulans in which parasitic oviposition stops soon when this host is not abundant. Investigations of this foraging strategy were done under more complex natural conditions. We found that L. boulardi has a type III functional response with D. melanogaster only; furthermore, it seems that a switching effect may exist with this host. Parasitoid females appear to distribute their eggs more regularly on D. melanogaster, thus avoiding superparasitism. This seems to be independent of the relative frequency of this host. However, superparasitism of D. simulans did occur more frequently when this host was scarce.
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  • 5
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    Entomologia experimentalis et applicata 43 (1987), S. 205-208 
    ISSN: 1570-7458
    Keywords: Coleoptera ; Chrysomelidae ; Diabrotica virgifera ; corn rootworms ; prehatch development ; posthatch development ; protandry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé L'observation, au laboratoire, pendant une période d'éclosion de dix jours, des oeufs de D. v. virgifera LeConte, a montré que les oeufs mâles prédominent les deux premiers jours d'éclosion, que les oeufs des deux sexes, avec des fréquences 0,5/0,5, ont éclos les troisième et quatrième jours, et que les oeufs éclos du cinquième au dixième jour étaient presque tous femelles. Globalement, les oeufs femelles ont éclos en moyenne 2,9 jours plus tard que les oeufs mâles. De plus, la durée du développement post-embryonnaire des femelles a demandé 1,8 jour en plus. Une éclosion plus tardive et un développement post-embryonnaire plus long ont entrainé une émergence des femelles en moyenne 4,7 jours après les mâles. La période d'émergence des adultes s'est étalée sur 14 jours; les mâles ayant dominé pendant les 5 premiers jours et les femelles pendant les 9 derniers. Les mâles de D. v. virgifera semblent avoir évolué vers la protandrie en acquerant, tant une diapause post-embryonnaire que des stades de développements larvaire et nymphal plus brefs.
    Notes: Abstract Laboratory tests with eggs of Diabrotica virgifera virgifera LeConte showed that during a 10-day hatching period, hatch of male eggs predominated on the first and second days, eggs of mixed sex, with ca. 1:1 ratio, hatched on the third and fourth days, and eggs hatching from the fifth to the tenth days were nearly all female. Overall, female eggs hatched a mean of 2.9 days later than male eggs. Not only did female eggs hatch later, but the time for posthatch development to the adult stage was 1.8 days longer for females. The later egg hatch and longer posthatch development for females resulted in female adults emerging a mean of 4.7 days later than male adults. Total adult emergence lasted 14 days; of this, males predominated during the first 5 days, and females predominated during the last 9 days. Males of D. v. virgifera appear to have evolved protandry (the tendency for males to emerge before females) by developing both a postdiapause embryonic stage and a combined larval and pupal stage of shorter duration.
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  • 6
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    Entomologia experimentalis et applicata 44 (1987), S. 15-21 
    ISSN: 1570-7458
    Keywords: Callosobruchus maculatus ; Coleoptera ; Bruchidae ; intraspecific competition ; oviposition strategies ; resource exploitation ; vibrations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Lors de la compétition, les larves réagissent l'une par rapport à l'autre, même lorsque leurs galeries sont séparées. L'une est inhibée, tandis que l'autre se comporte comme si elle était seule. Le signal provoquant ces réactions, qui peut traverser du papier métallique, est dû vraisemblablement aux vibrations de mastication des larves; ces dernières perçoivent ces signaux tout au long de leur vie active. La larve la plus âgée ne l'emporte pas obligatoirement, ce qui signifie que le signal indique plus que l'âge. Les conditions expérimentales peuvent inverser les réponses des unes et des autres, bien que la larve la plus âgée puisse souvent mourir de ces conditions anormales de compétition. L'avantage potentiel associé à l'inhibition du futur perdant est mis en évidence en collant ensemble des graines. Quand la larve dominante se nymphose, la larve inhibée recommence à s'alimenter et achève son développement. En ayant eu son alimentation interrompue et en restant dans une galerie superficielle, la larve inhibée évite les affrontements et peut se développer lorsque la larve dominante meurt ou se nymphose, puisque la galerie de la larve inhibée n'avait pas été sectionnée. La stratégie de ponte réduit la fréquence de la compétition en uniformisant la distribution des oeufs; elle augmente les chances de survie des larves vaincues avec l'addition des oeufs sur les graines les plus grosses quand les disponibilités sont limitées. L'étude de l'évolution de ces adaptations a été possible puisque, comme on le sait, C. maculatus est génétiquement polymorphe pour les caractères déterminant le comportement de ponte des femelles et la compétition larvaire.
    Notes: Abstract Larvae of the bean weevil C. maculatus feeding in a single bean apparently respond to vibrations from each other's chewing: one larva feeds normally, the other is inhibited. If the burrows of the larvae intersect, the inhibited larva dies. If the dominant larva pupates or dies without the burrows intersecting, the inhibited larvae then feeds and matures if enough food remains. Since females add second eggs to the largest beans after most beans carry a single egg, competition is most common in the largest available beans, precisely where inhibited larvae can benefit from avoiding a contest.
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  • 7
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    Entomologia experimentalis et applicata 44 (1987), S. 53-58 
    ISSN: 1570-7458
    Keywords: Tomicus piniperda ; Coleoptera ; Scolytidae ; host recognition ; host volatiles ; attraction ; low vigor trees ; attacked trees
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Der Anflug von Tomicus piniperda (L.) (Coleoptera: Scolytidae) an Kiefern in schlechtem oder besserem Gesundheitszustand, mit oder ohne vorherigen Befall, wurde mit Hilfe von Leimfallen untersucht. An Bäumen in schlechtem Zustand wurden etwas mehr Käfer gefangen als an Bäumen in besserem Gesundheitszustand. Das deutet auf Unterschiede in Geruchsreizen zwischen den beiden Klassen des Baumzustands hin. An Kiefern, die von T. piniperda befallen waren oder simulierte Einbohrungen (von Hand gebohrte Löcher) hatten, wurden viel mehr Käfer gefangen als an Kontrollbäumen ohne oder mit sehr geringem Befall. Der starke Anflug von Käfern an befallene Bäume wird gedeutet als Reaktion auf Duftstoffe des Wirts, die aus den Borkenkäfergängen abgegeben werden.
    Notes: Abstract The attraction of Tomicus piniperda (L.) (Coleoptera: Scolytidae) to Scots pine trees of low and higher vigor with and without previous attacks was monitored with sticky traps. Somewhat higher numbers of beetles were caught on low vigor trees than on trees of higher vigor, indicating differences in olfactory stimuly between the two classes of trees. Many more beetles were caught on trees attacked by T. piniperda and on trees with simulated bark beetle galleries (manually drilled holes) than on control trees with no or only a few attacks. The strong attraction of beetles to attacked trees is attributed to the beetles responding to host volatiles released from the galleries.
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  • 8
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    Journal of molecular evolution 24 (1987), S. 260-271 
    ISSN: 1432-1432
    Keywords: Mouse ; Rat ; Two-dimensional electrophoresis ; Quantitative variability of proteins ; Qualitative variability of proteins ; Protein classes ; Membrane proteins ; Organ-specific proteins ; Regulatory genes ; Speciation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Proteins of membranes and cytosols were extracted from the livers and brains of mice (inbred strain DBA/6J) and rats (inbred strain DA/Han) and separated by two-dimensional electrophoresis (2-DE). The 2-DE patterns were compared with regard to qualitative (spot position) and quantitative (spot intensity) characteristics of the proteins of these two species. The following results were obtained: (1) Brain had more (higher percentage) conservative proteins (proteins found in both mice and rats) than liver; (2) plasma membranes had more conservative proteins than the cytosols; (3) organ-unspecific proteins contained more conservative proteins than relatively organ-specific proteins; (4) the pattern of distribution of genetic variability among different classes of proteins represented by findings 1–3 was the same for the qualitative and quantative characteristics of the proteins; and (5) some observations indicated that quantitative variability occurred more frequently among proteins than did qualitative variability. Our conclusion is that regulatory sequences in the DNA (regulatory genes) are subjected to functional constraints that differ in strength among different classes of proteins by the same ratios as the constraints acting on the structural genes. The overall effect of the selective pressure is, however, less stringent for regulatory genes than for structural genes. The results obtained here by comparing two different species are very similar to previous results we obtained by studying different subspecies (inbred strains of the mouse). From this finding arises a new concept: the study of molecular evolution on the basis of different classes of proteins. Our results were compared with data from the literature that were obtained in part from studies on cultured cells. The comparison suggested that cultured cells have lost their tissue-specific proteins, and so generate predominantly extremely conservative proteins.
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  • 9
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    European journal of nutrition 26 (1987), S. 43-51 
    ISSN: 1436-6215
    Keywords: Dietary protein ; Vitamin A ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Zusammenfassung Es wurde der Einfluß von Qualität und Quantität von Nahrungsproteinen auf die Verteilung einer einzigen massiven Dosis von Vitamin A in verschiedenen Organen wachsender Wistar-Ratten untersucht. Die Untersuchungen wurden mit Casein- und Bengal-Gram-Diäten mit 20 % und 10 % Proteingehalt und auch mit radioaktiv markiertem Retinylacetat durchgeführt. Die Ergebnisse zeigen, daß die Leberspeicherung sowohl von Vitamin A aus der Nahrung als auch die einer einzigen starken Vitamin-A-Gabe (20 000 I.U.) stark herabgesetzt war bei Ratten, die nach der Bengal-Gram-Diät gefüttert wurden, verglichen mit Ratten, die auf Casein-Diät gesetzt waren. Im Gegensatz zur Leberspeicherung ist das Vitamin-A-Niveau im Plasma in allen Gruppen vergleichbar. Füttern niedriger Protein-Qualität reduzierte die Gewebeverteilung von [3H]-Retinylacetat sowohl bei Kontrollratten als auch bei solchen, denen eine massive Dosis Vitamin A gegeben wurde. Diese Untersuchung läßt vermuten, daß sowohl schlechte Qualität als auch unzureichende Mengen von Nahrungsproteinen nachteilige Einflüsse auf den Vitamin-A-Zustand wachsender Ratten haben.
    Notes: Summary The influence of the quality and the quantity of dietary proteins on the distribution of a single massive dose of vitamin A in various organs of growing Wistar strain rats has been studied by using casein and bengal gram diets at 20 % and 10 % protein levels. The distribution of [3H]-retinyl acetate in various tissues was also investigated in these dietary conditions. The results show that the hepatic storage of dietary as well as a single massive dose (20,000 I.U.) of vitamin A was profoundly decreased in the rats fed on bengal gram diets as compared to those fed on casein diets. Regardless of hepatic stores, the plasma vitamin A levels were comparable in all the groups. Feeding of low quality of protein reduced the tissue distribution of [3H]-retinyl acetate in control as well as rats given a massive dose of vitamin A. This study suggests that both the poor quality and the inadequate quantity of dietary protein are detrimental influences on the vitamin A status of the growing rats.
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  • 10
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    Development genes and evolution 184 (1978), S. 233-249 
    ISSN: 1432-041X
    Keywords: Tissue culture ; Muscles ; Metamorphosis ; Ecdysone ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The differentiation of muscles in primary cultures of cells fromDrosophila melanogaster embryos was investigated. In early cultures, and in the absence of exogenous ecdysone, two main classes of muscle were found. Comparison, by light and electron microscopy, of one of these classes (the “myotube” class) with muscles from third instar larvae shows that this class corresponds to the muscles of the body wall of the larva. When α- or β-ecdysone is added to the cultures, these undergo a number of metamorphic changes. Most of the larval muscles disappear, and two new types of muscle form. Ultrastructural and light microscopic examination of these two types indicates that they correspond to the two classes of skeletal muscle (fibrillar and tubular) found in adult flies.
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  • 11
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    Development genes and evolution 184 (1978), S. 273-283 
    ISSN: 1432-041X
    Keywords: Nervous system ; Development ; Imaginal discs ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The pathway of adult sensory nerves has been analysed in three experimental situations: (i) in flies with grossly abnormal thoracic morphology resulting from X-irradiation early during development, (ii) in flies which had been subjected to surgical operations late in the larval period, (iii) in homoeotic mutants. The results provide experimental support for a simple mechanism in which developing adult axons join the nearest larval nerve and are guided by it up to the central nervous system. In particular, experimental interference with normal development can result in nerves from different segments, or from dorsal and ventral appendages, joining each other and entering the central nervous system together.
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  • 12
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    Development genes and evolution 196 (1987), S. 372-375 
    ISSN: 1432-041X
    Keywords: Pattern formation ; Morphogenesis ; Drosophila ; Growth ; Imaginal disc
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A comparison of the morphogenetic maps of the notum anlage of Drosophila melanogaster derived from the gynandromorph data and mosaics induced by somatic crossing-over during the first instar larval stage revealed that practically no major morphogenetic movements occur in the development of the anlage between the blastoderm and first instar larval stages and the adult stage. By comparing the morphogenetic map derived from gynandromorphs and the fate map derived from data on the transplantation of fragments of the mature wing imaginal disc, it was observed that no major morphogenetic movements occur in the notum anlage between the stages of the allocation of the disc and the mature disc. The results are consistent with the observations of other authors concerning the larval development of eye-antenna, wing and leg discs.
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  • 13
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    Development genes and evolution 196 (1987), S. 434-444 
    ISSN: 1432-041X
    Keywords: Morphogenesis ; Cell Surface ; 20-Hydroxyecdysone ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Polyclonal antibodies (anti-P116 and anti-P93) specific for two different hormone-dependent cell surface glycoproteins (P116 and P93) from Drosophila S3 cells have been produced. Anti-P116 and anti-P93 each immunoprecipitate substantially more of P116 and P93, respectively, from extracts of iodinated hormone-treated S3 cells compared to controls. Both antigens are present in control and 20-hydroxyecdysone treated imaginal discs, although apparent increases in antigen content are associated with hormone treatment. Immunofluorescent staining of whole discs with anti-P116 and anti-P93 reveals increased amounts of both antigens at the surface of hormone-treated discs compared to controls. Both antibodies were used to characterize the expression of their respective antigens during embryonic development, and both antibodies were found to recognize in embryos a third developmentally-regulated antigen with a relative mobility of approximately 220000. Our results indicate, at least in the case of P116 and P93, that 20-hydroxyecdysone-dependent cell surface antigens in imaginal discs may be regulated both by increasing the amounts of constitutively present proteins, and possibly through biochemical modifications, altering the localization of these proteins from a cytoplasmic to a cell surface domain.
