bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunologic‐mediated Protection of Trypanosoma congolense‐Infected Mice by Polyribonucleotides
Authors: HERMAN ROBERT , BARON SAMUEL
Published: May 2007

SYNOPSIS. When the synthetic polyribonucleotides polyinosinic acid‐polycytidylic acid (poly I poly C) and polyadenylic acid‐polyuridylic acid (poly A poly U) were tested against mice infected with varying numbers of Trypanosoma congolense the results varied with the method of passage of trypanosomes in mice. Thus, when 100 flagellates were passaged every 7th day and experiments were initiated with these trypanosomes from mice on the 7th day of their infection, the protective effects of poly I poly C and poly A poly U apparently varied independently of each other as assayed by the mean parasitemias and cumulative mortalities of infected mice.

Poly I poly C‐resistant and poly I poly C‐susceptible variants (“R” and “S”, respectively) were isolated and maintained in mice by passage of 106 trypanosomes every 4th day. Mice infected with these variants responded consistently to poly I poly C and poly A poly U injections in that mice infected with the “R” variant showed no response to either polyribonucleotide but those infected with the “S” variant consistently had a decrease in mean parasitemias and cumulative mortality when treated with poly I poly C, but not with poly A poly U.

Using mice infected with the “S” variant, the protective effect of poly I poly C was dose‐dependent and best protection was afforded when 1st injections of poly I poly C were given around the time of infection of the mice.

The protective effects of the synthetic polyribonucleotides used in these experiments are probably due to their immunologic enhancing capacities and not to interferon. To support this, injections of Newcastle disease virus, a strong inducer of interferon in mice, did not protect against T. congolense in mice. It was not possible to determine whether serum from poly I poly C‐treated mice had a greater neutralizing effect upon trypanosomes in vitro than serum from saline‐treated mice since any effect of antibody was masked by a naturally occurring inhibitor in normal mouse serum which was reduced during infection. The protective effects of poly I poly C in T. congolense‐infected mice were reversed by treatment with cyclophosphamide. This strong immunosuppressant, however, could not reverse the protective effects of poly I poly C against mice infected with Semliki Forest virus, strongly suggesting that the protective mechanisms stimulated by poly I poly C in these 2 infections were different.

The response of mice infected with the “R” and “S” variants of T. congolense to synthetic polyribonucleotides is discussed in relation to antigenic variation of trypanosomes.
Sexual Stages in the Life History of the Hemogregarine Hepatozoon rarefaciens (Sambon and Seligmann, 1907)*
Authors: BALL GORDON H. , ODA SAM N.
Published: May 2007

SYNOPSIS. Sexual stages of a reptilian hemogregarine Hepatozoon rarefaciens are described from the hemocoele of a mosquito vector Culex tarsalis. The gametocytes associate within 0.5 hr after biting. Most of the gametocytes then pair off and begin to differentiate. After about 26 hr at 22–23 C, the macrogametocyte usually becomes crescent‐shaped with the microgametocyte lying in the concavity. The nucleus of the macrogametocyte enlarges considerably, while the microgametocyte divides into 2 and eventually into 4 spindle‐shaped microgametes which are biflagellated. The macrogametocyte increases in size and rounds up to form a macrogamete. Gamete formation is usually completed by 60 hr and fertilization begins soon thereafter. The zygotes develop into the uninucleate oocysts described previously. In some other species of Hepatozoon, gametogenesis has been described as taking place in the stomach of the arthropod vector, with the microgametocytes transforming without cytoplasmic division into non‐flagellated microgametes. The occurrence of 2 distinct types of gametogenesis may possibly be a basis for separating Hepatozoon into 2 genera.
Arginine Transport in the Culture Form of Trypanosoma cruzi
Authors: HAMPTON JAMES R.
Published: May 2007

SYNOPSIS. Arginine in Trypanosoma cruzi is taken up by a mediated transport system; a large non‐saturable component is also involved. Arginine transport specificity in T. cruzi is unusual since lysine and histidine do not inhibit its uptake. Glycine and valine are partially competitive inhibitors and homoarginine, alanine and methionine are completely competitive. At least one arginine transport site is so specific that homoarginine will not react with it. Apparently the diamino acid transport systems of T. cruzi have undergone major evolutionary modifications.
Taxonomy of the Archigregarinorida and Selenidiidae (Protozoa, Apicomplexa)*
Authors: LEVINE NORMAN D.
Published: May 2007

SYNOPSIS. The gregarine order Archigregarinorida is redefined. The new family Selenidioididae is established in it, containing the genera Selenidioides n. g. with 11 species, Meroselenidium with 1 and Merogregarina with 1. The new family Exoschizonidae is also established in it, with 1 genus, Exoschizon, containing 1 species. The family Selenidiidae is transferred to the order Eugregarinorida in a new superfamily, Lecudinicae, and redefined to exclude the presence of merogony. As redefined, the family Selenidiidae contains the genera Selenidium with 33 species, Selenocystis with 1 and Ditrypanocystis with 2. The following new species are named: Selenidioides fanthami, S. hawesi, Selenidium mackinnonae, S. martinensis, S. rayi, Ditrypanocystis coxi. The following new combinations are introduced: Selenidioides axiferens, S. caulleryi, S. giganteum, S. hollandei, S. intraepitheliale, S. mesnili, S. metchnikovi, S. potamillae, S. sipunculi, Selenidium synaptae. In addition, the septate form from Cirratulus cirratus that was named Polyrhabdina cirratulus by Bogolepova (2) is renamed P. bogolepovae n. sp.
A New Aspect of Trypanosoma cruzi Life‐Cycle in the Invertebrate Host
Authors: BRENER Z.
Published: May 2007

SYNOPSIS. Trypanosoma cruzi blood trypomastigotes transform, in the stomach of the invertebrate host, into round or pear‐shaped forms. A certain number form attached pairs or large masses of aggregated amastigotes. Cytoplasmic bridges and membrane leaks may be observed between apposed parasites. There are fusion of the organisms, an apparent disorganization of the DNA‐containing organelles and thickening of the borders of the parasite aggregates. From those borders single or small clumps of flagellates begin to detach and liberate. The meaning of this heretofore overlooked sequence of events as well as the possibility of genetic exchange among the parasites in the early stages of development are discussed.
Proline Metabolism in Tetrahymena1
Authors: DEWEY VIRGINIA C. , KIDDER G. W.
Published: May 2007

SYNOPSIS. By the use of 14C‐labeled substrates it has been shown in Tetrahymena that proline is rapidly and completely oxidized to carbon dioxide and glutamate (65–70%), plus small amounts of aspartate and alanine (20%), the remainder being incorporated into macromolecular cell components. In comparison, acetate, glucose and glutamate are oxidized to a lesser extent (55%, 37% and 16%, respectively). Glucose and acetate are extensively incorporated into cell components (53% and 36%, respectively), while glutamate remains in the medium (76%). Thus proline is a source of readily available energy.
Ultrastructural Study of Gametocytes and Gametogenesis of Haemoproteus metchnikovi
Authors: STERLING CHARLES R.
Published: May 2007

SYNOPSIS. The ultrastructure of gametocytes and microgametogenesis of Haemoproteus metchnikovi, an intracellular malaria parasite of chelonians, was compared with other malarial parasites. Gametocytes resemble those described for other avian, reptilian and mammalian malarial parasites. The process of microgametogenesis is similar in many respects to that reported for Leucocytozoon simondi (Aikawa et al., 1970) and Haemoproteus columbae (Bradbury and Trager, 1968). Atypical centrioles are described from both microgametocytes and macrogametocytes. Axoneme development begins before the microgametocyte leaves the host red blood cell. Fully developed microgametes which bud off from the parent gametocyte contain a single axoneme with the typical 9 + 2 pattern of microtubules.
Serologic Changes Associated with the Encystment of Axenically Grown Hartmannella culbertsoni*
Authors: RAIZADA M. K. , SAXENA K. C. , MURTI C. R. KRISHNA
Published: May 2007

SYNOPSIS. Serologic reactions elicited by sonically ruptured trophic and cystic forms of Hartmannella culbertsoni were studied. The antigens of trophic amoebae reacted with their homologous rabbit antiserum showing multiple precipitin lines which could not be seen when the reacting antigens were treated with trypsin prior to application on the Ouchterlony plates. Antigens of trophic amoeba did not react with antiserum against cysts. Cyst antigens reacted with their homologous antiserum only after trypsin treatment. Antigens prepared from trophozoites excysting from cysts reacted positively with the antiserum against antigens of trophic amoebae.

Antigens of trophic as well as cystic forms fixed guinea pig complement in presence of their homologous antisera. With the trophic form, this property was abolished after trypsin treatment. Non‐specific complement fixation mediated by cyst antigens was abolished by treatment with cellulase. Antiserum against trophic amoebae immobilized trophozoites and, in the presence of guinea pig complement, led to their lysis.
Axenic Mass Cultivation of Entamoeba invadens and Cell Membrane Isolation
Authors: SPIES F. , ELBERS P. F.
Published: May 2007

SYNOPSIS. A method for axenic mass cultivation of Entamoeba invadens is described. A known monophasic culture medium for E. histolytica was modified by mixing it with a medium for Acanthamoeba castellanii and adding ferric chloride to provide more particulate material. This results in a high number of cells per ml after a relatively short culture period.

A cell membrane fraction of such a mass culture of E. invadens can be prepared by simple disruption of the cells and by low speed centrifugation. Owing to the lack of membrane‐bounded organellae in the amebic cytoplasm there are only 2 kinds of membranes to be separated: the plasmalemma and the vacuole membranes.
Fine Structure of the Surface and Infraciliature of Gastrostyla steinii
Authors: GRIM J. NORMAN
Published: May 2007

SYNOPSIS. In many hypotrich ciliate protozoa there are at least 6 possible categories of ciliary structures: right marginal cirri, left marginal cirri, fronto‐ventral‐transverse cirri, membranelles, and 2 oral membranes. This report describes the kinetosomes, fibrils and microtubules which make up the cytoplasmic portion of these structures in Gastrostyla steinii.

Altho light microscope studies have revealed significantly different infraciliature for the 3 classes of cirri, the fine structure of these locomotor organelles indicates that they have a remarkable number of homologous structures. There is also a number of apparent homologies between the cirri of this organism and ciliary structures of both more primitive and more highly evolved ciliates. The oral ciliature of G. steinii is analyzed and compared to that of other spirotrichs for clues to the phylogeny of the hypotrichs. Function of the infraciliature is considered briefly.
A New Species of Henneguya (Myxosporidea: Myxobolidae) from the Black Drum Pogonias cromis in Clear Lake, Texas
Authors: JOY JAMES E.
Published: May 2007

SYNOPSIS. Henneguya texana n. sp. (Myxosporidea: Myxobolidae) is described from the gill filaments of 2 out of 47 specimens of marine sciaenid fish Pogonias cromis collected from Clear Lake, Texas. The spore body is 7–9 by 6–7 μ (mean 8.1 by 6.7 μ) with a thickness of 4–5 μ (mean 4.7 μ). The 2 fused, tapering caudal processes are 36–59 μ (mean 48.65 μ) long. The parasitized fish were collected in December 1970 and January 1971 were 168 and 482 mm in total length, respectively.
Rapid Scanning Microspectrophotometry of Colorless Euglena gracilis and Astasia longa. A Basis for Differentiation
Authors: ROGERS TOM D. , KIMZEY STEPHEN L.
Published: May 2007

SYNOPSIS. Automated cell identification by computer‐assisted analyses of data obtained by ultraviolet microspectrophotometry has been applied as a means of distinguishing between 2 structurally similar euglenoids, colorless Euglena gracilis and Astasia longa. Quantitative differences of nuclear extinction values of individual cells provided a basis for species separation. Since the highly plastic nature of the organisms resulted in variable structure of the air‐dried cells, the size and shape of the organisms were disregarded as descriptors. Spherical cells were identified as readily as cells with the typical elongate structure. Misclassfication of cells was attributed to the stage of the cell in the cell cycle and the quantitative differences of nucleoprotein as determined by ultraviolet cytophotometric data.
The Ultrastructure of Trophozoites of Entamoeba histolytica with Particular Reference to Spherical Arrangements of Osmiophilic Cylindrical Bodies
Authors: FERIA‐VELASCO ALFREDO , TREVINO NORBERTO
Published: May 2007

SYNOPSIS. Trophozoites of Entamoeba histolytica were cultured under xenic, monoxenic and axenic conditions. Some of the monoxenically cultured trophozoites were grown in the presence of Bacteroides symbiosus and others in the presence of Trypanosoma cruzi (Mexican strain). Other trophozoites were obtained from experimentally produced amebic liver abscesses in hamsters. The trophozoites were centrifuged and prepared for study by electron microscopy. Acid phosphatase activity in the parasites was determined by cytochemical reactions.

The various elements of the trophozoites were described and special attention was given to the spherical arrangements of electrons‐dense cylindrical units surrounding finely granular material. Their presence was independent of the strain studied and of the nutrient elements in the culture medium. The cylindrical units probably arise from endoplasmic reticulum elements and their possible function in the digestive processes and aggression mechanisms of the trophozoites is discussed.

Acid phosphatase activity was found in round non‐branching intranuclear bodies in trophozoites cultured in various media. Whether these bodies represent part of the lysosomal system of the parasite is unknown.

In preliminary work on the action of some amebicidal drugs, a special arrangement of cytomembranes morphologically similar to a Golgi complex was frequently seen in trophozoites of E. histolytica.
The Structure of the Oocyst and the Excystation Process of Isospora marquardti sp. n. from the Colorado pika, Ochotona princeps
Authors: DUSZYNSKI DONALD W. , BRUNSON JOHN T.
Published: May 2007

SYNOPSIS. Oocysts of Isospora marquardti sp. n. from the Colorado pika, Ochotona princeps, have spheroid oocysts, 30.5 (23–36) μm in diameter, and ovoid sporocysts, measuring 19.3 × 12.0 (17–22 × 10–14) μm. A polar body, 2 × 4 μm, a spheroid sporocyst residuum (8.3 μm in diameter), a Stieda body, and a distinct substiedal body (3 × 3 μm) are present. A micropyle and an oocyst residuum are absent. Excysted sporozoites, averaging 3.0 × 18.5 (2–4 × 15–20) μm, contain 2 refractile globules, 1 on each side of the nucleus with a prominent nucleolus.

The sporozoite excystation process using a trypsin‐sodium taurocholate fluid is described.
Gametocyte Maturation, Exflagellation and Fertilization in Parahaemoproteus (=Haemoproteus) velans (Coatney & Roudabush) (Haemosporidia: Haemoproteidae): an Ultrastructural Study*
Authors: DESSER SHERWIN S.
Published: May 2007

SYNOPSIS. The structural changes in macro and microgametocytes of Parahaemoproteus velans following removal of infected blood from the avian host were studied in the light and electron microscope. Gametocytes of both sexes round up and soon escape from their host cells. Shortly thereafter they assume a dumbbell shape. The microgametocyte undergoes exflagellation forming 8 slender microgametes. During fertilization the entire microgamete appears to enter the female. The most striking ultrastructural change in the formation of the macrogamete is the condensation and enclosure by a membrane of abundant amophorus dense material seen in the cytoplasm of the immature gametocyte. Maturation of the microgametocyte begins prior to its escape from the host cell. Axonemes are present in the cytoplasm and nuclear reorganization occurs while the parasite is intracellular. Bundles of microtubules associated with condensed chromatin are found in the peripheral cytoplasm of maturing forms and apparently participate in the formation of small compact microgamete nuclei. Each of these filiform structures consists of a dense, centrally located nucleus and a single axoneme lying in flocculent cytoplasm. The nucleus and axoneme of the microgamete are seen free in the cytoplasm of a fertilized macrogamete.
Analysis of the Antigenic Relationships Among Trichomonas, Histomonas, Dientamoeba, and Entamoeba.* II. Gel Diffusion Methods
Authors: DWYER DENNIS M.
Published: May 2007

SYNOPSIS. Antisera were developed in rabbits against Trichomonas gallinae, Histomonas meleagridis, Dientamoeba fragilis, Entamoeba invadens, and Entamoeba histolytica. In reactions between these antisera and antigens prepared from each of the 5 species the most numerous and strongest precipitin lines appeared on gel diffusion agarose plates between the homologous antigens and antisera. Anti‐Trichomonas serum cross‐reacted most strongly with Histomonas, somewhat less with Dientamoeba, but gave no lines with the 2 species of Entamoeba. Anti‐Histomonas serum cross‐reacted strongly with both Trichomonas and Dientamoeba, and weakly with E. invadens and E. histolytica. Dientamoeba antiserum gave many precipitin lines with Histomonas, fewer with Trichomonas, and fewest with the 2 species of Entamoeba. Stronger reactions were noted between anti‐Dientamoeba serum and E. invadens than between this serum and E. histolytica. Immune sera prepared against the 2 species of Entamoeba gave the most numerous precipitin lines in intrageneric cross‐reactions, but the reaction between either of these antisera and Histomonas was weak. Somewhat stronger reactions were observed between the 2 anti‐Entamoeba sera and Dientamoeba. Trichomonas failed to react with either of the anti‐Entamoeba sera.
Periodicity of Nuclear DNA Synthesis in the Intraerythrocytic Cycle of Plasmodium knowlesi
Authors: GUTTERIDGE W. E. , TRIGG P. I.
Published: May 2007

