bluuebunny/crossref_metadata_2025 huggingface dataset:
Transfer of Photosynthetically Produced Carbohydrate from Endosymbiotic Chlorellae to Paramecium bursaria*
Authors: BROWN JACK A. , NIELSEN P. JAMES
Published: May 2007

SYNOPSIS

Paramecium bursaria (Ehrenberg) and an endozoic zoochlorella Chlorella conductrix (Brandt) live in a symbiotic relationship. Uptake of NaH14CO3 was studied to determine if carbohydrate products of photosynthesis are transferred to the host paramecium.

Paramecium bursaria containing the algal symbionts took up NaH14CO3 but those without the algal symbionts did not. Radioactive maltose, glucose, fructose and malate were identified from the ethanolic extract of paramecia.

Transfer of materials from Paramecium to Chlorella and the transfer of other materials from Chlorella to Paramecium, led to the conclusion that this is a mutualistic relationship, both organisms benefiting from the relationship.
Antigenic Makeup of Subcellular Fractions of Trypanosoma cruzi
Authors: SEGURA ELSA LEONOR , CURA ESTELA N. , PAULONE IRENE , VASQUEZ CESAR , CERISOLA JOSE A.
Published: May 2007

SYNOPSIS

Trypanosoma cruzi epimastigotes from cultures were separated into nuclear, mitochondrial, lysosomal, microsomal, and cell‐sap fractions. Enzymic and ultrastructutal controls served to determine the cleanness of separation. The bulk of the DNA was in the nuclear (78%) and mitochondrial (12%) fractions. RNA was found in microsomal (74%) and cell‐sap (14%) fractions. Marker enzyme distribution (succinic dehydrogenase, acid phosphatase, and glucose‐6‐phosphatase) was compared with their distribution in mammalian tissues. Subcellular localization of antigens by Ouchterlony tests revealed 2 specific precipitin lines in cell sap and 1 in the microsomal fraction. These antigens may prove diagnostically and immunoprotectively valuable.
The Glucose Transport System in Leishmania tropica Promastigotes*
Authors: SCHAEFER FRANK W. , MARTIN ELMER , MUKKADA ANTONY J.
Published: May 2007

SYNOPSIS

Transport of glucose by Leishmania tropica promastigotes was measured by the uptake of the nonutilizable glucose analog, 2‐deoxy‐D‐glucose (2‐DOG), using the rapid filtration method. Both D‐glucose and 2‐DOG show identical rates of initial uptake. Intracellular 2‐DOG readily exchanges with extracellular D‐glucose and 2‐DOG uptake is competitively inhibited by D‐glucose. These observations suggest that both sugars are taken up by the same system. Neither the glucose analog α‐methyl‐D‐glucoside (α‐MG) nor 3‐0‐methyl glucose (3‐0‐MG) is taken up to any appreciable extent. Transport of 2‐DOG shows saturation kinetics with a Vmax of 3.2 nmoles/mg cells/min and a Km of 0.16 mM. There is thus a stereospecific, carrier‐mediated transport system for glucose uptake in L. tropica. About 2/3 of the intracellular pool following transport consists of 2‐deoxy‐D‐glucose phosphate (2‐DOG‐P) and the remainder is free, unaltered 2‐DOG.
Studies on the Storage Polysaccharides of the Coccidia Eimeria bovis and Eimeria stiedai
Authors: RYLEY JOHN F. , GORDON RONALD W. , STARK J. ROGER
Published: May 2007

SYNOPSIS

Polysaccharides have been isolated from Eimeria bovis and E. stiedai by the use of alkali. The purified polysaccharides stain purple with iodine and have been shown by chemical and enzymic means to be amylopectin. The storage amylopectins of these coccidia differ slightly from typical plant amylopectins in their fine structure.
Nucleic Acid Precursor Incorporation by Eimeria nieschulzi (Protozoa: Apicomplexa) and Jejunal Villus Epithelium*
Authors: MAYBERRY LILLIAN F. , MARQUARDT WILLIAM C.
Published: May 2007

SYNOPSIS

Autoradiography was used to investigate incorporation of tritiated adenine, adenosine, guanosine and thymidine by Eimeria nieschulzi and rat jejunal villus epithelial cells. At 2 1/2 days postinoculation, parasitized and control tissues were incubated for 20 min in oxygenated Tyrode's solution (37 C, pH 7.5) containing 30 μCi/ml of each nucleic acid precursor. Treatment of tissues with ribonuclease revealed that E. nieschulzi incorporated label from [3H]adenine primarily into RNA while that from [3H]adenosine and [3H]guanosine was present mainly in DNA. Label from [3H]thymidine was not utilized by parasites. Host villus epithelial cells incorporated label from [3H]purines primarily into RNA. Labeled cytoplasmic RNA was significantly increased in parasitized cells after incubation in [3H]adenine. Tritiated nuclear RNA and cytoplasmic RNA were significantly decreased in parasitized cells after incubation in [3H]adenosine. Incorporation of label from [3H]guanosine was similar for parasitized and control cells. A small quantity of label from each [3H]precursor was incorporated into DNA of villus epithelial cell nuclei.
Morphometric Studies of Mitochondria in Tetrahymena pyriformis Exposed to Chloramphenicol or Ethidium Bromide*
Authors: KAY EDWIN , ROHATGI KALPANA , KRAWIEC STEVEN
Published: May 2007

SYNOPSIS

Cultures of Tetrahymena pyriformis strain ST were exposed to 300 μg chloramphenicol/ml or 15 μg ethidium bromide/ml for 48 hr. Qualitative assessments of electron micrographs reveal that the abundance of mitochondrial cristae decreases greatly. By equating the spatial characteristics of the organism with those of a prolate spheroid, the distribution and abundance of mitochondria were quantified. Such characterizations reveal that the size of individual mitochondria decreases by 35–60% and that the number of mitochondria/cell increases ∼8 fold. The observations are discussed in terms of coordinated mitochondrial and nuclear genetic activities.
Etude Ultrastructurale de Différents Types de Kystes d'Opalines
Authors: MIGNOT JEAN‐PIERRE , BRUGEROLLE GUY
Published: May 2007

RESUME

Deux types de structure kystique ont été observés au microscope éectronique. Dans le ler, qui correspond aux kystes d'infection ou gamontokystes, la cellule est relativement libre dans l'enveloppe kystique. Celle‐ci est formée de 2 couches distinctes d'inégale épaisseur (ectokyste, endokyste) sécrétées par la cellule et doublées intérieurement par un mince feuillet cytoplasmique dûà une extension des plis cuticulaires. C'est la seule modification du cortex cellulaire.

Par contre, dans le 2ème type les modifications sont beaucoup plus importantes. La cellule est étroitement accolée aux parois du kyste; crêtes et flagelles ont disparu de la surface. Cependant on retrouve leurs traces dans la région corticale, sous forme d'axonèmes intracytoplasmiques plus ou moins désorganisés et d'empilements de saccules associés à des rangées de microtubules. Ce seraient des kystes de résistance. Les structures observées dans ces derniers kystes nous permettent de discuter quelques idées sur la participation des microtubules et des systèmes membranaires à la morphogénèse du cortex des Opalines.
Haemogregarina pseudemydisn. sp. (Apicomplexa: Haemogregarinidae) andPirhemocyton chelonarumn. sp. in Turtles from Louisiana*
Authors: ACHOLONU ALEXANDER D.
Published: May 2007

SYNOPSIS.The blood of each of 95 turtles (8 species) collected from southeastern Louisiana was infected with some or all of the merogonic stages and gametocyte stage ofHaemogregarina pseudemydisn. sp. Five species of turtles harboredPirhemocyton chelonarumn. sp. TurtleHaemogregarinaandPirhemocytonare locality records for Louisiana.Pirhemocytonis reported for the first time in turtles and in the continental U.S.A.
A Comparative Electron Microscopic Study of the Morphology of Toxoplasma gondii by Freeze‐Etch Replication and Thin Sectioning Technic
Authors: SULZER ALEXANDER J. , STROBEL PHYLLIS L. , SPRINGER E. LOUISE , ROTH IVAN L. , CALLAWAY CAREY S.
Published: May 2007

SYNOPSIS. Freeze‐etch preparations of Toxoplasma gondii reveal details of structure and organelles in 3‐dimensional relationships. The subpellicular microtubules and their relationship to the polar ring, the tripartite pellicle, the pellicle constituents, and the spatial relationship of the rhoptries to the conoid and conoid canal are clearly demarcated.
Besnoitia jellisoni in Macrophages and Cysts From Experimentally Infected Laboratory Mice*
Authors: SÉNAUD J. , MEHLHORN H. , SCHOLTYSECK E.
Published: May 2007

SYNOPSIS. Besnoitia jellisoni from experimentally infected laboratory mice (Mus musculus) was studied by means of electron microscopy. After inoculation into the peritoneal cavity, the parasites were often found within vacuoles in macrophages, in which they underwent multiplication. About 10 days after inoculation, the peritoneal fluid became free of macrophages with parasites. The latter were then seen not earlier than 3–8 weeks later within cysts, which were distributed within the reticular endothelial system indicating transport of the parasites by macrophages. Within macrophages and cysts the parasites reproduced by endodyogeny and occasionally by endopolygeny. In serial sections of some specimens, the inner membranes of the daugther merozoites were found to be continuous with the endoplasmic reticulum (ER). Cytochemical studies showed that acid phosphatase was present within the ER and between the inner membranes of the pellicle. These findings indicate the origin of the inner membranes from the ER.
Ultrastructural Localization of Acid Phosphatase in Starved Tokophrya infusionum*
Authors: RUDZINSKA MARIA A.
Published: May 2007

SYNOPSIS. Young organisms of Tokophrya infusionum starved for several hr, are best suited for a study of the fine structure of this organism including the distribution of its organelles. Acid phosphatase was localized by a combined electron microscopy and cytochemical approach using modified Gomori methods. The enzyme was found in small dense bodies, spheroid vesicles, missile‐like bodies, rough‐surfaced endoplasmic reticulum, residue and autophagic vacuoles. The small dense bodies are thought to be primary lysosomes since electron micrographs show a) a continuity between the membrane of the rough‐surfaced endoplasmic reticulum and that of the dense bodies and b) a connection between the contents of both structures when the dense bodies form from the endoplasmic reticulum.
Differential Nuclear Coloration in Ciliates
Authors: ALONSO PILAR
Published: May 2007

SYNOPSIS. Application of the triple stain of Grosso (methyl green‐pyronin‐orange G) to the exconjugants of different species of ciliates produces a differential coloration of their nuclei. Both the old macronucleus or its remnants and the micronuclei bind methyl green whereas the newly developing macronucleus (macronuclear anlage) has a selective affinity for the orange G present in the mixture. This finding holds true not only for hypotrichous ciliates, whose macronuclear anlagen are involved in the formation of polytene chromosomes, but also for other ciliates not included in the order Hypotrichida. Such a reaction of the new macronuclei apparently results from the presence of non‐histone (acidic) proteins associated with the nucleic acids.

