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  • Immunohistochemistry  (147)
  • growth
  • stability
  • Springer  (331)
  • Annapolis, MD
  • Firenze University Press
  • Kiel: Kiel Institute for the World Economy (IfW)
  • MDPI Publishing
  • Open Book Publishers
  • 1985-1989  (331)
Collection
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Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Entomologia experimentalis et applicata 53 (1989), S. 257-265 
    ISSN: 1570-7458
    Keywords: Antifeedant ; insecticide ; bisabolangelone ; analog ; feeding ; growth ; molting ; mortality ; sesquiterpenoid ; development ; phago-stimulant ; Pieris brassicae L. ; Lepidoptera ; Pieridae ; Angelica silvestris L. ; Umbelliferae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Bisabolangelone und drei Analoge wurden unter Laboratoriumsbedingungen auf ihre frasshemmende Wirkung in Raupen von Pieris brassicae L. (Lepidoptera: Pieridae) geprüft. Die Resultate von Zweifach-Wahlversuchen zeigten, dass sowohl die frasshemmende als auch die insektizide Wirkung von Bisabolangelone in den Analogen stark reduziert ist oder ganz verloren ging. Weitere Untersuchungen mit niedrigen Bisabolangelone-Dosen zeigten, dass das Fehlen von wohlschmeckender Nahrung zu einer drastischen Reduktion der Nahrungsaufnahme und des Wachstums der Raupen sowie zur Verhinderung der Häutung und zu hoher Mortalität führt. Deformationen, wie sie von bisabolangelone-behandelten Vorratsschädlingen gemeldet wurden, konnten bei P. brassicae nicht beobachtet werden.
    Notes: Abstract Bisabolangelone and three analogs were assayed, under laboratory conditions, for their antifeedant activity against Pieris brassicae L. (Lepidoptera: Pieridae) larvae. The results of dual-choice studies revealed that the potent antifeedant activity of bisabolangelone is greatly reduced or lost in the analogs. Insecticidal activity observed in the former was not detected either. Further studies using the lower rates of bisabolangelone showed that the absence of a preferable food resulted in a drastic reduction in feeding and growth, and produced high mortality and inhibition of molting. No developmental deformities reported in stored product insects treated with bisabolangelone were observed in P. brassicae during our studies.
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  • 2
    Electronic Resource
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    Journal of dynamics and differential equations 1 (1989), S. 269-298 
    ISSN: 1572-9222
    Keywords: Geometric mechanics ; reduction ; stability ; chaos ; rigid body dynamics ; periodic orbits ; 58F
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We give a complete bifurcation and stability analysis for the relative equilibria of the dynamics of three coupled planar rigid bodies. We also use the equivariant Weinstein-Moser theorem to show the existence of two periodic orbits distinguished by symmetry type near the stable equilibrium. Finally we prove that the dynamics is chaotic in the sense of Poincaré-Birkhoff-Smale horseshoes using the version of Melnikov's method suitable for systems with symmetry due to Holmes and Marsden.
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  • 3
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    Journal of dynamics and differential equations 1 (1989), S. 299-325 
    ISSN: 1572-9222
    Keywords: Commodity markets ; time delays ; stability ; Hopf bifurcation ; 34K15 ; 45J05 ; 90A16
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract A model for the dynamics of price adjustment in a single commodity market is developed. Nonlinearities in both supply and demand functions are considered explicitly, as are delays due to production lags and storage policies, to yield a nonlinear integrodifferential equation. Conditions for the local stability of the equilibrium price are derived in terms of the elasticities of supply and demand, the supply and demand relaxation times, and the equilibrium production-storage delay. The destabilizing effect of consumer memory on the equilibrium price is analyzed, and the ensuing Hopf bifurcations are described.
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  • 4
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    Celestial mechanics and dynamical astronomy 47 (1989), S. 333-359 
    ISSN: 1572-9478
    Keywords: symplectic maps ; stability ; normal forms
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We prove that non resonant isochronous symplectic maps in a neighborhood of an elliptic fixed point are stable for exponentially long times with the inverse of the distance from the fixed point. In the proof we make use of the majorant series method together with an idea for optimizing remainder estimates first applied to Hamiltonian problems by Nekhoroshev.
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  • 5
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    Journal of statistical physics 54 (1989), S. 1427-1427 
    ISSN: 1572-9613
    Keywords: Kink propagation ; kink width ; characteristic functions ; stability ; continuum of modes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We consider the propagation of kinks in an elastic chain in a bistable or multistable potential under the action of a driving force [M. Büttiker and H. Thomas,Phys. Rev. A 37:235 (1988)]. Each element of the chain is subject to a damping force proportional to its velocity. We show that both the propagation velocity of the kinks as a function of the driving field, and the kink width as a function of propagation velocity, are determined by characteristic functions which depend only on the form of the potential. These functions can be found by considering a single particle moving in the upside-down potential of the chain. The general properties of these functions are studied and illustrated by several examples. The stability of these driven kinks is discussed. Interestingly, we find in addition to the expected discrete localized eigenmodes a two-dimensional continuum of oscillatory modes with a localized envelope.
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  • 6
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    Journal of statistical physics 55 (1989), S. 141-156 
    ISSN: 1572-9613
    Keywords: Kosterlitz-Thouless ; Coulomb gas ; hierarchical model ; renormalization group ; screening ; stability ; bifurcation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A hierarchical version of two-dimensional lattice Coulomb gases is investigated. Forβ〉β c=8π there is a locally stable line of fixed points for the renormalization group (“block charges”) transformations. For $$\beta 〉 \bar \beta _c (\beta _c \leqslant \bar \beta _c \leqslant \tfrac{3}{2}\pi \beta _c )$$ , these fixed points are globally stable. As a consequence we show that there is no screening of external charges for any activity if $$\beta 〉 \bar \beta _c $$ . Atβ c a supercritical bifurcation takes place and we investigate the behavior of the model forβ≲β c to show a weak form of screening.
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  • 7
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    Landscape ecology 3 (1989), S. 43-51 
    ISSN: 1572-9761
    Keywords: Czechoslovakia ; CSSR ; Slovakia ; ecological model ; planning ; landscape management ; stability ; disturbance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Development of the general ecological model (EM) of the CSSR has been included in the state program for environmental policy - the Ecoprogramme of the CSSR — at a scale of 1:1 000 000 for the entire Czechoslovak territory and at a scale of 1:500 000 for the Czech Socialist Republic (CSR) and the Slovak Socialist Republic (SSR). The objective of the first EM stage was to make a survey of spatial differentiation of the major ecological problems of the country. The EM consists of four parts, three analytical and one synthetic. These parts are: a. The ecological state (value) of the current spatial structure of the landscape. b. Ecological stress factors in the landscape. c. Protection of nature and natural resources. From the spatial synthesis of these three groups (from their spatial encounters), the following synthetic group of conditions was obtained: d. Regional ecological problems, a system of ecologically stable areas, environmental stress factors and factors endangering the ecological stability of the landscape, the natural resources and the human environment.
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  • 8
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    Acta mechanica solida Sinica 2 (1989), S. 285-294 
    ISSN: 0894-9166
    Keywords: Liapunov function ; stability ; discrete time system ; decision matrix
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The purpose of this paper is to present a new method for constructing Liapunov function and determining the stability of discrete time systems with a computer on the basis of the similarity transformation theory by directly applying the system matrix of the system under discussion instead of solving the discrete Liapunov's matrix equation.
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  • 9
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    Pure and applied geophysics 130 (1989), S. 743-749 
    ISSN: 1420-9136
    Keywords: Dynamic systems ; multiple equilibrium ; stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract A set of ordinary differential equations describing a mechanical system subject to forcing and dissipation is considered. A topological argument is employed to show that if all time-dependent solutions of the governing equations are bounded, the equations admitN steady solutions, whereN is a positive odd integer and where at least (N−1)/2 of the steady solutions are unstable. The results are discussed in the context of atmospheric flows, and it is shown that truncated forms of the quasigeostrophic equations of dynamic meteorology and of Budyko-Sellers climate models satisfy the hypotheses of the theorem.
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  • 10
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    Aquatic sciences 51 (1989), S. 296-305 
    ISSN: 1420-9055
    Keywords: Arctic char ; growth ; maturation ; reoligotrophication ; Lake Walenstadt
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Within one decade the yield in arctic char fishery of Lake Walenstadt (Switzerland) has dropped from 1.7 kg · ha−1 to 0.7 kg · ha−1. In the same period growth decreased by about 15%. The fish considered as “degenerated dwarfed chars” by fishermen are supposed to mature in very young ages. The change of the growth pattern can be related to reoligotrophication of the lake and impoverishments of the food source. Compared to other arctic char populations in Switzerland maturation takes place at least one year later.
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  • 11
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    Cell & tissue research 258 (1989), S. 53-63 
    ISSN: 1432-0878
    Keywords: GABA ; Immunohistochemistry ; Salivary neurones ; Schistocerca gregaria (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neurones in the suboesophageal ganglion of the locust Schistocerca gregaria were stained with an antiserum raised against gamma amino butyric acid (GABA). This ganglion consists of the fused mandibular, maxillary and labial neuromeres. Immunoreactive cell bodies of similar size and distribution occur in the lateral, ventral and middorsal regions of all three neuromeres. Approximately 200 cell bodies stain in both the mandibular and maxillary neuromeres and 270 in the labial neuromere. A few distinctly larger cells occur in the ventral groups and one large pair occurs in the lateral group of the maxillary neuromere. Dorsal commissures DCIV and DCV are composed mainly of stained fibres, while DCI–DCIII are largely unstained. A ventral commissure also stains in the maxillary neuromere. All longitudinal tracts contain both stained and unstained fibres. Many processes within the neuropil are also immunoreactive. A stained axon is found in the posterior tritocerebral commissure which enters the anterior dorsal region of the mandibular neuromere. The salivary branch of the 7th nerve contains one stained axon and two axons stain in nerve 8 which innervates neck muscles.
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  • 12
    ISSN: 1432-0878
    Keywords: Gastrointestinal tract ; Gastric mucosa ; Gastrointestinal endocrine cells ; Immunohistochemistry ; Suncus murinus (Insectivora)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of endocrine cells in the gastrointestinal tract of the house musk shrew, Suncus murinus (Family Soricidae, Order Insectivora) was studied immunohistochemically. The hormones investigated were gastrin, cholecystokinin (CCK), somatostatin, secretin, glucagon, gastric inhibitory polypeptide (GIP), motilin and neurotensin. In the gastric mucosa, gastrin and somatostatin cells were only found in the pyloric regions, and no other hormonal cell-types were observed. In the intestinal mucosa, the largest number of endocrine cells belonged to the gastrin and glucagon/glicentin cell-types, whereas CCK-33/39 and secretin cells were the least numerous. Numbers of other cell-types were intermediate between these two groups. The gastrin and GIP cells were mostly localized in the proximal portion of the intestine, decreasing in number towards the distal portion. The motilin and CCK-33/39 cells were restricted to the proximal half. The glucagon/glicentin and neurotensin cells were most abundant in the middle portion. The somatostatin and secretin cells, although only present in small numbers, were randomly distributed throughout the intestine. This characteristic distribution of gastrointestinal endocrine cells is discussed in comparison with the distribution patterns of other mammals.
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  • 13
    ISSN: 1432-0878
    Keywords: Blood-testis barrier ; Immune responses ; Tracer studies ; Immunohistochemistry ; Oreochromis niloticus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The blood-testis barrier and its changes following immunization to testis material, were investigated by light- and electron microscopy in a teleost fish, the Nile tilapia Oreochromis niloticus, using horseradish peroxidase and bovine serum albumin as tracers. In the normal testis, histochemistry using horseradish peroxidase revealed that a barrier composed of junctional complexes connecting adjacent Sertoli cells existed around the central lumina of the seminal lobules, and also around the germ-cell cysts containing spermatids at the middle or late phase of chromatin condensation. By contrast, bovine serum albumin was prevented from passing through the basement membrane and could not penetrate any of the spermatogenetic cysts, indicating that the basement membrane may be an ion-selective barrier. In tilapia immunized with allogeneic testis homogenate emulsified in Freund's complete adjuvant, bovine serum albumin could penetrate the spermatogenetic cysts, and horseradish peroxidase was able to pass through the intercellular spaces between Sertoli cells to the region nearer the seminal lobule lumen, due to the junctional complexes becoming loosened. The results suggest that the blood-testis barrier, both junctional complexes and the basement membrane, are broken down during immune responses.
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  • 14
    ISSN: 1432-0878
    Keywords: Cerebellum ; Purkinje cells ; Ectopia ; GABA ; Immunohistochemistry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Intensely stained cells are found in the cerebellar white matter of the vermis and paravermis in adult rats after immunoreaction with an immune serum raised against glutamic acid decarboxylase (GAD). The cells are similar in size to cortical Purkinje cells and three times the size of Golgi cells of the internal granule layer, and have a thick immunopositive cell process emerging from a welldefined cytoplasmic cone. In the cytoplasm, immunoprecipitates are more dense around the nucleus as in normally located Purkinje cells. The morphological appearance of the immunopositive cells suggests that they may be ectopically located Purkinje cells. The soma of the ectopic Purkinje cells is contacted by a few darkly stained terminal boutons. Data indicate that, in spite of the different cellular environment, ectopic Purkinje cells can develop not only the typical morphological pattern already described but also other intrinsic features, such as their typical inhibitory neurotransmitter.
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  • 15
    ISSN: 1432-0878
    Keywords: Corticotropin-releasing factor hormone ; Immunohistochemistry ; Radioimmunoassay ; Hypothalamus ; Scyliorhinus canicula (Elasmobranchii)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The occurrence and localization of immunoreactive corticotropin-releasing factor (CRF) in the brain and pituitary of the elasmobranch fish Scyliorhinus canicula, were studied by means of specific radioimmunoassay and immunohistochemistry using the indirect immunofluorescence method. Brain and pituitary extracts showed a good cross-reactivity with the ovine CRF antiserum, but serial dilutions of tissue samples did not completely parallel the standard curve. Relatively high concentrations of CRF-like material were found within the pituitary, diencephalon, and telencephalon. CRF-like immunoreactive perikarya were observed in the preoptic nucleus and in the nucleus lateralis tuberis. Numerous immunoreactive cells appeared to be of the CSF-contacting type. CRF-like immunopositive fibers were seen to run through the hypothalamus within the ventro-medial floor of the infundibular region. A dense plexus of immunoreactive nerve endings terminated in the median eminence and the neurointermediate lobe of the pituitary. These results indicate that a neurosecretory system containing CRF-like immunoreactivity exists in the brain of elasmobranchs, a group of vertebrates which has diverged early from the evolutionary line leading to mammals. In addition, our data support the notion that a CRF-like molecule is involved in the regulation of corticotropic and melanotropic cell activity in this primitive species of fish.