SYNOPSIS. Preparations of the various intraerythrocytic stages of Plasmodium knowlesi nearly free of host‐cell material were made from infected rhesus monkey blood. Analyses of these revealed that late trophozoite and schizont stages contain similar amounts of DNA and that ring stages contain much less DNA. This indicates that DNA synthesis occurs mainly during the ring and trophozoite stages of the cycle. Attempts to confirm these results using a quantitative Feulgen staining technique yielded anomalous results.

The analytical data indicated that incorporation of 3H‐adenosine rather than of 3H‐orotic acid, was the better indicator of DNA synthesis in P. knowlesi in culture. A detailed study with time course and pulse‐labelling experiments showed that incorporation of 3H‐adenosine occurred at a similar rate throughout the intraerythrocytic cycle until schizogony began, that it ceased during this period, and began again as soon as the parasites had invaded new cells.

It is concluded that the S‐phase of the cell cycle occupies most of the ring and trophozoite stages and that the G1 and G2 phases, if they occur, are of short duration. The amount of DNA in the nucleus is increased 10–20 fold during the S phase. At schizogony, the nucleus divides without further DNA synthesis to yield a 16‐nuclear schizont.
A Man to Remember, E. Fauré‐Fremiet (1883–1971): Three‐Quarters of a Century of Progress in Protozoology*
Authors: CORLISS JOHN O.
Published: May 2007

SYNOPSIS. The late Professor Emmanuel Fauré‐Fremiet, nearly 88 years old at the time of his passing in November 1971, was not only an outstanding leader in ciliate protozoology but also a general cytologist, experimental embryologist, and electron microscopist of note, and, in earlier years, a sculptor and painter of merit. Both born and marrying into celebrated families, “Monsieur Fauré” led a career of his own filled with honors and distinction, but he remained a sensitive, modest man, remembered, too, for his ever‐present sense of humor. Author of nearly 500 books and papers in diverse fields of biology, Fauré‐Fremiet made his most lasting contributions in the realms of synthesis, innovative hypotheses, and heuristic ideas.
Eimeria and Klossia spp. (Protozoa: Sporozoa) from Wild Mammals in Borneo*
Authors: MULLIN STEVEN W. , COLLEY FREDRICK C.
Published: May 2007

SYNOPSIS. During a survey of parasites of Sabah mammals, coccidia oocysts were found in 9 of 22 host species examined. Sporulated oocysts of Klossia sp. from Rattus whiteheadi are described. New geographic records are reported for Eimeria callosciuri, Eimeria sabani, and Eimeria tupaiae. New host and geographic records are reported for Eimeria separata from Rattus cremoriventer, for E. tupaiae and Eimeria ferruginea from Tupaia tana, for Eimeria nieschulzi from Rattus muelleri, and for E. sabani and Klossia sp. from R. whiteheadi.
Cortical Structure in Nondividing and Cortical Morphogenesis in Dividing Oxytricha fallax*†
Authors: GRIMES GARY W.
Published: May 2007

SYNOPSIS. Light‐ and electronmicroscopic observations of nondividing Oxytricha fallax revealed a high degree of cortical complexity in this species and provided much additional detail to previous descriptions of hypotrich ciliates.

By the same microscopic methods, the morphogenetic pattern of O. fallax was found to be similar to that of other hypotrich genera with regard to the formation of oral primordium in association with cirri and to the incorporation of specific cirri into cirral primordia. There is no donation of any cirral part to the oral primordium, but cirri involved in cirral primordia formation appear to be donated fully to these primordia. Attainment of final form and size of the oral primordium and new cirri is a multistep process. Alignment of kinetosomes to form membranelles occurs first in pairs, the immature membranelles containing only 2 rows of kinetosomes. The 3rd and 4th rows are added by production of new kinetosomes from right to left on the anterior edge of each membranelle. Cirral development, likewise, is not completed until individual new cirri are distinguishable, new kinetosomes being added as the cirri move to their final locations on the organism's surface.

The cirral resorption process also is reported briefly. Means of experimental analysis of the possible role of individual cortical structures in morphogenesis is discussed.
An Electronmicroscopic Study of the Microgamete of Haemoproteus columbae Kruse*
Authors: AILOR BARBARA JECKEL
Published: May 2007

SYNOPSIS. Microgametes of Haemoproteus columbae were studied by light microscopy and electron microscopy, using the single‐stage replication technic. The filiform microgamete has a swelling or vesicle near the round end; the opposite end is asymmetrically tapered. The gamete is polarized, for it travels in sinuous movements with the round end (the putative anterior end) directed forward. There is no flagellum or undulating membrane and no mitochondrion. The vesicle may contain energy reserves for locomotion or lytic enzymes for penetration. Tubular material often is seen coming from the vesicle and anterior end and may be a kind of acrosomal filament.
Fine Structure of Developing Spores of Thelohania bracteata (Strickland, 1913) (Microsporida, Nosematidae) Emphasizing Polar‐Filament Formation*
Authors: LIU T. P. , DAVIES D. M.
Published: May 2007

