摘要:

ABSTRACTAscogregarina saraviaen. sp. (Apicomplexa: Lecudinidae) is described from wild‐caughtLutzomyia lichyi(Diptera: Psychodidae) females. Gametocysts adhered to the hemocoel side of the genital accessory gland walls and oocysts were injected into their lumina. Sporulated oocysts were ellipsoidal, 12.4 × 5.8 (11.6–13.1 × 5.6–5.9) micrometers, contained eight sporozoites and a refractile residuum. The elongate form ofA. saraviaen. sp. oocysts, and their more delicate walls, clearly distinguish them from oocysts ofA. chagasi(Adler&Mayrink

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05872.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTThe complete life cycle ofAmblyospora campbelli(Kellen and Wills, 1962) (Microsporida: Amblyosporidae) requires a two‐host system involving the mosquito host,Culiseta incidens(Thomson), and an obligatory intermediate copepod host. The parasite has dimorphic spore development producing meiospores (haploid condition) and binucleated spores (diploid condition), either as an exclusive infection or simultaneously (within females only). This is the 1st known report of concurrent spore development within an adult mosquito host, and, therefore, shows theAmblyospora campbellisystem to be uniquely different from otherAmblyosporaspp. cycles previously described. The significance of dimorphic spore development is discussed. In females, diplokaryotic meronts may invade oenocytes, causing a benign‐type of infection. A blood‐meal is required to initiate sporulation of the binucleate spore. The binucleate spore contains the sporoplasm involved in transovarial transmission. A 2nd sporulation sequence, primarily in adipose tissue, may involve both males and females. In this sequence, repeated merogonic division greatly increased the density of diplokaryotic meronts and generally involved most of the body of the host. Production of meiospores, unlike that for the binucleate spore, appeared to be spontaneous (i.e. no obligatory blood meal). Survivorship of male and female larval mosquitoes was nearly equal. Adult females spread the parasite in three ways: transovarial, transovum, and by meiospore depos

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05873.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTA rare phenomenon can occur in ciliated protists of the genusEuplotes, which can undergo genetic recombination by the normal outbreeding process of conjugation following mild starvation. Occasionally, the dominant mutation for the autogamy trait arises. Individuals possessing the trait show obligate self‐fertilization upon mild starvation. This yields, after normal asexual division, a population of individuals that are reproductively isolated from the parental outbreeding strain. A morphometric analysis of sympatric autogamous and non‐autogamous populations ofEuplotes vannusfrom Somalia demonstrates that there has been morphological drift in gross body proportions in the autogamous populations. However, the positional patterns of the locomotory organelles on the ventral surface remain unchanged. The changes in body proportions in the autogamous populations are relevant to the mechanics of the conjugation process, which involves fusion of the oral regions of paired cells belonging to complementary mating ty

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05874.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTSodium dodecyl sulfate polyacrylamide gel electrophoresis, immunoblotting, lectin binding, and125I surface labeling of sporozoites were used to probe sporozoites of the rat coccidian,Eimeria nieschulzi. Analysis of silver stained gels revealed>50 bands. Surface iodination revealed about 14 well labeled, and about 10 weakly labeled but potential, surface proteins. The most heavily labeled surface proteins had molecular masses of 60, 53–54, 45, 28, 23–24, 17, 15, 14, 13, and 12 kD. Following electrophoresis and Western blotting, 2 of the 12125I labeled lectin probes bound to two bands on the blots, which collectively indicated that two bands were glycosylated. Concanavalin A (ConA) specifically recognized a band at 53 kD, which may represent a surface glycoprotein, and a lectin derived from Osage orange (MPA) bound to a single band at 82–88 kD, that may also be a surface molecule. Immunoblotting using sera collected from rats inoculated orally with oocysts, as well as sera from mice hyperimmunized with sporozoites, revealed that many surface molecules appear to be immuno

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05875.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTA new species of microsporidium,Nolleria pulicis, is described and named here from the cat flea,Ctenocephalides felis. The genusNolleriais created and placed within the family Chytridiopsidae. The family is slightly modified to accommodate certain features of intracellular development seen inN. pulicis, which is otherwise very similar to other species in the family Chytridiopsidae. Sporulation is described from ultrastructural analysis of infected midgut epithelial cells of adultC. felis. The term “multiple division by vacuolation” is proposed for describing sporogony as it occurs in this species and certain related species of microsporidia. The probable mode of transmission and apparent absence of merogony are discus

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05876.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTMorphogenesis of cell division was investigated inUronychia transfugautilizing both light microscopy of living and stained specimens and SEM of preserved specimens. The cortical morphogenetic pattern ofUronychiais similar in several respects to that of the members of the family Euplotidae. These features include: the de novo development of the opisthe oral primordium in a subcortical pouch; the development of frontoventral and transverse cirri for both the proter and opisthe from 5 cirral primordia that form de novo within a single latitudinal developmental zone; and the absence of right marginal cirri. The members of the genusUronychiaalso show a number of unique characteristics: development of a proter oral primordium that causes partial replacement of the parental adoral zone of oral polykinetids during development of the proter; a large oral membrane that is divided into a right and left component; large caudal cirri that bend to the left; and dorsal kineties comprised of closely set paired‐kinetosome kinetids. When compared to the other euplotid‐like ciliates, these unique features support the placement of the genusUronychiain a separate family, Uronychii

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05877.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTSphaerospores were found in the kidneys of alevin channel catfish (Ictalurus punctatus) from a farm in Central California. MulticelluUr developmental stages, similar to C‐blood protozoans described forSphaerosporaspp. from cyprinid fishes, were observed in circulating blood and numerous tissues. Upon a 2nd examination of the same population offish 10 days later, sporogonic stages were seen developing into mature Sphaerospores in the lumina of the kidney tubules. Sporogeoesis was asynchronous with simple unicellular stages adjacent to more complex forms with developing polar capsules and valves. Only one elliptical spore (5.6 μm in width, 6.5 μm in thickness by 5.8 μm in length) developed within the surrounding pscudoplasmodium. Thin valves surrounded two sporoplasm cells and two subspherical polar capsules (1.7 × 1.9 μm) which contained a polar filament with four to five turns. The blood stages of theSphaerosporasp. described here are similar to the trophozoites seen in channel catfish with proliferativc gill disease (PGD). Early stages of PGD also observed in the same population of channel catfish containing developmental and sporogonic stages of this newly recognizedSphaerosporasp. may suggest a causal relationship between this new myxosporean and the gill d

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05878.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTThe continuous culturing ofTrypanosoma acomysin the presence of a murine areolar‐adipose cell line (A9) was possible for the 1st time. The trypanosomes were cultured at 37° C with A9 in DMEM supplemented with 20% heat inactivated fetal bovine serum, using an initial inoculum from primary cultures of lung or blood clots from infected spiny mice. The cultures were maintained for 115 days and underwent 15 passages before termination and cryopreservation. Using this culture systemT. acomyssubcultures were initiated from 3 different initial inocula (3 × 104, 1.5 × 105and 7.4 × 105parasites/ml) and growth curves revealed that the lowest inoculum gave the best growth pattern. This inoculum yielded a population doubling time of less than 12 h for 4 days, a high peak density of 7 × 106parasites/ml and the most gradual decline compared to the other 2 inocula. Rosetting epimastigotes and nests of amastigotes were observed in close association with the feeder layer cells. Epimastigotes were the most predominant form in culture supernatants but other morphological forms observed included trypomastigotes and sphaeromast

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05879.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTChromatin spreads made from isolated nuclei of the unicellular green algaChlamydomonas reinhardtiishow the beaded fibers typical of eukaryotic polynucleosomes. Micrococcal nuclease digestions confirmed the presence of nucleosomes with a repeat length of 189 base pairs, essentially the same as typical mammalian cells. Basic nuclear proteins extracted from isolated nuclei or chromatin with 1 M calcium chloride and 0.3 M hydrochloric acid are resolved into seven major components by electrophoresis in the presence of sodium dodecyl sulfate (SDS). These seven components were subjected to qualitative peptide mapping with V8 protease on SDS gels for comparison with the major histone components of calf thymus. Finally, theC. reinhardtiibasic nuclear proteins were fractionated by reversed phase high performance liquid chromatography and their amino acid composition determined. From these studies, we conclude thatC. reinhardtiihas a full complement of the five histones with properties very similar to those of both higher animals and higher plants.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05880.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

ABSTRACTTo identify the surface features ofHolospora obtusaduring its differentiation from the reproductive short form to the infectious long form, bacteria of four different buoyant densities were isolated by Percoll density gradient centrifugation of homogenates of host cells or isolated macronuclei, and examined with a scanning electron microscope. Bacteria of buoyant density 1.09 g/ml were reproductive short forms as well as cells at various stages in the elongation process including fully elongated ones. Bacteria of buoyant densities 1.11 g/ml and 1.13 g/ml were premature long forms and those of 1.16 g/ml were mature infectious long forms. Bacteria of buoyant density 1.09 g/ml had an entirely rough surface while those of buoyant densities 1.11 g/ml and 1.13 g/ml were smooth and had wale‐like stripes on their surface. A small tapered tip was observed at one end of the bacteria of buoyant density 1.13 g/ml. Bacteria of buoyant density 1.16 g/ml had an entirely smooth surface, but one end always showed a rough surface; this locally differentiated surface of the special tip of the infectious long form may be responsible for both the nuclear and species specificities of the infectivity ofH. obtusa. These observations indicate that the surface ofH. obtusachanges during differentiation and the special tip develops in bacteria of buoyant density 1.13 g/m

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1990.tb05881.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY