bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphology and Morphogenesis of Onychodromus quadricornutus n. sp. (Ciliophora, Hypotrichida), an Extraordinarily Large Ciliate with Dorsal Horns1
Authors: FOISSNER WILHELM , SCHLEGEL MARTIN , PRESCOTT DAVID M. 
Published: May 2007

ABSTRACTThe morphology and the morphogenesis of the freshwater hypotrich ciliate Onychodromus quadricornutus n. sp. have been investigated using living organisms, protargol impregnation, and scanning electron microscopy. Some preliminary and supplementary results about the morphogenesis of O. grandis and Laurentiella acuminata are included. The new species is unique among all described hypotrichs in having four dorsal horns, whose function is unknown. In addition, O. quadricornutus is probably the most voluminous hypotrich ciliate known (2 times 10‐6‐5 times 106μm3). Its morphogenetic pattern resembles the oxytrichids O. grandis and L. acuminata. The strongest apomorphic character, which unites these three species, is probably the multiple fragmentation of the dorsal primordia during morphogenesis. This fragmentation causes the characteristic high number and more or less irregular distribution of the dorsal kineties in the non‐dividing individuals.
New Eimeriid Coccidia from the Canarian Lizard, Gallotia galloti Oudart, 1839
Authors: MATUSCHKA F.‐R. , BANNERT B. 
Published: May 2007

ABSTRACTOne species of Eimeria and one species of Isospora have been discovered in several specimens of the Canarian lizard, Gallotia galloti, collected on Tenerife, Canary Islands, and are described herein as new. The oocysts of Eimeria gallotiae n. sp. are elongate‐ellipsoidal and measure 30.6 (29.1–32.6) by 16.0 (14.0–17.9) μm. Micropyle, oocyst residuum, and polar granule are absent. Oocysts each contain four ellipsoidal sporocysts measuring 14.6 (12.2–17.3) by 9.2 (8.2–11.2) μm. Sporocysts have sporocyst residuum but not a Stieda body. The majority of oocysts are fully sporulated when shed. Few oocysts are excreted unsporulated or in the beginning phase of sporulation. The oocysts of Isopora gallotiae n. sp. are spherical and 16.5 (15.3–17.6) μm in diameter. Micropyle, oocyst residuum, and polar granule are absent. Each oocyst has two lemon‐shaped sporocysts, 11.5 (10.2–12.2) by 7.3 (6.6–8.2) μm, which take up almost the entire space of the oocyst. A sporocyst residuum is present as well as a knob‐like Stieda body and a substieda body. Most oocysts are in the beginning phase of sporulation when excreted and have two spherical sporoblasts. Sporulation is completed within 24 to 28 h at 21 ± 2°C.
Experimental Vaccination of Chicks with Plasmodium gallinaceum Sporozoites. I. Circumsporozoite Proteins Are Expressed by Sporozoites Recovered from Both Salivary Glands and Midguts of Mosquitoes1
Authors: DAHER VALQUIRIA R. , KRETTLI ANTONIANA U. 
Published: May 2007

ABSTRACTImmunogenicity of Plasmodium gallinaceum Sporozoites for chicks and their in vitro reactivity with normal and specific immune sera were studied. Two sporozoite populations recovered from experimentally infected Aedes fluviatilis were used: sporozoites from salivary glands and sporozoites from midgut oocysts. Populations seven to nine days old of sporozoites recovered from salivary glands were infective for all chicks until the chicks were three weeks old; however, sporozoites recovered from midguts containing oocysts infected these chicks only if isolated on days 8–9, but not on day 7 after the mosquitoes' infective blood meal. Infectivity of the sporozoites was lost after exposure to ultraviolet (UV) light (30 min) or X‐rays (13 krad). Inactivated sporozoites from both sources proved highly immunogenic to chicks that were immunized by several intravenous or intramuscular injections. These parasites elicited a strong humoral immune response in the chicks, as measured by the circumsporozoite precipitation (CSP) reaction. The levels of the CSP antibodies were similar with sporozoites from both sources, there being no detectable differences in the percentage of reactive sporozoites or the intensity of the CSP reaction with sera containing antibodies to either sporozoites from salivary glands or sporozoites from oocysts. These results provide the first evidence that avian malaria sporozoites express the circumsporozoite protein that has been extensively characterized in mammalian malaria (rodent, simian, human sporozoites). Furthermore, we observed that the yields of sporozoites obtained from mosquito midguts, on days 8 and 9 of the P. gallinaceum infection, were at least twice as great as those obtained by salivary gland dissection, even 20 days after a blood meal. This is an advantage since obtaining the midguts is less tedious, as well as more efficient and faster.
Leptomonas ciliatorum n. sp. (Kinetoplastida, Trypanosomatidae) in the Macronucleus of a Hypotrichous Ciliate1
Authors: GÖRTZ HANS‐DIETER , DIECKMANN JOSEF 
Published: May 2007