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  • 14
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    Development genes and evolution 196 (1987), S. 69-77 
    ISSN: 1432-041X
    Keywords: Neurogenesis ; Drosophila ; Neuronal differentiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The stereotyped segmental and dorso-ventral organization of the peripheral nervous system (PNS) of Drosophila embryos allows the identification of all the neurons in the body wall. Distinct classes of neurons are distinguishable according to their location, the targets they innervate, the particular shape of their dendrites and their cell size. Those neurons innervating external sensory structures (es) and chordotonal organs (ch) have single dendrites and have been previously described (Ghysen et al. 1986; Dambly-Chaudiere and Ghysen 1986; Campos-Ortega and Hartenstein 1985). We describe here the identity and morphological features of three other classes of neurons in the body segments which have multiple dendrites (md neurons): 1) neurons that give rise to elaborate dendritic arborisations (da neurons); 2) neurons that have bipolar dendrites (bd neurons); 3) neurons that arborize around particular tracheal branches (td neurons). The thoracic hemisegment (T2 and T3) contains 13 da, one bd, one td, 21 es and four ch neurons; the abdominal hemisegment (A1 to A7) contains 14 da, three bd, three td, 15 es and eight ch neurons. The arrangement of the segmented peripheral neurons is highly invariant and provides a favorable assay system for the genetic analysis of neurodevelopment.
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  • 15
    ISSN: 1432-041X
    Keywords: Imaginal disc ; Evagination ; Surface peptides ; Radiolabeling ; Hormone depending ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Unevaginated and evaginated Drosophila imaginal discs were surface-labeled with 125I. Relative labeling was greater in eleven peptides and lower in three peptides of evaginated discs compared to unevaginated discs. These results are compared to the effects of 20-hydroxyecdysone (20-HOE) on metabolic labeling of membrane proteins fractionated from imaginal discs, and on cell surface labeling of a hormone-responsive Drosophila tissue culture line. A group of 35S-methionine labeled membrane fraction peptides whose metabolic labeling is 20-HOE dependent have isoelectric points and apparent molecular weights very similar to those of a group of proteins only labeled in iodinated evaginated discs, supporting the conclusion that these are hormone-dependent, cell surface proteins (Rickoll and Fristrom 1983). Based upon two-dimensional gel electrophoretic and immunological criteria three of the proteins showing increased labeling in evaginated discs are related to three proteins induced by 20-HOE in tissue culture cells. Two different subsets of radiolabeled peptides were observed in the imaginal discs based upon detergent solubility. Some of the proteins which are soluble in NP-40 plus urea but insoluble in NP-40 alone may be localized in the basal lamina of the imaginal discs, a structure which labels heavily with 125I and is lacking in tissue culture cells. In discs, the majority of hormone-dependent changes in radiolabeled peptides were seen in the fraction solubilized by NP-40 and urea with a sulfhydryl reducing agent, while in tissue culture cells, the majority of differences is seen in the fraction solubilized by NP-40 only. We speculate that these proteins may be involved in similar processes, e.g., cell rearrangement, that occur during both disc morphogenesis and 20-HOE induced aggregation in tissue culture cells.
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    Cellular and molecular life sciences 43 (1987), S. 445-446 
    ISSN: 1420-9071
    Keywords: Cell survival ; photoreactivation ; insect cell ; Drosophila ; colony formation ; DNA repair ; ultraviolet radiation
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    Topics: Biology , Medicine
    Notes: Summary Cell survival and photoreactivation of 254 nm ultraviolet (UV) light damage in a wild typeDrosophila cell line was assayed by colony formation in liquid medium. Fo, Fq, and extrapolation number for the exponential portion of survival curves are 21 J/m2, 3.6 J/m2, and 1.5 for non-photoreactivated cells and 110 J/m2, 11.2 J/m2, and 1.3 for those exposed to photoreactivating light. Maximal photoreactivation occurs at the 100 J/m2 region of the curve. At 10 and 50% survival, 75–80% of the UV damage was photoreactivable.
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  • 17
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    Cellular and molecular life sciences 43 (1987), S. 458-460 
    ISSN: 1420-9071
    Keywords: Defensive secretions ; glands ; Chrysomelidae ; Coleoptera ; phenylethanol ; linalool ; 6-methyl-5-hepten-2-one ; 6-methyl-5-hepten-2-ol ; 2-hexenal ; chemotaxonomy
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    Topics: Biology , Medicine
    Notes: Summary The leaf beetle larva ofGonioctena (Phytodecta) viminalis L. has been shown to produce five volatile constituents within its paired abdominal defensive gland reservoirs. It is the first time that these compounds have been reported to occur in coleopteran defensive glands (linalool, phenylethanol) and Chrysomelidae larvae (6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol, 2-hexenal). In addition to the gross morphology of theGonioctena gland and its discharge behavior, the natural products found are discussed in terms of chemotaxonomy.
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  • 18
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    Cellular and molecular life sciences 43 (1987), S. 460-462 
    ISSN: 1420-9071
    Keywords: Biosynthesis ; cardenolides ; Coleoptera ; chrysomelid beetles ; [23-14C]-cholesterol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Labeling experiments have shown that the chrysomelid beetleChrysolina coerulans is able to biosynthesize its own defensive cardenolides from cholesterol, via a pathway involving a C21 intermediate, as in plants.
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  • 19
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    Development genes and evolution 184 (1978), S. 155-170 
    ISSN: 1432-041X
    Keywords: Developmental restrictions ; Compound eye ; Pattern formation ; Genetic mosaics ; Drosophila
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    Topics: Biology
    Notes: Summary Five regions of the compound eye have been found to be preferential boundaries for clones of labelledMinute + cells, and to act restrictively on the growth of cell clones after a given developmental stage. One of these regions is topographically related to the line of pattern inversion existing at the level of the equator. The results of experiments showing independency of origin of restriction lines and line of pattern inversion are reported.
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  • 20
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    Development genes and evolution 196 (1987), S. 191-201 
    ISSN: 1432-041X
    Keywords: Wing imaginal disc ; Tissue culture ; Metamorphosis ; Drosophila
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    Topics: Biology
    Notes: Summary We have examined the metamorphosis of the wing imaginal disc of Drosophila during culture in vitro in the continuous presence of 20-hydroxy ecdysone (0.1 μg/ ml). We find that the sequence of cellular changes in the wing blade during culture closely match those occurring in situ, involving two periods at which the dorsal and ventral surfaces are joined only by cell processes containing trans-alar microtubule arrays. Good pupal and imaginal cuticle secretion is found in this system.
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  • 21
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    Development genes and evolution 196 (1987), S. 222-230 
    ISSN: 1432-041X
    Keywords: Mesodermal cell lineages ; Cell transplantations ; Embryogenesis ; Drosophila
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    Topics: Biology
    Notes: Summary We describe the results of cell transplantation experiments performed to investigate mesodermal lineages in Drosophila melanogaster, particularly the lineages of the somatic muscles, the visceral muscles and the fat body. Cells to be transplanted were labelled by injecting a mixture of horseradish peroxidase (HRP) and fluorescein-dextran (FITC) in wild-type embryos at the syncytial blastoderm stage. For transplantation cells were removed from the ventral furrow, 8–12 min after the start of gastrulation, and individually transplanted into homotopic or heterotopic locations of unlabelled wild-type hosts of the same age. HRP labelling in the resulting cell clones was demonstrated histochemically in the fully developed embryo; histotypes could be distinguished without ambiguity. Mesodermal cells were already found to be committed to mesodermal fates at the time of transplantation. They developed only into mesodermal derivatives and did not integrate in non-mesodermal organs upon heterotopical transplantation. No evidence was found for commitment to any particular mesodermal organ at the time of transplantation. The majority of somatic muscle clones contributed cells to only one segment. However, clones were not infrequently distributed through two or even three segments. Clones of fat body cells were generally restricted to a small region. However, cells of clones of visceral musculature were widely distributed. With respect to the proliferative abilities of transplanted cells the clones were difficult to interpret due to the syncytial character of the somatic musculature and the fact that the organization of the other organs is poorly understood. Evidence from histological observations of developing normal embryos indicates only three mitoses for mesodermal cells. Clones larger than seven cells were not found when embryos were fixed previous to germ-band shortening; larger clones were found in the fat body and visceral musculature after fixing the embryos at the end of organogenesis. Quantitative considerations suggest that a few mesodermal cells might perform more than three mitoses.
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  • 22
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    Development genes and evolution 196 (1987), S. 511-521 
    ISSN: 1432-041X
    Keywords: Segmentation defects, ether-induced ; Drosophila ; Phenocopies
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    Topics: Biology
    Notes: Summary Drosophila embryos, exposed to ether between 1 and 4 h after oviposition, develop defects ranging from the complete lack of segmentation to isolated gaps in single segments. Between these extremes are varying extents of incomplete and abnormal segmentation. On the basis of both their temporal and spatial characteristics, five major phenotype classes may be distinguished: headless — unsegmented or incompletely segmented anteriorly; gap — interruptions of segmentation not obviously periodic; alternating segment gaps — interruptions with double segment periodicities; fused segments; and short segments — truncations with single segment periodicities. Many defects resemble known mutant phenotypes. The disturbances in segmentation are predominantly global and frequently accompanied by alterations in segment specification, such that the segments obtained show no resemblance to the normal homologues. These features, together with the distinctive spatiotemporal characteristics of the defects, all point to segmentation as a dynamic process. The regular spacing of the segments and the fact that the entire range of defects is inducible by ether are further consistent with the hypothesis that at least part of the segmentation process may consist of physicochemical reactions coordinated over the whole body. The relationship between our data and data from genetic and other analyses are briefly discussed.
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  • 23
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    Development genes and evolution 184 (1978), S. 75-82 
    ISSN: 1432-041X
    Keywords: Egg shape ; Pole cell transplantation ; Sterility ; Drosophila
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    Topics: Biology
    Notes: Summary Females homozygous for a newly isolated mutation induced by ethyl methane sulphonate,fs(1)K10, lay abnormally shaped eggs in which the dorsal appendages of the chorion are enlarged and fused ventrally. The eggs are usually not fertilized and development is never normal beyond the blastoderm stage. The mutant was mapped to the tip of the X-chromosome with a meiotic position of 1–0.5 and a cytological location between 2B17 and 3A3. Using germ line mosaics constructed by transplantation of pole cells, it was shown that the abnormal morphology and the sterility are obtained only when the germ line is homozygous for the mutant.
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  • 24
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    Development genes and evolution 196 (1987), S. 12-15 
    ISSN: 1432-041X
    Keywords: Gene expression ; Drosophila ; Mitochondria ; Temperature sensitivity
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    Topics: Biology
    Notes: Summary The fine structure of the indirect flight muscles was studied by electron microscopy in the following Notch locus mutants of Drosophila melanogaster reared at 18° C or 29° C for 6 days after eclosion: Ax 16172/Ax16172, Ax28/ Ax28, l(1)Nts1/l(1)Nts1,l(1)Nts1/Y and in wild-type controls. The flies were raised up to eclosion at 25° C or 18° C. It was observed that the l(1)Nts1 flies gradually became flightless within a few days if reared at 29° C as adults, and gross changes in the fine structure of the flight muscles were also observed in flies of this genotype. Peripheral myofilaments of myofibrils were disarranged and the mitochondria diminutive. At 18° C the flight muscles remained normal. In all of the Abruptex (Ax) combinations the flight muscles remained similar to the wild-type controls at both 18° C and 29° C, i.e. they were normal. The results suggest that the Notch gene is active in adult flies in addition to its activity during embryonic, larval and pupal stages, and is directly or indirectly involved in the adult development of the muscle tissue.
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  • 25
    ISSN: 1432-041X
    Keywords: Drosophila ; Spermatogenesis ; Y chromosome ; Lampbrush loops ; Sex determination ; Maternal effects
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    Notes: Summary The Y chromosome of Drosophila hydei carries information that is necessary for the development of the spermatozoa. In primary spermatocytes Y chromosomal genes become active: five of the male fertility factors form giant lampbrush loops. Our prior work indicated interactions between the Y chromosomal genes and autosomal loci. It is of interest to identify loci regulating the activity of the Y chromosomal genes. We, therefore, screened a total of about 14,000 chromosomes (X, 2, 3 and 4) for mutations that interfere with the expression of the lampbrush loops. Two mutations with substantial effects on the loop morphology were recovered. One of them, a recessive male sterile mutation (ms (3) 5) on chromosome 3, is described in this paper. Its homozygous state results in a complete absence of all Y chromosomal lampbrush loops at 26° C; at 18° C the loops are formed. Temperature shifts with homozygous males indicate that the function early during the spermatogonial stage is crucial for the development of lampbrush loops in the primary spermatocyte. Meiosis is entirely absent in the male, but normal in females. Females homozygous for ms (3) 5 display a maternal effect, which reduces the viability and fertility of homozygous daughters and produces sons with signs of intersexuality. Linkage studies indicated that the effect on the male germ line and the maternal effects cannot be separated and may hence be induced by a single gene.
