bluuebunny/crossref_metadata_2025 huggingface dataset:
Two New Species of Isospora from Indonesian Birds1
Authors: AMOUDI MIKKY A.
Published: May 2007

ABSTRACT. The following species are described from Indonesian birds: Isospora paddae n. sp. with oocysts 41.5–45.5 × 40.3–41.5 (44 ± 1.15 × 41.2 ± 0.38) and sporocysts 22.8–24.5 × 14.7–17 (24 ± 0.55 × 16.2 ± 0.81) from the Java sparrow, Padda oryzivora, and Isospora indonesianensis n. sp. with oocysts 39.3–43.6 × 37–40.8 (41.8 ± 1.3 × 39.6 ± 1.25) and sporocysts 25.6–28.4 × 15.2–18.5 (27.1 ± 1.05 × 16.8 ± 1.22) from the chestnut Munia, Lonchura malacca (L.). The host birds belong to the order Passerorida.
Reorganization in Amicronucleates with Defective Mouth of the Ciliate Pseudourostyla levis1
Authors: TAKAHASHI TADAO
Published: May 2007

ABSTRACT. The purpose of this work is to examine the reorganization process in amicronucleates with defective mouth of the multimicronuclear ciliate, Pseudourostyla levis. The amicronucleates were derived from fragments obtained by transection of normal micronucleates. The cell size of the amicronucleates was extremely unstable and varied from 57.5 to 276.3 μm long (n = 146), whereas the micronucleates kept rather stable cell lengths with a range from 162.5 to 266.3 μm (mean ± SD = 213.1 ± 19.6 μm, n = 206). The renucleates obtained by transplantation of a micronucleus to an amicronucleate returned to almost normal cell size (mean ± SD = 203.7 ± 16.5 μm long, n = 54). Under the usual culture conditions in the amicronucleate cell line, the number of abnormal cells with defective mouth rapidly increased, up to about 60%, until a stationary phase. Similarly, abnormal cells also appeared in micronucleates although the frequency was always less than 10%. The mean number of membranelles in the normal adoral zone of membranelles (AZM) was 82.6 ± 3.9 (±SD, n = 49) vs. 57.3 ± 7.9 (n = 81) in ciliates with defective mouths. The missing part of the AZM was always the anterior part of the lapel. Cells with defective mouth underwent reorganization (= physiological regeneration) under the usual culture conditions. During reorganization, the lapel part of the old AZM was transformed into a new collar part. The defective mouth was repaired through this developmental process. These results suggest that in P. levis the decrease of food supply often leads to the loss of a specific part of the AZM and that this membranellar loss is suppressed by the existence of micronuclei.
The Cellular Regulation of Vesicle Exocytosis by Entamoeba histolytica1,2
Authors: RAVDIN JONATHAN I. , MURPHY CHERYL F. , SCHLESINGER PAUL H.
Published: May 2007

ABSTRACT. We studied the cellular regulation of vesicle exocytosis by Entamoeba histolytica utilizing release of endocytosed 125iodine (125I) labeled tyrosine conjugated dextran; 125I‐dextran entered the acid pH vesicles of the amebae and was not degraded during these studies. Exocytosis was temperature dependent with 74%, 36%, 4%, and 0% of 125I‐dextran released after 120 min at 37°C, 31°C, 25°C, and 4°C, respectively (P < 0.01 for each). Exocytosis at 37°C was inhibited by cytochalasin D (10 μg/ml), EDTA (10 mM), or the putative intracellular calcium antagonist TMB‐8 (250 μM) (P < 0.01 for each at ≥ 60 min). Calcium ionophore A23187 (1 μM) enhanced exocytosis at 5 and 15 min (P < 0.01). Elevation of vesicle pH with NH4Cl (10 mM) had no effect on release of 125I‐dextran; phorbol myristate acetate (10−6 M) increased exocytosis by 46% at 30 min (P < 0.01). Centrifugation of amebae with target Chinese hamster ovary cells resulted in decreased 125I‐dextran release into the cell supernatant after 30 and 60 min at 37°C (by 40% and 42%, respectively, P < 0.01); release of 125I‐dextran returned to control values with addition of 1.0 g% galactose or GalNac but not with mannose or N‐acetyl‐D‐glucosamine. Amebic phagocytosis of serum‐exposed latex beads had no effect on release of dextran by amebae (n = 16). Exocytosis of acid pH vesicles by E. histolytica is temperature‐, microfilament‐, and calcium‐dependent, and stimulated by phorbol esters.
Comparative Analysis of the Fine Structure of Four Isolates of Trypanosomatids of the Genus Phytomonas1
Authors: ATTIAS M. , ROITMAN I. , CAMARGO E. P. , DOLLET M. , DE SOUZA W.
Published: May 2007

The fine structure of trypanosomatids from the plants Euphorbia hyssopifolia, E. characias, E. pinea, and Manihot esculenta, cultivated under axenic conditions, was compared. All parasites had a structural organization characteristic of members of the Trypanosomatidae. The organization of the membranes of the endoplasmic reticulum (ER) varied according to the isolate. In Phytomonas francai (isolated from M. esculenta), the ER cisternae form parallel rows. In Phytomonas sp. from E. characias, a para‐crystalline array of the ribosomes attached to the ER membranes was observed. The ER membranes found in Phytomonas sp. from E. pinea seemed to originate from the central portion of the protozoon, branching in all directions. The peroxisome‐like organelle (glycosome) found in Phytomonas sp. from E. hyssopifolia and E. characias occasionally showed an organized array. Taken together, the morphological observations make it possible to distinguish the four isolates of Phytomonas.
Ultrastructure of Two Types of First‐Generation Merozoites of Eimeria bovis1
Authors: SPEER C. A.
Published: May 2007

