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1.
The mobile genetic element PCR (MGE-PCR) is a simple and sensitive technique that can be used to detect genetic variability in Trypanosoma brucei ssp. To investigate the reliability of MGE-PCR in genotyping Trypanosoma evansi, stocks that were isolated directly from camels and after their respective passage in mice were analyzed. Construction of a dendrogram using the MGE-PCR banding profiles revealed a clear distinction between T. evansi and T. brucei, as well as discriminating the T. evansi strains (T. evansi with minicircle types B and A). A minor host-dependent clustering shows a genetic difference of <15%. Changes in the banding profiles were observed after serial passage of T. evansi type B in mice, while those of T. evansi type A were identical. It is apparent that significant random insertion mobile element positional variation occurs when T. evansi isolates are introduced into a new host, a factor that needs to be considered when MGE-PCR is used to determine genetic variation in T. evansi isolates that have different host origins.  相似文献   

2.
Whole blood samples were collected from 117 male clinically healthy Camelus dromedarius aged between 6 months to 18 years from several farms in Yazd Province of Iran. Trypanosoma evansi-affected camels were detected by Giemsa-stained blood smears, and the positive blood samples (4 out of 117) were submitted to PCR examination and phylogenetic analysis. Basic Local Alignment Search Tool data of the obtained complete internal transcribed spacer (ITS) sequences revealed that they corresponded to those of T. evansi, Thailand cattle isolate (AY912276) with the homology of 99 %. Both phylogenetic trees generated by ITS1 and complete ITS were unable to clearly show inter- and intraspecific genetic diversity of Trypanosoma spp. isolates. The phylogenetic tree inferred from the ITS2 nucleotide sequences (569 bp) clearly showed the genetic diversity of the parasites. Phylogenetic and molecular analyses of this region showed that two distinct genotypes of T. evansi in Iranian dromedary camels are present. In contrast to the ITS1 and ITS2 regions, multiple alignment of the nucleotide sequence of the 5.8S rRNA showed a high degree of sequence conservation during evolution in various Trypanosoma spp.  相似文献   

3.
The objective of the present study was to determine the prevalence and associated determinants (e.g., sex, age, on-farm management and husbandry) of gastrointestinal (GI) helminths in the domestic animals of district Toba Tek Singh, Punjab, Pakistan. For this purpose, 1,140 cattle, 1,140 buffaloes, 660 goats, 840 sheep, and 156 camels were randomly selected and their fecal samples were screened every other week for a year using a modified floatation technique. The samples positive for strongyle-type eggs had the parasite species identified using coproculture. It was found that the prevalence of GI helminths was significantly higher (P < 0.05) in sheep (44.17%; 371/840) than in other livestock. Sheep were followed in order by goats (40.15%; 265/660), buffaloes (39.82%; 454/1,140), and cattle (33.68%; 384/1,140). The important helminth species identified were Fasciola (F.) gigantica, Fasciola hepatica, Haemonchus contortus, Toxocara vitulorum, Trichostrongylus spp., Oesophagostomum spp., Ostertagia spp., Cooperia spp., Strongyloides spp., Moniezia spp., and Trichuris spp. The prevalence of GI helminths except F. hepatica and F. gigantica was significantly higher in grazing animals, females (P < 0.05) and young (P < 0.05) of all the host species when compared with stall-fed animals, males and adults, respectively. Using ponds and rivers/canals as drinking water were found to have significant influence (P < 0.05) on the prevalence of GI helminths. The results provide a baseline data for planning future research and control strategies against GI helminthes.  相似文献   

4.
Trypanosoma evansi infection (surra) causes significant losses in livestock production in tropical and sub-tropical areas. The current ELISA recommended by OIE for diagnosis of the disease is based on trypanosome lysate antigen. However, antigenic variation and unstable nature of cell lysate antigen make it difficult to standardize the assay. Thus, there are needs to develop recombinant antigen-based ELISA that improve stability, sensitivity, and specificity of the test. Since tandem repeat (TR) proteins of trypanosomatid parasites generally possess high antigenicity, they have been considered to be the promising antigens for trypanosomosis and leishmaniosis. In this study, IgG responses against 14 recombinant TR proteins of trypanosomes were examined by ELISA. Serum samples were obtained from three water buffaloes experimentally infected with T. evansi. Since Trypanosoma congolense GM6 (TcoGM6) elicited highest IgG responses to all water buffaloes, we further bioinformatically and molecular biologically identified Trypanosoma brucei brucei GM6 (TbbGM6) and T. evansi GM6 (TeGM6) TR genes, respectively. As expected, predicted amino acid sequences of TbbGM6 and TeGM6 were identical while the nucleic acid sequence homology between TbbGM6 and TcoGM6 was 63.8%. All buffaloes became clearly positive in recombinant TbbGM6 (rTbbGM6)-based ELISA at 48 days post-infection, suggesting that rTbbGM6 is usable as a serodiagnostic antigen for chronic T. evansi infection.  相似文献   

5.
This paper reports on changes in the lymphocyte composition of the peripheral blood in sheep infected with Trypanosoma evansi. In addition, parasite-specific IgG1 and IgM antibody responses were monitored using a double-sandwich enzyme-linked immunosorbent assay (ELISA) technique. Eight sheep were infected with 2 × 106 T. evansi TREU 2143. The infection was characterised by chronicity and ended in self-cure in two of the sheep. These two sheep were designated group A, whereas the other six sheep, which remained parasitaemic until treated, were designated group B. Analysis of the peripheral blood lymphocytes (PBLs) by indirect immunofluorescence staining and flow cytometry revealed significant alterations in the numbers of T- and B-cell subsets detected in all infected sheep. In group A, whereas the numbers of CD8+ cells decreased, CD4+ cells showed marginal decreases, remaining at or above pre-infection figures and resulting in increase in the CD4:CD8 ratio. In group B, CD8+ cells showed few marginal decreases, being at or above pre-infection figures most of the time, whereas CD4+ cells decreased significantly from day 26 post infection (p.i.) such that the CD4:CD8 ratio decreased. Infection also resulted in significant increases (P < 0.001) as of day 26 p.i. in circulating B-cells in group B as shown by the numbers of sIg+, CD45R+, CD1+ and major histocompatibility complex (MHC) II+ cells. The increases, however, were moderate and biphasic in group A. T. evansi-specific IgM and IgG1 antibody isotypes were detected in all infected sheep, but their levels were significantly higher in group A than in group B (IgM P <0.05; IgG1 P <0.01). In addition, although an initially higher level of IgM response was subsequently replaced by a higher level of IgG1 response in group A, this was never the case in group B until after drug treatment. Received: 16 May 1998 / Accepted: 17 June 1998  相似文献   

6.
A total of 20 random primers (10-mers) were used to amplify RAPD markers from the genomic DNA of four Trypanosoma brucei stocks from East and West Africa, four T. evansi stocks from Africa, Asia and South America and one T. equiperdum stock from Asia. Between 65 and 88 reproducible fragments ranging from 0.25 to 2.15 kb were generated from these stocks depending on the stock/primer combination. The similarity coefficient (SC) among the stocks of T. brucei from Kenya, Nigeria, Tanzania and Zambia ranged from 62.9% to 74.0% (average: 67.6%). The SC among the stocks of T. evansi from Kenya, China and Brazil was 76.4%–95.5% (average: 86.4%), while the SC between T. evansi stock from China and Brazil was 95.5%. For T. evansi and T. equiperdum, the SC among the stocks ranged from 81.2% to 94.4% (average: 87.6%). As for the SC among the stocks of T. brucei and T. evansi, it was found to be from 54.7% to 80.3% (average: 68.0%) and the SC among stocks of T. brucei and T. equiperdum was from 59.4% to 76.9% (average: 68.1%). Our results indicate that the stocks of T. evansi from China and from Brazil are more closely related to the stock of T. equiperdum from China than to the stocks of T. evansi isolated from Kenya and to the stocks of T. brucei. In addition, our results further support the hypothesis that T. evansi stocks from China and Brazil could have arisen from a single lineage. The possible evolution of T. evansi and T. equiperdum is also discussed.  相似文献   

7.
Blood samples were collected from 67 adult Iranian dromedary camels naturally infected with Mycoplasma spp, and a control group comprised 20 healthy dromedary camels. Haematological and serum biochemical parameters were measured using standard techniques. In Giemsa-stained peripheral blood smears, Mycoplasma appears attached to the surface of erythrocytes. In infected camels, the number of red blood cells, haemoglobin concentration and haematocrit (packed cell volume) significantly decreased (P < 0.05).With regard to the values of mean corpuscular volume and mean corpuscular hemoglobin concentration, a normocytic and normochromic anaemia was observed in infected camels. In infected camels, the concentration of serum glucose was significantly lower as compared with controls (P < 0.05).  相似文献   

8.
Trypanosoma evansi infection in the Philippines is frequently reported to affect the country’s livestock, particularly, the buffaloes. To assess the prevalence and intraspecific diversity of T. evansi in the country, blood samples from water buffaloes in different geographical regions were collected during an outbreak. T. evansi was detected in all 79 animals tested using PCR targeting the RoTat 1.2 VSG gene. Sequencing of the rDNA complete internal transcribed spacer (ITS) region including the 5.8S subunit showed high similarity (99–100%) between Philippine isolates and known T. evansi isolates in Genbank. Tree construction based on the same region confirmed the close relationship between Philippine and reported Thai isolates as compared to Egyptian isolates separated by relatively small genetic distances, 47 polymorphisms, despite the clustering in four branches. Overall, the results of this study prove genetic diversity within T. evansi species despite previous reports on limited heterogeneity among isolates worldwide.  相似文献   

9.
Introduction  Vitamin D3, which exerts its effect through vitamin D receptor (VDR), is known for its potent immunomodulatory activities. Associations between low serum vitamin D3 levels and increased risk of tuberculosis have been reported. Study Subjects and Methods  Plasma 1,25 dihydroxy vitamin D3 levels (1,25(OH)2 D3) and ex vivo levels of VDR protein from peripheral blood mononuclear cells were studied in 65 pulmonary tuberculosis (PTB) patients and 60 normal healthy subjects (NHS) using enzyme-linked immunosorbent assay-based methods. Using real-time polymerase chain reaction (PCR), induction of VDR, cathelicidin, and CYP27B1 mRNA were studied in live Mycobacterium tuberculosis-stimulated macrophage cultures treated with or without 1,25 dihydroxy vitamin D3. VDR and CYP27B1 (-1077 A/T) gene polymorphisms were studied using PCR-based methods. Results  1,25(OH)2 D3 were significantly increased (p = 0.0004), while ex vivo levels of VDR protein were significantly decreased in PTB patients (p = 0.017) as compared to NHS. 1,25(OH)2 D3 levels were not different between variant genotypes of CYP27B1. A trend towards decreased levels of VDR protein was observed among NHS with BsmI BB and TaqI tt genotypes compared to NHS with other genotypes. Relative quantification of mRNA using real-time PCR revealed increased VDR mRNA expression in live M. tuberculosis-stimulated culture in PTB patients (p < 0.01) than normal healthy subjects. Cathelicidin mRNA expression was significantly increased in vitamin D3-treated cultures compared to unstimulated and M. tuberculosis-stimulated culture in both patients (p < 0.001) and NHS (p < 0.05). Conclusions  The present study suggests that PTB patients may have increased 1,25(OH)2 D3 levels, and this might lead to downregulation of VDR expression. Decreased VDR levels could result in defective VDR signaling. Moreover, addition of 1,25(OH)2 D3 might lead to increased expression of cathelicidin which could enhance the immunity against tuberculosis.  相似文献   