The staining method is fully described to provide a more general application.
Syngenic Divisions of the Cellular Slime Mold Polysphondylium violaceum*
Authors: CLARK MARY ANNE
Published: May 2007

SYNOPSIS. Mating type analysis of new isolates of Polysphondylium violaceum supports the subdivision of this morphological species into two reproductively isolated breeding groups or syngens. Representatives of both syngens have been identified in soil samples taken from widely separated geographical locations. Intersyngenic cross reactions have been observed in some stocks.
Isolation of Kinetoplast‐Mitochondrial Complexes from Leishmania tarentolae*
Authors: BRALY PATRICIA , SIMPSON LARRY , KRETZER FRANK
Published: May 2007

SYNOPSIS. Kinetoplast‐mitochondrial complexes were liberated from Leishmania tarentolae by passing hypotonically swollen cells in dilute Tris‐EDTA through a needle at 100 1bs/in2. The complexes formed an equilibrium band by flotation in Renografin gradients at a density of 1.22 g/ml. The band was monitored by several mitochondrial and kinetoplastic markers: [3H]DNA, succinate‐cytochrome c reductase activity, [50Fe]hemoproteins and optical density at 600 nm. Electron microscopy showed that the sole component of the 1.22 g/ml band was the kinetoplast‐mitochondrial complex.
Die Entwicklung von Acanthamoeba castellanii zur Cyste mit und ohne Veränderung des Genaktivitätsmusters*
Authors: JANTZEN H.
Published: May 2007

Die Hemmung der mitochondrialen DNS‐Snythese von Acanthamoeba castellanii der logarithmischen Wachstumsphase durch Äthidiumbromid induziert die stationäre Wachstumsphase, in deren Verlauf Cysten gebildet werden. Diese Cystenbildung ist, im Gegensatz zu der durch Sauerstoff oder Nahrungsmangel hervorgerufenen, nicht von einer in DNS‐RNS‐Hybridisierungen nachweisbaren Synthese qualitativ neuer RNS‐Arten begleitet.

Wahrend der durch Äthidiumbromid, Sauerstoff‐ und Nahrungsmangel induzierten stationären Wachstumsphase und Encystierung findet eine starke Reduktion des [3H]Uridin‐Einbaus in die RNS statt; davon ist die ribosomale stärker als die niedermolekulare RNS betroffen.

In der durch Äthidiumbromid induzierten stationären Wachstumsphase und in der späten 1WP sind in der RNS weniger DNS‐ähnliche RNS‐Arten vorhanden als in der frühen logarithmischen Wachstumsphase.
Purification and Characterization of Malic Enzyme of Entamoeba invadens: Evidence for Isoenzymes*
Authors: BURO NICHOLAS C. , WELLER DAVID L.
Published: May 2007

SYNOPSIS. Malic enzyme (EC 1.1.1.40) of Entamoeba invadens seems to be a single species of protein on zone‐sedimentation, gel filtration, and gel electrophoresis. The molecular weight of the enzyme was estimated to be 120,000 and sedimentation coefficient close to 6S. Isoelectric focusing, however, showed malic enzyme to be composed of three isoenzymes of pI 5.8, 6.0, and 6.3. A procedure is described that yields an electrophoretically pure sample of each of the isoenzymes suitable for physical and chemical studies.
Prokaryote Affinities ofDuboscqia penetransThorne
Authors: MANKAU R.
Published: May 2007

SYNOPSIS.The obligate endoparasite of soil nematodes, described originally asDuboscqia penetransThorne, 1940, was proved to be incorrectly classified as a member of the genusDuboscqia(Protozoa, Microspora). Spores of this parasite were found to lack a polar filament, PAS‐positive polar cap, or any other features characteristic of the microsporan protozoa. The organism has a simple vegetative cycle within the host and its spore resembles the “endospore”common inBacillusspp. It appears to have strong affinities to the etiologic agents (Bacillus popilliae) of the “milky disease”of certain insects.
Fine Structure of the Endogenous Stages of Eimeria labbeana. I. The First Generation Merozoites
Authors: VARGHESE THOMAS
Published: May 2007

SYNOPSIS. The fine structure of the 1st generation merozoites of Eimeria labbeana from the ileal mucosa of artificially infected pigeons (Columba livia) was investigated and described. The 1st generation merozoites which appeared between 36‐48 hr after infection averaged 4.4 × 2.1 μm in size. The 3‐membraned pellicle was irregular in texture and harbored a single micropore, and many micropore‐like invaginations. Closely apposed to the inner pellicular membrane were seen 22 microtubules, each 22–25 nm in diameter. An apical vesicle, 50 nm in diameter, seen at the anterior extremity, was connected with the common duct of the micronemes. The conoid consisted of 9 spiral elements, each 30 × 25 nm. The paired organelle (rhoptries) varied in length (1.4–2.2 μm), and the ductules (23 nm diameter) were composed of 2 inner tubules, each 6 nm in diameter. A unit membrane enveloped the partially alveolar and differentially osmiophilic interior of the bulbous regions of the rhoptries. The “rod‐like structure”was found to be tubular and represented the common duct of the micronemes.
L'Appareil Fibrillaire Buccal Isolé de Turaniella vitrea et son Evolution au Cours de la Stomatogenèse
Authors: et Jean Grain FRANCINE IFTODE
Published: May 2007

RESUME. L'isolement de l'appareil buccal de Turaniella permet une description précise de l'architecture des fibres dont il est constitué. Les changements dans la forme et la cohésion de ces fibres au cours de la stomatogénèse ont été suivis. Leur disparition dans le proter au début de la division est confirmée; leur reconstitution chez les tomites après la division est très lente. Des digestions protéolytiques et des colorations spécifiques montrent que les fibres buccales sont de nature protéique avec une forte tendance à la basicité.

SYNOPSIS. A light microscopic study of the isolated buccal apparatus of Turaniella vitrea, a hymenostome peniculine ciliate, resulted in an accurate description of the fibers constituting this apparatus. Changes in shape and cohesion of the fibers during stomatogenesis were also followed. The loss of the fibers in the proter early in division was confirmed. Their reconstitution in the tomites following division was found to be very slow. It was demonstrated with the aid of cytochemical methods and proteolytic enzyme digestion that the fibers consist of mostly basic proteins.
Cultivation of Acanthamoeba castellanii, Neff Strain, at High Hydrostatic Pressures
Authors: TODD S. R. , KITCHING J. A.
Published: May 2007