Eimeria bovis has two types of first‐generation merozoites with distinct ultrastructural characteristics. Type I merozoites were relatively large (X = 13.2 times 1.5 μm) and crescent‐shaped, contained numerous micronemes and amylopectin granules, had a posteriorly located nucleus and a conical‐shaped posterior tip, and were highly motile and capable of penetrating cultured cells. Type II merozoites were small (X = 5.9 times 0.9 μm) and spindle‐shaped, had a centrally‐located nucleus, few micronemes, few or no amylopectin granules, a dome‐shaped posterior tip and little motility, and appeared to be incapable of penetrating cultured cells. It is possible that these two types of merozoites have considerably different roles in the life cycle of E. bovis.
Cell Pairing during Mating in Tetrahymena: I. Does Phagocytosis or a Cell Surface Receptor Participate in Con A Block?1
Authors: CASCI ROBERT J. , HUFNAGEL LINDA A.
Published: May 2007

The lectin, Concanavalin A (Con A), inhibits cell pairing during mating in Tetrahymena and binds to the surface of pairing cells via receptors concentrated around the conjugation junction. Concanavalin A is also ingested in large amounts into food vacuoles. To dispel the possibility that Con A inhibits pairing via uptake into food vacuoles or through induction of food vacuole formation and to strengthen the idea that pairing is blocked through binding of Con A to cell surface receptors, we have conducted three types of experiments: 1) attempts to inhibit pairing by feeding with nutrients and with tantalum, a non‐nutritive reagent; 2) a temporal analysis of the presence of food vacuoles in mating cells fed with tantalum; and 3) analysis of the restoration of pairing following the addition of α‐methyl mannoside to cells previously treated with inhibitory concentrations of Con A. The results of these studies support the idea that Con A inhibits pairing by binding to receptors located on the cell surface and not by induction of or uptake into food vacuoles. We also present evidence that cells grown in an enriched proteose peptone medium are able to pair and undergo morphogenesis more readily than cells grown in 2% proteose peptone.
Complete Development of Caryospora bigenetica (Apicomplexa: Eimeriidae) In Vitro1
Authors: SUNDERMANN CHRISTINE A. , LINDSAY DAVID S. , TIBBS ROBERT E. , BAILEY MARK A.
Published: May 2007

The development of Caryospora bigenetica in vitro is described by light microscopy. Sporozoites from snake‐derived oocysts were purified and inoculated onto cultures of primary testicle cells of the cotton rat, cotton rat kidney cells, and human fetal lung cells. Intracellular sporozoites were observed one and two days postinoculation (DPI). Motile, extracellular first‐generation merozoites were present 3 DPI, and second‐generation merozoites were present 5 DPI. Mature gamonts were observed 9 DPI and developed into unsporulated oocysts by 10 DPI. Oocysts sporulated in vitro, and excystation was observed. Cells that were penetrated by in vitro‐produced sporozoites formed caryocysts by 16 DPI. To test infectivity of in vitro‐derived stages, merozoites were removed from cultured cells 5 DPI and inoculated intraperitoneally into a mouse; infection resulted. Sporulated oocysts removed from cell cultures 12 DPI produced facial swelling in an orally inoculated cotton rat.
Fine Structure of Silica Deposition and the Origin of Shell Components in a Testate Amoeba Netzelia tuberculata1
Authors: ANDERSON O. ROGER
Published: May 2007

ABSTRACT Netzelia tuberculata secretes a test composed of siliceous particles cemented together by organic plaques forming a single‐layered spheroidal shell. The siliceous particles are produced within cytoplasmic vacuoles by three mechanisms: 1) synthesis de novo by deposition of the silica on a matrix; 2) deposition of silica on particles remaining in digestive vacuoles, including starch grains and undigested walls of yeast cells; and 3) secretion of silica as a hollow sphere at the periphery of vacuoles enclosed by the silicasecreting membrane. The silicalemma (silica‐secreting membrane) originates as fibril‐containing vesicles (GFV) secreted by the Golgi body. Fusion of these vesicles with membranes surrounding digestive vacuoles or with membranes surrounding specialized vacuoles containing a silica‐binding matrix apparently converts the vacuole into a silica‐depositing organelle. Small spherules of silica occur on the vacuolar side of the membrane surrounding the developing test granules, marking the presence of silicalemma activity. These colloidal spherules become aggregated into larger spherules that condense to form the siliceous surface of the developing test particle. Other Golgi vesicles, designated Golgi plaque vesicles (GPV), produce the organic plaques that are deposited among the siliceous particles at the periphery of the cell during new test construction during cell division. The fine structure of the GFV and GPV and their role in test wall deposition are discussed in relation to other silica‐biomineralizing protozoa, including radiolaria.
Ultrastructural Features of the Oral Region of Amicronucleate Paramecium tetraurelia in Autogamy1
Authors: JURAND ARTHUR , NG STEPHEN F.
Published: May 2007

ABSTRACT Amicronucleate Paramecium tetraurelia fails to develop an oral apparatus but resorbs the pre‐existing one in the sexual cycle. Previous cytological studies have revealed the presence of a shallow, oral depression with a few scattered basal bodies after autogamy or conjugation. The present ultrastructural study of the ectoplasm beneath the oral depression revealed only the presence of a disorganized filamentous reticulum and small blocks of cytopharyngeal ribbons. In addition, beneath the oral depression, a large number of discoidal vesicles were found, similar to but larger in diameter than those normally associated with the cytopharynx of vegetative cells. The oral structures found in amicronucleates in autogamy might be remnants of the pre‐existing oral apparatus, but the possibility that they were newly developed was not excluded. The morphogenetic interest of these structures was discussed. It is evident that amicronucleates in autogamy do not develop an extensive oral ultrastructural organization.
Antigenic Heterogeneity in the 115,000 Mr Major Surface Antigen of Trichomonas vaginalis1
Authors: TORIAN BRUCE E. , CONNELLY ROBERTA J. , BARNES ROBERT C. , KENNY GEORGE E.
Published: May 2007

ABSTRACT The 115,000‐molecular‐weight antigen of Trichomonas vaginalis was characterized using monoclonal antibodies developed to three different strains of T. vaginalis and one strain of Tritrichomonas foetus. The antigen was found to be present on all strains or isolates of T. vaginalis examined and was demonstrated to be located on the external surface plasma membrane by agglutination assays and complement‐mediated lysis assays. Characteristics of the antigen were assessed with a proteolytic enzyme and periodate oxidation. Periodate treatment of whole T. vaginalis abrogated binding for eight antibodies while use of pronase‐treated antigen resulted in loss of antibody binding for two different antibodies. Screening of 19 axenized clinical isolates of T. vaginalis and one strain each of T. foetus and Giardia lamblia with type‐specific antibodies delineated three major groups of T. vaginalis based on antigenic specificities (epitope distributions) within the 115,000‐molecular‐weight antigen. In addition, one epitope of the 115,000‐molecular‐weight antigen was found only on the immunizing strain. Two epitopes were present on all T. vaginalis isolates as well as T. foetus and G. lamblia. One epitope was common to all T. vaginalis except one. A minimum of six different epitopes of the 115,000‐molecular‐weight antigen were identified. Antigens purified with type‐specific or “common” monoclonal antibodies shared the same partial peptide maps demonstrating relatedness.
Secretory Hydrolases of Entamoeba histolytica1
Authors: MÜLLER FRIEDRICH‐WILHELM , FRANZ ALFRED , WERRIES ECKHARD
Published: May 2007

ABSTRACT Cells of Entamoeba histolytica grown over a period of four days contained NADP+‐dependent alcohol dehydrogenase exclusively inside the cells. No activity of this enzyme could be found in the growth medium after harvesting the cells. Under the same conditions, acid phosphatase, β‐N‐acetylglucosaminidase, esterase, α‐glucosidase, and different amylases of the parasite were found both inside the cells and in the medium. The activities present in the cell homogenate and in the medium before and after growth of the amoebas were partially separated by gel filtration on Sephadex G150 and G75, respectively. The comparison of the elution diagrams revealed that NADP+‐dependent alcohol dehydrogenase, acid phosphatase, esterase, and amylases occurred as multiple forms inside the cells. These activities, as well as β‐N‐acetylglucosaminidase and α‐glucosidase, were released into the extracellular environment to a different degree. The enzymes originating from the parasite were identified and distinguished from those of the ingredients of the growth medium according to their molecular mass and pH optimum. Furthermore, the amoebic origin of the secreted enzymes was shown on the basis of their inhibition by antibodies prepared against the supernatant fraction of the homogenate.
Trimyema compressum Lackey, 1925: Morphology, Morphogenesis and Systematic Implications1
Authors: SERRANO SUSANA , MARTÍN‐GONZÁLEZ ANA , FERNÁNDEZ‐GALIANO DIMAS
Published: May 2007

ABSTRACT Trimyema compressum is a species included in the family Trimyemidae with the single genus Trimyema. This species has 50–60 somatic kinetics and three rows of kinetosomes surrounding the oral cavity. Two isolated groups of kinetosomes can also be observed on the right side of the oral region. The morphogenesis of bipartition is telokinetal; all the new infraciliary structures of the opisthe come from the longitudinal and postero‐anterior proliferation of the last kinetosome of all the somatic kinetics. In the proter there is a reorganization of the oral infraciliature.

As a result of our observations, we suggest that the systematic position of the genus Trimyema be changed from the subclass Vestibulifera to the subclass Gymnostomata. We also consider that this genus must be included in the suborder Trimyemina Jankowski, 1980.
Changes in the Cytoplasmic Elements of Cultured Cells Infected with Eimeria vermiformis Sporozoites
Authors: ADAMS JOHN H. , BUSHELL GILLIAN R.
Published: May 2007

Epithelial‐type (PK‐15) and fibroblast‐type (MDBK) mammalian cell cultures were inoculated with purified Eimeria vermiformis sporozoites. Matched samples from 0 to 93 h after inoculation (HAI) were processed for electron microscopy; half of the sample preparations were extracted with non‐ionic detergent prior to fixation. Specimens were examined by both transmission and scanning electron microscopy. Numerous sporozoites were attached to the cultured cells from 2 to 93 HAI, usually near the cell periphery. Some host cell microvilli extended up and appeared attached to the sporozoites. Sporozoites fixed during the penetration process were markedly constricted at the site of entry; however, no noticeable changes occurred in the host cell membrane or surface microvilli during sporozoite invasion or in sporozoite‐infected cells. In cells extracted with 1% Triton X‐100, the host cytoskeleton was progressively reorganized about the parasites but changes were limited to the immediate area of the sporozoite. Around resident sporozoites, the cytoskeleton became less dense but also more ordered, which contrasted with adjacent cell areas. Cytoskeletal elements passed both over and under the parasites. The appearance of the cytoskeleton suggested that the host cell formed a loose, basket‐like net of cytoskeletal elements about the parasite.
Ichthyophthirius multifiliis Has Membrane‐Associated Immobilization Antigens
Authors: DICKERSON H. W. , CLARK T. G. , FINDLY R. C.
Published: May 2007

Sera from fish that survive infections with the ciliated protozoon, Ichthyophthirius multifiliis, immobilize the parasite in vitro. In order to identify ceil surface antigens involved in the immobilization response, integral membrane proteins were extracted from tomites with Triton X‐l14 and used to immunize rabbits. The rabbit antisera immobilized the parasite in vitro and antigens were localized to cell and ciliary plasma membranes by indirect immunofluorescent microscopy. The membrane protein fractions from both whole cells and tomite cilia were characterized by 1 ‐ and 2‐dimensiona! SDS‐PAGE. A 43,000‐dalton (D) glycoprotein with an isoelectric point of 7.0 is the predominant protein in these fractions, comprising 12% and 60% of the total protein of whole cell and ciliary membranes, respectively. Western blot analysis of ciliary proteins with immune rabbit sera indicated that the 43,000‐D glycoprotein is the principal antigen.
Cytochemical Localization of Plasma Membrane Enzyme Markers During Interiorization of Tachyzoites of Toxoplasma gondii by Macrophages
Authors: CARVALHO LAÍSS DE , SOUZA WANDERLEY DE
Published: May 2007

The enzyme activity of Mg‐ATPase, Na+‐K+‐ATPase, 5′‐nucleotidase and NAD(P)H‐oxidase was cytochemically detected at the ultrastructural level in mouse peritoneal macrophages infected with untreated and with specific antibody‐coated Toxoplasma gondii tachyzoites. The Mg++‐ATPase and 5′‐nucleotidase were distributed throughout the macrophages’plasma membrane but were not observed in the membrane lining endocytic vacuoles containing ingested parasites; however, Na+‐K+‐ATPase activity was detected in the macrophages’plasma membrane as well as in the parasitophorous vacuoles that contained untreated or specific antibody‐coated parasites. Reaction product, indicative of NAD(P)H‐oxidase, was detected in the parasitophorous vacuoles that contained only‐specific antibody‐coated parasites.
The Release of Holospora obtusa from Paramecium caudatum Observed with a New Device for Extended In Vivo Microscopy
Authors: WIEMANN M.
Published: May 2007

The macronudeus‐specilic bacterium Holospora obtusa is released from its host cell Paramecium caudatum generally after a preceding cell division. Before division, most infectious forms of the bacteria can be found in a connecting strand of the dividing macronucleus. This connecting strand is deformed and finally expelled as a whole from the daughter cells. This process was observed and photographed with a simple device allowing observations for a long lime under a microscope without damage to the living cells. Key words. Bacterium, cytoproct, defecation, infection, macronucleus, symbiosis.
The Nuclear Envelope of Amoeba proteus During Mitosis as Studied With a Monoclonal Antibody Against a Membrane‐Associated Protein
Authors: KIM CHONG H. , CHOI EUI Y. , JEON KWANG W.
Published: May 2007

. The behavior of nuclear envelopes during mitosis in Amoeba proteus was studied by means of indirect immunofluo‐rescence staining using a monoclonal antibody against a 220‐kD membrane‐associated protein of amoebae in conjunction with DAPI staining of chromatin. The antibody selectively recognized antigens on nuclear envelopes during interphase but did not react with the nuclear membranes during mitosis until after cytokinesis had been completed. Thus, it appeared that the membrane‐associated protein reacting with the monoclonal antibody and normally present on the nuclear membranes was absent from fragmented nuclear membranes or nuclear membranes that were continuous but did not have the honey‐comb lamina. The findings suggested that the 220‐kD nuclear‐membrane protein may be involved in the dissolution and reformation of the honey‐comb lamina during mitosis in amoebae.
Redescription of Flagellar Arrangement in the Duck Intestinal Flagellate, Cochlosoma anatis and Description of a New Species, Cochlosoma soricis N. Sp. from Shrews
Authors: WATKINS RAYCHEL A. , O'DELL WILLIAM D. , PINTER AELITA J.
Published: May 2007

Cochlosoma anatis Kotlán (Zoomastigophorea, Retortamonadida, Cochlosomidae), isolated from the large intestines of domestic Rouen ducks, and Cochlosoma soricis n. sp., isolated from the small intestines of shrews, were observed by light and scanning electron microscopy. In both organisms, a single flagellum inserted on the dorsal surface at the same level as the insertion of 4 other flagella on the ventral surface. The 4 ventro‐lateral flagella emerged from the left side of the anterior attachment disk below the margin and just above the lateral groove which extended the length of the organism. A 6th flagellum emerged from the margin of the attachment disk. The proximal ends of the flagella formed a bundle with the distal ends becoming unraveled like a rope. During motility, the bundle portion extended straight out from the cell and the free ends of the flagella produced a whipping motion. In C. anatis, the dorsal surface was covered with knob‐like lumps and small pits and the cells had an axostyle that emerged slightly to the right of the midline in the posterior 1/3 of the body. The axostylar tip was shorter and thicker than the flagella and in most cells it also had an irregular, knobby appearance. The irregular cell surface and axostyle were absent from C. soricis. The margin of the attachment disk curved toward the center and terminated in C. anatis as a straight edge while in C. soricis it continued as a spiral. Indentations in the mucosal brush border similar to those produced by Giardia, but distinctly belonging to Cochlosoma, were interpreted as points of attachment to the host.
Culture and Generic Identification of Trypanosomatids of Phytophagous Hemiptera in Brazil
Authors: SBRAVATE CLIZETE , CAMPANER MARTA , CAMARGO LUIS E. A. , CONCHON IVETE , TEIXEIRA MARTA M. G. , CAMARGO E. PLESSMANN
Published: May 2007