10.
The biochemical changes associating Trypanosoma evansi infection in pregnant and non-pregnant camels were investigated. Based on pregnancy diagnosis and serological findings, camels were classified into four groups as non-pregnant healthy camels (N?=?6), non-pregnant camels infected with T. evansi (N?=?6), pregnant healthy camels (N?=?6), and pregnant camels infected with Trypanosoma evansi (N?=?8). The results revealed significant decreases (p?<?0.05) in serum total proteins, albumin and globulins levels, and significant increases (p?<?0.05) in serum total cholesterol and blood urea nitrogen (BUN) levels in pregnant camels infected with T. evansi compared with healthy pregnant camel. On the other hand, there were hyperproteinemia and hyperglobulinemia in healthy pregnant camel compared with non-pregnant camel. It could be concluded that the biochemical changes associating T. evansi infection in pregnant camels are hypoproteinemia, hypoalbuminemia, and hypoglobulinemia and increased serum total cholesterol and BUN levels.  相似文献   

11.
The process of isolation of the 27-kDa glycoprotein from the somatic antigen of Fasciola gigantica was standardized and the diagnostic potentiality was evaluated for the detection of bubaline fasciolosis by indirect enzyme-linked immunosorbent assay. Initially, the test was standardized using the sera from experimentally noninfected(n = 20) and infected (n = 5)animals. Further, the sensitivity and the specificity of the test were evaluated through the sera of buffaloes with different natural infections, i.e., F. gigantica (n = 8 animals), F. gigantica and Gastrothylax crumenifer(n = 15), F. gigantica and Gigantocotyle explanatum (n = 6), trematode infections other than F. gigantica (n = 9), only G. crumenifer (n = 36), only G. explanatum (n = 18), G. crumenifer and G. explanatum positive (n = 39), and PM negative (n = 102). All animals came from the slaughterhouses of Bareilly (Uttar Pradesh, India) and Patna (Bihar, India). The level of sensitivity observed in the present study was 81.0%, while 97–98% specificity against G. crumenifer, G. explanatum, or a mixed infection with both parasites was noted. The study showed F. gigantica prevalence rate of 18–20% in the buffaloes of the study area. Enzyme-linked immunosorbent assay with a 27-kDa glycoprotein could be a feasible diagnostic method for the early detection of bovine fasciolosis.  相似文献   

12.
In recent years, the emergence of highly pathogenic Trypanosoma evansi strains in the Philippines has resulted in substantial losses in livestock production. In this study, we isolated T. evansi from infected-water buffaloes in the Philippines and analyzed their virulence using mice and cattle. A total of 10 strains of T. evansi were isolated. Evaluation of the virulence of each strain using mice depicted significant differences among the strains in the prepatent period, the level of parasitemia, and the survival time of the infected animals. In mice infected with the highly pathogenic T. evansi, signs of excessive inflammation such as marked splenomegaly and increase more than 6-fold in the number of leukocytes were observed at 8 days post-infection. To study the virulence of the parasite strains in cattle (which are the common T. evansi hosts in Philippines), cattle were infected with the T. evansi isolates that showed high and low virulence in mice. The rate of parasite growth and the length of the prepatent periods were found to be similar to those observed in mice for the respective strains. The cattle infected with the highly pathogenic strain developed anemia and a marked decrease in leukocyte counts. To determine the cause of the pathological changes, we analyzed the expression levels of inflammatory cytokines and observed up-regulation of tumor necrosis factor-α in anemic infected cattle. Our findings suggest that the epidemic of T. evansi in the Philippines is characterized by T. evansi strains with varying virulences from low to very high pathogenicity in cattle.  相似文献   

13.
The goal of the present study was to evaluate the difference in the synovial fluid constituents in cattle, buffaloes, camels, and donkeys. A total number of 20 clinically healthy adult male animals (cattle (N?=?5), buffaloes (N?=?5), camels (N?=?5), and donkeys (N?=?5) were subjected to study. Synovial fluid samples were collected from the metacarpophalangeal joint under complete aseptic conditions. The samples were examined physically, cytologically, and biochemically. Synovial fluid analysis revealed significant variations in specific gravity, total leukocyte counts, total proteins, albumin, globulins, glucose levels, and alkaline phosphatase activity among investigated animal species.  相似文献   

14.
Methicillin-resistant Staphylococcus aureus (MRSA) strains from Finland covering years 1997–1999 were studied for the presence of Panton-Valentine leukocidin (PVL) gene loci, and the clinically well-defined community-acquired MRSA (CA-MRSA) strains (n = 108) also for staphylococcal chromosomal cassette mec (SCCmec) and multilocus sequence types (MLST). Only a minority (12%) of the CA-MRSA strains contained the PVL gene loci and possessed genotypes formerly described as typical to CA-MRSA strains. The majority of these strains were heterogenous by MLST and pulsed-field gel electrophoresis (PFGE) analysis but, however, harboured the SCCmec cassette type IV. In conclusion, it seems doubtful to consider only molecular characteristics such as the presence of PVL genes as definite markers for CA-MRSA strains. This data was partly presented at the 14th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID), May 1–4, 2004, Prague, Czech Republic, Poster no. P1014.  相似文献   

15.
The present study was carried out to determine the prevalence of Theileria annulata in large ruminants in Southern Punjab (Pakistan). Blood samples were collected from 144 large ruminants, consisting of 105 cattle and 39 buffaloes, from six districts of Southern Punjab including Multan, Layyah, Muzaffar Garh, Bhakar, Bahawalnagar, and Vehari. Data on the characteristics of the animals and herds were collected through questionnaires. The age of animals (P = 0.02), presence of ticks on animals (P = 0.02), and presence of ticks on dogs associated with herds (P = 0.05) were among the major risk factors involved in the spread of tropical theileriosis in the study area. Two different parasite detection techniques, PCR amplification and screening of Giemsa-stained slides, were compared, and it was found that PCR amplification is a more sensitive tool (19% parasite detection) as compared to smear scanning (3% parasite detection) for the detection of T. annulata. Twenty eight out of 144 animals produced the 721-bp fragment specific for T. annulata from five out of six sampling districts. Different blood (hemoglobin, glucose) and serum (ALT, AST, LDH, cholesterol) parameters of calves and cattle were measured and compared between parasite-positive and parasite-negative samples to assess the effect of T. annulata on the blood and serological profile of infected animals.  相似文献   

16.
The objective of this study was to evaluate the lipid peroxidation and the susceptibility of erythrocytes to in vitro peroxidation as indicators of oxidative damage in erythrocytes and their roles in the pathogenesis of anemia during experimental Trypanosoma evansi infection in cats. Animals were divided into two groups: control and infected with T. evansi. Seven cats were infected with 108 trypomastigotes each, and parasitemia was estimated daily for 49 days by microscopic examination of smears. Hematological and biochemical parameters were evaluated for monitoring of the disease. Plasma lipid peroxidation (Thiobarbituric Acid Reactive Substances (TBARS)) and the susceptibility of erythrocytes to in vitro peroxidation were evaluated. Blood samples for analysis were collected at days 21 and 49 post-inoculation. TBARS level, indicated by MDA concentration, was higher in the infected group than in the control group in both analyzed periods, as well as the in vitro erythrocyte peroxidation (P < 0.001). The infected cats had variable degrees of regenerative anemia, which could be explained by the damage in erythrocyte membrane caused by lipid peroxidation.  相似文献   