SYNOPSIS. Log‐phase cultures of Acanthamoeba castellanii, Neff strain, have been maintained at elevated hydrostatic pressures over periods of several days and the population has been recounted at the end of the experimental period. A pressure of 2,000 psi (136 atm) depressed growth of the population, but was quickly reversed on release. A pressure of 4,000 psi (272 atm) severely depressed population growth, and any increase was slight and short‐lasting at 5,000 psi (340 atm). Growth of the population was resumed only after an interval of 1 or more days after release.
Growth of Nosema algerae in Pig Kidney Cell Cultures*
Authors: UNDEEN ALBERT H.
Published: May 2007

SYNOPSIS. Nosema algerae, a microsporidan parasite of mosquitoes, can infect pig kidney cell cultures. Spores germinated in the culture medium, infected the cells within 30 min of germination, multiplied, and produced spores. The early developmental stages in the N. algerae life cycle are described.
Light and Electron Microscopic Observations on the Heterotrich Ciliate Climacostomum virens
Authors: PECK ROBERT , PELVAT BERNARD , BOLIVAR IGNACIO , DE HALLER GERARD
Published: May 2007

SYNOPSIS. Alveolar membranes and an epiplasm exist under the cell membrane of the noncontractile heterotrich ciliate Climacostomum virens. Postciliary microtubular ribbons join at the right of each somatic kinety to form a Km fiber. Two transverse microtubular fibers occur per kinetosomal pair. A myonemal network interconnects the kinetosomal bases intrakinetally and interkinetally. Ultrastructural comparisons are made between the contractile and noncontractile heterotrichs.

The buccal cortex consists of an adoral zone of membranelles, a peristomal field, a buccal tube, the apical membranelles, and a haplokinety. The kineties of the peristomal field and buccal tube are rows of paired kinetosomes, with a postciliary ribbon of microtubules arising from the posterior kinetosome of each pair, and a transverse ribbon and an oblique ribbon from the anterior kinetosome. No Km fibers exist in this region. The haplokinety is a collar of paired kinetosomes surrounding the cytostome; a postciliary microtubular ribbon descends from each kinetosomal pair into the cytostomal region. Ultrastructural details of the buccal cortex of C. virens and other heterotrichs are compared. The nemadesmata which lie under the membranelles are implicated in the body bending of C. virens.

Algae endosymbiotic in the cytoplasm of C. virens are described.
Scanning Electron Microscopy of Stomatogenesis Accompanying Conjugation in Euplotes aediculatus*
Authors: KLOETZEL JOHN A.
Published: May 2007

SYNOPSIS. The succession of morphologic changes in the feeding apparatus (peristome) accompanying conjugation and postconjugant development in the hypotrich Euplotes aediculatus has been examined by scanning electron microscopy (SEM). The details of stomatogenesis inferred from earlier light‐microscopic studies of silver‐stained preparations have been confirmed and extended.

The elaborate peristome is the dominant surface feature of vegetative Euplotes. In conjugation, the ciliates are joined in their peristomial regions; as the conjugants separate, the old feeding apparatus is seen to be disrupted and partially resorbed. In its place is the crescent‐shaped primordium of a new peristome, which develops as part of a general cortical reorganization. This primordium expands anteriorly, unfurling a new crown of ciliary membranelles that soon replaces the remaining preconjugant membranellar band. The resulting “exconjugant peristome'’is characterized by a greatly reduced number of adoral membranelles and the absence of paroral membranelles, buccal cavity, and cytostome. Exconjugants thus cannot feed for 2–3 days, until the missing peristomial components are replaced. This occurs by means of a 2nd cortical reorganization, during which new membranelles, developing from another peristomial rudiment, are added directly to the abbreviated exconjugant set. A new buccal cavity is concurrently sculpted as the primordial depression enlarges, and the cells can resume feeding sometime during the 4th day after separation.

The implications of this mode of stomatogenesis and the nonfeeding condition are discussed, as are the advantages of SEM for studies of ciliate morphogenesis.
Conjugation in the Hypotrich Ciliate, Paraurostyla weissei (Stein): A Scanning Electron Microscope Study*
Authors: HEUMANN JOHN
Published: May 2007

SYNOPSIS. Conjugation in Paraurostyla weissei has been investigated by scanning electron microscopy. In the course of conjugation, one member of each conjugating pair is resorbed. An organism that is being resorbed always lies to its partner's left and is always fused to its partner's oral region. A mechanism for the development of this asymmetry is proposed, based on the asymmetry of individual Paraurostyla. After resorption is complete, exconjugants enter a rounded, nonmotile stage which lasts several days. Exconjugants at this stage have been compared with cysts and have been found to be dissimilar.
Effect of Adenine on Paramecium multimicronucleatum*
Authors: MISHIMA SHOJI
Published: May 2007

SYNOPSIS. The addition of adenine to the culture medium of Paramecium multimicronucleatum caused an inhibition of conjugation and fission and also an increase in the number of food vacuoles. The inhibition of conjugation was observed at the stage of adhesion of cell membranes. With adenine, the duration of fission was prolonged and L‐shaped cells were formed. Adenine apparently repressed the excretion of food vacuoles and thus caused an accumulation of food vacuoles within the cells. All these effects were observed at similar concentrations of adenine higher than 2 mM. The addition of uridine to the adenine‐containing medium reversed the inhibition of fission; conjugation and vacuole accumulation remained unaffected.
Eimeria cicaki sp. n. and Isospora thavari sp. n. from the House Lizard Gehyra mutilata Boulenger in Malaysia*
Authors: ELSE JAMES G. , COLLEY FREDERICK C.
Published: May 2007

SYNOPSIS. Oocysts and endogenous stages of new species of Eimeria and Isospora from the house lizard, Gehyra mutilata, are described. The ellipsoid to subspherical 2‐layered oocysts of E. cicaki averaged 24.0 × 21.0 μm. Polar granules are present. Micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.2 × 9.0 μm. A sporocyst residuum is present, but the Stieda body is absent. Endogenous stages are in epithelial cells of the small intestine. The subspherical single‐layered oocysts of I. thavari average 23.8 × 22.8 μm. The polar granule is present; micropyle and oocyst residuum are absent. Ellipsoid sporocysts average 12.8 × 9.4 μm. Stieda body and sporocyst residuum are present. There are endogenous stages in epithelial cells of the small intestine.
Encephalitozoon sp. in the Blue‐Masked Lovebird, Agapornis personata (Reichenow): First Confirmed Report of Microsporidan Infection in Birds
Authors: KEMP R. L. , KLUGE J. P.
Published: May 2007

SYNOPSIS. A microsporidan tentatively classified as Encephalitozoon sp. on the basis of structure and tinctorial qualities was identified in tissues from a group of blue‐masked lovebirds, Agapornis personata (Reichenow). The organism was present in renal tubular epithelial cells, hepatocytes, bile duct epithelial cells, and intestinal epithelial cells. Focal hepatic necrosis occurred around clusters of the organisms but inflammation was minimal or absent in the other infected tissues. Attempts to infect laboratory mice with the organism were unsuccessful. Ultrastructural features were compared with those of E. cuniculi of mammals.
Serum Proteins Promoting [3H]Thymidine Uptake by Trypanosoma (Schizotrypanum) cruzi (Chagas) in vitro
Authors: O'DALY JOSE A.
Published: May 2007

SYNOPSIS. Five proteins capable of stimulating [3H]thymidine uptake by Trypanosoma cruzi in vitro were isolated from fetal calf serum by (NH4)2SO4 precipitation and ion exchange column chromatography. The proteins were partially characterized by immunodiffusion, immunoelectrophoresis, polyacrylamide gel disc electrophoresis, and SDS electrophoresis. As estimated by SDS electrophoresis, using 4 standards, the molecular weight of protein 1 was 100,000, that of protein 2 was 76,000. and that of proteins 3–5 was 68,000 daltons.
The Ribosomes of the Simian Malaria, Plasmodium knowlesi. I. Isolation and Characterization*
Authors: SHERMAN IRWIN W. , COX R. A. , HIGGINSON B. , McLAREN D. J. , WILLIAMSON J.
Published: May 2007

SYNOPSIS. Monomeric ribosomes, isolated from the monkey malaria Plasmodium knowlesi by the combined use of low concentrations of Triton X‐100 and differential centrifugation, sedimented in the SOS range and could be dissociated into 60 and 40S subparticles. The base composition of the rRNA was typically protozoan; that is, low in guanine and cytosine residues.
The Life Cycle of the Histophagous Ciliate Tetrahymena corlissi Thompson, 1955*
Authors: LYNN DENIS H.
Published: May 2007

SYNOPSIS

The life cycle of Tetrahymena corlissi Thompson, 1955, is described from organisms fed on tissue of the oligochaete Enchytraeus. The trophont stage usually divides twice either while free‐swimming or encysted as a tomont. The tomont stage apparently occurs only when the trophont is removed from the “conditioned” tissue environment. The time to completion of division is constant and determined at the onset of exposure to tissue. The number of divisions is a function of the amount of tissue ingested. Tomites differentiate after the divisions as active theronts. This dispersal stage transforms to a trophont when tissue is ingested. If tissue is absent, the theronts become smaller, eventually settling on the substrate as immotile pyriform resting theronts, with a small proportion of the resting theronts encysting within a delicate cyst wall. When stimulated chemically or mechanically, the resting theronts transform to active theronts. If these active theronts ingest tissue, they transform to immature trophonts, initially incapable of division. Life cycle and morphologic dissimilarities among T. corlissi, T. bergeri, and T. rostrata are presently used to distinguish among these species.
Quelques Précisions sur L'ultrastructure de Sarcocystis tenella. I. L'endozoïte (Après Coloration Négative)*
Authors: PORCHET‐HENNERE E.
Published: May 2007

RESUME

Des préparations en coloration négative d'endozoïtes de Sarcocystis tenella ont permis de préciser certains points de sa structure. Le conoïde est constitué d'une vingtaine de fibres obliques et surmonté d'anneaux à ornementation régulière. A l'intérieur du conoïde, et en position excentrée, existent 2 microtubules parallèles qui plongent assez profondément dans le cytoplasme sous‐jacent. Les fibres du conoïde, les microtubules intraconoïdaux semblent avoir la même épaisseur et la même structure que less 22 microtubules sous pelliculaires. Ceux‐ci sont “cimentés” vers l'avant en un collier périconoïdal qui coulisse autour du conoïde. La paroi, d'aspect “réticulé” présente quelques différenciations: le micropore cerclé d'un élément “fibrillaire,” une dizaine de structures subcirculaires en couronne vers l'avant, et 11 lignes de granulations convergeant vers le pôle postérieur. Les sarconèmes se présentent comme des navettes indépendantes les unes des autres et, contrairement aux estimations précédentes, il est établi qu'il n'existe que 2 rhoptries.

SYNOPSIS

The employment of negative staining technics for the endozoites (cyst stages) of Sarcocystis tenella allowed the elucidation of certain aspects of their fine structure. The conoid consists of ∼ 20 oblique fibers and is surmounted by a ring with regular ornamentation. In the conoid's interior there are 2 excentric parallel microtubules which extend posteriorly for a considerable distance into the adjacent cytoplasm. The fibers of the conoid, the intraconoid microtubules, appear to have the same diameter and structure as the 22 subpellicular microtubules. They are “cemented” anteriorly into a periconoidal ring which surrounds the conoid. The “reticulated” pellicle has certain differentiations: the micropore, surrounded by a “fibrillar” element, ∼ 10 subcircular structures arranged into an anterior crown, and 11 rows of granules converging toward the posterior end. The sarconemes look like rice grains which, contrary to previous statements, are independent of one another. It is established that there are only 2 rhoptries.
Comparative Studies on Related Free‐Living and Pathogenic Amebae With Special Reference to Acanthamoeba*
Authors: VISVESVARA G. S. , BALAMUTH W.
Published: May 2007

SYNOPSIS

Comparative studies were conducted on the structure, nutrition, protein composition, immunology, and effect on cell cultures of Acanthamoeba sp. (Lilly A‐1 strain), A. castellanii (Singh and Neff strains), A. astronyxis, A. comandoni, A. polyphaga, A. terricola, Hartmannella vermiformis, and Naegleria gruberi. Lilly A‐1 strain of Acanthamoeba received special attention owing to its pathogenicity for experimental animals. Distinct differences were noted in structure, nutrition, and antigenic composition of Acanthamoeba spp. and Hartmannella, and it was concluded that their recognition as separate genera is justified.

With the exception of A. terricola, all species of Acanthamoeba could be differentiated by cyst structure. Cysts of A. terricola closely resembled those of A. castellanii Singh strain, and close antigenic relationships between these 2 species were demonstrated by gel diffusion and immunoelectrophoresis (IEP); it was concluded that the 2 amebae belong in the same species.

The pathogenic Acanthamoeba sp. Lilly strain differed from the nonpathogenic A. castellanii Singh strain in (a) cyst structure; (b) protein distribution patterns (on disc electrophoresis); (c) soluble and particulate antigens (on gel diffusion, IEP, complement fixation, and immobilization tests); (d) capacity to induce cell‐free plaques and other cytopathic effects (CPE) in mammalian monolayer cell cultures; (e) elimination of a phospholipase, responsible for some of the CPE, into the culture medium, Acanthamoeba sp. Lilly strain, which liberated more phospholipase, produced more CPE.

Acanthamoeba sp. Lilly strain differed also from other species of this genus in cyst structure and antigenic composition. It was concluded, therefore, that, following the recommendation of Singh & Das, it ought to be placed in a separate species, Acanthamoeba culbertsoni.
Antigenic Differences Among Epimastigotes, Amastigotes and Trypomastigotes of Trypanosoma cruzi*
Authors: KLOETZEL JUDITH , CAMARGO MARIO E. , GIOVANNINI VERA LUCIA
Published: May 2007

SYNOPSIS

Antigenic differences were demonstrated among trypomastigotes, amastigotes, and epimastigotes of Trypanosoma cruzi by the indirect fluorescent antibody method. Tests using cross‐absorbed sera were included in the study.
Ultrastructure of the Peripheral Zone of a Glugea‐Induced Xenoma*
Authors: WEIDNER EARL
Published: May 2007

SYNOPSIS. The Glugea stephani‐induced xenoma in the winter flounder, Pseudopleuronectes americanus, is a large spherical host‐parasite complex, up to 4.0 mm in diameter, with the host and parasite components of the xenoma being most active in the peripheral zone. The xenoma has an extensive periodic acid‐silver methenamine‐positive surface coat covering the plasma membrane. The surface of this membrane is amplified by the presence of numerous folds and fine tubular extensions. The peripheral zone of the xenoma contains many host‐cell mitochondria in addition to numerous microsporidan parasites. At the ultrastructural level, the peripheral zone of the host‐cell cytoplasm appears normal. Inside the peripheral region of the 0.4–1.0 mm xenoma, the host‐cell component largely disintegrates in the presence of microsporidan parasites undergoing sporogenesis.
Axenic Cultivation ofPhytomonas davidiLafont (Trypanosomatidae), a Symbiote of Laticiferous Plants (Euphorbiaceae)*
Authors: MCGHEE R. BARCLAY , POSTELL FRED J.
Published: May 2007

SYNOPSIS.Phytomonas davidi(Trypanosomatidae) originally discovered by Lafont in 1909 on the island of Mauritius was rediscovered inEuphorbia cyathophorain Florida. Successful cultures were established in diphasic medium consisting of duck blood agar and modified Phillips’medium as overlay. Optimal growth was obtained when Mansour's medium was used as overlay and poorest growth when Cowperthwaite's medium buffered at pH 5.0 was utilized for this purpose. Marked changes tending toward choanomastigotes rather than the elongate twisted promastigotes were observed in cultures.
Symbiote‐Free Hemoflagellates, Blastocrithidia culicis and Crithidia oncopelti: their Liver Factor Requirement and Serologic Identity*
Authors: CHANG K.‐P.
Published: May 2007

SYNOPSIS. Several aposymbiotic strains of Blastocrithidia culicis and Crithidia oncopelti were cultivated in Trager's chemically defined medium as well as in a blood broth, both supplemented with 0.25% (v/v) liver extract concentrate. For all such strains, the liver extract was found to serve as an essential growth factor in the defined medium and as growth promoting additive in the blood broth. The active molecules were found to be water‐soluble, heat stable, dialyzable, and probably nonlipid fractions.

Antisera were developed in rabbit against all the available aposymbiotic strains. An almost total cross‐reactivity at very high titers was observed in reciprocal agglutination test using strains with and without the bacterial symbiotes. These results indicate that the loss of the symbiotes does not affect the antigenic identity of B. culicis and C. oncopelti.
Observations on Haemogregarina balli sp. n. from the Common Snapping Turtle, Chelydra serpentina*
Authors: PATERSON WILLIAM B. , DESSER SHERWIN S.
Published: May 2007

SYNOPSIS. Haemogregarina balli sp. n. is described from the blood and organs of the common snapping turtle Chelydra serpentina serpentina and from the gastric and intestinal ceca of the presumed invertebrate hosts, the leeches Placobdella parasitica and Placobdella ornata. In the peripheral blood of the turtle, male and female gametocytes and immature erythrocytic schizonts are found within erythrocytes. The maturation of erythrocytic schizonts containing 6–8 merozoites is recorded from liver imprints. Schizonts with 13–25 merozoites are found in various cells of the liver, lung and spleen. In the gastric ceca of the leeches the host erythrocytes are digested, releasing the gametocytes and immature erythrocytic schizonts. Immature erythrocytic schizonts degenerate. Association of the gametocytes occurs in the intestinal ceca. The microgametocyte apparently gives rise to 4 nonmotile microgametes, one of which fertilizes the macrogamete while the other remain as condensed, residual nuclei on the periphery of the developing oocyst. The oocyst increases in size with maturity. A mature oocyst produces 8 sporozoites from a single germinal center. Sporozoites liberated from the oocyst are found in the tissues of the leech. Transovarial transmission of the parasite does not occur in the turtle. Attempts at experimental transmission failed. Previously unfed (control) leeches were negative for the parasite. Haemogregarina balli is compared with other haemogregarines described from C. serpentina. Features of species of Haemogregarina and Hepatozoon as well as the taxonomy of these genera are discussed.
Ultrastructure de Quelques Stades de la Microsporidie Octosporea muscaedomesticae Flu, Parasite de Ceratitis capitata (Wiedemann) (Diptère, Trypetidae)
Authors: ORMIèRES RENE , BAUDOIN JACQUES , BRUGEROLLE GUY , PRALAVORIO RAYMOND
Published: May 2007

