bluuebunny/crossref_metadata_2025 huggingface dataset:
The Permanence of the Infraciliature in Suctoria: An Electronmicroscopic Study of Pattern Formation in Tokophrya infusionum*
Authors: MILLECCHIA L. L. , RUDZINSKA M. A.
Published: May 2007

SYNOPSIS. The adult Tokophrya infusionum does not possess cilia, but has 20–30 barren basal bodies arranged in 6 short rows adjacent to the contractile vacuole pore. During reproduction, which is by internal budding, the contractile vacuole sinks into the parent along with the invaginating membranes that form the embryo and the wall of the brood pouch. The 6 rows of basal bodies radiate away from the pore and elongate to form 5 long ciliary rows, that encircle the anterior half of the embryo, and 1 short row at the posterior end. The contractile vacuole pore, along with several barren basal bodies, remains in the parent when the embryo is completed. The pore rises to the surface when the embryo is born. New basal bodies are then formed in the parent to replace those which were incorporated into the embryo, and formation of another embryo may begin. The cilia of the embryo are partially resorbed 10 min after the start of metamorphosis, with depolymerization of the ciliary microtubules. Later, the cilia and most of the basal bodies disappear completely, except for a group of barren basal bodies near the embryo's contractile vacuole pore, which form 6 rows and serve as an anlage for the basal bodies and cilia that arise during embryogenesis. There is, therefore, an organized infraciliature in Suctoria throughout their life cycle, and a distinct continuity of basal bodies across the generations.
Do Protoplasmic Connections Function in the Phototactic Coordination of the Volvox Colony During Light Stimulation?*
Authors: HIATT JILL D. FABRICANT , HAND WILLIAM G.
Published: May 2007

SYNOPSIS. The flagellar behavior of the colonial flagellates Volvox carteri Stein and Volvox perglobator Powers was examined by placing 1.01 μm polystyrene particles in solution with swimming colonies, and photographing these particle movements. When directional light stimulation was administered to individual colonies, a cessation of flagellar activity occurred in the anterior cells of the stimulated side in both species. Since Volvox perglobator possesses prominent intercellular connections and Volvox carteri does not, the results of these experiments suggest that the connections linking colony members in some species do not function in the coordination of flagellar activity associated with light orientation behavior.
Leishmania in the Chick Embryo. I. Multiplication of Amastigotes of L. donovani in the Liver*
Authors: HOLBROOK THOMAS W. , STAUBER LESLIE A.
Published: May 2007

SYNOPSIS. On the 14th day of incubation chick embryos were inoculated intravenously with approximately 4 × 104 amastigotes of Leishmania donovani in ground, infected hamster spleen. Embryos were then incubated at 28, 33, or 37 C. At 1 hr and at 2, 4, and 6 days postinfection embryos were killed, and parasite burdens in the liver and spleen estimated by the method of Stauber. The spleen played a relatively minor role in clearance of amastigotes from the bloodstream and parasites did not survive beyond the 2nd day. In each experiment ∼20% of the injected amastigotes were found in the liver after 1 hr. Numbers of amastigotes declined in embryos incubated at 37 C and were not observed later than 2 days postinfection. At 33 C the amastigotes multiplied at a rapid rate, and at 28 C they not only multiplied but, in some instances, transformed to the promastigote form.
Enzyme Activity Pattern and Mitochondrio‐cytoplasmic Relations in Protozoa. Comparative Study of Tetrahymena pyriformis, Allogromia laticollaris, and Labyrinthula coenocystis
Authors: HOFER HANS WERNER , PETTE DIRK , SCHWAB‐STEY HILTRUD , SCHWAB DIETER
Published: May 2007

SYNOPSIS. Enzyme activity patterns were determined in Tetrahymena pyriformis, Allogromia laticollaris, and Labyrinthula coenocystis. The activities of enzymes belonging to certain metabolic pathways (glycolysis, fatty acid oxidation, tricarboxylic acid cycle) had constant proportions in each species, whereas their absolute levels differed. The activities of intramitochondrial enzymes were compared with the mitochondrial to total cytoplasmic volume ratio. Despite the very different fine structure of the mitochondria in the 3 protozoa, there was good correlation between the activities of citric acid cycle enzymes and the mitochondrial volume.
Comparaison morphologique de 4 souches d'Acanthamoeba du groupe astronyxis‐comandoni
Authors: PUSSARD M.
Published: May 2007

RESUME

Les trophozoïtes, les noyaux mitotiques et les kystes de 3 souches d'Acanthamoeba comandoni Pussard et d'l souche d'Acanthamoeba astronyxis Ray & Hayes ont été observés sur le vivant pour étudier les caractères morphologiques utilisés pour séparer les 2 espèces (Griffin & Sawyer, 1971).

Chez toutes les souches, la centrosphère est visible pendant l'intercinèse comme pendant la mitose. Acanthamoeba astronyxis se distingue des autres souches essentiellement par la forme de la figure nucléaire à la prométaphase. Les caractères de la paroi du kyste ne permettent pas d'opposer nettement Acanthamoeba astronyxis aux autres souches.

Les dimensions des trophozoïtes et le diamètre des kystes sont trop variables pour être utilisables en taxonomie. Chez toutes les souches existe une corrélation positive entre la taille du kyste et le nombre des bras de l'enveloppe interne.

