bluuebunny/crossref_metadata_2025 huggingface dataset:
Replication of Nosema Algerae In Three Insect Cell Lines
Authors: STREETT D. A. , RALPH DAVID , HINK W. F.
Published: May 2007

SYNOPSIS Nosema algerae, a microsporidan parasite of anopheline mosquitoes, was successfully replicated in 3 insect cell culture lines: Trichoplusia ni (TN‐368); Heliothis zea (IPLB‐1075); and Mamestra brassicae (IZD‐Mb‐0503). Infectious spores were produced in vitro. Spores were observed at 48 h postinfection, and some cells were filled with sproes by 72 h.

The number of parasites per cell increased with time. At 72 h postinfection, the infection rates for the 3 cell lines ranged from 23 to 32%. Infected cell lines were subcultured, and by the 6th passage spore production had ceased.
Cryptobia Sp. In the Snail Triadopsis Multilineata (Say): Fine Structure of Attached Flagellates and Their Mode of Attachment to the Spermatheca*
Authors: CURRENT WILLIAM L
Published: May 2007

SYNOPSIS. A Cryptobia sp. that appears to differ structurally from Cryptobia helicis Leidy occurred as 2 distinct populations within the spermatheca of the land snail Triadopsis multilineata (Say). Attached flagellates were a resident population within the spermatheca while pleomorphic, free‐swimming forms were a transient population moving freely within the reproductive tract. Slender, free‐swimming flagellates were apparently the ones transmitted by a venereal route. It was observed by electron microscopy that attachment was achieved through an extensive morphologic transformation of the first 5 to 10 μm of the anterior flagellum which resulted in the formation of numerous pseudopodium‐like structures (“flagellapodia”) capable of invading the microvillus border of the host tissue. Flagellapodia were delimited by a single unit membrane, contained granular cytoplasm, and were long, branched, finger‐like structures which interdigitated extensively with host cell microvilli. Fine structure of the Cryptobia sp. is distinctly different from that reported for C. helicis. the differences include structure and position of the preoral ridge, the cytostome‐cytopharynx, the recurrent flagellum, and the presence of the flagellapodia.
Aerial Sorocarp Development By the Aggregative Ciliate, Sorogena Stoianovitchae*
Authors: OLIVE L. S. , BLANTON R. L.
Published: May 2007

SYNOPSIS. Sorogena stoianovitchae Bradbury & Olive, an epiphytic ciliate found in various parts of the world, has a trophic stage that feeds on members of the ciliate genus Colpoda. When grown in the presence of the food ciliate, it multiplies rapidly. When the cells become abundant they aggregate at the water surface on inserted plant fragments or floating pollen grains, the sides of culture dishes, or on floating films such as those deposited by bacteria or pollen grains. an aggregate mounds up and becomes ensheathed above the water level, after which the mass of cells called a sorogen rises aerially at the apex of a stalk deposited at its base. the tapering, noncellular stalk consists of a conspicuously furrowed sheath that encloses a mucilaginous matrix. At completion of stalk development the cells of the sorogen become encysted. the sorocysts are commonly discharged by fracturing of the drying sorus. Alternating light and dark conditions are required for sorocarp development.
Long‐Term Maintenance of Tetrahymena Spp.
Authors: WILLIAMS NORMAN E. , WOLFE JASON , BLEYMAN LEA K.
Published: May 2007

SYNOPSIS. Simple media for Tetrahymena, using rat gut or soybean as the nutrient source are described. Cultures can be maintained in these media up to one year at room temperature.
Proteins and Polysaccharides In the Nutrition of Paramecium Multimicronucleatun
Authors: JOHNSON W. H. , BRENNAN M. D. , BERARD D. K. , MORROW J. H. , HUDSON K. D.
Published: May 2007

SYNOPSIS. Paramecium multimicronucleatum has been cultured for 20 years on a medium of salts, vitamins, amino acids, fatty acids, ribosides, and stigmasterol plus a little nondialyzable fraction (NDF) of baker's yeast. Fractionations of NDF identified 2 essentials: (a) in a fraction < 100,000 daltons which contained much protein and replaceable by ovalbumin and (b) in a fraction of < 300,000 daltons; this fraction contained much polysaccharide, replaceable by glycogen, which is > 300,000 daltons. For 2 years now P. multimicronucleatum has grown well with ovalbumin and glycogen replacing NDF. Besides ovalbumin, concanavalin A satisfies the protein requirement; this lectin attaches to sugar residues in glycogen. Studies with a fluorescent dye, PGA‐1A, a stilbene derivative, provides further evidence for the polysaccharide requirement. This dye attaches to polysaccharides; when added to glycogen, and this in turn is added to a culture containing ovalbumin, fluorescent blue vacuoles appear within 2–3 h. When dye + glycogen were added to a culture without ovalbumin, no fluorescent vacuoles were found. A protein appears involved in formation of food vacuoles; this fits the pattern for endocytosis described in recent reviews. Besides glycogen, mannan gave good growth. Dextrin and amylopectin gave only fair growth through 7 serial transfers; glucose, maltose and amylose did not sustain growth. Strain 51 of P. tetratrelia, which grows well in NDF medium, grows well when NDF is replaced with ovalbumin and glycogen.
Rapid Growth of Acanthamoeba In Defined Media; Induction of Encystment By Glucose‐Acetate Starvation
Authors: BYERS THOMAS J. , AKINS ROBERT A. , MAYNARD BARBARA J. , LEFKEN RICHARD A. , MARTIN SCOTT M.
Published: May 2007

Defined media are described that support 14‐20 h generation times for Acanthamoeba castellanii and A. rhysodes in monolayer cultures. the media differ in minor ways from previously described media, but the growth rates are greatly improved over previously reported values. Maximum growth rates were observed for A, castellanii in a complex medium containing 21 amino acids, but near‐maximum rates could be achieved in relatively simple media containing 9 amino acids. Growth occurred with 6 amino acids, as reported by others, but generation times exceeded 30 h. Amitosis was a common problem during early subcultures in defined media, but became infrequent after repeated transfers. Synchronous encystment resulting in 70‐80% cyst formation could be induced in the defined media by glucose and acetate starvation. the rate of encystment varied with cell density at the time of starvation and was optimal at initial densities of 400‐800 amebae/mm2.
Comparison of the Surface Proteins and Glycoproteins On Erythrocytes of Calves Before and During Infection With Babesia Bovis
Authors: HOWARD RUSSELL J. , RODWELL BARRY J. , SMITH PATRICIA M. , CALLOW L. L. , MITCHELL GRAHAM F.
Published: May 2007

The surface proteins and glycoproteins on red cells from normal and Babesia bovis‐infected calf blood have been compared. Several radiolabeling probes were used to label specifically external membrane molecules which were then separated by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and identified by autoradiography or fluorography. No differences were observed among the Coomassie Blue‐stained membrane proteins of erythrocytes from individual uninfected calves. Comparison of red cells from these animals also indicated no qualitative differences in the surface proteins with accessible tyrosyl residues labeled by lactoperoxidase‐catalyzed radioiodnation, although some quantitative variation in the uptake of radioactivity into particular proteins was observed. the major radioiodinated bands on normal bovine erythrocytes had Mr of 165, 130, 90, and 45 kiloDaltons. However, labeling of surface glycoproteins by the periodate/[3H]NaBH4 and galactose oxidase (± neuraminidase)/[3H]NaBH4 methods showed significant differences in the surface proteins of red cells from individual uninfected calves. of 14 animals tested, 5 had major labeled glycoproteins of unique Mr. No changes were observed in radioiodinated surface proteins of total red cell samples from infected calves with 0.5‐6% parasitemia. Radioiodination of concentrated infected red cells from the same samples (concentrated by selective hypotonic lysis of uninfected erythrocytes in KC1) resulted in the labeling of 3 new surface proteins, with Mr of 118, 115, and 60 kiloDaltons. the same new 125I‐labeled bands were identified on infected cells from 3 avirulent strains of B. bovis used in vaccine production. Furthermore, in concentrated infected cells there was very poor radiolabeling of major bands strongly labeled on uninfected cells (Mr 165, 130, and 90 kiloDaltons), suggesting parasite‐induced loss of these proteins. Although there were some differences in 3H‐labeled surface glycoproteins of red cells from normal and. B. bovis ‐infected blood, they were restricted to minor labeled bands and were not seen consistently. the labeled surface glycoproteins of concentrated infected cells were very similar to those of the uninfected red blood cells from infected blood.
On the Taxonomic Status of the Family Pfeifferinellidae (Coccidia), with a Description of Pfeifferinella gugleri sp. n.
Authors: WACHA RICHARD S.
Published: May 2007

SYNOPSIS. Pfeifferinella gugleri sp. n. was found in the liver of each of 2 land snails, Triodopsis albolabris (Say), in Iowa. The stages found, their average length × width dimensions (in μm), and their principal features were as follows: oocysts (21 × 14.5) ovoid, with micropyle and oocyst residuum; meronts (20 × 15) with 24–32 merozoites: microgametocytes (15 × 11.5) with many small microgametes; macrogametes (20 × 10.5) with 1–5 nucleoli and 1–2 wall‐forming bodies, but without a “vaginal [fertilization] tube.” This tube, originally described by Léger & Hollande, 1912, from Pfeifferinella impudica, has since been considered a principal taxonomic feature of the family Pfeifferinellidae. In the absence of this structure, the taxonomic status of this monogeneric family is reexamined with the recommendation that the family be retained as distinct, but redefined to exclude the “vaginal tube” as a valid characteristic. The discovery of P. gugleri brings to 3 the number of pfeifferinellids reported, the other 2 being P. impudica Léger & Hollande, 1912, and P. ellipsoides Wasielewski, 1904, all from gastropods.
Binding of Lectins to the Cell Surface of Trypanosoma cruzi*
Authors: ARAUJO FAUSTO G. , HANDMAN EMANUELA , REMINGTON JACK S.
Published: May 2007

SYNOPSIS. Differences in the composition and distribution of cell membrane carbohydrates were demonstrated in the 3 life cycle forms of 3 Trypanosoma cruzi strains by using lectins with different specificities. The results suggest that lectin binding may be useful in characterization of the parasite strains.
Content, Synthesis, and Function of Polyamines in Trypanosomatids: Relationship to Chemotherapy1,2
Authors: BACCHI CYRUS J.
Published: May 2007

Polyamines are multiply amine‐substituted straight‐chain aliphatics; their content in different tissues may vary widely, and their functions are many. Their main routes of biosynthesis originate from ornithine and methionine. Polyamine content and biosynthesis in tryposomatid flagellates are reviewed concluding with emphasis on their possible role as critical drug targets in these parasitic protozoa so pathogenic for man in large areas of the world.
Particle Assemblies in the Plasma Membrane of Tetrahymena: Relationship to Cell Surface Topography and Cellular Morphogenesis1
Authors: HUFNAGEL L. A.
Published: May 2007

During a freeze‐fracture electron microscopical study of the plasma membrane of Tetrahymena, several different types of organized particle assemblies were observed. Three of these were found only on the protoplasmic face and were localized in the anterior‐ventral region of the cell. These consisted of plate‐like arrays composed of 4–25 triplet rows of small 3–4 nm particles; long, paired linear arrays localized at the tops of cortical ridges and composed of 7–8 nm particles; and elongated tetragonal arrays located in the grooves between ridges and composed of approximately 10 nm particles. The distribution of these arrays is consistent with roles in cellular morphogenesis, chemoreception, or cell‐cell pairing during conjugation. In addition, a unique particle track associated with the cytoproct (anal pore) was observed in the external face of the plasma membrane. Furthermore, the protoplasmic face of the plasma membrane is characterized by a high density of particles organized into localized microarrays, consisting of small paracrystals or strings, which exhibit a loose higher‐order patterning most evident toward the anterior end of the cell. Particle distributions on the protoplasmic face do not appear to be significantly altered by conditions that cause clumping of alveolar membrane particles. Taken together, these observations are consistent with the idea that the proteins of the plasma membrane are highly ordered and relatively immobile and that the structure of the plasma membrane is regionally differentiated.
Isospora as an Extraintestinal Parasite of Passerine Birds1
Authors: BOX EDITH D.
Published: May 2007

Toxoplasma‐like avian parasites inhabiting mononuclear phagocytes have been called Haemogregarina, Toxoplasma. avian Toxoplasma, Atoxoplasma, and Lankesterella by various authors. My attempts to transmit the parasites by bloodsucking mites or by transfer of blood and tissues of infected sparrows and canaries were unsuccessful. However, it was noted that the infection was exacerbated under conditions that favored transmission of coccidiosis: crowding and lack of cleanliness. Oral inoculation of sporulated oocysts of Isospora resulted in death from overwhelming macrophage infection with Toxoplasma‐like organisms. Experiments using sparrows and canaries showed that the Isospora species involved was not cross infectious. Further investigations using canaries demonstrated that after oral oocyst inoculation, infection of macrophages spread from the submucosa of the duodenum to the liver. spleen, and lungs. After several generations in the internal organs, asexual multiplication, occured in the intestinal epithelium of the small intestinc. Fecal oocysts first appeared at the end of 9–10 days. Oocysts continued to be passed in the feces for months after infection. This chronicity may be explained by the relatively long life of the macrophages that serve as host cells for the asexual stages as compared to the intestinal epithelium which is the cell type parasitized by conventional coccidia.
A Comparative Study of the Infraciliature and Silverline System of the Fresh‐Water Scuticociliates Pseudocohnilembus putrinus (Kahl, 1928) nov. comb., P. pusillus (Quennerstedt, 1869) nov. comb., and the Marine Form P. marinus Thompson, 19661
Authors: FOISSNER WILHELM , WILBERT NORBERT
Published: May 2007

Three species of Pseudocohnilembus were examined with respect to infraciliature and the silverline system. The freshwater species P. putrinus and P. pusillus exhibited no differences in general organization of the argyrophilic structures when compared with the marine P. marinus. A review of the Pseudocohnilembus species that have been described on the basis of silver preparations shows that at present four species have been well characterized: P. pusillus (Quennerstedt, 1869) nov. comb., P. putrinus (Kahl, 1928) nov. comb., P. hargisi Evans & Thompson, 1964, and P. marinus Thompson, 1966, P. persalinus Evans & Thompson, 1964 and P. longiseta Evans & Thompson, 1964 are regarded as identical with the older known P. pusillus, because with respect to morphology and argyrophilic structures they are within the range of variability of that species; and their names thus fall as synonyms of P. pusillus.
Characterization of Populations of Promastigotes of Leishmania donovani1
Authors: DORAN THOMAS I. , HERMAN ROBERT
Published: May 2007

Promastigotes of Leismania donovani cultured for either 3 or 10 days in vitro and inoculated intracardially into golden hamsters with an equal number of organisms from either population showed a 7‐fold difference in infectivity when compared at both 10 to 16 days post‐infection. Reproducible histochemical staining for the promastigote enzymes glucose‐6‐phosphate dehydrogenase (G6PDH) and peptidase after polyacrylamide gel electrophoresis showed two isoelectric variants of G6PDH (Bands 1 and 2) that displayed a 45% decrease (Band 1) and a 60% increase (Band 2) in total activity when 3‐ and 10‐day‐old promastigores were compared. Peptidase activity, present in a single band, increased 7‐fold in 10‐day‐old promastigotes. A decrease in the lectin‐induced agglutination of promastigotes by castor bean agglutinin (RCA60), specific for D‐galactose and N‐acetyl‐D‐galactosamine, was seen when 3‐ and 10‐day‐old promastigotes are compared. Antisera raised against sonicated 10‐day‐old promastigotes showed a unique precipitin band between the antiserum and sonicated 10‐day‐old promastigotes not found between the antiserum and sonicated 3‐day‐old promastigotes.
Five New Species of Myxobolus (Myxosporea: Protozoa), Parasitic in Cirrhina mrigala (Hamilton) and Labeo rohita (Hamilton), with a Note on a New Host Record for M. curmucae Seenappa & Manohar, 19801
Authors: SEENAPPA D. , MANOHAR L.
Published: May 2007

Five new species of the genus Myxobolus (Myxosporea) infecting the fresh‐water carps are described. M. bhadrensis n. sp. was noticed in the musculature of the fry of Labeo rohita, collected from Bhadra Fish Seed Farm, in September 1979; and M. shettii, M. vedavatiensis, M. venkateshi, and M. hosadurgensis n. spp. were found in the gills of Cirrhina mrigala sampled from Vanivilasa Sagar Fish Farm in April 1980. Also, a new host record for M. curmucae is reported.
Some Corrections in Haemogregarine (Apicomplexa: Protozoa) Nomenclature1
Authors: LEVINE NORMAN D.
Published: May 2007

The nomenclature of three genera in the family Haemogregarinidae (Haemogregarina, Karyolysus, and Hepatozoon) has been reviewed and the following new names are introduced to replace homonyms or for previously unnamed species: Haemogregarina carlosi n. nom., in the erythrocytes of the lizard Lacerta ocellata; Haemogregarina tincae n. nom., in the stomach and intestine of the tench Tinca tinca; Hepatozoon insectivorae n. sp., in the leucocytes of the shrews Sorex araneus and Crocidura leucodon; Hepatozoon krampitzi n. sp., in the leucocytes of the vole Microtus oeconomus; Hepatozoon peromysci n. sp., in the leucocytes of the deermice Peromyscus boylii and P. truei gilberti; and Hepatozoon pallida (Pessoa et al., 1971) n. comb., in the erythrocytes of the snake Thamnodynastes pallidus nattereri.
X‐ray Microanalysis of the Mineral Contents of Some Protozoa
Authors: RIEDER NORBERT , OTT HUBERT A. , PFUNDSTEIN PETER , SCHOCH ROBERT
Published: May 2007

With the aid of energy‐dispersive X‐ray microanalysis, several protozoa were tested for content of cations within inorganic minerals. The skeleton of acantharia consists mainly of Sr with small quantities of Ca and Ba. Two Loxodes species contain nothing but Ba, while in some Remanella species Sr with small quantities of Ba were present. In one Geleia species, Ca with small quantities of Sr was found; in two Trachelocerca species from Sylt (Germany), Ba is there in addition. Another Trachelocerca species from northern Italy lacked Ba, but did possess Mn. In Prorodon only Ca was found.
Ultrastructure, Behavior, and Algal Flagellate Affinities of the Helioflagellate Ciliophrys marina, and the Classification of the Helioflagellates (Protista, Actinopoda, Heliozoea)1
Authors: DAVIDSON LLOYD A.
Published: May 2007

Ciliophrys marina is a small marine helioflagellate, with a central nucleus, which is capable of reversibly transforming from a rapidly swimming flagellate cell with no axopodia to the structure of a heliozoan with a flagellum that beats only a few times a minute. When in the flagellate form, the flagellum acts as a tractellum due to the tubular mastigonemes found along its length. When the rapidly swimming flagellate strikes a piece of debris, the flagellum goes through a very characteristic shock‐induced avoidance reaction. Similarly, when a mechanical shock is delivered to the cell in its heliozoan form, the axopodia are contracted in less than 20 msec. Both reactions are inhibited in low calcium seawater. Transformation from the heliozoan to the flagellate form is accomplished by slow retraction and absorbance of the axopodia and activation of the flagellum. Ultrastructurally, each axopodium is found to contain three microtubules which attach to the outer nuclear membrane of the central nucleus at sites that this study characterizes by electron microscopy of thin sections and freeze fracture preparations. The mitochondria have tubular cristae, each containing an intracristal filament. Finally, a taxonomic review of the helioflagellates is presented, and it is suggested that C. marina is derived from the chrysomonads. An argument is also made for classifying C. marina with the heliozoan order Actinophryida, as a recently published classification of the protozoa does.
Kinetic Analysis of Chemokinesis of Paramecium1
Authors: HOUTEN JUDITH VAN , MARTEL ELAINE , KASCH TONYA
Published: May 2007

Paramecia detect and accumulate in or disperse from some chemicals. Cells do this by changing frequency of turning and speed of swimming. There are at least two mechanisms by which cells respond: one dependent on ability to turn, one dependent on speed modulation. There are also two classes of chemicals: those that require the cells' ability to turn in order to cause accumulation and dispersal (type I), and those that apparently require only speed modulation (type II). Attractants of type I cause qualitatively similar changes in behavior to repellents of type II and the converse; therefore, assays are needed to distinguish between these two classes of chemicals, despite qualitatively similar behavior of some attractants and repellents. We examined two assays of paramecium chemoresponse, T‐maze assay and well test, to understand how the T‐maze distinguishes between attractants of type I and repellents of type II and why the well test does not.
Tritrichomonas foetus: Fine Structure of Freeze‐Fractured Membranes1
Authors: BENCHIMOL MARLENE , ELIAS CEZAR ANTONIO , DE SOUZA WANDERLEY
Published: May 2007

ABSTRACT. Freeze‐fracture techniques reveal differences in fine structure between the anterior three flagella of Tritrichomonas foetus and its recurrent flagellum. The anterior flagella have rosettes of 9–12 intramembranous particles on both the P and E faces. The recurrent flagellum lacks rosettes but has ribbon‐like arrays of particles along the length of the flagellum, which may be involved in the flagellum's attachment to the cell body. This flagellum is attached to the membrane of the cell body along a distinct groove that contains few discernible particles. Some large intramembranous particles are visible on the P face of the cell body membrane at the point where the flagellum emerges from the cell body. The randomly distributed particles on the P and E faces of the plasma membrane have a particle density of 919/μm2 and 468/μm2 respectively, and there are areas on both faces that are devoid of particles. Freeze‐fracture techniques also reveal numerous fenestrations in the membrane of the Golgi complex and about 24 pores per μm2 in the nuclear. membrane.
Development of the Ciliary Pattern of the Oral Apparatus of Tetrahymena thermophila1
Authors: BAKOWSKA JULITA , NELSEN E. MARLO , FRANKEL JOSEPH
Published: May 2007

ABSTRACT. The sequence of formation and ciliation of basal bodies and the subsequent organization of compound ciliary structures of the oral apparatus of Tetrahymena thermophila was reanalyzed with the aid of scanning electron microscopy of cells in which the epiplasmic layer was exposed, as well as by light microscopy of protargol‐impregnated specimens. This combination of methods allowed the delineation of numerous steps in the patterning of the oral ciliature, some of which have received little or no previous attention. Highlights include: the initial formation of “strings” of nonciliated new basal bodies in juxtaposition to relatively few basal bodies of the stomatogenic kinety; generation of basal body pairs, roughly oriented along the anteroposterior axis of the cell, that later align side‐by‐side to assemble promembranelles; condensation and reorientation of promembranelles simultaneous with addition of a third row of basal bodies anterior to the original two rows; production of a very short fourth row of basal bodies at the anterior right end of each developing membranelle; generation of the outer basal body row of the undulating membrane (UM) after alignment of the inner row, with transient ciliation of the inner row preceding permanent ciliation of the outer row; limited basal body resorption at the ends of membranelles; and sculpturing of the right ends of membranelles by a movement of basal bodies associated with formation of the ribbed wall adjacent to the UM. In the old anterior oral apparatus a repetition of the processes of generation of a new outer UM row and sculpturing of right ends of membranelles takes place in synchrony with the corresponding events in the oral primordium, following prior shedding of the old outer UM row and loss of the sculptured pattern in association with temporary regression of the ribbed wall micro‐tubules. Oral development is complex, with different processes involved in the assembly of the membranelles and the UM, and with a sequence of distinct events involved in the generation of each of these structures. Speaking comparatively, membranelle development follows the same pathway in many, perhaps all, ciliates in which these structures or their homologues develop from a common stomatogenic field.
The Correlation of Digestive Vacuole pH and Size with the Digestive Cycle in Paramecium caudatum1
Authors: FOK AGNES K. , LEE YENG , ALLEN RICHARD D.
Published: May 2007

ABSTRACT. The temporal changes in the size and pH of digestive vacuoles (DV) in Paramecium caudatum were reevaluated. Cells were pulsed briefly with polystyrene latex spheres or heat‐killed yeast stained with three sulfonphthalein indicator dyes. Within 5 min of formation the intravacuolar pH declined from ∼7 to 3. With the exception of a transient and early increase in vacuolar size, vacuole condensation occurred rapidly and paralleled the acidification so that vacuoles reached their lowest pH and minimal size simultaneously. Neutralization and expansion of vacuole size began when vacuoles were GT8 min old. No labeled vacuoles were defecated prior to 21 min after formation but almost all DV were defecated within 1 h so that the digestive cycle of individual vacuoles ranged from 21 to 60 min. Based on these size and pH changes, the presence of acid phosphatase activity, and membrane morphology, digestive vacuoles can be grouped into four stages of digestion. The DV‐I are GT6 min old and undergo rapid condensation and acidification. The DV‐II are between 4 to 10 min old and are the most condensed and acidic vacuoles. The DV‐III range in age from 8 to ∼20 min and include the expanding or expanded vacuoles that result from lysosomes fusing with DV‐II. The DV‐IV are GD21 min old, and since digestion is presumably completed, they can be defecated. The rise in intravacuolar pH that accompanies vacuole expansion suggests that lysosomes play a role in vacuole neutralization in addition to their degradative functions. The acidification and condensation processes in DV‐I appear to be unrelated to lysosomal function, as no acid phosphaiase activity has been detected at this stage, but may be related to phagosomal functions important in killing food organisms, denaturing proteins prior to digestion, and preparing vacuole membrane for fusion with lysosomes.
Trypanosoma cruzi: Flow Cytometric Analysis. I. Analysis of Total DNA/Organism by Means of Mithramycin‐Induced Fluorescence1,2
Authors: DVORAK JAMES A. , HALL THOMAS E. , CRANE MARK ST. J. , ENGEL JUAN C. , McDANIEL JAMES P. , URIEGAS RODOLFO
Published: May 2007

ABSTRACT. Total DNA/organism was determined by flow cytometry on stocks of 33 single‐cell‐isolate clones and one strain of mithramycin‐stained Trypanosoma cruzi. Interstrain differences in mean total DNA/group of 34% and interclone differences in total DNA/organism of 41% were found. Microspectrofluorometric analyses of the trypomastigote stage of selected clones confirmed the flow cytometry data and indicated that the total DNA/organism differences were due to differences in DNA of both the nucleus and kinetoplast with the nucleus being the major contributing factor. These data imply that the potential for genetic diversity in T. cruzi may be very large.
Direct Infection of Hepatocytes by Sporozoites of Plasmodium berghei1
Authors: SHIN SHEILA CHIC J. , VANDERBERG JEROME P. , TERZAKIS JOHN A.
Published: May 2007

ABSTRACT. To identify the unknown liver cell type initially invaded by sporozoiles of mammalian malaria, young rats were inoculated intravenously with large numbers of Plasmodium berghei sporozoites obtained from infected Anopheles stephensi mosquitoes. Fine structural studies of liver specimens obtained from the rats within 2 min after inoculation demonstrated the presence of morphologically unaltered sporozoites in the cytoplasm of hepatocytes. Many sporozoites were also observed undergoing cytolysis within the lysophagosomes of Kupffer cells, as well as other phagocytic cells. These observations strongly suggest direct infection of the hepatocyte by the sporozoite.
Conditions Favoring Gametocytogenesis in the Continuous Culture of Plasmodium falciparum1
Authors: BROCKELMAN CHARIYA R.
Published: May 2007

ABSTRACT. Gametocyte formation was observed in six isolates of Plasmodium falciparum in continuous culture. Optimal conditions include constant temperature and addition of caffeine at 2.0 mM. Depletion of glucose in the medium and treatment with cAMP did not consistently trigger the formation of gametocytes.
Early Colonization Patterns of Diatoms and Protozoa in Fourteen Fresh‐water Lakes1
Authors: CAIRNS JOHN , PLAFKIN JAMES L. , KAESLER ROGER L. , LOWE REX L.
Published: May 2007

ABSTRACT. Polyurethane substrates were anchored near the surface of 14 lakes in the northern tip of the lower peninsula of Michigan. I wo substrates were removed from each take and taken to the laboratory after 1, 3, 6, 15, and 21 days of exposure. At the laboratory, one substrate was used for determining the number of species of diatoms and the other for protozoa. A cluster analysis of the matrix of Jaccard's coefficients for all diatom samples from all lakes showed that virtually all samples from any given lake consistently clustered together. This indicates that, with respect to species occurrence, distinct and compositionally stable diatom assemblages formed on the substrates in fewer than 21 days. Analysis of all protozoan samples from all lakes did not show such clustering, however, and the correspondence of clusters for protozoan and diatom communities for the 14 lakes was not particularly good. This suggests that the link between the two groups at the species level is not particularly strong during the early phases of artificial substrate colonization.
Microtubules and Filaments Beneath the Fission Furrow of Stentor coeruleus1
Authors: DIENER DENNIS R. , BURCHILL BROWER R. , BURTON PAUL R.
Published: May 2007

ABSTRACT. The ultrastructure of the cortex beneath the fission furrow of dividing Stentor coeruleus was examined using scanning and transmission electron microscopy. During division, basal bodies, axonemes, and km fibers beneath the furrow were absorbed near the moving primordial oral apparatus, and a circumferential band of microtubules and filaments was formed at the base of the furrow. The location and orientation of this fibrous band suggest that it may be an important component of the cytokinetic machinery. Treatment with vinblastine sulfate (4 × 10‐5 M) disrupted the circumferential microtubules and blocked division, which is consistent with this hypothesis.
Lorica Construction in Eufolliculina sp. (Ciliophora, Heterotrichida)1
Authors: MULISCH MARIA , HAUSMANN KLAUS
Published: May 2007

ABSTRACT. The structure and ultrastructure of the chitinous lorica of Eufolliculina sp. are described. The lorica is produced from precursor material secreted by the motile swarmer immediately after settling. This material is located in numerous vesicles found in the cortical region of the cells and is secreted by exocytosis. Initially, material is secreted from the ventral part of the cell to produce the attachment plate of the lorica. After this, exocytosis occurs over most of the body surface as the ampulla part of the lorica is constructed. During the later stages of lorica formation, secretion is mainly limited to the anterior of the cell as the neck is formed. The lorica is shaped mainly by the action of the cilia and by the behavior of the cell. While the neck is being formed, the anterior part of the cell is deformed by a local accumulation of cytoplasmic vacuoles. This deformation is employed in shaping the neck. No changes were detected in the organization of the cortical infraciliature during the first stages of lorica formation, but they do occur after the neck has been produced and as the swarmer develops into the sessile form.
Intraspecies Variability in the Esterases and Acid Phosphatases of Four Species of the Paramecium aurelia Complex1
Authors: ALLEN SALLY LYMAN , NERAD THOMAS A. , RUSHFORD CAROLINE L.
Published: May 2007

ABSTRACT. One hundred eighty‐eight stocks of Paramecium primaurelia. P. biaurelia, P. tetraurelia. and P. octaurelia were grown axenically and screened for variation in four different esterases and acid phosphatase using starch gel electrophoresis. Major observations: frequency of intraspecies variation for these enzymes is much lower in these four species than in other organisms; hypervariability for two esterases occurs in P. biaurelia both in isolates from worldwide locales and in a restricted locale; clustering of variations occurs in a high proportion of variant stocks in all four species; frequency of intraspecies variation is highest in Central and South America for all four species; and geographical differentiation is lacking between stocks in the same species both for common as well as variant phenotypes despite the cosmopolitan distribution of these species. These results are not correlated with adaptations that favor inbreeding over outbreeding. nor is the possession of bacterial endosymbionts strongly correlated with enzyme variation. When the riequency of intraspecies variation was examined for the aurelia complex of species as a whole for 13 enzymes, mitochondrial DNA, and ribosomal DNA, differences between enzymes in frequency of variation could be seen, ranging from less than 2% for seven enzymes to 12.4% for glucosephosphate isomerase, a value similar to that observed for malic dehydrogenase, mitochondrial DNA, and ribosomal DNA in P. tetraurelia. The percentage of polymorphic enzyme loci in the complex as a whole was found to be much lower than that observed for other organisms. For the species more intensely studied in this paper the level of genetic polymorphism was also much lower, although P. biaurelia showed greater variability for two of the enzymes.
“Unidentified” Mobile Protozoans from the Blood of Carp and Some Unsolved Problems of Myxosporean Life Cycles1
Authors: LOM JIRI , DYKOVA IVA , PAVLASKOVA MILENA
Published: May 2007

Heavy infections with enigmatic mobile organisms have recently been found in the blood of carp (Cyprinus carpio) in Central Europe. The organisms measure up to 15 μm, are variable in shape, and exhibit an unceasing twitching or dancing movement. Their developmental cycle starts with a primary cell enclosing a secondary cell. The former grows while the latter produces inside itself by a series of binary fissions and internal cleavages up to eight secondary cells, each of which encloses an inner (tertiary) cell of its own. In addition, up to four tiny cells with compact nuclei (“residual bodies”) also result from divisions of the secondary cells. Primary cells containing the products of the division of secondary cells finally disintegrate, releasing the secondary cells, which in their turn become new primary cells and repeat the cycle all over again. The structure and behavior of these organisms were so incompatible with existing ideas on myxosporean development that their myxosporean affinity was at first unrecognized. The final proof of their identity–appearance of myxosporean spores in sterile, experimentally infected hosts–is still to be presented. The interpretation of the myxosporean features of their life cycle (i.e., [1] the pericyte nature of the primary cell, [2] proliferation by disintegration of the pseudoplasmodial primary cell, [3] no rigidly fixed pattern in vegetative development), their ultrastructure (i.e., [1] characteristic bundles of microtubules and numerous free ribosomes in secondary cells, [2] lack of centrioles, [3] membranes enclosing the secondary cells within the primary cells), and facts on their epizootiology (i.e., [1] no success at transmission via leeches, [2] the occurrence of these organisms along with Sphaerospora renicola Dykova and Lom) suggest that they are stages of S. renicola from the kidney of carp. Similar mobile organisms were found in the blood of fry of two other fishes (Gobio gobi and Tinca tinca) which are also hosts for a Sphaerospora that infects the kidney. This suggests that these organisms represent an early phase in the developmental cycle in the genus Sphaerospora. The existence of cells enveloped one within the other (secondary and tertiary cells) in the developmental cycle, a characteristic myxosporean feature itself, is an intriguing parallel to similarly enclosed cells in sporogenesis of Paramyxea (Ascetospora).
Life Cycle and Epizootiology of Amblyospora sp. (Microspora: Amblyosporidae) in the Mosquito, Aedes cantator1
Authors: ANDREADIS THEODORE G.
Published: May 2007

In Aedes cantator, Amblyospora sp. is transovarially transmitted and has two developmental sequences. The life cycle is initiated in the adult female with the release of sporoplasms from binucleated spores not bounded by membranes, lying free within host oenocytes. Sporoplasms infect the developing oocytes and are transmitted to the filial generation when the eggs are laid. In some of the female progeny that hatch from infected eggs, diplokaryotic cells infect host oenocytes and divide by binary fission during merogony. Sporulation and spore formation do not occur until a blood meal is taken by the host and they coincide with the development and maturation of the oocytes to complete the cycle. In other female and all male progeny, pathogen development occurs within fat body tissue of the host where diplokaryotic cells divide by multiple fission during merogony to spread the infection. Sporulation in this developmental sequence is characterized by the secretion of an accessory membrane and the meiotic division of diplokaryotic sporonts, which result in the formation of octonucleated plasmodia that undergo cytokinesis to form eight haploid spores which are not perorally infectious to other mosquito larvae. There is no increase in the prevalence of either type of infection in field populations during juvenile development, indicating that there is no direct horizontal transmission of the pathogen within any one generation. Data obtained from laboratory rearings of infected progeny, however, show that infections cannot persist relying solely upon maternal‐mediated transmission and that some other mode of transmission must be operative for continued maintenance of this microsporidium in A. cantator.
Morphology and Morphogenesis of Fuscheria terricola n. sp. and Spathidium muscorum (Ciliophora: Kinetofragminophora)1
Authors: BERGER HELMUT , FOISSNER WILHELM , ADAM HANS
Published: May 2007

The morphology and morphogenesis of the kinetofragminophoran soil ciliates, Fuscheria terricola n. sp. and Spathidium muscorum Dragesco & Dragesco‐Kerneis, 1979, are described. Stained specimens (protargol) are characterized biometrically. The new species differs from the other species of the genus in its body size, body shape, number of kineties, length of extrusomes, and habitat. Both species have telokinetal stomatogenesis, which commences with a proliferation of kinetosomes at those kineties which bear the brosse. Fuscheria terricola does not have a complex perioral ciliature; indeed, it might be that this species has only monokinetids. Thus only a proliferation of kinetosomes and the separation of the kineties takes place in the prospective division furrow. In contrast, S. muscorum differentiates short dikinetid kinetofragments in the region of the division furrow, which are arranged to form the perioral kinety of the opisthe in the intermediate and late stages of the stomatogenesis. The right part of the perioral kinety develops first. This and other studies show that telokinetal stomatogenesis proceeds very differently depending on the differentiation of the oral ciliature; however, detailed studies on the morphogenesis of kinetofragminophoran ciliates are still too few in number for subtypes to be defined.
The Genera Barrouxia, Defretinella, and Goussia of the Coccidian Family Barrouxiidae (Protozoa, Apicomplexa)1
Authors: LEVINE NORMAN D.
Published: May 2007

The apicomplexan family Barrouxiidae Léger, 1911 is reviewed and revised on the basis of present information. It includes the genera Barrouxia Schneider, 1885 with ten named species, Defretinella Henneré, 1966 with one named species, and Goussia Labbé, 1896 with 25 named species. The family is characterized by having bivalved sporocysts with a longitudinal suture line. Available information, admittedly spotty, is given for each species on oocyst, sporocyst and sporozoite structure, and on locus of sporulation. The following seven new combinations are made: Goussia flaviviridis (Setna & Bana, 1935) n. comb. in the gecko Hemidactylus flaviviridis; G. hyalina (Léger, 1898) n. comb. in an unidentified aquatic beetle; G. lacazei (Labbé, 1895) n. comb. in the centipedes Lithobius forficatus and L. martini; G. metchnikovi (Laveran, 1897) n. comb. in the gobies Gobio gobio and G. albipinnatus; G. schaudinniana (Pinto, 1928) n. comb. in the centipede Lithobius forficatus; G. stankovitchi (Pinto, 1928) n. comb. in the small bleak Alburnus alburnus, the bream Abramis brama, and the red roach Scardinius erythrophthalmus; Goussia sp. (Dogel' Akhmerov, 1959) nov. comb. in the freshwater fish Gnathopogon chankaensis.
Ultrastructural Localization of Monoclonal IgG Antibodies for Antigenic Sites of Eimeria tenella Oocysts, Sporocysts, and Sporozoites1
Authors: SPEER CLARENCE A. , WONG ROSIE B. , SCHENKEL ROBERT H.
Published: May 2007