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  • 16
    ISSN: 1432-0878
    Keywords: Mucosa ; Lymphoid tissue ; Nose ; Development ; Immunohistochemistry ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This study concerns the development of nasal-associated lymphoid tissue in the rat, using immuno- and enzyme-histochemical staining techniques on cryostat sections. Nasal-associated lymphoid tissue is present at birth as a small accumulation of mainly T lymphocytes and non-lymphoid cells; B cells are rare. Distinct areas of T and B cells appear at 10 days after birth; by that time high endothelial venules are also observed. Intra-epithelial lymphocytes are present, most of them being T-helper cells. ED1+ macrophages are seen throughout the tissue. The proportion of ED1+cells does not change during ontogeny. ED2+cells (tissue macrophages) are present predominantly at the border between the lymphoid tissue and the surrounding connective tissue, in all age-groups. ED3+mononuclear cells are scattered throughout the nasal-associated lymphoid tissue of young animals. Later on, the ED3+ cells migrate into the border-area between lymphoid and connective tissue. Ia+ non-lymphoid cells in the nasal lymphoid tissue increase in number during ontogeny. Only a few of them show acid phosphatase activity, indicating that the proportion of classical scavenger macrophages is low. Some of them may be antigen presenting (dendritic) cells. Ia+ dendritic cells also occur between the epithelial cells. Moreover, some epithelial cells express the Ia marker.
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  • 17
    ISSN: 1432-0878
    Keywords: FMRFamide ; Brain ; Neurohypophysis ; Pineal body ; Immunohistochemistry ; Lampetra japonica (Cyclostomata)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Distribution of molluscan cardio-excitatory tetrapeptide Phe—Met—Arg—Phe—NH2 (FMRFamide) was determined by means of immunohistochemistry in the brain and neurohypophysis of the lamprey, Lampetra japonica. Many FMRFamide-like immunoreactive neurons were found in the periventricular nuclear region and in a region near the mammillary recess. Neurons situated in the former region were larger. The immunoreactive cell groups were shown to be located at sites differing from those of the AF-positive cell groups. The fibers of immunoreactive neurons extended in all directions within the brain and towards the spinal cord, some reaching the third ventricle and capillaries. Thus, FMRFamide-like immunoreactive peptides appear to function as neurotransmitters or neuromodulators and possibly also as neurohormones. FMRFamide-like immunoreactive material was rarely observed in the posterior neurohypophysis (neural lobe), but was noted to be present to a limited extent in the caudal part of the anterior neurohypophysis (median eminence). It would thus follow that FMRFamide-like immunoreactive neurons may not necessarily be related to the hypothalamo-neural lobe system, but may possibly be associated with the hypothalamoadenohypophysial system. The pineal body showed no FMRFamide-like immunoreactivity.
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  • 18
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    Cell & tissue research 256 (1989), S. 585-592 
    ISSN: 1432-0878
    Keywords: Axonal retrograde tracing ; Hypothalamus ; Immunohistochemistry ; Methionine-enkephalin ; Septum ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The location of the cells giving rise to the methionine-enkephalin (Met-Enk)-ergic innervation of the lateral septal nucleus has been investigated in the rat by combining immunohistochemistry and retrograde axonal tracing. Small volumes (0.06 μl) of apo-horseradish peroxidase (Apo-HRP) conjugated to wheat-germ agglutinin (WGA) and coupled with colloidal gold particles (WGA-ApoHRP-gold) were injected into the lateral septum. The retrogradely labeled cell bodies were visualized by silver intensification of the gold particles on Vibratome sections that were subsequently processed for immunohistochemistry for Met-Enk. Cells labeled with WGA-ApoHRP-gold were observed in the septal area, throughout the hypothalamus (mainly in the perifornical and lateral nuclei) and in the mesencephalon. The localization of Met-Enk-immunoreactive cells was as previously described. With the exception of a few septal cells close to the injection site, doubly labeled cells were found only in the perifornical nucleus of the hypothalamus. Almost all perifornical magnocellular cells were doubly labeled ipsilateral to the injection site, whereas on the opposite side, only about 25% of the Met-Enk-immunoreactive cells contained WGA-ApoHRP-gold. Other brain regions containing retrogradely labeled or Met-Enk-immunoreactive cells (particularly the raphe nuclei) did not show double-labeled neurons. This study demonstrates, using a new and sensitive technique for specific neurochemical tracing of tracts, that the origin of the Met-Enk-ergic innervation of the rat lateral septal nuclei lies in the magnocellular perifornical nuclei of the hypothalamus. The precise involvement of this pathway in limbic functions remains to be determined.
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  • 19
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    Cell & tissue research 257 (1989), S. 657-660 
    ISSN: 1432-0878
    Keywords: Pituitary ; Intermediate lobe follicles ; Immunohistochemistry ; α-MSH ; Agranular cells ; Meriones unguiculatus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The Mongolian gerbil (Meriones unguiculatus) contains abundant follicles throughout the intermediate lobe (IL) of the pituitary gland in the adult animal. The mode of follicle formation, the nature of the follicle building cells and the distribution of follicles were investigated in semithin sections of the gerbil IL. The sections were stained conventionally, or immunohistochemically with antibodies directed against α-melanocyte stimulating hormone (α- MSH). Follicular cells were constantly α-MSH-negative, and resembled the marginal cells lining the hypophyseal cleft with regard to their cytological and immunohistochemical properties. Moreover, follicular cells appeared to be derived from strands of marginal cells that regularly invaginated deep into the IL. Both follicular and marginal cells often made up cellular clusters. This process coincided with follicle formation and the generation or transport of the colloidal content found inside follicles and the hypophyseal cleft. Although the non-secretory cells of the IL obviously constituted one major source of pituitary colloid in the gerbil, α-MSH-positive secretory cells, which occasionally were found to be discharged into the cleft cavity, might contribute to the colloidal contents.
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  • 20
    ISSN: 1432-0878
    Keywords: Insect nervous system ; Cholecystokinin-like peptide ; Immunohistochemistry ; Radioimmunoassay ; Aeschna cyanea (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Gastrin/cholecystokinin (gastrin/CCK)-like immunoreactivity has been detected in the brain, suboesophageal ganglion and corpora cardiaca of the larva of Aeschna cyanea by radioimmunoassay and immunohistochemistry, by use of two antisera raised against the sulfated (CCK-8S) and the unsulfated form (CCK-8NS) of the carboxyl terminal octapeptide. Numerous immunoreactive neurons were demonstrated in the protocerebrum (exclusive of optic lobes) and suboesophageal ganglion where 20 and 15 symmetrical clusters of reactive cells, respectively, were observed. Immunoreactive cells also occurred in the tritocerebrum, the optic lobes and the frontal ganglion. In the corpora cardiaca, gastrin/CCK-like material was found both within intrinsic cells and axon terminals. RIA measurements support the immunohistochemical results in so far as large amounts of gastrin/CCK-like material were detected in the brain, corpora cardiaca and suboesophageal ganglion complex. Both boiling water-acetic acid- and methanol-extraction procedures were performed. Comparisons of the results lead to the conclusion that a large part of the gastrin/CCK-like material occurs as small molecules. Immunohistochemical procedures performed on material fixed in a solution of picric acid-paraformaldehyde demonstrated differences in the immunoreactivity of the tested antisera. First, the immunohistochemical reaction was always more pronounced when the CCK-8NS antiserum was used instead of the CCK-8S antiserum, which may be interpreted by a lower affinity of the latter. In the second place, some neurons strongly stained by the CCK-8NS antiserum were only very faintly if at all stained by the CCK-8S antiserum, which may mean that different peptides or at least distinct forms of the same precursor are detected.
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  • 21
    ISSN: 1432-0878
    Keywords: Transplantation ; Serotonin ; Tyrosine hydroxylase ; Immunohistochemistry ; Leptomeninges ; Rat (Wistar)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pieces of fetal midbrain raphe containing serotonergic and dopaminergic neurons were transplanted into the leptomeningeal tissue (see Fig. 3) of adult host rats that had previously been denervated by treatment with 5,6-dihydroxytryptamine. One, 2 and 5 months after transplantation, the rate of neuronal survival in the grafted tissue and the extent of axonal outgrowth into the host brain were studied by use of serotonin and tyrosine hydroxylase (TH) immunohistochemistry. The survival rate of the grafts in the 1-month group was approximately 70%. Neurons containing either serotonin or catecholamine were demonstrated by means of immunocytochemical procedures in the grafts. Two and 5 months after transplantation, serotonin-immunoreactive nerve fibers were densely distributed throughout the graft tissue, while TH-immunoreactive fiber elements were restricted to an area near the somata of TH-positive neurons. Numerous serotonin-immunoreactive fibers derived from the transplant were found in the leptomeningeal tissue surrounding the graft, on the wall of neighboring blood vessels, and also in the adjacent parenchyma of the host brain. Outgrowing TH-immunoreactive nerve fibers were not observed in the host brain, although such elements occurred in the leptomeningeal tissue and the wall of the larger blood vessels. These results suggest that the serotonergic and catecholaminergic (dopaminergic) neurons located in transplants of the raphe nuclei show different patterns when reinnervating the host tissue.
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  • 22
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    Cell & tissue research 256 (1989), S. 645-648 
    ISSN: 1432-0878
    Keywords: Mammosomatotropes ; Adenohypophysis ; Electron microscopy ; Immunohistochemistry ; Mouse (SMA)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Two types of mammosomatotropes (MS), the small-granule and vesicle-granule MS, were detected in mouse adenohypophysis by electron microscopy and immunohistochemistry. Both cell-types were immunoreactive to prolactin (PRL) and growth hormone (GH) antisera. The small-granule MS contained small, round, solid secretory granules about 100 nm in diameter, and were smaller than the classical GH and PRL cell-types. The vesicle-granule MS contained secretory granules like cored vesicles, and were larger than classical GH and PRL cells. Small-granule MS were immunoreactive to both PRL and GH antisera in the same region of the cell cytoplasm; the vesicle-granule MS, however, were immunoreactive to only PRL antiserum in most cytoplasmic areas, and a positive response to both PRL and GH antisera was confined to only certain small areas.
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  • 23
    ISSN: 1432-0878
    Keywords: Monoclonal antibody ; FMRFamide ; Immunohistochemistry ; Smooth muscle ; Nervous system ; Podocoryne carnea (Cridaria)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A mouse monoclonal antibody was prepared by using homogenized fragments of crude umbrella material of the hydromedusa Podocoryne carnea as an antigen. The selected clone produced an IgG (mAb sm-1) which decorated smooth muscle cells of hydrozoans. Immunohistochemical testing of mAb sm-1 on whole-mount preparations revealed reactivity with a cytoplasmic, formaldehyde-resistant antigen present in the smooth muscle cells, but absent in all other cell-types. The antibody can therefore be used as a selective and highly sensitive marker to trace the pattern of the smooth muscle system in hydrozoans. The tight association between smooth muscle cells and nerve cells which show FMRFamide-like immunoreactivity can be demonstrated in whole-mount preparations of the hydromedusa Podocoryne carnea with a polyclonal anti-FMRFamide antiserum and in double-labelling experiments.
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  • 24
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    Cell & tissue research 256 (1989), S. 27-34 
    ISSN: 1432-0878
    Keywords: Kidney ; Endothelium ; Monocyte ; Von Willebrand factor ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary To clarify the structural base of immune response occurring in the kidney, we investigated the antigenic and functional properties of vascular endothelial cells. Peritubular capillary endothelial cells exhibited the same immuno-histochemical characteristics (OKM5-positive, HLA-DR-positive, Factor VIII/von Willebrand factor antigen-negative, Interleukin 1-positive) as a peripheral blood macrophage subset capable of presenting soluble antigens and triggering the autologous mixed lymphocyte reaction. On the other hand, endothelial cells of glomerular capillary loops, considered to be involved in blood coagulation, were OKM5-negative, HLA-DR-positive, Factor VIII/von Willebrand factor antigen-positive, Interleukin 1-positive. Thus the results of this study suggest that vascular endothelial cells in different anatomic compartments of the kidney express surface antigens heterogenously and may play different roles in the immune reaction.
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  • 25
    ISSN: 1432-0878
    Keywords: Gut ; Immunohistochemistry ; Neurons ; Serotonin ; Bufo marinus (Anura)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The gut of the toad, Bufo marinus, was examined for evidence of enteric neurons containing 5-hydroxytryptamine-like immunoreactivity. Such neurons were absent from the stomach. They were present in the small intestine, with processes confined to the myenteric plexus. Immunoreactive nerve cell bodies lay on branches of the pelvic nerves supplying the large intestine; fibres were found in the submucosa of the posterior large intestine and in the muscularis externa of the anterior large intestine. It is concluded, on morphological grounds, that the neurons in the small intestine are interneurons, whereas those in the large intestine are postganglionic parasympathetic motoneurons.
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  • 26
    ISSN: 1432-0878
    Keywords: Follicular dendritic cells ; B-lymphocytes ; Follicular structure ; Immunohistochemistry ; Cell culture ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphological and phenotypical features of multicellular complexes formed by follicular dendritic cells and lymphocytes (FDC-LC) isolated from human hyperplastic tonsils and adenoids are described. FDC-LC obtained with this procedure were morphologically and immuno-phenotypically heterogeneous. In one type of FDCLC, probably obtained from germinal centers, the lymphocytes exhibited ultrastructural features of centroblasts and centrocytes. In a second type, likely derived from follicular mantles, the enclosed lymphocytes were small in size and characterized by a condensed chromatin pattern. Similar heterogeneity was observed by immuno-phenotypical analysis, which revealed a prevalence of IgD+, CD3-, MT2+ small lymphocytes in a high proportion of FDC-LC. Both types of FDC-LC contained desmoplakin immunoreactivity in a typical punctate pattern corresponding to intercellular junctions when tested with a specific antibody. These findings confirm the importance of FDC in maintaining the follicular structure and also suggest that the different zones forming lymphoid follicles (mantle zone and germinal center) are formed by lymphocytes gathered in single “domains” by cytoplasmic processes of FDC. These domains have strong resistance to mechanical stress, such as that used in isolation procedures. FDC-LC have also been maintained as organized multicellular clusters for short periods (more than 48 h) in agarose gel cultures.
