bluuebunny/crossref_metadata_2025 huggingface dataset:
Monoclonal Antibodies Specific for Members of the Genus Endotrypanum
Authors: LOPES ANGELA HAMPSHIRE C. S. , McMAHON‐PRATT DIANE
Published: May 2007

Twenty‐six monoclonal antibodies were produced against membrane‐enriched preparations of Endotrypanum schaudinni or Endotrypanum sp. promastigotes. Fifteen of these monoclonal antibodies (E1‐E15) reacted only with the standard strain of E. schaudinni, M6159. Monoclonal antibodies E16‐E26 were considered Endotrypanum specific; no cross reactivity was detected with any other genus of the family Trypanosomatidae (Leishmania, Trypanosoma, Leptomonas. Herpetomonas or Crithidia) by dot‐blot radioimmune assay. By indirect immunofluorescence assay, the antigens recognized by Endotrypanum specific monoclonal antibodies appear to be associated with the surface of the parasite. Based on Western blot analysis, 4 antigenic molecules ranging in molecular weight from 24 kD to 160 kD were identified by monoclonal antibodies specific for the strain of E. schaudinni, M6159. Monoclonal antibodies specific for the genus Endotrypanum identified an antigen of molecular weight 48 kD as well as a diffuse component migrating with an apparent molecular weight of 64–200 kD.
Development, Characterization, and Use of Monoclonal and Polyclonal Antibodies against the Myxosporean, Ceratomyxa shasta
Authors: BARTHOLOMEW J. L. , ROHOVEC J. S. , FRYER J. L.
Published: May 2007

Both monoclonal and polyclonal antisera were produced against Ceratomyxa shasta. Ascites containing trophozoites of the parasite was collected from infected fish and used as antigen for immunization of mice. The resulting monoclonal antibodies reacted specifically with trophozoite and sporoblast stages but did not react with C. shasta spores by either indirect fluorescent antibody techniques or in Western blots. This indicates that some C. shasta antigens are specific to certain life stages of the parasite. Polyclonal antiserum was produced in a rabbit by injecting a spore protein electro‐eluted from an SDS‐polyacrylamide gel. This antiserum reacted with both trophozoites and spores by indirect fluorescent antibody techniques and in Western blots. All antisera were tested for cross‐reactivity to trout white blood cells, a contaminant of the ascites, and to other myxosporea. Two monoclonal antibodies reacted with white blood cells and myxosporea of the genera Sphaerospora and Myxobilatus. One hybridoma produced antibodies of high specificity for C. shasta pre‐spore stages. This is the first report of a monoclonal antibody produced against a myxosporean parasite.
Coccidiosis in Sudanese Camels (Camelus dromedarius): 1 —First Record and Description of Eimeria spp. Harboured by Camels in the Eastern Region of Sudan
Authors: YAGOUB I. A.
Published: May 2007

ABSTRACT. Coccidial oocysts were detected in 40 (17.4%) out of 230 faecal samples obtained from camels in the Eastern Region of Sudan during June 1985‐June 1986. These oocysts were identified as Eimeria rajasthani, Eimeria dromedarii and Eimeria cameli. A detailed description of sporulated oocysts is given in this study and variations from previous authors’findings are discussed.
Binary Fission of Pneumocystis carinii Trophozoites Grown in Vitro
Authors: RICHARDSON J.D. , QUEENER S.F. , BARTLETT M. , SMITH J.
Published: May 2007

.Trophozoites grown in vitro were shown to undergo binary fission by transmission electron microscopy (TEM). Standard fixation with subsequent embedding in Spun‐ was employed using 3% glularaldehyde and 1% osmium tetroxide with 5% sucrose added to both fixatives and 0.1 M cacodylate buffer washes. Trophozoites were grown on WI‐38 cells in vitro. Trophozoites were found in various stages of fission. The dividing trophozoite has daughter cells that arc rounder than the pleomorphic, non‐dividing trophozoites. Tubular forms external to the dividing trophozoites were decreased in number, tubular forms when present were concentrated around the forming sepia. Nuclear material was sometimes, but not always, well defined in both daughter cells. There was no concentration of nuclear material at the poles. Vacuoles without membrane were present in the dividing forms. Separate nuclear regions were sometimes found in the dividing trophozoites. These observations suggest that binary fission does occur in culture; however, the significance of binary fission to the life cycle of Pneumocystis carinii (Pc) is not yet clear.
Analyses of Pneumocystis Fatty Acids
Authors: KANESHIRO EDNA S. , CUSHION MELANIET. , WALZER PETER D. , JAYASIMHULU KOKA
Published: May 2007

ABSTRACT
The major ester‐linked fatly acids of the total lipids extracted from Pneumocystis carinii isolated from the lungs of corticosteroid‐trealed rats were 16:0, 18:0, 18:1,18:2 and 20:4. Others detected included 14:0,16:1 and 22:4. The major sphingolipid fatty acids were 16:0, 18:0,22:0,24:0 and 24:1; others included 14:0,18:1, 20:0, 23:0, 24:2 and 26:0. The total lipid fatty acid compositions of preparations from appropriate lung controls were similar to those of the organism.
Microtubular Systems of Paramecium in Division: Pattern of Cytospindle Assembly
Authors: DELGADO PILAR , ROMERO M. ROSARIO , TORRES ANTONIO
Published: May 2007

The pattern of cytospindle assembly and the modifications of the microtubular cytoplasmic network during division of Paramecium are studied by means of indirect immunofluorescence. The assembly of cytospindle starts at two independent areas placed respectively around the proter's and opisthe's buccal overture. The moment of the microtubule bundles’appearance depends on their distance from the buccal opening, with those closest appearing 1st. The existence of microtubule organizing centers that act transiently during division of Paramecium is discussed.
Ultrastructure of Minchinia Sp. Spores from Shipworms (Teredo Spp.) in the Western North Atlantic, with a Discussion of Taxonomy of the Haplosporidiidae
Authors: McGOVERN ELIZABETH R. , BURRESON EUGENE M.
Published: May 2007

Electron microscopy of haplosporidan spores from Teredo navalis and T. furcifera revealed 4 distinct membrane‐bound extensions, 1 apical extension opposite the opercular hinge, 1 terminal and 2 opposing lateral extensions. These extensions were not continuous with the spore wall, but contained microtubule‐like structures and degrading epispore cytoplasm. No other known species in the family Haplosporidiidae is characterized by spores possessing four epispore extensions. There are currently two genera in this family, Minchinia and Haplosporidium. The genus Minchinia includes spores such as those of M. chitonis which bear two epispore cytoplasm extensions. Spores of the genus Haplosporidium have been characterized by spore wall derived filaments. A 3rd group of haplosporidan species with spores ornamented by wrappings have traditionally also been assigned to the genus Haplosporidium. Based on the presence of epispore cytoplasm extensions rather than spore wall filaments, the haplosporidan of Teredo spp. can be placed in the genus Minchinia.
Nutritional Studies on Acanthamoeba culbertsoni and Development of Chemically Defined Medium
Authors: SHUKLA O. P. , KAUL S. M. , MEHLOTRA R. K.
Published: May 2007

A chemically defined medium containing 11 amino acids, 3 vitamins, 6 inorganic salts and glucose, yielding maximum cell densities of 1.5‐2.5 × 107 cells/ml, has been developed for Acanthamoeba culbertsoni with a mean generation time (MGT) of 10 h. A medium containing six amino acids viz. arginine, methionine, leucine, isoleucine, valine and glycine along with other components could also support good albeit slower growth (MGT 27 h) of the amoeba. Acetate did not serve as a suitable carbon/energy source for A. culbertsoni. This organism bears close resemblance in its nutritional requirements to other Acanthamoeba especially A. polyphaga.
Conjugation Involving Dividing Cells of Tetrahymena thermophila
Authors: BLILEY MARY ANN , BELL CRAIG T. VAN
Published: May 2007

Feulgen‐stained preparations of mixtures of starved Tetrahymena thermophila cells of complementary mating types have revealed an atypical form of conjugation involving cells which have completed the nuclear events of cell division, but have not undergone cytokinesis. Both micronuclei in the dividing cells are induced to undergo meiosis, but in 21 of 23 cases, the anterior micronucleus was activated 1st, suggesting that the meiotic inducer is synthesized near the mating junction and diffuses posteriad. Despite the induction of two micronuclei, “triad” conjugants appear to regulate nuclear events so as to produce a normal outcome.
Ultrastructural Evidence for Bacterial Incorporation and Myxotrophy in the Photosynthetic Cryptomonad Chroomonas Pochmanni Huber‐Pestalozzi (Chyptomonadida)
Authors: KUGRENS PAUL , LEE ROBERT E.
Published: May 2007

Ultrastructural evidence indicates that bacteria are routinely incorporated into the CellsChroomonas Pochmanni. This strain has a specialized vacuole for capturing bacteria and retaining them in this vacuole. Bacteria appear to be drawn into the vacuole through a small opening which becomes occluded by membranes, completely enclosing the Bacteria. On rare occasions, ohter membrane components and intact ejectisomes also become incorporated into this vacuole. Bacteria‐like remnants in small vesicles, in other locations in the cell, suggest that bacteria are digested in these vesicles.
Changes in the Shape of Leishmania major Promastigotes in Response to Hexoses, Proline, and Hypo‐osmotic Stress
Authors: DARLING HOMAS N. , BLUM JOSEPH
Published: May 2007

Leishmania major promastigotes in late‐log phase are generally long and slender, and remain so during a 1 h incubation in buffer without exogenous substrate. When glucose, 2‐deoxyglucose, fructose, mannose, or proline are added, the cells become shorter and more rounded. The shape change in response to glucose is complete within 20 min and is reversible upon incubating the cells without substrate. Galactose, 3‐O‐methylglucose, 6‐deoxyglucose, sucrose, maltose, ribose, glycerol, alanine, glutamate or aspartate do not cause the shape change. Decreasing the osmolarity of the medium causes a rounding of the cells similar to that observed in the presence of glucose, and increasing the osmolarity inhibits the shape change in response to glucose. Inhibitors of glucose transport and 2nd messenger analogs do not affect the shape change.
Leishmania donovani: A Chemically Defined Medium Suitable for Cultivation and Cloning of Promastigotes and Transformation of Amastigotes to Promastigotes
Authors: KAR KALIPADA , MUKERJI KRISHNA , NASKAR KSHUDIRAM , BHATTACHARYA AMAL , GHOSH DILIP KUMAR
Published: May 2007

A chemically defined medium using commercially available α‐MEM supplemented with HEPES, L‐glutamine, D‐glucose, folic acid, D‐biotin and adenine supports the luxuriant growth and propagation of Leishmania donovani promastigotes. A peak parasite population of about 7.0 × 107/ml at stationary phase and a population doubling time of 11.4 h for high‐subpassage promastigotes were obtained. The medium was suitable for transformation of isolated amastigotes from infected hamster spleen. Promastigotes could be detected by culturing kala‐azar patients’bone‐marrow aspirate or spleen puncture material in this medium. Four out of six freshly transformed isolates gradually adapted and grew well in this medium. Macroscopic colonies appeared on agar plates prepared with the medium within 16–20 days after inoculation. The cloning efficiency was increased about five‐fold by glycerol supplementation.
On the Cytology and Taxonomic Position of Nudispora biformis N. G., N. Sp. (Microspora, Thelohaniidae), a Microsporidian Parasite of the Dragon Fly Coenagrion hastulatum in Sweden
Authors: LARSSON J. I.RONNY
Published: May 2007

The microsporidium Nudispora biformis n. g., n. sp., a parasite of a larva of the damsel fly Coenagrion hastulatum in Sweden, is described based on light microscopic and ultrastructural characteristics. Merogonial stages and sporonts are diplokaryotic. Sporogony comprises meiotic and mitotic divisions, and finally eight monokaryotic sporoblasts are released from a lobed plasmodium. Sporophorous vesicles are not formed. The monokaryotic spores are oval, measuring 1.4–1.8 × 2.8–3.4 μm in living condition. The thick spore wall has a layered exospore, with a median double‐layer. The polaroplast has two lamellar parts, with the closest packed lamellae anteriorly. The isofilar polar filament is arranged in 6 (to 7) coils in the posterior half of the spore. Laminar and tubular extracellular material of exospore construction is present in the proximity of sporogonial stages. In addition to normal spores teratological spores are produced. The microsporidium is compared to the microsporidia of the Odonata; its possible relations to the genus Pseudothelohania and to the Thelohania‐like microsporidia are discussed. The new genus is provisionally included in the family Thelohaniidae.
Buccal and Somatic Infraciliature of Lagynus elegans (Engelmann, 1862) Quennersted, 1867 (Ciliophora, Prostomatea): Remarks on its Systematic Position
Authors: SOLA ANA. I. , GUINEA ALMUDENA , LONGAS JOSE F. , FERNANDEZ‐GALIANO DIMAS
Published: May 2007

The somatic and buccal infraciliature of Lagynus elegans are described, and aspects of its division and conjugation are reported. Its somatic infraciliature is made up of 37–46 meridianal kineties composed of isolated kinetosomes that have thick and long kinetodesmal fibers. In the anterior zone of the cell, the circumoral infraciliature can be observed: it is composed of short, slightly oblique kinetal segments, which are formed of three kinetosomes each. The brosse of this species consists of 3 or 4 groups that possess 4 to 6 ciliated kinetosomes each; these kinetosomes lack kinetodesmal fibers. On the apical pole of the cell, surrounding the oral opening, a crown of nematodesmata is observed; these nematodesmata are connected to each other by a fibrillar structure. Taking into account these features, we propose that this genus be transferred from the order Prostomatida to a new family, Lagynidae, of the order Prorodontida.
The Regulation of Homopolar Doublets to Singlets in Glaucoma
Authors: SUHAMA MIKIO
Published: May 2007

ABSTRACT. In the ciliate Glaucoma scintillans, the process of transformation of unbalanced homopolar doublets to singlets was investigated. Cells were fixed 1–3 days after inoculation and impregnated with silver according to the Chatton‐Lwoff technique. The two oral apparatuses (OAs) approached each other partly due to a loss of ciliary rows in one of the two components (semicells) consisting of a doublet. The contractile vacuole pore (CVP) in the narrow semicell (sc1) was lost at an early stage of regulation, while the position of CVP in the broad semicell (sc2) shifted toward the right after the loss of sc1. The sc1 of 20 row‐intervals in breadth was a transition point above which the sc1 was able to persist for awhile, and beneath which it was actively lost. There was no evidence for an independent effect of sc2 on the transformation of doublets to singlets. In cell division, an additional reversed oral primordium (sOP) was formed in unbalanced doublets, usually within a narrow sc1 of 11–20 row‐intervals. The position of the sOP was generally 4–6 row‐intervals distant from the right side of the oral meridian (OM1) with the cell's left OA. Most of the doublets with an sOP lacked an oral primordium in the OM1. No mature triplet with 2 normal OAs and an abnormal OA was found in these preparations. The pathway of regulation, the movement of the CVP, and the formation of an sOP are discussed.
Neoglycoproteins as Carriers for Receptor‐Mediated Drug Targeting in the Treatment of Experimental Visceral Leishmaniasis
Authors: CHAKRABORTY PRASANTA , BHADURI AMAR N. , DAS PIJUSH K.
Published: May 2007

ABSTRACT. Methotrexate (MTX) coupled to mannosyl bovine serum albumin (BSA) was taken up efficiently through the mannosyl receptors present on macrophages. Binding experiments indicate that conjugation does not decrease the affinity of the neoglycoprotein for its cell surface receptor. The drug conjugate eliminated intracellular amastigotes of Leishmania donovani in mouse peritoneal macrophages about 100 times more efficiently than free drug on the basis of 50% inhibitory dose. Inhibitory effect of the conjugate was directly proportional to the density of sugar on the neoglycoprotein carrier. Colchicine and monensin, inhibitors of receptor‐mediated endocytosis, can prevent the leishmanicidal effect of the conjugate. Antileishmanial effect of the conjugate can be competitively inhibited by mannose‐BSA and mannan. In a murine model of experimental visceral leishmaniasis the drug conjugate reduced the spleen parasite burden by more than 85% in a 30‐day model whereas the same concentration of free drug caused little effect. These results indicate that MTX‐neoglycoprotein conjugate binds specifically to macrophages, and is internalized and degraded in lysosomes releasing the active drug to act on Leishmania parasites. These results also represent the potential for a general approach to intracellular targeting of clinical agents for macrophage‐associated disorders.
Minchinia teredinis N. Sp. (Balanosporida, Haplosporidiidae), a Parasite of Teredinid Shipworms
Authors: HILLMAN ROBERT E. , FORD SUSAN E. , HASKIN HAROLD H.
Published: May 2007

