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1.
Twelve aborted foetuses (gestational ranged from 4–9 months) and dams from dairies cattle farms in (Mashhad) Iran were analysed to investigate the participation of Neospora caninum in abortion. Diagnosis of the infection was determined by histopathology, serology (indirect fluorescent antibody test [IFAT]) and semi-nested polymerase chain reaction (PCR). A total 33% of bovine foetuses were considered to be infected by PCR technique. Microscopic lesions consistent with N. caninum infection in foetal brains were observed in 25% of the samples, whereas 33% were positive using IFAT (with a cut-off titre of 1:20). This study confirms the importance of N. caninum as an important cause of abortion in Iran.  相似文献   

2.
The occurrence of antibodies to Neospora caninum and Toxoplasma gondii was determined in 400 domestic cats (Siamese, Persian, and undetermined breeds) from the Municipality of Araçatuba, Sao Paulo, Brazil, through the indirect fluorescence antibody test (IFAT). Of the 400 cats, 100 were seropositive to T. gondii (25%, titer ≥64) and 98 to N. caninum (24.5%, titer ≥16). The rate of seropositive cats for T. gondii was correlated with age (χ 2=35.7; p<0.001), with a higher number of infected animals at older ages. Of the 219 cats younger than 1-year-old, 13.2% were seropositive for T. gondii, while 39.2% were positive in the 181 older animals. The presence of N. caninum was also correlated with age (÷2=8.8; p<0.01), with 18.7% (41/219) and 31.5% (57/181) of positive animals at ages below and above 12-month, respectively. An association between the occurrences of both protozoa in the felines was also observed (χ 2=19.6; p<0.001).  相似文献   

3.
A seroprevalence survey of Neospora caninum and bovine herpesvirus 1 (BHV-1) was conducted in cattle pasturing in an area of the southern Italian Apennines to investigate the coinfection of these two pathogens. Blood samples were collected from 948 pastured cattle raised on 81 farms. Sera were tested for antibodies to N. caninum and to BHV-1 using an ELISA assay and a neutralization test, respectively. Out of the 81 farms sampled, 63 (77.8%) were positive for N. caninum and 80 (98.8%) for BHV-1. Coinfection was found in 62 (76.5%) farms. Out of the 948 bovine sera samples, 303 (32.0%) had antibodies to N. caninum and 735 (77.5%) to BHV-1. The copresence of antibodies to N. caninum and BHV-1 was found in 256 (27.0%) cattle. The logistic regression results indicated that seropositivity for BHV-1 was a risk factor for N. caninum seropositivity and seropositivity for N. caninum was a risk factor for BHV-1 seropositivity.  相似文献   

4.
103 serum samples were taken from owned dogs in Tehran (53 urban dogs and 50 farm dogs) from February to May 2005 and tested for IgG antibody against Neospora caninum using the immunofluorescence antibody test. Urban dogs were selected from apparent healthy dogs referred to the Small Animal Hospital of Faculty of Veterinary Medicine, University of Tehran, for routine operation, and the farm dogs were selected from the sheepdogs in sheep flocks around Tehran randomly. The titer of 1:50 was selected as cutoff. In total, 20 of 103 cases (19.4%) were identified as positive. The infection rate in farm dogs (28%) was higher than in urban dogs (11.3%), and the difference was statistically significant (p < 0.05). The infection rates in different genders and age groups were determined. The differences between seroprevalence of N. caninum infection in different sexes were not significant. A high correlation was observed between the infection rate and age (r 2 = 0.97, p < 0.01).  相似文献   

5.
Mice infected with tachyzoites of Neospora caninum (syn.: Hammondia heydorni) must be pretreated with cortisone in order to show disease symptoms. This indicates the status of an opportunistic agent of disease. Toltrazuril was an effective curative agent.  相似文献   

6.
Limited data is available on the vertical transmission of Neospora caninum via the colostrum. The results of our previous research revealed the presence of N. caninum DNA in the milk of seropositive cows. The aim of the present work is to demonstrate parasite DNA in colostrum samples. A polymerase chain reaction using Np21 and Np6 primers was applied to DNA isolated from the colostrum sediment in order to amplify the corresponding genomic Nc-5 region. The expected 328-bp product was obtained in colostrum samples collected both on the calving day and the day after. This is the first detection of N. caninum DNA in the colostrum of seropositive cows, and these findings implicate the possibility of N. caninum transmission through the colostrum.  相似文献   

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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.
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   

10.
In Europe, Serbia ranks among countries with a high prevalence of Trichinella infection in pigs, which continues to be a serious human health problem. While in some Balkan countries, more than one Trichinella species/genotype has been described in both the sylvatic and domestic cycles, these data are lacking for Serbia. To date, only a few Serbian isolates of Trichinella have been genetically specified, and all were classified as T. spiralis. Although transmission of Trichinella from domestic pigs to wildlife could be assumed, neither the infection status nor the species of Trichinella circulating among wildlife in Serbia has been investigated. This study shows the presence of two Trichinella species, T. spiralis and T. britovi, in wild animals originating from five districts in Serbia, where Trichinella infections in domestic pigs and humans have been recorded. Trichinella spiralis was detected in jackals (n = 3), red foxes (n = 2) and a wild cat (n = 1). We also established that wolves (n = 4) and red foxes (n = 2) serve as sylvatic reservoirs for T. britovi. This is the first report on the presence of T. britovi in Serbia.  相似文献   

11.
Neospora caninum is a tissue cyst-forming coccidium that may cause neuromuscular disorders in dogs. Infected bitches can transmit the parasite to their pups in utero. Vertical transmission may occur after primary infection during pregnancy and in subsequent pregnancies. The reason why only a few pups develop clinical neosporosis is unknown. We obtained sera from a Doberman bitch and its offspring delivered in three litters. The bitch had a titer of 1:640 in an indirect fluorescent antibody test (IFAT). At least three pups of litter A, one pup of litter B, and two pups of litter C were also seropositive for N. caninum. However, clinical neosporosis developed only in one pup of litter C, which had the highest IFAT titer (1:5,120) of all dogs examined. Western blots carried out after one-dimensional and two-dimensional separation of N. caninum tachyzoites revealed that the largest number of antigens was recognized by sera derived from the bitch. The lowest number of antigens was recognized by serum from the pup with clinical neosporosis. However, this pup uniquely recognized a major antigen with a molecular weight of about 17,000. The information collected in this study adds to our knowledge on why some pups develop clinical neosporosis and others do not.  相似文献   

12.
Obeliscoides cuniculi is a New World nematode parasite of the Trichostrongilidae family infecting the gastric tract of different domestic and wild Lagomorph species. This parasite is reported for the first time from a European brown hare (Lepus europaeus). The nematodes isolated from the gastro-intestinal tract were identified using the primary characteristics used to differentiate the species of this genus as adults morphology (length and thickness) and other characteristics of spicules, cervical papillae, cuticular ridges and striations. In the Italian study area, the European brown hare lives in sympatry with the eastern cottontail (Sylvilagus floridanus), species in which the nematode was previously isolated; therefore, the possibility of a cross-infestation must be considered.  相似文献   

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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   

16.
The tick-borne diseases of livestock constitute a complex of several diseases with different etiological agents, such as protozoa, rickettsia, bacteria, and viruses. One problem discussed in protozoan infection is the determination and characterization of the transmitter agent. Because many analyses were performed with the salivary gland smears using the methyl-green-pyronin staining method or the Feulgen staining method, the transfer vector remains unanswered in some cases. The aim of this study is to recognize Babesia ovis in the salivary gland of Rhipicephalus spp. using polymerase chain reaction (PCR). Deoxyribonucleic acid (DNA) was isolated from 269 salivary gland of Rhipicephalus spp. (108 R. bursa, 87 R. turanicus, 74 R. sanguineus) collected from sheep with suspected to babesiosis. The isolated DNA was then analyzed with the primers derived from the hypervariable region V4 of 18S ribosomal ribonucleic acid (rRNA) of the Babesia species. For the specificity of the PCR product and discriminating from Babesia motasi and Babesia crassa, nested PCR and restriction fragment length polymorphism was performed. As positive control for the DNA extraction procedure, the DNA was analyzed with the common primers designed from the 18S rRNA of the Ticks (Rhipicephalus, Hyalomma, Haemophysalis, Dermacentor, Ixodes, Boophilus). B. ovis was detected in salivary gland of 18.5% R. bursa, 9.1% R .turanicus, and 8.1% R. sanguineus, respectively.  相似文献   

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18.
Repeat induced point mutation (RIP) is a gene silencing mechanism present in fungal genomes. During RIP, duplicated sequences are efficiently and irreversibly mutated by transitions from C:G to T:A. For the first time, we have identified traces of RIP in transposable elements of Aspergillus niger and Penicillium chrysogenum, two biotechnologically relevant fungi. We found that RIP in P. chrysogenum has affected a large set of sequences, which also contain other mutations. On the other hand, RIP in A. niger is limited to only few sequences, but literally all mutations are RIP-like. Surprisingly, RIP occurred only in transposon sequences that have disrupted open reading frames in A. niger, a phenomenon not yet reported for other fungi. In both fungal species, we identified two sequences with strong sequence similarity to Neurospora crassa RID. RID is a putative DNA methyltransferase and the only known enzyme involved in the RIP process. Our findings suggest that both A. niger and P. chrysogenum either had a sexual past or have a sexual potential. These findings have important implications for future strain development of these fungi.  相似文献   

19.

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   

20.
Pseudomonas aeruginosa is an opportunistic pathogen of immunocompromised hosts. In cystic fibrosis (CF), P. aeruginosa causes acute and chronic lung infections that result in significant morbidity and mortality. P. aeruginosa possesses several traits that contribute to its ability to colonize and persist in acute and chronic infections. These include high resistance to antimicrobials, ability to form biofilms, plethora of virulence products, and metabolic versatility. In P. aeruginosa, a cell-to-cell communication process termed quorum sensing (QS) regulates many of these factors that contribute to its pathogenesis. Recent evidence suggests that the CF lung environment presents a specialized niche for P. aeruginosa. The relationship of P. aeruginosa QS, biofilm formation, and the CF lung environment is discussed.  相似文献   

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