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Background:Tuberculosis infection still represents a global health issue affecting patients worldwide. Strategies for its control may be not as effective as it should be, specifically in case of resistant strains of M.tb. In this regard, the role of mycobacterial MTases in TB infection can be fundamental, though it has not been broadly deciphered. Methods:Five resistant isolates of M.tb were obtained. M.tb H37Rv (ATCC 27249) was used as a reference strain. Seven putative mycobacterial MTase genes (Rv0645c, Rv2966c, Rv1988, Rv1694, Rv3919c, Rv2756c, and Rv3263) and Rv1392 as SAM synthase were selected for analysis. PCR-sequencing and qRT-PCR were performed to compare mutations and expression levels of MTases in different strains. The 2-ΔΔCt method was employed to calculate the relative expression levels of these genes.Results:Only two mutations were found in INHR strain for Rv3919c (T to G in codon 341) and Rv1392 (G to A in codon 97) genes. Overexpression of Rv0645c, Rv2756c, Rv3263, and Rv2966c was detected in all sensitive and resistant isolates. However, Rv1988 and Rv3919c decreased and Rv1694 increased in the sensitive strains. The Rv1392 expression level also decreased in INHR isolate.Conclusion:We found a correlation between mycobacterial MTases expression and resistance to antibiotics in M.tb strains. Some MTases undeniably are virulence factors that specifically hijack the host defense mechanism. Further evaluations are needed to explore the complete impact of mycobacterial MTases within specific strains of M.tb to introduce novel diagnosis and treatment strategies.Key Words: Drug resistance, Methyltransferases, Mycobacterium tuberculosis, S-adenosylmethionine  相似文献   
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Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne's disease in ruminants and may contribute to Crohn's disease in humans. The aim of this study was to determine the occurrence and quantity of MAP in cattle feces and milk in the Iranian context. In addition, we evaluated the effect of cattle age as well as farming system as risk factors contributing to MAP load. For this, a total sample of 373 consisting of 150 cattle feces (CF), 150 individual cow's milk (ICM), as well as 73 bulk-tank milk (BTM) was collected randomly and regardless of the cattle health status. The samples were assayed using F57 quantitative real-time PCR (qPCR) and culture method. According to the results of qPCR which was found ∼10 times more sensitive than culture assay, MAP was detected in 68.66% (103/150) of the CF, 12% (18/150) of the ICM and 52.05% (38/73) of the BTM samples. In contrast to the previous reports, the quantity of MAP in the BTM (2.03–5.97 log cfu/50 ml) was statistically (p < 0.01) higher than the ICM (0.90–1.97 log cfu/50 ml). Data suggested a direct relation (p < 0.01) between the cattle age and the quantity of MAP in the CF samples, while the relation was not statistically significant (p > 0.05) for the ICM. In addition, MAP load in the BTM samples obtained from traditional farms was significantly (p < 0.01) higher than that of the industrial ones, while the differences in CF and ICM was not significant (p > 0.05).  相似文献   
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Despite the numerous potential applications of oocyte cryopreservation, the poor success rate has limited its practical applications. In livestock, particularly in ovine, the oocytes have low developmental competence following vitrification/warming process. Considering the occurrence of osmotic and oxidative stresses during the vitrification/warming process, the application of antioxidants and osmolytes may improve the developmental competence of vitrified/warmed oocytes. In the present study, we aimed to evaluate the effects of the addition of ascorbic acid (AA) and N‐acetyl cysteine (NAC) as antioxidants and glycine as an organic osmolyte either to the vitrification/warming solutions (VWS) or to the IVM medium on the developmental competence of vitrified/warmed ovine germinal vesicle stage oocytes. The survival rate in the vitrified groups was significantly lower than fresh ones. In vitrified/warmed oocytes, there was no significant difference in survival rate between supplemented and non‐supplemented groups. The addition of AA and/or NAC to the VWS or IVM medium and adding glycine to the IVM medium reduced the proportion of apoptotic oocytes and fragmented embryos, which was reflected as an increase in the proportions of metaphase II stage oocytes and blastocyst production. The best result was achieved by supplementing the IVM medium with NAC. In our study condition, antioxidants and glycine could improve the developmental competence of vitrified/warmed ovine immature oocytes, especially when added during IVM.  相似文献   
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From a series of studies on single nucleotide polymorphisms (SNPs) in the bovine growth hormone (GH) gene of Japanese Black cattle, the type‐C (127Val and 172Met) that is specific for this breed has been intensively focused upon because of the economic importance for carcass traits, such as intramuscular oleic acid contents. In the present study, we intended to analyze the 3‐D structure of GH of haplotype C, and developed a novel method to detect the type C gene. Three‐D analysis of the type C protein showed that the amino acid residues (127Val and 172Met), which are present in the third and fourth helixes, respectively, and are important for binding with GH receptors, are shifted to deeper positions in the molecule compared with that for type A (127Leu and 172Thr), implying the alteration of binding interaction with receptors. A novel, efficient and cost‐effective method (Dot‐blot‐SNP technique) for type C genotyping was successfully established, of which the basal method was a reported genotyping of SNPs for a large number of plants, reducing the cost to 10% or less of direct sequencing.  相似文献   
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A 12‐week feeding trial was conducted to determine a suitable carbohydrate source and form for Pangasianodon hypophthalmus. Ten isoenergetic, isonitrogenous and isolipidic diets, including five carbohydrate sources (dextrin, potato starch, wheat starch, corn starch and sago starch) and two carbohydrate forms (raw and cooked), were formulated. Results showed that specific growth rate, weight gain percentage, whole‐body lipid and 6‐phosphogluconate dehydrogenase enzyme activity of fish fed with cooked carbohydrates were significantly lower (p < .05) than those fed with raw carbohydrates (p < .05). Similarly, the fatty acid synthase enzyme activity of fish fed with the cooked form of carbohydrates was significantly lower (p < .05) than that fed with the raw form of carbohydrates except fish fed with cooked potato starch. The blood glucose level and malic enzyme activity of fish fed with cooked carbohydrate were significantly (p < .05) higher than those fed with raw carbohydrate. In summary, this study showed that cooked starch is an unsuitable dietary carbohydrate form for Pangasianodon hypophthalmus fingerlings. The raw forms of dextrin starch and potato are suitable dietary carbohydrate sources for further scientific studies on the carbohydrate utilization of P. hypophthalmus.  相似文献   
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The management of an Anterior Cruciate Ligament (ACL) avulsion is principally by surgery. There are two major techniques in this regard; fixation through open surgery (arthrotomy) or arthroscopically-assisted repair. These are not new in the literature; however, the debate regarding the better approach is still under debate. This study focused on comparing outcome and consequences of arthroscopically-assisted vs. open surgery in repairing ACL avulsion. In a randomized clinical trial, 44 patients with unilateral ACL avulsion were recruited in Tabriz Shohada teaching Centre during a 12 month period of time. These patients were randomized in two equal age and sex-matched groups underwent either arthroscopically-assisted or open ACL repair. The constructive technique was the same in both groups without using any graft. The minimum follow-up period was 6 months including 3 weeks, 3 months and 6 months postoperatively. Range of Motion (ROM), laxity, Anterior Drawer Test (ADT) result, duration of hospital stay, wound status, nonunion and return to previous work were compared between the two groups. Mean time of suture removal (p = 0.10), minimum and maximum ROM at months 3 (p = 0.43 and 0.22, respectively) and 6 (p = 0.73 and 0.77, respectively), ADT at months 3 and 6 (p = 0.16 for both), laxity at month 6 (p = 0.28) and wound status at week 3 (p = 0.35) were not significantly different between the two groups. There was no case of nonunion at month 6 in either group. The mean hospital stay was significantly shorter in the arthroscopy group (3.77 +/- 0.92 vs. 2.50 +/- 0.51 days; p < 0.001). The mean laxity score was significantly higher in the open surgery group at month 3 (4.82 +/- 0.59 vs. 4.45 +/- 0.60; p = 0.05). The rate of nonunion was significantly higher in the open surgery group at month 3 (40.9% vs. 9.1%; p = 0.02). Patients in the arthroscopically-assisted technique group returned sooner to previous work (17.41 +/- 1.53 vs. 14.82 +/- 0.96 weeks; p < 0.001). Based on our results, arthroscopically-assisted reconstruction of ACL avulsion is superior to open surgery.  相似文献   
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Journal of Plant Diseases and Protection - Pot experiments with winter wheat were conducted for two successive years to study the relationship between the cereal cyst nematode, Heterodera...  相似文献   
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Eurasian Soil Science - Knowledge on P release characteristics and availability of different forms of soil phosphorus can be useful for crop production. Kinetics of P release and distribution of...  相似文献   
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