SYNOPSIS. In the microsporidian, Thelohania bracteata, the polar filament, as it starts to develop in the sporoblast, apparently receives material synthesized by the granular endoplasmic reticulum and Golgi vesicles. In immature spores many dilated sacs are observed in areas where there is less endoplasmic reticulum. These sacs, that persist into the almost mature spore, are probably Golgi‐type vesicles and may be related to the formation of the spore coat. The polar filament of the mature spore possesses 8 coils and in cross section or cross‐fractured face the electron‐dense central portion of the polar filament contains a tubular structure, ringed by 12–14 cylindrical structures. In thin sections, an electron‐lucid zone is observed between the core and membrane of the polar filament. The polar filament runs through the highly laminated polaroplast which occupies the anterior portion of the spore. In cross‐fractured face the lamellae of the polaroplast are arranged like the petals of a flower. The basal portion of the polar filament is enlarged, appearing arrow‐shaped in thin sections and pear‐shaped in frozen‐etched preparations. Frozen‐etched membranes differ in the size and distribution of the surface particles.
Pellicle of Paramecium caudatum as Revealed by Freeze Etching
Authors: JANISCH ROMAN
Published: May 2007

SYNOPSIS. Freeze etching study of Paramecium caudatum surface reveals a regular pattern formed by depressions equipped with a single or paired cilia. This picture is consistent with the generally accepted concept of Paramecium cortex based on conventional methods of study. The surface of the ciliate is covered with small globular particles ∼14 nm in diameter, which have been found also on the plasma membrane of other cells. In the areas where the tips of trichocysts are attached to the pellicle, the globular particles are arranged into circles 0.4 μm in diameter. The whole surface of Paramecium is covered by a smooth thin layer which, always chipped off during fracturing, is detectable only after etching.
Results of Intracecal Inoculation of Germfree and Conventional Guinea Pigs and Germfree Rats with Axenically Cultivated Entamoeba histolytica
Authors: PHILLIPS BRUCE P. , DIAMOND LOUIS S. , BARTGIS IDA LOUISE , STUPPLER STEPHEN A.
Published: May 2007

SYNOPSIS. Germfree and conventional guinea pigs and germfree rats were inoculated with large numbers of axenically cultivated Entamoeba histolytica. Amebic lesions were not found in any of the animals, and there was no indication that the ameba had established lumen infections in any instance. The axenic amebae appeared to have lost their pathogenicity. This loss was believed to depend, in part at least, upon the fact that they did not encyst and thus did not complete their life cycle in axenic culture.
An Immobilization Antigen in Tetrahymena pyriformis Expressed Under Conditions of High Salt Stress*
Authors: GRASS FRANK S.
Published: May 2007

SYNOPSIS. Cells of Tetrahymena pyriformis syngen 1 exposed to 200 mM NaC1 without previous exposure to a saline medium die within minutes. Lines that have been adapted to higher salt concentrations by growing in axenic peptone medium with 100 mM NaC1 are able to grow in previously intolerable concentrations. Acclimation to higher salt concentrations is accompanied by a transformation from the H serotype, expressed at room temperature in the standard peptone medium, to a new serotype, St. Complete transformation occurs at concentrations approaching the LD50 for nonadapted cells, and the time required for the transformation is 3–4 days. The reverse transformation, St to H, involves a time interval during which the cells are refractory to both anti‐St and anti‐H. Among 12 of the 13 inbred families of T. pyriformis syngen 1, 2 different high salt serotypes are found. One of these, Sta, is found among families A, Al, A3, B, D, D1, E, and F. The other, Stc, occurs in families C, C1, C2, C3, and possibly B2.
Plasmodium berghei NK65 in the Inbred A/J Mouse: Age Immunity in the Female Retired Breeder A/J Mouse*
Authors: ALGER NELDA E. , BRANTON MARILYN , HARANT JOYCE , WILLIS LINDA , SILVERMAN PAUL H.
Published: May 2007

SYNOPSIS. Death rates of A/J and CF1 female mice 4 weeks and 6 months of age were compared after the mice were infected with Plasmodium berghei NK65C deme (population) and NK65RR deme. Death rates were compared also when female A/J retired breeder mice were infected with blood passages 18 and 40 of NK65C.

NK65C was found to be less virulent than NK65RR. The 40th blood passage of NK65C was more virulent than the 18th passage, but still not as virulent at the NK65RR deme. A/J retired breeders were clearly more resistant to infection than 4 week old A/J mice, while little difference was found in the different age groups of the CF1 mice.
Deoxyribonucleic Acid Base Composition of Some Cellular Slime Molds*
Authors: DUTTA S. K. , MANDEL M.
Published: May 2007

SYNOPSIS. Deoxyribonucleic acids (DNAs) isolated from 12 representatives of cellular slime molds grown in monoxenic cultures were analyzed by density gradient centrifugation in CsC1. The unique contribution of the DNA of each food organism was subtracted and the DNA base composition of each cellular slime mold determined. The guanine plus cytosine contents range 22–37 moles % within the representatives of the order. Minor bands (satellite bands) of DNA have been observed in preparations from Dictyostelium spp. and from Polysphondylium pallidum.
A New Saurian Malaria Parasite Plasmodium clelandi sp. n. from Ceylon*
Authors: MANAWADU BINGUMAL R.
Published: May 2007

SYNOPSIS

Plasmodium clelandi sp. n. is described from Varanus cepedianus of Mannar District, Ceylon. The earliest asexual stages were seen as a chromatin dot. Trophozoites have a vacuole with chromatin material spread around its periphery. The trophozoites divide and mature to form the schizont.

The maximum number of merozoites observed in a schizont was 8. Pigment was scanty and sometimes absent. The gametocytes had a characteristic elongate form and tend to encircle the host cell nucleus.
Cyclidium citrullus Cohn, a Ciliate from the Hot Springs of Tiberias (Israel)
Authors: KAHAN DAVID
Published: May 2007

SYNOPSIS

A thermophilic ciliate Cyclidium citrullus (Hymenostomatida) was collected from Tiberias hot springs at temperatures of 50–58 C. In the laboratory, the ciliates were grown in monoxenic cultures with Escherichia coli in a mineral medium of 3% (w/v) salts similar in composition to that of the hot springs. C. citrullus tolerates a wide range of temperatures, 18–47 C. The optimal temperature is ∼44 C. The ciliates could tolerate direct transfer to salt concentrations of 0.2–7.0% (hot springs composition). No cysts or other dormant forms have been observed. A description of the ciliate based on living and stained specimens is given. The taxonomy and ecology of Cyclidium from hot springs is discussed.
A Redescription of Rhyncheta cyclopum Zenker (Ciliatea, Suctorida)*
Authors: HITCHEN E. T. , BUTLER R. D.
Published: May 2007

SYNOPSIS

Rhyncheta cyclopum Zenker (Ciliatea, Suctorida) is described from Cyclops albidus and C. viridis occurring in small lakes in Cheshire. The adults have elongated or irregularly spherical bodies which are rounded apically and flattened basally. There is usually a single primary tentacle which is variable in position, length, and activity. Additional tentacles in various stages of growth and resorption may be present, and an account of these processes is given. The body is attached to the host by a short stalk. The barrel‐shaped embryos are produced by a rapid or multiple endogenous budding. The presence of the stalk and supernumerary tentacles are described for the first time, and it is considered that these, together with other features, warrant a redescription of this species. The taxonomic relationship of R. cyclopum to other species of Rhyncheta is considered and a probable connection of the tentacle form in this suctorian with its possible food source is discussed.
Kinetosome Production in Condylostoma Occurs During Cell Division*
Authors: DE TERRA NOEL
Published: May 2007

SYNOPSIS

Kinetosome counts in different stages of the cell cycle of Condylostoma indicate that somatic kinetosome production occurs during cell division. The kineties apparently increase in length during interphase by spacing‐out of preexisting kinetosomes. This spacing‐out may be passive and caused by expansion of the cortical membrane to which the kinetosomes are attached.
Euplotes raikovi Agamaliev, 1966 (Ciliophora, Hypotrichida) From New Hampshire: Description and Morphogenesis
Authors: WASHBURN EDWARD S. , BORROR ARTHUR C.
Published: May 2007

SYNOPSIS

Euplotes raikovi, an interstitial hypotrich ciliate described once from the Caspian Sea, was isolated from intertidal sand at Rye Harbor, New Hampshire. Specimens were observed in life, and also stained by Corliss’ modification of the Chatton‐Lwoff wet‐silver technic and by 2 nigrosin methods. Living individuals and those fixed with Parducz's fluid are 43 × 30 (37‐50 × 25–35) μm. The AZM has an average length of 27 μm and contains 24–32 membranelles. The anterior part of AZM lies on the ventral face of an apical channel, much as in E. bisulcatus. There are 7 fronto‐ventral, 4 transverse, 1 left marginal, and 2 right caudal cirri. An additional small, rounded argentophilic area resembling a cirrus base is evident in silver‐stained preparations, but it is barren in virtually 100% of the population. There are 7–8 (usually 7) dorsal ciliary rows with E. patella‐type argyrome. The modal number of cilia in rows I‐VII are 3‐7‐9‐9‐9‐10‐10. The unique fronto‐ventral cirrus pattern is stable and predictable at the time of streak phase. Morphogenetic development indicates that the barren cirrus base is 2/V (Wallengren system), and that it apparently buds from 1/V. The left marginal cirrus and right caudal cirri have different origins.
Effect of Viscosity on Formation and Sedimentation of Polytomella agilis Vertical Aggregates*
Authors: GITTLESON STEPHEN M. , ROGERS MICHAEL
Published: May 2007

SYNOPSIS

The response of vertical aggregates of Polytomella agilis to increased viscosity of the medium indicates that viscous resistance of the medium is a critical factor controlling the formation and sedimentation of protozoan aggregates. Aggregate formation time increased from 20 sec to 6.5 min as viscosity was increased 1.72 times. Sedimentation rate decreased about 140 μm/sec for each 10% increment in viscosity. Although there was a 60% decrease in speed of falling aggregates when relative viscosity was increased from 1.0 to 1.6, individually swimming P. agilis decreased less than 22% in speed even at a relative viscosity of 1.84 where aggregates did not form. Cells continued to accumulate near the surface by negative geotactic swimming after vertical aggregation ceased. Vertical aggregation is a cyclic process composed of 4 phases: a) accumulation‐aggregation; b) aggregate sedimentation; c) ablation and dispersal; and d) negative geotaxis. Phase d is unique to motile microorganisms and only in such populations is vertical aggregation continuously selfperpetuating. Phases a‐c occur with both motile and nonmotile bodies and are dependent upon viscous forces of the medium.
Division and Formation of the Macronuclei of Keronopsis rubra*
Authors: RUTHMANN AUGUST
Published: May 2007

