摘要:

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

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03167.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTLagenophrys singularisis removed fromLagenophrysand designated the type species ofParalagenophrysn. g. Compared to members ofLagenophrys, the oral area ofP. singularisis radically distorted.Paralagenophrysapparently also lacks second‐type division, a special phase of sexual reproduction characteristic ofLagenophrysand associated with its adaptation to symbiotic life on crustaceans. Members ofLagenophrysare obligate ectocommensals of crustaceans. In contrast,P. singularis(Kellicott, 1887) n. comb. occurs most often on the leaves of aquatic vascular plant

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03168.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTCellulose acetate electrophoresis (CAE) was used to separate glucosephosphate isomerase, hexokinase, malic enzyme, and phosphoglucomutase extracted from invasive and non‐invasiveEntamoeba histolyticaand “E. histolytica‐like” organisms. Each of these morphologically similar organisms possessed a unique CAE isoenzyme profile that can be used as an aid in their identification. The CAE technique used to obtain these isoenzyme profiles is rapid, simple, and economical, and it requires neither specialized training nor claborate eq

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03169.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTFirst‐generation development ofEimeria tuskegeensiswas evaluated using light microscopy. Sporozoite‐shaped meronts containing a prominent refractile body were observed in small intestinal cells of an experimentally infected cotton rat at 24 h post inoculation (PI). Mature spherical or subspherical meronts containing crescent‐shaped merozoites were observed at 36 h PI. Refractile bodies were observed in some of these merozoites. Sporozoite‐shaped meronts that were isolated from host intestinal cells and inoculated onto human fetal lung cell cultures penetrated the cultured cells by 2 h PI. A mature, subspherical, first‐generation meront containing seven merozoites was observed at 9 h PI in cell culture, indicating that sporozoite‐shaped meronts isolated from the host retained their

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03170.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTA leptomonad flagellate found in the macronucleus of the hypotrichous ciliateParaholosticha sterkiicarries out its whole life cycle there. The ciliates can divide, encyst, and excyst even when parasitized, and the flagellates are maintained throughout. Parasite‐free ciliates may be rapidly infected. The light‐ and electron‐microscopic structure of the flagellate resembles that of other leptom

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03171.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTProliferation ofAcanthamoeba castellanii(Neff strain) in either a broth medium or a defined medium was arrested by α‐monofluoromethyldehydroornithine (Δ‐MFMOme), α‐difluoromethylornithine (DFMO), and (R, R')‐δ‐methyl‐α‐acetylenic putrescine (MAP), three specific inhibitors of ornithine decarboxylase. Although all three inhibited the ameba enzyme, Δ‐MFMOme was the most effective inhibitor of multiplication. Growth inhibition was reversed by the addition of polyamines. The inhibitors did not induce differentiation by themselves although DFMO caused encystment when supplement

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03172.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTThis report describes the fine structure of the erythrocytic stages ofPlasmodium malariae. Erythrocytic parasites from a naturally acquired human infection and an experimentally infected chimpanzee were morphologically indistinguishable and structurally similar to other primate malarias. New findings included observations of highly structured arrays of merozoite surface coat proteins in the cytoplasm of early schizonts and on the surface of budding merozoites and the presence of knobs in the membranes of Maurer's clefts. Morphological evidence is presented suggesting that proteins are transported between the erythrocyte surface and intracellular parasites via two routes: one associated with Maurer's clefts for transport of membrane‐associated knob material and a second associated with caveolae in the host cell membrane for the import or export of host‐ or parasite‐derived substances through the erythrocyte cyto

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03173.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTAn intranuclear microsporidium is described from hemoblastic cells of the chinook salmon,Oncorhynchus tshawytscha. The infection is associated with an acute anemia in the fish. Up to 47% of the hemoblast nuclei were infected in anemic fish. The organisms, found only in spleen and kidney tissues, were 1–2 μm in diameter and consisted of vegetative and early sporulation forms. This microsporidium differs from known species which parasitize fish in its tissue location; however, the absence of mature spores and other life cycle stages precludes determination of its precise taxonomic identi

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03174.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTFive polyamines which could be separated by high performance liquid chromatography were found inAcanthamoeba castellanii(strain Neff). These included in order of decreasing abundance: 1,3‐diaminopropane, spermidine, spermine, norspermidine, and putrescine. Only diaminopropane and norspermidine had been found previously. Spermine was present in cultures grown in broth, but not in defined medium. Radioactive substrates were used to establish that putrescine was synthesized by decarboxylation of ornithine, ornithine was synthesized from arginine or citrulline, and diaminopropane was synthesized from spermidine. The presence of ornithine decarboxylase (EC 4.1.1.17), arginase (EC 3.5.3.1), and urease (EC 3.5.1.5) and the absence of arginine decarboxylase (EC 4.1.1.19) were established. A scheme for polyamine biosynthesis inA. castellaniiis propose

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03175.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

ABSTRACTGranules released from human eosinophils upon interaction withTrypanosoma cruziamastigotes in vitro were seen attached to the surface of non‐internalized parasites by electron microscopy. Amastigote damage was preceded by the binding of eosinophil granule material to its membrane, and eosinophil granule major basic protein (MBP) bound to the parasite surface was readily detectable. Additional evidence of eosinophil cytotoxicity for extracellular amastigotes was the observation that amastigotes trapped between two eosinophils, without being ingested by either one, were destroyed at the interface. Amastigotes isolated from the spleens of infected mice or grown in culture were similarly sensitive to the lytic effects of purified MBP. These results demonstrate the ability of human eosinophils to lyseT. cruziamastigotes extracellularly in the absence of antibody and suggest that MBP may be involved in the effect. Thus, eosinophils, known to be capable of destroying phagocytosed amastigotes, could also contribute to the clearance of these parasites through extracellular killin

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1987.tb03176.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY