ALBERT

Notes: SYNOPSIS. Cortical ultrastructure of the scuticociliates Dexiotricha media and Dexiotricha colpidiopsis was investigated. The following elements of the somatic cortex were studied: the cell membrane, alveolar membranes and the epiplasm, kinetodesmal fibers, postciliary and transverse microtubular ribbons, and transverse fibers associated with single and paired kinetosomes; mitochondria and single microtubules located in interkinetal ridges; mature and early extrusion stages of mucocysts: the expulsion vacuole pore and tube, the nephridioplasm and the cytoproct. In the buccal cortex, the paroral kinety-ribbed wall complex, the 3 polykineties, and the cytostome-cytopharynx were investigated.Comparative survey of ciliate ultrastructure indicates 2 principal orientation patterns for kinetodesmal and postciliary fibers, recognition of which leads to reevaluation of the theory of paroral kinety formation and the ideas of homology based on this theory. Ultrastructurally, the scuticociliates are not distinct from tetrahymenines and peniculines; the 3 groups appear to be 1 assemblage.

Notes: SYNOPSIS. In this study the characteristics of the synthesis of DNA and RNA in the nuclei of Loxodes were investigated. Loxodes striatus is a primitive ciliate with 2 pairs of structurally differentiated diploid nuclei, the macro- and micronuclei. The macronuclei are differentiated morphologically into a clearly recognizable central core and an outer zone.To determine DNA and RNA synthesis, individual organisms were analyzed by autoradiography after incubating groups of cells with a 3H-labeled precursor ([3H]thymidine for DNA and [3H]uridine for RNA).The following observations were made: (A) All portions of macro- and micronuclei appeared to contain DNA as judged by the localizations of incorporated [3H]thymidine. (B) The macro- and micronuclei did not synthesize DNA at the same time; moreover, the duration of DNA synthesis in the former was much longer than of the latter nucleus. (C) Replication of DNA in the inner core and outer zone of the macronucleus occurred at separate times with little if any overlap. (D) All of the detectable [3H]uridine incorporation was found in the macronucleus and none in the micronucleus. Within the macro-nucleus the central core was more heavily labeled. (E) The quantitative differences in the label of the different components of the nuclear complex were investigated. (F) Contrary to the previously reported information our results suggest that DNA synthesis can occur in adult macronuclei.The possible explanation of these results is discussed in the context of the nuclear evolution of ciliates and of recent information on nuclear differentiation.

Notes: SYNOPSIS. Eimeria dispersa (turkey strain) and Eimeria gallopavonis sporozoites were inoculated into primary cultures of chicken kidney (CK) and turkey kidney (TK) cells. Eimeria dispersa sporozoites were more infective in either cell type than those of E. gallopavonis: at 4 hr, the percentage of infection was 67-98 for E. dispersa but only 23-56 for E. gallopavonis. E. dispersa also survived better in culture: at 2 days, losses of E. dispersa in both cell types were only 4-19%, whereas losses of E. gallopavonis were 35-47% in TK cells and 60–95% in CK cells. However, E. gallopavonis developed further than E. dispersa. Location and increase in numbers of intracellular stages at 4 days indicated that E. dispersa proceeded through 2 schizogonic generations before development stopped.

Notes: Book reviewed in this article:Cuatrecasas, P. & Greaves, M. F., eds. 1976, Receptors and Recognition, Vol. I, Series A.

Notes: SYNOPSIS. A mating type analysis was performed on 231 isolates of the cellular slime mold, Polysphondylium pallidum found in 61 samples collected in eastern North America between northern Florida and southern Canada. Seventy-eight percent of the isolates belonged to one of 2 mating types; 18% were incapable of mating with any partner; 3% were homothallic; and 1%, consisting of 2 isolates from a Florida sample, belonged to a separate breeding group. It is suggested that the majority of isolates represent a species capable of local genetic adaptation to a niche, the parameters of which undergo considerable variation over space and time.

Notes: Book reviewed in this article:Avakyan, A. A. 1976. Atlas Anatomii Prosteishikh, Patogen-nykh dlya Cheloveka i Zhivotnykh.

Notes: SYNOPSIS. The ultrastructure of interphase and mitotic nuclei of the epimastigote form of Trypanosoma cyclops Weinman is described. In the interphase nucleus the nucleolus is located centrally while at the periphery of the nucleus condensed chromatin is in contact with the nuclear envelope. The nucleolus fragments at the onset of mitosis, but granular material of presumptive nucleolar origin is often recognizable in the mitotic nucleus. Peripheral chromatin is in contact with the nuclear envelope throughout mitosis, and it seems reasonable to assume that the nuclear envelope is involved in its segregation to the daughter nuclei. Spindle microtubules extend between the poles of the dividing nucleus and terminate close to the nuclear envelope. The basal body and kinetoplast divide before the onset of mitosis and do not appear to have any morphologic involvement in that process. Spindle pole bodies, kinetochores, and chromosomal microtubules have not been observed.

Notes: SYNOPSIS. Developing 2nd- and 3rd-generation schizonts of Eimeria tenella were found in the ceca of chicks infected orally with sporulated oocysts. Several free 2nd-generation schizonts, which varied in diameter from 11 to 21.6 μm, were found on the epithelial surface of the cecum. Some schizonts appeared to have lost merozoites. Other schizonts were intact, one of which was surrounded by an unbroken membrane that followed the contours of the merozoites. Third-generation schizonts, much smaller than 2nd-generation schizonts and with fewer merozoites, were found only on cut or fractured surfaces of the cecal tissue. Third-generation merozoites appeared shorter and thicker than those of the 2nd-generation and were attached to the schizont residuum. A form with conical protuberances and another with 4 triangular segments were found; they were believed to be developing stages 3rd-generation schizonts.

Notes: SYNOPSIS. Cell size, macromolecular composition, carbohydrate utilization patterns, and O2 concentrations were measured throughout the growth stages of Naegleria gruberi in agitated cultures in a complex medium. Biphasic logarithmic growth occurred during the initial 83 hr of growth and the mean generation time was 7.0 hr and 19 hr during initial and secondary log growth stages, respectively. The maximum yield was 5 × 10* amebaeJml. The pH rose rapidly (1 pH unit) during the secondary log growth phase (52-83 hr) and continued into the stationary growth phase (83-120 hr). Dry weight, total protein, carbohydrate, and RNA per ameba increased just before the secondary log growth phase. RNA increased 31% to 35% per ameba at the end of each phase of log growth. DNA increased ∼ 2-fold throughout the different growth phases. Average cell size increased 90% during biphasic log growth then decreased during stationary phase. O2 tension decreased from 100% to 18% of saturation during the biphasic growth phase, then increased during stationary growth to near 100% saturation. Glucose and total carbohydrate assays showed little utilization of those substrates throughout the growth stages. Naegleria gruberi presumably has a predominantly aerobic metabolism, also its metabolism may change during the different growth phases.

Notes: SYNOPSIS. Epizootic outbreaks of red-sore disease in several reservoirs in the southeastern United States have been reported to cause heavy mortality among several species of fish having sport and commercial value. The etiologic agent is said to be the peritrich ciliate Epistylis sp.; secondary infection by the gram-negative bacterium Aeromonas hydrophila produces hemorrhagic septicemia which results in death. However, in recent studies on the largemouth bass Micropterus salmoides, Epistylis sp. could be isolated from only 35% of 114 lesions from 114 fish, while A. hydrophila was found in 96% of the same lesions. Transmission and scanning electron microscopy of lesions associated with red-sore disease indicate that neither the stalk nor the attachment structure of Epistylis sp. have organelles capable of producing lytic enzymes. Since other investigators have shown that A. hydrophila produces strong lytic toxins, and in absence of evidence to the contrary, it is concluded that Epistylis sp. is a benign ectocommensal and that A. hydrophila is the primary etiologic agent of red-sore disease.

Notes: Weiser, Jaroslav. 1977. An Atlas of Insect Diseases, 2nd ed. Dr. W. Junk, B. V., Publishers, P. O. Box 3713, The Hague, Holland and Academia Publishing House, Czechoslovak Academy of Sciences, Prague, Czechoslovakia. 81 + 240 pp. 75 Dutch Guilders.

Notes: SYNOPSIS. The structure and cytochemistry of spores of Myxobolus sp. from plasmodia which occur in the gill filaments of the common shiner Notropis cornutus were studied by light microscopy and by scanning and transmission electron microscopy. The thin-walled valves of the pyriform spores are thickened in the lateral sutural and apical regions. Mucous material is associated predominantly with the posterior end of many spores. The plasmodium is surrounded by a syncytial wall bounded by 2 membranes. Pinocytotic channels are formed by the inner membrane and numerous dense vesicles are pinched off at the distal ends of the channels. Sporogenesis is initiated by the envelopment of one vegetative cell by another. The larger, enveloped cell divides to form a disporous pansporoblast, which contains 2 pairs of capsulogenic and valvogenic cells and 2 binucleate sporoplasm cells. Each capsular primordium and connecting external tubule gives rise to a polar capsule which houses a helically coiled polar tubule. The apical end of each polar capsule is plugged by a stopper. The valvogenic cells surround the capsulogenic and posteriorly situated sporoplasm cells to form the spore valves. Iodinophilic (glycogen) inclusions were not seen in spores stained with iodine or Best's carmine. A darkly stained band was observed around the posterior region of most spores stained with Best's carmine. In the electron microscope large aggregates of β glycogen particles were seen in the cytoplasm of sporoplasm cells in mature spores.

Notes: SYNOPSIS. Eighteen strains of algae, including 17 exsymbiotic from Paramecium bursaria, were tested for infectivity for P. bursaria, syngen 2 aposymbiotes, and Concanavalin A (Con A) agglutinability. All 6 infective algal strains were relatively resistant to agglutination by Con A, suggesting that algal surface characteristics are correlated with infectivity. Among the noninfective strains, high and low agglutinability were about equally represented, indicating that the Con A titer alone is not a sufficient indicator of infectivity. It is suggested that noninfective algal strains are the progeny of mutations occurring within the endozoic population and fortuitously selected by the external culture medium.

Notes: SYNOPSIS. Studies on sexual compatibility among populations of different origins of axenically cultivated, heterotrophic, homothallic dinoflagellates resembling Crypthecodinium cohnii have been undertaken using motility mutants and complementation testing. We showed previously that one interbreeding group or biologic species can be found on the East and West coasts of the United States, thus far associated only with Fucus. In addition, we found several strains of these organisms each of which, though fertile in intrastrain crosses, appeared infertile with all other isolates. A continuation of these studies has revealed another biologic species of wide geographic distribution (Taiwan, California, Florida, New York) and apparently associated with sea weeds other than Fucus.

Notes: SYNOPSIS. The effect of pretreatment with Isospora felis and bacillus Calmette-Guérin (BCG) on the reexcretion of Toxoplasma gondii occysts was studied in 16 coccidia-free cats. The following conclusions were drawn: (A) Chronically T. gondii-infected cats reexcreted T. gondii oocysts after superinfection with I. felis, and this reexcretion was prevented in cats infected with I. felis before T. gondii infection. (B) Administration of BCG before Toxoplasma infection had no apparent effect on the outcome of the infection.

Notes: SYNOPSIS Previous surveys of feral Drosophila melanogaster in Clarke County, Georgia, indicated 10 to 30% of the flies were parasitized with Herpetomonas ampelophilae. In the present study, herpetomoniasis in D. melanogaster reared in population cages rose from 0.01% to 90% in 14 days. The infection fluctuated between 5% and 100% during the 250 days in which the ageledeme was maintained. Herpetomonas were found endotrophically, peritrophically, and in the Malpighian tubules. In population cages, although there were sporadic rises in percentages, peritrophic and Malpighian tube infections usually remained low. Endotrophic infections often reached 100%, with individual flies being heavily parasitized. Although Chatton felt that several species of Herpetomonas inhabit a single species of Drosophila, we suggest that all the Herpetomonas in D. melanogaster be referred to as H. ampelophilae.

Notes: SYNOPSIS Experiments were designed to study intestinal pathophysiologic changes associated with coccidial infections in mammalian hosts. Pairs of male Sprague-Dawley rats were killed at various times postinoculation (PI) with 104 or 106 sporulated occysts of Eimeria nieschulzi. The small intestine from each rat was removed, weighed, measured, and divided into thirds. From the middle 11 cm of each third, one cm was fixed for histologic examination. Mucosa was scraped from the remaining 10 cm and was assayed for protein content and for peroxidase, sucrase and trehalase activities. Infection with E. nieschulzi was associated with increased mass of the small bowel. Histologically, crypt depth throughout the small bowel was significantly greater (P≤ 0.005) in infected rats than in non-infected ones on PI days 8 and 16. Villus height did not change drastically during low-dose infections (104 oocysts) and varied during high-dose infections (106 oocysts). As a result of these morphologic changes in the mucosa, crypt/villus ratios were usually significantly greater (P≤ 0.005) in all infected rats throughout the small bowel. In general, increased gut weight and changes in crypt and villus dimensions became evident by PI day 2, were most pronounced at PI day 8, and began to return to control values by PI day 16. Peroxidase, sucrase, and trehalase levels equaled or were slightly higher than in controls on PI day 2, dropped significantly below controls (P≤ 0.05) by PI day 8, and returned to, or exceeded control levels by PI day 16. The intensity of all changes was directly dose-dependent.

Notes: SYNOPSIS Random examination of domestic animals revealed the frequent presence of free-living amebae in their bodies. In diseased or dead cows, dogs, pigs, rabbits, pigeons, and turkeys 15 strains of amebae were found, belonging to the genera Acanthamoeba (A. polyphaga), Hartmannella (H. vermiformis), and Vahlkampfia (V. avara, V. enterica, V. inornata)., They were usually accompanied by other infectious agents in different parts of the host bodies. Pathogenicity of 3 isolates could not be demonstrated by inoculation of laboratory animals.Some features of the isolates differed from those previously known for members of these genera. These strains may be considered amphizoic amebae according to Page (1974).

Notes: SYNOPSIS In a hologamy-like process observed in Oxytricha hymenostoma, 2 cells belonging to complementary mating types fused and appeared to contribute equally to the macronuclei of the organism resulting from the fusion. The process was characterized by the absence of micronuclear division and by fusion of the macronuclei of the 2 partners. True conjugation involving micronuclear meiosis was not observed in O. hymenostoma. The biologic significance and the possible adaptive role of the hologamy-like process are discussed.

Notes: SYNOPSIS The mesenteric microvasculature was studied in rats and rabbits infected with Trypanosoma congolense. By examining vessels in the living animals, trypanosomes were observed to adhere to vessel walls by their anterior ends. It was evident from stained preparations of the vessels that the microcirculation contained 4–1400 times as many trypanosomes as were free in the cardiac blood. Parasites were more numerous in very small vessels than in larger vessels, and they were clustered in groups within the small vessels. The localization of T. congolense in the microvasculature is demonstrated and it is shown that this localization is established by attachment of the organism to the vessel wall.

Notes: SYNOPSIS The quantitative direct fluorescent antibody (QDFA) methods were employed for the antigenic analysis of bloodstream forms and culture procyclics of 2 variants, TRUM (Trypanosome Research University of Massachusetts) 106 and TRUM 107, of Trypanosoma brucei brucei. Intact and trypsinized trypanosomes were studied. It was demonstrated that: (A) The specific variant antigens are localized in the surface coat of bloodstream trypomastigotes. (B) In addition to the common antigens shared by bloodstream forms and culture procyclics, there are also certain antigens unique to these latter stages. (C) Still another group of antigens. not found in the culture procyclics, appears to be shared by the bloodstream forms, irrespective of their variant-specific antigens. These antigens may be present in part in the coat or on the cell membrane and in part within the cytoplasm. (D) Irrespective of the bloodstream-form variant from which they are derived, the procyclics are antigenically the same. The QDFA results are analyzed statistically and discussed in the light of the available literature.

Notes: SYNOPSIS Chemical analysis of axenic cultures of Hymenomonas sp. reveals that the degree of coccolith calcification is inversely proportional to the concentration of available nitrogen sources in the medium. This relationship makes possible a useful degree of control over the organism's calcifying activities. In addition, a possible selective advantage of such a relationship in nature is suggested.

Notes: SYNOPSIS Enhanced esterase C activity could be demonstrated by starch gel electrophoresis in various stocks of Paramecium spp. (P. primaurelia stocks 90 and 540, P. biaurelia stock 93, P. tetraurelia stock 29. P. pentaurelia stock 87, P. octaurelia stocks 31 and 300, and P. multimicronucleatum species 3, stock 8 MO) grown in Adaptation Medium. This esterase, however, was barely detectable when they were cultivated in Axenic Medium. Addition of trypticase to Adaptation Medium resulted in reduction of esterase C in the ciliates. This effect is ascribable to Na acetate present in trypticase. Since esterase C increased with the decrease in acetate concentration (as estimated by gas-liquid chromatography) during growth of Paramecium, acetate appears to be utilized by the cells. Sensitivity of esterase C to acetate occurs in all 6 species of Paramecium examined. Different stocks within a species may have different levels of sensitivity; in one case this is genetically determined. The results emphasize the importance of controlling and manipulating growth conditions for the assessment of inter- and intraspecies variations in the isozymes of Paramecium.

Notes: RESUME. L' étude ultrastructurale de la grégarine Gregarina blaberae a été entreprise après mise au point d'un protocole d'infestation expérimentale de larves vierges de Blattes, Blaberus craniifer. Les observations en microscopie électronique, effectuées en fonction du temps, ont permis de suivre le développement du sporozoïte, ainsi que la croissance et l' évolution du trophozoïte.La croissance est spectaculaire puisqu'en 18 jours elle entraîne la transformation du germe infectieux ou sporozoïte (L = 15 μm, φ=1 μm) en un céphalin—trophozoïte fixéà l' épithélium intestinal—de 250 μm de longueur pour un diamètre de 65 μm. L'organisation ultrastructurale du sporozoïte ne diffère pas de celle de la plupart des sporozoïtes des autres sporozoaires étudiés jusqu' à présent, le conoïde et les corps denses sont présents. La paroi est trimembranaire. toutefois le complexe membranaire interne présente quelques interruptions. Les premiers dictyosomes s' élaborent à partir de l'enveloppe nucléaire. La migration du noyau et des corps denses, puis la régression de toutes les formations caractéristiques du sporozoïte et l' établissement d'une zone corticale venant coiffer l' épimérite, ont lieu dans les 48 heures suivant l'infestation et marquent la transformation sporozoïte-céphalin.L' évolution du céphalin, se poursuit par la formation des ébauches des plis épicytaires qui s'effectue à partir du 3éme jour du développement à la base du deutomérite. Un système régulier de plis longitudinaux ou épicyte s' établit ainsi sur toute la partie extra-cellulaire de la grégarine. Dès les 4éme-5éme jours de développement, un réseau vacuolaire et un chondriome important se différencient dans l' épimérite, tandis qu'un septum de nature fibrillaire isole le protomérite du deutomérite. Le stade suivant—à partir du 6éme jour—est marqué par une ségrégation du matériel glucidique au niveau de ces 2 segments.Le modèle étudié permet de préciser le rôle de l' épimérite dansla nutrition du parasite, l' évolution du chondriome et des membranes corticales au cours de la phase de croissance végétative des grégarines polycystidées.

Notes: SYNOPSIS. Stomatogenesis was studied in the heterotrich ciliate Blepharisma japonicum stained with protargol. During binary fission not only is a new oral apparatus made for the posterior daughter, but the already existing oral apparatus of the parent cell is reorganized, i.e. partially disassembled and then subsequently reassembled to provide a functional feeding apparatus for the anterior daughter cell. These morphogenetic events, requiring 21/2 to 3 hr, are complete by the time the anterior and posterior daughters separate.In preparation for division, an oral anlage is formed by the rapid proliferation of kinetosomes along 4–5 stomatogenic kinetics directly subtending the cytostome. This field of randomly oriented kinetosomes ultimately gives rise to the feeding apparatus of the posterior daughter cell. Early in division, the oral anlage separates into 2 longitudinal fields of kinetosomes: one is destined to give rise to the undulating membrane and the other forms the adoral zone of membranelles. Shortly after the anlage is established posterior to the cytostome, reorganization of the existing functional mouth is initiated. The morphologic changes associated with this dedifferentiation-redifferentiation sequence lead to the formation of an oral apparatus for the anterior daughter and cannot be distinguished from those characteristically seen during physiologic reorganization.

Notes: SYNOPSIS. The effects of age and sex of the cat on oocyst shedding, multiplication of Toxoplasma gondii in tissues of cats, and acquisition of immunity were investigated after oral inoculation of cats with Toxoplasma cysts. Twenty-five cats varying in age from 1 week to 39 months were killed 7-97 days after inoculation with T. gondii. Homogenates of brain, heart, mesenteric lymph nodes, retina, and blood from these cats were inoculated into mice to test for Toxoplasma infectivity. Toxoplasma was isolated more frequently and in higher titers in mice receiving inocula from cats of the youngest age group (1 week old). Toxoplasma gondii was isolated from tissues of only 2 of 21 cats older than 2 months (at the time of inoculation), although all of the animals shed oocysts within 1 week after ingesting the parasites.The number of oocysts shed varied among littermates of the same sex and between sexes. Generally, cats younger than 12 months shed more oocysts than older cats. The number of oocysts shed by older cats varied considerably; males generally shed more oocysts than the females. However, the numbers of cats examined were too small for statistical comparison. Nevertheless, the observations suggest that cats older than 12 months should not be used in experiments where numbers of oocysts shed is critical.

Notes: SYNOPSIS. Changes in the metabolism of Crithidia fasciculata ATCC 11745 when grown in the presence of ethidium bromide were studied. Ethidium bromide-grown cells had decreased respiratory activity as measured by oxygen consumption. More than 50% of the organisms cultivated in a defined medium containing 1.0 mg/liter of ethidium bromide became dyskine-toplastic and had decreased activities of particulate succinate and NADH-linked dehydrogenases as well as of soluble isocitrate dehydrogenase. These cells also had increased activities of particulate α-glycerophosphate dehydrogenase, soluble α-glycerophosphate dehydrogenase, malic enzyme, hexokinase, and malate dehydrogenase. Ethidium bromide-grown cells had a lower level of ATP and contained less DNA than cells grown in its absence.

Notes: SYNOPSIS. Rats inoculated with 10,000 sporulated oocysts of Eimeria nieschulzi had significantly higher total leukocyte counts on postinoculation days (PI) 1, 5, 6 and 7 when compared to control rats. Relative and absolute neutrophil counts increased concomitantly with a decrease in the relative lymphocyte levels in E. nieschulzi-infected rats on PI day 7. Absolute and relative neutrophil counts in infected rats on PI days 7 and 8 were closely correlated with the host's total oocyst discharge. The E. nieschulzi infection had no significant effect on the relative or absolute levels of monocytes or eosinophils. The described changes in leukocyte levels were not paralleled by a significant change in the erythrocyte count.

Notes: SYNOPSIS. Experiments were designed to test whether or not intestinal transit time increases significantly during severe coccidiosis in the rat. Intraduodenal catheters were surgically implanted into 25 rats. Six to 12 days after surgery 11 rats were inoculated orally with 104 sporulated oocysts of Eimeria nieschulzi Dieben, and 11 were inoculated with 106 oocysts; 3 rats were retained as uninfected controls. At 2, 4, 8, 9, and 16 days postinoculation (PI) Na251CrO4 was injected through the catheter into the duodenum of fasted rats and allowed to progress through the small bowel for 15 min, at which time the rats were killed. The distribution of 51Cr in the gut was plotted as a function of gut length. The leading edge of radioactivity traversed 70% of the gut length in controls, and ∼ 50–60% in parasitized rats on days 2, 4, 8, and 9 PI. Also, a reflux of gut contents, as evidenced by radioactivity in the stomach, occurred early (PI days 2 & 4) in rats infected with 104 oocysts and throughout patency in rats infected with 106 oocysts.A 2nd study was undertaken to determine if chemically induced suppression of gut transit time during early infection would enhance infectivity as measured by increased parasite fecundity. Nine rats were injected subcutaneously with an antidiarrheal agent, Loperamide®, known to slow small bowel motility significantly. Another group of 9 control rats was injected with the ethanol-propylene glycol solvent. Ten min after injection, all rats were inoculated per os with 104E. nieschulzi oocysts. The daily number of oocysts discharged/rat was followed from PI days 5–11. Patency began for all rats on PI day 7. The total number of oocysts discharged by the drugged rats as compared with controls was not significantly different.

Notes: SYNOPSIS. The effect of pretreatment with BCG strain of Mycobacterium tuberculosis or Hammondia hammondi 21 days before challenge with lethal doses of Toxoplasma gondii and Besnoitia jellisoni was studied in hamsters. The results indicated that the intracardial administration of BCG provided no protection against either T. gondii or B. jellisoni. The hamsters immunized with H. hammondi survived challenge with 104 lethal doses of T. gondii but only 1 lethal dose with B. jellisoni, indicating strong cross protection between H. hammondi and T. gondii and only a marginal one between H. hammondi and B. jellisoni.

Notes: SYNOPSIS. Autoclavable, natural particulate media simplify axenic cultivation of tetrahymenid ciliates and presumably favor selection for phagotrophy. Viability is at least 2 months at room temperature (24–26 C) for the lipid-sensitive tetrahymenids Tetrahymena setosa, T. corlissi, T. paravorax, T. limacis, and T. patula, also for T. rostrata and (at 12 C), for strains of the T. pyriformis complex and Glaucoma chattoni. A typical medium consists of crude soy “lecithin”+ skim milk powder +Saccharomyces cerevisiae cells. Other useful particules readily available commercially are: whole liver powder, cells of Micrococcus lysodeikticus and Escherichia coli, and powdered residue of liver which had been extracted with 70% ethanol (liver #2). Preliminary experiments indicate that some of these media are suitable for the maintenance of Paramecium octaurelia stock 299S and Colpidium campylum. Such mixtures may serve as points of departure for devising media for more fastidious phagotrophs.

Notes: SYNOPSIS. Trypanosoma theileri was cultivated at 37 C in bovine bone marrow cell culture through 50 consecutive subcultures. Medium 199, supplemented with Bacto-peptone, vitamin B12, and fetal bovine serum, was utilized both for primary and continuous cultivation. The number of trypanosomes produced in culture averaged 8 × 106 (1–26 × 106) trypanosomes/ml. In each subculture the organisms divided as epimastigotes and transformed into trypomastigotes; a round form was observed during the stationary and declining phase of growth. Gradual changes such as increased generation time, size reduction, and decreased trypomastigote production were observed as subculturing progressed. Cultured trypanosomes were infective for the bovine through the 48th serial transfer and could be cultivated at 26 C.

Notes: SYNOPSIS. Chloroplast development is inhibited in Euglena gracilis strain Z, when greened in a medium containing glucose. This inhibition is reflected not only in the pattern of chlorophyll accumulation but also in the chloroplast ultrastructure and activities of the 2 light reactions of photosynthesis. Chloroplasts of cells greening in the presence of glucose are delayed in déveloping certain structures. Photosystem I activity develops at about the same rate as that of the controls during the first 48 h of greening, after which it develops at a slower rate. The rate of development of photosystem II activity in cells greening in a glucose medium lags considerably behind that of the controls until the later hours of greening. There are similarities between glucose inhibition and chloramphenicol inhibition of chloroplast development. Glucose may inhibit a step in chloroplast development ultimately controlled by the chloroplast genome.

Notes: SYNOPSIS. Gametocytes differentiated from ring-stage parasites in microcultures of human blood infected with Plasmodium falciparum. Immature gametocytes could be distinguished morphologically from late asexual trophozoites after ∼ 40 h of culture. Differentiation into crescentic forms took several days and the incorporation of [3H]-isoleucine by developing gametocytes was demonstrated. About 1% of red cells contained gametocytes at the maximum densities attained. Differentiation of gametocytes occurred either directly from rings placed in culture or from the progeny of subsequent cycles of schizogony and invasion in vitro. The latter occurrence was confirmed by the development of gametocytes in marker fetal red cells added to cultures, although fetal red cells provide a less favorable environment than those with HbA for growth of the parasites.

Notes: SYNOPSIS. Incorporation of 14C-labeled biopterin into Crithidia fasciculata was inhibited by 1 mM colchicine or lumicolchicine. These substances do not penetrate the cell membrane, hence they cannot interact with the subpellicular microtubules. In view of this, interference of colchicine with biopterin transport must occur on the outer surface of the cell membrane. Binding of colchicine to Crithidia was not temperature-dependent and did not exhibit saturation kinetics. These facts exclude a binding as in the case of tubulin, or similar proteins which may be present in the membrane. The results suggest an inhibition reflecting steric hindrance of the biopterin carrier system.

Notes: SYNOPSIS. DNA of Naegleria gruberi strain NEG, grown in axenic culture, forms a band at a density of 1.6912 in CsCl gradient and has a GC content of 31.8%. Incorporation of [3H]thymidine into DNA is much reduced in differentiating Naegleria immediately after the stimulation to transforms, primarily because of the reduction in thymidine uptake by differentiating cells. In addition, there is a marked decrease in the rate of incorporation of [3H]thymidine and [3H]uracil into DNA at from 45 to 60 min after the stimulation for differentiation. This decrease in the rate of precursor incorporation into DNA appears to be due to the differentiation-dependent cessation of nuclear DNA synthesis. The differentiated phenotype (the flagellate) emerges at ∼ 70 min after the stimulation, and over 90% of the population differentiates within the next 30 min. Synthesis of mitochondrial DNA is detectable until 190 min after the stimulation. Since the S phase of Naegleria lasts ∼ 180 min, some cells in the population must cease synthesizing nuclear DNA in the middle of the S phase.

Notes: SYNOPSIS. A method was developed for the isolation and purification of crystalline, highly refractile bodies found in the cytoplasm of a symbiote-free strain of the marine hymenostome ciliate, Parauronema acutum, strain 110–3. Chemical analysis of the purified refractile bodies revealed an abundance of the purines, hypoxanthine and guanine. It was evident from studies involving the use of 14C-labeled precursors that both hypoxanthine and guanine are derived from higher purine derivatives. We postulate that these bodies are excretory in function and that guanine and hypoxanthine are major endproducts of purine metabolism of P. acutum.

Notes: SYNOPSIS Paraphysomonas vestita (Stokes), a colorless flagellate, has silicified external scales. In this study EDAX analysis of the scales confirmed earlier experimental evidence that silicon is the major component of the scales. The scales are formed in the endoplasmic reticulum of the cytoplasm and carried to the plasmalemma in vesicles. The flagellate is euryhaline growing in a range from 2.6X seawater to near distilled water. From the salinity data it appears that Paraphysomonas vestita is the same as Paraphysomonas imperforata Lucas. A GeO2 concentration of 2.0 mg l-1 (19.2 μM Ge) results in complete inhibition of growth.

Notes: SYNOPSIS Seven monocystid gregarine parasites including 6 new species are described from the perivisceral coelom and seminal vesicles of Nigerian earthworms, which have not been so far investigated for monocystid parasites. The new species are: Apolocystis iridodrilii sp. n. from Iridodrilus preussi and Iridodrilus roseus; Apolocystis libyodrilii sp. n., Monocystis abegbei sp. n., Monocystis libyodrilii sp. n., and Zygocystis violacea sp. n. from Libyodrilus violaceus; and Nematocystis bunmii sp. n. from Heliodrilus lagosensis. Apolocystis herculea (Bosanquet) was recorded from Libyodrilus violaceus.

Notes: SYNOPSIS Herpetomonas sp. was found repeatedly in the Malpighian tubules of laboratory-reared male and female Aedes aegypti and Aedes albopictus in Malaysia. The flagellates occurred irregularly, in batches, and were absent during long periods. The data suggest an exogenous source of infection for the mosquitoes, presumably from another insect, probably of another genus.Thirty to 40% of the flagellates of Aedes contained intracytoplasmic rod-shaped structures strongly resembling bacteria. These were found often in groups suggesting intracellular multiplication. They were passed to the Herpetomonas daughter cells during division. Parasitism of Aedes by Herpetomonas is extremely unusual, only one previous record, an inconclusive one, having been found. Parasitism by Herpetomonas containing bacterium-like rods has apparently never been reported.

Notes: SYNOPSIS Monolayers of Embryonic Bovine Trachea (EBTr) cells were inoculated with Isospora canis Nemeséri spcrozoites. As penetration commenced, they were fixed, stained with OsO4-ruthenium red, dehydrated, embedded and sectioned in situ. Examination by electron microscopy revealed that host cell membranes remained intact during penetration. The sporozoites caused an invagination of the cell's plasmalemma until the parasites were entirely within the cell, after which the invagination was sealed by short pseudopodia enclosing the parasite within a membrane-lined vacuole inside the cells. Rhoptries and micronemes, which appeared as branched elements of the same network, became less tortuous near the conoid and often became empty or partially empty during penetration. Concurrent with the appearance of these partially empty rhoptries, vesiculations were seen in the host cell cytoplasm opposite the apical tip of the sporczoite. Constrictions of the sporozoite during entry were probably due to bands of microfilaments beneath the plasmalemma and elsewhere in the cytoplasm of the host cell.

Notes: SYNOPSIS As determined by their ability to exflagellate and round up, it took the macrogametocyte and the microgametocyte of Haemoproteus columbae in pigeons 68 and 116 h, respectively, after patency to reach maturity. Pigment granules appeared in the undifferentiated gametocytes 8 h after invasion of blood. Vacuoles were observed in young gametocytes and persisted in the older forms. The growth curve of H. columbae is close to the sigmoidal curve for growth in protozoa. Multiple infection was noticed in pigeons with high levels of parasitemia, but no more than 2 gametocytes reached maturity; such multiple infections were rare in relapses. The sex ratio of the gametocytes was 1:1. Strong lateral displacement of the nuclei of infected erythrocytes was the rule; hypertrophy was negligible.

Notes: SYNOPSIS In a culture system of Paramecium bursaria, virus particles were found in large number. The particle was able to infect and multiply in certain cells of the zoochlorella, an intracellular symbiotic alga of P. bursaria. The infective particle, designated as zoochlorella cell virus (ZCV), was icosahedral and 120–180 nm in edge to edge diameter. The ZCV particle was found to differ from any of the already established viruses attacking the green and the blue-green algae. Within the system where P. bursaria cells were growing, ZCV particles were detected in the depression of the pellicle, among the cilia growing in the cytopharynx, and in the food vacuole of P. bursaria. ZCV particles were infective only for the zoochlorella cells which were recently released from the cytoplasm of P. bursaria. The multiplication process of ZCV comprised the adsorption of the particle to the cell wall of the zoochlorella, the penetration of nucleic acid into the host cell interior, the replication of viral constituents, the maturation of viral particles and their final release by the burst of the zoochlorella cell. ZCV particles appeared only in the cytoplasmic region of the zoochlorella cell in which many ribosomes were distributed. A possible ecosystem among the 3 members consisting of P. bursaria, zoochlorella and ZCV is discussed.

Notes: SYNOPSIS A method is described for the electrophoretic analysis of proteins or RNAs from individual amebae. The method is based on fluorographic autoradiography of semi-micro polyacrylamide gels in which [35S]methionine or [3H]uridine materials from single cells have been subjected to electrophoresis. The method is more sensitive and provides better resolution than previous methods for single cells. It is suitable, also, for quantitation of the separated components.

Notes: SYNOPSIS SDS polyacrylamide gels of the ciliary membrane proteins of Tetrahymena thermophila revealed 5 major peaks and 11 minor protein peaks ranging in molecular weight from below 20,000 to above 250,000. The peaks resembled those found for ciliary membrane proteins of Paramecium aurelia..

Notes: SYNOPSIS Evidence obtained by total hydrolysis, partial acetolysis, periodate oxidation, as well as treatment with amylase, emulsin, and Trichoderma virideβ-(1→4)-glucanase, verified that the alkali insoluble component of Acanthamoeba castellanii was pure β-(1→4)-glucan. The weight average chain length of the cellulose varied from DP = 3170 to DP = 4130 (mean DP = 3480) with polysaccharide obtained from seven seemingly identical cultures. Isolation of the cyst-wall cellulose by nondegrading means indicated that alkali extraction was not depolymerizing the polysaccharide. Fractionation of cellulose obtained from a single culture produced fractions from DP = 550 to DP = 4550 (mean DP = 3280; 98.7% of the original cellulose), indicating that the cellulose is polydisperse.

Notes: SYNOPSIS The fatty acids lauric, myristic, and oleic, as well as long-chain bases (LCBs) obtained from sphingolipids, and Tween 80 “spare” the requirement for folate by Tetrahymena pyriformis W. Since LCBs are metabolized by the ciliate to ethanolamine phosphate and fatty aldehydes which can be converted to either fatty acids or fatty alcohols, the latter compounds are used as precursors of phospho- and phosphonolipids and ether phospholipids. It is suggested that lipid biosynthesis is a rate-limiting step in growth of the ciliate as is the folate concentration. Removal of one restraint on growth rate mimics the effect of increased folate concentration. Alternatively, if the enzymes responsible for lipid synthesis are repressible, the presence of exogenous fatty acids would make available more formylmethionyl-tRNA for the initiation of synthesis of other proteins.

Notes: SYNOPSIS. A trypanosomatid flagellate was isolated from the musciod fly Muscina stabulans (Fallén). Cloned cultures of this organism contained promastigotes, opisthomastigotes, and froms containing a long flagellum doubled or coiled within the cell but not protruding outside. These latter forms we are designating endomastigotes. The presence of these hitherto underscribed endomastigotes along with other morphologic and growth characteristics suggest that this is a new species for which the name Herpetomonas mariadeanei is proposed.

Notes: SYNOPSIS. Isopora gallicolumbae sp. n. is described from Beccari's ground dove, Gallicolumba beccarii Salvadori, in Papua New Guinea. The ellipsoidal oocysts average 16.0 × 20.0 μm. The oocyst wall is light green, single-layered (∼ 0.8 μm), and becomes distorted within 10 min in sugar solution. Micropyle and oocyst residuum are absent; one polar granule is present. Sporocysts are ovoid, 8.0 × 12.0 μm. with prominent conical Stieda body. Sporocyst residuum is a spherical mass (∼ 5.0 μm) of lighter and darker granules. This is the first species of Isospora reported from a host in the avian order Columbiformes.

Notes: Books Review in this article:Dawes, Ben, ed. 1977. Advances in Parasitology. Vol. 15. Academic Press, 111 Fifth Ave., New York NY 10003, USA. xx + 409 pp. $36.25.Kcan, H . H., Mott, I(. E. S: Russell. A. J. eds. 1978. Tropical Medicine and Parasitology. Classic Ii1ccstigation.c. 1'01s. I and 11. Corncll Univ. Press, 124 Roberts PI., Ithaca XY 14850. xxiii + G77 pp. $.50.00.Reissig, J. L., ed. 1977. Microbial Interactions. Vol. 3 of Receptors and Recognition, Series B. Chapman and Hall, London. + 436 pp. $39.50.'Taylor, Angela E. R. Sr Muller. R.: eds. 1978. Thc Rclccance of ParaJitology to Human Welfare Today. Symbosiuin .Vo. 16 of the British Society for Pnrasitolo, qy. Blackwell Scientific Puhlications, Osney Mead, Oxford 0 5 2 OEL. England and J. B. Lippincott Co., East Washington Squaw, Philadelphia PA 191 0.5, L viii + 135 pp. $18.75.

Notes: SYNOPSIS. Oocysts of Eimeria nieschulzi from the laboratory rat, Rattus, norvegicus, were studied by scanning and transmission electron microscopy. Oocysts had a rough outer wall with apparent random depressions. The oocyst wall is composed of 2 layers: an osmiophilic outer layer consisting of a rough external and smooth internal surface, and a relatively thick, electron-lucent inner layer. The outer layer is composed of a dense, coarsely granular matrix. The inner layer consists of homogeneous fine granular material interspersed with coarse osmiophilic granules and contains one closely applied membrane on the outermost surface. Several raised lenticular areas are seen on the coarse outer surface of the inner layer. These layers are 102 (75–128) and 176 (135–204) nm thick, respectively.The sporocyst wall is thin, consisting of 3 to 4 unit membranes, and measures 27 (18–34) nm thick.

Notes: SYNOPSIS. During gametogenesis mother individuals of Hastigerina pelagica (d'Orbigny) undergo significant morphological changes. Thirty h before gamete release, the cytoplasm changes from pale orange to bright red, possibly due to transport of stored lipids from the inner region to more peripheral parts of the cytoplasm. During the next 10 to 15 h the bubble capsule which surounds the calcareous shell is discarded. After all bubbles have disappeared, the individual sheds its spines by resorbing the spine bases close to the shell surface.A single mother nucleus divides into some hundreds of thousands of gamete nuclei within a span of ∼ 20 h. A bulge of cytoplasm is extruded from the aperture and increases in size during the next 5 to 10 h. This bulge consists of cytoplasmic strands in which gametes and spherical bodies are embedded. The gametes and spherical bodies mature and are released during the afternoon and early evening. The gametes have 2 unequal acronematic flagella. A previously undescribed structure in foraminiferal reproduction is the spherical body which consists of a large vacuole surrounded by a thin cytoplasmic layer in which several nuclei, various typical cell organelles and multiple flagella are present. The spherical bodies are believed to play a role as receptacles of waste material, possibly including residual digestive enzymes, thereby protecting the gametes from lysis during the reproductive process. Fusion of gametes and further development into the next generation have not been observed.

Notes: SYNOPSIS. The excystation of sporozoites from intact Toxoplasma gondii oocysts or mechanically released sporocysts was studied by light and electron microscopy. Both intact oocysts and free sporocysts excysted in 5% bovine bile in 0.9% NaCl solution after 30–60 min incubation at 37 C. Sporozoites were first activated in either intact sporocysts or oocysts within 2–12 min of incubation in bile. Sporozoites escaped from sporocysts through 4 plate-like sutures in the sporocyst wall, and from the oocyst as the oocyst wall ruptured at one or more points.

Notes: SYNOPSIS. Treatment of Euglena gracilis with the cationic detergent CTAB at concentrations of 0.05 mM or higher selectively inhibited the ability of the cells to respond with flagellar reorientation to a sudden decrease of light intensity (step-down photophobic response). The ability to respond similarly to an increase in light intensity (step-up photophobic response) was unaffected even at detergent concentrations at which the step-down response was completely inhibited. Electron microscopy of cells treated with 1.0 mM CTAB revealed selective destruction of the membrane of the reservoir and flagellum. No selective effects upon the step-down or step-up photophobic responses were found upon treatment of the cells with Triton X-100.

Notes: SYNOPSIS. The erythrocytic cycle of the human malaria parasite, Plasmodium falciparum, was examined by electron microscopy. Three strains of parasites maintained in continuous culture in human erythrocytes were compared with in vivo infections in Aotus monkeys. The ultrastructure of P. falciparum is not altered by continuous cultivation in vitro. mitochondria contain DNA-like filaments and some cristae at all stages of the erythrocytic life cycle. The Golgi apparatus is prominent at the schizont stage and may be involved in the formation of rhoptries. In culture, knob-like protrusions first appear on the surface of trophozoite-infected erythrocytes. The time of appearance of knobs on cells in vitro correlates with the life cycle stage of parasites which are sequestered from the peripheral circulation in vivo. Knob material of older parasites coalesces and forms extensions from the erythrocyte surface. Some of this material is sloughed from the host cell surface. The parasitophorous vacuole membrane breaks down in erythrocytes containing mature merozoites both in vitro and in vivo. Merozoite structure is similar to that of P. knowlesi. The immature gametocytes in culture have no knobs.

Notes: SYNOPSIS. The suctorian Heliophrya erhardi (Rieder) Matthes is attached to the substrate by the flattened ventral side of the cell body. The dorsal is covered by a pellicle composed of 3 unit membranes. Below the pellicle is a 0.4–0.8-μm thick epiplasm composed of 6–8-nm thick fibrils. Microtubules form a network beneath the epiplasm. The epipalsm is penetrated by tube-like pellicular pits, which are lined by the cell membrane and end beneath the epiplasm in a saccule-like enlargement. During conjugation, 2 neighboring organisms form cytoplasmic processes which come into contact and fuse, thus forming a cytoplasmic bridge between the 2 cells. Around the bridge the pellicles of both organisms fuse, and the partners become united by a continuous common membrane system. Across the entire conjugation bridge the 2 fused epiplasms form a septum. Tube-like structures can be seen lying partly in the epiplasmic septum and partly in the adjacent cytoplasm. These structures are open at both ends and represent remnants of the pellicular pits. No trace of the original pellicular membranes can be found at the fusion area within the epiplasmic septum. The cytoplasm of the conjugation partners is separated only by the fused epiplasms forming the epiplasmic septum.

Notes: SYNOPSIS. At temperatures below 15 C, the contractile vacuole cycle of Amoeba proteus includes a presystolic plateau. The hypothesis attributing this plateau to a steady-state equilibrium between active filling processes and osmotic losses of water from the vacuole into the cytoplasm has been expressed in an equation predicting vacuolar diameter as a function of time for the later part of the cycle. Computer-generated model cycles have been compared with actual recorded cycles at 15 C, 10 C and 5 C and conditions of best fit were determined. Statistical analysis shows that recorded cycles are quite compatible with the steady-state hypothesis.

Notes: SYNOPSIS. Living, intact bloodstream trypomastigotes and culture procyclic forms of Trypanosoma congolense were tested for agglutination with the lectins concanavalin A (Con A), phytohemagglutinin P (PP), wheat germ agglutinin (WGA), soybean agglutinin (SBA), and fucose binding protein (FBP). Similar experiments were conducted with living bloodstream and culture forms treated with trypsin or dextranase. Parasites were incubated for 30 min at 25 C in various concentrations of each lectin, then examined for agglutination by dark-field microscopy. Control preparations consisted of parasites incubated alone or with 0.5 M of the specific competing sugar, with or without the corresponding lectin.Electron-microscopic localization of lectin binding sites on the surface of intact and dextranase-treated bloodstream and intact culture forms was accomplished with Con A, reacted with horseradish peroxidase (HRP) and then diaminobenzidine (DAB). In addition, FBP and SBA were coupled to HRP, then utilized for the localization of binding saccharides on the surface of blood-stream forms by the DAB technic. Similar studies were conducted with culture procyclics incubated with WGA-, SBA, PP- or FBP-HRP conjugates and then reacted with DAB. Controls were utilized to confirm the sugar specificity of all positive reactions.Intact living bloodstream forms were agglutinated in a concentration-dependent manner with all the lectins tested. Agglutination levels were scored as Con A 〉 FBP 〉 WGA = PP = SBA. Sugars resembling α-D-mannose, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, and α-L-fucose are evidently present on the surface of the parasites. No agglutination was noted in any control preparations. Identical lectin-induced agglutinations were obtained with trypsin- or dextranase-treated bloodstream forms. Trypsin disrupted but did not entirely remove the surface coat of bloodstream forms, while dextranase did not alter the ultrastructure of the parasites. Con A-, SBA- and FBP-binding saccharides were distributed uniformly on the surface coat of intact bloodstream forms; a similar distribution of Con A receptors was noted also on the surface of dextranase-treated cells. No lectin-binding saccharides were visualized by electron microscopy on any control preparations. Intact, trypsin- or dextranasetreated, procyclics were agglutinated in a concentration-dependent fashion by Con A and WGA, but not by the other lectins tested. Control preparations did not agglutinate and the enzymes did not affect the ultrastructure of the parasites. Con A- and WGA-specifically binding saccharides were uniformly distributed on intact procyclics and control preparations were lectin-negative. Thus, T. congolense procyclics retained surface saccharides resembling α-D-mannose and N-acetyl-D-glucosamine but lost sugars resembling N-acetyl-D-galactosamine (or D-galactose) and α-L-fucose. The failure of dextranase to remove the lectin-binding saccharides from the surface of bloodstream and procyclic forms suggests that α-1,6-glucan bonds do not link these carbohydrates. The results are contrasted with lectin research on other trypanosome species and discussed with relation to the biology of T. congolense.

Notes: SYNOPSIS. The effect of osmotic pressure, different electrolytes and organic compounds on cyst formation in Acanthamoeba palestinensis has been tested. The optimal osmolarity for encystment was similar to that of the growth medium. Iso-osmotic solutions of NaCl, KCl, MgCl2, CaCl2, glycine and sucrose led to maximum cyst formation. The involvement of various agents in the induction of encystment is discussed.

Notes: SYNOPSIS. Cell lines of Acanthamoeba castellanii resistant to erythromycin (EryR), chloramphenicol (CapR), and oligomycin (OliR) have been isolated. These may be the first such mutants for A. castellanii. These mutants have been phenotypically stable for 2 years, surviving storage and vegetative multiplication in the absence of drugs. Resistance was specific for each drug, but double mutants (e.g. EryRCapR) were obtained by stepwise selection. Mutant frequencies were determined in multiwell plates; 〈10 colony forming units (CFU/105 amebas were observed in wild-type populations 12 days after incubation in 500 μg Ery/ml, 2.5 mg Cap/ml, or 15 μg Oli/ml. After 30 days, averages of 100 CFU/105 amebas were observed in Ery and Cap, whereas, frequencies for Oli remained unchanged. Frequencies for EryR and CapR were consistent with rates of recovery from these drugs in batch cultures. We were unable to obtain spontaneous mutants resistant to cycloheximide, emetine, 5-fluorodeoxyuridine, or ethidium bromide. EryR, CapR and OliR could be mitochondrial mutants.

Notes: SYNOPSIS. Rabbit Encephalitozoon cuniculi were propagated in vitro using rabbit choroid plexus (RCP) cells. The organisms reached maximum titer and numbers by 15 days. The source and in vitro passage level of RCP cells moderately influenced the sensitivity of the cells to infection. Cells less than 1 week old were significantly less sensitive than older cells. A moderate increase in infectivity for RCP cells was demonstrated with increasing organism passage level in vitro. Rabbit E. cuniculi were not affected by penicillin-streptomycin or gentamicin in the culture medium. The organism survived more than 9 days in buffer at 37 C and least 24 days at 4 and 20 C. Storage at -70 C or in liquid nitrogen was successful for at least 6 months. Encephalitozoon cuniculi survived 60 but not 120 min at 56 C. They were killed after 10 min of autoclaving and by 2% (v/v) Lysol, 10% (v/v) formalin and 70% (v/v) ethyl alcohol. The organisms survived at least 24 h at pH 9 or pH 4 and were not affected by sonication, freezing and thawing, or distilled water but lost significant infectivity after 24 h in CsCl or 40% (w/v) sucrose.

Notes: SYNOPSIS. Developmental forms of 2 strains of Babesia bovis (Babes) were studied in the tick vector Boophilus microplus (Canestrini). One strain (designated T) was shown to be infective for the tick, and the other (NT) to have lost infectivity for the tick, because of repeated blood passaging in cattle.Parasites of the 2 strains in gut contents of adult female ticks were similar during the first 16 h post-repletion (PR), but thereafter their structure differed. From 16–64 h PR, the majority of T strain parasites were spherical and without processes. During the next 32 h elongate forms and vermicules developed. Fission bodies were seen within epithelial cells of the gut by 96 h PR. T-strain parasites in gut contents decreased in number from ∼ 96 h and were difficult to find at 144 h, the time of the final observation.In contrast, NT strain parasites were plentiful throughout the period of observation. They were predominantly spherical, ranging in diameter from 1.5 to 15 μm. Forms with obvious processes measuring up to 81 μm in length were seen in large numbers at seemingly regular intervals from 16–144 h PR, suggesting that a process of development and divisions was being repeated. No vermicules or fission bodies were seen.T-strain, but not NT strain parasites, were seen in hemolymph and ova of the ticks and in their larval progeny. It is suggested that continuous blood passaging of the NT strain had resulted in selection of parasites incapable of penetrating gut epithelial cells of the tick.

Notes: SYNOPSIS. Shale oil retort water is obtained by centrifuging the oil/water emulsion produced by oil shale retorting. The ciliate Tetrahymena pyriformis was exposed to retort water; 2, 1, and 0.5% initially increased motility; longer exposures decreased motility. Three, 4, and 5% all decreased motility. Cell lysis was directly related to concentration; after 24 h, population densities were 0, 10, and 25% of controls for 2, 1, and 0.5% retort water, respectively. Oxygen consumption paralleled the motility pattern: at lower concentrations it increased initially but decreased with extended exposures while at higher concentrations it decreased rapidly. The most striking cytologic alteration of cells exposed to the toxicant occurred in the membranes; alterations of mucocysts and glycogen content were also observed, but mitochondrial changes were not. Population growth was affected at much lower concentrations than the other test indices. The growth of test populations reached a plateau at values inversely related to concentration: concentrations 〈0.4% had no effect on growth rate.