ABSTRACT. A new species of ascetosporan parasitizing tissues of woodboring mollusks of the genus Teredo, including T. navalis Linnaeus, T. furcifera von Martens, and T. bartschi Clapp, is described from light and transmission electron microscopical observations. The new species is assigned the name Minchinia teredinis sp. n. (Phylum Ascetospora, Class Stellatosporea, Order Balanosporida, Family Haplosporidiidae). Plasmodia, sporonts, sporocysts, and mature spores are found in all host tissues, but primarily in the gill. Spores are obovate, operculate, and characterized by four projections from the epispore membrane. The species is found from Long Island Sound to Virginia on the east coast of the United States. The parasite causes extensive damage to host tissues and is correlated with reductions in host populations.
Augmentation of Suppressed Antibody Responses in Mice During Experimental Chagas’Disease by T Helper Cells Activated in a Time‐Dependent Mode of Immunization
Authors: CHOROMANSKI LESZEK , KUHN RAYMOND E.
Published: May 2007

ABSTRACT. Mice infected with the protozoan parasite Trypanosoma cruzi, the causative agent of human Chagas’disease, develop immunosuppressed responses to heterologous antigens. Experiments were performed using infected mice in the acute stage of infection to assess immunoregulatory activities during induction of direct plaque‐forming cells (DPFC) to sheep erythrocytes (SRBC), hapten‐conjugated SRBC (TNP‐SRBC), and horse erythrocytes (TNP‐HRBC). Studies in vivo demonstrated that anti‐SRBC responses were best enhanced when T. cruz‐infected mice were injected with primed T cells derived from normal or infected mice immunized four days previously. The presence of enhancing capacities for DPFC responses by T cells from T. cruzi‐infected mice were also supported by experiments examining the hapten‐carrier effect. Preimmunization of infected mice with SRBC or HRBC four days before injection of hapten‐homologous (TNP‐SRBC or TNP‐HRBC) carrier resulted in markedly augmented anti‐hapten antibody responses. These results show that functional help provided by T cells activated during priming and exposed to a challenge dose of antigen (SRBC) in a time‐dependent mode can overcome the effect of immunosuppression in T. cruzi‐infected mice.
Constancy of Adenine Methylation in Tetrahymena Macronuclear DNA
Authors: KARRER KATHLEEN M. , STEIN‐GAVENS SUSAN
Published: May 2007

ABSTRACT. Macronuclear DNA from Tetrahymena was examined in order to determine whether the pattern of adenine methylation changed with the transcriptional activity of nearby genes. The DNA from growing, starved and conjugating cells was digested with six restriction enzymes which are sensitive to methylation of adenine within their recognition site. Southern blots of the restricted DNAs were probed with seven cDNA clones and one genomic clone which are homologous to polyA+ RNAs, whose transcriptional activity varies with the physiological state of the cell. One of the cDNA clones, BC11, had not been described previously. It hybridized to a 1.3kb transcript which was present in populations of starved and conjugating, but not in growing cells. On Southern blots of genomic DNA it hybridized to a complex pattern of bands which was highly polymorphic between the DNAs of closely related strains.

It was estimated that between 137 and 272 sites were assayed for changes in methylation, including at least 27 sites which were known to be methylated. No differences were seen in the size of restriction fragments from cells in different physiological states. The data suggested that the methylation pattern, which is determined during macronuclear development, does not vary with the physiological state of the cell.
Analysis of Pneumocystis carinii Cyst Wall. II. Sugar Composition
Authors: De STEFANO JAMIE A. , CUSHION MELANIE T. , PUVANESARAJAH V. , WALZER PETER D.
Published: May 2007

ABSTRACT. Pneumocystis carinii cysts are capable of resisting host defenses and antimicrobial drugs and are therefore thought to be responsible for relapses of P. carinii pneumonia in AIDS and other immunocompromised patients. The interaction of P. carinii with its host, and other P. carinii, might be mediated by molecules which form the outer surfaces of this organism. Carbohydrates are known to play many roles in cell‐cell adhesion, and have been detected on the surface of P. carinii by lectin labeling experiments. In this study P. carinii cyst wall material was obtained from Zymolyase treatment. Alditol acetate derivatives of neutral and amino sugars or trimethylsilyl derivatives of methyl glycosides were prepared from the monosaccharides released from the sample by acid hydrolysis. Analyses were done by a combination of gas chromatography and mass spectrometry. Glucose was found to be the major sugar constituent. Mannose and galactose were present in equal ratios. A lesser amount of N‐acetyl‐D‐glucosamine, and trace amounts of ribose and sialic acid were present in the cyst wall samples analyzed. These sugars may mediate P. carinii‐host interaction and play an important protective role by creating a permeability barrier around the cyst.
The Fine Structure of the Cortex of the Protist Protoopalina australis (Slopalinida, Opalinidae) from Litoria nasuta and Litoria inermis (Amphibia: Anura: Hylidae) in Queensland, Australia
Authors: PATTERSON DAVID J. , DELVINQUIER BEN L. J.
Published: May 2007

ABSTRACT. The ultrastructural appearance of cortical structures of Protoopilina australis is described. With respect to kinetosomal architecture and the supports of the surface folds, Protoopalina australis has an ultrastructural identity similar to other opalines. However, microfibrillar tracts and regular arrays of cortical vesicles—evident in Opalina and Cepedea—are absent from the binucleate genera. This new insight, combined with the recent discovery of a new genus (Protozelleriella) is used to revise our understanding of the evolution of slopalines and we favour a common origin for the multinucleate genera Opalina and Cepedea.
Morphology and Ultrastructure of Cryptobia eilatica n. sp. (Bodonidae: Kinetoplastida), an Ectoparasite from the Gills of Marine Fish
Authors: DIAMANT ARIEL
Published: May 2007