SYNOPSIS

The hypotrichous ciliate Keronopsis rubra has ∼10 micronuclei and ∼100 small macronuclei. DNA synthesis proceeds synchronously in all macronuclei in the 2nd half of the cell cycle which takes about 24 hr at room temperature. A G2 phase is virtually absent, each nucleus dividing as soon as the replication band has passed over it. The micronuclear S phase falls within macronuclear G1 and is followed by immediate division. Comparative cytophotometric measurements of Feulgen‐stained preparations indicate that the DNA content of G1 macronuclei is scattered widely in a skewed normal distribution, with a peak corresponding to the DNA content of a G1 micronucleus. Measurements of dividing macronuclei indicate unequal distribution of DNA between daughter nuclei and lead to the conclusion that the units of assortment must be smaller than whole genomes unless the micronucleus is polyploid. After conjugation, a large macronuclear anlage with threads resembling split prophase chromosomes is formed. The threads condense and pass singly into the cytoplasm where they are thought to give rise to the numerous small macronuclei of the vegetative cells.
Hyalophysa Iwoffi sp.n. from the Fresh‐water Shrimp Palaemonetes paludosus and Revision of the Genus Hyalophysa
Authors: BRADBURY PHYLLIS CLARKE , CLAMP JOHN C.
Published: May 2007

SYNOPSIS. Hyalophysa Iwoffi sp. n. is described from the shrimp, Palaemonetes paludosus. Its life cycle is like that of other exuviotrophic apostomes. Hyalophysa Iwoffi differs from the type species, H. chattoni, in the details of its infraciliature and the shape of its macronucleus during the trophont stage. Emended diagnoses of the genus, Hyalophysa, and the species, H. chattoni, also are given.
Fine‐Structural Changes Associated with Pseudocyst Formation in Trichomitus batrachorum*
Authors: MATTERN CARL F. T. , HONIGBERG B. M. , DANIEL WENDELL A.
Published: May 2007

SYNOPSIS. Several fine‐structural changes were observed during formation of the so‐called pseudocysts of Trichomitus batrachorum grown in an agar‐free medium. Among these changes the most frequent were those of the undulating membrane complex. Internalization of the marginal lamella combined with disappearance of the fin‐like, membranous dorsal fold occurred with the highest frequency. In many organisms these alterations were accompanied by internalization of the recurrent flagellum, which, however, remained external in other, presumably earlier stages of pseudocyst formation. In some of the internalized and even still external recurrent flagella the microtubules were in various states of disassembly. The often distended flagellar membrane enclosed large accumulations of filaments 5 nm in diameter. Internalization of the anterior flagella also was noted. Changes similar to those characteristic of the recurrent flagella were not seen, however, among the microtubules of the anterior flagella or among those of the pelta or the axostyle.
Intranuclear Inclusions in the Ameboid Cells of Protostelium zonatum*
Authors: HUNG CHING‐YUAN , OLIVE LINDSAY S.
Published: May 2007

SYNOPSIS. Two morphologically distinct types of intranuclear inclusions are found in ameboid cells of the protostelid mycetozoan Protostelium zonatum. One type of inclusion is a coiled tubular structure which in cross section appears as cisternae and oval to elliptical vesicles 40–60 nm in diameter. These tubular and vesicular structures are formed by a unit membrane that is connected directly with the inner nuclear membrane. The other type of inclusion is a membrane‐bound structure that contains amorphous and/or fibrous material. These inclusions usually are present at several locations in a nucleus. No similar structures occur in the cytoplasm.
Conformational Changes in the Cortical Region during Peristaltic Movements of a Gregarine Trophozoite*
Authors: MACMILLAN W. G.
Published: May 2007

SYNOPSIS. Light‐ and electronmicroscopic studies of noncontracted and contracted regions of Nematocystis magna Schmidt (Gregarinida) trophozoites revealed that their peristalsis‐like movements are accompanied by conformational changes in the folded limiting membrane and underlying layer of transverse fibrils. Noncontracted and contracted regions of individual trophozoites had “folded'’and “superfolded'’configurations respectively. Measurements of periodicity and through‐focus studies, together with the sequential use of the same Araldite sections for light and electron microscopy, aided in identification of longitudinal fibrils of varying sizes (light microscopy) with specific conformations of the epicytary folds (electron microscopy) in contracted and noncontracted states.
Fine‐Structural Aspects of Macrogametogenesis in Eimeria magna*†
Authors: SPEER CLARENCE A. , HAMMOND DATUS M. , YOUSSEF NABIL N. , DANFORTH HARRY D.
Published: May 2007

SYNOPSIS. Macrogamonts in tissues from rabbits killed 5 1/2 days after inoculation with Eimeria magna oocysts were studied with the electron microscope. In young macrogamonts, parts of cytoplasm, sometimes including micronemes, were pinched off into the parasitophorous vacuole. In all stages of development, small segments of the inner membrane complex were present beneath the limiting membrane. Micropores also were seen in all stages, and some apparently functional ones were present in mature macrogametes. Wall‐forming bodies of Type I and Type II were observed in relatively early stages. The former were less numerous than the latter, which had a more compact appearance than in other species. Usually, several Golgi complexes were present and several Golgi adjuncts occurred in the vicinity of the nucleus in all stages of development. Microgametes were observed in the cytoplasm of host cells harboring immature macrogametes.
Foreign Organelle Retention by Ciliates
Authors: BLACKBOURN D. J. , TAYLOR F. J. R. , BLACKBOURN JANICE
Published: May 2007

SYNOPSIS. Intact algal chloroplasts were found by electron microscopy in the peripheral cytoplasm of 2 ecologically important species of planktonic marine ciliates. The exact origin of the chloroplast is uncertain and the periods of their retention by the protozoa is unknown. The 2 ciliate species may function partially or fully as primary producers. In other ciliates algal eye‐spots are retained and may actually be utilized. Ecologic and evolutionary implications of the observations are discussed.
East Coast Fever of Cattle: 60Co Irradiation of Infective Particles of Theileria parva
Authors: CUNNINGHAM M. P. , BROWN C. G. D. , BURRIDGE M. J. , MUSOKE A. J. , PURNELL R. E. , DARGIE J. D.
Published: May 2007

SYNOPSIS. Infective particles (IPs) of Theileria parva, the causative organism of East Coast Fever of cattle, were harvested from the tick vector, Rhipicephalus appendiculatus, using an in vitro feeding technic. In a ranging experiment, pairs of cattle were inoculated with aliquots of suspensions of IPs irradiated at doses of 4–137.6 krad. Doses of irradiation in excess of 8 krad appeared to destroy the parasite. In the 2nd and 3rd experiments, groups of 5 cattle were inoculated with aliquots of suspensions containing low and high concentrations of IPs respectively, irradiated at doses of 4–32 krad. In the 2nd experiment, doses of irradiation in excess of 10 krad appeared to destroy the parasite. In the 3rd experiment, at least 1 animal became infected when inoculated with an aliquot of a suspension irradiated at 16 krad. In all experiments, it appeared that increasing doses of irradiation destroyed increasing numbers of IPs. There was no conclusive evidence that IPs which survived irradiation were attenuated, and it appears that vaccination of cattle against ECF is unlikely to be achieved by inoculation of irradiated IPs using the methods described.
The Effects of Actinomycin D, Gibberellin A7, and Cyclic AMP on Mating of Chlamydomonas reinhardtii*
Authors: GREENWOOD HELEN L.
Published: May 2007

SYNOPSIS. Gibberellin A7 and cyclic AMP increased mating efficiency of Chlamydomonas reinhardtii when the cells were treated during gametogenesis. No change in mating activity was observed when cells were treated with 5′‐AMP. Actinomycin D inhibited both normal mating and gibberellin‐stimulated mating.
Localisation Intracellulaire et Caracterisation de Deux Types de Malate Deshydrogénase chez Trichomonas vaginalis Donné, 1836
Authors: METENIER G. BRUGEROLLE et G.
Published: May 2007

RESUME. Deux formes d'activité malate‐deshydrogénasique (MDH) ont été séparées après centrifugation en gradient de densité, chez Trichomonas vaginalis: une forme est soluble et l'autre est liée aux “grains denses'’cytoplasmiques. Ces 2 MDH (NAD dépendantes) ont des pH d'activité optimale et des constantes de Michaelis différents; on peut les séparer par électrophorèse sur gel d'amidon ou de polyacrylamide (présence d'isoenzymes).

SYNOPSIS. Two forms (isozymes) of malate dehydrogenase (MDH) of Trichomonas vaginalis cells were isolated by centrifugation on sucrose density gradient. One form is located in the soluble fraction and the other is linked to the cytoplasmic “dense granules.”

The optimum pH and Km values are different for the 2, NAD‐dependent dehydrogenases, which can be separated by starch or polyacrylamide gel electrophoresis.
Eigenschaften des Elektronentransportsystem von Mitochondrien des Protisten Acanthamoeba castellanii Neff. I. Zum Einfluß von Hemmstoffen auf verschiedene Akzeptorsysteme, getested mit einer modifizierten Thunbergtechnik
Authors: FOUQUET H.
Published: May 2007

ZUSAMMENFASSUNG. Die Reduktionsgeschwindigkeit künstlicher Elektronenakzeptoren wurde mittels einer modifizierten Thunbergtechnik in Gegenwart isolierter Mitochondrien des Protisten Acanthamoeba castellanii Neff photometrisch gemessen. Die mit verschiedenen Elektronenakzeptoren und Atmungsketteninhibitoren gewonnenen Meßergebnisse erlauben uns folgendes Bild von der Konstitution der Atmungskette zu entwerfen: a) Der Elektronentransport läuft mindestens bis zum Cytochrom b/Coenzym Q‐Komplex auf zwei verschiedenen Wegen ab. b) Eine Stimulierung sowohl des Succinat‐Jodnitrotetrazolium‐chlorid als auch des NADH‐Ferricyanid Reduktasekomplexes unter dem Einfluß von Antimycin A läßt vermuten, daß in der Atmungskette dieses Protisten gewisse Nebengleise des Elektronentransports besonders gangbar sind.

SYNOPSIS. The reduction of artificial electron acceptors by isolated mitochondria of Acanthamoeba castellanii was measured by a modified Thunberg technic. The results with different electron acceptors and respiratory chain inhibitors suggest the following scheme for the constitution of the respiratory chain: a) the chain is divided into 2 different sequences, at least up to the cytochrome b/coenzyme Q complex. b) As seen from the stimulation of the succinate‐iodonitrotetrazolium chloride and NADH‐ferricyanide reductase complexes by antimycin A, certain alternate pathways of electron transport become more important than the normal one.
Growth Phase and the Number of Phosphorylation Sites in the Mitochondrial Electron Transport Chain of Acanthamoeba castellanii
Authors: EVANS D. A.
Published: May 2007

SYNOPSIS. Mitochondria isolated from the soil ameba Acanthamoeba castellanii growing exponentially on complex medium have rotenone‐insensitive oxygen uptake and ADP:O ratios which indicate the presence of only 2 phosphorylation sites in the electron transport chain. Stationary phase amebae yield mitochondria which are sensitive to inhibition by rotenone when respiring NAD+‐Minked substrates and have 3 sites of phosphorylation. The levels of cytochromes (a +a3), b, and c are similar in mitochondria isolated from log or stationary phase amebae, and, with the exception of succinate, the respiratory rates obtained with different substrates do not change significantly from log to stationary growth phase.
Carotene Wax Pigments in the Foraminiferan Allogromia laticollaris Arnold
Authors: SCHWAB DIETER , SCHLOBACH HEINRICH
Published: May 2007

SYNOPSIS. It is evident from the results obtained by UV spectroscopy and chemical analyses that the pigments of the foraminiferan Allogromia laticollaris are carotene waxes of the xanthophyll type. Since none of the pigments was found in the food organisms, one can exclude the possibility that these pigments are derived from food. The origin of the pigments is discussed.