Notes: SYNOPSIS. The antigenically active glycoproteins (AAGP) released by Leishmania donovani strain 3S promastigotes into growth media and by amastigotes of this strain into the tissues, e.g. blood, of infected hamsters was found to consist of 6 to 7 antigenically distinct components. The antigenic activity of these glycoproteins was resistant to freeze-thawing, protease treatment, and purification by column chromatography using Sephadex G-100. This activity, however, was destroyed by Na periodate and altered by boiling; AAGP adhered firmly to Amicon filter (UM2). The antigenically active substances absorbed UV at 230, 260, 280 nm and gave positive Folin phenol, phenol sulfuric acid, and orcinol reactions. By gel diffusion, the component glycoproteins were found to form lines with concanavalin A and to give reactions of identity and partial identity with human red cells and Mycobacterium butyricum. The possible involvement of the antigenically active glycoproteins in pathogensis of kala azar is discussed.

Notes: SYNOPSIS. Six protozoa-free sheep, 3 fed alfalfa hay and 3 fed a concentrate diet, were inoculated with rumen contents from a steer fed the same alfalfa hay. All 24 species of protozoa in the inoculum became established in the sheep fed alfalfa hay, while only 9 species established in the sheep fed concentrate. Percentage species composition in the alfalfa-fed sheep was fairly similar to that of the inoculum. Rumen volumes of the alfalfa hay-fed sheep were significantly higher than those of the concentrate-fed sheep; however, fluid turnover rates were similar. Total protozoan numbers per ml of rumen contents were significantly higher in the concentrate-fed sheep, but after adjustment for rumen volume, there was no significant difference in the total number of protozoa in the rumen.

Notes: SYNOPSIS. When different antigenic variant clones are injected in equal numbers into white mice one variant clone always replaces the other. This phenomenon appears to be a predictable one, even under conditions analogous to a chronic infection. It is hypothesized that a constant ratio is approached between the number of cells of different antigenic serotypes present in a single population, in such a manner that there is always a major antigenic variant and minor populations of different antigenic variants. It is further suggested that these ratios can undergo rapid changes in response to changes in the environment, e.g. nutritional status of the host, changes in body temperature, antibody synthesis, etc. The changes in these ratios are discussed in relation to the mechanism(s) of antigenic variation.

Notes: SYNOPSIS. Development of Eimeria tenella was studied in primary cultures of chicken kidney cells maintained in Medium 199 lacking each of the following: vitamin A. biotin, p-aminobenzoic acid, folic acid, nicotinamide, Ca pantothenate, pyridoxine, pyridoxal, riboflavin, thiamin, ascorbic acid, calciferol, α-tocopherol, and menadione. Data obtained concerning numbers of mature schizonts or total numbers of parasites or both indicated that all of the vitamins are needed for 1st- and 2nd-generation schizogony, and all except calciferol and folic acid are needed for gametogony.

Notes: SYNOPSIS. Heme, intrinsically required by Trypanosomatidae, is unstable, especially in conventional alkaline (pH 7.2–8.0) media. Low solubility of heme in a pH 6.5 basal medium (developed to assay biopterin with Crithidia fasciculata) posed a problem: in media acidified during growth because of glycolysis, heme precipitated, perhaps contributed to acid-limited growth and interfered with densitometric estimation of growth. The remedy was to: replace glucose with less rapidly metabolized mannitol; distribute media in thin layers to promote oxidation of acetate, fumarate, and malate (presumably leaving an alkaline residue); and buffer heavily with histidine + Good zwitterionic buffers, and superimpcse physiological buffering by arginine + asparagine whose catabolism appeared to yield an excess of NH+4 over acid. Thereupon, Fe and Cu deficiencies sharply limited growth in the medium whose main chelators were: (a) 2,3–dihydroxybenzoic + 5-sulfosalicylic acids (which preferentially bind transitional elements at their higher valences; (b) malic and gluconic acids; and (c) histidine. With unconventionally heightened concentrations of Fe, Cu, and Mo (the latter serving as Cu buffer as well as nutrient per se), the hemin concentration could be lowered, widening the margin of safety for heme solubility. Growth then reached 1.4 × 108 cell/ml. This medium may serve to screen for ligands promoting uptake or release of Fe and Cu. The increased growth is a step towards improving the assay medium for biopterin and practical use of Crithidia to assay several B vitamins and essential amino acids for metazoa.

Notes: SYNOPSIS. Trichomitopsis termopsidis (Cleveland), a cellulolytic hindgut symbiote of the termite Zootermopsis, has been cultivated axenically under anaerobic conditions. The medium consists of cellulose, reduced glutathione, fetal calf serum, yeast extract, and autoclaved rumen fluid or autoclaved rumen bacteria, in a buffered salt solution the composition of which is based on an analysis of Zootermopsis hindgut fluid. The hindgut contents of surface-sterilized termites were inoculated into anaerobic buffer-containing cellulose and serum. Repeated passages yielded mixed cultures of T. termopsidis and termite hindgut bacteria. Flagellates were then inoculated into complete medium containing antibiotics, and after 2 passages, axenic cultures of T. termopsidis were obtained. Various nutritional supplements, including clarified rumen fluid or heat-killed bacteria of several known species failed to support the growth of T. termopsidis when substituted for autoclaved rumen fluid. The flagellates did not grow when any of several carbohydrates were substituted for cellulose. Electron microscopy of flagellates from axenic cultures revealed that cellulose particles and partially digested bacteria were present in food vacuoles. No endosymbiotic bacteria were present in the cytoplasm indicating that T. termopsidis does not depend on living prokaryotes for cellulose digestion. The results suggest that T. termopsidis possesses the enzyme cellulase.

Notes: SYNOPSIS. This is the first description of a method for growing axenized Entamoeba histolytica as colonies from single cells in agar suspension. Factors affecting the efficiency of colony formation included unknown characteristics of the amebal strain, age of cells used, and the type and concentration of agar employed. Colony formation was dependent upon filling deep vessels (culture tubes or tissue culture flasks) with agar, probably to maintain reduced oxygen tension, and upon solidifying the agar rapidly at 0 C. It was demonstrated in a study with the drug metronidazole that the agar colony method was useful for quantifying cell viability in drug testing.Eleven of 12 E. histolytica strains tested, as well as one Entamoeba terrapinae, one Entamoeba barreti, and 3 Entamoeba invadens strains formed colonies in agar suspension. E. histolytica-like amebae (Laredo type) and E. moshkovskii formed only tiny colonies in agar.

Notes: SYNOPSIS. Pyridoxine kinase enzyme activity was greatly increased in duckling erythrocytes infected with Plasmodium lophurae. Pyridoxine kinase activity in parasites freed from erythrocytes was much greater than that of uninfected erythrocytes. The apparent Km for pyridoxine of the parasite enzyme was 6.6 × 10-5 M whereas the host red cell enzyme Km was 1.9 × 10-6 M. Deoxypyridoxine inhibited host and parasite pyridoxine kinase activity with an apparent Ki of 1.5 × 10-6 and 8.6 × 10-6 M, respectively. These results suggest that the vitamin B6 metabolism of the malaria parasites is distinct and separate from that of the host erythrocytes.

Notes: SYNOPSIS. Twelve strains of Crithidia, which fall into 8 species, were tested for occurrence of enzymes of ornithine-arginine metabolism. The following enzymes were investigated: arginase, ornithine carbamoyltransferase, argininosuccinate lyase, citrulline hydrolase, arginine deiminase and urease. Arginase and argininosuccinate lyase were found in all species. Citrulline hydrolase was also found in all but the 2 strains carrying endosymbiotes C. deanei and C. oncopelti. On the other hand, ornithine carbamoyltransferase was found only in these 2 strains. Arginine deiminase and urease were absent in all strains. The existence of a common enzymatic pattern for species of the genus Crithidia is thus reported.

Notes: SYNOPSIS. Five strains of trypanosomatids, Herpetomonas megaseliae, H. samuelpessoai, H. muscarum muscarum, H. muscarum ingenoplastis and a newly isolated Herpetomonas sp., were examined for the enzymes of arginine-ornithine metabolism. Ornithine carbamoyltransferase (E.C. 2.1.3.3) and argininosuccinate lyase (E.C. 4.3.2.1) were detected in cell extracts of H. megaseliae, H. samuelpessoai and H. muscarum muscarum but not of others. Both enzymes seemed repressible by arginine, which could account for their apparent absence in H. muscarum ingenoplastis and Herpetomonas sp., which grow in a complex, arginine-rich medium. Additionally, arginine deiminase (E.C. 3.5.3.6) and citrulline hydrolase were detected in cell extracts of the 5 strains examined. This latter enzyme, previously described only in Tetrahymena, effects the single-step hydrolysis of citrulline into ammonia, ornithine and CO2. Arginase (E.C. 3.5.3.1) and urease (E.C. 3.5.1.5) were not found in any of the strains examined. Some of the physicochemical characteristics of the enzymes encountered are described.