ABSTRACT. A marine kinetoplastid flagellate, Cryptobia eilatica n. sp., is described from the gills of cultured gilt‐head sea bream Sparus aurata L. and wild black‐spot sea bream Diplodus noct (Valenciennes) in the Red Sea. The trophozoite is elongated and lacks a contractile vacuole and undulating membrane. The body averages 13.5 × 4.1 μm, anterior flagellum 9.7 μm, and free portion of recurrent flagellum 15.2 μm. The ultrastructural features of the species exhibit great similarity to various previously studied Cryptobiids. Cryptobia eilatica trophozoites feed on bacteria, show a preference for the branc hial interlamellar crypts, and attach to the host epithelium by means of the recurrent flagellum. Neither penetration into the epithelial cells, nor any direct damage to host tissue was observed. Cryptobia eilatica inhabits a purely marine habitat, but its trophozoite tolerates salinities as low as 10 ppt.
Characterization of Mendelian and Non‐Mendelian Mutant Strains by Micronuclear Transplantation in Paramecium tetraurelia
Authors: KOBAYASHI SUMIKO , KOIZUMI SADAAKI
Published: May 2007

ABSTRACT. Mutant strain d48 and d12 cannot express serotype A. In d48, the A i‐antigen gene is present in the micronucleus, but not in the macronucleus. It has recently been shown that d12 contains the A gene in its micronucleus, but its macronucleus lacks the gene. Micronuclear transplantations into enucleated cells were performed to analyze those mutants. Reciprocal transplantation between wild type and d48 confirmed that d48 contains the A gene in the micronucleus and its cytoplasm is defective. Wild type 51 enucleated cells into which were transplanted d12 micronuclei could not express A. Amiccronucleate d12 cells into which were transplanted normal micronuclei from 51 or d48 showed no expression of A. These results show that even if the micronucleus of d12 contains the A gene, it must be abnormal, and its cytoplasm is also defective the same as d48. Genetic analysis showed that heterozygote of d12 and wild type 51 or d48 caused a cure of the cytoplasmic defect of d48 and d12 during the development of macronuclei.
Gametogenesis and Sporogonic Development of Haemogregarina balli (Apicomplexa: Adeleina: Haemogregarinidae) in the Leech Placobdella ornata
Authors: SIDDALL MARK E. , DESSER SHERWIN S.
Published: May 2007

ABSTRACT. The sexual stages and sporogonic development of Haemogregarina balli an apicomplexan blood parasite of snapping turtles, Chelydra serpentina were studied by electron microscopy for 30 days post feeding (PF). Gamonts were invested by an extracellular sheath which fused with intestinal microvilli. All stages of development were observed epicellularly within intestinal epithelial cells of the leech Placobdella ornata. Nuclear division in microgametogenesis was characterized by a trans‐nuclear cytoplasmic channel containing the spindle fibers. Basal bodies associated with nuclear division were unpaired with an atypical (8 + 0) microtubular conformation. Four aflagellate microgametes were formed. During fertilization, a single microgamete was enclosed in a pocket of a microgamont. The pocket was lined by a dense layer and underlying ER. In sporogony, nuclei were invested by a trilaminar pellicle as they divided, forming four anlagen. Each anlage divided by longitudinal binary fission forming eight sporozoites in mature oocysts. Sporozoites penetrated the intestinal epithelium by 27 days PF.
Enzyme Variation of Eimeria arizonensis from Peromyscus truei and P. boylii
Authors: WASH CONSTANCE D. , DUSZYNSKI DONALD W. , YATES TERRY L.
Published: May 2007

ABSTRACT. Cricetid rodents, Peromyscus truei and P. boylii, were inoculated with sporulated oocysts of Eimeria arizonensis collected from wild P. truei maintained in the lab. In P. truei the prepatent period was 4–5 days, the patent period was 9–11 days, and sporulated oocysts were 21.5 × 25.0 (20–23 × 24–26) μm with sporocysts 7.7 × 12.0 (6–8 × 10–13) pm. In P. boylii the prepatent period was 6–7 days, the patent period was 8–9 days, and sporulated oocysts were 20.1 × 23.2 (18–22 × 21–24) pm with sporocysts 6.8 × 10.0 (5–8 × 9–12) pm. Sporulated oocysts from both host species were used in direct side‐by‐side comparison of isozyme banding patterns using protein electrophoresis. The parasite has polytypic loci for leucine aminopeptidase (LAP), lactate dehydrogenase (LDH), and 6‐phosphogluconate dehydrogenase (6‐PGD). In oocysts from P. truei, LAP showed one band with fast migration and LDH and 6‐PGD each showed two bands, one with fast and one with slow migration. In oocysts from P. boylii, LAP and LDH each had one band with slow migration and 6‐PGD had one band with moderate migration. Oocysts of E. arizonensis collected from P. boylii were used to inoculate P. truei. The prepatent and patent periods, structural measurements, and isozyrne banding patterns of the resultant oocysts were the same as those from P. truei when inoculated with oocysts from P. truei.
Morphology and Morphogenesis of Two Species of the Genus Lembadion (Ciliophora, Oligohymenophora): Lembadion lucens and Lembadion bullinum
Authors: GUINEA ALMUDENA , SOLA ANA , LONGAS JOSE , FERNANDEZ‐GALIANO DIMAS
Published: May 2007

ABSTRACT. The morphology and morphogenesis of two species of the genus Lembadion, L. lucens and L. bullinum, are described. In both species, left and right ventral kineties converge behind the mouth forming a postoral suture. Buccal infraciliature is formed by one polykinety and two very close paroral kineties (inner and outer). During stomatogenesis, the new oral structures originate from the paroral kineties. The inner paroral kinety forms the new adoral polykinety and regenerates the outer paroral kinety of the proter, while the paroral kineties of the opisthe originate from the outer paroral kinety of the parental cell. Somatic proliferation starts before the stomatogenesis at the equatorial level of the cell, and extends towards the poles forming an equatorial band. Two large invariant zones, anterior and posterior, remain in the dividing cell. Moreover, the kinetodesmal fibers disappear in the proliferation band during the bipartition (fission) process.
Uronychia transfuga (O. F. Müller, 1786) Stein, 1859 (Ciliophora, Hypotrichia, Uronychiidae): Cortical Structure and Morphogenesis during Division
Authors: HILL BRUCE F.
Published: May 2007

