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A total of 206 Virginia opossums (Didelphis virginiana) collected from the mid-Michigan region, United States, during a period extending from 1996 to 2002 were sampled for the presence of Sarcocystis spp sporocysts. All isolates were phenotypically identified as Sarcocystis spp and genotyped to the species level by PCR-based techniques. The overall prevalence of Sarcocystis spp in opossums was 18% (37/206). The prevalence of Sarcocystis spp differed significantly with age (P<0.001) and adult opossums were more commonly infected (14.6%; 30/206) than juveniles (3.4%; 7/206). No significant difference in the prevalence of Sarcocystis spp infection was observed between male and female (P<0.15). The highest prevalence was recorded during summer (9.2%; 19/206). PCR-RFLP analyses demonstrated the majority of Sarcocystis isolates to be S. neurona, with some animals co-infected with sporocysts of S. falcatula. Out of the 37 Sarcocystis-infected opossums, 23 (62%) had sporocysts of S. neurona only, four (11%) had sporocysts of S. falcatula only, and eight (22%) had a mixture of S. neurona and S. falcatula sporocysts. These findings indicate that mixed Sarcocystis infections in opossums are common. The propensity for Sarcocystis spp to co-exist in the opossum gut enhances dissemination and environmental contamination with these coccidia. Additionally, this increases the chance for sexual recombination between Sarcocystis spp, given the proclivity of these species to reproduce sexually at high numbers in the intestinal cells of their definitive host. 相似文献
3.
All trypanosome species classified in the subgenus Herpetosoma in sciurid hosts have been recorded from ground and tree squirrels to date, but not from any flying squirrels. We describe in this paper a novel trypanosome species, Trypanosoma (Herpetosoma) kuseli sp. n., from Siberian flying squirrels (Pteromys volans) imported from China, and compare it with T. (H.) otospermophili in Richardson's ground squirrels (Spermophilus richardsonii) and Columbian ground squirrels (Spermophilus columbianus) from the USA. Due to a short free flagellum, the new species appeared stumpy compared with T. otospermophili (length of free flagellum 7.0 +/- 0.8 microm, total length 32.1 +/- 0.8 microm, n = 13 and length of free flagellum 15.5 +/- 1.6 microm, total length 35.9 +/- 1.0 microm, n = 13, respectively). Another conspicuous morphological feature of the new species was an anteriorly positioned kinetoplast, found approximately at the midpoint between the nucleus and the posterior end. These characters have not been recorded from any squirrel Herpetosoma trypanosome species. Comparison of the nucleotide sequences of the small and large subunit rRNA genes indicated that T. kuseli sp. n. was more homologous to T. otospermophili than murid Herpetosoma species, such as T. grosi, T. lewisi, T. musculi, T. microti and T. evotomys. 相似文献
4.
María del Rosario Robles James E. Loudon John M. Kinsella Mandala Hunter-Ishikawa David S. Miller Michelle L. Sauther Frank P. Cuozzo 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2010,55(3):270-275
Lemuricola (Madoxyuris) bauchoti Chabaud, Brygoo et Petter, 1965 is redescribed from material collected from the ring-tailed lemur, Lemur catta, from the Beza Mahafaly Special Reserve in Madagascar using the scanning electron microscope. This is a new host record and
the first oxyurid reported from the ring-tailed lemur. Previously, records of each species of the subgenus Madoxyuris have been restricted to a single host species, but the close relationship between these nematodes and their Strepsirrhini
hosts will only be proven when additional records fill in the gaps in their distribution. 相似文献
5.
Karina?M.?Rebello Luzia?M.?C.?C?rtes Bernardo?A.?S.?Pereira Bernardo?M.?O.?Pascarelli Suzana?C?rte-Real Léa?C.?Finkelstein Rosa?T.?Pinho Claudia?M.?d’Avila-Levy Carlos?R.?Alves 《Parasitology research》2009,106(1):95-104
Leishmania (Viannia) braziliensis is the major causative agent of American tegumentary leishmaniasis, a disease that has a wide geographical distribution and
is a severe public health problem. The cysteine proteinase B (CPB) from Leishmania spp. represents an important virulence factor. In this study, we characterized and localized cysteine proteinases in L. (V.) braziliensis promastigotes. By a combination of triton X-114 extraction, concanavalin A-affinity, and ion exchange chromatographies, we
obtained an enriched fraction of hydrophobic proteins rich in mannose residues. This fraction contained two proteinases of
63 and 43 kDa, which were recognized by a CPB antiserum, and were partially sensitive to E-64 in enzymatic assays with the
peptide Glu-Phe-Leu. In confocal microscopy, the CPB homologues localized in the peripheral region of the parasite. This data
together with direct agglutination and flow cytometry assays suggest a surface localization of the CPB homologues. The incubation
of intact promastigotes with phospholipase C reduced the number of CPB-positive cells, while anti-cross-reacting determinant
and anti-CPB antisera recognized two polypeptides (63 and 43 kDa) derived from phospholipase C treatment, suggesting that
some CPB isoforms may be glycosylphosphatidylinositol-anchored. Collectively, our results suggest the presence of CPB homologues
in L. braziliensis surface and highlight the need for further studies on L. braziliensis cysteine proteinases, which require enrichment methods for enzymatic detection. 相似文献
6.
Experimental infections of Galba truncatula with Paramphistomum daubneyi were carried out to determine at day 50 (at 24 degrees C) the numbers of sporocysts, which grew in infected snails via the count of first- and second-generation rediae. In snails individually exposed to one, two, three, four, or five miracidia, the numbers of first-generation rediae increased from the one-miracidium group to the five-miracidium snails (from a mean of 6.7 to 26.1), while second-generation rediae decreased in number (from 6.2 to 0.9, respectively). This scale of redial numbers was used to determine the number of sporocysts, which grew in naturally infected snails collected from sedimentary or acid soils between 1993 and 2006. In cercariae-containing snails, natural infections resulting from the development of one to five sporocysts were found in both samples of G. truncatula examined. The numbers of 3-, 4-, and 5-sporocyst infections were increasing over time since 1997, 2000, and 2003, respectively. The utility of such multiple-sporocyst infections is open to question, as the differentiation of second-generation rediae and that of procercariae were delayed and always limited. They might be interpreted as a consequence of a zoonosis, which has been spreading since 1990 in ruminants of central France. 相似文献
7.
Coppin JF Lefebvre C Caby S Cocquerelle C Vicogne J Coustau C Dissous C 《Parasitology research》2003,89(2):113-119
8.
Galba truncatula snails were experimentally infected with either of two different isolates of Fasciola gigantica, originating from Egypt or China, to determine the influence of these isolates on the characteristics of snail infections. The survival rates of G. truncatula on day 30 post-exposure were 90.0% and 60.2% in the Egyptian and Chinese groups, respectively. The frequency of cercaria-shedding snails within the Egyptian group was 79.8%, whereas in the Chinese group it was 22.4%. The parasite origin had a significant effect on the durations of the prepatent and patent periods. The mean number of cercariae shed from the Egyptian group was significantly greater than that shed from the Chinese group (a mean of 275.5 per cercaria-shedding snail compared with 29.0). These results could be explained by the fact that G. truncatula might be a natural intermediate host for F. gigantica in Egypt, and the greater adaptability of the Egyptian miracidia of F. gigantica to unusual snail hosts. These results demonstrate the influence of the geographic origin of the parasite on the success of trematodes infecting snails. 相似文献
9.
Weihuan Huang Xiaoli Zhang Yifei Wang Wencai Ye Vincent EC Ooi Hau Yin Chung Yaolan Li 《Chinese medicine》2010,5(1):23
Background
Radix Wikstroemiae is a common Chinese herbal medicine. The ethyl acetate fraction of the ethanolic extract of W. indica possesses potent in vitro antiviral activity against respiratory syncytial virus (RSV). This study aims to identify the antiviral components of the active fraction. 相似文献10.
Suckling rabbits from six litters were orally inoculated at various ages with oocysts of Eimeria flavescens or Eimeria intestinalis. The total number of oocysts in the ceca served to estimate parasite reproduction. The rabbits at 14 and 16 days old remained
uninfected, and in 19-day-old animals, low or no oocyst shedding was observed. All the older rabbits were infected and the
number of oocysts in the ceca increased with the age of animals at inoculation. The dependence of oocyst production on the
age of inoculated rabbits was similar in both coccidian species. 相似文献
11.
Macroderoides texanus n. sp. is described based on 16 specimens collected from the intestine of the North American alligator gar, Atractosteus spatula. Of the five established species of Macroderoides, the new species is morphologically most similar to Macroderoides spiniferus and Macroderoides trilobatus. M. texanus n. sp. differs from M. spiniferus by having the ovary situated immediately posterior to the cirrus sac rather than at mid-way between the cirrus sac and anterior
testis, the ventral sucker situated further posteriorly, and the vitelline fields extending somewhat posterior to posterior
testis rather than to the middle of posterior testis. M. texanus n. sp. differs from M. trilobatus by having the ovary positioned immediately adjacent to, or overlapping the cirrus sac rather than at some distance posterior
to it, and by having significantly larger eggs. Additionally, the new species has two distinctive rows of spines on the postero-ventral
surface of the oral sucker that are lacking in M. spiniferus and M. trilobatus. Comparison of approximately 2,700-base-pair sequences of nuclear rDNA (partial 18S, complete ITS region and partial 28S)
from M. texanus n. sp., M. spiniferus and M. trilobatus, strongly supports the status of M. texanus n. sp. as a new species. 相似文献
12.
Occurrence of <Emphasis Type="Italic">Cryptosporidium hominis</Emphasis> in pigeons (<Emphasis Type="Italic">Columba livia</Emphasis>) 总被引:1,自引:0,他引:1
Néstor Abreu-Acosta Pilar Foronda-Rodríguez Mercedes López Basilio Valladares 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2009,54(1):1-5
This study demonstrated the presence of Cryptosporidium hominis in pigeons for the first time. Previously, C. hominis had been cited only in another bird species, Branta canadiensis. The present findings suggest that pigeons may act as mechanical vectors for this protozoan. 相似文献
13.
Zlatka M. Dimitrova 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2009,54(1):53-56
In total, 2097 individuals of Trachelipus squamuliger and 20 individuals of Armadillidium vulgare from four habitats (three woodland sites and one pasture) in the region of Stara Zagora, Bulgaria, were examined for the
presence of cystacanths of Plagiorhynchus cylindraceus, a common acanthocephalan parasite of passerine birds. In T. squamuliger from woodland habitats, cystacanths were found with prevalence 4.0–9.3%, intensity 1–5 (mean 1.22–1.57) and mean abundance
0.057–0.113. No significant differences were observed between infections in males and females of T. squamuliger. None of the T. squamuliger individuals from the pasture examined was infected. Out of 48 infected females of T. squamuliger, only one had developed eggs (in agreement with previous studies revealing the negative effect of the cystacanths on the
development of female gonads of woodlice). One individual of A. vulgare was infected with a single cystacanth. The occurrence of P. cylindraceus in T. squamuliger is a new host record. 相似文献
14.
A 14-year-old boy who was neutropenic following chemotherapy for leukemia developed fungemia caused by the yeast Kodomaea ohmeri (Pichia ohmeri). The infection was cured by catheter removal and the use of fluconazole. A 74-year-old man who had undergone surgeries for a subcutaneous tumor developed polymicrobic cellulitis involving Kodomaea ohmeri. Despite surgical debridement and antibiotic therapy, the patient died of complications. Including these 2 cases, there have been 10 Kodomaea ohmeri infections reported thus far, all occurring in patients with pre-existing conditions. There have been seven cases of fungemia and one case each of peritonitis, funguria, and cellulitis. The treatment employed varied depending on the site/source of infection. Seven patients recovered and three died. The microbiological data available suggest that Kodomaea ohmeri can be identified definitively by biochemical tests and is susceptible to amphotericin B and either susceptible to or dose dependently susceptible to itraconazole and fluconazole. 相似文献
15.
Silva-Lopez RE Morgado-Díaz JA Alves CR Côrte-Real S Giovanni-De-Simone S 《Parasitology research》2004,93(4):328-331
Extracellular proteolytic activity was detected in a Leishmania (L.) amazonensis culture supernatant and a 56-kDa protein was purified using (NH4)2SO4 precipitation followed by affinity chromatography on aprotinin–agarose. A rabbit serum obtained against the 56-kDa extracellular serine protease was used in order to analyze its location in L. (L.) amazonensis parasites. Immunocytochemistry studies revealed that the enzyme is mainly found in the flagellar pocket and cytoplasmic vesicles of promastigote forms, whereas in amastigotes, it is located in electron-dense structures resembling megasomes. These results indicate that the 56-kDa serine protease is released into the extracellular environment through the flagellar pocket; and its intracellular location suggests either a correlated enzymatic activity or intracellular trafficking. 相似文献
16.
Passero LF Carvalho AK Bordon ML Bonfim-Melo A Toyama MH Corbett CE Laurenti MD 《Inflammation research》2012,61(3):255-263
Objective
Leishmania (Viannia) shawi was characterized only recently, and few studies concerning the immunogenic and protective properties of its antigens have been performed. The present study aimed to evaluate the protective potential of the five antigenic fractions isolated from L. (V.) shawi promastigotes in experimental cutaneous leishmaniasis. 相似文献17.