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  • 27
    ISSN: 1432-0878
    Keywords: Enteroendocrine cells ; Immunohistochemistry ; Bombesin ; Enkephalin ; Gastrin/CCK ; 5-HT ; Neuropeptide Y ; Neurotensin ; Substance P ; VIP ; Intestine ; Starvation ; Leuciscus idus melanotus ; Poecilia reticulata (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Endocrine cells containing bombesin-, enkephalin-, gastrin/CCK-, 5-HT-, and substance P-like material were demonstrated in the alimentary tract of Poecilia reticulata and Leuciscus idus melanotus. Endocrine cells with neuropeptide-Y-like immunoreactivity were found only in P. reticulata, those with VIP-like immunoreactivity only in L. idus melanotus. Gut nerves showing bombesin-, G/CCK-5-HT-, neurotensin-, substance P-and VIP-like immunoreactivity were observed in both species investigated, enkephalin- and neuropeptide Y-like immunoreactivity in P. reticulata alone. The distribution and amount of endocrine cells and nerves along the gut as visualized with the appropriate antisera varied in both teleosts. Histologically, the intestinal tract of these stomachless fish can be divided into three regions. A large number of endocrine cells with VIP-like immunoreactivity was noted in the rectum of L. idus melanotus. Endocrine cells containing bombesin-, enkepha-lin- and substance P-like material were found only in intestinal parts I and II in L. idus melanotus. Neuropeptide Y-like immunoreactivity was absent from intestinal part I of P. reticulata. The influence of starvation on the immunoreactivity of nerves and enteroendocrine cells in the teleost intestine was examined. After a starvation period of more than 6 weeks, no alterations were observed either in the appearance or amount of nerve and endocrine cell immunoreactivity.
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  • 28
    ISSN: 1432-0878
    Keywords: Neuropeptide Y (NPY) ; Catecholamines ; Cardiovascular system, innervation ; Immunohistochemistry ; Elasmobranchs (Raja erinacea, Raja radiata, Squalus acanthias) ; Teleosts (Gadus morhua, Salmo gairdneri)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of nerves showing neuropeptide Y (NPY)-like immunoreactivity in the cardiovascular system of elasmobranchs and teleosts has been investigated. Two species of teleosts, the rainbow trout (Salmo gairdneri) and the Atlantic cod (Gadus morhua), and three species of elasmobranchs, the spiny dogfish (Squalus acanthias), the little skate (Raja erinacea) and the starry ray (Raja radiata), were used in this study. An innervation of the cardiovascular system by an NPY-like substance was found only in the two species of Raja. A rich innervation was encountered in these skates, with the highest density of fibres in the wall of the ventricle, the conus arteriosus, the coeliac artery and smaller mesenterial vessels. In the vessels, the fibres formed a plexus at the adventitio-mediol border. Few fibres were found in the walls of the dorsal aorta, the sinus venosus and the atrium, and no fibres were observed in the walls of the ventral aorta. Falck-Hillarp fluorescence histochemistry showed the presence of a rich innervation of arteries and arterioles of the gut by catecholamine-containing nerve fibres.
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  • 29
    ISSN: 1432-0878
    Keywords: Subcommissural organ ; Intermediate filaments ; Glial fibrillary acidic protein (GFAP) ; Vimentin ; Immunohistochemistry ; Meriones unguiculatus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The chemical composition of intermediate filaments (IF's) in the ependyma of the subcommissural organ (SCO) of the Mongolian gerbil (Meriones unguiculatus) was investigated immunohistochemically in paraffin-embedded tissue. Antibodies against glial fibrillary acidic protein (GFAP), vimentin, neurofilament proteins and cytokeratins were used. Only GFAP and vimentin were detected in the non-specialized diencephalic ependyma and in the ependymocytes of the SCO. Staining could be observed in apical and basal processes of the SCO-cells. The latter processes extended into the posterior commissure up to the subpial surface, thus establishing a well-developed leptomeningeal route of ependymal projections. In contrast to the homogeneous vimentin-labeling, the SCO was particularly immunoreactive for GFAP in its lateral aspects and in the supraand precommissural parts. The coexpression of GFAP and vimentin in a subclass of SCO-ependymocytes was demonstrated on differentially immunostained semithin sections. The present study confirms the glial nature of the SCO-ependyma, which has been a matter of debate recently. It appears from this investigation that the high degree of secretory activity in the SCO does not necessarily lead to the disappearance of glial IF proteins. Moreover, the SCO-cells belong to the expanding group of mature astroglia, which is characterized by coexpression of GFAP and vimentin. The morphological similarity between SCO-ependymocytes and tanycytes is underscored by their common immunoreactivity against these two IF proteins. In view of the absence of GFAP from the rat SCO, interspecific differences must be considered in the evaluation of the IF protein composition.
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  • 30
    ISSN: 1432-0878
    Keywords: Ovary ; Immunohistochemistry ; Plasminogen activator ; Ovulation ; Rat (Sprague-Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The observation that tissue-type plasminogen activator (tPA) activity increased dramatically in preovulatory follicles has led to the hypothesis that plasminogen activation is causally related to follicle rupture. With immunohistochemistry, we have studied the appearance of tPA in ovaries of immature rats induced to ovulate and in adult cycling rats. Treatment of immature female rats with a single dose of pregnant mare serum gonadotropin (PMSG) induced follicular maturation. A subsequent human chorionic gonadotropin (hCG) injection resulted in follicle rupture 12–14 h later. PMSG treatment alone did not induce appearance of tPA-immunoreactive cells in any ovarian compartment. After hCG stimulation, however, theca cells, granulosa cells, and oocytes of pre- and postovulatory follicles displayed distinct tPA immunoreactivity. Fibroblastlike cells in the theca layers and tunica albuginea of the follicle apex also demonstrated localized cytoplasmic tPA reactivity. In addition to tPA synthesis in preovulatory follicles, hCG also induced tPA staining in the theca (but not granulosa) layers of non-ovulatory follicles. At 24 h after hCG treatment, there was a marked tPA staining in developing corpora lutea, ovulated ova, and oviductal epithelium. Ovaries from regularly cycling adult rats displayed a similar ovulation-related pattern of tPA immunostaining. The appearance of tPA in different cell types of the preovulatory follicle and in the fibroblast-like cells at the follicle apex, strengthens the hypothesis of a direct involvement of tPA in follicle rupture. Presence of tPA in postovulatory oocytes, cumulus cells, and surrounding oviductal epithelium may also indicate a role for tPA in the transfer of eggs in the oviduct.
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  • 31
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    Cell & tissue research 257 (1989), S. 23-28 
    ISSN: 1432-0878
    Keywords: Melatonin ; Immunohistochemistry ; Radioimmunoassay ; Pineal gland ; Mink, Mustela vison
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An antiserum raised against N-amino-3-propyl melatonin bound to a protein carrier was used to visualize melatonin by immunohistochemistry and to measure melatonin concentration by radioimmunoassay in the pineal gland of intact mink females killed throughout the 24 h cycle and females killed after a bilateral ablation of the cervical superior ganglion. Melatonin immunoreactivity revealed by immunofluorescence or by the peroxidase-antiperoxidase complex was observed in the cytoplasm of presumed pinealocytes of all the females. Circadian changes in pineal melatonin content were not visualized by immunohistochemistry; furthermore, immunoreactivity was also present in the pineal gland of the ganglionectomized females. However, the melatonin content measured by radioimmunoassay was significantly higher in the pineal gland from intact females killed during the night compared with that of intact females killed during the day or of ganglionectomized females. The discrepancy between the results obtained using the two methods may arise because immunohistochemistry can detect very small amounts of melatonin.
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  • 32
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    Cell & tissue research 257 (1989), S. 149-153 
    ISSN: 1432-0878
    Keywords: Calbindin ; Brachial spinal cord ; Dorsal root ganglion ; Immunohistochemistry ; Domestic fowl
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of the vitamin D-dependent calcium-binding protein, calbindin, was mapped in the brachial spinal cord and in the 15th dorsal root ganglion of the domestic fowl, using fluorescence immunohistochemistry. Cell somata of the dorsal root ganglion ranged in area from 200 μm2 to 2000 μm2. Sixteen percent of cell bodies displayed calbindin immunoreactivity. Reactivity occurred in both the small and large sensory neurons. These were randomly distributed within each ganglion. In the spinal cord, calbindin immunoreactivity was intense in Lissauer's tract, and in nerve fibres and nerve cell bodies within laminae 1 to 3 of the dorsal horn. Scattered varicose fibres were observed in laminae 4 to 7. Immunoreactivity was intense in laminae 10 where nerve fibres formed a meshwork around the central canal. Immunoreactive perikarya were occasionally observed in the outer region of lamina 10 and between laminae 8 and 9. The perikarya of the large motoneurons of lamina 9 were not reactive although they were enmeshed in calbindin-immunoreactive fibres.
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  • 33
    ISSN: 1432-0878
    Keywords: Neuromedin U ; Enteric nervous system ; Intestine, small ; Immunohistochemistry ; Neuropeptides ; Guinea-pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neuromedin U immunoreactivity was located histochemically in the guinea-pig small intestine. Projections of immunoreactive neurons were determined by analysing patterns of degeneration following nerve lesions. The co-localization of neuromedin U immunoreactivity with immunoreactivity for substance P, neuropeptide Y, vasoactive intestinal peptide and calbindin was also investigated. Neuromedin U immunoreactivity was found in nerve cells in the myenteric and submucous plexuses and in nerve fibres in these ganglionated plexuses, around submucous arterioles and in the mucosa. Reactive fibres did not supply the muscle layers. Most reactive nerve cells in the myenteric ganglia had Dogiel type-II morphology and in many there was co-localization of calbindin, although some Dogiel type-II neuromedin U neurons were calbindin negative. Lesion studies suggest that these myenteric neurons project circumferentially to local myenteric ganglia. Projections from myenteric neurons also run anally in the myenteric plexus, while other projections extend to submucous ganglia, and still further projections run from the intestine to provide terminals in the coeliac ganglia. In the submucous ganglia neuromedin U was co-localized in three populations of nerve cells: (i) those with vasoactive intestinal peptide immunoreactivity, (ii) neurons containing neuropeptide Y, and (iii) neurons containing substance P. Each of these populations sends nerve fibres to the mucosa. Neuromedin U immunoreactivity is thus located in a variety of neurons serving different functions in the intestine and therefore probably does not have a single role in intestinal physiology.
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  • 34
    ISSN: 1432-0878
    Keywords: Spleen ; Periarterial lymphoid sheath (PALS) ; Macrophage subpopulations ; Microenvironment ; B-lymphocytes ; Immune response ; Cell proliferation ; Immunohistochemistry ; Rat (DA)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In an attempt to reveal the role of antigen-laden marginal metallophil (MM) and other macrophages in the intrasplenic immune response of a specific B-cell lineage to a thymus-independent type-2 antigen (Ficoll conjugated with fluorescein isothiocyanate), simultaneous immuno-histological observations of the involved cells were performed in the rat. By newly established methods of double or triple immunostainings, time-kinetics of the following parameters were studied and compared: (1) the antigen, (2) the specific antibody-forming cells (AFC) directed to the fluorescein-isothiocyanate determinant, (3) proliferating cells labeled with 5-bromo-2′-deoxyuridine (BrdU), and (4) macrophage subpopulations recognized by monoclonal antibodies (ED2 and ED3). The antigen localized stably not only in the marginal-zone macrophages but also in the MM except around the follicular area. The increase of BrdU-positive cells was observed from day 2 up to day 4 after antigen injection mostly in the periphery of the periarterial lymphoid sheath (outer PALS), which indicated antigen-induced proliferation. As a novel finding, the majority of AFC, both BrdU-positive and -negative, were either closely associated with the antigen-laden MM, or forming cell clusters with ED2-positive macrophages in the outer PALS. In contrast, there were very few AFC in juxtaposition to antigen-free MM in the follicular area or the antigen-laden marginal zone macrophages. The results led to the proposal of a hypothesis that the antigen-laden MM together with ED2-positive macrophages constitute an immunoproliferative microenvironment for the plasmacellular reaction by accumulating the antigen-specific B-cell lineage and promoting these cells to differentiate into the AFC and to proliferate in the outer PALS.
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  • 35
    ISSN: 1432-0878
    Keywords: Corpuscles of Stannius ; Hypocalcin ; Immunohistochemistry ; Carassius auratus ; Hippoglossoides elassodon ; Salmo gairdneri
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In order to identify the cell-type responsible for the production of hypocalcin (the recently isolated hypocalcemic hormone of teleost fish), the corpuscles of Stannius (CS) of trout, flounder and goldfish, were immunocytochemically stained with antisera raised against trout hypocalcin. The secretory granules of the type-1 cells of the CS, considered to be the hypocalcin-producing cells, showed intense immunoreactivity in all species examined. However, in trout and flounder, the secretory granules produced by the type-2 cells, which have been suggested to represent a functionally different cell-type, also showed an intense immunoreactivity. In goldfish, no type-2 cells were observed. We tentatively conclude that type-1 and type-2 cells represent structurally different forms of the same functional cell-type.
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  • 36
    ISSN: 1432-0878
    Keywords: Heart-conducting system ; Vasoactive intestinal polypeptide (VIP) ; Neuropeptide Y ; Dopamine-betahydroxylase ; Immunohistochemistry ; Cow
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary It is not known whether VIP coexists with other neuropeptides or neurotransmitters in the heart. In the present study, the distribution of nerve fibers showing VIP-like immunoreactivity (VIP-LI) in various parts of the bovine heart was compared with that of fibers possessing neuropeptide Y (NPY)- and dopamine-beta-hydroxylase (DBH)-LI. It was found that fibers showing VIP-LI most regularly occurred in the regions of sinuatrial and atrioventricular nodes and intracardiac ganglia, the nerve fibers being associated with nodal and ganglionic cells and arterial walls. Furthermore, it was observed that almost all fibers showing VIP-LI also exhibited NPY-LI. The fibers displaying VIP-LI occurred close to fibers endowed with DBH-LI, and on some occasions it appeared that varicosities showing immunolabeling for VIP also displayed DBH-LI. VIP- and NPY-LI, but not DBH-LI, was detected in some of the intracardiac ganglionic cells. The observations are discussed in relation to the previously known distribution and function of VIP in the heart and other organs. Further studies examining the effects of VIP and NPY in the heart should take into account possible interactions between these two peptides.
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  • 37
    ISSN: 1432-0878
    Keywords: Gastrin ; Gastrin-releasing peptide ; Bombesin ; Stomach ; Autonomic innervation ; Immunohistochemistry ; Guinea pig ; Rat ; Dog ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The relationship between bombesin-like immunoreactive (bombesin-LI) nerve fibres and gastrin-LI G-cells was examined in gastric antral mucosa from guineapig, rat, dog and man using a double-labelling fluorescence immunohistochemical technique. The greatest density of bombesin-LI nerve fibres was found within the basal mucosa in all species and the density of innervation decreased towards the luminal surface. Most G-cells were in a band occupying approximately the middle third of the mucosa. The proportion of G-cells found within a distance of 2 μm from bombesin-LI nerve fibres was low in all species (6% in the guinea-pig, 22% in the rat, 14% in the dog, and 9% in the human). It is proposed that the neuropeptide released from bombesin-LI antral mucosal nerve fibres traverses distances of greater than several μm to reach the target G-cells. This may be achieved by passage through the mucosal microcirculation.
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  • 38
    ISSN: 1432-0878
    Keywords: Corticotropin-releasing factor (CRF) ; Immunohistochemistry ; Neurosecretory system ; Hypothalamus ; Nucleus striae terminalis ; European starling (Sturnus vulgaris) ; Song sparrow (Melospiza melodia)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Corticotropin-releasing factor (CRF) was localized in the brains of two passerine species, the European starling (Sturnus vulgaris) and the song sparrow (Melospiza melodia), by means of immunohistochemistry. The hypothalamic distribution of this peptide in these species includes a complex of immunoreactive perikarya observed in the paraventricular nucleus (PVN), in both its medial and lateral divisions. Nerve fibers were also seen running from these areas to the anterior median eminence (AME) where a terminal field is apparent. A wide variety of extra-hypothalamic nuclei containing CRF-immunoreactive cells and fibers were identified. An apparent CRF terminal field can be visualized in the lateral septum. A dense fiber plexus is present in the nucleus accumbens (Ac) and more caudally in the nucleus of the stria terminalis (nST). In colchicinepretreated animals, it was revealed that these areas also contain CRF-stained perikarya. The pattern of CRF immunoreactivity in the Ac-nST complex is continuous, with no distinction apparent between the nuclei. The medial preoptic area (mPOA) and the adjacent diagonal band of Broca contain CRF-fibers, while cells are apparent in the mPOA. In the mesencephalon, cells were visualized in the midbrain central gray; a terminal field and scattered positively stained perikarya were found in areas more ventral to the central grey that are adjacent to the third cranial nerve. Scattered cells were also seen at the border of the nucleus intercollicularis-nucleus mesencephalicus lateralis, pars dorsalis complex. In contrast to mammalian studies, no immunoreactive nerve fibers or perikarya were observed in telencephalic areas homologous to the mammalian neocortex. These studies confirm the presence of a CRF path-way regulating pituitary function and suggest a broad role played by CRF as a neuromodulator or neurotransmitter in autonomic and possibly behavioral activities in these species.
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  • 39
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    Cell & tissue research 257 (1989), S. 263-268 
    ISSN: 1432-0878
    Keywords: Retinol ; Vacuoles ; Immunohistochemistry ; Plasma proteins ; Hepatocytes ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The vacuoles occurring in rat hepatocytes after intraportal injection of retinol (33 or 67 μg) were examined immunohistochemically using respective antibodies against rat albumin, human retinol-binding protein, human ceruloplasmin, human α 1-antitrypsin, human transferrin, and human prealbumin as representative plasma proteins. The occurrence of the vacuoles reached a numerical maximum 30 min after injection of 67 μg retinol, followed by a temporal decrease. Hepatocytes from control rats, which had been intraportally injected with either blood plasma diluted to 2/3 concentration or with retinol palmitate solvent (castor oil) dissolved in blood plasma, showed immunoreactive fine granules without the occurrence of vacuoles in the cytoplasm. Identical vacuoles in serial sections appeared immunohistochemically either immunoreactive or non-immunoreactive for all the antibodies used, with rare exceptions. The occurrence of several rare exceptions suggested that 2 kinds of vacuoles might be formed in different cytoplasmic compartments. A zonal distribution of vacuoles was apparent in the hepatic laminae (or acini) within the liver lobules. The vacuoles were predominantly distributed in zone 2, and to a lesser extent in zone 3 and zone 1 in that order.
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  • 40
    ISSN: 1432-0878
    Keywords: Neuropeptide Y ; Anglerfish peptide YG ; Brain ; Pancreas, endocrine, innervation ; Immunohistochemistry ; Radioimmunoassay ; High performance liquid chromatography ; Anglerfish, Lophius americanus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Results from a previous report demonstrate that more than one molecular form of neuropeptide Y-like peptide may be present in the islet organ of the anglerfish (Lophius americanus). Most of the neuropeptide Y-like immunoreactive material was anglerfish peptide YG, which is expressed in a subset of islet cells, whereas an additional neuropeptide Y-like peptide(s) was localized in islet nerves. To learn more about the neuropeptide Y-like peptides in islet nerves, we have employed immunohistochemical and biochemical methods to compare peptides found in anglerfish islets and brain. Using antisera that selectively react with either mammalian forms of neuropeptide Y or with anglerfish peptide YG, subsets of neurons were found in the brain that labelled with only one or the other of the antisera. In separate sections, other neurons that were labelled with either antiserum exhibited similar morphologies. Peptides from brains and islets were subjected to gel filtration and reverse-phase high performance liquid chromatography. Radioimmunoassays employing either the neuropeptide Y or peptide YG antisera were used to examine chromatographic eluates. Immunoreactive peptides having retention times of human neuropeptide Y and porcine neuropeptide Y were identified in extracts of both brain and islets. This indicates that peptides structurally similar to both of these peptides from the neuropeptide Y-pancreatic polypeptide family are expressed in neurons of anglerfish brain and nerve fibers of anglerfish islets. The predominant form of neuropeptide Y-like peptide in islets was anglerfish peptide YG. Neuropeptide Y-immunoreactive peptides from islet extracts that had chromatographic retention times identical to human neuropeptide Y and porcine neuropeptide Y were present in much smaller quantities. These results are consistent with the hypothesis that peptides having significant sequence homology with human neuropeptide Y and porcine neuropeptide Y are present in the nerve fibers that permeate the islet.
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  • 41
    ISSN: 1432-0878
    Keywords: Monoclonal islet antibodies ; Thyroid C-cells ; Differentiation antigens ; Immunohistochemistry ; Cow, Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Thyroid C-cell reactivity to 15 monoclonal antibodies raised against a series of pancreatic islet cells (H[human]ISL, B[bovine]ISL and R[rat]ISL) was evaluated using an indirect immunoperoxidase technique on frozen thyroid sections. Of the monoclonal anti-islet cell antibodies, five reacted specifically with bovine C-cells or human hyperplastic and neoplastic C-cells but not with follicular cells. Two monoclonal antibodies of the bovine series showed strong immunoreactivity with C-cells and only a weakly positive immunostaining of follicular cells. Five monoclonal antibodies reacted with both thyroid C-cells and follicular cells, whereas 3 monoclonal anti-islet cell antibodies did not stain any cell type of the thyroid. In human medullary carcinomas, calcitonin- and somatostatin-producing neoplastic cells were immunoreactive with the same monoclonal antibodies as were normal human C-cells. The protein bands identified by the monoclonal antibodies in human medullary carcinomas had the same molecular weight as those from pancreatic islet extracts. Our study demonstrates the presence of similar differentiation antigens on thyroid C-cells and pancreatic islet cells; this further illustrates common modes of differentiation and specialisation of these embryologically different members of the dispersed neuroendocrine system. The crossreactivity of seven of the monoclonal antibodies investigated with follicular epithelium of the thyroid suggests the existence of common antigenic determinants in different endocrine organs and may partly explain the multiple organ autoimmune response found in patients with polyendocrine diseases.
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  • 42
    ISSN: 1432-0878
    Keywords: Placenta ; Immunoglobulin G ; Endocytosis ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Endogenous immunoglobulin-G was localised in ultrathin frozen sections of human term placenta by use of an indirect immuno electron-histochemical methodology. Immunoreactivity of endogenous IgG to rabbit anti-human immunoglobulin-G antibody was visualised by use of protein-A — colloidal gold complex. Gold marked the syncytiotrophoblast in both coated and uncoated regions of the apical plasmalemma, in vesicles and multivesicular bodies, and in vesicles near the basal plasmalemma. Immunoreactivity was also seen in the interstitial space between the trophoblast and the fetal endothelial layer as well as in various types of vesicles within the endothelial cells. No immunoreactivity was seen in the intercellular clefts of the endothelium. The pattern of localisation observed is consistent with receptor-mediated uptake of immunoglobulin-G into the syncytiotrophoblast of the human placenta followed by release into the interstitial space and then vesciular transport through the endothelium.
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  • 43
    ISSN: 1432-0878
    Keywords: Neuropeptides ; Immunohistochemistry ; Swimbladder ; Gas gland ; Gadus morhua ; Ctenolabrus rupestris ; Anguilla anguilla ; Salmo gairdneri (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation of the swimbladder in four different teleost species has been studied by the use of immunohistochemical methods. The teleosts examined belong to two different groups regarding their swimbladder morphology: physoclists (the cod, Gadus morhua and the goldsinny wrasse, Ctenolabrus rupestris) and physostomes (the eel, Anguilla anguilla and the rainbow trout, Salmo gairdneri). Vasoactive intestinal polypeptide-like immunoreactivity was demonstrated in nerves of the swimbladder walls of all four species, and in the gas glands of the cod and the goldsinny wrasse. Substance P-like immunoreactivity was shown in swimbladders of the cod, eel and rainbow trout but not the goldsinny wrasse. Immunoreactivity to met-enkephalin antiserum was revealed in the swimbladder walls of the eel and the goldsinny wrasse, while neurotensin-like immunoreactivity was present in the goldsinny wrasse and rainbow trout swimbladders. Neurotensin-like immunoreactivity was also seen in the gas gland of the goldsinny wrasse. 5-Hydroxytryptamine immunoreactivity was found in endocrine cells in the pneumatic duct of the eel and in the swimbladder walls of the goldsinny wrasse and the rainbow trout. In conclusion, all teleosts examined showed a very close resemblance in the peptidergic/tryptaminergic innervation of the swimbladder to that of the gut, inasmuch as the immunoreactivity present in the swimbladders always occurred in the gut of the same species.
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  • 44
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    Plant systematics and evolution 165 (1989), S. 227-237 
    ISSN: 1615-6110
    Keywords: Angiosperms ; Eucalyptus ; Eudesmieae ; Floral morphology ; calyx ; corolla ; operculum ; growth ; allometry ; convergence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In theEudesmieae B eucalypts and inEucalyptus caesia, the perianth of the mature flower consists of a single, anatomically continuous, opercular structure that is crowned by the tips of the original free and separate calycine and corolline whorls. Ontogenetic and comparative evidence supports the hypothesis that this operculum is mostly corolline in composition, and that the calycine parts have been elevated distally onto the dorsal surface. In theEudesmieae B eucalypts this condition appears to be due to precocious initiation of the corolline primordia, followed by expansion and continuity of their growth centres which incorporates the areas at or below the base of the still differentiating calycine whorl. InEucalyptus caesia the corolline primordia are not precocious, but a similar situation is effected by a seemingly retarded increase in receptacle diameter relative to lateral expansion of the corolline growth centre(s). In these two examples the same final perianth form apparently derives from two different sets of growth processes which, nonetheless, result in the same allometric relationships within the developing flower. Although identical at maturity, the operculum form in these two taxa is best described in terms of convergence, rather than homology.
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  • 45
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    Acta mechanica Sinica 5 (1989), S. 109-117 
    ISSN: 1614-3116
    Keywords: stability ; boundary layer ; compliant wall
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The stability characteristics of laminar boundary layers over compliant walls was studied by the linear theory. Unlike the previous authors, the coupled motion of the fluid and solid was required to satisfy the continuity conditions of both the velocity and stress at the interface. Results of calculations show that as the speed ratio or density ratio exceeds a certain threshold value, the two types of unstable waves will no longer be distinguishable, and the tangential component of the disturbance stress is no longer negligible. So the neglect of it, as the previous authors did, is unjustified.
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  • 46
    ISSN: 1573-5176
    Keywords: cyanobacteria ; blue-green algae ; biosynthesis ; growth ; gamma linolenic acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The total lipid and fatty acid content ofSpirulina platensis UTEX 1928 was 7.2 and 2.2% respectively of cellular dry weight under controlled conditions supporting high growth rates. With increases in irradiance from 170 to 870 μmol photon m−2 s−1, growth rate increased, total lipid decreased, and fatty acid composition was unaffected. At 1411 μmol photon m−2 s−1, total lipid increased slightly and percent composition of the fatty acid gamma linolenic acid increased. Growth and total lipid content ofS. platensis were affected by changes in growth temperature from 25 to 38 °C. With increased growth rate, total lipid content increased. This suggests that the storage of carbon increases at temperatures supporting high growth rates. The degree of saturation increased with temperature. Although the percent composition of gamma linolenic acid was higher at lower growth temperature, production was still primarily a function of growth rate. The effect of temperature on fatty acid content and degree of saturation was of secondary importance. Nitrogen starvation increased total lipid content but decreased fatty acid content as a percentage of dry weight; composition of the fatty acids was unaffected. N-starvation appeared to suspend synthesis of long chain fatty acids inS. platensis, suggesting that some other compound stores fixed carbon when nitrogen is limiting. It was concluded that fatty acid production inS. platensis is maximized by optimizing culture conditions for growth.
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  • 47
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    Aquatic ecology 23 (1989), S. 73-83 
    ISSN: 1573-5125
    Keywords: model ; fish ; vegetation ; eutrophication ; stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A simple mathematical model was constructed, describing the relationships between pike, bream, aquatic macrophytes and the nutrient loading of shallow lakes. The model is analyzed with the use of zero-isoclines. It is concluded that, over a certain range of nutrient concentrations, the ecological relations incorporated in the model can give rise to the existence of two alternative stable equilibria;viz. a turbid bream-dominated one, and a clear state in which pike and aquatic vegetation are abundant. Under oligotrophic conditions, the clear-water state represents the only stable equilibrium; however, at high nutrient levels, the clear state is absent, or only locally stable. The response of the model to both increase and decrease of the nutrient level is characterised by hysteresis. The results indicate that manipulation of fish densities as a measure to improve water quality is only likely to produce long-term results when the nutrient level is below a certain threshold.
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  • 48
    ISSN: 1573-5036
    Keywords: growth ; nutrition ; peanuts ; phosphorus ; VA mycorrhizae ; zinc
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Peanut plants (cv. Shulamit) were grown in an Oxisol soil in pots in the glasshouse to assess effects of soil sterilization and inoculation with spores of vesicular-arbuscular mycorrhizal fungi (VAMF) on the response to five rates of phosphorus (0 to 240 kg P ha−1) and two rates of zinc (0 and 10 kg Zn ha−1) fertilizers. Both P and Zn nutrition were affected by VAMF activity but the dominant role of VAMF in this soil type was in uptake of P. In the absence of VAMF there was a clear threshold level of P application (60 kg P ha−1) below which plants grew poorly, which resulted in a sigmoidal response of dry matter to applied P. The maximum response was not fully defined because dry matter production continued to increase up to 240 kg P ha−1. Tissue P concentration of non-mycorrhizal plants increased linearly with P rate and was always significantly less than that in mycorrhizal plants. Mycorrhizal plants responded without threshold to increasing P rate, attaining maximum dry matter at 120 kg P ha−1 in inoculated sterilized soil and at 30 kg P ha−1 in nonsterile soil. These differences in maximal P rates and in the greater dry matter produced in sterile soil at high P rates were attributed to the negative effects of the root-knot nematodeMeloidogyne hapla in nonsterile soil. Plant weight did not respond to zinc fertilizer but tissue Zn concentration increased with applied Zn. Tissue Zn concentration and uptake were increased by VAMF.
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  • 49
    ISSN: 1573-5060
    Keywords: Solanum sp. ; Solanum tuberosum ; potato ; biomass production ; growth ; frost tolerance ; genetic variation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Plants grown from seed derived by crossing conventional European S. tuberosum material were compared with plants grown from seed derived by crossing S. tuberosum with various, Andean frost resistant tuberbearing Solanum species. Biomass growth at optimal (20°/10°) and suboptimal (10°/4°) temperatures was studied. Differences in increase of fresh and dry matter were found between populations of Andean and European orgins at 10°/4°. At 20°/10° no such differences were found. At suboptimal temperature, Andean hybrids produced significantly more fresh and dry matter than European crosses in two harvests (64 and 178 days old plants). Statistically, Andean hybrids were found to produce the same amount of dry matter per day at both temperatures, over the complete growth period. Height increase and flower development were strongly depressed in European crosses under the suboptimal temperatures, but much less so in Andean crosses. The Andean material appears to be an under utilized resource in potato breeding for cool climates.
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  • 50
    ISSN: 1573-5060
    Keywords: Vigna radiata ; mungbean ; stability ; genotype-environment interaction ; wide adaptability ; AVRDC ; segmented regression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Yield data from the 5th–12th international mungbean nursery (IMN) trials conducted at 23 sites in 15 countries were analyzed by conventional stability analysis—regression of genotype mean on the environmental index, and by segmented regression analysis—fitting separate linear regressions in low yielding and high yielding environments. The gene pool base concept allows comparison of genotypes from different IMN trials grown in different years and sites. A very high positive linear relationship was observed between the regression coefficient and the average yield of cultivars, indicating that high yielding cultivars were less stable across environments. When data points of the regression of genotype mean and site mean for VC 1973A, a high yielding and widely adapted cultivar, were examined, the relationship appeared not to be linear. The segmented regression analysis improved the coefficient of determination (r2) and the genotypes were grouped based on regression coefficients in high yielding and low yielding environments. Different categories of genotypes suitable for high input environments, widely adaptable genotypes, and highly stable genotypes were identified.
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  • 51
    ISSN: 1573-5087
    Keywords: Mixtalol ; long chain alcohols ; Indian mustard ; Brassica juncea ; growth ; yield
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Mixtalol (a mixture of long chain aliphatic alcohols varying in chain length from C24 to C32) applied to Brassica juncea plants as foliar spray caused an increase in secondary and tertiary branching with consequent enhancement in seed yield through increased number of inflorescences and siliquae per plant. The percentage of immature siliquae and shattering of siliquae decreased with this treatment. Mixtalol increased total dry matter of plants, partitioning coefficient and harvest index. The contents of starch, protein and oil were also higher in seeds from Mixtalol treated plants.
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  • 52
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    Hydrobiologia 178 (1989), S. 193-198 
    ISSN: 1573-5117
    Keywords: diet ; growth ; flounder
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Many O-group flounder, Platichthys flesus, live in the lower reaches of rivers in North West Europe; while there is extensive information on the niche that they occupy in estuarine and marine environments, little is known of their life in freshwater. The diet of O-group flounder in the Lower Welsh River Dee was studied by stomach contents analysis of diel and seasonal samples. The dominant prey were chironomid larvae and pupae, tubificid oligochaetes and cyclopoid copepods. There was little quantitative variation in diet temporally, although a weak crepuscular pattern of stomach fullness was shown. There was wide variation in length and weight in all months, but the mean values at age I were 60 mm and 2.9 g respectively.
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  • 53
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    Hydrobiologia 188-189 (1989), S. 123-135 
    ISSN: 1573-5117
    Keywords: ecosystem stress ; fish populations ; growth ; fecundity ; condition factor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The status of a fish population is a reflection of the overall condition of the aquatic environment in which that population resides. As such, fish population characteristics can be used as indicators of environmental health. Simple and inexpensive methods to follow fish population responses to environmental degradation are lacking. This paper outlines a protocol whereby environmental impacts on fish populations are classified by five patterns based on characteristics such as mean age, fecundity and condition factor. The patterns summarize population changes and describe responses to exploitation, recruitment failure, the presence of multiple stressors, food limitation and niche shifts. Classification is best based on the selection, and appropriate sampling, of a comparable reference population. Population characteristics can be used to examine ecosystems exposed to stressors for evidence of long-term damage, and when used with biochemical indicators, can be a powerful tool for ecosystem health assessment. The five responses are illustrated using published data on a number of species challenged by increased predation pressure, acidification, eutrophication, mine waste and reservoir impoundment. Application of this scheme will aid in directing and focusing research efforts on crucial aspects impacted by changing conditions.
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  • 54
    ISSN: 1573-5117
    Keywords: Plecoptera ; Isoperla ; life cycles ; growth ; competition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Studies on the life cycle and growth ofIsoperia grammatica andI. difformis from eight southern Swedish streams demonstrated that the former species shows greater between-stream differences than the latter species.I. grammatica larvae had typically two periods of rapid growth, autumn and spring, whileI. difformis larvae grew mainly in autumn-winter. In one of the streams, however,I grammatica grew rapidly throughout all winter. Maximum larval size differed between streams, and so did the timing of the first appearance of nymphs and nymphal maturation. Temperature was probably the most influential factor explaining all these differences. While sexual dimorphism inI. grammatica is slight but significant, it is very prominent inI. difformis. The sizes of larvae overlapped little between species as well as sexes suggesting that intra- and interspecific competition was, or had been, important. InI. grammatica this reduced overlap was expressed in several size-classes of males and females successively replacing each other, resulting in a meandering pattern of the size distribution charts. There were additional indications of possible interactions, such as a significant negative correlation between the densities of the two species.
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  • 55
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    Hydrobiologia 171 (1989), S. 159-170 
    ISSN: 1573-5117
    Keywords: Daphnia galeata mendotae ; Daphnidae ; Cladocera ; Crustacea ; cyclomorphosis ; phenotypic variability ; stability ; temperate lake ; coefficient of variation ; invertebrate predation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phenotypic change is studied in a cyclomorphicDaphnia galeata mendotae population known from previous studies to be clonally diverse. Morphological analyses revealed cyclical changes in both adult and juvenile helmet length and tailspine length which were: 1) strongly correlated with mean water temperature; and 2) repeated annually during the 3-year study period. Field populations exhibited high (5% to 30%) coefficients of variation (CV) for both helmet length and tailspine length; the CV also exhibited seasonal fluctuations such that it was lowest in late summer. The period of highestDaphnia helmet development coincides with peak densities of the common invertebrate predatorsChaoborus andLeptodora. The fluctuations in CV may be due to both differential phenotypic expression of the coexisting clones and invertebrate predation.
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  • 56
    ISSN: 1573-5117
    Keywords: thermal structure ; heat content ; stability ; annual cycle ; diel variation ; tropical lakes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The thermal structure, heat content and stability were studied in Lakes Dom Helvécio and Carioca during an annual cycle. It was found that the maximum heat content, stability and work of the wind in Lake Dom Helvécio correspond to two, four and four times, respectively, the values for the Lake Carioca. These difference can be attributed to morphometric differences in the lakes. A long-term record of heat content and stability for lake Carioca is also presented. Diel variations were studied in summer and winter. The tropicality of the lakes is discussed and compared with other lacustrine systems.
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  • 57
    ISSN: 1573-5117
    Keywords: effects ; heavy metals (Cu, Zn) ; mayfly ; growth ; emergence ; indoor artificial streams
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Effects of Cu and Zn through food as well as through the water on the growth and emergence of the young larvae of Epeorus latifolium (Ephemeroptera), were investigated using an indoor model stream. The critical lowest concentrations of Cu which have significant effects on the growth of the larvae were between 10 and 15 µg l-1 Cu. Growth and emergence of the larvae fed on the algae (diatoms) which accumulated more than 1000 µg Cu g-1 (dry wt.) were significantly impaired. Growth of the mayfly larvae exposed to 100 or 300 µg l-1 Zn ceased after the second week, and all died before emergence. At 30 µg l-1 Zn, the growth rate decreased gradually and many larvae died before emergence. The molt interval also nearly doubled that of the control at these concentrations. Growth and emergence of the mayfly fed the algae which accumulated more than 2000 µg g-1 of Zn were significantly affected.
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  • 58
    ISSN: 1573-5117
    Keywords: ammonium uptake ; carbon uptake ; chlorophyll a ; growth ; loss ; phytoplankton
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Daily changes of inorganic carbon and nitrogen uptake were measured in May in 1986 in Lake Nakanuma, Japan. Uptake of inorganic carbon and ammonium in the light-bottle experiments in the 1 m layers, showed daily changes similar to chlorophyll a changes, though the uptake activities peaked before chlorophyll a peaks (phytoplankton blooms) appeared. Potential growth rates of phytoplankton and observed growth rates were calculated from the uptake rates and chlorophyll a changes. The potential growth rates did not always correspond to the observed growth rates. The potential growth rates did not correlate with the loss rates. The correlation between the observed growth rates and the loss rates was better. These results suggest that though the increase of uptake activities may be necessary for occurrence of phytoplankton blooms, loss processes may affect the occurrence of blooms.
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  • 59
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    Fish physiology and biochemistry 7 (1989), S. 395-405 
    ISSN: 1573-5168
    Keywords: endocrinology ; fish ; farming ; reproduction ; spawning ; sex control ; growth ; smoltification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
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  • 60
    ISSN: 1573-5036
    Keywords: Alnus incana ; field ; Frankia ; growth ; intact plants ; nitrogenase activity ; nitrogen fixation ; photosynthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The nitrogen-fixing grey alder,Alnus incana (L.) Moench, has a potential use in forest soil restoration and as part of energy forestry plantations. As a first step to estimate nitrogen fixation byA. incana under field conditions we performed studies on nitrogenase activity and its possible relation to abiotic factors and growth of the alders. Nitrogenase activity was measured as acetylene reduction activity (ARA) on eleven 1-year-old seedlings ofA. incana inoculated with a local source ofFrankia and planted in an experimental plot located in Umeå, northern Sweden. Each alder was planted into an open-ended cylinder which was closed with a gas tight lid around the stem base to serve as cuvette during ARA measurements. Propane served as tracer gas. ARA was measured in the middle of the day at 15 occasions during 26 June to 29 September 1987. Growth was recorded as leaf area and top shoot length at each ARA measurement until the end of August. Weather conditions were recorded for the whole growing season. Maximal ARA was recorded in late July or early August and ranged from 1.86 to 106μmol C2H4plant−1h−1. Final leaf area ranged from 0.022 to 0.124 m2. A relationship between ARA and the number of hours of sunshine during the same day was observed. ARA in relation to soil temperature increased during the study period, except for the last measurements. ARA in relation to leaf area was initially high but decreased later on. It is suggested that as leaves got older their contribution to photosynthesis per unit leaf area decreased and their potential to deliver nitrogen for retranslocation within plant increased. Both of these events would cause reduced ARA per unit leaf area. The data on ARA, growth, and abiotic factors taken together supported the view that sunshine and weather conditions affected photosynthesis and thereby delivery of assimilates to the nodules.
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  • 61
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    Plant cell, tissue and organ culture 16 (1989), S. 89-102 
    ISSN: 1573-5044
    Keywords: Daucus carota ; suspension cultures ; 2-deoxy-D-glucose ; invertase ; sugars ; growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Carrot (Daucus carota L.) cell suspension cultures grew well when provided with glucose, fructose, sucrose or raffinose. Galactose and melibiose supported less growth unless supplemented with glucose or fructose. In combination with ten different sugar mixtures, 2-deoxy-D-glucose (dGlc) inhibited culture growth. Inhibitory effects of dGlc were more marked with fructose, melibiose, raffinose or mixtures of these sugars in the culture medium. The presence of glucose or galactose reduced the inhibitory effects of dGlc on culture growth. Experiments with radioactive labelled sugars demonstrated that dGLc uptake was greater in the presence of fructose than glucose, and that growth inhibition of dGlc coincided with its uptake. Reduced protein content was also associated with the inhibitory effects of dGlc. Cultured cells contained lower levels of invertase (EC 3.2.1.26) activity during the active phase of culture growth (up to 25 days after subculture) than when growth had peaked and subsequently declined. Acid and alkaline invertase activities were not greatly reduced by exogenous hexoses. Invertase activity was greatest during periods of low protein content in all cultures and was inhibited by dGlc during the latter phases of the culture period. Free intracellular sugars throughout the culture period consisted mainly of glucose and fructose.
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  • 62
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    Fish physiology and biochemistry 6 (1989), S. 11-18 
    ISSN: 1573-5168
    Keywords: skeleton photoperiod ; smolt ; endogenous rhythm ; growth ; osmoregulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Underyearling coho salmon fry were subjected to three initial photoperiod treatments (6L∶18D, 10L∶14D, 14L∶10D) for two months and subsequently to three final treatments (16L∶8D, 9L∶6D∶1L∶8D, 10L∶14D) in a factorial design. Growth rates and seawater adaptability were monitored regularly. The groups that were exposed initially to 6L∶18D or 10L∶14D and then to 16L∶8D grew faster and had lower plasma sodium ion levels after seawater challenge tests than any of the other groups. Fish which were initially exposed to 6 L or 10 L daylength and then to a 9L∶6D∶1L∶8D skeleton photoperiod, showed a slightly lower growth rate and seawater adaptability than those given the corresponding complete 16L∶8D photoperiod. However fish maintained on skeleton photoperiods had significantly greater growth rates and seawater adaptability than those kept on the 10L∶14D photoperiod. This indicates that it is not the accumulated number of hours of exposure to light that initiates smolting, but rather the time during the day when light is experienced. Fish exposed initially to 14L∶10D showed little or no response to subsequent changes in photoperiod, suggesting that responsiveness to inductive photoperiods depends on the initial photoperiod treatment.