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  • 26
    ISSN: 1432-041X
    Keywords: Drosophila ; Collagen ; Haemocytes ; Basement membranes
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    Notes: Summary We report a direct examination of the expression of one collagen gene (DCg1) during Drosophila melanogaster metamorphosis, based on data from in situ hybridization. The transcripts of this gene, thought to encode a basement membrane type IV collagen, are mainly accumulated during ecdysis in wandering haemocytes. Our results demonstrate that haemocytes contribute to extracellular matrix deposition and seem to perform a fibroblastic function during Drosophila development.
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  • 27
    ISSN: 1432-041X
    Keywords: Drosophila ; Homoetic ; Mutational analysis ; Transformation ; Distal disc structures
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    Notes: Summary A gene Brista has been identified in chromosome 2R, in the region 60D11-E4, in which mutations cause homoeotic transformation of distal antennal structures to distal leg derivatives, and in which certain alleles also lead to upsets in the formation of distal elements of the legs. This gene is haploinsufficient for the homoeotic phenotype. Several putative null and two hypomorphic alleles have been recovered. The effects of exposure to the non-permissive temperature of a temperature-sensitive allele are cummulative and depend upon the length of the exposure during the period of antennal cell proliferation. It is suggested that this gene contributes to the stability of the state of determination in distal domain of the antennal and leg discs, and its relationship to other genes with similar mutant phenotype is discussed.
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    Development genes and evolution 196 (1987), S. 141-157 
    ISSN: 1432-041X
    Keywords: Drosophila ; Blastoderm fate-map ; Tail segmentation ; Larval cuticle
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    Topics: Biology
    Notes: Summary The segmental organisation of the tail region in the embryo of Drosophila melanogaster, which is defined here as the epidermal region posterior to the boundary between abdominal segments A7 and A8, has been investigated by means of ultraviolet (UV) laser fate-mapping and phenotypic analysis of embryonic mutants that alter the segmental pattern of the larval cuticle. Wild-type embryos were irradiated in the presumptive tail region with a UV- laser microbeam of 20 μm diameter at the blastoderm stage. The ensuing defects were scored in the cuticle pattern of the tail region of the first-instar larva, which is described in detail in this paper. The spatial distribution of defect frequencies was used to construct a blastoderm fate-map of the cuticle structures of the larval tail region. The segmental origin of the larval tail structures was inferred from the phenotypic analysis of segmentation and homoeotic mutants, which revealed pattern repetition throughout the embryonic tail region corresponding to four segment anlagen, A8 to A11, and a non-segmental telson. These data enabled the transformation of the blastoderm fate-map of cuticle structures into a map of tail segment anlagen. The tail anlage occupies about 10% of the egg length (EL), bounded by segment A7 anteriorly at 20% EL and by the proctodaeum posteriorly at 10% EL, as measured from the posterior pole. The anlagen of segments A8 and A9 appear to be narrow dorso-ventral strips of blastoderm cells similar to the anlagen of the trunk segments, whereas the anlagen of A10 and A11 are smaller and produce fewer pattern elements. The telson is represented in the cuticle by the tuft which derives from a very dorsal posterior position. The antero-posterior axis of the entire tail anlage appears curved upward posteriorly. Differences in the mode of development between tail and trunk segments are discussed, as are similarities of larval and imaginal tail development in Drosophila. Comparison with tail development in other insects suggests that, during evolution, the transition from semi-long-germ to long-germ development modified the organisation of the tail region without affecting its primary subdivision into metameric units.
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    Development genes and evolution 196 (1987), S. 101-112 
    ISSN: 1432-041X
    Keywords: Peripheral nervous system ; Compartments ; Segmentation mutants ; Drosophila
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    Topics: Biology
    Notes: Summary The peripheral nervous system of embryos homozygous for prd, ftz, en and bxd was examined for defects and transformations in the segment-specific pattern of sensilla and peripheral nerves. This analysis permitted me to assign a distinct subset of sensilla to any of the three genetically and morphologically defined compartments s, a and p of each segment. In the wild-type embryonic segments, sensory axons deriving from sensilla of different compartments form a part of the common peripheral nerves. In the composite segments of prd and ftz mutant embryos, subsets of sensilla of two neighbouring segments are combined. Nevertheless, the axons of sensilla of different segmental identity are able to fasciculate and to form afferent nerves, which connect in an apparently normal fashion to the central nervous system. It is concluded that in the Drosophila embryo compartmental and segmental identity of sensory organs has no influence on the trajectories of sensory axons.
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  • 30
    ISSN: 1432-041X
    Keywords: Drosophila ; Dorsalizing mutant ; Phenotypic rescue ; Poly(A)+ RNA ; Cytoplasm
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    Notes: Summary spätzle (spz), a maternal effect gene of Drosophila, is involved in the establishment of the dorso-ventral axis during embryogenesis. Eggs from females lacking the spz gene product develop into completely dorsalized embryos, i.e. the ventral and lateral pattern elements fail to develop. Upon injection of either cytoplasm or poly(A)+ RNA from early wild-type embryos, spz embryos develop lateral pattern elements represented by Filzkörper and in the case of injected cytoplasm additional ventral pattern elements represented by ventral setae. Wild-type cytoplasm retains the rescuing activity longer than the poly(A)+ RNA fraction does, and cytoplasm is always more effective in provoking the rescue than poly(A)+ RNA. Mosaic females containing spz germ cells surrounded by spz + tissues were generated by pole cell transplantations; a mutant genotype in the germ cells is sufficient to produce all aspects of the spz mutant phenotype, suggesting that the maternal source of spz gene product is the germ line.
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    Development genes and evolution 185 (1978), S. 249-270 
    ISSN: 1432-041X
    Keywords: Drosophila ; Gynandromorphs ; Cell lineage ; Sexual dimorphism ; Genital discs
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    Topics: Biology
    Notes: Summary The embryonic organization of the sexually dimorphic genital disc was studied in genetic mosaics resulting (a) from early loss of a chromosome or (b) from mitotic recombination. (a) Early Loss of a Chromosome. Three types of mosaics were produced — purely female mosaics, purely male mosaics, and gynandromorphs. They show that the genital disc arises from a group of cells in the ventral region of the embryo somewhat larger than that giving rise to a single foreleg (Table 2). Within this group of cells three regions can be distinguished that are present in both sexes: an anterior, a medial, and a posterior one, with distances of only 3–4 sturts between adjacent regions. The anterior region gives rise to the female genitalia, the medial region to the male genitalia, and the posterior region forms the analia of both sexes and the parovaria of the female (Figs. 2 and 3). The relative positions of the three regions were deduced from sturt distances (Tables 1 and 5), and from frequencies of mosaicism (Table 2). (b) Mitotic recombination was induced at the blastoderm stage in order to produce twin spots in the external genitalia and analia of purely male and female flies. Clone sizes indicate that these structures arise from a small number of precursor cells (Table 4). Clones overlapped right and left sides, but no clones were found extending over analia and genitalia. However, within either the analia or the genitalia of each sex, no clonal restrictions could be observed, and the clones comprised structures that were up to 12 sturts apart. A comparison of clone sizes and sturt distances in the foreleg and in the genital disc indicates that equal gynandromorph distances involve equal numbers of cells in different regions on the ellipsoid egg (Fig. 5). The results obtained from all mosaics provide a consistent picture of the embryonic organization of the genital disc. This becomes apparent in the summarized fate maps (Fig. 4), where the map derived from normal gynandromorphs can be produced by a simple superposition of the male and the female maps. The data are also discussed with respect to mechanisms of sexual differentiation in the genital disc.
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    Development genes and evolution 185 (1978), S. 271-292 
    ISSN: 1432-041X
    Keywords: Homeotic mutations ; Imaginal disc ; Positional Information ; Drosophila
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    Topics: Biology
    Notes: Summary Mutations of the bithorax complex result in segmental transformations in the thorax and abdomen ofDrosophila. The haltere discs from larvae homozygous forbx 3 orpbx are transformed so that the discs contain cells that will produce wing cuticle as well as cells that produce haltere cuticle. The pattern regulation behavior of these discs has been examined. The fate maps of the two discs were established, and then the regulative behavior of a number of fragments from both types of mutant discs was established by culturing the fragments in vivo prior to metamorphosis. The most important conclusion from this work is that the cells producing, haltere cuticle and wing cuticle within the same disc share the same positional information and that they communicate during pattern regulation.
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    Cellular and molecular life sciences 43 (1987), S. 213-215 
    ISSN: 1420-9071
    Keywords: Drosophila ; reproductive behavior ; oviposition ; pheromones
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    Topics: Biology , Medicine
    Notes: Summary A residual influence of males and females on oviposition has been examined in 7 drosophilids. There was evidence for oviposition deterrence inDrosophila funebris, with males as well as females producing the inhibitory effect. In contrast, male residues stimulated oviposition inZaprionus tuberculatus. Male residues also stimulated oviposition and appeared to serve as an aggregation cue inD. melanogaster.
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    Cellular and molecular life sciences 43 (1987), S. 931-933 
    ISSN: 1420-9071
    Keywords: Hyperthermia ; gamma ray ; crossing-over ; Drosophila ; repair mutant
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    Topics: Biology , Medicine
    Notes: Summary Hyperthermia of 1 h at 38°C did increase gamma-ray induced crossing-over in meiotic cells of male larvae and adults. However, there was considerably less effect of the heat treatment upon radiation induced crossing-over (a chromosome breakage event) in an excision repair mutanty mei-9 a.
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    Calcified tissue international 25 (1978), S. 75-83 
    ISSN: 1432-0827
    Keywords: Rat ; Fluorosis ; Enamel ; Scanning electron microscopy ; Low temperature incineration
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    Topics: Biology , Medicine , Physics
    Notes: Summary Sixteen 58-day-old male rats of Wistar strain, with a mean body weight of 179 g, were divided into two equal groups. Each group of eight animals was maintained for 70 days on drinking water, ad lib., containing no fluorine (control group) and 100 ppm of fluorine (experimental group). All specimens examined were obtained from the incisal portions of the incisors. The following types of enamel specimens were prepared for scanning electron microscopy: (1) acid-etched specimens; (2) acid-etched specimens followed by low temperature microincineration; and (3) fractured specimens. The enamel formed during high fluoride exposure showed marked hypocalcification, that is, the crystallite density in the prism core and interprismatic region was lower than that of control animals. The organic substances appeared to increase in these regions. These changes were prominent in the outer and middle enamel layers. Such changes following fluoride administration appear to indicate an inhibition of enamel maturation, that is, an inhibition of the mineral deposition and/or an inhibition of organic matrix withdrawal.
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  • 36
    ISSN: 1432-1939
    Keywords: Drosophila ; Polymorphism ; Stenocereus ; Host-plant-shift ; Developmental homeostasis
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    Topics: Biology
    Notes: Summary Chromosomally polymorphic populations of Drosophila mojavensis from Baja California feed and breed on agria cactus, Stenocereus gummosus; whereas, monomorphic Arizona populations are associated exclusively with organ pipe cactus, S. thurberi. The effects of this host plant shift in expanding the kinds of feeding and breeding sites were assessed by manipulating larval density and recording differences in egg to adult development time and viability, and adult thorax size in both populations on artificially rotted substrates of both cactus species. Older agria rots increased development time but had no effect on viability. Organ pipe rots were qualitatively poorer substrates than agria rots for both monomorphic and polymorphic populations of D. mojavensis, especially at higher larval densities causing longer egg to adult development times, lower viabilities, and smaller thorax sizes than agria. The Baja population expressed shorter development times, higher viabilities, and smaller thorax sizes than the Arizona population on both cactus substrates. No evidence for cactus host race formation was found. The Baja population was less sensitive to increasing larval densities for all fitness characters studied on both cactus substrates indicating greater developmental homeostasis than in the monomorphic Arizona population. These data support the hypothesized central-marginal population structure within this species coincident with the distribution of host plants and lend insight into the process of adaptive divergence at different life history stages caused by host plant shifts.
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  • 37
    ISSN: 1573-4927
    Keywords: Drosophila ; hemolymph proteins ; gene regulation
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Three of the major protein species present in the hemolymph of Drosophila melanogaster larvae just prior to pupation are absent from second instar larvae but accumulate rapidly during the third instar. This article describes the purification and characterization of one of these, larval serum protein (LSP) 2, using an immunological assay. It is a homohexamer of molecular weight about 450,000, with a polypeptide molecular weight of 78,000–83,000. Fast and slow electrophoretic variants of this protein map between the markers vin and gs, at 36–37 on chromosome 3.
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    Biochemical genetics 16 (1978), S. 927-940 
    ISSN: 1573-4927
    Keywords: trehalase ; Drosophila ; segmental aneuploidy
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Only one molecular form of trehalase (E.C. 3.2.1.28) was detectable in adult Drosophila melanogaster by polyacrylamide gel electrophoresis and isoelectric focusing. An examination of duplication- and deletion-bearing aneuploids exhibiting do sage sensitivity indicated that the enzyme is encoded by a gene, Treh +, located between 55B and 55E of the second chromosome. The tissue-specific soluble and particulate forms of trehalase appear to be manifestations of a single protein encoded by a single gene.
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  • 39
    ISSN: 1573-4927
    Keywords: mutagenesis ; alcohol dehydrogenase ; formaldehyde ; Drosophila ; deletions
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Adh fn23 andAdh fn24 are two formaldehyde-induced, homozygous-viable, alcohol dehydrogenase-null mutants that bear lesions in the gene tht codes for the alcohol dehydrogenase (ADH; EC 1.1.1.1) ofDrosophila melanogaster. Adh fn23 contains a 34-base pair deletion in the C-terminal coding region of the alcohol dehydrogenase structural gene. By immunological and molecular analysis, we show that the deletion shifts the translation reading frame and results in a prematurely truncated polypeptide product (10 amino acids shorter than wild type) that cross-reacts with antibody raised against ADH. The steady-state level of alcohol dehydrogenase mRNA present in this mutant is close (97%) to that in the wild type, but the steady-state level of alcohol dehydrogenase-like protein is 50% lower. Moreover, the rate of alcohol dehydrogenase synthesis inAdh fn23 flies is reduced to 60% of that found in the wild type. Hence both the rate of synthesis and the rate of degradation of alcohol dehydrogenase are affected. In contrast,Adh fn24 which contains an 11-base pair deletion in the N-terminal coding region of the ADH gene, synthesizes no immunodetectable protein, and the amount of alcohol dehydrogenase mRNA is less than half that of wild-type flies. As withAdh fn23, the deletion inAdh fn24 results in a change in the reading frame. UnlikeAdh fn23, however, nucleic acid sequence data indicate that polypeptide chain elongation can proceed for a considerable distance (over 130 amino acids) beyond the deletion. Based upon antigenic binding-site predictions, the resultant aberrant protein (projected 195 amino acids in length) would share few antigenic sites with the alcohol dehydrogenase from the wild type, which may account for the lack of immunoprecipitable material in this mutant. The contrasting effects these two deletions have on theDrosophila ADH mRNA levels and ADH protein levels are discussed.