SYNOPSIS

Observations of living trophozoites, mitotic nuclei, and cysts of 3 strains of Acanthamoeba comandoni Pussard and of 1 strain of Acanthamoeba astronyxis Ray & Hayes were made to study the morphologic characters utilized by Griffin & Sawyer (1971) for separating the 2 species. In all 4 strains the centrosphere is visible in the interphase just as during mitosis. A. astronyxis differs from the other strains essentially in the shape of the nuclear pattern in prometaphase. The characteristics of the cyst wall do not permit clear differentiation between the 2 species. Size of the trophozoites and diameter of the cysts are too variable to be utilized for taxonomic purposes. In all 4 strains there is a positive correlation between size of the cyst and the number of rays of its internal layer (endocyst).
Protosporangium: a New Genus of Protostelids*
Authors: OLIVE LINDSAY S. , STOIANOVICH CARMEN
Published: May 2007

SYNOPSIS

Protosporangium is described as a new genus of the mycetozoan order Protosteliida, with 3 new species: P. bisporum, P. fragile, and P. articulatum. The genus is characterized by minute, mostly 2‐4‐spored sporangia borne on long, slender, flexuous stalks. The spores produce flagellate cells (typically 8 per sporangium) during germination. The trophic stage is holozoic and uninucleate to plurinucleate but never reticulate. Plurinucleate protoplasts segment into uninucleate (sometimes binucleate) prespore cells that culminate to form sporocarps in the manner characteristic of protostelids.
Die Infraciliatur von Marituja pelagica Gajewskaja, 1928*
Authors: WILBERT NORBERT
Published: May 2007

SYNOPSIS

The ciliate Marituja pelagica Gajewskaja, 1928 was described originally from Lake Baikal. Recently this organism was found in the plankton of a eutrophic pond in the area of Bonn. Studies of structure of living ciliates and of silver‐stained preparations aided in the solution of hitherto existing taxonomic problems with regard to M. pelagica and led to its placement in the suborder Peniculina.
Ultrastructural Localization of Acid Phosphatase in Feeding Tokophrya infusionum*
Authors: RUDZINSKA MARIA A.
Published: May 2007

SYNOPSIS

A combined cytochemical and electronmicroscopic study of feeding Tokophrya revealed that it has 2 sources of acid phosphatase. One is from the prey, Tetrahymena, supplying newly formed food vacuoles with large amounts of enzyme. The other source is in Tokophrya itself, the enzyme being found in small vesicles, small dense elongate bodies surrounded by a membrane, or in residue vacuoles. It seems that the 2 former small structures contain insignificantly small amounts of phosphatase; however, large deposits of lead phosphate are present in residue vacuoles, former food vacuoles. Since Tokophrya has no cytopyge these vacuoles are not excreted. On the contrary, when feeding is resumed, they merge with food vacuoles, presumably supplying them with acid phosphatase. Whether this enzyme ultimately is derived from the prey Tetrahymena and persists undegraded in the residue vacuoles, or whether it is synthesized by Tokophrya cannot be determined from present work.
Experimental Histomoniasis in the Guinea Fowl, Numida meleagris*
Authors: CHUTE ANNE M. , LUND EVERETT E.
Published: May 2007

SYNOPSIS

Guinea fowl were inoculated rectally with Histomonas meleagridis to produce histomoniasis. The birds were infected readily by this unnatural route. Severe cecal involvement was frequent and long‐lasting but liver lesions and death were rare. Turkeys given the same inoculum had high levels of liver involvement and mortality. Guinea fowl responded much less severely to infection with H. meleagridis when infected by a natural route (ingestion of a vector) rather than by rectal inoculation. Thus, naturally acquired infections with H. meleagridis appear to be of small consequence in the guinea fowl.
Immunity to Babesia bigemina in Experimentally Infected Cattle
Authors: LÖHR K.‐F.
Published: May 2007

SYNOPSIS

Two groups of 5 and 6 Babesia bigemina“vaccine donor” animals of which 8 had been splenectomized were challenged 6 and 12 months respectively after they had lost their carrier state. All animals of the former, and 3 of the latter group survived; the remaining 3 animals succumbed to the challenge and died. It was concluded that premunity to B. bigemina is followed by sterile immunity which lasts for at least 6 months. Thereafter it fades gradually with time, depending on the immune response of the host, but can last for at least 12 months.

Six splenectomized animals, which had lost their infectivity after treatment of their initial B. bigemina parasitemia at the rapidly rising phase with 1 mg/kg Berenil, died on challenge. It was concluded that a minimum period of contact between host and parasite is required for the acquisition of immunity to B. bigemina.

Capillary tube agglutination titers were generally higher in the protected than in the unprotected animals. They remained fairly high for a long period after animals had lost their carrier state, which indicated the sensitivity of the CA test but rendered it unreliable for the detection of carrier animals.
The Molecular Biology of Euglena gracilis. VIII. Glycitols and Monosaccharides
Authors: KEMPNER E. S. , MILLER J. H.
Published: May 2007

SYNOPSIS

Mannitol is identified as the major component of the small molecule pool of Euglena gracilis strain Z. Smaller amounts of glycerol also are found. Results of tracer studies and enzymic measurements indicate that both major mannitol pathways found in bacteria are present in Euglena.
Synthesis of RNA, Protein, Cellulose, and Mucopolysaccharide and Changes in the Chemical Composition of Hartmannella culbertsoni During Encystment under Axenic Conditions*
Authors: RAIZADA M. K. , MURTI C. R. KRISHNA
Published: May 2007

SYNOPSIS

Hartmannella culbertsoni trophozoites are transformed into viable cysts on exposure to a non‐nutrient agar medium containing 15 mM MgCl2 and 20 mM taurine. Amebae differentiating in this encystment medium incorporate more uracil‐2‐14C into RNA and more leucine‐1‐14C or valine‐1‐14C into proteins than controls. Encysting organisms incorporate significantly more glucose‐U‐14C into cellulose and glucosamine‐1‐14C into mucopolysaccharides. Incorporation of glucose‐U‐14C into cellulose and of glucosamine‐1‐14C into mucopolysaccharides are inhibited by actinomycin D or cycloheximide.
Malaria Parasites of the “Borriguerro'’Lizard, Ameiva ameiva (Sauria: Teiidae) in Panama*
Authors: TELFORD SAM R.
Published: May 2007

SYNOPSIS. The teiid lizard Ameiva ameiva praesignis in Panama is parasitized by 2 species of Plasmodium: P. cnemidophori Carini and P. diminutivum sp. n. The Panamanian strain of P. cnemidophori has thick macrogametocytes which are larger than the oval microgametocytes, and schizonts which contain 42–119 nuclei. P. diminutivum is characterized by round to oval gametocytes which are usually smaller than the host cell nucleus; fan‐shaped schizonts with 4–6 nuclei; and prominently vacuolated young stages, with a thick band of chromatin along the periphery of the vacuole.
The Fine Structure of the Centriolar Apparatus and Associated Structures in the Flagellates Deltotrichonympha and Koruga. I. Interphase
Authors: TAMM SIGNHILD , TAMM SIDNEY L.
Published: May 2007

SYNOPSIS. An electronmicroscopic study was made of the centriolar apparatus in the rostrum of Deltotrichonympha operculata and Koruga bonita, 2 closely related hypermastigote flagellates from the Australian termite, Mastotermes darwiniensis. In interphase flagellates, the centriolar apparatus consists of 2 similar parts with a mutually perpendicular orientation. Each part contains a large, club‐shaped centriolar body consisting of fibrillar and granular material, without recognizable internal symmetry or microtubules. The anterior centriolar body extends from the inner rostral wall, which is structurally related to the fibrous wall surrounding the posterior centriolar body. The 2 centriolar bodies are joined by connecting branches, which meet at 3 barren kinetosome‐like structures located inside the rostrum. Thus, an interphase flagellate has 2 centriolar bodies oriented at a 90° angle to each other, like a pair of typical centrioles in an interphase metazoan cell.
The Resorption of Cilia in Cyathodinium piriforme*
Authors: PAULIN JEROME J.
Published: May 2007

SYNOPSIS. The fine structure of the cilium, kinetosome, kinetodesmal fiber, and basal microtubules has been described in Cyathodinium piriforme. The ciliary axoneme is encased in an electron‐dense jacket termed the axonemal jacket. This jacket surrounds the axoneme and is found midway between the axoneme and the ciliary membrane when viewed in cross section. Before division or reorganization the cilia are withdrawn into the cell. Intact cilia surrounded by their jackets are found in the cytoplasm during the early phases of retraction. Degradation of the axonemal microtubules precedes the dissolution of the axonemal jacket. Profiles of the jackets are observed after the microtubules have been resorbed. The cilia appear to detach from the kinetosomes. Barren kinetosomes are seen below the cell surface frequently with kinetodesmal fibers still attached. Whether all or some of these barren kinetosomes contribute to the formation of the new ciliary anlage cannot be ascertained.
Sensitivity of Paramecium Thermotaxis to Temperature Change
Authors: TAWADA K. , MIYAMOTO H.
Published: May 2007

SYNOPSIS. The relationship to swimming velocity of the critical temperature gradient necessary for inducing thermotaxis in Paramecium caudatum was analyzed at various temperatures and viscosities. Since the critical temperature gradient was linearly proportional to the inverse of the swimming velocity, it is concluded that P. caudatum detects temperature changes by locomotion through space and thus exhibits thermotaxis, provided the rate of change is > 0.055 C/sec. The swimming velocity jump was observed when the ciliates were subjected to a stepwise temperature change toward an optimum with a rate > 0.05 C/sec; the jump was not observed, however, when they were subjected to a change toward an unpreferred temperature with the same rate. Hence, thermotaxis can be explained partly by the swimming velocity jump brought about when the cells are swimming toward an optimum temperature in a spatial gradient. It is suggested that thermotaxis might be a direct manifestation of the dynamic properties of membrane as a receptor.
In vitro Development of First‐Generation Schizonts of Eimeria canadensis (Bruce, 1921)*†
Authors: MÜLLER BODO E. G. , VOS ALBERTUS J. DE , HAMMOND DATUS M.
Published: May 2007

SYNOPSIS. In vitro development of Eimeria canadensis from cattle was studied in monolayer cultures of various bovine cell lines grown on coverslips in Leighton tubes. Excysted sporozoites were used for inoculation of the cell cultures. Sporozoites entered the host cells within a few minutes, but apart from a reduction in the number of refractile bodies, changed little in appearance during the first 9 days. Beginning at 91/2 days postinoculation, sporozoites developed into sporozoite‐shaped schizonts or, less frequently, transformed into trophozoites. Sporozoite‐shaped schizonts with as many as 8 nuclei were observed transforming into spheroid schizonts. At 111/2 days, intermediate schizonts had a characteristic single mass of refractile granules and 60–80 nuclei. Deep invaginations, which resulted in the formation of several blastophores, usually occurred when schizonts had about 100 nuclei. Merozoites were formed as a result of radial outgrowth from the surface of spheroid schizonts as well as of blastophores. Mature merozoites were seen 1st after 13 days.
Sublethal Cytotoxic Effects of Mercuric Chloride on the Ciliate Tetrahymena pyriformis*
Authors: TINGLE LESLIE E. , PAVLAT WILLIAM A. , CAMERON IVAN L.
Published: May 2007

SYNOPSIS. The behavior and ultrastructure of Tetrahymena pyriformis was assessed after exposure to dosages of 8 and 16% of the lethal concentration of HgCl2 (TLm 96 hr). The lower dosage caused no abnormal changes in cell motility, activity of the water explusion vesicles, or cell shape; the higher dosage caused deleterious changes in these parameters. The higher sublethal HgCl2 concentration (0.50 mg/liter) elicited damage of several cell structures. This damage persisted and accumulated with time up to 24 hr. At the lower HgCl2 dosage (0.25 mg liter) there were extensive changes after 1‐hr exposure involving primarily mitochondria; however, all major changes were repaired after 24 hr of constant exposure to the HgCl2, indicating adaptation to the toxicant. Based solely on cytotoxic evidence an attempt is made to apply the findings defining what constitutes a “safe'’concentration of HgCl2 in the cell's environment.
Eigenschaften des Elektronentransportsystems von Mitochondrien des Protisten Acanthamoeba castellanii Neff. II. Reinigung und Eigenschaften der NADH‐Akzeptor‐Oxydoreduktase des Elektronentransportsystems
Authors: FOUQUET H.
Published: May 2007