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  • 63
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    Fish physiology and biochemistry 7 (1989), S. 49-58 
    ISSN: 1573-5168
    Keywords: fish ; endocrinology ; reproduction ; hypophysation ; growth ; stress ; behavior ; fish culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the current practice of fish culture the use of hormones is mainly limited to the field of reproduction, and more precisely to induce or synchronize ovulation and stimulate spermiation. The practice of pituitary homogenates injection (called hypophysation) which started in the early 1930's has allowed spectacular developments in the culture of some cyprinid species, especially in China, India and Europe. HCG has been used successfully in a limited number of species and LHRH-A, often associated with antidopaminergic compounds, started to be used in some species, especially cyprinids, on a commercial scale. Sex steroids are now commonly used to reverse the sex of some species in salmonids, cyprinids, tilapias. Due to legal restriction and consumer opposition, the tendency is to limit the use of steroids, especially in fish which are later offered to consumption. GH, which significantly stimulates growth and reduces the food conversion rate in laboratory experiments, will possibly be used on a large scale in fish farms. Endocrinology has considerably increased the knowledge of the mechanisms controlling some physiological functions; this has allowed the identification of sensitive phases in fish in captivity, and helps in the management and the process of domestication (most of the cultured fish species have been taken form the wild recently).
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    Fish physiology and biochemistry 6 (1989), S. 113-120 
    ISSN: 1573-5168
    Keywords: growth ; endocrinology ; reproduction ; triploid ; salmonid ; sterilization ; aquaculture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This paper describes the effect of triploidy on growth and reproductive endocrinology in the months leading up to and including spawning in rainbow trout,Salmo gairdneri, and pink salmon,Oncorhynchus gorbuscha. Growth rates were the same for diploid and triploid rainbow trout, but triploid female pink salmon were smaller than maturing diploid females and diploid and triploid males of the same age. Triploid males of both species developed typical secondary sexual characteristics and had normal endocrine profiles, although their cycle appeared to be delayed by about one month. Triploid females remained silvery in appearance and showed no endocrine signs of maturation, even at the level of the pituitary. Thus, although triploids of both sexes are genetically sterile, only the females do not undergo physiological maturation.
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  • 65
    ISSN: 1573-5168
    Keywords: carp ; anabolic-androgenic steriods ; growth ; tissue RNA/DNA ratios
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A study on the effect of three different anabolic-androgenic steroids on the growth, food conversion efficiency and nucleic acid contents of liver, kidney, brain and muscle of carp,Cyprinus carpio was undertaken. The three steroids, methyltestosterone (MT), ethylestrenol (EE) and oxandrolone (ON), were fed in different combinations at final concentrations of 5 or 6 mg/kg diet for 60 days. No effect on the growth was observed in any of the experimental groups. A decrease in the specific growth rate (11–21%) and food conversion efficiency (20–29%) was noted. Feeding of drugs increased the cranio-somatic and reno-somatic index in all except one group. Hepatosomatic (ON+MT) and viscero-somatic (ON+MT; EE+MT+ON) indices decreased. Protein increased and RNA/DNA decreased in only one group while a decrease in protein/DNA was observed in the liver of all experimental groups. RNA/DNA increased and protein/RNA decreased only in one group while no effect was seen in protein and protein/DNA contents in any of the treated kidneys. Proteins, protein/RNA and protein/DNA decreased in certain groups in brain tissue. In muscle, no effect was seen in proteins or protein/DNA. Protein/RNA decreased in all but one group while RNA/DNA was higher only in the group fed all the three steroids together.
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  • 66
    ISSN: 1573-1561
    Keywords: European corn borer ; Ostrinia nubilalis ; Lepidoptera ; Pyralidae ; corn ; DIMBOA ; 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one ; tritiated DIMBOA ; toxicokinetics ; topical application ; body burden ; growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract 2,4-Dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA), the major hydroxamic acid present in corn, and its tritiated derivative, were prepared synthetically for use in the determination of the toxicokinetics of this insect deterrent in the European corn borer (ECB),Ostrinia nubilalis. In growth studies with DIMBOA (0, 0.05, 0.2, and 0.5 mg/g diet), the mean time to pupation and adult emergence were significantly lengthened by an increase in concentration. Pupal and adult weights, for both female and male, decreased with an increase in concentration. Increased larval and pupal mortality occurred at the highest concentration of DIMBOA. DIMBOA, at concentrations of 0.2 and 0.5 mg/g diet, resulted in a decrease in the number of egg masses produced per female, and at 0.5 mg/g diet, in a decrease in the number of eggs per egg mass. Larvae fed from the neonate stage on a diet containing 0.2 mg [3H]- + [1H]DIMBOA/g diet showed an increase in the content of label from fourth to fifth instar, but levels declined at pupation and emergence. A large amount of the labeled compounds was excreted by the insect in the pupal case. In dose-related studies, both uptake and excretion increased with an increase in concentration of DIMBOA (0.05, 0.2, 0.4 mg/g diet), while a body burden (concentration in the tissues/concentration in the frass) of approximately 0.25 was maintained for all concentrations. At the highest dose of DIMBOA (0.4 mg/g), the ECB increased consumption, possibly to compensate for the toxic effects of the compound. In topical application studies, elimination of the labeled compound in the frass was rapid, reaching 65% by 4 hr and 88% by 48 hr. Accumulation of label in tissues other than hemolymph was low. The results show that the ECB does possess adaptive mechanisms to deal with the effects of this host-derived compound.
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    Rheologica acta 28 (1989), S. 504-510 
    ISSN: 1435-1528
    Keywords: Taylor-Couette flow ; stability ; Doi-Edwards equation ; inertia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Abstract The stability of Taylor-Couette flow of entangled polymeric solutions to small axisymmetric stationary disturbances is analyzed using the Doi-Edwards constitutive equation in the small gap limit. A previous analysis of Karlsson, Sokolov, and Tanner for the general K-BKZ equation, of which the Doi-Edwards equation is a special case, reduces the problem to one of numerically evaluating seven viscoelastic functions of the shear rate $$\dot \gamma$$ in the gap. Of these seven, only three — two of which are related to the second normal stress difference, and one of them to shear thinning — significantly affect the flow stability. The negative second normal stress difference of the Doi-Edwards fluid stabilizes the flow at low values of the Weissenberg number λ1 $$\dot \gamma$$ , while shear thinning produces strong destabilization at moderate Weissenberg number. Hereλ 1 is the longest relaxation time. Non-monotonic effects of viscoelasticity on Taylor-Couette stability analogous to those predicted here have been observed in experiments of Giesekus. The extreme shear thinning of the Doi-Edwards fluid is also predicted to produce a large growth in the height of the Taylor cells, a phenomenon that has been seen experimentally by Beavers and Joseph.
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  • 68
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    Rheologica acta 28 (1989), S. 499-503 
    ISSN: 1435-1528
    Keywords: Taylor-Couetteflow ; stability ; Boger fluid ; Oldroyd-B equation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Abstract Experimental evidence of a non-inertial, cellular instability in the Taylor-Couette flow of a viscoelastic fluid is presented. A linear stability analysis for an Oldroyd-B fluid, which is successful in describing many features of the experimental fluid, predicts the critical Deborah number,De c , at which the instability is observed. The dependence ofDe c on the value of the dimensionless gap between the cylinders is also determined.
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  • 69
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    Acta applicandae mathematicae 14 (1989), S. 125-133 
    ISSN: 1572-9036
    Keywords: 92A07 ; stationary solution ; immune response ; stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Some results connected with a simple mathematical model of infectious disease are discussed in order to demonstrate the approach to the modelling of such real processes. A more complicated model of antiviral immune response is presented. A new modification of this model in which targets for the viruses are immunocompetent cells is suggested.
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  • 70
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    Acta applicandae mathematicae 15 (1989), S. 211-234 
    ISSN: 1572-9036
    Keywords: 70F99 ; 70K20 ; 73C02 ; 35P30 ; Flexible body ; Lagrangian and Hamiltonian dynamics ; stability ; partial differential equations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We analyse here the equations of motion of a planar body consisting of a rigid body with attached flexible rod. These equations take the form of coupled ordinary and partial differential equations. We analyse the equations both with and without centrifugal stiffening effects. Using the ‘energy-momentum’ method, we analyse nonlinear stability of the equilibria in each case. We also analyse the Hamiltonian and Poisson bracket structure of the system as well as the energy-momentum map and associated relative equilibria.
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  • 71
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    Journal of statistical physics 56 (1989), S. 533-545 
    ISSN: 1572-9613
    Keywords: Immune system ; dormant B cells ; cycles ; Jerne theory ; memory ; nonlinear phenomena ; stability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The role of dormant B cells and cycles is analyzed in the context of a Lotka-Volterra network. It is shown that dormant B cells stabilize a cycle and that in this way both cooperate to preserve the internal image (memory) of an antigen. The network is embedded in a hierarchical scheme which allows adaptation, learning, and innovation by biased and random mutation.
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  • 72
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    Pharmaceutical research 6 (1989), S. 971-975 
    ISSN: 1573-904X
    Keywords: lyophilization ; stability ; pH effect ; moexipril
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    Topics: Chemistry and Pharmacology
    Notes: Abstract Because of the limited stability of moexipril (RS-10085; 1) in aqueous solution, lyophilized parenteral formulations were evaluated as a function of pH in this study. In general, the lyophilized powder of 1 showed about two orders of magnitude less reactivity at 50°C than in aqueous solution at pH values below 3 or above 6. At pH 5.1, however, the lyophilized powder had maximum reactivity, with the rate actually comparable to that observed in aqueous solution. When the distribution of the two major products, diketopiperazine (DKP) 2 and ester hydrolysis analogue 3, was compared to the observed kinetics as a function of pH, it was clear that removal of water via lyophilization suppressed the spontaneous k 1 cyclization process, the spontaneous k 3 hydrolysis process, and the specific base-catalyzed k 4 hydrolysis process. The overall spontaneous k 2 cyclization process, however, was not affected by lyophilization. The latter result is accounted for by the increased equilibrium constant for the formation of the tetrahedral intermediate, To, as a result of lyophilization. This study demonstrates that stability data in solution can not be used for predicting the stability of moexipril in lyophilized powder form.
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  • 73
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    Journal of optimization theory and applications 63 (1989), S. 79-89 
    ISSN: 1573-2878
    Keywords: Probabilistic constrained programs ; feasible solution sets ; stability ; point-to-set maps
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In this paper, we show the continuity of the feasibility set with respect to the reliability levels and with respect to the distribution of the random elements of a stochastic program with probabilistic constraints. Continuity is then used to obtain stability results for this type of stochastic program. An easy criterion is given for checking the conditions which guarantee the continuity of the feasibility set.
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  • 74
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    Journal of optimization theory and applications 61 (1989), S. 73-94 
    ISSN: 1573-2878
    Keywords: Decentralized control ; stabilization by output feedback ; stability ; numerical methods ; discrete-time linear systems
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    Topics: Mathematics
    Notes: Abstract In this paper, we present an approach for designing structural constrained controllers for discrete-time linear systems, based on a new stabilizability property of the Riccati equation solution. First, the feedback stabilization problem under a general structural constraint is considered and a simple numerical procedure to solve it is presented. Special attention is given to the output feedback stabilization problem, for which sufficient conditions for the existence and convergence toward a stabilizing matrix are provided. Some examples are solved and comparisons with other methods available in the literature are made.
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  • 75
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    Journal of optimization theory and applications 61 (1989), S. 403-408 
    ISSN: 1573-2878
    Keywords: Isoperimetric inequalities ; stability ; circular rings ; structural optimization
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    Topics: Mathematics
    Notes: Abstract The problem of determining the optimal cross section of a circular ring so as to maximize the buckling pressure under a given total volume is formulated and solved. An isoperimetric inequality is proved: Among all the circular rings of given mass and radius, the ring with constant bending rigidity along the arc length has the largest critical buckling pressure.
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  • 76
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    Journal of optimization theory and applications 62 (1989), S. 419-447 
    ISSN: 1573-2878
    Keywords: Minimax optimization ; parametric optimization ; transversality ; sensitivity ; stability ; Chebyshev approximation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We consider functions of maximum type (max functions for short), subject to (in)equality constraints. The space dimension is finite, and the maximum is taken over a compact manifold with boundary. Effective local minimization algorithms based on Newton's method can be derived in the case where a local minimum is nondegenerate (in a two-level sense). In fact, nondegeneracy refers on the one hand to a local (implicit) reduction of the original max function to another one, where the maximum is taken over a finite set. On the other hand, it refers to strict complementarity and nondegeneracy of the underlying quadratic form with respect to the reduced stationary situation. As the main goal, we show that the set ofn-parameter families of functions, for which the stationary points of the corresponding max function are nondegenerate, constitutes an open and dense subset in the space of alln-parameter families (the topology used takes derivatives up to second order into account). An application to approximation problems of Chebyshev type is presented.
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  • 77
    ISSN: 1435-1536
    Keywords: Emulsions ; stability ; interfacial properties of emulsions ; soybean protein ; glycerides ; stabilised O/W emulsions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The influence of chemically modified 7S fraction of soybean protein (7MSPF), and its partial replacement by mono- and di-glycerides in various ratios, on the rate of drop coalescence in concentrated corn oil-in-water emulsions has been investigated. A total emulsifier concentration of 2.0 % (wt/wt) was used. The minimum drop coalescence rate was achieved when using 1.0% (wt/wt) 7MSPF in conjunction with 0.5% (wt/wt) monoglyceride and 0.5 % (wt/wt) di-glyceride at pH 5.5. At other mono-/di-glycerides and protein/glycerides ratios, and at other pHs, the rate of drop coalescence was higher than when 2.0% (wt/wt) 7MSPF was used. The reduction in drop coalescence rate under these conditions is attributed to association of 7MSPF with the glycerides at the oil-water interface. The influence of protein/glycerides ratio on the viscoelastic properties of mixed interfacial films supports this view.