Notes: SYNOPSIS. Phenol is the major organic constituent of coal-conversion scrub water and is therefore a potential environmental contaminant. After Tetrahymena pyriformis strain GL-C, syngen 1 was exposed to phenol, its behavior, cytology, respiration, and growth rates were examined. Concentrations ≥ 75 mg/liter alter cell motility, shape, and contractile vacuole activity. O2 uptake was abruptly reduced within 3 min of exposure to phenol in concentrations as low as 10 mg/liter. Concomitantly there was an increase in the electron density of the mitochondrial matrix. Recovery to normal rates of O2 consumption was paralleled by a return to normal matrix density. Alterations of mucocysts, pellicle, and glycogen were also observed. The length of lag phase growth curves increased generally in proportion to concentration of toxicant. Phenol, however, did not affect the rate of cell multiplication during the exponential growth phase. The potential use of this system to examine the effects of other possible organic pollutants is discussed.

Notes: SYNOPSIS. Sporulated oocysts of Eimeria nieschulzi Dieben, a rat coccidium, were exposed for 1 hr to Cobalt-60 γ-radiation (15, 30. or 60 k-rads), to heat (35, 40, or 45 C). or to both concurrently (15, 30, or 60 k-rads at 35 C) to compare the excystation capabilities of treated vs nontreated parasites. Intact, treated oocysts appeared structurally unaltered when viewed with the light microscope. Excystation of sporozoites occurred in all treated groups when their sporocysts were exposed to a trypsin-sodium taurocholate (TST) fluid, but after 150 min in TST the excystation rate was significantly lower than in non-treated sporocysts. Sporozoites which excysted from treated sporocysts were abnormal both in the excystation process and in their form and movement once outside the sporocyst.

Notes: SYNOPSIS. Mitochondria were isolated from Euglena gracilis strain Z by pressure-breakage of the cells and sucrose-cushion centrifugation. Multiple peaks (2-4) were observed in the rate of phosphorylation with Mg-ADP-phosphate concentration curves. The phosphorylative and oxidative activities were highest with NADH as the substrate, moderate with succinate, and lowest with glutamate. Inhibition of phosphorylation with 2,4-dinitrophenol and carbonyl cyanide, m-chlorophenylhydrazone gave sigmoidal concentration curves, with the extent of inhibition by DNP depending on the substrate used. Inhibition of phosphorylation by valinomycin, atractyloside, or carboxyatractyloside was only ∼ 60%. Oligomycin inhibited phosphorylation in 2 phases at low and high concentrations; it inhibited Mg-ATPase in a sigmoidal fashion. Both phosphorylation and oxidation had discontinuities in Arrhenius plots at 34 C and 18 C.The relative Mg2+-dependent nucleoside triphosphatase activity was: 1 for ATP and GTP, 0.6 for ITP, 0.15 for CTP and and UTP; with Ca2+ in place of Mg2+ this activity was 0.35. Both DNP and CCCP stimulated the Mg-ATPase 50-200%. The optimal pH for the stimulation was ∼ 7 regardless of the uncoupler used, and ∼ 8 without the uncouplers.The few differences observed between mitochondria from Euglena and those from other sources are probably due to the fragmentation of the reticular mitochondrial structure during isolation and not to unique characteristics of these mitochondria.

Notes: Book reviewed in this article:Jennings, D. H., Lee, D. L., eds. 1975. Symbiosis (Symposia of the Society for Experimental Biology Number XXIX).

Notes: SYNOPSIS The membranes, epiplasm, and fiber systems are described in the somatic cortex of Glaucoma chattoni strain HZ-1. Kinetodesmal fibers, postciliary and transverse microtubular ribbons, basal microtubules, transverse fibers and transverse accessory material are associated with kinetosomes. Longitudinal microtubular ribbons and mitochondria occur interkinetally. In the buccal cortex, the membranes, epiplasm and fibers of the 3 membranelles, the paroral kinety, the ribbed wall, and the cytostome are described. Comparisons between G. chattoni and other ciliates reveal ultrastructural differences of possible systematic significance. In the somatic cortex of this and other tetrahymenines. Iongitudinal microtubular ribbons and basal microtubules occur concurrently. In the buccal cortex, alveoli are absent in tetrahymenine membranelles. A table is presented of the fiber systems associated with single somatic kinetosomes of various ciliates whose cortical ultrastructure has been studied to date.

Notes: SYNOPSIS The fine structure of sporogonic stages of Nosema parkeri Krinsky, a microsporidan from the argasid tick, Ornithodoros parkeri Cooley, is described. Developmental changes in the spore coat and cytoplasmic organelles are discussed. As a sporoblast transforms into a spore, the organelles become more compact and the membranes surrounding them appear to become more taut. It is suggested that the polaroplast complex is involved in fluid transport during development of the spore. Organelles in the mature spore include 2 contiguous nuclei enveloped in a lattice containing ribosome-like particles, a polaroplast complex composed of laminar and saccular regions, and a coiled tubular polar filament attached to a polar sac. Sporogonic stages do not appear to have mitochondria, Golgi apparatus, or a posterior vacuole. The fine structure of the spore of N. parkeri is very similar to that of species of Nosema found in insects, crustaceans, and trematodes.

Notes: SYNOPSIS Doublet Paramecium tetraurelia contain either a single macronucleus which is substantially larger than that in a singlet cell, or 2 smaller macronuclei. Doublets have approximately twice the DNA content and twice the total protein content of singlets. The cell cycle of doublets is 164% as long as that of singlets, but the relative position of the macronuclear DNA synthesis period within the cell cycle is the same as in singlets. The DNA content of doublets is regulated so that differences in the number of macronuclei do not produce corresponding changes in DNA content; bimacronucleate doublets have only 27% more DNA than unimacronucleate doublets.

Notes: SYNOPSIS Triplet conjugants of Paramecium caudatum which appeared naturally in mating mixtures and those of Paramecium multimicronucleatum which were produced by conjugation-inducing chemicals were isolated. Triplet conjugants lasting for more than 3 h were stained to examine macronuclear events. In P. caudatum, only 2 triplets among 182 (1%) contained macronuclear fragmentation in all 3 members. The most frequently occurring triplets (79%) were those producing 1 cell without and 2 cells with macronuclear fragments. There were also triplets (17%) producing 1 cell with, and 2 without macronuclear fragments, and some (3%) with 3 cells that contained no fragments. The length of persistence of the triplet was not responsible for the occurrence of macronuclear fragmentation in the 3rd cell of the triplet. In P. multimicronucleatum, the same 4 classes of triplets occurred, but the most frequently occurring class was that consisting of 3 cells (91%) with macronuclear fragments. Induction of nearly 100% of triplets with 3 such cells was possible by isolating the triplets' from a culture which was treated chemically at about 24 h after the last feeding. Treatment with chemicals in starved cultures resulted in triplets with incompletely fragmented or nonfragmented macronuclei. Further, in P. multimicronucleatum, chemicallyinduced triplets involving only holdfast pairs to which the 3rd cells were uniting often produced 3 cells with fragmented macronuclei.

Notes: SYNOPSIS Observations were made on the ultrastructure of a species of Vorticella containing endosymbiotic Chlorella. The Vorticella, which were collected from nature, bore conspicuous tubercles of irregular size and distribution on the pellicle. Each endosymbiotic algal cell was located in a separate vacuole and possessed a cell wall and cup-shaped chloroplast with a large pyrenoid. The pyrenoid was bisected by thylakoids and surrounded by starch plates. No dividing or degenerating algal cells were observed.

Notes: SYNOPSIS Euglena gracilis strain Z, at a concentration of 106 cells/ml and in containers of ∽ 0.1-mm thickness, spontaneously forms dynamic ring patterns in the dark. These patterns are modified differentially by illumination with red and with blue light. The red light effect is abolished by treatment with an inhibitor of photosynthesis. Pattern formation is apparently the result of chemophobic responses to oxygen dissolved in the medium. Euglena can respond to both negative and positive concentration gradients, depending upon the absolute magnitude of oxygen concentration. The photo- and chemosensory transduction systems of Euglena interact at a stage which precedes the overt expression of motor responses.

Notes: SYNOPSIS The pattern of chloroplast development was followed in Euglena gracilis strain Z greening in media with a variety of fixed carbon and nitrogen sources. The greening pattern of cells grown in inorganic medium with added ethanol or glucose involves an inhibition of chloroplast development when compared to that of cells grown in inorganic medium alone. Several nitrogen sources were tested to ascertain their effectiveness in relieving the inhibition of chloroplast development by glucose. Of those, only 0.05% (w/v) (NH4)2 SO4 accelerated the recovery from the inhibition after most of the glucose had been removed from the medium by the cells. The other nitrogen sources tested were not effective. An inhibition of chloroplast development, similar to that observed in cells greening in the presence of glucose, was seen in cells greening in an ethanol-containing medium. These cells, however, had a different response upon the addition of 0.05% (NH4)2 SO4. They appeared to recover from the inhibition of chloroplast development, even before the ethanol was removed from the medium by the cells. A slight enhancement of chloroplast development was noted in cells greening in an inorganic medium with glycine or serine. Other amino acids tested had little or no effect.

Notes: Book reviewed in this article:Stanier, R. Y., Adelberg, E. A. & Ingraham, J. L. 1975. The Microbial World, 4th ed.