ZUSAMMENFASSUNG. Es wird die Reinigung einer mitochondrialen NADH‐Akzeptor‐Oxydoreduktase (EC. 1.6.99.3) über folgende Stufen beschrieben: fraktionierte Ammonsulfatfällung, Chromatographie an DEAE‐Cellulose und Molekularsiebchromatographie an Sephadex G 100. Das gewonnene Enzympräparat erwies sich als elektrophoretisch rein. Die Michaeliskonstante für NADH als einziges Substrat liegt bei 6,9 × 10−5 M NADH. Ein ebenfalls isoliertes extramitochondriales Enzym underscheidet sich vom intramitochondrialen in drei voneinander unabhängigen Eigenschaften: Substratspezifität, elektrophoretiche Mobilität, Molekulargewicht. Das isolierte intramitochondriale Enzym verhält sich gegenüber Atmungsketteninhibitoren ähnlich wie isolierte Mitochondrien.

SYNOPSIS. Mitochondrial NADH reductase (EC. 1.6.99.3) was isolated from Acanthamoeba castellanii by the following steps: fractionation by (NH4)2SO4 precipitation, DEAE‐cellulose chromatography, and chromatography on Sephadex G 100 columns. Purity of the enzyme preparation was demonstrated by electrophoresis. With NADH as the sole substrate, the Km= 6.9 × 10−5 M NADH. Extramitochondrial enzyme, also isolated from the ameba, differed from the mitochondrial one in substrate specificity, electrophoretic mobility, and molecular weight. The mitochondrial NADH reductase and isolated mitochondria were affected in the same way by respiratory chain inhibtors.
Eimeria diminuta sp. n. from the Ceylon Jungle Fowl, Callus lafayettei*
Authors: FERNANDO M. A. , REMMLER O.
Published: May 2007

SYNOPSIS. Eimeria diminuta sp. n. is described from the Ceylon jungle fowl Gallus lafayettei. Its sporulated oocysts are 16.5 (16–17.5) × 14.5 (13.5 × 15.5) μm. The species produces patent infections in domestic fowl.
Observations on the Proboscis‐Cytopharynx Complex and Flagella of Rhynchomonas metabolita Pshenin, 1964 (Zoomastigophorea: Bodonidae)*
Authors: BURZELL LINDEN A.
Published: May 2007

SYNOPSIS. The description of Rhynchomonas metabolita is amended on the basis of new electronmicroscopic and other evidence. The proboscis of R. metabolita is not derived from the anterior flagellum, but rather is an outward extension of the cytopharynx. Food organisms are taken up near the distal tip of the proboscis and pass through a membrane‐limited lumen continuous with the permanent cytopharynx. The cytopharynx‐proboscis lumen is surrounded by overlapping rows of microtubules running parallel to the long axis of the lumen; these may be involved in the accommodation of food particles that are larger than the resting diameter of the lumen.

R. metabolita has 2 emergent flagella, the previously described trailing flagellum and a hitherto unreported shorter anterior flagellum that is closely associated with the proboscis; the anterior flagellum and proboscis normally beat synchronously. A paraxial rod is present in both flagella. Rhynchobodo Lackey, 1940 is probably a synonym of Rhynchomonas.
Haematozoa in Domestic Chickens and Guinea Fowl in Tanzania and Transmission of Leucocytozoon neavei and Leucocytozoon schoutedeni
Authors: FALLIS A. M. , JACOBSON R. L. , RAYBOULD† J. N.
Published: May 2007

SYNOPSIS. Leucocytozoon neavei and Leucocytozoon caulleryi were found in guinea fowl in Tanzania and Leucocytozoon schoutedeni in chickens. The minimum time required for sporogony of L. neavei at approximately 20 C was ∼7 days in Simulium adersi and Simulium nyasalandicum. Gametocytes of L. neavei, which appeared mature, were seen in the peripheral blood of guinea fowl chicks 14 days after experimenal inoculation with sporozoites from S. adersi or S. nyasalandicum. Sporogony of L. schoutedeni was followed in “Simulium impukane,” S. adersi, Simulium vorax and S. nyasalandicum. Oocysts were ∼12 μm in diameter. Sporogony of some individuals was completed in 6–7 days at 20 C. Each oocyst produced ∼50–60 sporozoites. Gametocytes were detected in the peripheral blood of a chicken 10–14 days after experimental inoculation with sporozoites of L. schoutedeni from S. adersi and “S. impukane.”
Some Qualitative Aspects of Spleen Cell Transfer Studies on Plasmodium berghei‐Infected Rats*
Authors: CABRERA EDELBERTO J. , ALGER NELDA E. , SILVERMAN PAUL H.
Published: May 2007

SYNOPSIS. Adoptive immunity to Plasmodium berghei was transferred by intraperitoneal injections into rats, never before exposed to this parasite, of either 2 × 107 or 2 × 108, but not of 2 × 106, spleen cells from syngenic rats which had recovered from a primary P. berghei infection. When the spleen cells from the latter animals were kept at 47 C for 45 min they remained alive, but no longer were able to transfer protection. The capacity to transfer adoptive immunity was not found in spleen cells from adult rats capable of age immunity. On the other hand, this capacity was found in spleen cells from rats that had suffered a very transient parasitemia (> 1% peak parasitemia).
ATPase Activity in Isolated Flagella from Euglena gracilis
Authors: PICCINNI ESTER , ALBERGONI VINCENZO
Published: May 2007

SYNOPSIS. The ATPase activity of isolated flagella was studied in Euglena gracilis strain Z in the presence of Mg++ or Ca++. With Mg++, the optimum activity was at pH 7 and with Ca++, at pH 9. The Km values were respectively 6.6 × 10−4 and 3.6 × 10−4. Activity was influenced also by temperature and ionic strength. Results with inhibitors of membrane ATPase suggest the presence of a specific contractile system in the flagella. Our results are compatible with a multicomponent enzymic system containing 2 active ATPases.
Nuttallia balearicae sp. n., an Avian Piroplasm from Crowned Cranes (Balearica spp.)
Authors: PEIRCE M. A.
Published: May 2007

SYNOPSIS

An avian piroplasm, Nuttallia balearicae sp. n., is described from captive Balearica p. pavonina and B. p. gibbericeps. Other avian piroplasms and their validity and taxonomic status are discussed. The possible route of transmission of these parasites is also considered.
Fine Structure and Life Cycle of Lankesteria clarki sp. n. (Sporozoa: Eugregarinida) Parasitic in the Mosquito Aedes sierrensis (Ludlow)
Authors: SANDERS R. D. , POINAR G. O.
Published: May 2007

SYNOPSIS

Lankesteria clarki sp. n. from the treehole mosquito, Aedes sierrensis (Ludlow) in California, is described. This species can be separated from the closely related ones, L. culicis (Ross) and L. barretti Vávra, by the totally intracellular nature of the trophozoite, the shape of the gamont, the position of the gamont nucleus and the structure and position of the residual body in the spore. Morphologic and ultrastructural investigations of gametogenesis and sporogony were conducted and the host relationship discussed. Lankesteria clarki was found in mosquitoes collected from all treeholes examined near Novato in Marin County, California and an examination of over 6,000 larvae of A. sierrensis showed an infection rate of 27.5%. The parasite is capable of destroying the midgut epithelial cells during its trophic stage and Malpighian tubule cells during gametogenesis and sporogony.
Fine Structure of Gametogony and Oocyst Formation in Sarcocystis sp. in Cell Culture
Authors: VETTERLING JOHN M. , PACHECO NANCY D. , FAYER RONALD
Published: May 2007

SYNOPSIS

Fine structure of gametocytes and oocyst formation of Sarcocystis sp. from Quiscalus quiscula Linnaeus grown in cultured embryonic bovine kidney cells was studied. Microgametocytes measured up to ∼5 μm diameter. During nuclear division of the microgametocyte, dense plaques were found adjacent to the nucleus just beneath the pellicle; occasionally microtubules were present within these plaques. These microtubules subsequently formed 2 basal bodies with a bundle of 4 microtubules between them. Microgametocytes also contained numerous mitochondria, micropores, granules, vacuoles, and free ribosomes. Each microgamete was covered by a single membrane and consisted of 2 basal bodies, 2 flagella, a bundle of 4 microtubules, a perforatorium, a mitochondrion, and a long dense nucleus which extended anteriorly and posteriorly beyond the mitochondrion. The bundle of 4 microtubules is thought to be the rudiment of a 3rd flagellum. Macrogametes were covered by a double membrane pellicle, and contained a large nucleus (∼2.5 μm), vacuoles, and a dilated nuclear envelope connected with the rough endoplasmic reticulum (ER). In young macrogametes (∼4 μm), the ER was arranged in concentric rows in the cortical region, and several sizes of dense granules were found in the cytoplasm. However, in later stages (∼8 μm) the ER was irregularly arranged and was dilated with numerous cisternae; only large dark granules remained and a few scattered polysaccharide granules were found. No Golgi apparatus or micropores were observed. After the disappearance of dark granules 5 concentric membranes appeared. Four of these fused to form an oocyst wall composed of a dense outer layer (∼66 nm thick) and a thin inner layer (∼7 nm). The 5th or innermost membrane surrounded the cytoplasmic mass which was covered by a 2‐layered pellicle and contained a nucleus, small amounts of ER, large vacuoles, and mitochondria. The sexual stages described greatly resemble those of Eimeria and Toxoplasma.
Influence of Culture pH on Chloroplast Structure in Euglena gracilis
Authors: COOK J. R. , LI THERESA C. C.
Published: May 2007

SYNOPSIS

Chloroplasts of Euglena gracilis grown with phototrophic nutrition at pH 3.0 were compact, while those in cells grown at pH 8.1 were swollen with widely separated lamellae.
The Cell Cycle and Induced Amitosis in Acanthamoeba*
Authors: BAND R. NEAL , MOHRLOK SHARON
Published: May 2007

SYNOPSIS

The small soil ameba, Acanthamoeba castellanii strain HR, with a mean generation time of 18 hr in axenic culture, requires 24 min for nuclear mitosis. This is followed immediately by nuclear DNA synthesis that is initiated in late telophase and lasts for 20 min.

Evidence is presented that amitosis can be induced in susceptible amebas only during a portion of the cell cycle.
The Mechanism of Acetate and Pyruvate Oxidation by Trypanosoma cruzi
Authors: DE BOISO JULIA F. , STOPPANI ANDRÉS O.M.
Published: May 2007

SYNOPSIS

The epimastigote or culture form of Trypanosoma cruzi oxidizes [3‐14C] pyruvate and [2‐14C] acetate to 14CO2 without an apparent increase in overall respiration. This oxidation takes place through the tricarboxylic acid cycle as shown by (a) the incorporation of substrate 14C into cycle intermediates; (b) the earlier liberation of acetate carboxyl carbon as CO2; and (c) the characteristic intramolecular distribution of pyruvate and acetate carbon atoms in the skeletal carbon of aspartic and glutamic acids. Upon oxidation of [3‐14C] pyruvate and [2‐14C] acetate, two of the products, alanine and glutamic acid, are found to account for more than 50% of incorporated 14C; labeling of alanine predominates with [3‐14C] pyruvate while labeling of glutamic acid predominates with [2‐14C] acetate. Using [1‐ or 6‐14C] glucose as substrate, the pattern of 14C distribution in soluble metabolites closely resembles that obtained with [3‐14C] pyruvate, in accordance with the joint operation of the Embden‐Meyerhof pathway and Krebs cycle. The cycle operation depends on electron transport through the mitochondrial respiratory chain, since antimycin A, at a relatively low concentration, inhibits the oxidation of [2‐14C] acetate to 14CO2, to the same extent as the parasite respiration. Though functional in T. cruzi epimastigotes, the oxidative role of the Krebs’ cycle is apparently limited by the absence of an efficient oxidative apparatus. The cycle operation does, however, constitute an important source of skeletal carbon for the biosynthesis of amino acids and can contribute to the process of glycogenesis.
The Stalk of the Suctorian Tokophrya infusionum: Histochemistry, Biochemistry, and Physiology
Authors: HASCALL GRETCHEN K.
Published: May 2007

SYNOPSIS

Tokophrya infusionum, a sessile suctorian with an external stalk and adhesive disc, has in its life cycle a ciliated, swimming embryo which metamorphoses into the adult form. The addition of NiCl2 to the medium induced metamorphosis immediately; however, other salts had no effect. Incomplete metamorphosis, without stalk formation, occurred if the organism began metamorphosis before its anterior (stalk‐forming) end touched a substrate.

The stalk was studied by histochemical and biochemical technics to determine its composition. The stalk stained with mercury‐bromphenol blue, and Alcian blue under a variety of conditions, but not with PAS. These results suggest that the stalk contains protein and sulfate groups, possibly in the form of a sulfated protein‐polysaccharide. The stalk was insoluble in several common laboratory reagents, but did dissolve in hot 6 N HCl, 2 N NaOH, and papain. It was evident from amino acid analysis of the stalk and of the whole organism that 15% of the total protein is located in the stalk.
Observations on Askenasia volvox (Claparède & Lachmann, 1859)
Authors: TAMAR HENRY
Published: May 2007

SYNOPSIS

Specimens of Askenasia volvox from southwestern Indiana have a variable body shape and a size range of 29 × 22 μ m to 42 × 27 μ m. The pectinelles, membranelles, and cirri each number 47–48, and respectively have a length of 8–10, 20, and 30 μ m. The pectinelles arise from ciliary rows consisting of ∼10 kinetosomes, and every membranelle originates from 2 adjacent rows of ∼14–17 kinetosomes. Different algae as well as Bodo and certain other protozoa are ingested. The macronucleus, micronucleus, the cytoplasm and its inclusions, trichites, the function of the contractile vacuole, and movements and behavior are described.
A Scanning Electron Microscope Study on Gregarina sp. from Udeopsylla nigra*
Authors: HELLER GERT , WEISE ROBERT W.
Published: May 2007

SYNOPSIS

Scanning electron microscope studies on Gregarina sp. from the cricket Udeopsylla nigra revealed that the epicytic folds of the younger gamonts are undulatory, whereas those of the older gamonts are relatively straight. The protomerite of the primite is conical with a mammiliform structure at the anterior tip, where the epicytic folds originate from a disc‐like structure. The protomerite of the satellite is flattened.
Efficacy of Monensin Against Bovine Coccidiosis in Young Holstein‐Friesian Calves*
Authors: FITZGERALD PAUL R. , MANSFIELD M. E.
Published: May 2007

SYNOPSIS

Monensin, an anticoccidial antibiotic, was incorporated into pelleted feed and given to 10‐week‐old Holstein‐Friesian calves at 0.25 mg/kg, 1.0 mg/kg, or 2.0 mg/kg of body weight. Inoculated calves were inoculated by drenching with 500,000 sporulated oocysts of Eimeria bovis. Other calves served as inoculated or uninoculated controls. Observations were recorded on oocyst discharge in the feces, clinical signs, weight gain, food consumption, hemoglobin, packed cell volume, total serum protein, sodium and potassium content of the serum, and differential white cell counts.

Calves in the inoculated control group developed severe infections, discharged large numbers of oocysts, developed clinical signs and 1 of 5 died. Uninoculated, untreated control calves were essentially free of coccidia. A few calves in the groups which received monensin developed light infections but none of them had clinical signs of coccidiosis. Calves which received the highest and the lowest dosages of monensin gained weight less rapidly than did the uninoculated controls or the animals which received monensin at 1.0 mg/kg of body weight. Inoculated control calves with severe infections had reduced food intake and a significant reduction in weight which was not regained during the experimental period.

The only other significant change in any of the parameters measured was a reduction in the total serum protein of inoculated, nonmedicated control calves. The level returned to normal 5 weeks after clinical signs first appeared.
Response of Fresh‐Water Protozoan Artificial Communities to Metals*
Authors: RUTHVEN JEANNE A. , CAIRNS JOHN
Published: May 2007

SYNOPSIS

An artificial fresh‐water protozoan community was subjected to different concentrations of Zn and Cu in a test system consisting of Plexiglas troughs through which pond water flowed continuously. Although the % survival of colonizing species exposed to Cu or Zn fluctuated greatly at each concentration, the range of toxicity for each compound allowed comparison of protozoa with other organisms with respect to resistance to heavy metal toxicity. Individual protozoan species also were exposed for 3 hr to Zn, Cu, Cr, phenol, Pb, Mn, Co, HNO3, acetic acid, Al, Sn, and HCl to derive time to death curves. Protozoa tested appeared to be more resistant than Daphnia to phenol, K2C2O7, and Cu; however, some species were more sensitive than Daphnia to Zn, nitric acid, and HCl. This suggests that the sensitivity of protozoa to toxicants may be either more or less than that of macroinvertebrates and that information does not suffice to predict sensitivity. Moreover, the relative sensitivity of protozoa to various toxicants will not always be the same, i.e. species X may be twice as tolerant to a toxicant as species Y but its relative sensitivity may be quite different for another toxicant.
Trypanosomatidae Isolated from Zelus leucogrammus (Perty, 1834) (Hemiptera, Reduviidae), with a Discussion on Flagellates of Insectivorous Bugs*
Authors: CARVALHO AURORA L. M. , DEANE MARIA P.
Published: May 2007

SYNOPSIS

The insectivorous bug Zelus leucogrammus (Perty, 1834) (Hemiptera, Reduviidae) was found to harbor several species of trypanosomatids of the genera Leptomonas, Crithidia, Herpetomonas and Blastocrithidia. However, laboratory bred nymphs given sterile food were infected only by Blastocrithidia, the other flagellates appearing in their intestinal tract when they were fed on other insects.

The Blastocrithidia was thought to belong to a single species and to be a parasite proper of Z. leucogrammus (and possibly other Hemiptera), producing luxuriant infections in the intestinal tract of the bugs captured in nature and spreading easily among isolated populations through cannibalism and ingestion of cysts; it was also abundant in the genital tract of gravid females but transovarian transmission was not proved. This Blastocrithidia experimentally infected Triatoma infestans and is very close to B. triatomae Cerisola, del Prado, Rohwedder and Bozzini, 1971.

The other trypanosomatids, never numerous in naturally infected Z. leucogrammus, are acquired by the bug from many different insects, chiefly Diptera, on which it was seen to feed. Herpetomonas muscarum and C. luciliae, the common trypanosomatids among several muscoid Diptera, were isolated both from flies and from the bugs fed on them.
Kudoa cerebralis sp. n. (Myxosporidea, Chloromyxidae) from the Striped Bass, Morone saxatilis (Walbaum)*
Authors: PAPERNA I. , ZWERNER D. E.
Published: May 2007

SYNOPSIS

Kudoa cerebralis sp. n. is described from connective tissue of the nervous system in the striped bass, Morone saxatilis (Walbaum), from the southern Chesapeake Bay area. This is the first time the genus Kudoa has been found in association with the nervous system. The polar view mean diameter of the spores was 7.0 μm and the polar capsule mean length was 3.7 μm.
Rumen Ciliate Fauna of Alaskan Moose (Alces americana), Musk‐Ox (Ovibos moschatus) and Dall Mountain Sheep (Ovis dalli)*
Authors: DEHORITY B. A.
Published: May 2007

SYNOPSIS

Total numbers, generic distribution and percentage species distribution were determined for the ciliate protozoa in rumen contents obtained from Alaskan moose (Alces americana), musk‐ox (Ovibos moschatus) and Dall mountain sheep (Ovis dalli). The musk‐ox has a fauna somewhat similar to that previously observed in reindeer and caribou. In contrast, only protozoa in the genus Entodinium were observed in moose, while Dall mountain sheep have a fauna unique among Alaskan ruminants studied to date. Other than Entodinium exiguum which was common to all animals, only 2 additional species of Entodinium, observed in the moose and musk‐ox, occurred in more than one animal species. Four new species of protozoa are described, Entodinium dalli sp.n., Entodinium constrictum sp.n. and Polyplastron alaskum sp.n. from the Dall mountain sheep and Entodinium alces sp.n. from moose.
Study of Dientamoeba fragilis Jepps & Dobell I. Electronmicroscopic Observations of the Binucleate Stages II. Taxonomic Position and Revision of the Genus*
Authors: CAMP RUSSELL R. , MATTERN CARL F. T. , HONIGBERG B. M.
Published: May 2007

SYNOPSIS

Light‐ and electronmicroscopic observations on Dientamoeba fragilis strain A (Bi) 1 dealing primarily with the binucleate (arrested telophase) stages, predominant in all populations, revealed the microtubular nature of the extranuclear spindle which extends between the 2 polar complexes each adjacent to one of the nuclei. The spindle microtubules originate in paired, nonperiodic structures apparently homologous to the “atractophores” described from hypermastigotes. To the external surface of the atractophores are applied periodic elements, which extend laterally as the parabasal filaments. Extensive Golgi complexes overlie the filaments, these structures corresponding to the components of the parabasal apparatus known from trichomonads and hypermastigotes. The 2‐layered structures, consisting of the atractophores and periodic layers, together with the proximal parts of the Golgi complex and the spindle microtubules constitute the polar complex. No kinetosome‐ or centriole‐like organelles have been found in the polar complexes or elsewhere in the organism. The extranuclear spindle is composed of 2 microtubule bundles, each with ∼30‐40 microtubules. One of the bundles always appears at some distance from the nucleus; the other is juxtanuclear and is seen often to course within a groove of the nuclear envelope. A 3rd bundle of ∼35‐45 microtubules is seen on occasion to arise from the atractophores and to pass toward the nucleus at a wide angle to the other parts of the spindle. In some instances these microtubules traverse the nucleus within channels delimited by the nuclear envelope. The double‐layered nuclear envelope contains numerous pores. Two morphologic types of rounded inclusions, one microbody‐like, and the other with a more electron‐translucent matrix, as well as digestive vacuoles containing rice starch, bacteria, and/or myelin configurations are distributed in the cytoplasm, which abounds also in glycogen granules.

The fine structure of Dientamoeba is compared with those of trichomonads and of Entamoeba spp. The taxonomic position of Dientamoeba is discussed and emended; in view of its affinities, this genus is placed among trichomonads in the family Dientamoebidae Grassé, emend.
Nutritional Study of Three Strains of Naegleria gruberi*
Authors: O'DELL WILLIAM D. , BRENT MORGAN M.
Published: May 2007

SYNOPSIS

Naegleria gruberi strains cloned from amebas isolated from a Vero cell culture (“TS”), a sewer drainage ditch (“PD”), and an established laboratory line (“S”) were morphologically identical except for differences in size and flagellate transforming ability. Cultivation on a Trypticase‐yeast extract‐glucose medium (“TYG”) fortified with autoclaved E. coli resulted in increased cell size of 2 strains. Differences also were noted in growth rates and optimal growth temperatures. The autoclaved E. coli in TYG medium was replaceable with serum only for strains TS and PD. A basal salts medium + autoclaved E. coli supported growth of all 3 strains, but the basal salts medium + serum would not support growth of any of the strains.
Light and Electron Microsopic Observations on the Pathogenesis of Naegleria fowleri in Mouse Brain and Tissue Culture
Authors: VISVESVARA G. S. , CALLAWAY C. S.
Published: May 2007

SYNOPSIS

Two strains of pathogenic Naegleria were employed to infect mice and monkey kidney (Vero line) cell cultures. Mice were infected intranasally. Moribund mice were sacrificed and their brains processed for light and electron microscopy. The normal architecture of the infected brain was completely destroyed; the olfactory lobes and the cerebral cortex showed the heaviest damage. The inflammatory response was mainly in the form of neutrophil polymorphs (PMN) and was confined to the olfactory lobes and the superficial regions of cerebral cortex. Numerous amebas were seen interspersed with the degenerating neurons, glial processes, and PMN. Most conspicuous were the food vacuoles which contained host tissue in various stages of digestion. Amebas in the brain tissue also produced many micropinocytotic vesicles from the surface of the plasma membrane. These vesicles are interpreted as vehicles of transport of nutritive materials from the host tissue. The infected cell culture showed the characteristic cytopathic effect (CPE). The CPE was chiefly in the form of cell shrinkage, nuclear pycnosis and discontinuity of cell sheet. Amebas were often seen in an intracellular location. The Vero cells produced many fuzzy pinocytotic vesicles at these loci where the ameba plasma membrane and Vero cell membrane were in close apposition; the probable significance of this is discussed. Most impressive, however, were the pseudopodial formation and capturing of the host material which indicated the great phagocytic activity of the amebas. This was confirmed further by the presence of large numbers of food vacuoles containing host material in various stages of digestion. These observations show that the amebas invade and destroy the brain tissue by active phagocytosis.
Selectivity of Ingestion and Digestion in the Chrysomonad Flagellate Ochromonas malhamensis
Authors: DUBOWSKY NATHAN
Published: May 2007

SYNOPSIS

Ochromonas malhamensis cells were allowed to feed on autoclaved Aerobacter aerogenes, biochemically inert polystyrene latex particles of comparable size, shape and density, or a combination of these to determine if this protozoan is capable of phagotrophic selectivity under defined experimental conditions. Electron microscopic examination of Gomoristained food vacuoles indicated that the type of particle ingested was determined entirely by the type available. Apparently the biochemical or physical configuration of the particle surface is not decisive in particle selection. Gomori acid‐phosphatase reaction product, which indicates digestive enzyme activity, was present in all particle‐containing vacuoles, suggesting that digestive activity in O. malhamensis is due to the presence of particulate material in the vacuole, but not necessarily to the nature of the particle.
Cell Division in Gonyaulax catenella, A Marine Catenate Dinoflagellate*
Authors: TOMAS RONALD N.
Published: May 2007

SYNOPSIS

Mitosis and cytokinesis are described and illustrated for the first time in the mesokaryotic, catenate dinoflagellate Gonyaulax catenella. A structure similar to the central body of G. tamarensis and G. monilata is shown by light and electron microscopy to be situated intranuclearly near the arms of the U‐shaped interphase nucleus, and is suggested to function in the segregation of daughter chromosomes. This structure has the fine structure of a nucleolus, and it is suggested that the term central body be replaced by persistent nucleolus (= endosome). The time required for the completion of mitosis is 4–6 hr, while cytokinesis requires at least 2 hr. Cytokinesis begins during the mitotic cycle, and the plane of fission is perpendicular to the mitotic plane of division. Parental fission moieties are retained and shared by the daughter cells while either a new antero‐sinistral moiety or a posterodextral moiety is synthesized by the dividing cell.
Ultrastructural Analysis of Plasmodium berghei Sporozoite Antigens Prepared by Freeze Thawing and Heat Inactivation*
Authors: JAKŠTYS BIRUTE P. , ALGER NELDA E. , HARANT JOYCE A. , SILVERMAN PAUL
Published: May 2007

SYNOPSIS

Ultrastructural analysis was performed on freeze‐thawed and heat inactivated Plasmodium berghei NK65 sporozoite preparations, which in parallel studies served as the immunogens against a malarial infection in A/J mice. Sporozoites in the freeze‐thawed sample appeared severely damaged with most of their cytoplasmic contents lost. The heat inactivated sporozoites remained intact and closely resembled the untreated controls.
Biochemical Cytology of Trichomonad Flagellates. II. Subcellular Distribution of Oxidoreductases and Hydrolases in Monocercomonas sp.*
Authors: LINDMARK DONALD G. , MÜLLER MIKLÓS
Published: May 2007

SYNOPSIS

A primitive trichomonad, Monocercomonas sp. (strain NS‐1:PRR) from Natrix sipedon, was grown axenically in Diamond's medium. Activity of NADH oxidase, malate dehydrogenase, malate dehydrogenase (decarboxylating) and of the anaerobic enzymes, pyruvate synthase and hydrogenase as well as of several hydrolases was demonstrated in homogenates. The subcellular distribution of these activities was studied by means of analytical differential and isopycnic centrifugation of homogenates prepared in 0.25 M sucrose. NADH oxidase and malate dehydrogenase are in the nonsedimentable part of the cytoplasm. Malate dehydrogenase (decarboxylating), pyruvate synthase, and hydrogenase are associated with a large particle which equilibrates at density 1.22. In its properties, this particle corresponds to the microbody‐like hydrogenosomes of Tritrichomonas foetus. The 5 hydrolases studied are associated with at least 2 different particle populations: a large particle population equilibrating at densities from 1.10 to 1.16 is the exclusive location of 3 enzymes (β‐galactosidase, protease and β‐N‐acetylglucosaminidase), 2 of which have a pH optimum close to neutrality. These particles contain part of the acid phosphatase and β‐glucuronidase. Another part of these 2 enzymes is associated with a separate population of smaller granules with equilibrium densities of 1.16 to 1.18. The 2 types of hydrolase‐carrying particles are also biochemically very similar to their counterparts in T. foetus.