Morphogenesis of cell division was investigated in Uronychia transfuga utilizing both light microscopy of living and stained specimens and SEM of preserved specimens. The cortical morphogenetic pattern of Uronychia is similar in several respects to that of the members of the family Euplotidae. These features include: the de novo development of the opisthe oral primordium in a subcortical pouch; the development of frontoventral and transverse cirri for both the proter and opisthe from 5 cirral primordia that form de novo within a single latitudinal developmental zone; and the absence of right marginal cirri. The members of the genus Uronychia also show a number of unique characteristics: development of a proter oral primordium that causes partial replacement of the parental adoral zone of oral polykinetids during development of the proter; a large oral membrane that is divided into a right and left component; large caudal cirri that bend to the left; and dorsal kineties comprised of closely set paired‐kinetosome kinetids. When compared to the other euplotid‐like ciliates, these unique features support the placement of the genus Uronychia in a separate family, Uronychiidae.
Effect of Extracellular Ions on Motility and Cell Entry in Toxoplasma gondii
Authors: ENDO TAKURO , YAGITA KENJI
Published: May 2007

Toxoplasma gondii tachyzoites were quiescent in mouse peritoneal fluid or in K2SO4 buffer at pH 8.2. They became consistently motile when K+ was replaced by other monovalent or divalent cations at a constant pH (pH = 8.2). They also became motile when Cl− was substituted for SO42‐. Nitrate or SCN−, can also be substituted for Cl− to a certain extent. Tachyzoites showed independent movement for more than 15 min in KCl, and for about 5 min in the other buffers at pH 8.2 after which they were exhausted and stopped. These tachyzoites could not then be further stimulated to motility by renewal of the suspension buffer. Infection of monolayer cells was demonstrated only with parasites which were motile during inoculation. The highest infectivity was thus obtained either with freshly collected tachyzoites or with those preincubated in K2SO4 buffer for 30 min at 37° C at alkaline pH and thus not yet exhausted for motility. Approximately 34 to 38% of these latter organisms were seen to enter cells when they were inoculated into cultures immediately after being resuspended in MEM for 30 min at 37° C. Conversely, those whose motility had been exhausted by the preincubation in buffers other than K2SO4, pH 8.2 could not enter monolayer cells. Additionally, parasites were unable to enter cells when inoculated into cultures in K2SO4 buffer at alkaline pH; instead they remained quiescent on the surface of the monolayer cells, suggesting that Toxoplasma enters the host cells by active invasion.
The Contribution of Ciliated Protozoa to Zooplankton Biomass in an Acidic, Subtropical Lake
Authors: BIENERT R. W. , BEAVER J. R. , CRISMAN T. L.
Published: May 2007

Ciliated protozoa accounted for up to 50% of the mean daily zooplankton biomass in McCloud Lake, a small (5 ha), oligotrophic, acidic (pH 4.7) lake in north‐central Florida. Food resources (algae and bacterioplankton) were limiting for crustacean and rotifer zooplankton during much of the year. Myxotrophic ciliates were a dominant component of the planktonic food web. Stentor niger, an uncommon species in the plankton of lakes, dominated the ciliate assemblage and usually comprised >90% of total ciliate biomass. Stentor niger always contained high densities of photosynthetic zoochlorellae and contributed an estimated 30% to the total autotrophic biomass.
Revision of the Family Lagenophryidae Bütschli, 1889 and Description of the Family Usconophryidae N. Fam. (Ciliophora, Peritricha)1
Authors: CLAMP JOHN C.
Published: May 2007

Ten species of lagenophryid peritrichs in three genera are redescribed or described for the first time. Based on this information, the family Lagenophryidae was found to consist of five genera: Lagenophrys, Paralagenophrys, Clistolagenophrys n. g., Setonophrys, and Operculigera. Lagenophryid genera differ in gross structure of the lorica aperture and the peristomial sphincter associated with it. Shape of the lorica and mode of attachment to the host are not generic characteristics in the Lagenophryidae. Differences in shape evolved within each of the three largest lagenophryid genera merely as adaptations for attachment to different parts of a host. Usconophrys, formerly in the Lagenophryidae, and Cyclodonta are assigned to the family Usconophryidae n. fam., which is characterized by possession of a lorica, lack of a closure apparatus operated by the peristomial sphincter, and possession of an operculariform peristome. Lagenophrys, Setonophrys, and Paralagenophrys appear to have evolved separately and convergently from ancestors within Operculigera. Lagenophryid lorica apertures consisting of opposing lips probably evolved as tight seals to prevent water loss when the host is temporarily out of water. The greater diversity and wider distribution of Lagenophrys compared with other lagenophryid genera may result from an advantage in recolonizing hosts conferred by second‐type division.
A Serum‐free, Partly Defined Medium, PDM‐805, for Axenic Cultivation of Entamoeba histolytica Schaudinn, 1903 and other Entamoeba
Authors: DIAMOND LOUIS S. , CUNNICK CAROL C.
Published: May 2007