Among the 372 phytophagous Hemiptera examined, 133 insects of 28 species (Coreidae 18, Pentatomidae 7, Pyrrhocoridae 2, Lygaeidae 1) were infected with trypanosomatids. Gut infections only were found in 68.4%, gut and salivary gland infections in 29.3% and salivary infections alone in 2.3%. Fifty‐one cultures were isolated from 38 insects. Cultures were characterized by assay of certain ornithinc‐arginine metabolism enzymes and by indirect immunofluorescence against monoclonal antibodies specific for Phytomonas spp. Ten cultures were identified as either Crithidia or Leptomonas. Twenty‐one promastigote cultures had an enzyme pattern hitherto recorded only for Leishmania and 16 cultures were identified as Phytomonas.
Antigenic Reactivity of a Monoclonal Antibody Against Amoeba proteus Actin
Authors: AHN TAE I. , JEON KWANG W.
Published: May 2007

The reactivity of a monoclonal antibody against actin of Amoeba proteus with actins from other sources was examined. The monoclonal antibody cross‐reacted with actins from vertebrate muscles, human erythrocytes, and Acanthamoeba castellanii, but it did not react with Naegleria gruberi actin. The amoeba actin was resolved into 3 bands with isoeletric points of 5.96, 6.03 and 6.10 in electrofocusing gels and they corresponded to 3 peptide spots reacting with the antibody on 2‐dimensional immunoblots.
A Thermostable Acid α‐Glucosidase from Tetrahymena thermophila: Purification and Characterization
Authors: BANNO YOSHIKO , SASAKI NOBORU , YOSHINO TIKAKO , MOCHIZUKI JUN‐ICHIROH , HIRATA HAJIME , NOZAWA YOSHINORI
Published: May 2007

An acid α‐glucosidase (EC 3.2.1.20) was purified to homogeneity from the culture medium of Tetrahymena thermophila CU 399. Its general molecular, catalytic and immunological properties were compared to those of the T. pyriformis W enzyme. The enzyme from T. thermophila was a 105‐kD monomer and the N‐terminus (25 amino acid residues) displayed some homology with that of T. pyriformis enzyme. The purified enzyme was most active at 56° C and showed resistance to thermal inactivation. The acid α‐glucosidase appears to have α‐1,6‐glucosidase as well as α‐1,4‐glucosidase activity. The Km values determined with p‐nitrophenyl‐α‐glucopyranoside, maltose, isomaltose and glycogen were 0.7 mM, 2.5 mM, 28.5 mM and 18.5 mg/ml, respectively. The enzyme was antigenically distinct from T. pyriformis acid α‐glucosidase.
Two New Species of Isospora from the Desert Skink (Chalchides ocellatus) from the Egyptian Desert
Authors: AMOUDI MIKKY A.
Published: May 2007

Isospora chalchidis n. sp. and Isospora eimanae n. sp. were isolated from the desert skink, Chalchides ocellatus, order Squamata, from Egypt. Sporulated oocysts of I. chalchidis n. sp. were spheroidal 19 × 19 (18–20.5 × 18–20.5) μm with a 2–layered walled. Oocysts lacked a micropyle and residuum and few polar granules were present. Sporocysts were lemon‐shaped 12.2 × 6.5 (9.5–13 × 5–8) μm with a Stieda body and sporocyst residuum but without a substiedal body. Isospora eimanae n. sp. were spheroidal 18.5 × 18.5 (17–19.5 × 17–19.5) μm with a 2–layered wall. There were oocysts without residuum or polar granule, but with small micropyle at 1 end. Sporocysts were ovoid 12 × 8.5(11–13 × 7.5–9) μm with a small Stieda body and sporocyst residuum but without a substiedal body.
Amplification of a New Region of DNA in an Unselected Laboratory Stock of L. tarentolae: The T Region
Authors: PETRILLO‐PEIXOTO MARIA L. , BEVERLEY STEPHEN M.
Published: May 2007

A new DNA amplification is described from an isolate of the lizard parasite Leishmania tarentolae. This DNA is present in up to 50 copies in the Trager line of this species and present but not amplified in all other lines tested. This amplification has been named the T amplification (for Tarentolae/Trager). Restriction enzyme digestion and electrophoresis of total DNA reveal amplified fragments totalling 19 kb following staining with ethidium bromide, a finding confirmed by the use of specific hybridization probes. Much of the amplified T DNA occurs as extra‐chromosomal circular molecules. No cross‐hybridization was observed between the T region and other amplified DNA of Leishmania, or the maxicircle of L. tarentolae, nor was resistance to methotrexate, chloroquine or primaquine detected in the T‐amplified line. Combined with our previous results showing H region amplification in 2 other unselected lab stocks, these data demonstrate the prevalence of apparently spontaneous gene amplifications in L. tarentolae.
Monoclonal Antibodies for the Identification of Trypanosomatids of the Genus Phytomonas
Authors: TEIXEIRA MARTA M. G. , CAMARGO E. PLESSMANN
Published: May 2007

Monoclonal antibodies have been produced against culture forms of Phytomonas francai and Phytomonas serpens parasites, respectively, in cassava roots and tomato fruits. These monoclonal antibodies have been tested against 5 other Phytomonas spp. isolated from plants and 14 species of trypanosomatids of various genera. Monoclonal antibodies were found to react exclusively with Phytomonas spp., always giving negative results with other trypanosomatid genera. Thus, these monoclonal antibodies seem to be an effective tool for the identification of phytomonads among insect trypanosomatids.
Life Cycle and Culturing of Phytomonas serpens (Gibbs), a Trypanosomatid Parasite of Tomatoes
Authors: JANKEVICIUS J. VITOR , JANKEVfCIUS SHIDUCA I. , CAMPANER MARTA , CONCHON IVETE , MAEDA LUCIO A. , TELXEIRA MARTA M. G. , FREYMULLER EDNA , CAMARGO E. PLESSMANN
Published: May 2007

