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31.
Mishra A Singhal A Chauhan DS Katoch VM Srivastava K Thakral SS Bharadwaj SS Sreenivas V Prasad HK 《Journal of clinical microbiology》2005,43(11):5670-5678
Mycobacterium tuberculosis and M. bovis infect animals and humans. Their epidemiologies in developed and developing countries differ, owing to differences in the implementation of preventive measures (World Health Organization, 1999). Identification and differentiation of these closely related mycobacterial species would help to determine the source, reservoirs of infection, and disease burden due to diverse mycobacterial pathogens. The utility of the hupB gene (Rv2986c in M.tuberculosis, or Mb3010c in M.bovis) to differentiate M. tuberculosis and M. bovis was evaluated by a PCR-restriction fragment length polymorphism (RFLP) assay with 56 characterized bovine isolates (S. Prabhakar et al., J. Clin. Microbiol. 42:2724-2732, 2004). The degree of concordance between the PCR-RFLP assay and the microbiological characterization was 99.0% (P < 0.001). A nested PCR (N-PCR) assay was developed, replacing the PCR-RFLP assay for direct detection of M. tuberculosis and M. bovis in bovine samples. The N-PCR products of M. tuberculosis and M. bovis corresponded to 116 and 89 bp, respectively. The detection limit of mycobacterial DNA by N-PCR was 50 fg, equivalent to five tubercle bacilli. M. tuberculosis and/or M. bovis was detected in 55.5% (105/189) of the samples by N-PCR, compared to 9.4% (18/189) by culture. The sensitivities of N-PCR and culture were 97.3 and 29.7, respectively, and their specificities were 22.2 and 77.7%, respectively. The percentages of animals or samples identified as infected with M.tuberculosis or M. bovis by N-PCR and culture reflected the clinical categorizations of the cattle (P of <0.05 to <0.01). Mixed infection by N-PCR was detected in 22 animals, whereas by culture mixed infection was detected in 1 animal. 相似文献
32.
Mishra S Pattnaik D Mahapatra A Swain B 《Indian journal of pathology & microbiology》2004,47(1):75-76
In a 35 year old immunocompetent male, clinically diagnosed as a case of hydropneumothorax of left side, Salmonella typhi was isolated as the causative agent of pleural empyema. 相似文献
33.
34.
M. Mishra U. N. Pathak A. B. Khan 《International journal of experimental pathology》1981,62(5):526-528
Twelve albino rabbits of either sex weighing 1.0-1.25 kg were fed a standard laboratory diet of green grass and sattu (roasted Bengal gram). After a 2-week run-in period their serum cholesterol levels were estimated. All animals were now fed 0.5 g cholesterol and 1.0 g clarified butter daily and were not divided into 3 groups of 4 animals each. While all received the standard cholesterol-rich diet, Group A animals received no additional substances, animals in Group B were each fed 10 mg vitamin C daily, while those in Group C were each given 1.0 g fresh Amla (Emblica officinalis Gaertn). Mean serum cholesterol levels in all three groups rose to significantly higher levels by the end of the second week. There was a further rise by the end of the third and fourth weeks in Groups A and B. However, animals in Group C (i.e. those given Amla) showed significantly lower mean serum cholesterol levels at the end of the second week than their counterparts in Groups A and B. At the end of the third and fourth weeks the differences were even more pronounced. 相似文献
35.
Hemagglutinin activity (HA) was studied in the midgut extracts from highly (h) and lowly susceptible strains of Aedes aegypti mosquitoes to Dengue-2 virus (DEN-2). HA in the midgut extracts from these two isofemale strains of mosquitoes was high in as compared to (h) mosquitoes. HA was found to be higher with chicken red blood cells (RBCs) than with rabbit and human RBCs of O group. Larval midgut extracts showed higher activity than those from adult female mosquitoes. Exposure of midgut extracts to 100 degrees C for 10 mins destroyed the activity. The activity was observed between pH 6 and pH 10. HA in midgut extracts was also studied using twenty different carbohydrates; five of them showed an inhibition of HA. The inhibitory carbohydrates, when incorporated into DEN-2-infected bloodmeal, showed a reduction in the susceptibility of mosquitoes to the virus as compared to the control ones fed on the virus alone. Similarly, when these carbohydrates were incorporated in the DEN-2-infected inoculum, the inoculated mosquitoes showed a reduction in the susceptibility to the virus. HA in the virus-infected midgut extracts was higher than that in the uninfected controls. These results suggest that the presence of HA in the midgut may be one of the factors that affect the susceptibility of Ae. aegypti mosquitoes to DEN-2. 相似文献
36.
The immunodiagnosticum for this test was prepared extempore by mixing blue color dyed latex beads (1% suspension) with equal volume of diluted anti-teliospore serum. This test was considered to be better for the detection of solubilized teliosporic antigens over intact teliospores of Karnal bunt. The teliosporic antigens solubilized using sonication and detergent extraction were used for the standardization of the test by optimizing the dilution of latex bead suspension and determining the detection limits. For determining the sensitivity of test, antigen concentration kinetics analysis was performed by adding 15 µl of antibodies sensitized latex beads to 15 µl of different concentrations of solubilized antigens on glass slide. The detection limit of this test was 7.5 µg solubilized teliosporic antigens equivalent to 750 teliospores and suitable for single seed analysis. Small agglutinin formation with solubilized antigen of Puccinia recondita and T. barclayana interpreted on the basis of partial cross reactivity of immunodignosticum with these pathogens. However, no cross reactivity was found with teliosporic antigen(s) of spores of Curvularia lunata, Ustilaga tritici, Helminthosporium sativum, Ustilaginoidea vircns and Alternaria triticina. 相似文献
37.
The source and nature of zona lytic factors during zona escape of hamster blastocyts were investigated. When cultured in hamster embryo culture medium (HECM)-2h, all 8-cell embryos (n = 135) developed to zona escaped-blastocysts with complete zona lysis. In addition, 2-cell embryos, when co-cultured with zona escaping-blastocysts (at a ratio of 1:10), exhibited zona lysis. Various other embryos at the 1-8-cell stages also showed zona lysis when cultured with zona-escaping blastocysts. However, zonae from mice, rats, sheep and humans were resistant to lysis under these conditions. Pronase treatment resulted in rapid zona lysis in hamsters (7 +/- 1 s), whereas in other species zona lysis was much slower: mouse (662 +/- 27 s), rat (532 +/- 16 s), sheep (120 +/- 12 s) and human (104 +/- 8 s). When cysteine protease inhibitors (antipain, leupeptin, E-64 and p-hydromercuricbenzoate) were tested, they completely inhibited zona escape, while trypsin inhibitors (TLCK and SBTI) did not. Uterine zona lysin contribution in zona escape was discounted since: (i) uterine luminal flushing and endometrial extract from day 4 (the time of zona escape in vivo) pregnant females failed to lyse zonae and (ii) endogenous oocytes and transferred 2-cell embryos (to day 3 pseudopregnant recipients) were all zona-intact, while 71% of transferred blastocysts exhibited zona escape, following their recovery after 24 h. These observations suggest that a species-specific, embryonic proteolytic factor, with a cysteine protease-like activity, is involved in the zona escape of blastocysts in hamsters. 相似文献
38.
Acrylic acid (AA) was polymerized with NO2 in tetrahydrofuran (THF) and in 1,4-dioxane. The effects of monomer and initiator concentration and of temperature on polymer conversion, initial rate of polymerization, and molecular weight were studied. The overall activation energy of polymerization was found to be 16,3 kcal mol?1 (68,23 kJ · mol?1) and 15,54 kcal · mol?1 (65,05 kJ · mol?1) in THF and in 1,4-dioxane, respectively. High molecular weight polymers (M ca. 105) were obtained. The polymerization appears to be initiated by free radicals. 相似文献
39.
40.
Effect of nitration on protein tyrosine phosphatase and protein phosphatase activity in neuronal cell membranes of newborn piglets 总被引:2,自引:0,他引:2
Protein tyrosine phosphatase predominantly determines the status of protein tyrosine kinase-dependent phosphorylation of specific proteins and controls the survival and death of neurons. Previous studies have shown that protein tyrosine phosphatase activity is decreased during hypoxia in cortical membranes of the newborn piglet. We have also shown that nitric oxide (NO) free radicals are generated during hypoxia, and may result in modification of protein tyrosine phosphatase via peroxynitrite-mediated modification. The present study tests the hypothesis that the hypoxia-induced decrease in protein tyrosine phosphatase activity is NO-mediated. To test this hypothesis, in vitro experiments were conducted by measuring protein tyrosine phosphatase activity in the presence of an NO donor, sodium nitroprusside (SNP), or peroxynitrite. Since 3-nitrotyrosine is produced as a consequence of peroxynitrite reactions, we have also examined the effect of 3-nitrotyrosine on protein phophatase activity. Cerebral cortical P(2) membranes were prepared from seven normoxic newborn piglets and each sample was divided into three aliquots: a control group, a SNP group (exposed to 200 microM SNP), and a peroxynitrite group (exposed to 100 microM peroxynitrite). Protein tyrosine phosphatase activity was determined spectrophotometrically in the presence or absence of 2 microM bpV(phen), a highly selective inhibitor of protein tyrosine phosphatase. The protein tyrosine phosphatase activity was 198+/-25 nmol/mg protein/h in the normoxic group, 177+/-30 nmol/mg protein/h in the SNP group (p=NS versus normoxic) and 77+/-20 nmol/mg protein/h in the peroxynitrite group (p<0.001 versus normoxic). The results show that peroxynitrite but not SNP exposure results in decreased protein tyrosine phosphatase activity in vitro. Furthermore 3-nitrotyrosine (100 microm), a product of peroxynitrite, decreased the enzyme activity from 926+/-102 to 200+/-77 (p<0.001). We conclude that protein tyrosine phosphatase regulation is mediated by peroxynitrite. We propose that hypoxia-induced NO production leading to peroxynitrite formation is a potential mechanism of protein tyrosine phosphatase inactivation in vivo. The NO-induced decrease in protein tyrosine phosphatase and protein phosphatase activity, leading to Bcl-2 protein phosphorylation and loss of its antiapoptotic activity may be a NO-mediated mechanism of programmed cell death in the hypoxic brain. 相似文献