We describe the first serum‐free, partly defined medium (PDM‐805) for cultivating the human enteric pathogen, Entamoeba histolytica, and the reptilian amebae E. barreti, E. invadens, and E. terrapinae. PDM‐805 was developed by the stepwise replacement of yeast extract, bovine serum, and a casein peptone digest in TYI‐S‐33, a medium widely used for the axenic cultivation of these parasites. The defined components include amino acids, carbohydrates, B vitamins, ascorbic acid, tocopherol, thioctic acid, nucleic acid precursors, trace metals, and phosphate buffers. The undefined components include a highly purified bovine serum albumin, a lipoprotein‐cholesterol solution from bovine serum, and a dialyzable, autoclavable, water‐soluble growth factor(s) having a molecular weight of less than 3,500 prepared from casein peptone. To date, studies on the growth requirements of E. histolytica, strain 200:NIH, show the following are essential for sustained multiplication of this ameba: iron, glucose, biotin, folic acid, niacinamide, pantothenate, pyridoxal, riboflavin, thiamine, cysteine, an ammonium moiety (in addition to that present in cysteine), bovine serum albumin, lipoprotein‐cholesterol, and casein peptone dialysate.
Observations with Hoechst Staining of Amitosis in Acanthamoeba castellanii
Authors: GICQUAUD CLAUDE , TREMBLAY NADINE
Published: May 2007

DNA staining with Hoechst 33258 allows us to visualize and to characterize amitotic division of Acanthamoeba castellanii in which the cell nucleus divides without DNA condensation and regular segregation of chromosomes. Amitosis involves several programmed and coordinated steps that exclude accidental cutting of the cell nucleus.
The Putative Mitochondrial Genome of Plasmodium falciparum
Authors: FEAGIN JEAN E. , GARDNER MALCOLM J. , WILLIAMSON DONALD H. , WILSON ROBERT J. M.
Published: May 2007

Intraerythrocytic stages of mammalian malarial parasites employ glycolysis for energy production but some aspects of mitochondrial function appear crucial to their survival since inhibitors of mitochondrial protein synthesis and electron transport have antimalarial effects. Investigations of the putative mitochondrial genome of Plasmodium falciparum have detected organellar rRNAs and tRNAs encoded by a 35 kb circular DNA. Some features of the organization and sequence of the rRNA genes are reminiscent of chloroplast DNAs. The 35 kb DNA also encodes open reading frames for proteins normally found in chloroplast but not mitochondrial genomes. An apparently unrelated 6 kb tandemly repeated element which encodes two mitochondrial protein coding genes and fragments of rRNA genes is also found in malarial parasites. The malarial mitochondrial genome thus appears quite unusual. Further investigations are expected to provide insights into the possible functional relationships between these molecules and perhaps their evolutionary history.
Enterocytozoon salmonis N. Sp.: An Intranuclear Microsporidium from Salmonid Fish
Authors: CHILMONCZYK STEFAN , COX WILLIAM T. , HEDRICK RONALD P.
Published: May 2007

The developmental stages of a recently described microsporidian from the nucleus of hematopoietic cells of salmonid fish were found to be unique among the Microsporida. All observed stages, including meronts, sporonts, and spores were in direct contact with the host cell nucleus (principally hematopoietic cells) of chinook salmon (Oncorhynchus tshawytscha). There is no par‐asitophorous vacuole and sporogony does not involve formation of a pansporoblastic membrane as with other members of the suborder Apansporoblastina. The extrusion apparatus differentiates prior to division of sporogonial plasmodia. The spores are ovoid (1 times 2 μm) and uninucleate, and possess a coiled polar tube with 8‐12 turns. Developmental stages of the salmonid microsporidian are similar to those described for Enterocytozoon bieneusi as found in the intestinal mucosa of human AIDS patients. However, the intranuclear development, different cell types, and host infected clearly separate the salmonid and human parasites. Accordingly, the intranuclear parasite of salmonids is given the name Enterocytozoon salmonis n. sp. within the suborder Apansporoblastina.
Coccidia of Brazilian Mammals: Eimeria Marajoensis N. Sp. (Apicomplexa: Eimeriidae) From the Anteater, Tamandua Tetradactyla (Xenarthra: Myrmecophagidae)
Authors: LAINSON RALPH , SHAW JEFFREY J.
Published: May 2007

ABSTRACT Feces from a juvenile specimen of the anteater Tamandua tetradactyla from Ponta de Pedras, Marajó, Pará, northern Brazil, contained three different coccidial oocysts: Eimeria tamanduae Lainson, 1968; E. corticulata Lainson & Shaw, 1990; and a third species previously unrecorded and described here as Eimeria marajoensis n. sp. Oocysts of the latter parasite are spherical to subspherical, 13.9 ± 1.5 times 13.4 ± 1.4 (11.1‐16.5 times 11.1‐16.5) μm, shape index (length/width) 1.0 (1.0‐1.2). the oocyst wall is a single, Colorless layer about 0.6‐1.0 μm thick with no striations or micropyle. There is no oocyst residuum, but a single, round, oval or irregularly shaped polar granule of about 0.75‐2.5 μm is consistently present. the sporocysts are broadly ellipsoidal, 7.1 ± 0.7 ± 5.3 ± 0.6 (6.0‐8.8 times 4.0‐5.7) μm, shape index 1.3 (1.2‐1.5), with a delicate wall bearing a minute stieda body. No sub‐stieda body was visible. the sporocyst residuum consists of some 10‐20 rounded granules, lying between the two slightly curved sporozoites which measure approximately 6.5 times 2.0 μm. Sporocyst refractile bodies were not discernablc.
Early Development of Eimeria Papillata (Apicomplexa: Eimeriidae) In the Mouse
Authors: STAFFORD STEPHANIE A. , SUNDERMANN CHRISTINE A.
Published: May 2007

ABSTRACT Early development of Eimeria papillata (Apicomplexa) in the mouse was evaluated using Nomarski interference‐contrast and brightfield microscopy. Sporozoite‐shaped meronts, which were motile and contained a large posterior refractile body and a smaller anterior refractile body, were observed entering and leaving host cells in the jejunum of an experimentally infected mouse at 26 h post inoculation (HPI). However, early developmental stages were not observed in tissue of the duodenum, ileum, cecum and colon. the mean length and width of these meronts (n = 20) were 12.0 μm and 3.7 μm, respectively. Spherical or subspherical meronts containing crescent‐shaped merozoites were observed at 36 HPI.
Enhanced Uptake and Metabolism of Riboflavin in Erythrocytes Infected with Plasmodium falciparum
Authors: DUTTA PURABI
Published: May 2007