La présence de diplocaryons à tous les stades de la sporulation d'Octosporea muscaedomesticae Flu, 1911 est mise en évidence ainsi qu'une membrane pansporoblastique autour des sporoblastes en développement et des spores. Le problème présenté par ces 2 faits est discuté. Une évolution étrange des ribosomes périnucléaires et démontrée. Une telle étude ultrastructurale est nécessaire et intéressante car O. muscaedomesticae est l'espèce‐type du genre Octosporea.
Induction of Phagocytosis and “Cannibalism” by the Giant Ameba, Chaos carolinensis
Authors: LINDBERG ROGER E. , BOVEE EUGENE C.
Published: May 2007

SYNOPSIS. It is evident from studies of cellular recognition resulting in phagocytosis by Chaos carolinensis that cilia from certain protozoa serving as prey, e.g. Tetrahymena pyriformis, influence phagocytic action. Glutaraldehyde‐fixed C. carolinensis to which cilia, isolated from Tetrahymena, are attached by the benzidine reaction, are engulfed by living Chaos but not digested. Fixed Chaos without attached cilia are not engulfed. Adding increased numbers of cilia from Tetrahymena progressively inhibits the rate at which Chaos phagocytizes Paramecium caudatum, suggesting blockage by the cilia of contact sites normally available to initiate phagocytosis of Paramecium.
Observations on Trichosphaerium platyxyrum sp. n.
Authors: ANGELL ROBERT W.
Published: May 2007

SYNOPSIS. Trichosphaerium platyxyrum sp. n., a marine testate rhizopod, is described. The schizont is ∼ 67 /μm in diameter, sheathed with a membranous test of fibrils and matrix covered with thin, straight, blade‐shaped calcitic spicules. The gamont is ∼ 63 μm in diameter with a membranous test devoid of spicules. The tests of both stages contain circular apertures through which extend short dactylopodia. Locomotion is by lobopodia. Both the schizont and gamont are multinucleate with a mean of 38 nuclei/schizont and 23/gamont. Observed reproduction in both is by binary fission with variations described for the gamont. The type locality is the reef flat of Heron Island, Great Barrier Reef, Australia.

It is suggested, but not confirmed, that Schaudinn's description of the life cycle of Trichosphaerium sieboldi may be extended to other species of Trichosphaerium.
Cyclic Changes in Chloroplast Structure in Synchronized Euglena gracilis*
Authors: COOK J. R. , HAGGARD SANDRA SMITH , HARRIS PATRICIA
Published: May 2007

SYNOPSIS. In populations of Euglena gracilis strain Z synchronized by cultivation on a repetitive light‐dark cycle, chloroplasts undergo cyclic changes in structure. During most of the light period chloroplasts are relatively compact with closely appressed lamellae; during the dark (division) period the chloroplasts become quite distended. This change persists for at least one cycle even when the cells are left in continuous light, suggesting that the periodicity may be related more to the age of the cell than to a direct effect of light. In addition, the pyrenoid in synchronized cells has a transient existence, being present only in the first half of the light period.
Electron Microscopic Study of Trypanosoma cruzi Periplast in Tissue Cultures. I. Number and Arrangement of the Peripheral Microtubules in the Various Forms of the Parasite's Life Cycle*
Authors: MEYER H. , DE SOUZA WANDERLEY
Published: May 2007

SYNOPSIS. In an electron microscopic study, counts of peripheral microtubules were made in spheromastigotes and trypomastigotes in tissue cultures of embryonic heart muscle cells. In interphase spheromastigotes there were, at the level of the nucleus, ∼ 114 microtubules; in dividing forms, there were ∼ 222. In trypomastigotes, the number of microtubules varied according to the level of the section—there were fewer than 40 tubules in the pointed ends of an organism, while in the central segment the number of these elements ranged from 60 to 115. The highest number of microtubules was found in the region containing the Golgi complex. The distance between the microtubules was constant, equalling 44 nm, even at the pointed ends of a trypanosome. This suggests that the microtubules course parallel to one another. Cross sections and randomly arranged, variable length, longitudinal sections of the tubules were noted around the kinetosomes in dividing organisms.
Symbiosis in the Larger Foraminiferan Sorites marginalis (with Notes on Archaias spp.)
Authors: MÜLLER‐MERZ EDITH , LEE JOHN J.
Published: May 2007

SYNOPSIS. It was demonstrated with the aid of light and electron microscope studies that Sorites marginalis (Lamarck) harbors zooxanthellae. The hosts were scraped from Thalassia testudinum Konig growing in Key Largo Sound (Florida, U.S.A.) and immediately preserved in appropriate fixatives. Zooxanthellae were distributed unevenly throughout all the chamberlets; only a few symbiotes were found in the embryonic chambers and the inner or outer chambers, but the intermediate chambers were packed with symbiotes. The outer chambers contained many food vacuoles in addition to symbiotes. Some zooxanthellae might have been in the process of degeneration or digestion. The symbiotes were found to have a typical dinoflagellate nucleus, a single large lobate cortical chloroplast with one stalked pyrenoid, an accumulation body, and many starch granules. The nonmotile stage of the zooxanthella was similar, but perhaps not identical, to Symbiodinium microadriaticum Freudenthal from various hosts.

The foraminiferan host is heterokaryotic with hundreds of generative (small) nuclei and scores of vegetative (large) nuclei. Most of the generative nuclei were found in the embryonic apparatus and the inner chambers. Most of the vegetative nuclei were found in the inner and outer chambers.
Effect of Fixation on Demonstration of Phosphatases of Eimeria tenella Grown in Chick Kidney Cell Cultures
Authors: VETTERLING JOHN M. , WALDROP HARRY R.
Published: May 2007

SYNOPSIS. The effects of fixation with various concentrations of glutaraldehyde or formaldehyde, acetone or ethanol, and freeze‐drying on 5 phosphatases of Eimeria tenella and chick kidney cell cultures were demonstrated in situ. Gultaraldehyde inactivated the phosphatases more than did the formaldehyde, but the effect of the combination of the 2 (Karnovsky's fixative) was greater than that of either glutaraldehyde or formaldehyde alone. The higher the concentration of aldehyde and the longer the duration of exposure, the greater the inactivation. The order of sensitivity to aldehyde fixation of the enzymes tested was glucose‐6‐phosphatase > thiamine pyrophosphatase > 5′‐nucleotidase > adenosine triphosphatase > acid phosphatase. Cytologic detail was preserved more efficiently with glutaraldehyde than with formaldehyde. Optimal preservation of enzyme activity for cytochemistry was with 2% glutaraldehyde for 30 min or 2% formaldehyde for 1 hr for G‐6‐Pase. TPPase, and 5′‐nucleotidase, and with 2% glutaraldehyde or 2% formaldehyde for 2 hr with ATPase and AcPase.

Quenching with subsequent fixation in cold acetone or ethanol resulted in complete inactivation of G‐6‐Pase, TPPase, and 5′‐nucleotidase; although cells fixed in this manner yielded large amounts of reaction product for ATPase and AcPase, the distribution was diffuse, and some of it appeared to be artifactual. Quenching with subsequent freeze‐drying was unsatisfactory because nearly all of the cell layers rolled off the cover glasses.
Application of Coriphosphine Staining to the Study of the Macronuclear Anlage of Stylonychia mytilus
Authors: FEDRIANI CONCEPIÓN , TORRES ANTONIO , PÉREZSILVA JULIO
Published: May 2007

SYNOPSIS. Coriphosphine staining of Stylonychia mytilus exconjugants at different times after separation reveals some details of the developing macronucleus. Green fluorescence is seen in both bands and heterochromatic blocks of the polytene chromosomes. No red fluorescence was observed along these chromosomes. Fragments of the old macronucleus and the pycnotic micronuclei have red or orange fluorescence. Red fluorescence is characteristic also of nucleoli in the new macronucleus.
A Role of Calcium Ions in Chemical Induction of Mating in Paramecium tetraurelia*
Authors: CRONKITE DONALD L.
Published: May 2007

SYNOPSIS. Conjugation in Paramecium tetraurelia can be induced within mating‐reactive cultures of a single mating type by treating the cells with solutions of KC1 + acriflavine in culture medium low in Ca2+. Gene mutations with known physiologic effect were used as selective inhibitors of cell surface membrane function to see which functions are necessary for chemical induction of conjugation. The results strongly suggest that a transient increase in the internal concentration of calcium at the very beginning of chemical induction is a necessary but not sufficient step.
Immunologic and Electrophoretic Characteristics of Two Species of Crithidia*†
Authors: DOORIS PATRICIA M. , McGHEE R. BARCLAY
Published: May 2007

SYNOPSIS. Crithidia harmosa and Crithidia fasciculata were compared immunologically by the indirect fluorescent antibody (FA) method and by agglutination. The FA technic yielded more specific results with cellular‐debris than with whole‐cell antigens. The immune sera collected from chickens 9 days after the last inoculations with whole‐cell antigens had higher homologous titers than those collected after 4 days. Major antigenic differences between the 2 species were revealed by both methods. The electrophoretic patterns of C. harmosa and C. fasciculata obtained by polyacrylamide gel slab electrophoresis differed in the numbers and relative mobilities of their component bands.
Effect of Glucose on Glycine Requirement of Acanthamoeba castellanii*
Authors: DOLPHIN WARREN D.
Published: May 2007

SYNOPSIS. Acanthamoeba castellanii grows in a minimal medium (AMLIV) containing only arginine, methionine, leucine, isoleucine, and valine as sole nitrogen sources, other than vitamins, when glucose is the carbon source. With acetate as the carbon source, glycine must be added to AMLIV. Doubling time in AMLIV varies according to the ratio of amino acids concentrations. Several combinations yield Td values of ∼ 70 hr.
The Uptake of Pyrimidine Nucleosides in Tetrahymena. I. Uridine*
Authors: FREEMAN MONA , MONER J. G.
Published: May 2007

SYNOPSIS. Uridine uptake was examined in Tetrahymena pyriformis GL‐7 in defined medium under conditions where food vacuole formation is not a significant factor in solute acquisition by the cell. The results indicate the presence of a saturable mechanism which follows Michaelis‐Menten kinetics. When corrected for diffusion the apparent Km for the carrier is 2.3 ± 0.6 μM and the Vmax is 7.3 ± 0.2 × 10−7 nmoles/cell/min. It is evident from nucleotide pool analysis that most of the radioactivity of externally supplied [3H]uridine appears in UMP with the remainder in UTP. Uridine is apparently phosphorylated immediately upon entry into the cell and neither uridine‐cytidine kinase activity nor RNA synthesis are rate‐limiting in the uptake process. Uridine transport is competitively inhibited by a variety of ribo‐ and deoxyribonucleosides as well as several nucleoside analogs. Neither uracil nor ribose or deoxyribose are effective inhibitors of uridine transport indicating the carrier is specific for the nucleoside. There is little difference between the Ki values for ribo‐ as opposed to deoxyribonucleosides except in the case of deoxyguanosine which is much less effective as an inhibitor under the conditions of this study, than all the other nucleosides, including guanosine.