Pure cultures of a trypanosomatid isolated from tomato fruits infected laboratory‐raised tomatoes and nymphs of the hemipieran coreid Phthia picta. The flagellate could be transmitted back and forth from tomatoes to insects. Light and electron microscopy studies were done on culture, tomato and insect forms. Examination of enzymes of the ornithine‐arginine metabolism revealed absence of arginase and presence of arginine deiminase and citrulline hydrolase. Monoclonal antibodies specific for Phytomonas spp. reacted positively with tomato and insect forms. Endonuclease digestion of the k‐DNA of various Phytomonas spp. revealed a unique, distinctive pattern for the tomato flagellate. This flagellate thus seems to constitute a separate species of Phytomonas which we now call Phytomonas serpens (Gibbs).
Somatic Infraciliature in the Haptorid Ciliate Homalozoon vermiculare (Kinetophragminophora, Gymnostomata) Ditransversalia N. Subcl. and Phylogenetic Implications
Authors: LEIPE DETLEV D. , HAUSMANN KLAUS
Published: May 2007

The ultrastructure of the cortex of Homalozoon vermiculare is described. The ventral side bears 13–15 iongitudinal kineties composed of monokinetids. On the dorsal surface, there are 3 kineties, 2 of which are composed of dikinetids in the anteriormost part of the cell. Consequently there exist 3 different kinds of kinetids within the somatic cortex: 1) The monokinetids on the ventral side are associated with a kinctodesmal fibril, 2 transverse microtubular ribbons and 7 postciliary microtubules in a double‐row configuration; 2) The monokinetids on the dorsal side are very similar but they are associated with just 3 very ‘short postciliary microtubules; 3) The posterior kinetosome of the dorsal dikinetids bears the same fibrillar associates as the dorsal monokinetid, but it lacks the second transverse ribbon. The anterior kinetosome of each pair is associated with a single postciliary’ microtubule. The kinetid organization of Homalozoon is compared to that of other members of the Haptorida. Their phylogeny is discussed. A monophyleiic taxon within the litostomate ciliates is characterized by data on the somatic kinetids, and the new subclass Ditransversalia n. subcl. is constituted. The new subclass comprises the genera Balantidium, Bryophyllum, Enchelydium, Homalozoon, Isotricha, Lacrymaria, Lepidolrachelophyllum, Spathidium and Vestibulongum.
Identification of a cDNA Coding for the SerH3 Surface Protein of Tetrahymena thermophila
Authors: DOERDER F. PALL , HALLBERG RICHARD L.
Published: May 2007

We have identified a Tetrahymena thermophila cDNA‐containing plasmid (pC6) which hybridizes to a 1.47‐kB RNA whose changes in cellular concentration parallel the changes in synthetic rate of a major cell surface protein. From a molecular and genetic analysis of strains expressing the gene (SerH3) encoding this protein, and of strains expressing immunologically distinct alleles of this gene, we conclude that pC6 encodes a portion of the SerH3 allele.
The Somatic Function of the Germ Nucleus in Pseudourostyla cris tat a: Asexual Reproduction and Stomatogenesis
Authors: JIN LI‐PEI , NG STEPHEN F.
Published: May 2007

The micronuclei of the ciliated protozoan Pseudourostyla cristata were eliminated by amputation shortly before binary fusion. The amicronucleate cell lines derived from regenerants were maintained for more than a year. They exhibited a lower viability and reduced vigor in asexual propagation. There was some improvement in the growth of the cell lines 1 mo after operation, but the growth rate remained subnormal even up to 1 yr of culture. The exact cause of the poor growth and survival in the first 3 wk after operation, whether the loss of the micronucleus or operational damage, remains to be determined. It is nevertheless clear that the micronucleus is important for subsequent asexual propagation. The amicronucleate cell lines were permanently crippled in morphogenesis, unlike the situation in Paramecium amicronucleates in which stomatogenesis returned to near‐normal during asexual propagation. They always included some cells with a characteristically defective adoral zone of membranelles, reduced number of frontal‐ventral‐transverse cirri, and reduced body length. They were also reluctant to encyst. It is evident that the micronucleus is important for maintaining normality of the oral apparatus. It is postulated that the permanent stomatogenic crippling of amicronucleates might be related to genomic reduction in the developing macronucleus in sexual reproduction, as exhibited by other hypotrichs. The morphological defects associated with the adoral zone of membranelles may be rationalized as arising from the spreading of a zone of degeneration in the cortex affecting the left edge of the membranelles.
Eimeria tenella: Local Antibodies and Interactions with the Sporozoite Surface
Authors: TREES A. J. , KARIM M. J. , McKELLAR S. B. , CARTER S. D.
Published: May 2007

.Using fixed sporozoites in a 3‐layer immunofluorescence assay (TLIFA), class‐specific, parasite‐specific antibody responses in chicks to single‐pulse infection with Eimeria tenella have been studied in gut contents and bile as well as plasma and feces. After infection with 103 oocysts, IgA antibody was first detected in the duodenal lumen, then in bile, plasma, cecum, and the distal small intestine. The kinetics of the bile IgA response correlated with that in plasma and peaked 9 days post‐infection (d.p.i.); IgM was detected in gut contents and bile as well as plasma, and IgG was occasionally detected in gut contents, especially in the duodenum. In some experiments, IgA was detected in gut contents and bile to at least 21 d.p.i. Infection with 103 oocysts resulted in an earlier and increased response and relatively high IgG titers in cecal contents. Coproantibody was detected inconsistently and at low titer. When sporozoites that excysted in vitro were incubated in specific, antibody‐positive (9 d.p.i.) cecal contents, some complement‐mediated IgG‐associated anti‐sporozoite effects were observed; however, the major effect of cecal contents and the only effect of bile was a non‐lethal agglutination of living sporozoites. By fractionation of cecal contents and imtnunoblotting this was confirmed to be IgA mediated; IgA antibodies in cecal contents and bile after infection were shown to bind to sporozoite membrane antigens by surface fluorescence as well as agglutination. Agglutination detected anti‐sporozoite antibody in gut contents and bile up to 21 d.p.i., peaking between 7 and 13 d.p.i., corresponding with TLIFA results. The immunofluorescence studies reveal the extremely labile nature of the sporozoite surface antigens and support the hypothesis that naturally elaborated IgA antibodies are involved in the modulation of complexed sporozoite surface antigens.
Purification and Characterization of Clathrin‐Coated Vesicles from Chlamydomonas
Authors: DENNING GERENE M. , FULTON ALICE B.
Published: May 2007

Clathrin‐coated vesicles, identified by negative staining with uranyl acetate, were purified from Chlamydomonas rein‐hardtii. Isolated coated vesicles had diameters ranging from 70 to 140 nm (mean diameter±SD of 95±17 nm, n=300). These vesicles were markedly heterogeneous in both density and surface charge, as indicated by equilibrium density sedimentation and elution from anion‐exchange columns. Highly‐purified coated‐vesicle fractions contained 2 major polypeptides, identified as the clathrin heavy chain (185 kDa) and the clathrin light chain (40 kDa). Chlamydomonas clathrin heavy chain cross‐reacts weakly with an antibody against bovine brain clathrin heavy chain. Coat stability in several buffers was compared to that of bovine brain coated vesicles. Stability was similar, except for a greater stability of Chlamydomonas coated vesicles in 0.5 M Tris at pH 7.0.
Morphology and Construction of the Shell Wall in an Agglutinate Soil Testate Amoeba Phryganella acropodia (Rhizopoda)
Authors: OGDEN COLIN G. , PITTA PARASKEVI
Published: May 2007

ABSTRACT. When grown in culture, the soil testate amoeba Phryganella acropodia constructs a shell with or without mineral grains, but of identical morphology. The availability of organic shells, from these cultures, allows for detailed examination of the formation of organic building units in the cytoplasm and their subsequent use as a network in the shell matrix. Organic building units are initially formed as spherical membrane bound vesicles at the margins of dictyosomes, but mature in the cytoplasm by incorporating additional material, some have an electron dense core. These units remain pliable until they are moulded into the shell matrix. Another series of vesicles indistinguishable during initial formation from the organic building units, when mature contain a mass of small elements. This material is discharged at the same time as the building units and is thought to be the binding cement. Inorganic chemical elements appear to be incorporated within the inner lining of the matrix and the alveoli of the organic building units; manganese being preferentially absorbed under culture conditions.
A Method for Isolation of RNA from Pneumocystis carinii
Authors: CUSHION MELANIE T. , BLASE MARIA AIRO , WALZER PETER D.
Published: May 2007

ABSTRACT. Total RNA from Pneumocystis carinii obtained directly from the rat lung and from short term culture on A549 cells was evaluated for size and purity. An isolation procedure using guanidine isothiocyanate and lithium chloride was preferable to a hot phenol method. Host cells were eliminated by hypotonic lysis and a series of microfiltrations. Pneumocystis carinii were pretreated with Zymolyase for increased susceptibility to chaotropic agents. The major ribosomal species of P. carinii RNA migrated similarly to Saccharomyces cerevisiae rRNA. The 28s‐like species migrated well ahead of rat and A549 cell rRNA and well behind the prokaryotic large rRNA species.
Adherence of Pneumocystis carinii in Lung Cells during in Vitro Cultivation
Authors: BURNSTEIN THEODORE , RHODES JAN , TUREK JOHN
Published: May 2007

ABSTRACT
This study describes an approach to cultivation of Pneumocystis carinii (Pc) on 2 cell lines derived from lung (A549, human and L2, rat) with emphasis on the organisms which adhered to the cells. Immunofluorescent staining was used for growth assays
Morphology and Development of Mirror‐Image Doublets of Stylonychia mytilus
Authors: SHI XINBAI , FRANKEL JOSEPH
Published: May 2007

This paper describes the cortical anatomy and development of mirror‐image doublets of Stylonychia mytilus, analyzed using the protargol technique. The reversed, or “left‐handed” (LH) component of these doublets is a mirror image of the normal or “right handed” (RH) component with regard to the arrangement of cortical structures. The mirror‐image patterning is imperfect, however, as the individual ciliary structures of the LH component all are of normal internal asymmetry, and the orientation of membranelles is inverted. Certain structures that would be expected to form near the line of symmetry are absent. During cell division and cortical reorganization, ciliary primordia arise and become arranged in a mirror‐image pattern that is more perfect than that exhibited by the mature structures. Deviations from a mirror‐image pattern appear at late stages when organelle sets differentiate within ciliary primordia: for example, the membranelle set differentiates within the oral primordium of the LH component in a sequence that is an inversion rather than a mirror image of the corresponding sequence of the RH component. This mixed control of oral development by different cortical “informational systems” accounts for some of the characteristic abnormalities of the mature oral structures of the LH component.
Morphology and Development of Left‐Handed Singlets Derived from Mirror‐Image Doublets of Stylonychia mytilus
Authors: SHI XINBAI , QIU ZIJIAN , LU LI , FRANKEL JOSEPH
Published: May 2007