Riboflavin deficiency inhibits the growth of malaria parasites both in vitro and in vivo in infected animals and humans. Although the precise mechanisms underlying this inhibition are unknown, they may involve enhanced requirements for riboflavin by parasites. To investigate this possibility, the rate of uptake of [14C]riboflavin and the biosynthesis of FMN and FAD from riboflavin were studied in infected (5–8% parasitemia) and uninfected human erythrocytes. All cells were incubated for 0–3 h at 37° C in phosphate buffered saline containing MgCl2, glucose, and [14C]riboflavin (2.5–7.5 μM). At hourly intervals, samples were removed, centrifuged, washed twice with cold buffer, and lysed before counting the radioactivity. The rate of in vitro biosynthesis of FMN and FAD from riboflavin in erythrocytes was measured by ion exchange chromatography and reverse isotope dilution techniques. Results showed that the rate of riboflavin uptake and the biosynthesis of FMN and FAD were enhanced in erythrocytes with parasitemia as compared with results in unparasitized erythrocytes. Riboflavin uptake in erythrocytes was proportional to the extent of parasitemia and especially to percent of schizonts present in erythrocytes. These studies indicate that the requirement for riboflavin may be greater in the parasite than in the host erythrocyte. This increased riboflavin requirement may be due to rapid multiplication, higher metabolic rate, and extreme vulnerability to oxidative stress of malaria parasites compared with that of host erythrocytes. The differential requirement of riboflavin by the host and the malaria parasite may hold important potential for developing new strategies for malaria chemotherapy.
Infraciliature, Morphogenesis and Life Cycle of Endosphaera terebrans (Suctoria, Tokophridae)
Authors: ESTEBAN GENOVEVA , TÉLLEZ CARMEN , MUÑOZ AMPARO
Published: May 2007

The morphology, infraciliature, and life cycle of Endosphaera terebrans, a suctorian endocommensal of peritrichs, have been studied with the aid of silver impregnation.

The life cycle of Endosphaera terebrans begins with infection of the host cell by a small larva. The swarmer has a pointed needle‐like cellular projection and two rings of cilia. The swarmer penetrates the peritrich, loses the cilia, and then matures into an adult. The infraciliature of the adult form has four rows of barren kinetosomes that lack kinetodesmal fibers. By endogenous budding, a migratory larva is produced that leaves the host cell through the peristomial disc and that can infect other peritrichs.
Differential DNA Amplification and Copy Number Control in the Hypotrichous Ciliate Euplotes crassus
Authors: BAIRD SCOTT E. , KLOBUTCHER LAWRENCE A.
Published: May 2007

ABSTRACT. During macronuclear development in hypotrichous ciliated protozoans, several thousand macronuclear DNA molecules are amplified several‐hundred fold. We investigated the regulation of this amplification by determining the copy numbers of three different macronuclear DNA molecules in the hypotrichous ciliate Euplotes crassus. Two of the macronuclear DNA molecules were present in approximately 1,000 copies per cell, while the third was present in approximately 6,500 copies per cell. These reiteration levels were achieved either during macronuclear development, or shortly thereafter, and were maintained during vegetative growth. The most abundant macronuclear DNA molecule is present as a single‐copy sequence in the micronuclear genome. Thus, its high copy number results from differential amplification. These results indicate that DNA amplification during macronuclear development is regulated individually for each macronuclear DNA molecule.
The Fine Structure of Secretion in Hyalophysa chattoni: Formation of the Attachment Peduncle and the Chitinous Phoretic Cyst Wall
Authors: LANDERS STEPHEN C.
Published: May 2007

ABSTRACT. The settling tomite stage of the apostome Hyalophysa chattoni secretes a phoretic cyst wall composed of chitin, mucopolysaccharides, and protein. Within 1 1/2 h after settling, an electron‐dense proteinaceous cyst layer (the outer layer) is formed from secretions originating at the base of the kineties and from the thick pellicular layer between the kineties. The inner cyst layer, composed primarily of chitin (acidic and neutral polysaccharides are also present), is secreted across the entire cell surface. Cyst wall formation is completed within 6 h. The fine structure of endocyst secretion resembles stages in the secretion of chitin by fungi, yeasts, and arthropods. A proteinaceous attachment peduncle is secreted to anchor the cell to a shrimp host and is formed by the release of electron‐dense secretory bodies from the cell's ventral surface.
Fine Structure of Triactinomyxon Early Stages and Sporogony: Myxosporean and Actinosporean Features Compared
Authors: LOM JIRI , DYKOVA IVA
Published: May 2007

ABSTRACT. The first ultrastructural study of the actinosporean genus Triactinomyxon was carried out on Triactinomyxon legeri from the intestinal epithelium of Tubifex tubifex. The developmental cycle starts with bi‐ and uninucleate cells. We propose that these cells may be an early proliferative phase of the cycle and may unite to give rise to the four‐cell stage, initiating pansporoblast formation. Valvogenic cells transform in the long stylus and anchor‐like projections of the spore. In the capsulogenic cells, the primordium of the polar capsules originates as a simple, dense, club‐shaped structure not observed in other actinosporeans. In all other respects, actinosporean ultrastructure follows more or less similar patterns. Comparison of actinosporean and myxosporean species gives evidence of considerable structural similarity, exemplified in both classes by the occurrence of cell junctions in their multicellular spores, identical polar capsules and their morphogenesis, cell‐in‐cell condition, pansporoblast formation, and presence of dense bodies (sporoplasmosomes) primarily in the sporoplasm. This unity of patterns speaks in favor of the postulated actinosporean‐myxosporean transformation, which warrants further study.