Bardia A Tiwari SK Gunisetty S Anjum F Nallari P Habeeb MA Khan AA 《Inflammation research》2012,61(4):359-365
Objective
The present study was designed to investigate the role of X-ray cross-complementing group 1 (XRCC1) and apurinic/apyrimidinic endonuclease 1 (APE1) polymorphisms in apoptosis and the risk of ulcerative colitis (UC). 相似文献18.
Mansour MF 《Parasitology research》2012,110(4):1357-1362
The present study describes, for the first time, the sperm ultrastructure of the parasite Acanthostomum spiniceps (Digenea: Acanthostomidae). The adult worms of this species were collected from the freshwater fishes, Bagrus bayad and Bagrus docmac, caught from the Damietta branch of the River Nile in Dakahlia Governorate, Egypt. Ultrastructure of the sperm of this species
revealed that it can be differentiated into seven regions. It is characterized by its filiform shape, tapers anterior, and
posterior ends; the two axonemes are in close contact with the plasma membrane and the presence of two mitochondria as one
anterior and the other is posterior. The two mitochondria are parallel at a short distance enclosing the first part of nucleus
in between. The nucleus is characteristically formed of unusual network of chromatin which is vacuolated. The spermatozoon
of A. spiniceps is similar to that of most parasitic Platyhelminthes. 相似文献
19.
de Souza Chagas AC de Barros LD Cotinguiba F Furlan M Giglioti R de Sena Oliveira MC Bizzo HR 《Parasitology research》2012,110(1):295-303
Herbal drugs have been widely evaluated as an alternative method of parasite control, aiming to slow development of resistance
and obtain low-cost biodegradable parasiticides. This study evaluated the in vitro efficacy on Rhipicephalus (Boophilus) microplus of extracts from Carapa guianensis seed oil, Cymbopogon martinii and Cymbopogon schoenanthus leaf essential oil, and Piper tuberculatum leaf crude extract and similar synthesized substances. In the immersion test, engorged females were evaluated in five dilutions
ranging from 10% to 0.030625% concentration. In the larval test on impregnated filter paper, the concentration ranged from
10% to 0.02%. The treatments and controls were done in three replicates. Chemical analysis of the oils was performed by gas
chromatography. The main compounds were oleic acid (46.8%) for C. guianensis and geraniol for C. martinii (81.4%), and C. schoenanthus (62.5%). The isolated and synthesized substances showed no significant effect on larvae and adult. C. martinii and P. tuberculatum showed the best efficacy on the engorged females. The LC50 and LC90 were 2.93% and 6.66% and 3.76% and 25.03%, respectively. In the larval test, the LC50 and LC90 obtained for C. martinii, P. tuberculatum, and C. schoenanthus were 0.47% and 0.63%, 0.41% and 0.79%, 0.57% and 0.96%, respectively. The fact that geraniol is present in greater quantities
in C. martinii explains its higher activity in relation to C. shoenanthus. It is necessary to validate the in vivo use of safe and effective phytoparasiticidal substances. Efforts should be focused
on developing formulations that enhance the efficacy in vivo and lengthen the residual period. 相似文献
20.
M. Friedemann 《European journal of clinical microbiology & infectious diseases》2009,28(11):1297-1304
About 120–150 neonatal Cronobacter spp. (Enterobacter sakazakii) infections have been described. An analysis of current case numbers, epidemiological measures and risk factors is warranted.
Data of microbiologically confirmed cases, published between 2000 and 2008, have been analysed statistically. More than 100
neonatal Cronobacter infections have been reported in this period. The overall lethality of the 67 invasive infections was 26.9%. The lethality
of Cronobacter meningitis, bacteraemia and necrotising enterocolitis (NEC) was calculated to be 41.9% (P < 0.0001), <10% and 19.0% (P < 0.05), respectively. Logistic regression models (P < 0.0001) revealed a higher gestational age at birth and parentage not from Europe as significant factors for a higher reporting
probability of neonatal Cronobacter meningitis. Neonates with Cronobacter meningitis not originating from North America have a higher risk for lethal outcome than other neonatal Cronobacter infections (P < 0.0001). Continental differences of risk factors for Cronobacter meningitis and for the lethal outcome of neonatal meningitis should be elucidated. Neonatal Cronobacter infections are mainly associated with the contamination of infant formula and of the relevant cleaning and preparation equipment.
Eleven neonatal Cronobacter infections, not caused by contaminated infant formula, have been retrieved. Other environmental sources of infection should
be considered. Consistent and sufficiently informative data of invasive neonatal Cronobacter infections should be recorded in a centralized reporting system. 相似文献