ABSTRACTA leptomonad flagellate found in the macronucleus of the hypotrichous ciliate Paraholosticha sterkii carries out its whole life cycle there. The ciliates can divide, encyst, and excyst even when parasitized, and the flagellates are maintained throughout. Parasite‐free ciliates may be rapidly infected. The light‐ and electron‐microscopic structure of the flagellate resembles that of other leptomonads.
Inhibition of Multiplication in Acanthamoeba castellanii by Specific Inhibitors of Ornithine Decarboxylase1
Authors: KIM BYEONG G. , McCANN PETER P. , BYERS THOMAS J. 
Published: May 2007

ABSTRACTProliferation of Acanthamoeba castellanii (Neff strain) in either a broth medium or a defined medium was arrested by α‐monofluoromethyldehydroornithine (Δ‐MFMOme), α‐difluoromethylornithine (DFMO), and (R, R')‐δ‐methyl‐α‐acetylenic putrescine (MAP), three specific inhibitors of ornithine decarboxylase. Although all three inhibited the ameba enzyme, Δ‐MFMOme was the most effective inhibitor of multiplication. Growth inhibition was reversed by the addition of polyamines. The inhibitors did not induce differentiation by themselves although DFMO caused encystment when supplemented with CaC12 or MgSO4.
Factors Affecting Motility and Morphology of Cryptosporidium Sporozoites In Vitro1
Authors: WOODMANSEE DOUGLAS B. , POWELL EDWIN C. , POHLENZ JOACHIM F. L. , MOON HARLEY W. 
Published: May 2007

ABSTRACTIn vitro motility and morphology of Cryptosporidium sporozoites were examined in the presence of various solutions. Crude preparations of the bile salt, taurocholic acid, maintained both motility and morphology in a dose‐dependent manner. These effects appeared to be due to the taurocholic acid itself, and not simply due to pH variations, osmotic factors, or contaminants. Lysis of sporozoites was also observed and was found to be dependent on pH, with acidic conditions (pH < 6.2) triggering the lysis.
Fine Structure of a Silica‐Biomineralizing Testate Amoeba, Netzelia tuberculata1
Authors: ANDERSON O. ROGER 
Published: May 2007

ABSTRACTThe fine structure of the cytoplasm and the intracytoplasmic origin of siliceous granules and surrounding cement plaques used in constructing the shell wall of Netzelia tuberculata are described. These organisms construct their test from biogenic siliceous particles and sand grains or other foreign particles (including starch grains apparently from algal prey) coated with biogenic silica. The smooth surface texture of the grains, compared to those of other particle‐gathering testate amoebae, can be expalained by the deposition of a thin surface layer of silica on the foreign particles incorporated into the wall.
Eimeria tahamensis N. Sp. (Apicomplexa: Eimeriidae) from the Arabian Quail (Coturnix delegorguei arabica)1
Authors: Amoudi Mikky A. 
Published: May 2007

ABSTRACTEimeria tahamensis n. sp. is described from the harlequin quail (Coturnix delegorguei arabica) from Tahama, Saudi Arabia. The sporulated oocysts of E. tahamensis n. sp. are ellipsoid, 36.5–42 × 25.5–29 (41.2 ± 1.34 × 28.4 ± 0.81) μm, with a thick two‐layered wall and one polar granule but without a micropyle or an oocyst residuum. The sporocysts are ovoid, 14–16 × 9–11.5 (15.3 ± 0.7 × 10.8 ± 0.64) μm, with a knob‐like Stieda body and sporocyst residuum, but without a substiedal body. The sporozoites are often located transversely at the two ends of the sporocysts. The host bird belongs to the order Galliformes.
Receptor‐Mediated Endocytosis in the Bloodstream Form of Trypanosoma brucei1
Authors: Coppens I. , Opperdoes F. R. , Courtoy P. J. , Baudhuin P. 
Published: May 2007

ABSTRACTThe uptake of various host plasma proteins by the bloodstream form of Trypanosoma brucei was studied both biochemically, using radiolabeled proteins, and with the electron microscope, using colloidal gold particles as molecular tracers onto which plasma proteins had been adsorbed. Total plasma proteins and serum albumin were taken up by a mechanism of fluid endocytosis with low clearance (0.1 μ1 [mg cell protein]‐1 h‐1), while low‐density lipoprotein (LDL) and transferrin were taken up by a receptor‐mediated process with a clearance of two to three orders of magnitude higher than that of serum albumin. Binding prior to uptake of LDL and transferrin was saturable, depended on the presence of Ca2+, and the labeled ligand could be displaced by the homologous but not by heterologous protein. Binding of gold‐labeled proteins was seen only to the membrane of the flagellar pocket and not elsewhere on the plasma membrane. After 1 h of incubation at 30°C with gold‐labeled LDL and transferrin, labeled cellular structures represented respectively half and one‐third of the total volume of all single‐membrane bounded endocytotic and electron‐dense vacuoles within the cell.
Cryopreservation of Leucocytozoon caulleryi Sporozoites
Authors: MORII T. , MATSUI T. , IIJIMA T. , ABE N. , YOSHIZAWA A. , CHIKATSUNE M. , WATANABE M. 
Published: May 2007

ABSTRACTLeucocytozoon caulleryi sporozoites that had been stored at ‐ 196° C or ‐80° C for 6 or 12 months in Eagle's minimum essential medium or Medium 199 supplemented with 5% glycerol and 10% chicken serum showed infectivity to chickens. Glycerol at a concentration of 10% and dimethyl sulfoxide at 10% and 5% were found to be ineffective cryoprotective agents for the low temperature preservation of sporozoites. Sporozoites isolated from the intact females of Culicoides arakawae, which had been stored at ‐80° C for 6 or 12 months without cryoprotective agents, retained their infectivity. No differences were observed in the prepatent period, duration of parasitemia, and presence of serum‐soluble antigens between chickens infected with frozen sporozoites and those infected with fresh sporozoites.
Effects of Glycogen on Food Vacuole Formation in Parameium caudatum
Authors: FUKUSHIMA SHINICHI , OGAWA HIROSHI , NISHIKAWA TOMOYO , SASAGAWA SUKENARI 
Published: May 2007

ABSTRACTParamecium caudatum syngen 3 could not reproduce in the defined medium (DM) which had been developed for P. octaurelia stock 299, but we succeeded in culturing it in DM supplemented with glycogen. The number of food vacuoles which formed in 5 and 10 min at 25°C in the DM alone was greater in comparison with the DM supplemented with glycogen. These results showed that the high molecular weight substance which needed to be added to a defined medium for the cultivation of Paramecium did not always support cell reproduction by stimulating food vacuole formation.
Ribosome‐Inactivating Proteins from Plants Inhibit Ribosome Activity of Trypanosoma and Leishmania1
Authors: CENINI PIETRO , BOLOGNESI ANDREA , STIRPE FIORENZO 
Published: May 2007

ABSTRACTRibosomes from Trypanosoma brucei rhodesiense and from Leishmania infantum were isolated and optimal conditions for in vitro translation were established. The effect of ribosome‐inactivating proteins extracted from several plants was then assessed in order to identify those suitable for the preparation of immunotoxins against these organisms. Ribosomes from both species were inactivated by some ribosome‐inactivating proteins (dianthins, saporins, pokeweed antiviral proteins, and the ribosome‐inactivating chain of abrin). The similarity of the effects on the ribosomes from the two species examined indicates that ribosome‐inactivating proteins should also be effective in a similar way on ribosomes from other species of Trypanosoma and Leishmania.
A Survey of Lectin Binding in Paramecium1
Authors: ALLEN RICHARD D. , UENO MARILYNN S. , FOK AGNES K. 
Published: May 2007

ABSTRACTTo better understand the general distribution of glycoproteins and the distribution of specific glycoprotein‐bound sugar residues in Paramecium, a survey of the binding pattern of selected lectins was carried out in P. tetraurelia, P. caudatum, and P. multimicronucleatum. Lectins studied were concanavalin A (Con A), Griffonia simplicifolia agglutinins I and II (GS I and GS II), wheat germ agglutinin (WGA), Ulex europaeus (UEA I), peanut agglutinin (PNA), Ricinis communis toxin (RCA60) and agglutinin (RCA120), soybean agglutinin (SBA), Bauhinia purpurea agglutinin (BPA), Dolichos biflorus agglutinin (DBA), and Maclura pomifera agglutinin (MPA). Those giving the most distinctive patterns were Con A, GS II, WGA, UEA I, and PNA. No significant differences were found between the three species. Concanavalin A, a mannose/glucose‐binding lectin, diffusely labeled the cell surface and cytoplasm and, unexpectedly, the nuclear envelopes. Events of nuclear division, and nuclear size and number were thus revealed. Both WGA and GS II, which are N‐acetylglucosamine‐binding lectins, labeled trichocyst tips, the cell surface, and the oral region, revealing stages of stomatogenesis. The lectin WGA, in addition, labeled the compartments of the phagosome‐lysosome system. The lectin PNA, an N‐acetyl galactosamine/galactose‐binding protein, was very specific for digestive vacuoles. Finally, UEA I, a fucose‐binding lectin, brightly labeled trichocysts, both their tips and body outlines. We conclude that a judicious choice of lectins can be used to localize glycoproteins and specific sugar residues as well as to study certain events of nuclear division, cellular morphogenesis, trichocyst discharge, and events in the digestive cycle of Paramecium.
Three New Species of Eimeria (Apicomplexa: Eimeriidae) from Nerodia rhombifem (Serpentes: Colubridae) from Texas1
Authors: UPTON STEVE J. , McALLISTER CHRIS T. 
Published: May 2007

ABSTRACTThree new species of Eimeria (Apicomplexa: Eimeriidae) are described from the intestinal contents of Nerodia rhombifera (Serpentes: Colubridae) from Texas. Oocysts of Eimeria infirmus are irregular in shape, 11.6 (8.8–14.4) μm in diameter, with a smooth, thin wall that ruptures easily, releasing free sporocysts. A small polar granule is usually present, but a micropyle and oocyst residuum are absent. Sporocysts are bean‐shaped with one side flattened slightly, 9.1 times 5.0 (7.2–10.4 times 4.4–5.8) μm, with what may be a Stieda body consisting of a slight thickening of one end of the sporocyst. Each sporocyst contains a spherical or ellipsoid residuum and sporozoites, each with a single, posterior refractile body. Oocysts of Eimeria rhombifera are spherical or subspherical, 13.1 times 12.6 (12.0–14.4 times 11.2–14.4) μm, with a smooth, frail wall. A polar granule is present, but a micropyle and oocyst residuum are absent. Sporocysts are ovoid, 8.8 times 5.5 (8.0–9.6 times 5.0–6.0) μm, each with a Stieda body. Each sporocyst contains a spherical or subspherical residuum and sporozoites, each with a single posterior refractile body. Oocysts of Eimeria tenuis are ellipsoidal in shape, 17.2 times 10.8 (15.2–20.8 times 9.6–12.0) μm, with a smooth, thin wall. A polar granule and oocyst residuum are present, but a micropyle is absent. Sporocysts are elongate, 13.2 times 4.9(11.2–15.2 times 4.4–5.6) μm, each with a Stieda body consisting of a thickening of the sporocyst wall. Each sporocyst contains a spherical or subspherical residuum and sporozoites with anterior and posterior refractile bodies.
Fine Structure of the Shell Wall in the Soil Testate Amoeba Cyclopyxis kahli (Rhizopoda)1
Authors: OGDEN GOLIN G. 
Published: May 2007

ABSTRACTThe common soil testate amoeba, Cyclopyxis kahli, is capable of building a complete organic shell when grown in culture in the absence of agglutinate material. Such shells are morphologically similar to agglutinate shells except in the structure and diameter of the aperture. Chemical analysis of organic shells suggests that the main inorganic elements present are calcium and iron. Comparisons are made with similar analyses of organic shells from other agglutinate species. This is the first report of a significant change in shell architecture due to agglutinate material.
Eimeria ornata N. Sp. (Apicomplexa: Eimeriidae) from the Ornate Box Turtle, Terrapene ornata ornata (Reptilia: Testudines), in Texas
Authors: McALLISTER CHRIS T. , UPTON STEVE J. 
Published: May 2007

ABSTRACTEimeria ornata n. sp. is described from the feces of 6/16 (37.5%) ornate box turtles, Terrapene ornata ornata, in northcentral Texas. Endogenously sporulated oocysts are ellipsoid 17.9 × 15.7(16‐21 × 14‐18) μm, with a thin, single‐layered wall; shape index 1.14 (1.0‐1.3). A micropyle is absent but a polar granule was present in one third of the oocysts. An oocyst residuum was present, consisting of numerous small globules situated either in a distinct mass or scattered within the oocyst. The sporocysts are elongate, 11.1 × 5.4 (9‐13 × 5‐6) μm, with an indistinct Stieda body at 1 pole. A sporocyst residuum is present, consisting either as a compact mass or as scattered granules. The sporozoites are elongate, 9.5 × 2.0 (8‐12 × 2) μm, in situ, with spherical anterior and posterior refractile bodies. The new species is distinguished from the similar Eimeria carri Ernst & Forrester, 1973, from eastern box turtles, T. Carolina, by slight differences in oocyst morphology and endogenous sporulation.
Ultrastructure of Tachyzoites, Bradyzoites and Tissue Cysts of Neospora caninum
Authors: SPEER C. A. , DUBEY J. P. 
Published: May 2007

ABSTRACT. Dividing tachyzoites of Neospora caninum were 4x3 μm and had ultrastructural characteristics typical for the cyst‐forming coccidia. Unusual ultrastructural characteristics of fully‐formed tachyzoites included no micropores, 8–12 anterior and 4–6 posterior rhoptries, and a few posterior micronemes. Most tachyzoites were located free in the host cell cytoplasm; only a few occurred within a parasitophorous vacuole. Parasite multiplication appeared to be rapid because most organisms were in various stages of endodyogeny. Neural tissue cysts of N. caninum were 24.3 × 19.2 μm and contained 50–200 bradyzoites (7.3 × 1.5 μm), which lacked micropores. The cyst wall was 0.74–1.12 μm thick and consisted of the primary cyst wall (the parasitophorous vacuole membrane) and a thick granular layer with electron‐dense vesicles.
Binding of Lectins to Culture and Vector Forms of Trypanosoma rangeli Tejera, 1920 (Protozoa, Kinetoplastida) and to Structures of the Vector Gut
Authors: RUDIN W. , SCHWARZENBACH M. , HECKER H. 
Published: May 2007

ABSTRACTCulture forms of Trypanosoma rangeli could be agglutinated with Canavalia ensiformis (Con A) lectin and, less effectively with Pisum sativum agglutinin (PEA), at a concentration of 200 μg/ml. Ricinus communis agglutinin I (RCA I) agglutinated trypanosomes only if they were not previously washed with physiological Ringer's solution. Three other lectins did not react with the same parasite forms. Direct or indirect lectin‐gold labeling techniques were applied to LR‐White embedded thin sections of T. rangeli culture forms and to forms in the gut, hemolymph, and salivary glands of Rhodnius prolixus. Under these conditions, Con A was the only lectin out of 9 that bound to the surface of trypanosomes from culture and from the bug hemolymph. Con A did not react with any midgut or salivary gland forms. The preservation of the biological activity of the lectin‐gold complexes that did not bind to the parasite surface was confirmed by reactions with structures of the invertebrate host.
Mechanism of Long Slender (LS) to Short Stumpy (SS) Transformation in the African Trypanosomes
Authors: SEED JOHN R. , SECHELSKI JOHN B. 
Published: May 2007

ABSTRACTThe transformation of the long slender to the short stumpy stages of the African trypanosomes is an essential part of the trypanosome life cycle. Four possible mechanisms which could control this event have been investigated. It has been shown that (a) the dividing long slender to non‐dividing short stumpy transition is not a programmed event in the trypanosome life cycle; nor (b) would it appear to be initiated by some form of cell to cell contact inhibition of growth. In addition, evidence is presented which would suggest that (c) the transition is not started by the depletion of a critical growth nutrient from the environment during the growth of the trypanosomes. The last possibility (d) considered is that during trypanosome growth, a growth inhibitor‐short stumpy inducer accumulates in the trypanosomes’environment. Evidence is presented which shows that plasma from infected animals can inhibit the incorporation of thymidine by the trypanosomes. These data are consistent with the suggestion of an exogenous growth inhibitor accumulating during the infection.
Changes in Cell Surface Anionogenic Groups Induced by Propranolol in Herpetomonas muscarum muscarum
Authors: LOPES ANGELA HAMPSHIRE C. S. , FILHO FERNANDO COSTA E SILVA , ALVIANO CELUTA S. , JURKIEWICZ ARON , ANGLUSTER JAYME , DE SOUZA WANDERLEY 
Published: May 2007

ABSTRACTThe effects of propranolol (10−3 mM) on the surface anionic groups of Herpetomonas muscarum muscarum were analysed by cell electrophoresis, by ultrastructural cytochemistry and by identification of sialic acids using paper chromatography. Differentiation of H. muscarum muscarum induced by propranolol treatment caused a significant increase in the net negative surface charge. Binding of cationized ferritin (CF) and colloidal iron hydroxide particles was observed at the cell surface of both untreated and propranolol‐treated cells. In cells incubated in the presence of the drug the CF particles were distributed in all membrane regions. However, there were small areas where the particles were absent. In H. muscarum muscarum exposed to propranolol the density of residues of sialic acid per cell was higher, and the agglutinating activity with Sendai virus was more intense. However, the pattern of sialic acid, characterized by the presence of N‐acetylneuraminic acid derivative, was not modified upon cell interaction with the drug. Treatment of both control and propranolol‐treated protozoa with neuraminidase significantly reduced the surface charge. These findings suggest that sialic acid residues are the major anionogenic groups exposed on the surface of H. muscarum muscarum.
Marine Amoebae from Waters of Northwest Spain, with Comments on a Potentially Pathogenic Euryhaline Species
Authors: FERNANDEZ M‐CRISTINA ARIAS , CRESPO ESPERANZA PANIAGUA , MALLEN MARGARITA MARTI , ARES M. P. MONICA PENAS , CASAS M'LUISA CASTRO 
Published: May 2007

ABSTRACTOf 17 species of free‐living amoebae identified in various samples of salt water, only 1. Acanthamoeba polyphaga, is known to be a potential pathogen. While no deaths occurred when laboratory animals were inoculated with A. polyphaga to test for pathogenicity, the protozoa were present in the brain, liver and lungs of some but not all of the animals.