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  • 78
    ISSN: 1570-7458
    Keywords: Homoptera ; Aphididae ; Acyrthosiphon pisum ; Medicago sativa ; resistance ; amino acids ; sucrose ; phloem sap ; artificial diet ; ingestion ; growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumé Sur des milieux holidiques se différenciant par leur concentration en acides aminés ou en saccharose ou par leur spectre en acides aminés et copiant la sève de deux variétés de luzerne (sensible et résistante) nous avons étudié différents paramètres biologiques d'un biotype d'Acyrthosiphon pisum Harris afin de mieux comprendre les mécanismes de résistance à ce puceron. Que ce soit pour le reproduction et la survie des adultes ou pour la croissance et le développment larvaire, nous montrons l'influence spécifique de la concentration en saccharose et en acides aminés ainsi que celle du spectre en acides aminés des régimes artificiels. Ces différences de performances de A. pisum peuvent en partie être expliquées par les différences d'ingestion. Néanmoins pour des rapport saccharose/acides aminés identiques et pour des niveaux d'ingestion égaux, il existe selon les milieux de grandes différences de taux de reproduction et donc d'efficacités métaboliques. Les milieux copiant la sève de variétés sensible et résistante permettent jusqu'à présent d'expliquer une partie des observations faites sur végétal, mais démontrent que l'ignorance de certains facteurs phagostimulants présents dans la plante empêche une interprétation complète des effets observés.
    Notes: Abstract In order to understand the mechanisms of resistance of two lucerne cultivars (susceptible ‘Resistador’ and resistant ‘Lahontan’ clones) to a French biotype of Acyrthosiphon pisum Harris, several biological parameters of this aphid were investigated on sap-copied holidic diets differing either by their amino acid or sucrose concentrations or by the relative proportions of some amino acids. We recorded the quantitative influence of nutrient levels and amino acid profiles on adult survival and reproduction, as well as on larval growth and development. The differences in A. pisum performances on artificial diets may partly by explained by variable ingestion rates, but also by differences in metabolic efficiency of the ingested nutrients, which greatly depends on amino acid composition. Although holidic diet experiments partially confirm the biological assays of resistance on plants, they also point out a lack in our understanding of the factors present in the sap which are involved in phagostimulation in vivo, thus preventing a complete interpretation of observed resistance.
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  • 79
    ISSN: 1570-7458
    Keywords: Coccinellidae ; Harmonia axyridis ; Semiadalia undecimnotata ; Aphids ; Acyrthosiphon pisum ; Pyralidae ; Anagasta kuehniella ; growth ; reproduction ; breeding ; natural prey ; unnatural prey
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Summary Aphidophagous coccinellids Harmonia axyridis and Semiadalia undecimnotata were reared on eggs of the pyralid moth, Anagasta kuehniella during three generations previously killed by exposure to ultra violet radiation. Incidentally, these eggs are used for the mass production of Trichogramma. For H. axyridis larvae, this prey has the same nutritional value as the aphid Acyrthosiphon pisum (control). In adults, it causes an increase in reproductive activity which persisted during three generations. Decreased egg fertility is compensated for by stimulated oviposition. However, regardless of generations, the number of larvae produced per female per day remained equal to or became larger than the control. When the adults are transferred to aphid prey after 15 days of oviposition on the substitution food, a high level of fecundity is maintained and egg fertility improved, particulary during the last two generations. In S. undecimnotata, a specific aphid predator, preying on substitute prey is associated with prolonged pre-imaginal development and increased mortality, the latter affecting up to 50% of the larvae during the third generation. In adults, it induces a deterioration of the reproductive capacities (fecundity, fertility) which however seemed to improve during the third generation. Substitute prey has negative effect on these adults. At present, only H. axyridis might be considered for temporary mass production, as suggested by the results obtained at the end of the first generation.
    Notes: Résumé Les coccinelles aphidiphages Harmonia axyridis Pallas et Semiadalia undecimnotata Schneider (Coccinellidae) ont été élevées pendant trois générations à l'aide d'oeufs d'Anagasta kuehniella Zell. (Pyralidae) tués par une exposition à un rayonnement ultraviolet. Chez la première espèce, cette proie de substitution présente une valuer alimentaire comparable si ce n'est pas supérieure à celle du puceron Acyrthosiphon pisum (Harris). Ces résultats permettent d'envisager, dès à présent, une production massive dans ces conditions trophiques. La mise en place d'un élevage continu dépend de l'évolution sur un grand nombre de générations de certains paramètres biologiques notamment de la fertilité des femelles. Chez la seconde espèce, une telle application paraît impossible pour l'instant.
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  • 80
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    Entomologia experimentalis et applicata 48 (1988), S. 225-232 
    ISSN: 1570-7458
    Keywords: Avena macrostachya ; Hordeum bogdani ; resistance ; Rhopalosiphum padi ; growth ; excretion ; amino acids ; leaf anatomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Résumè Lors d'examens systématiques antérieurs, Avena macrostachya (Bal. ex Coss. & Dur.) et Hordeum bogdani (Wil.) ont présenté une résistance élevée au puceron Rhopalosiphum padi (L.). Lorsqu'ils avaient un choix comprenant de l'avoine et de l'orge cultivés, les pucerons ailés ont atterri en nombres moins importants sur les espèces sauvages. Les résultats étaient cependant variables dans le complexe avoine. La production de nymphes et le poids des adultes étaient plus élevés sur espèces cultivées, ainsi que la durée du développement était plus longue sur les espèces sauvages. A partir du troisième stade, l'excrétion de miellat a été significativement plus faible sur les espèces résistantes. En général, le miellat y contenait moins de 1% d'acides aminés bien que sur H. vulgare il en contînt 3,5%. Les pourcentages d'acides aminés libres du miellat étaient semblables sur toutes les plantes (5,2–7,6%), à l'exception de H. vulgare sur lequel les pucerons excrétaient 22% des taux ingérés. Les acides aminés excrétés en fortes quantités sur les différentes plantes, comprenaient l'asparagine, l'acide γ-aminobutyrique, l'acide glutamique et la glycine. Des coupes de tissus n'ont révélé aucun obstacle mécanique clair à la pénétration des stylets. Les possibilités d'utiliser ces espèces sauvages comme source de résistance aux pucerons dans la sélection de l'avoine et de l'orge ont été examinées.
    Notes: Abstract In previous screening tests the two wild crop relatives Avena macrostachya (Bal., ex Coss. et Dur.) and Hordeum bogdani (Wil.) demonstrated a high degree of resistance to the aphid Rhopalosiphum padi (L.). In a choice situation using wild and cultivated oats and barley, alate aphids settled in lower numbers on the wild species. The results were, however, variable in the Avena combination. Nymph production was significantly higher, development time shorter and adult weight higher on the cultivated varieties. From the third instar and onwards the excretion of honeydew was significantly lower on the resistant plants. In general the honeydew contained less than 1% free amino acids although excreta from H. vulgare contained 3.5%. The percentage of free amino acids found in the honeydew was similar for all plant species (5.2–7.6%) except for H. vulgare, on which the aphids excreted 22% of the amounts ingested. Amino acids excreted in high proportions on all plants included asparagine, γ-aminobutyric acid, glutamic acid, and glycine. Tissue sectioning did not reveal any obvious mechanical barriers to stylet penetration. The potential use of these wild species as sources for aphid resistance breeding in oats and barley is considered.
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    K-Theory 2 (1988), S. 1-355 
    ISSN: 1573-0514
    Keywords: Pseudoisotopy ; stability ; Morse theory
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract The stability theorem states that the suspension map C(M) → C(M X I) defined on the pseudoisotopy space C(M)=Diff(M X I rel M X O U ∂M X I) of a compact smooth n-manifold M is ∼ n/3-connected. This implies that C(M) has the R~ n/3-homotopy type of the stable pseudoisotopy space P(M) which is related to Waldhausen's algebraic K-theory of spaces by Waldhausen's formula A(X) Ω∞S∞(X+) X B2P(X). This paper gives a detailed proof of the smooth stability theorem following ideas by Hatcher for the proof of a PL stability theorem.
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  • 82
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    Nutrient cycling in agroecosystems 16 (1988), S. 217-226 
    ISSN: 1573-0867
    Keywords: Potassium fertilization ; grain sorghum ; savanna soil ; yield ; growth ; varietal difference ; Nigeria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Field trials were conducted at Samaru over a three-year period (1980–82) to study the yield, growth and nutrient concentration of three grain sorghum varieties (L. 187, SK5912 and FFBL) in relation to potassium fertilization in a savanna soil. Potassium application rates were 0, 25, 50 and 75 kg K ha−1. Year × potassium interactions were not significant although there were significant variety × K interactions. The highest grain yields for var. L.187, SK5912 and FFBL occurred from the application of 25, 50 and 75 kg K ha−1 respectively. Straw yield was generally increased by K application, which also promoted tillering and hastened flowering in grain sorghum. Although grain weight per head, head number per m2, grain number and 1000-grain weight were unaffected by this nutrient, weight per head was reduced by 22.8 per cent. K application enhanced N concentration of sorghum plants but caused decline in P concentration. The highest K rate gave the highest K concentration in each of the three varieties at 7 weeks after planting. Optimum K requirement of grain sorghum would seem to be between 25 and 50 kg K ha−1.
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  • 83
    ISSN: 1573-0867
    Keywords: Zea mays L. ; nitrogen fertilization ; plant density ; yield components ; growth ; micronutrient nutrition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Growth and yield components in field-grown maize (Zea mays L.) were enhanced by nitrogen fertilization ranging from 50 to 200 kg N ha−1. Ear diameter, kernel depth, grain: stover ratio, number of ears plant−1, plant height and dry matter production increased as N fertilization rate was increased up to 100 or 150 kg N ha−1. Tasselling in maize was hastened by N fertilization. Increasing plant density from 25000 to 75000 plants ha−1 increased plant height, dry matter production and delayed tasseling but reduced ear diameter, kernel depth, grain: stover ratio and number of ears plant−1. Increased N supply and plant density had no influence on the concentrations of Mn, Zn, Cu, and Fe in ear leaf; except that Mn concentration increased as N fertilization rate was increased up to 150 kg N ha−1. Nitrogen × plant density interactions on the concentrations of the micronutrients in maize ear leaf were not significant.
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  • 84
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    Cellular and molecular life sciences 44 (1988), S. 776-777 
    ISSN: 1420-9071
    Keywords: Fourier analysis ; growth ; selection ; size ; shape
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Fourier analysis of videodigitised outlines of mouse vertebrae from two stocks, a pseudo-longitudinal series of mice aged 25–60 days and one selected for large or small body size over many generations shows that the shape changes due to normal growth are not similar to those produced by selection for body size.
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  • 85
    ISSN: 1573-3297
    Keywords: genes ; environment ; development ; growth ; twins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Models of developmental continuity and change in quantitative phenotypes may be tested using longitudinal data from twins. We illustrate a procedure for establishing the power and required sample sizes for detecting developmental transmission against an alternative common-factor hypothesis. We explore the general effects of different heritabilities, different fidelities of environmental and genetic developmental transmission, and varying numbers of occasions of measurement. In addition, a constraint of wide application is postulated for the action of the environment; either environmental effects are transmitted (learned) and occasion specific or they exert a constant influence which is not transmitted (learned). While the situations we examine are necessarily restricted here, our explorations of power show that, providing that we measure on at least four occasions, it is easy to detect developmental transmission with workable sample sizes.
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  • 86
    ISSN: 1573-3297
    Keywords: anorexia ; maturity ; feed intake ; growth ; chickens
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Long-term selection for low juvenile body weight has resulted in a line of chickens where sexual maturity is retarded or prevented because of anorexia.Ad libitum-fed pullets which had not commenced egg production by 240 days of age were randomly assigned to be force-fed or fedad libitum. Increasing food intake via force-feeding caused a significantly greater proportion of females to commence egg production than was noted forad libitum-fed controls. Moreover, of those pullets that commenced lay, age at onset was significantly earlier in those force-fed than in those fedad libitum.
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  • 87
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Hypothalamo-neurohypophyseal system ; Vasopressin ; Oxytocin ; Immunohistochemistry ; Phodopus sungorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The topography of oxytocin (OT)- and vasopressin (VP)-containing axons of the hypothalamo-neurohypophyseal system was studied in the neurohypophysis of the Djungarian hamster (Phodopus sungorus) by means of immunohistochemistry. Compared with other mammalian species, the neurohypophysis of Phodopus shows some peculiarities. Accumulations of OT-immunoreactivity around the distal vessels of the primary portal plexus can be observed in the distal median eminence and neural stem. This staining pattern indicates that OT is secreted into portal blood. In the neural lobe, OT- and VP-immunopositive fibers terminate in different areas. The vast majority of the OT-containing axons is distributed in the dorsal part of the neural lobe. In contrast, VP-containing axons are mainly found in the centre of the neural lobe up to the pars intermedia.
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  • 88
    ISSN: 1432-0878
    Keywords: Immunohistochemistry ; Light microscopy ; Neuroendocrine regulation ; Neuropeptides ; Columba livia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of VIP- and TRH-immunoreactivity in neurons and processes within the hypothalamus of the pigeon was investigated with light-microscopic immunocytochemical techniques. Most of the VIP-containing neurons are concentrated in the middle and caudal parts of the hypothalamus, with the greatest concentration of perikarya occurring in the medial and lateral part of the ventromedial hypothalamic nucleus and the infundibular nucleus. These cells give rise to axons that seem to extend into the median eminence. An extensive network of VIP-immunoreactive fibers and varicosities occupy the external layer of the median eminence. The majority of TRH-containing neurons is found in the anterior hypothalamus with the greatest concentration of cells in the magnocellular preoptic, medial preoptic, suprachiasmatic and paraventricular nuclei. TRH-immunoreactive fibers and varicosities form a dense arborization in the external layer of the median eminence. Lactation seems to induce substantial changes in VIP as well as in TRH-immunostaining in the median eminence and other hypothalamic regions as compared to control, sexually active animals. Furthermore, TRH-immunoreactivity decreased in the median eminence following 60-min exposure to cold. These results suggest that VIP- and TRH-containing pathways in the pigeon hypothalamus are involved in the mediation of neuroendocrine responses.
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    Cell & tissue research 252 (1988), S. 99-106 
    ISSN: 1432-0878
    Keywords: γ-Aminobutyric acid (GABA) ; Glutamic acid decarboxylase ; Immunohistochemistry ; Auditory system ; Chicken (White Leghorn)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of presumed GABAergic neurons and axon terminals in nuclei of the higher auditory pathway of the chicken was investigated by immunocytochemical methods employing antisera to the rate-limiting enzyme of GABA synthesis, glutamic acid decarboxylase, and to GABA. In the mesencephalic auditory center (MLD) about 20% of the cells reveal immunoreactivity. In contrast, the thalamic relay station nucleus ovoidalis is devoid of immunostained somata. This nucleus contains a high density of punctate immunoreactive structures presumed to be GABAergic axon terminals. In the auditory forebrain center field L and the auditory portions of the hyperstriatum ventrale, up to 8% of the cells were immunopositive. These neurons were significantly smaller than estimated from measurements of the overall cell population in these nuclei. From the two-dimensional arrangement of immunopositive neurons it is suggested that the GABAergic system in the avian auditory telencephalon consists of two separate groups of neurons: one subgroup mediating local inhibitory interactions, the other responsible for lateral inhibition between different frequency representations.
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  • 90
    ISSN: 1432-0878
    Keywords: Neuronal markers ; Neuropeptides ; Immunohistochemistry ; Heart innervation ; Atrial natriuretic peptide (ANP) ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innervation and myocardial cells of the human atrial appendage were investigated by means of immunocytochemical and ultrastructural techniques using both tissue sections and whole mount preparations. A dense innervation of the myocardium, blood vessels and endocardium was revealed with antisera to general neuronal (protein gene product 9.5 and synaptophysin) and Schwann cell markers (S-100). The majority of nerve fibres possessed neuropeptide Y immunoreactivity and were found associated with myocardial cells, around small arteries and arterioles at the adventitial-medial border and forming a plexus in the endocardium. Subpopulations of nerve fibres displayed immunoreactivity for vasoactive intestinal polypeptide, somatostatin, substance P and calcitonin gene-related peptide. In whole-mount preparations of endocardium, substance P and calcitonin gene-related peptide immunoreactivities were found to coexist in the same varicose nerve terminals. Ultrastructural studies revealed the presence of numerous varicose terminals associated with myocardial, vascular smooth muscle and endothelial cells. Neuropeptide Y immunoreactivity was localised to large electron-dense secretory vesicles in nerve terminals which also contained numerous small vesicles. Atrial natriuretic peptide immunoreactivity occurred exclusively in myocardial cells where it was localised to large secretory vesicles. The human atrial appendage comprises a neuroendocrine complex of peptidecontaining nerves and myocardial cells producing ANP.
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  • 91
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    Cell & tissue research 254 (1988), S. 331-340 
    ISSN: 1432-0878
    Keywords: GABA ; Interneurons ; Flight ; Immunohistochemistry ; Locusta migratoria (Insecta)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The transmitter content of identified inhibitory interneurons in the flight system of the locust, Locusta migratoria, has been characterized using antibodies raised against protein-conjugated gamma aminobutyric acid. Identified flight neurons were filled with the fluorescent dye, Lucifer Yellow. Serial sections of dye-filled neurons were incubated with an antibody to gamma aminobutyric acid which was subsequently tagged with a fluorescent marker. Excitatory motoneurons to wing muscles and 13 flight interneurons (3 excitatory, 7 inhibitory, and 3 with unknown synaptic effect) were examined. Neither the moto-neurons nor any of the 3 excitatory interneurons contained immunoreactive material. Six of the 7 inhibitory interneurons did contain immunoreactive material. All the neurons which contained immunoreactive material and whose synaptic effect is known were inhibitory. We conclude that most of the inhibitory flight interneurons which have been described use gamma aminobutyric acid as their transmitter. Interestingly, at least 1 set of interneurons known to be inhibitory does not use gamma aminobutyric acid. We predict that the 2 interneurons which do contain immunoreactive material and whose synaptic effect is not yet known will be found to have inhibitory roles in the operation of the flight circuitry.
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  • 92
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    Cell & tissue research 254 (1988), S. 361-367 
    ISSN: 1432-0878
    Keywords: Entorhinal cortex ; Non-pyramidal neurons ; Interstitial neurons ; Somatostatin ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution of somatostatin-immunoreactive cells and processes throughout the human entorhinal region and subjacent white matter was examined either by the unlabelled antibody-enzyme method or by the avidin-biotin method. The brain slices were obtained at autopsy with a short post-mortem delay. The majority of somatostatin immunoreactive nerve cells was found in the inner principal layer and subjacent white matter. In addition, individually scattered immunoreactive neurons were observed in both the outer principal layer and lamina dissecans. The immunoreactive perikarya varied in shape and ranged in size from 10 to 30 μm. Without exception the neurons could be classified as belonging to the group of non-pyramidal neurons. Each neuron gave rise to a few thick dendrites and a thin axon with a beaded appearance. In the adult human brain, the pattern formed by lipofuscin granules deposited in the nerve cells can be considered characteristic for the type of the neuron. Therefore, immunoreactive perikarya were documented, destained of chromogen and restained to demonstrate lipofuscin pigment and basophilic substance. It became evident from these studies that the previously immunoreactive cells were characterized by a large rounded and eccentrically located nucleus, sparse basophilic substance and, in most cases, a lack of lipofuscin granules. A few of the immunoreactive cells were laden with coarse pigment granules. The findings permit classification of entorhinal somatostatin-immunoreactive neurons as either non-pigmented or pigment-laden non-pyramidal neurons.
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  • 93
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    Cell & tissue research 254 (1988), S. 341-346 
    ISSN: 1432-0878
    Keywords: Odontoblast ; Calbindin ; Immunohistochemistry ; Electron microscopy ; Teeth ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The presence of 28 kDa calbindin in human odontoblasts was studied by use of specific antibodies raised against chick duodenal 28 kDa calbindin, in immunofluorescence, immuno-peroxidase, and electron-microscopic labelling experiments. The calbindin-like protein was detected mainly in the cytoplasm of odontoblast cell bodies, in their processes and occasionally in their nuclei. Correspondingly, at the ultrastructural level, immunoreactive material was associated with the cytosol, microfilaments and cilia. These findings suggest that human odontoblasts express a 28 kDa vitamin D-dependent calcium-binding protein, unlike those of rats and mice in which ameloblasts are the only cells immunoreactive for the protein.
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  • 94
    ISSN: 1432-0878
    Keywords: Photoperiod ; Pituitary gland, Pars tuberalis ; TSH ; Immunohistochemistry ; Phodopus sungorus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Certain secretory cells in the hypophysial pars tuberalis of the Djungarian hamster display marked circannual structural alterations. The present investigation deals with the immunohistochemical properties of this cell group. A distinct TSH-like immunoreactivity was found in secretory cells of this type in the pars tuberalis of animals exposed to long photoperiods, whereas under short photoperiods the TSH-like immunoreactivity was nearly absent. In the pars distalis, the number and distribution of TSH-positive cells did not differ significantly between animals maintained under long and under short photoperiods. LH-and FSH-positive cells could not be detected in the pars tuberalis, but they are clearly present in the pars distalis of both groups of hamsters. Our immunocytochemical results suggest that photoperiodic stimuli influence the secretory activity of TSH-like immunoreactive cells in the pars tuberalis. A connection with the neuroendrocrine-thyroid axis is discussed.
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  • 95
    ISSN: 1432-0878
    Keywords: Pituitary allografts ; Immunohistochemistry ; Hamster ; Mesocricetus auratus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary We used immunohistochemistry to identify cells present in pituitary allografts in the hamster. Hypophyses removed from neonatal hamsters or adenohypophyses removed from adult females were placed beneath renal capsules of hypophysectomized adult females. Serum PRL, LH, and GH concentrations were measured at two, five, and eight weeks after placement of allografts. Allografts were removed after eight weeks and stained for cells containing PRL, LH, FSH, GH, or ACTH. Allografts did not release LH or GH. Those of adult adenohypophyseal tissue released significantly more PRL. The morphology of allografts of neonatal hypophyseal tissue resembled that of the adult adenohypophysis in situ. Lactotrophs, corticotrophs, somatotrophs and LH-cells were observed; very few FSH-cells were present. Allografts of adult adenohypophyseal tissue contained pituitary cells, numerous cavities, often enclosing lymphoid cells, and fibrous tissue. Atypical lactotrophs were the numerically dominant cells in these allografts; all other cells were present. The LH-cells outnumbered FSH-cells. These observations suggest that: (a) development of normal adenohypophyseal morphology can occur in an ectopic position; (b) intracellular hormones are present in cells in an ectopic site; (c) development and retention of intracellular FSH is more dependent on occupation of the normal position of the adenohypophysis than is retention of intracellular LH; and (d) release of PRL occurs from atypical cells in allografts of adult adenohypophyseal tissue.
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  • 96
    ISSN: 1432-0878
    Keywords: Fine structure ; Immunohistochemistry ; Anterior pituitary gland ; Snell dwarf mice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Snell dwarf mice display remarkable retardation of growth after birth and are known to lack prolactin (PRL), thyroid stimulating hormone (TSH) and growth hormone (GH). The aim of this study was to determine the reason for these hormonal deficiencies. We examined the fine structure of the gland and its immunohistochemical staining pattern with respect to antisera raised against PRL, TSH, GH, adrenocorticotrophic hormone (ACTH) and luteinizing hormone (LH). The gland of control mice reacted immunohistochemically against all antisera used, whereas only ACTH-producing cells (ACTH cells) and LH-producing cells (LH cells) were distinguished in the dwarf mice. ACTH cells in dwarf mice varied in cell shape, although they were similar in size to those of controls. The distribution of secretory granules in the cytoplasm varied from cell to cell. LH cells in the dwarf mice showed immature features, having poorly developed rough endoplasmic reticulum and Golgi apparatus. The cells were about half the size of controls, and secretory granules were smaller. In dwarf mice, non-granulated cells were encountered in addition to granulated ACTH and LH cells. Some of them formed small clusters, characteristic cell junctions being found between the cells; they thus appeared to be follicular cells. The above results suggest that hormone deficiency in Snell dwarf mice is a result of a defect in the hormoneproducing cells in the gland.
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  • 97
    ISSN: 1432-0878
    Keywords: Neurokinin A ; Substance P ; Dental pulp ; Immunohistochemistry ; Cat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The distribution and origin of neurokinin A (NKA)-like immunoreactivity were investigated in feline dental pulp by an indirect immunofluorescence method. NKA-containing nerve fibres with varicosities, which entered the dental pulp via apical foramen, were distributed throughout this tissue. Many NKA-containing nerve fibres were localized around blood vessels, but some were observed apart therefrom. At the odontoblastic layer, thin NKA-containing nerve fibres were observed running straight toward the pulp-predentinal border between odontoblasts. After inferior alveolar nerve section, all NKA-containing nerve fibres disappeared in the dental pulp, while the removal of the superior cervial ganglion resulted in no change in the distribution of these fibres. The correlation of NKA-like immunoreactivity and substance P (SP)-like immunoreactivity was also investigated by double-immunofluorescence technique. The distribution of NKA-containing nerve fibres was very similar to that of SP-containing nerve fibres; it appeared that all NKA-containing nerve fibres contained SP.
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  • 98
    ISSN: 1432-0878
    Keywords: Periodontal ligament ; Incisor ; Neurofilament protein ; S-100 protein ; Immunohistochemistry ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Nervous elements in the periodontal ligament and dental pulp of rat incisors were investigated by means of immunohistochemistry for neurofilament protein (NFP) and glia-specific S-100 protein. The periodontal ligament in the incisors was densely innervated by NFP-immunoreactive nerve fibers; the distribution of the nerve fibers and their terminations differed markedly from those in molars. NFP-positive, thick nerve bundles entered the lingual periodontal ligament through slits located in the mid-region of the alveolar socket, and immediately formed numerous Ruffini-like corpuscles. In the labial periodontal ligament, all of the NFP-immunoreactive nerve fibers terminated in free endings. The restricted location of the stretch receptor, Ruffini-like corpuscle, in the lingual periodontal ligament appears to be an essential element, because this region is regularly extended during mastication. The nervous elements were restricted to the alveolar half of the periodontal ligament in every region; they avoided the dental half of the periodontal ligament, which presumably moves continuously with the tooth. Pulpal nerve fibers in incisors also showed a characteristic distribution different from those in molars; individual nerve fibers with beaded structures ran in the center of the pulp toward the incisai edge, and did not form the subodontoblastic nerve plexus of Raschkow. Immunostaining for S-100 protein revealed a distribution pattern of nervous elements similar to that for NFP, suggesting that the nerves supplying the periodontal ligament and dental pulp were mostly covered by a Schwann sheath.
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  • 99
    ISSN: 1432-0878
    Keywords: Skeletal muscle ; Chronic stimulation ; Fiber transformation ; Myosin heavy chain isoforms ; Immunohistochemistry ; Histochemistry ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Chronically stimulated fast-twitch muscles of the rabbit were histochemically and immunohistochemically analyzed in serial cross sections (1) for percentages of fiber types, and (2) for the presence of myosin heavy chain isoforms during fast-to-slow transformation. By four weeks of stimulation the number of type-I fibers had increased more than fourfold, while only about 6% of the original IIB fibers remained. Type-IC and -IIC fibers transiently rose to 20% of the total fiber population. After 16 weeks, the number of type-I fibers had increased to 42%. With prolonged stimulation fewer fibers reacted with antibodies against embryonic and neonatal myosins and more with the antibody against slow myosin. The reaction for embryonic myosin was most often detected in the C fibers (IC, IIC). Immunohistochemical subtypes were observed for each fiber type in the stimulated muscles. The greatest number was seen in type-IIC fibers, which, in addition to their reaction for fast/neonatal and slow myosins, might also react with the antibodies against neonatal/embryonic and embryonic myosins. These findings indicated that the transforming fibers temporarily expressed myosin heavy chain isoforms normally not detectable in adult skeletal muscle. Myotubes reacted strongly with the antibodies against fast/neonatal and embryonic myosins, and some of them also with the antibody against slow myosin. Thus, it appears that under the influence of the low frequency stimulus pattern some of the newly formed myotubes developed into type-I fibers.
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  • 100
    ISSN: 1432-0878
    Keywords: Neuropeptides ; Vascular innervation ; Immunohistochemistry ; Small intestine ; Guinea pig
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The neuropeptide content of nerve fibers associated with submucosal arteries in the small intestine of guinea pigs was studied in whole-mount preparations using immunohistochemical methods. Tissues were obtained from normal animals or animals in which the small intestine had been extrinsically denervated. In normal animals, submucosal arteries are innervated by extrinsic sensory nerve fibers which contain both substance P and calcitonin gene-related peptide, and by sympathetic noradrenergic nerve fibers. In preparations obtained from animals 5–9 days after denervation, nerve fibers which contained substance P without detectable calcitonin gene-related peptide were associated with a few submucosal arteries. Nerve fibers which contained vasoactive intestinal peptide were also associated with some arteries. By 42–48 days after extrinsic denervation, substance P-containing fibers (without calcitonin gene-related peptide) and vasoactive intestinal peptide-containing fibers were associated with nearly every blood vessel. The extrinsic sympathetic nerve fibers did not regenerate during the course of this study. The nerve fibers associated with submucosal arteries in denervated tissues were not sensitive to capsaicin treatment. The alteration in the innervation of submucosal arterioles that follows extrinsic denervation of the gut may reflect either an increase in the neuropeptide content of the fibers, synthesis of a new peptide, or an increase in the number of fibers as a result of axonal sprouting.
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