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This study illustrated the immunohistochemical distribution of androgen and vitamin D receptors of epididymis in 20 sexually mature ram (Rahmani breed) with average age ranged from (2_4) years and average weight ranged from (50_65kg). Androgen receptor was localized in the cytoplasm of both ciliated and non ciliated cells of efferent ductules, besides the principal cells via the entire epididymal duct. The principal cells of both corpus and proximal cauda epididymis showed the highest immunoreactivity to androgen receptors. Furthermore, vitamin D receptor was localized in the cytoplasm of all epithelium of the efferent ductules besides principal cells of all epididymal regions, however the immunoreaction was significantly higher in the efferent ductules, distal caput and distal cauda epididymis. In conclusion, these results suggest that the function of ram epididymis is regulated by both androgen and Vitamin D.  相似文献   
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Calf diarrhea is one of the major health challenges in cattle herds. The bacteriological examination of fecal samples collected from apparently healthy and diarrheic calves' revealed isolation of 26 E. coli isolates out of 56 calves with an incidence of 46.4%. Serogroups O1, O26, O44, O55, O115, O119, O125, O146, and O151 were identified from the collected fecal samples. Using PCR all isolates was positive for ompA gene species specific for E. coli. While stx1 and eaeA genes detected with incidence of 3.8 and 19.2% respectively from the isolates. The presence of stx2 gene was negative in the fecal isolates. Among colostrum samples 4 E. coli isolates were detected and serogrouped to O26, O55 and O119. They were negative for eaeA, stx1 and stx2 except strain number 4 (O55) was positive for stx1. E. coli strains were sensitive to norfloxacin (80.7%) and resistant to ampicillin and cefotaxime (100% each). Based on our findings, there was no association between occurrence of E. coli and age of calf (2–14 days), while bottle feeding calf colostrum may be a source of E. coli contamination.  相似文献   
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Acinetobacter baumannii (A. baumannii) is one of the most common Gram-negative pathogens that represent a major threat to human life. Because the prevalence of Multidrug-resistant biofilm-forming A. baumannii is increasing all over the world, this may lead to outbreaks of hospital infections. Nonetheless, the role of raw meat as a reservoir for A. baumannii remains unclear. Here our research was aimed to exhibit the frequency, precise identification, and genotyping of biofilm-related genes as well as antimicrobial resistance of A. baumannii isolates of raw meat specimens. Fifty-five A. baumannii strains were recovered from 220 specimens of different animal meat and then identified by Peptide Mass Fingerprinting Technique (PMFT). All identified isolates were genotyped by the qPCR method for the existence of biofilm-related genes (ompA, bap, blaPER-1, csuE, csgA, and fimH). In addition, the antimicrobial resistance against A. baumannii was detected by the Kirby-Bauer method. Based on our findings, the frequency rate of 55 A. baumannii isolates was 46.55%, 32.50%, 15.00%, and 9.68% of sheep, chicken, cow, and camel raw meat samples, respectively. The PMFT was able to identify all strains by 100%. the percentages of csuE, ompA, blaPER-1, bap, and csgA genes in biofilm and non-biofilm producer A. baumannii were 72.73%, 60%, 58.2%, 52.74%, and 25.45%, respectively. In contrast, the fimH was not detected in all non-biofilm and biofilm producer strains. The ompA, bap, blaPER-1, csgA were detected only in biofilm-producing A. baumannii isolates. The maximum degree of resistance was observed against amoxicillin/clavulanic acid (89.10%), gentamicin (74.55%), tetracycline (72.73%), ampicillin (65.45%), and tobramycin (52.73%). In conclusion, our investigation demonstrated the high incidence of multi-drug resistant A. baumannii in raw meat samples, with a high existence of biofilm-related virulence genes of ompA, bap, blaPER-1, csgA. Therefore, it has become necessary to take the control measures to limit the development of A. baumannii.  相似文献   
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Significant interest in studying the lipooligosaccharide (LOS) of Campylobacter jejuni has stemmed from its potential role in postinfection paralytic disorders. In this study we present the results of PCR screening of five LOS locus classes (A, B, C, D, and E) for a collection of 116 C. jejuni isolates from chicken meat (n = 76) and sporadic human cases of diarrhea (n = 40). We correlated LOS classes with clonal complexes (CC) assigned by multilocus sequence typing (MLST). Finally, we evaluated the invasion potential of a panel of 52 of these C. jejuni isolates for Caco-2 cells. PCR screening showed that 87.1% (101/116) of isolates could be assigned to LOS class A, B, C, D, or E. Concordance between LOS classes and certain MLST CC was revealed. The majority (85.7% [24/28]) of C. jejuni isolates grouped in CC-21 were shown to express LOS locus class C. The invasion potential of C. jejuni isolates possessing sialylated LOS (n = 29; classes A, B, and C) for Caco-2 cells was significantly higher (P < 0.0001) than that of C. jejuni isolates with nonsialylated LOS (n = 23; classes D and E). There was no significant difference in invasiveness between chicken meat and human isolates. However, C. jejuni isolates assigned to CC-206 (correlated with LOS class B) or CC-21 (correlated with LOS class C) showed statistically significantly higher levels of invasion than isolates from other CC. Correlation between LOS classes and CC was further confirmed by pulsed-field gel electrophoresis. The present study reveals a correlation between genotypic diversity and LOS locus classes of C. jejuni. We showed that simple PCR screening for C. jejuni LOS classes could reliably predict certain MLST CC and add to the interpretation of molecular-typing results. Our study corroborates that sialylation of LOS is advantageous for C. jejuni fitness and virulence in different hosts. The modulation of cell surface carbohydrate structure could enhance the ability of C. jejuni to adapt to or survive in a host.Campylobacter jejuni is an important human enteric pathogen worldwide (3, 7, 26). Infected humans exhibit a range of clinical spectra, from mild, watery diarrhea to severe inflammatory diarrhea (28). Factors influencing the virulence of C. jejuni include motility, chemotaxis, the ability to adhere to and invade intestinal cells, intracellular survival, and toxin production (28, 30, 52). Besides its role in human enteric illnesses, C. jejuni is a predominant infectious trigger of acute postinfectious neuropathies, such as Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS) (1). Significant interest in studying the structure and biosynthesis of the core lipooligosaccharide (LOS) of C. jejuni has resulted from its potential role in these paralytic disorders. Many studies have now provided convincing evidence that molecular mimicry between C. jejuni LOS and gangliosides in human peripheral nerve tissue plays an important causal role in the pathogenesis of GBS/MFS (16, 17, 19, 21).Initial comparative studies of C. jejuni LOS structure and the corresponding DNA sequences of the LOS biosynthesis loci identified eight different LOS locus classes. Three of these classes, A, B, and C, harbor sialyltransferase genes involved in incorporating sialic acid into the LOS (42). Sialylation of the LOS core was found to be associated with ganglioside mimicry and also to affect immunogenicity and serum resistance (21). Recently, Parker et al. (43) identified 11 additional LOS classes on the basis of the sequence at the LOS biosynthesis locus. Their investigation also suggested that the LOS loci of C. jejuni strains are hot spots for genetic exchange, which can lead to mosaicism.Despite evidence on locus variation within C. jejuni LOS classes, PCR-based screening of a collection of 123 clinical and environmental strains showed that almost 60% of C. jejuni strains belong to class A, B, or C (42). Additionally, Godschalk et al. (16) found that 53% (9/17) of GBS-associated C. jejuni strains possessed LOS of class A, while 64% (35/55) of the non-GBS-associated isolates possessed LOS of class A, B, or C, and 62% (13/21) of enteritis-associated Campylobacter strains expressed LOS of class A, B, or C, as well. This relative representation of sialylated LOS classes A, B, and C was hypothesized to be advantageous for C. jejuni in the colonization and infection of various hosts (42, 49). Recently, Louwen et al. (34) demonstrated that C. jejuni strains possessing sialylated LOS (class A, B, or C) invade Caco-2 cells significantly better than nonsialylated strains (with class D or E). Knockout mutagenesis of the LOS sialyltransferase Cst-II in three C. jejuni strains revealed a significant reduction in the invasion potentials of the mutant strains (34). The possible role of LOS in adhesion and invasion was previously highlighted in the work of Perera et al. (44) and Kanipes et al. (29), where a C. jejuni waaF mutant strain showed significant reductions in levels of adherence to and invasion of INT-407 cells.LOS class diversity in C. jejuni strains isolated from chicken meat, an important source of human campylobacteriosis (6, 7, 26), has hardly been studied at all. In addition, the role of LOS class variation in the invasion potential of C. jejuni strains from chicken meat still needs to be explored. The epidemiological relevance of C. jejuni LOS gene screening can be further elaborated by correlating its results with results from other molecular-typing tools (e.g., multilocus sequence typing [MLST] and pulsed-field gel electrophoresis [PFGE]). In the present study, we screened a diverse collection of C. jejuni isolates, from consumer-packaged chicken meats and from sporadic human cases of diarrhea, by PCR for five LOS classes (A, B, C, D, and E). Then we correlated the LOS classes assigned by PCR screening with the genotypes assigned by PFGE and MLST. Finally, we tested the invasion potentials of a representative subset of C. jejuni isolates in relation to their LOS classes and genotypic diversity.  相似文献   
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This study evaluates the antimicrobial effects of ethanolic extract of five herbal plants; Guava (Psidium guajava), Sage (Salvia officinalis), Rhamnus (Ziziphusspina Christi), Mulberry (Morusalba L.), and Olive (Oleaeuropaea L) leaves against several microbial population representing Gram positive, Gram negative and Mollicutes; S. aureus, E. coli, Pasteurella multocida, B. cereus, Salmonella Enteritidis and M. gallisepticum using standard agar disc diffusion technique and minimal inhibitory concentration (MIC). Different extracts reveal variable results against the microorganism under study. All extracts have no antibacterial potency for Mycoplasma gallisepticum except Psidium guajava. The results of minimal inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the extracts against the six bacteria ranged from 625 to 5000 μg/ml. The used herbal extract could inhibit the selected microorganism under study with variable minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC).  相似文献   
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Livin is a member of the Inhibitor of Apoptosis Protein family which inhibits apoptosis induced by a variety of stimuli. We previously identified Livin and demonstrated that following apoptotic stimuli, Livin is cleaved by effector caspases to produce a truncated form with paradoxical pro-apoptotic activity. In the present study, we reveal that while full-length Livin shows diffuse cytoplasmic localization, truncated Livin (tLivin) is found in a peri-nuclear distribution with marked localization to the Golgi apparatus. Using mutation analysis, we identified two domains that are crucial for the pro-apoptotic activity of tLivin: the N-terminal region of tLivin which is exposed by cleavage, and the RING domain. We demonstrate that, of the N-terminal sequence, only the first N-terminal glycine residue dictates the peri-nuclear distribution of tLivin. However, while the perinuclear localization of tLivin is essential, it is not sufficient for tLivin to exert its pro-apoptotic function. Once tLivin is properly localized, an intact RING domain enables its pro-apoptotic function. Electronic Supplementary Material Supplementary material is available in the online version of this article at .  相似文献   
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The prevalence of obesity is increasing at an alarming rate, but, unfortunately, only a few drugs are currently available on the market. In the present study, the methanolic extract of Ginkgo biloba L. (Ginkgoaceae) was investigated as an inhibitor of pancreatic lipase (PL) in an attempt to explain its hypolipidaemic activity. In vitro assay of G. biloba leaves extract revealed a substantial PL inhibition activity (IC(50)?=?16.5 μg/mL). Further investigation was performed by employing theoretical docking simulations and experimental testing to uncover the active constituents responsible for G. biloba anti-lipase activity. Virtually, terpene trilactones, including ginkgolides and bilobalide, were found to fit within the binding pocket of PL via several attractive interactions with key amino acids. Experimentally, ginkgolides A, B, and bilobalide were found to inhibit PL significantly (IC(50)?=?22.9, 90.0, and 60.1 μg/mL, respectively). Our findings demonstrated that the hypolipidaemic effects of G. biloba extract can be attributed to the inhibition of PL by, at least in part, terpene trilactones. In conclusion, this work can be considered a new step towards the discovery of new natural safe hypolipidaemic PL inhibitors.  相似文献   
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