Mirror‐image doublets of Stylonychia mytilus include 2 sets of cortical structures, one with the normal “right‐handed” (RH) arrangement, the other with a reversed “left‐handed” (LH) arrangement. These sets, however, are incomplete, with certain structures, most notably cirri of the right marginal type, missing near the line of symmetry. When a mirror‐image doublet is bisected longitudinally to separate the RH and LH components physically, each fragment undergoes a regeneration process that restores a complete set of cortical structures, including the previously missing cirri of the right marginal type. In the resulting LH cell, all ciliary structures are present in an arrangement that is globally reversed in relation to that found in RH cells; in particular, marginal cirri of the left‐marginal type are formed at the cell's right margin, and marginal cirri of the right‐marginal type are produced at the cell's left margin. Whereas the regenerated RH fragment always divides and initiates a clone of normal singlets, the LH fragment, though structurally nearly complete, in all cases eventually dies without dividing. The cause of death is starvation due to the formation of an abnormal oral apparatus. In the Discussion, we consider the nature and consequences of a reversal of global positional information.
Gametogenesis in the Monothalamous Agglutinated Foraminifer Cribrothalammina alba
Authors: GOLDSTEIN SUSAN T. , BARKER WILLIAM W.
Published: May 2007

Gametogenesis in the foraminifer Cribrothalammina alba involves changes in both the gamontic test and cytoplasm. As gametes begin to differentiate and gametic flagella emerge, pores form in a regular array over the gamontic test, constituting the only avenue for gamete release. The spherical, biflagellated gametes average 1.5μ in diameter and are released in rapidly moving swarms along with flagellated “spherical masses” that probably result from incomplete gametic differentiation. Gametogenesis occurs entirely within the test and utilizes the entire cytoplast. After gamete release is complete, the agglutinated test collapses and disaggregates within a fairly short time. Similar modifications of the gamontic test occur during gametogenesis in Ovammina opaca Dahlgren, but are otherwise unknown among monothalamous agglutinated foraminifera at present.
Continuous Growth and Differentiation of Trypanosoma (Megatrypanum) freitasi Rego, Magalhaes & Siqueira, 1957, In Vitro
Authors: THOMAZ NEIDE , DEANE MARIA P.
Published: May 2007

Trypanosoma (Megatrypanum) freitasi, a parasite of didelphid opossum, was known to be very difficult to cultivate in conventional media. Co‐cultivation with L929 cell line in Baltz's medium at 27.5° C resulted in luxuriant growth of the trypanosome with the production of epimastigote colonies that adhered to the surface of culture flasks or tubes, and transformation into metacylics. Further transformation was stimulated by raising the incubation temperature. At 37° C the population was of the bloodstream type and resistant to lysis by complement.
Plasmodium falciparum: Increased and Multiple Invasion During Short Periods of Time
Authors: PAUL VERNOT JEAN , WASSERMAN MOISES
Published: May 2007

We describe how to obtain an increased merozoite invasion of Plasmodium falciparum into human erythrocytes during short periods of time. Using this procedure, infected erythrocytes show multiple invasions (2–4 merozoites per erythrocyte), amplifying, several times, the effects of parasite entry into host cells. The procedure yields synchronous cultures (2‐h age range) with parasitemia as high as 15%. It is possible to reach parasitemia of 50% or higher allowing for a 6‐h invasion period.
Influence of Pregnancy on the Course of Malaria in Mice Infected with Plasmodium berghei
Authors: HIOKI ATSUSHI , HIOKI YUKARI , OHTOMO HIROSHI
Published: May 2007

The course of malarial infection was compared in pregnant mice inoculated with Plasmodium berghei at different stages of gestation. When 12–14 wk old, pregnant BALB/c mice were inoculated with 1 × 106 of P. berghei NK65‐infected red cells at gestation day 0, 2, 4, 6, 8, 10, 12, 14 or 16, the mice inoculated on gestation days 6–12 expired 6.5 days after inoculation compared to 9.5 days in non‐pregnant mice. Parasitemia in these pregnant mice increased rapidly on day 4 after inoculation and anemia also developed earlier on day 5. However, the degree of parasitemia and anemia in the terminal stage of infection in these pregnant mice was milder than that of non‐pregnant controls. Blood urea nitrogen increased at the terminal stage although the degree of increase in mice inoculated on gestation days 6–10 was comparatively small. Pregnant malarial mice died earlier with less physiological changes than non‐pregnant controls. It was concluded that pregnancy makes the host susceptible to physiological changes caused by malaria.
Epizootiology of Amblyospora connecticus (Microsporida) in Field Populations of the Saltmarsh Mosquito, Aedes cantator, and the Cyclopoid Copepod, Acanthocyclops vernalis
Authors: ANDREADIS THEODORE G.
Published: May 2007

The natural ecology of a heterosporous microsporidium, Amblyospora connecticus was investigated at three different salt marsh habitats during 1986–1989. The parasite has a well‐defined seasonal transmission cycle that occurs regularly each year and intimately involves the primary mosquito host, Aedes cantator, and the intermediate copepod host, Acanthocyclops vernalis. In the spring, the microsporidium is horizontally transmitted from the copepod, where it appears to overwinter, to the mosquito via the ingestion of haploid spores produced in the copepod. Mosquitoes develop a benign infection, and females transmit the microsporidium transovarially to their progeny via infected eggs. Oviposition occurs during the summer and infected eggs hatch synchronously in the fall causing widespread epizootics. Infected larvae die, and the cycle is completed when meiospores are released into the pool and subsequently are eaten by A. vernalis, which reappears in the fall and early winter. Amblyospora connecticus thereby persists by surviving in one of two living hosts throughout most of its life cycle rather than in the extra‐corporeal environment. This represents an important survival strategy for A. connecticus as results show the salt marsh habitat to be a relatively unstable environment that is subject to periodic flooding and drying. The adaptive significance of utilizing an intermediate host in the life cycle is discussed as it directly facilitates transmission and enhances survival of the microsporidium.