Monoclonal IgG antibodies against sporozoites of Eimeria tenella were obtained from the ascites fluid of BALB/c mice. Oocysts, sporocysts, and sporozoites were exposed to medium 199, normal ascites fluid, or monoclonal antibodies 1A, 9D, 3D3II, or 2G8f. Specimens were then incubated with ferritin‐conjugated goat anti‐mouse IgG antibody. Ferritin was uniformly distributed over the surface of sporozoites exposed to 1A, 9D, or 3D3II; ferritin was localized in patches on sporozoites exposed to 2G8f. A uniform layer of ferritin was present on the inner layer of oocyst walls and on the Stieda body and outer surface of sporocysts exposed to 1A, 9D or 3D3II. In specimens treated with 2G8f, ferritin was present on the inner layer of the oocyst wall and the Stieda body, but not on the sporocyst wall. No ferritin was found on specimens exposed to medium 199 or normal ascites fluid. Monoclonal antibodies 1A, 9D, and 3D3II, but not 2G8f, caused complement‐mediated lysis of sporozoites. These findings indicate that oocysts, sporocysts, and sporozoites of E. tenella contain common antigens specific for each monoclonal antibody tested.
Patterns of DNA Synthesis and Cell Division in Marine Dinoflagellates1
Authors: KARENTZ DENEB
Published: May 2007

Changes in mean cell size, DNA and cell density were monitored at 6‐h intervals for 72 h in populations of six species (eight clones) of marine dinoflagellates to determine the temporal relationships between the cell cycle events of DNA replication and cytokinesis. Batch cultures were maintained at 15 or 20°C on a 12‐h light: 12‐h dark photoperiod. Cell densities and size frequency distributions were determined conductimetrically and the amount of DNA within populations was measured fluorometrically. A variety of intra‐ and interspecific relationships were observed, ranging from parallel phasing of cell cycle processes to variations which involved the temporal uncoupling of DNA synthesis from the phased pattern of cell division which is characteristic of dinoflagellate cell cycles. Daily growth rates of individual populations varied from 0.05 (Gymnodinium nelsoni) to 2.08 (Amphidinium carteri) cell divisions day‐1and DNA doubling rates ranged from 0 to 1.14 day‐1. Mean doubling rates for DNA were usually 30–40% lower than those for cells. The degree of difference in these rates and the amount of variability evident in cell cycle sequences may be major factors in determining the rate and extent of development of dinoflagellate populations in nature.
Nuclease Digestion of Chromatin from the Eukaryotic Algae Olisthodiscus luteus, Peridinium balticum, and Crypthecodinium cohnii1, 2
Authors: SHUPE KATHLEEN , RIZZO PETER J.
Published: May 2007

Chromatin from a uninucleate dinoflagellate, Crypthecodinium cohnii, a binucleate dinoflagellate, Peridinium balticum, and a chromophyte, Olisthodiscus luteus, was examined by nuclease digestion and the results were compared to those from vertebrates. Gel analysis of the products of staphylococcal (micrococcal) nuclease digestion revealed a DNA repeat unit of 220(±5) base pairs for O. luteus and 215(±5) for P. balticum. Limit digestion gave a core particle of 140 base pairs, revealing that these longer repeat sizes are due to longer linker regions. No repeating subunit structure was found upon electrophoresis of digests of C. cohnii nuclei. Examination of the DNA fragments produced by DNAse I digestion of nuclei isolated from P. balticum and O. luteus showed the same ladder of ten base multiples as seen in chromatin from other eukaryotes. Examination of the kinetics of digestion by DNAse II of Peridinium chromatin revealed less susceptibility when compared to DNAse I digestions while 70% of Olisthodiscus chromatin and 35% of C. cohnii chromatin was sensitive to DNAse II. These data, taken together with previous results from Euglena, indicate that while algal chromatin is similar to that of higher eukaryotes in regard to DNAse I and II action, it differs in that the linker DNA is longer. In addition, the Hl‐like histone from O. luteus and P. balticum is located in the linker DNA as in higher eukaryotes.
Regulation of Ribosomal RNA Transcription During Differentiation of Acanthamoeba castellanii: A Review
Authors: PAULE MARVIN R.
Published: May 2007

During the cellular differentiation induced by starvation of Acanthamoeba castellanii, the expression of a number of genes is regulated. Evidence is reviewed that at least one of these, the precursor ribosomal RNA transcription unit, is regulated at the level of transcription. The structure of the rRNA transcription unit and of the RNA polymerases responsible for transcription in Acanthamoeba are reviewed. Utilizing an in vitro transcription system constructed from these components, preliminary evidence has been obtained that pre‐rRNA gene expression is regulated by a modification of RNA polymerase I that affects the enzyme's ability to participate efficiently in the initiation of transcription. These results are reviewed in relation to other known mechanisms of transcriptional regulation in eukaryotes.