17.
The present study was aimed at developing a SYBR Green™-based real-time polymerase chain reaction (PCR) assay for a rapid differentiation of the genotype G1 from the cluster of genotypes G2/G3 of Echinococcus granulosus, using as marker the 12S mtDNA gene. Eleven hydatid cysts from water buffaloes and 19 from cattle were used. Fourteen samples (identified as G1 using sequencing) showed a mean melting temperature (T m) of 76.4°C and 16 samples (identified as G2/G3 using sequencing) showed a mean T m of 77.0°C. The detected mean difference of the T m of 0.6°C between G1 and G2/G3 genotypes might allow a fast and simple discrimination of these genotypes. In conclusion, the real-time PCR developed in the present study provides a powerful tool for molecular studies on E. granulosus with possibilities for extension to other genotypes using different molecular targets. Maria Paola Maurelli and Laura Rinaldi contributed equally to this work.  相似文献   

18.
A total of 15 mixtures involving 9 different stocks attributed to the 19/20, 32 and 39 major clonal genotypes of Trypanosoma cruzi were used to infect third-instar nymphs of Triatoma infestans via an artificial feeding device. Three biological parameters were considered: (1) the percentage of infected insects (%II), (2) the number of flagellates per insect (NFI), and (3) the percentage of trypomastigotes per insect (%DIF). Genetic characterization by both multilocus enzyme electrophoresis (MLEE) and random amplification of polymorphic DNA (RAPD) indicated that in almost all cases (87%), mixtures remained present after completion of the whole cycle in the insect vector. Two lines of comparison were performed: (1) pure clonal genotypes versus corresponding mixed clonal genotypes and (2) the␣actual behavior of mixed clonal genotypes versus the expected behavior of the theoretical mixture (i.e. the␣arithmetic mean of the results observed for each of the two clonal genotypes taken separately). Statistical analyses of the variables were made difficult because of the presence of large standard deviations. Nevertheless, in several cases, mixtures differed significantly from pure clonal genotypes, and in one case the actual mixture differed significantly from the theoretical mixture. In some cases, interaction (either potentialization or reciprocal inhibition) could be suspected. Received: 10 March 1997 / Accepted: 21 September 1997  相似文献   

19.
We compared 12 stocks of Trypanosoma evansi and 1 recently isolated stock of Trypanosoma equiperdum from different regions of China by analysis of kinetoplast DNA (kDNA), nuclear DNA and molecular karyotypes. The T. equiperdum stock was remarkably similar to the T. evansi stocks, except for the possession of kDNA maxi-circles, suggesting a very close evolutionary relationship between T. evansi and T. equiperdum. The maxi-circles of the Chinese T. equiperdum stock were approximately 14.3 kb in size, i.e., about half the size of those of Trypanosoma brucei. This stock is thus similar to an old laboratory stock of T. equiperdum, which also has maxi-circles with a sizeable deletion. Both T. equiperdum and T. evansi kDNA mini-circles hybridised with a T. evansi-specific mini-circle fragment isolated from a Kenyan T. evansi stock. Our results extend the generality that T. evansi and T. equiperdum mini-circles are microheterogeneous rather than homogeneous. Molecular karyotypes obtained by pulsed field gradient gel electrophoresis provided a more sensitive way of distinguishing the T. evansi stocks than isoenzymes or restriction fragment length polymorphisms in kDNA mini-circles, genes for ribosomal RNAs and variant surface glycoproteins. Our results fit the general idea that T. evansi stocks worldwide have a single origin.  相似文献   

20.
Haematological parameters of 28 pregnant camels (Camelus dromedarius) were compared with those of 32 non-pregnant camels (C. dromedarius). The parameters compared were: total erythrocytes count (RBC), haemoglobin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and total leucocyte count (TLC). Results obtained indicate that RBC, Hb and PCV decreased in the later stages of pregnancy while TLC remained unchanged. Calculated indices revealed a significant increase in MCV (p < 0.02) of pregnant camels.  相似文献   

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