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  • 40
    ISSN: 1573-4927
    Keywords: pyrimidine biosynthesis ; Drosophila ; rudimentary
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Glutamine-dependent CPSase, ATCase, and DHOase from Drosophila, the first three enzymes in pyrimidine biosynthesis, show coordinate variation in activity throughout development. The three activities were highest in first instar larvae and decreased as development proceeded. The three activities cosediment in sucrose gradients as a single peak with a relative sedimentation coefficient of approximately 30S. CPSase, ATCase, and DHOase copurify during (NH4) 2SO4 fractionation and during DEAE-cellulose and hydroxylapatite chromatography.
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    Biochemical genetics 16 (1978), S. 485-507 
    ISSN: 1573-4927
    Keywords: sorbitol dehydrogenases ; polyols ; Drosophila ; spermatogenesis
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract It has been shown that crude extracts of Drosophila melanogaster adults contain three distinctly different enzymes which catalyze the oxidation of d-sorbitol into d-fructose. These include (1) a soluble NAD-dependent sorbitol dehydrogenase (NAD-SoDHs), (2) a mitochondrial NAD-dependent sorbitol dehydrogenase (NAD-SoDHm), and (3) a soluble NADP-dependent sorbitol dehydrogenase (NADP-SoDH). Developmental studies have shown that the activities of all three of these enzymes are lowest during the larval stages while highest levels are seen during or shortly prior to the adult period. With respect to NAD-SoDHs, studies of tissue distribution in adults have shown that highest activity is associated with thoracic musculature in both sexes and with organs of the male reproductive system. The developmental profile of this enzyme reveals a significant increase in activity at between 40 and 60 hr after hatching. This time interval corresponds closely to that during which the paternally derived NAD-SoDHs gene is expressed. An additional increase in activity is seen in male pupae at 160 hr and in female adults at 210 hr. The rapid increase in males takes place immediately following the developmental period during which the testes attach to their respective duct systems. NADP-SoDH activity is concentrated among organs of the thorax and abdomen in both sexes. Males show significantly higher levels of this enzyme during the late pupal and early adult periods. In contrast to the patterns of distribution seen for NAD-SoDHs and NADP-SoDH, 91–92% of the total NAD-SoDHm activity in adults is localized to the thoracic musculature. The developmental profile of this enzyme reveals a significant increase in activity during the late pupal and early adult periods, when flight muscle mitochondria are known to be proliferating and undergoing structural maturation.
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  • 42
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    Biochemical genetics 16 (1978), S. 509-523 
    ISSN: 1573-4927
    Keywords: alcohol dehydrogenase ; enzyme levels ; gene regulation ; Drosophila
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    Notes: Abstract Among the progeny of Drosophila flies heterozygous for two noncomplementing Adh-negative alleles, two individuals were found that had recovered appreciable alcohol dehydrogenase activity, thereby surviving the ethanol medium used as a screen. The most likely explanation is that these Adh-positive flies are the product of intracistronic recombination within the Adh locus. Judging by the distribution of outside markers, one of the crossovers would have been a conventional reciprocal exchange while the other appears to have been an instance of nonreciprocal recombination. The enzymes produced in strains derived from the original survivors can be easily distinguished from wild-type enzymes ADH-S and ADH-F on the basis of their sensitivity to denaturing agents. None of various physical and catalytic properties tested revealed differences between the enzymes of the survivor strains except that in one of them the level of activity is 55–65% of the other. Quantitative immunological determinations of ADH gave estimates of enzyme protein which are proportional to the measured activity levels. These results are interpreted to indicate that different amounts of ADH protein are being accumulated in the two strains.
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  • 43
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    Journal of chemical ecology 13 (1987), S. 219-226 
    ISSN: 1573-1561
    Keywords: Ablation ; egg dispersion ; oviposition deterrent ; foretarsi ; palpi ; antennae ; Coleoptera ; Bruchidae ; Callosobruchus maculatus
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    Notes: Abstract Females ofCallosobruchus maculatus (F.) avoid ovipositing on host seeds already bearing conspecific eggs, and thus distribute eggs evenly among seeds. This behavior was presumed to be mediated by an ether-soluble “oviposition marker” that is deposited with the egg and can be extracted from egg-laden artificial hosts (glass beads). Ablation experiments revealed that the true factors promoting an even dispersion of eggs were perceived by the maxillary and labial palpi. In contrast, receptors on the antennae were largely responsible for avoidance of seeds treated with “oviposition marker.” Taken together, these results suggest that a careful distinction should be drawn between factors that promote spacing of eggs under natural conditions and general oviposition deterrents that may be isolated from both sexes.
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  • 44
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    Journal of chemical ecology 13 (1987), S. 2009-2022 
    ISSN: 1573-1561
    Keywords: Leptinotarsa decemlineata ; Coleoptera ; Chrysomelidae ; Colorado potato beetle ; deterrent receptor ; feeding deterrents ; alkaloids ; sugar receptor ; amino acid receptor ; chemoreception ; steroidal alkaloids ; antifeedants
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    Notes: Abstract The galeal chemosensory system of the adult Colorado potato beetle was used as a model to study the effects of alkaloids on insect gustation. Nine alkaloids, representing a wide range of structural types, were used. Their ability to stimulate chemosensory cells when presented in isolation and their ability to interfere with normal chemosensory processes were emphasized. None of the alkaloids stimulated chemosensory cells in a dose-dependent manner, although a few stimulated low-level activity from some cells. There was no evidence for a general “deterrent receptor” in these beetles. Some of the alkaloids had a marked inhibitory effect on normal chemosensory responses. Tomatine, solanine, papaverine, and sparteine significantly inhibited responses to amino acids (represented by GABA) while quinine and papaverine inhibited responses to sucrose. An attempt was made to correlate neurophysiological action of some alkaloids with their effects on feeding behavior. It was clear from this correlation that even a dramatic inhibition of sensory input by an alkaloid does not necessarily lead to measurable effects on behavior. The results are discussed in the context of current theories on the mode of action of alkaloids and other secondary plant compounds which may be involved in host recognition by phytophagous insects.
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  • 45
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    Journal of chemical ecology 13 (1987), S. 35-38 
    ISSN: 1573-1561
    Keywords: Coleoptera ; Silphidae ; Silpha novaboracensis ; steroids ; pregnanes
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Two novel steroids, 3α,7β-dihydroxy-14β-pregn-4-en-15,20-dione (1) and 3α,7β, 20ξ-trihydroxy-14β-pregn-4-en-15-one (4), have been characterized from the rectal gland ofSilpha novaboracensis (Coleoptera: Silphidae). Judging from the function of comparable pregnanes in another species ofSilpha, the compounds may play an antipredator role.
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  • 46
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    Journal of chemical ecology 13 (1987), S. 39-46 
    ISSN: 1573-1561
    Keywords: Solanum ; glycoalkaloid ; Leptinotarsa decemlineata ; protein ; growth ; Coleoptera ; Chrysomelidae ; α-tomatine ; α-solamarine ; β-solamarine ; α-solamine ; α-chacomine
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    Notes: Abstract Growth of larvae of the Colorado potato beetle,Leptinotarsa decemlineata (Say), as measured by weight gain, was determined when larvae were reared on synthetic diets containing measured quantities of protein and one of fiveSolanum glycoalkaloids. Data were analyzed to determine if growth was affected by these two aspects of phytochemical variation independently, or if there was a significant interaction component in larval weight gain to simultaneous variation in protein and glycoalkaloid concentration. For four of the five glycoalkaloids examined, a bivariate regression model without interaction accurately accounted for growth ofL. decemlineata larvae. For alpha-tomatine, however, a regression model with the addition of a (protein × glycoalkaloid) interaction term more accurately accounted for larval growth. The influence of this interaction was less than either protein or glycoalkaloid concentration alone. The variation in protein concentration accounted for most of the variation in larval growth, and high protein concentrations could more than offset the effect of high concentration of any of the five glycoalkaloids.
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  • 47
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    Journal of chemical ecology 13 (1987), S. 2069-2081 
    ISSN: 1573-1561
    Keywords: Drosophila ; D. mojavensis ; D. nigrospiracula ; D. mettleri ; Diptera ; Drosophilidae ; cactus ; alkaloids ; viability ; development ; longevity ; host-plant relationships
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    Notes: Abstract Drosophila mettleri is a soil-breeding, cactophilic drosophilid which lives in the Sonoran Desert. Several chemical constituents of cacti in this region have been identified as having major roles in insect-host plant relationships involvingDrosophila. For example, isoquinoline alkaloids, which are present in senita cactus, have been shown to be toxic to seven of the nine species tested. The two tolerant species areD. pachea, the normal resident, andD. mettleri. Necroses of senita cacti are often used as feeding substrates byD. mettleri adults, but this species has never been reared from senita rots. Soil, which have been soaked by juice from saguaro and cardón rots, are the typical breeding substrates of this species. The tissues of both of these cacti also contain alkaloids, chemically related to those in senita, but at much lower concentrations. Alkaloid concentration in saguaro-soaked soil was found to be 1.4–27 times the average concentration in fresh tissue. Alkaloids were extracted from saguaro tissue and used in tests of larva-to-adult viability, developmental rate, and adult longevity. Elevated concentrations of saguaro alkaloids had no significant effect on the longevity ofD. mettleri, but significantly reduced the longevity ofD. nigrospiracula andD. mojavensis, two nonsoil breeding cactophilic species. Viability and developmental rates of all three species were affected, but the effect onD. nigrospiracula was comparatively greater. It is argued that the adaptations that allowD. mettleri to utilize the saguaro soil niche also convey tolerance to alkaloids present in senita tissue. The ability to utilize senita necroses as feeding substrates represents an ecological advantage to D. mettleri, in that the density of potential feeding sites is increased as compared to species which are more specific in their host-plant relationships.
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  • 48
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    Journal of chemical ecology 13 (1987), S. 335-344 
    ISSN: 1573-1561
    Keywords: Kairomone ; parasite ; host finding ; host acceptance ; behavior ; Edovum puttleri ; Hymenoptera ; Eulophidae ; Colorado potato beetle ; Leptinotarsa decemlineata ; Coleoptera ; Chrysomelidae
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract When females of the eulophid parasiteEdovum puttleri were exposed to ann-hexane wash of eggs of the Colorado potato beetle,Leptinotarsa decemlineata, their responses indicated that the eggs contained a kairomone which elicited host-finding and host-acceptance behaviors. The hostfinding responses included an increased amount of time searching glass beads treated with kairomone, and drumming on the beads with the flagellum of the antennae. Host-acceptance responses included grasping of the beads with the legs, raising of the abdomen, and probing the kairomone-treated surface with the ovipositor. None of these responses were noted in females on beads treated only with hexane, or in males exposed to kairomone-treated beads. When kairomone was applied to a flat surface, filter paper disks, few episodes of drumming and no episodes of probing with the ovipositor were noted. Responses ofE.puttleri to eggs of Colorado potato beetle were similar to those on kairomone-treated beads, but females normally drilled into eggs and fed on host fluids after retracting the ovipositor. The kairomone is volatile, and responsiveness was reduced in parasites exposed to beads treated several hours previously.
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  • 49
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    Journal of chemical ecology 13 (1987), S. 2143-2157 
    ISSN: 1573-1561
    Keywords: Dendroctonus brevicomis ; Coleoptera ; Scolytidae ; pheromone ; synergism ; plumes ; exo-brevicomin ; frontalin ; myrcene
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    Notes: Abstract The relationships between catch ofD. brevicomis LeC. at sources of the synergistic pheromone components,exo-brevicomin (E) and frontalin (F), and increasing distance of separation of sources were investigated in the forest. The two components were each released with the host monoterpene, myrcene (M), in trap pairs. The traps of each pair were spaced apart at various distances (0–16 m) in either horizontal or vertical lines that were perpendicular to the mean wind direction. Both sexes were most strongly attracted when the two components were released from the same source, and increasing distance of separation between components caused exponential decreases in trap catch for all trap configurations. Males were significantly more attracted to traps with E, M alone than to corresponding traps with F, M alone, while females exhibited a preference for F, M. The theoretical relationships and properties of two coalescing plumes of individual components and their intersecting “active space” are presented and discussed. It is proposed that “confusion” or “communication disruption” techniques for insect control may be more successful if components are released individually from many points rather than released similarly in blends.
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  • 50
    ISSN: 1573-1561
    Keywords: 2-Methyl-3-buten-2-ol ; cis-verbenol ; trans-verbenol ; myrtenol ; trans-myrtanol ; 2-phenylethanol ; ipsdienol ; subtractive assay ; Ips typographus ; Coleoptera ; Scolytidae ; Picea abies ; host volatiles
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    Notes: Abstract Six compounds previously identified from hindguts of unmated maleIps typographus (L.) during host colonization: 2-methyl-3-buten-2-ol (MB),cis-verbenol (cV),trans-verbenol (tV), myrtenol (Mt),trans-myrtanol (tM), and 2-phenylethanol (PE), were tested for their attractivity in the field with a subtractive method. The amounts of MB and cV released from a pipe trap were similar to those given off from the commercial bait Ipslure as well as that from a Norway spruce tree,Picea abies (L.) Karst., under mass attack. The blend of the compounds became nonattractive when either MB or cV was subtracted, while subtraction of any of the other four compounds had no effect. Addition of ipsdienol (Id) to the blend did not significantly increase the attraction. In a second comparative test, the addition of three compounds as a group (tV + Mt + PE) to MB + cV again had no effect on the attraction, but the addition of Id increased the catch somewhat. Addition of host logs to a bait releasing MB + cV at a rate lower than in previous experiments did not influence the attraction to pipe traps. Sticky traps containing natural pheromone sources (50 males in a log), which released 1–5 mg/day of MB as determined by aerations with deuterated MB as internal standard, were less attractive than a synthetic source releasing similar amounts of MB.
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  • 51
    ISSN: 1573-1561
    Keywords: Diabrotica ; Coleoptera ; Chrysomelidae ; western com rootworm ; southern corn rootworm ; northern corn rootworm ; attractants ; semiochemicals ; veratrole ; estragole ; trans-anethole ; indole ; eugenol ; phenylacetaldehyde
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    Notes: Abstract During the summers of 1984 and 1985, a variety of structurally related benzenoid compounds was evaluated in sweet corn plots as attractants for adult southern corn rootworms (SCR), western com rootworms (WCR), and northern corn rootworms (NCR). Field response to the volatiles was measured by beetle counts on baited cylindrical sticky traps placed inside the corn plots at a height of l m above ground level. SCR adults were attracted late in the season (last week of August through September, 1984 and 1985) to numerous aromatic compounds, including phenylacetaldehyde, benzyl acetone, phenethyl alcohol, phenyl acetate, indole, veratrole, methyl eugenol, methyl isoeugenol, eugenol, and isoeugenol. Although many compounds attracted SCR adults late in the season, only veratrole, phenylacetaldehyde, and chavicol were significantly active in early and middle August 1985. WCR adults were attracted to a different group of compounds, namely estragole,trans-anethole, and indole. Estragole (4-methoxy-1-allylbenzene) was an effective WCR attractant from corn tasseling in early August 1985, until the end of the trapping period in late September and early October 1985. Indole andtrans-anethole (4-methoxy-1-propenylbenzene) were less effective attractants than estragole and were most active at the beginning and/or end of the corn season. Traps baited with 100 mg of estragole caught an average of 20 times more WCR adults than unbaited control traps, and the females outnumbered the males in the baited traps. Estragole dosage tests were conducted in three sweet corn plots on different dates in 1985 and the minimum effective dose ranged between 5 and 30 mg/trap. Field tests with structural analogs revealed the importance of the site of unsaturation in the allylic side chain of estragole and the effect of different ring substituents on WCR response. The phenylpropanoids, eugenol and isoeugenol, significantly attracted NCR adults, even though these beetles were in low abundance in the test corn plots. Field tests indicate there is no cross-species response by WCR and NCR adults to their related phenylpropanoid attractants. However, in late August, SCR adults do respond to some WCR and NCR attractants (indole and several eugenol analogs). Electroantennographic analysis of SCR males revealed they can perceive peripherally a wide range of benzenoid compounds.
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  • 52
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    Journal of chemical ecology 13 (1987), S. 1087-1097 
    ISSN: 1573-1561
    Keywords: Boll weevil ; Anthonomus grandis Boh. ; Coleoptera ; Curculionidae ; Rose-of-Sharon ; Hibiscus syriacus L. ; feeding deterrent ; unsaturated fatty acids
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The Rose-of-Sharon,Hibiscus syriacus (L.), can be a significant alternate host plant for the boll weevil,Anthonomus gradis (Boh.). Boll weevils are known to be deterred from feeding and ovipositing in the buds unless the calyx is removed. This investigation was initiated to identify calyx allelochemicals that deter feeding with the eventual strategy of breeding for cotton lines high in these allelochemicals in the appropriate tissues. The feeding deterrency of calyx tissue from the buds of Rose-of-Sharon for the boll weevil was confirmed. The most active deterrent fraction was found to contain mostly fatty acids and their methyl esters. Saturated fatty acids and their methyl esters were generally found to be stimulatory, while the unsaturated species were found to be deterrent. Higher quantities of the fatty acids, particularly the unsaturated species, were found in Rose-of-Sharon calyx tissue than in the buds without calyx. This supports the hypothesis developed through the isolational work and testing of standards that the unsaturated fatty acids are significant deterrents of boll weevil feeding.
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  • 53
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    Journal of chemical ecology 13 (1987), S. 1279-1292 
    ISSN: 1573-1561
    Keywords: Diabrotica sp ; kinetic resolution ; lipase ; methyl carbinol ; Mucor miehei ; pheromone ; western corn rootworm ; Coleoptera ; Chrysomelidae
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The relative rates of enzyme-catalyzed esterification of the enantiomers of 2-octanol with various acids were determined for several commercial lipases. Interesterifications and hydrolyses of racemic 2-octanol esters catalyzed by these enzymes were also examined. Novo'sMucor miehei lipase exhibited considerable enantioselectivity and was therefore employed to prepare 8-methyl-2-decanols with high configurational purity at the carbinol carbon. Esters of these alcohols had been previously identified as sexually attractive to several rootworm (Diabrotica) species, and the stereochemistry of those esters had been shown to be critical to the attraction. The enzymatic resolution provides a convenient method to obtain such esters in a desired state of configurational purity.
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  • 54
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    Journal of chemical ecology 4 (1978), S. 409-423 
    ISSN: 1573-1561
    Keywords: Coleoptera ; Dermestidae ; diel behavioral patterns ; 14-methyl-8-hexadecenal ; pheromone ; reproductive isolation ; Trogoderma glabrum ; T. inclusum ; T. variabile ; trogodermal
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    Notes: Abstract AdultTrogoderma glabrum, T. inclusum, andT. variabile exhibit diel periods of exposure-concealment behavior, the frequency and duration of which are age-dependent, and the temporal placement of which is species-dependent. Exposure periods correspond with daily maxima in male sensitivity to the most active female-released sex pheromone component, 14-methyl-8-hexadecenal, and with respective periods of sex pheromone release in females. Exposure-concealment behavior may be a factor in reproductive isolation between these species, since potential communication distances are greatly reduced when either males or females are concealed.
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  • 55
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    Journal of chemical ecology 4 (1978), S. 451-461 
    ISSN: 1573-1561
    Keywords: Coleoptera ; Dermestidae ; Attagenus megatoma ; canadensis ; japonicus ; schaefferi spurcus ; bicolor ; rufipennis ; elongatulus ; behavior ; sex pheromone ; calling ; bioassay ; black carpet beetle ; megatomoic acid
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    Notes: Abstract Females of severalAttagenus species demonstrated calling behaviors similar to those previously reported forA. elongatulus. Attagenus rufipennis females did not call until they were 12–14 days old. OtherAttagenus species called at approx. 4 days of age. All species exhibited diurnal periods of calling activity. Interspecific pheromone responses were tested, withA. megatoma megatoma, A. megatoma canadensis, A. megatoma japonicus, andA. schaefferi spurcus showing equal cross-responses. Male response to females was demonstrated inA. rufipennis andA. bicolor. Attagenus rufipennis, bicolor, andelongatulus males responded only to female extracts of their own species.
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  • 56
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    Behavior genetics 17 (1987), S. 541-558 
    ISSN: 1573-3297
    Keywords: mating ability ; sexual selection ; fitness ; stress ; domestication ; Drosophila
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    Topics: Biology , Psychology
    Notes: Abstract Mating ability differences between flies of different alcohol dehydrogenase (Adh) genotypes have been assessed in the temperature range 15 to 29°C for laboratory-adapted and field-derivedDrosophila melanogaster. Significant differences amongAdh genotypes were detected principally for the laboratory-adapted strains due to departures from random mating associated with heterozygote superiority at the relatively extreme temperature of 29°C, although mating ability differences could not be attributed directly to theAdh locus. The difference between the laboratory and the field populations can be explained by the effects of genetic back-ground manifested in the form of fitness differences, being enhanced for the laboratory-adapted flies as a consequence of the stress of laboratory culture. In contrast with larval survival and development time, laboratory and field flies do not differe appreciably in their overall abilities to obtain mates, which indicates that mating ability is a direct fitness character not greatly affected by laboratory culture. It follows that direct fitness traits are the least amenable to change under domestication.
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  • 57
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    Behavior genetics 17 (1987), S. 559-569 
    ISSN: 1573-3297
    Keywords: sexual selection ; Drosophila
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    Topics: Biology , Psychology
    Notes: Abstract Since Darwin's formulation of the theory of sexual selection a number of population biologists have developed models that explore the genetic consequences of his theory. In all these models it is assumed that two forces act to counterbalance the runaway process of sexual selection. That is, female preference for a certain male character tends to select for extreme forms of that character until natural selection exerts its forces to maintain the optimum male phenotype that is able to survive in its environment. In this paper, an alternative explanation for the origin of secondary sexual characters is proposed. It is suggested that polymorphism in secondary sexual characters may be maintained not as a direct result of selection for these characters but by being either linked to or as pleiotropic effects of some other feature of the mate recognition pattern. While there are no genetic data to support these observations inDrosophila at this time, there appears to be compelling evidence that mating success is not wholly dependent on the presence of these characters.
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  • 58
    ISSN: 1573-4927
    Keywords: Drosophila ; gene action ; esterase ; isozymes
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    Notes: Abstract It is shown that the gene controlling the synthesis of the organ-specific S-esterase of Drosophila virilis ejaculatory bulbs is located on the second chromosome (at approximate position 192.1±map units). The cells of the genital imaginal disks are determined for the synthesis of S-esterase 10–12 hr after the second molt. The organ-specific esterase can be detected after adult emergence only. It is preceded by an increase in RNA content and by enhancement of RNA synthesis in the cells of the ejaculatory bulbs. Interstock differences were found in the level of the activity of S-esterase, which is under the control of the X chromosome, as well as in the time of expression of enzyme activity, which is controlled by the fifth chromosome. It is suggested that the specific phenotypic expression of this enzyme depends on the system of genes with regulatory expression at both the transcriptional and posttranscriptional levels. The genetic control of the synthesis of the S-esterase described is a convenient model for studying mechanisms of gene activity regulation in eukaryotes.
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  • 59
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    Biochemical genetics 16 (1978), S. 757-767 
    ISSN: 1573-4927
    Keywords: substrate specificity ; alcohol dehydrogenase ; octanol dehydrogenase ; aldehyde oxidase ; Drosophila
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Starch and polyacrylamide gel electrophoresis were used to ascertain the substrate specificities of alcohol-oxidizing enzymes in 13 Drosophila species. The substrates used were a variety of long- and short-chain aliphatic alcohols, one aromatic alcohol, and benzaldehyde. Only one enzyme (product of a single-gene locus) showed significant NAD+-dependent alcohol dehydrogenase activity with short-chain aliphatic alcohols. The 13 species, belonging to four different Drosophila groups, all showed a similar complement of alcohol-oxidizing enzymes, although differences in electrophoretic mobility and in levels of activity existed from species to species. These findings are relevant to the adaptation of Drosophila to alcohol environments.
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  • 60
    ISSN: 1573-4927
    Keywords: Drosophila ; vermilion ; tryptophan oxygenase ; suppression ; epigenetic suppression
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    Notes: Abstract The suppressor gene,su(s)2, inDrosophila melanogaster restores the production of red and brown eye pigments for some purple and vermilion mutant alleles, respectively. We showed previously that the product of thesu(s)+ allele caused inhibition of the sepiapterin synthase A produced by the purple mutant but did not affect the wild-type enzyme. Suppression was accomplished by removingsu(s)+ from the genome. We now report that the tryptophan oxygenase, produced by suppressible vermilion alleles, is also inhibited by extracts fromsu(s)+ flies. The inhibition of the vermilion enzyme can be reduced or eliminated, respectively, by prior storage of the extract at 4 or −20°C or by boiling, whereas the wild-type enzyme is not affected by extracts ofsu(s)+ flies. Also, when the suppressible vermilion strain is raised on certain diets, brown eye pigment production occurs. This epigenetic suppression was reduced by the presence of an extra copy ofsu(s)+ in the genome. These data support a posttranslational mechanism for regulation of enzyme activity in which the activity of the mutant enzyme is reduced by the product of thesu(s)+ allele. How thesu(s)+ gene product can distinguish between the normal and the mutant forms of these two enzymes is discussed, along with other mechanisms for suppression that are currently under investigation.
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  • 61
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    Behavior genetics 17 (1987), S. 597-611 
    ISSN: 1573-3297
    Keywords: sexual selection ; sexual isolation ; Drosophila
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    Topics: Biology , Psychology
    Notes: Abstract The idea that sexual selection is responsible for most of the characters, morphological, physiological, and behavioral, that are observed as subserving the efficiency of the reproductive act as an important monitor of fitness is developed. As a corollary, sexual isolation is downgraded, being considered a relatively unimportant secondary process for which the term “mechanism” is singularly inappropriate. The reproductive isolation frequently observed between allopatric species appears to me to be mostly an incidental out come of the fine tuning of the intrapopulational efficiency of the process of sexual reproduction. Two points are stressed: first, sexual selection is a powerful means of serving fitness; and second, hybridization poses little threat to the integrity or future well-being of a species.
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  • 62
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    Molecular biology reports 12 (1987), S. 79-83 
    ISSN: 1573-4978
    Keywords: Drosophila ; 20-hydroxyecdysone ; puromycin ; protein synthesis ; cycloheximide ; imaginal wing disc
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The effect of cycloheximide and puromycin on 20-hydroxyecdysone-induced protein synthesis in wing discs of Drosophila melanogaster has been studied by one-dimensional and two-dimensional SDS polyacrylamide electrophoresis. It is found that puromycin, but not cycloheximide, when applied simultaneously with the hormone enhanced the hormone-induced synthesis of the ‘early’ and ‘late’ proteins. However, when puromycin was applied after hormone treatment, only the ‘late’ proteins were induced. The possible implication of these observations is discussed.
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  • 63
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    Bioscience reports 7 (1987), S. 239-246 
    ISSN: 1573-4935
    Keywords: antisense RNA ; hsp 23 ; Drosophila
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The specificity of action of antisense RNA for one ofDrosophila low molecular weight heat shock proteins (hsp 23) was tested at the translational level using the rabbit reticulocyte lysate cell-free system. T7 polymerase-driven transcripts of hsp 23 in the antisense orientation were mixed with mRNA from heat-shocked cells under various stringency conditions prior to translationin vitro. Although the four small hsps show considerable sequence homology in their coding sequences, antisense hsp 23 RNA was shown to specifically inhibit hsp 23 mRNA translation under both high (formamide, 45°C and low stringency (37°C conditions. This suggests that the 5′ leader and the ribosome binding region of mRNA are of prime importance in the specificity of action of antisense RNA at the translational level.
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  • 64
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    Cell & tissue research 189 (1978), S. 155-166 
    ISSN: 1432-0878
    Keywords: Levator ani muscle ; Rat ; Neuromuscular junction ; Castration ; Testosterone effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the neuromuscular junction (n.m.j.) of the androgen-sensitive levator ani muscle was studied in normal adult male rats, in 8-month-old rats castrated at the age of one month and in castrated rats treated with testosterone propionate (TP). Castration does not result in significant changes of the n.m.j. The density of synaptic vesicles and the postsynaptic junctional folds remain practically normal in spite of marked atrophy of the muscle. TP administration for 7 days results in marked changes in preand postsynaptic structures. There is slow progressive depletion of synaptic vesicles, appearance of cisternae and coated vesicles in axon terminals, and coalescence of coated vesicles with the plasma membrane. Coated vesicles are also found inside Schwann cells and among junctional folds. Dense core vesicles appear both in the axon terminals and in the postsynaptic area. Collateral sprouting of terminal axons with the formation of new immature junctions is observed. After 35 days of TP administration depletion of synaptic vesicles continues. Glycogen β-particles, mostly freely dispersed, occasionally seen in axon terminals 7 days after TP administration, subsequently increase in number. In the endplate zone of the muscle fibre increased protein synthesis is indicated by a rapid increase in ribosomes and irregularly located myofilaments and myofibrils. The appearance of n.m.j. after testosterone administration resembles that described after nerve stimulation; the degree of change is however less pronounced.
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  • 65
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    Cell & tissue research 189 (1978), S. 277-286 
    ISSN: 1432-0878
    Keywords: Maternal adrenalectomy ; Rat ; Influence on the adrenals of newborn animals ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Maternal adrenalectomy at 7 or 14 days of gestation produced increased cell necrosis within zona reticularis cells on the day of birth and at 24 or 48 h after birth. Small remnants or large portions of adrenocortical cells were present within macrophages. In otherwise normal adrenocortical cells, lipid droplets were incorporated within some mitochondria. Autophagocytosis of single mitochondria was observed within adrenocortical cells. Undoubtedly ultrastructural changes represent stimulation of adrenocortical cells in neonatal rats in response to maternal adrenalectomy.
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  • 66
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    Cell & tissue research 191 (1978), S. 501-506 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Ultrastructure ; Perivascular space ; Hormonerelease ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neural lobes from rats subjected to neurohypophysial hormone-releasing stimuli were examined electron microscopically following fixation in 4 % tannic acid in 2.5 % glutaraldehyde. This fixation allowed the delineation of the perivascular space in the neural lobe tissue. Measurement of the area of the perivascular space showed that it was significantly increased in the rats subjected to vagal stimulation and intraarterial calcium ions compared to the control rats. The rats which had been subjected to haemorrhage as a hormonereleasing stimulus did not show any significant change in the area of the perivascular space. The significance of these findings in relation to hormone release is discussed.
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  • 67
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    Cell & tissue research 191 (1978), S. 507-512 
    ISSN: 1432-0878
    Keywords: Odontoblasts ; Osteoblasts ; Cementoblasts ; Intercellular attachments ; Electron microscopy (SEM/TEM) ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Osteoblasts of the young rat cranium, and cementoblasts and odontoblasts of young rat molars were prepared by ethanol freeze-fracture prior to critical point drying for scanning electron microscopy (SEM) as well as conventional transmission electron microscopy (TEM) techniques. Critical point drying causes shrinkage which separates the lateral intercellular contacts between neighbours in the same sheet in the case of cementoblasts and osteoblasts, but not those between odontoblasts. These differences are considered to be of functional significance and need to be taken into consideration when formulating theories of calcium influx into the mineralizable matrix of the respective tissues.
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  • 68
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    Cell & tissue research 191 (1978), S. 513-523 
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Freeze-fracture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Nerve terminals in the palisade zone of the rat median eminence were investigated with freeze-fracture electron microscopy. Fracture face P of the specific terminals showed two populations of intramembranous particles (IMP): a large and a small variety. The large IMP-s often formed small irregular clusters. In nerve terminals the total number of both populations of IMP-s was considerably less than that found on P membrane faces of ependymal feet. On fracture face E of the nerve terminals, the number of IMP-s was about a quarter of that seen on fracture face P. On both fracture faces of most terminals a few small round impressions (or elevations respectively) were found which may be interpreted as broken necks of either exo- or endocytotic vesicles. Neither gap nor tight junctions occurred at lateral membranes of the specific axon terminals. Similarly, no membrane specializations were observed with freeze-fracturing on membrane areas adjacent to the basement membrane. The findings are discussed in relation to a possible exocytosis mechanism of the hypothalamic releasing and inhibiting hormones.
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  • 69
    ISSN: 1432-0878
    Keywords: Taste buds ; Circumvallate papillae ; Colchicine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary It is believed that differentiation and maintenance of taste buds in vertebrates is dependent on the trophic function of their sensory nerve supply. In the present work colchicine was injected into the circumvallate papilla of the rat. This produced a reversible blockade of neuroplasmic transport and disappearance of taste buds. Colchicine inhibited the further differentiation of bud cells, but apparently did not change the life cycle of the cells present already at the time of injection. It is speculated that the neurotrophic factors in this particular cell system are effective to induce cell differentiation only.
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  • 70
    ISSN: 1432-0878
    Keywords: Cholecalcin (vitamin D-dependent calcium-binding protein) ; mRNA ; Uterus ; In situ hybridisation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The molecular cloning of a cDNA fragment synthesised from rat duodenal mRNA coding for cholecalcin (calbindin), a 9000 Mr vitamin D-induced calcium-binding protein (CaBP), has been previously described. DNA/RNA hybridisation assays have been used to examine CaBP mRNA production in the uterine horns and duodena of pregnant (21 day) rats using the cloned CaBP cDNA. Northern hybridisation studies showed that the 32P cDNA sequence hybridised to a single 500–600 nucleotide species in both the uterus and the duodenum, thus demonstrating identical CaBP mRNA processing in both tissues. Dot blot hybridisation studies showed that the CaBP mRNA concentration was greatest in the duodenum while that of the uterine horns was about 10% of the duodenal level. The observed differences in CaBP mRNA levels correlate well with the in vivo CaBP concentrations. In situ hybridisation histochemistry using 3H cDNA revealed that CaBP mRNA visualised by silver grains was found in all the parts of the endometrium and the myometrium. However, CaBP mRNA was more concentrated in the outer and inner muscular fibres and in the luminal cells of the endometrium than in the stroma cells. These results demonstrate that the CaBP gene is expressed in specific cells of the rat uterus.
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  • 71
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Aminoglutethimide ; Corticosterone ; Morphometry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of a 7-day administration of aminoglutethimide (AG) on the adrenal zona fasciculata were examined in “normal” and dexamethasone/ACTH-treated rats. There was a 70–74% decrease in the concentration of corticosterone in blood, but no conspicuous qualitative changes suggesting cell degeneration occurred. Morphometry showed that AG induced a significant hypertrophy of the zona fasciculata and its parenchymal cells only in “normal” animals, which was due to an increase in the volume of the mitochondrial compartment and to proliferation of the smooth endoplasmic reticulum. This response to AG was considered to be non-specific and mediated by the enhanced secretion of ACTH following the decrease in the blood level of corticosterone. AG administration significantly increased the volume of the lipid-droplet compartment and the number of intramitochondrial lipid-like inclusions in both groups of animals. These changes were interpreted as the morphological counterpart of the AG-induced block of cholesterol utilization in steroid synthesis.
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  • 72
    ISSN: 1432-0878
    Keywords: Astrocytes ; Ependymal cells ; Circumventricular organs ; Tight junctions ; Orthogonal arrays of particles ; Freeze-fracturing ; Rat
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    Topics: Biology , Medicine
    Notes: Summary Ependymal cells in the ventricular wall and in several circumventricular organs of the rat were compared by means of freeze-fracturing. In principle, tight junctions and orthogonal arrays of particles (OAP) do not coexist in the cells bordering the ventricular wall: (1) Ordinary ependymal cells of the rat possess OAP and are devoid of tight junctions. (2) Epithelial cells of the rat choroid plexus are connected by tight junctions; OAP are lacking here. In some cases, however, tight junctions and OAP coexist in the same cell. In the boundary zone between choroid plexus and ependyma of the rat, the density of OAP is very low, whereas the tight junctions are well developed. In the subfornical and the subcommissural organ (SCO) of the rat both structures are poorly developed; in the SCO they occur segregated in different membranous areas. An overview of the literature confirms that tight junctions and OAP mostly exclude each other. The possibility that in astrocytes and ependymal cells tight junctions may have been replaced by OAP during phylogeny is briefly discussed.
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  • 73
    ISSN: 1432-0878
    Keywords: Teeth ; Dental pulp ; Periodontium ; Neurofilament protein ; Immunohistochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of nerve fibers in molars, periodontal ligament and gingiva of the rat shows a complex pattern. Decalcified material including the alveolar bone was sectioned in three different planes and stained by means of immunohistochemistry for detection of the neurofilament protein (NFP); the immunoreactive neural elements were clearly visualized in three-dimensional analyses. NFP-positive nerve fibers formed a subodontoblastic plexus in the roof area of the dental pulp; some of them entered the predentin and dentin directly through the dentinal tubules. This penetration was found mainly in the pulp horn, and was limited to a distance of about 100 μm from the pulpo-dentinal junction. In the periodontal ligament, NFP-positive nerve fibers were found densely distributed in the lower half of the alveolar socket. Two types of nerve terminals were recognized in the periodontal ligament: free nerve endings with tree-like ramifications, and expanded nerve terminals showing button- or glove-like shapes. The former tapered among the periodontal fibers, some even reaching the cementoblastic layer. The latter were located, frequently in groups, within the ligament restricted to the lower third of the alveolar socket. A well-developed plexus of NFP-positive nerves was revealed in the lamina propria of the free gingiva, the innervation being denser toward the epithelium of the gingival crevice. The characteristic distribution of NFP-immunoreactive nerve fibers revealed in this study is discussed in relation to region-specific sensations in the teeth and surrounding tissues.
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  • 74
    ISSN: 1432-0878
    Keywords: Epididymis ; Ductus deferens ; Myosin ; Actin ; Fibronectin ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The postnatal maturation of regions of the epididymis and intragonadal segment of the deferens duct was studied in the rat by light-and transmission electron microscopy. Maturation of the genital duct starts in the distal cauda epididymidis and ductus deferens after one week of life, and one week later, in the more cranial segments of the epididymis. Epithelial principal cells and peritubular contractile cells are structurally mature 35 days after birth. The synchronous changes of these cells indicate that the same factors control their postnatal maturation. The epithelial principal cells obtain an endocytotic apparatus and long stereocilia, whereas peritubular cells acquire contractile features. These changes are associated with a progressive increase in the immunoreaction for smooth muscle actin in both cell types. Smooth muscle myosin is detected in the apical region of the epithelial cells and the peritubular cell cytoplasm by day one of postnatal development. The differentiation of contractile cells in the wall is accompanied by progressive organization of the pericellular matrix into a continuous basement membrane. Although fibronectin is visible at birth, it is gradually removed from the tubule wall.
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  • 75
    ISSN: 1432-0878
    Keywords: Cardiac muscle cells ; Extracellular matrix ; Collagen fibers and filaments ; Immunohistochemistry ; Rat ; Hamster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphology, composition, and function of struts that interconnect the lateral surfaces of cardiomyocytes were examined in the hearts of rats and hamsters. Methods included brightfield and fluorescent light microscopy, secondary and backscatter scanning electron microscopy, and transmission electron microscopy in conjunction with silver stain, cationic dye, and antibody to type-I collagen. These studies reveal a twisted, beaded appearance and a complex substructure of collagen fibrils embedded in a ground substance that has a positive reaction with cationic dye. A hierarchy of patterns of branching and attachment was seen among intercellular struts ranging in diameter from 0.1 μm to several urn. The hypothesis that struts tether not only the surfaces but the contractile lattices of laterally adjacent myocytes is supported by the following: (a) the attachments of struts to the collagen weave of the sarcolemma, often lateral to the level of Z bands, (b) the presence of collagen type I in a composite material arrangement, (c) the relative dispositions and configurational changes of struts and myocyte surfaces in various physiological states and induced, non-physiological perturbations of cardiac muscle, (d) the corrugated sarcolemmas with infoldings near Z bands, and (e) the continuity of intracellular filaments from Z bands to the inner aspect of the sarcolemma in relaxed and contracted myocytes. Implications of struts acting as tethers and sites for storage of energy in the motions of myocytes during the cardiac cycle are discussed.
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  • 76
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    Keywords: GABA-treatment ; Superior cervical ganglion ; Synaptic plasticity ; Morphometry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The superior cervical ganglion (SCG) of adult rats was exposed to γ-aminobutyric acid (GABA) by means of long-term microapplication. Serial sections were cut from GABA-treated and control ganglia, and subsequently the fine structure of individual synapses was investigated. The quantitative analysis of structural parameters of studied synapses showed that significant changes consisting of (1) a reduction in size of presynaptic axon terminals, (2) a decrease in the number of synaptic vesicles, and (3) a diminution in the extent of the postsynaptic membrane thickening at the dendritic side developed as an effect of GABA-treatment. These results provide morphological evidence that long-term application of GABA to the SCG exerts a combination of effects on both presynaptic and postsynaptic elements. It is suggested that the structural changes observed in the fine structure of individual synapses within the SCG may play an integral role in the development of the synaptogenetic action of GABA.
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  • 77
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    Cell & tissue research 249 (1987), S. 325-329 
    ISSN: 1432-0878
    Keywords: Renin release ; Epithelioid cells ; Osmosensitivity of renin release ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Superfusion with hypoosmotic solutions stimulates renin release from rat epithelioid cells adherent to isolated glomeruli. This stimulatory effect may be related to the observed swelling of the secretory granules; the swelling may markedly increase the probability of pre-exocytotic fusions between the granule and cell membranes, and consequently increase the frequency of exocytotic events.
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  • 78
    ISSN: 1432-0878
    Keywords: Exocrine pancreas ; Secretion granules ; Effect of feeding ; Carbachol ; Stereology ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The size, number and volume per cell of secretion granules in rat exocrine pancreas have been measured using stereological techniques. The changes which occur as a result of feeding starved animals (90 min) or stimulating lobular fragments in vitro with carbachol are documented. In fasted animals mean acinar cell volume was estimated as 1670 μm3 and the cells contained an average of around 450 secretion granules with a corrected mean diameter of 0.70 μm. They occupied around 7% of cell volume. After feeding mean cell volume was about 1300 μm3 and the cells contained an average of about 190 granules per cell with a mean diameter of 0.58 μm. They occupied 3% of cell volume. A shift in the size frequency distribution of granule diameters occurred as a result of feeding. In vitro experiments in which lobules were induced to secrete with carbachol (10μM, 3 h, 37° C) had a similar effect. Mean cell volume was reduced from around 1760 μm3 to 1360 μm3, mean granule number from around 420 per cell to 180 per cell and the volume density of granules was reduced from about 8% to 3% of cell volume. There was no significant change in mean granule diameter or shift in the size-frequency distribution of granule diameters. Incubation of tissues with cycloheximide (1 mM, 3 h, 37° C) did not prevent secretion by carbachol but it prevented replacement of granules. As a consequence, depletion by carbachol was greater in the presence of cycloheximide, the granules being reduced to around 110 per cell and to only 2.5% of cell volume. We conclude that feeding causes a preferential loss of larger granules and that during secretion replacement of granules occurs. Some of these granules are smaller than those evident in the glands of starved animals.
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  • 79
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    Cell & tissue research 249 (1987), S. 443-449 
    ISSN: 1432-0878
    Keywords: Different strains ; Adrenal cortex ; Zonation ; Cellular composition ; Sex differences ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The zonation and cellular composition of the adrenal cortex of intact mature male and female rats of different strains (Chbb Thomm, CFY) and three strains of Wistar rats (W1, W2 and W3) at the age of 84–90 days were compared using morphometry. Both absolute and relative adrenal gland weights were higher in female than male rats. Rats of W3 and Chbb Thomm strains had the largest adrenals. These differences depended upon the higher volume of the zona fasciculata (ZF) and zona reticularis (ZR) in the W3 and Chbb Thomm strains than in the remaining animals. Females had larger adrenocortical zones than corresponding males. The average volume of the ZF cell ranged in males from 1589 μm3 (W1 strain) to 2111 μm3 (Chbb Thomm) and in females from 2249 μm3 (W1 strain) to 2894 μm3 (W3 strain). The average nuclear volume of the ZF cells was higher in female rats whereas there were no strain-and sex-differences in the size of zona glomerulosa (ZG) and ZR cells. The total number of parenchymal cells per pair of adrenals varied markedly among the studied strains, with the highest number in W3 and Chbb Thomm females. W3, Chbb Thomm and CFY females had larger number of parenchymal cells than males; the reverse was true for W1 strain whereas no differences were found among W2 male and female rats.
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  • 80
    ISSN: 1432-0878
    Keywords: Macula densa ; Intercellular spaces ; Ultrastructure ; Frusemide ; Tubulo-glomerular feedback ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In situ drip-fixation of superficial glomeruli and tubules in the rat kidney verified the results obtained from high pressure perfusion fixation studies indicating that distinct spaces normally exist between the cells of the macula densa. Following treatment with frusemide these intercellular spaces between the macula densa cells became closed in both drip-fixed and perfusion-fixed kidneys. These findings suggest that the variability of extracellular compartmentation found in the macula densa is unlikely to be an artifact but most likely represents changes in the in vivo status of the macula densa.
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  • 81
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Liver ; Nucleolus ; 4-amino-pyrazolo(3,4-d)pyrimidine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The nucleolar ultrastructural changes produced in adrenal zona fasciculata cells and hepatocytes of rats by 4-aminopyrazolo(3,4-d) pyrimidine (4-APP), an inhibitor of the lipoprotein synthesis, are described. Male rats were injected intraperitoneally for three consecutive days with 4-APP in sodium phosphate buffer (50 mg/Kg/day). On the 4th day, the animals were sacrificed and their adrenals and liver were processed for EM. The nucleoli of the adrenal zona fasciculata cells showed nucleolar fragmentation with loss of their normal reticular appearance, separation of fibrillar and granular components, extensive vacuolization and evidence of fibrillar centers. The hepatocyte nucleoli also exhibited fragmentation. These changes seem to be the morphological counterpart of alterations in rRNA synthesis and processing, since 4-APP inhibits “de novo” purine synthesis and thus interferes with its incorporation into RNA and DNA.
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  • 82
    ISSN: 1432-0878
    Keywords: Brain ; Immunohistochemistry ; Natural killer cells ; Monocytes ; Granulocytes ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This study reports a specific cross-reactivity of the three anti-human-hematopoetic-cell monoclonal antibodies, anti-Leu-7 (HNK-1), anti-Leu-11a (NKP-15), and anti-Leu-M1 (MMA), with different epitopes in the brain of the adult rat. The distribution of these epitopes in rat brain is determined by means of immunohistochemistry in paraffin-embedded frontal serial sections. The reaction pattern of anti-Leu-11a monoclonal antibody is very similar to that of polyclonal antibodies against the myelin basic protein. Both antisera give a specific reaction with myelinated fibers. Immunoreaction products with the anti-Leu-7 monoclonal antibody are found as diffuse, mostly punctiform material in the neuropil and even more evident as small granules coating the cell surface of many neurons. In the white matter anti-Leu-7 reveals a moderate reactivity, which occurs predominantly as spots and fine-stranded material within the myelinated fiber tracts. Anti-Leu-M1 immunoreactivity is present between myelinated fiber bundles of the white matter, where it has a reticulate appearance, and as fine-granulated material within the grey matter of the cortex and the nuclei. The characteristic feature in the grey matter is that of irregularly shaped immunopositive plaques, which are often located around small blood vessels. The cytoplasm of glial and neuronal cells appeared negative with this MAB. The exact topographical distribution of the Leu-7 and Leu-M1 epitopes throughout the rat brain is described. The present hypotheses concerning the nature of this shared antigenicity between hematopoetic cells and nervous tissue are discussed.
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  • 83
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    Cell & tissue research 250 (1987), S. 29-33 
    ISSN: 1432-0878
    Keywords: Pituitary gland, pars anterior ; Cysts ; Transplantation ; Differentiation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Hemipituitary glands from 30 rats were isotransplanted under renal capsules. At 1, 2, 4, 7 and 20 days after transplantation, the grafts were examined by light and electron microscopy. Two days after transplantation, the central area of graft showed necrosis; however, the peripheral area, where marginal cells of Rathke's cleft were ingesting the remnants of necrotic glandular cells, survived. Four days after transplantation, mitotic figures of marginal cells were observed. Seven days after transplantation, the damaged area of the graft disappeared, and Rathke's cleft was completely lined by marginal cells. Remnants of necrotic glandular cells were not seen in intercellular spaces or in the cytoplasm of marginal cells. Cystlike structures formed in the grafts; some were connected to Rathke's cleft by narrow cavities. The cavity-lining cells of the cysts were agranular and similar to those that lined Rathke's cleft. At 20 days after transplantation, granular cavity-lining cells appeared. It is suggested that marginal cells of immature rats can differentiate into granular cells.
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  • 84
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    Cell & tissue research 250 (1987), S. 21-27 
    ISSN: 1432-0878
    Keywords: Glomus cell ; Acetylcholinesterase ; Catecholamines ; Carotid body ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The localization of acetylcholinesterase (AChE) was investigated at the cellular and subcellular levels in dissociated cell cultures of the carotid body of the neonatal rat, prepared by the methods of Fishman and Schaffner (1984). In the presence of iso-OMPA, which blocks non-specific cholinesterase, staining was confined almost exclusively to glomus-cell clusters and occasional isolated cells. These clusters grow as discrete islands scattered throughout the culture and display typical catecholamine (CA) fluorescence as in vivo. AChE staining was abolished or reduced by the cholinesterase inhibitors eserine (30–100 μM), or (the poorly lipid soluble) echothiophate (8 (μM). Processing of the same culture sequentially for the demonstration of both AChE and CA revealed that glomus-cell clusters and individual glomus cells were consistently positive for both. In electron micrographs AChE reaction product was associated intracellularly with the nuclear envelope and cytoplasm of glomus cells (identified by their characteristic dense cored granules), as well as extracellularly with the boundaries of contiguous glomus cells. Significantly, reaction product occurred in some glomus cell profiles that had both dense-cored and clear (cholinergic-like) vesicles. These findings are discussed in the context of a possible dual (adrenergic/cholinergic) function status of glomus cells in the rat's carotid body.
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  • 85
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    Cell & tissue research 250 (1987), S. 181-184 
    ISSN: 1432-0878
    Keywords: Prolactin cell ; Secretory granule ; Glycoconjugate ; Lectin ; Concanavalin A ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Prolactin granules in the anterior pituitary glands of male rats contain densely stained materials at the periphery of the matrix. These occur in both small spherical and large polymorphic types of granules. The presence of densely stained materials around secretory granules may be a useful criterion for identification of prolactin cells since the dense structure was observed in 95% of these cells after conventional staining by uranyl acetate and lead citrate. The localization of glycoconjugates in the prolactin granules was examined by applying concanavalin A (Con A) on the ultrathin sections. HRP-Con A or ferritinconjugated Con A bound specifically to the densely stained materials in the peripheral region of the prolactin granule matrix, indicating that this densely stained matrix contains glycoconjugates; the significance thereof is discussed with reference to the concentration and packaging of secretory product.
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  • 86
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    Cell & tissue research 188 (1978), S. 345-359 
    ISSN: 1432-0878
    Keywords: Hippocampal subfields ; Rat ; Volumes ; Timm stain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The absolute volumes of the hippocampal and subicular cortical layers in the rat were determined. The boundaries of the various layers were defined on series of sections made through the entire hippocampal region of five rats and stained according to the Timm sulfide silver technique. Coordinates representing the boundaries of the layers on selected sections were fed into a mini-computer programmed to calculate the volume of the layers from the areas of the profiles and the distances between the sections. The distribution of the layers indicates that they constitute the same proportion of the volume of the dorsal and ventral divisions of the hippocampal region, with the exception of the structures lying in regio inferior and regio superior. Although the combined regio superior and regio inferior components of the layers of Ammon's horn occupy the same percentage of the volume of the dorsal and ventral hippocampal regions, the regio superior components occupy a larger percentage of Ammon's horn in the dorsal region than they do in the ventral region. The inter-animal variations in the volumes of the various layers indicate that it is possible to describe quantitatively the subdivisions of the hippocampal region with a precision that is compatible with comparative studies.
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  • 87
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    Cell & tissue research 188 (1978), S. 491-496 
    ISSN: 1432-0878
    Keywords: Castration ; LH-cells ; Rat ; Development ; Sex-steroids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The effects of sex-steroids on the LH-cell development in neonatal rats were studied. The cells were stained immunohistochemically by applying anti-HCG serum. On the second day after birth some of the animals of both sexes were gonadectomized and simultaneously injected with testosterone or estradiol (50 or 200 μg). The remaining animals were either gonadectomized or injected with either one of the sex-steroids. The LH-cell numbers in each group were determined on the 12th day of age from serially cut histological sections of the pituitary. In castrated males the number of LH-cells was about twice that of the intact animals. In the so-called sex-zone, LH-cells tended to be hypertrophied in castrates. These alterations in the appearance of LH-cells did not occur after ovariectomy. In gonadectomized animals injected with sexsteroids (200 μg), the cells were markedly reduced in number and size, both in males and females. Testosterone injection (50 μg) into intact newborn animals also suppressed the numerical development of LH-cells, especially in females. These alterations were particularly evident in the sex-zone in both sexes. Thus the present findings show that sex-steroids may be involved in sexual differences in morphological development of LH-cells in newborn rats.
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  • 88
    ISSN: 1432-0878
    Keywords: Adrenal gland ; Rat ; Vinblastine ; Corticosterone ; Exocytosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Vinblastine treatment blocks corticosterone release from rat adrenal zona fasciculata without impairing hormone synthesis, and induces the formation of acid phosphatase-positive granular clumps at the juxta-sinusoidal pole of the cells. Autoradiography shows that ACTH administration to vinblastine-treated animals mobilizes the 3H-cholesterol stored in the lipid droplets and leads to a noticeable labelling of the granular clumps. The possible significance of these granules is discussed.
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  • 89
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    Cell & tissue research 247 (1987), S. 441-444 
    ISSN: 1432-0878
    Keywords: Growth hormone-releasing factor (GRF) ; Neuropeptide immunocytochemistry ; Trigeminal ganglion ; Spinal ganglion ; Development, ontogenetic ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Growth hormone-releasing factor (GRF)-like immunoreactivity has been demonstrated in the trigeminal and spinal ganglia of fetal, young and adult rats by use of peroxidase-antiperoxidase immunohistochemistry. GRF-like-immunoreactive cells first appear during the second half of embryonic life, as early as day 17. In untreated animals the GRF-immunoreactive elements form approximately 1% of all ganglion cells in the trigeminal and spinal ganglia; their numbers do not change significantly during development. The granular immunoreaction product is confined to perikarya, especially to the perinuclear region. Nerve fibers displaying GRF-like immunoreactivity were found neither in the ganglia, nor in the corresponding central and peripheral areas of termination. The possible role of GRF in sensory ganglia is discussed.
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  • 90
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    Cell & tissue research 247 (1987), S. 565-572 
    ISSN: 1432-0878
    Keywords: Synapses ; Perforated synapses ; Synaptic plasticity ; Serial section reconstructions ; Synaptic curvature ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphology of perforated synapses in the molecular layer of rat parietal cortex has been studied in 28-day-old animals. Of the perforated synapses analyzed, 92% were axospinous and of these all had asymmetrical contacts. A spinule was present in 20% of them, and 63% had a negative curvature (concave with respect to the presynaptic terminal) overall. Up to 95% of perforated synapses had one or more negatively-curved segments. The perforated synapses studied were characterized by postsynaptic densities (PSD) with a mean length of 581 nm, compared with 233 nm for non-perforated synapses. A study of over 100 serially sectioned synapses demonstrated that, in perforated synapses, the PSD and perforations often had a highly irregular shape and arrangement, the site of the perforation frequently projected into the presynaptic terminal, and coated evaginations of membrane, or coated vesicles, were sometimes found at the site of a perforation or towards the periphery of perforated PSDs. Preliminary reconstructions of perforated synapses suggest that, for descriptive purposes, three types can be recognized. Criteria are formulated for determining, on the basis of a study of single sections, which non-perforated profiles belong to perforated synapses.
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  • 91
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    Cell & tissue research 248 (1987), S. 49-54 
    ISSN: 1432-0878
    Keywords: Enterochromaffin cells ; Serotonin ; Duodenum ; Immunocytochemistry ; Electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Enterochromaffin cells of the rat duodenum have been studied immunocytochemically by use of a specific antiserum to serotonin. At the light-microscopic level serotonin immunoreactivity was observed in enterochromaffin cells located in the epithelium of the duodenal mucosa. Most of the serotonin-immunoreactive material was localized to the basal portion of the enterochromaffin cells, but small amounts of immunoreactive material were regularly observed in the apical portion. At the electron-microscopic level serotonin immunoreactivity in enterochromaffin cells was found to be concentrated over the dense cores of the cytoplasmic granules. The majority of these granules was located in the basal cytoplasm of the enterochromaffin cells, but serotonin-immunoreactive granules were also observed in the apical cytoplasm immediately beneath the microvilli. These observations indicate that duodenal enterochromaffin cells are bipolar and that they secrete serotonin both basally, to the circulation, and apically, to the gut lumen. Rat duodenal enterochromaffin cells thus appear to have an exocrine as well as an endocrine function.
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  • 92
    ISSN: 1432-0878
    Keywords: TRH ; Insulin ; Pancreas ; Streptozotocin ; Regeneration ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Streptozotocin treatment at birth induces, in the pancreas of rats, first depletion of insulin and thyrotropin-releasing hormone and then early regeneration ofβ cells and insulin, but not TRH. This study was undertaken to investigate whether the reduction in pancreatic TRH content can be associated with changes in the intensity and the distribution of TRH-immunoreactivity, and to follow the pattern of regeneration ofβ cells through insulin- and TRH-immunoreactivity. In control animals, strong TRH-immunoreactivity was seen in insulin-containing cells on days 1–4 after birth. At day 7, the TRH-immunoreactivity was already decreased. In contrast, insulin-immunoreactivity was present throughout the neonatal period. A sparse population of cells near ducts also contained both TRH- and insulin-immunoreactivity at 1–2 days age. In streptozotocin-treated animals, TRH-immunoreactivity is found only in a few scattered insulin-containing cells in altered islets on days 1–4. Near the ducts, there were new insulin-containing cells which did not contain TRH. From day 7 regeneration of endocrine cells was characterized by new, typical islets, but these contained insulin-, but not TRH-immunoreactivity. These findings suggest a differential control of the biosynthesis of insulin and TRH within the pancreas.
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  • 93
    ISSN: 1432-0878
    Keywords: Neuromuscular synapse ; Lectin histochemistry ; Dolichusbiflorus agglutinin ; Synaptogenesis ; Denervation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The binding of agglutinin fromDolichus biflorus (DBA) and other lectins (Concanavalin A, agglutinin from wheat germ and lectin fromBandeiraea simplicifolid) to synaptic and extrasynaptic portions of the basal lamina of muscle fibers, was studied with histochemical methods. In rat muscle, DBA-binding is specifically detected at the basal lamina of neuromuscular junction. However, long-term (6 months) denervated end-plate in adult rat muscle failed to bind DBA. During normal development, synaptic DBA receptors appear later than acetylcholine receptors or acetylcholinesterase at the rat neuromuscular junction. Generalized DBA-binding to motor end-plates is first visualized in 3-day-old rats, but section of sciatic nerve in 1-day-old rats prevents the appearence of synaptic DBA-binding on the leg end-plates. It is suggested, therefore, that the synaptic DBA receptors could be related to the postnatal stabilization of rat neuromuscular synapses.
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  • 94
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    Cell & tissue research 248 (1987), S. 699-702 
    ISSN: 1432-0878
    Keywords: Albumin ; Ovarian follicles ; Granulosa cells ; Immunocytochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The purpose of this study was to investigate whether albumin (Alb) can be detected in ovarian rat granulosa cells. Using immunocytochemistry and morphometrics, the percentages of Alb-positive follicles (follicle-index), of Alb-positive granulosa cells (granulosa-index), and of strongly reacting follicles (intensity-index) were evaluated in intact and regressing follicles of different diameter groups during different stages of the estrous cycle. In intact follicles, the follicle- and the granulosa-index increased from small-sized to large-sized follicles. Although the follicle-index did not change in any group during the stages of the estrous cycle, the granulosa-index was higher during proestrus than during the other stages. Intact follicles showed a stronger immunoreactivity than regressing follicles throughout the stages of the estrous cycle. Thus, Alb may be a requirement for the control of follicle growth in fertile rats. This Alb function may be attributable to Alb binding to specific cell-membrane components followed by the intracellular uptake of Alb-bound substances.
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  • 95
    ISSN: 1432-0878
    Keywords: Androgen ; Estrogen ; Pituitary ; Autoradiography ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Castrated male and female rats pretreated with dihydrotestosterone (DHT) were injected i.v. with 3H-estradiol (E2). Nuclear uptake and retention of 3H-E2 was measured in each of five cell types of the anterior pituitary gland using a combined quantitative autoradiographic and immunocytochemical procedure. In non-pretreated groups, each cell type bound a characteristic amount of ligand but no sex differences were apparent. DHT pretreatment, however, caused a significant decrease in 3H-E2 retention by gonadotrophs in both males and females. The treatment also caused a decrease in binding by lactotrophs and somatotrophs, but only in the females. No other cell types were altered. Thus, androgen appears to modulate E2 binding and retention by pituitary cells in both a cell-type and sexdependent manner. Our results also indicate that the inhibitory effects of androgens on E2 binding by the pituitary gland is more complex than can be explained by simple competition for the estrogen receptor.
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  • 96
    ISSN: 1432-0878
    Keywords: Lectin histochemistry ; Transport epithelia Immunolocalization: (Na++K+)-ATPase, carbonic anhydrase ; Kidney collecting ducts ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary To identify precisely the structural and functional cell type in the collecting duct of the rat kidney expressing binding sites for Dolichos biflorus agglutinin (DBA), we stained serial paraffin sections of kidney with horseradish peroxidase-labeled DBA and with immunocytochemical methods for localizing (Na++K+)-ATPase and carbonic anhydrase II (CA II), enzymes found preferentially in principal and intercalated cells, respectively. Most principal cells expressing a strong basolateral staining for (Na+ + K+)-ATPase showed binding sites for DBA at their luminal surfaces. However, a minority of cells rich in CA II and showing morphologic characteristics of intercalated cells also expressed DBA binding sites at their luminal surface and apical cytoplasm. These data suggest that DBA cytochemistrycan provide a useful tool for studying the functional polarity of the main cell types of the collecting duct of the rat kidney.
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  • 97
    ISSN: 1432-0878
    Keywords: Immuno-electron microscopy ; Triple-immunogold-labeling ; CRF axon terminal ; Median eminence ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural appearances of axonal terminals containing corticoliberin (CRF) were examined in the rat median eminence prepared by a freeze-drying procedure. Immunolabeling was performed by using 5-, 8-, or 15-nm gold-antibody complexes for CRF, arginine vasopressin (VP) and methionine-enkephalin-octapeptide (Enk-8), singly or in combination. In intact animals, the CRF-containing secretory granules were only slightly labeled with goldanti-VP or -Enk-8. In adrenalectomized rats, granules within single axons appeared to be labeled with all the immunogold complexes. This intragranular colocalization of the three antigens was confirmed by using three neighboring sections of the same axon terminals which were stained separately with each one of the antibodies and visualized with the avidin-biotin-peroxidase complex method. The granules labeled for CRF had decreased 9 days after adrenalectomy but had increased again by day 21, while those labeled for VP steadily increased after adrenalectomy. However, this did not correspond with the appearances of cell bodies in the paraventricular nucleus; the cell bodies labeled for both CRF and VP steadily increased in number and in stainability. By contrast, Enk-8 immunoreactivity in the axonal terminals and cell bodies was not affected by adrenalectomy. These findings suggest that although the three peptides could be released simultaneously from the axonal terminals, VP may play some special role in the expression of CRF activity.
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  • 98
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    Cell & tissue research 249 (1987), S. 577-586 
    ISSN: 1432-0878
    Keywords: Parotid gland ; Duct cells ; Ferritin ; Endocytosis ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ability of the intralobular ducts of the rat parotid gland to take up protein from the lumen was examined after retrograde infusion of native and cationized ferritin. At high concentrations (3–10 mg/ml), cells of both intercalated- and striated ducts avidly internalized the tracers. No differences were noted in the mode of uptake or fate of native or cationized ferritin. Large, apical ferritin-containing vacuoles up to 5 μm in size were present in cells of the intercalated ducts after infusion for 15 min. Small, smooth-surfaced spherical or flattened vesicles and tubules containing ferritin were also observed, often in association with the large vacuoles. Ferritin uptake increased with increasing infusion time, up to 1 h. Uptake by the striated ducts was less consistent than by the intercalated ducts, and occurred mainly in small vesicles and tubules. Secondary lysosomes became labeled with ferritin in both cell types. Ferritin was not observed in the Golgi saccules, nor was it discharged from the cells at the basolateral surfaces. At low concentrations (0.3–1 mg/ml), uptake was reduced, especially by cells of intercalated ducts, and differences were noted in the behavior of the two tracers. Cationized ferritin was internalized mainly into vesicles and tubules of cells of striated ducts; little uptake of native ferritin occurred at low concentrations. These results demonstrate that the ductal cells of the salivary glands are capable of luminal endocytosis of foreign proteins. They also suggest that in addition to modifying the primary saliva by electrolyte reabsorption and secretion, and secretion of various glycoproteins, the ductal cells are able to reabsorb proteins secreted by the acinar cells.
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  • 99
    ISSN: 1432-0878
    Keywords: γ-Aminobutyric acid (GABA) ; Autoradiography ; Development, ontogenetic ; Duodenum ; Uptake sites ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The localization of high-affinity uptake sites for 3Hγ-aminobutyric acid (3H-GABA) was investigated in the rat duodenum during ontogenesis and also at the adult stage (from 15.5 days of fetal life up to 105 days post natum) by means of low- and high-resolution autoradiography. At all stages studied, specific endocrine cell types of the epithelium were labelled and an intense uptake was detected in the nervous tissue, especially in glial cells but also in scarce neurones. When the incubation medium was supplemented with β-alanine (1 mM), a blocker of the glial uptake for GABA, the labelling persisted only in endocrine cells and in few neurones. The intensity and the frequency of the labelling decreased at later periods compared to the earlier developmental stages. The GABA content of the duodenum as measured by a new ion-exchange column chromatography-HPLC-coupled method was higher in the early postnatal period compared to later stages. These observations suggest that GABA, in addition to being a neurotransmitter, may play an important role during development of the duodenum.
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  • 100
    ISSN: 1432-0878
    Keywords: 7B2 polypeptide ; Gastro-intestinal tract ; Endocrine cells ; Immunohistochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Immunoreactivity to the polypeptide designated “7B2” recently isolated from human and porcine pituitary glands, appears to be consistently confined to neuroendocrine and endocrine cells in various tissues. In rat gut, immunoreactive 7B2 was found in endocrine-paracrine cells. Highly labeled cells were found in the antrum of the stomach and, cells with lower concentrations, in the fundus, duodenum, jejunum and ileum. Except for a few cells which were simultaneously positive for 5-hydroxytryptamine, and a few others showing Grimelius's reaction, “7B2” cells do not exhibit argentaffin and/or argyrophil character. The 7B2 polypeptide seems to be distributed amongst several different types of endocrine cells in the gut.
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