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991.
Atteeq Ur Rehman Robert J. Morell Shahid Y. Khan Mohsin Shahzad Saima Riazuddin Sheikh Riazuddin 《American journal of human genetics》2010,86(3):378-388
Targeted genome capture combined with next-generation sequencing was used to analyze 2.9 Mb of the DFNB79 interval on chromosome 9q34.3, which includes 108 candidate genes. Genomic DNA from an affected member of a consanguineous family segregating recessive, nonsyndromic hearing loss was used to make a library of fragments covering the DFNB79 linkage interval defined by genetic analyses of four pedigrees. Homozygosity for eight previously unreported variants in transcribed sequences was detected by evaluating a library of 402,554 sequencing reads and was later confirmed by Sanger sequencing. Of these variants, six were determined to be polymorphisms in the Pakistani population, and one was in a noncoding gene that was subsequently excluded genetically from the DFNB79 linkage interval. The remaining variant was a nonsense mutation in a predicted gene, C9orf75, renamed TPRN. Evaluation of the other three DFNB79-linked families identified three additional frameshift mutations, for a total of four truncating alleles of this gene. Although TPRN is expressed in many tissues, immunolocalization of the protein product in the mouse cochlea shows prominent expression in the taper region of hair cell stereocilia. Consequently, we named the protein taperin. 相似文献
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Despite effective chemotherapy, schistosomiasis remains the second largest public health problem in the developing world. Currently, vaccination is the new strategy for schistosomiasis control. The presence of common antigenic fractions between Schistosoma mansoni and its intermediate host provides a source for the preparation of a proper vaccine. The objective of this paper is to evaluate the nucleoprotein extracted from either susceptible or resistant snails to protect against schistosomiasis. The vaccination schedule consisted of a subcutaneous injection of 50 μg protein of each antigen followed by another inoculation 15 days later. Analyses of marker enzymes for different cell organelles [succinate dehydrogenase, lactate dehydrogenase (LDH), glucose-6-phosphatase, acid phosphatase and 5'-nucleotidase] were carried out. Energetic parameters (ATP, ADP, AMP, phosphate potentials, inorganic phosphate, amino acids and LDH isoenzymes) were also investigated. The work was extended to record worm and ova counts, oogram determination in the liver and intestine and the histopathological pattern of the liver. The nucleoprotein of susceptible snails showed reduction in worm and ova counts by 70.96% and 51.31%, respectively, whereas the nucleoprotein of resistant snails showed reductions of 9.67% and 16.77%, respectively. In conclusion, we found that the nucleoprotein of susceptible snails was more effective in protecting against schistosomiasis. 相似文献
994.
Mohammad Reza Safarinejad Nayyer Shafiei Saba Safarinejad 《Molecular reproduction and development》2010,77(8):720-727
A considerable number of infertile men have no known mechanism for their infertility. This study aims to examine if there is an association between endothelial nitric oxide synthase (eNOS) T‐786C, G894T, and 4a/b gene polymorphisms and idiopathic male infertility. Three hundred fifty‐two men with idiopathic infertility (mean age 32.4 ± 11.4 years) and 356 healthy controls (mean age 33.2 ± 11.6 years) with documented fertility were recruited in this study. Genotypes for T‐786C, G894T, and 4a/b gene polymorphisms were identified by the polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) analysis. The eNOS ?786CC genotype (0.310 vs. 0.081; odds ratio (OR), 3.64; 95% confidence interval (CI), 2.28–4.46; P = 0.001), 894TT genotype (0.131 vs. 0.006; OR, 3.62; 95% CI, 2.68–4.87; P = 0.001) and 4aa genotype (0.128 vs. 0.009; OR, 2.82; 95% CI, 1.88–3.89; P = 0.004) were significantly more frequent in infertile subjects. Furthermore, there was a significant difference between the group of infertile patients with azoospermia and oligoasthenoteratozoospermia (OAT) when compared by genotype distribution (?786CC vs. 786TT, 894TT vs. 894GG, and 4aa vs. 4bb) (all P < 0.01). We also found an association between the eNOS “?786C,” “894T,” and “a” alleles and an increased risk of poor semen parameters. Our data revealed a significant relationship between eNOS genotypes and the phenotype of infertility. Mol. Reprod. Dev. 77: 720–727, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
995.
Sphingosine-1-phosphate (S1P) is a signaling molecule that regulates critical events including mammalian cell proliferation, survival, migration and cell-cell interactions. Most of these signals are triggered by engagement of sphingosine-1-phosphate receptors of the Edg family. However, accumulating evidence derived from investigation of non-mammalian models that lack Edg receptors suggests that sphingosine-1-phosphate-like molecules can act through alternative mechanisms and thereby contribute to morphogenesis, development, reproduction and survival. This review provides an overview of sphingosine-1-phosphate metabolism, the isolation of genes in this pathway employing yeast genetics, the evidence for its influence on non-mammalian development, and the pertinence of these findings to human disease. 相似文献
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Mudasir A. Mir Sheikh Mansoor M. Sugapriya Mohammed Nasser Alyemeni Leonard Wijaya Parvaiz Ahmad 《Saudi Journal of Biological Sciences》2021,28(2):1308-1317
The existence of genetic diversity in Crocus sativus has globally remained a mystery till date. The study investigated PCR based DNA amplification profile of saffron using ISSR and RAPD based primers. A total of 38 amplicons were generated by ISSR primers in the range from 7 to 12 with an average of 9.50 bands per primer. 20 bands were found to be polymorphic and 18 were monomorphic with an average percentage of polymorphism as 52.48%. RAPD based amplification revealed a total 161 amplicons, 107 as polymorphic and 54 as monomorphic with an average percentage of polymorphism as 66.44%. Cumulative results of RAPD and ISSR demonstrated that Nei-Li’s similarity index ranged between 0.70 and 0.97. The results of AMOVA has revealed 9% of variance among populations and 91% of variance within populations, Φ PT was found as 0.089, which indicates existence of genetic differences though limited. In conclusion, the results indicate that saffron accessions are minimally genetically differentiated, which could be capitalized in future breeding programmes to ameliorate this precious crop. 相似文献
1000.
Shahzad Z. Iqbal R. Russell M. Paterson Ijaz A. Bhatti Muhammad R. Asi Munir A. Sheikh Haq N. Bhatti 《Mycotoxin Research》2010,26(3):205-209
The occurrence of aflatoxin B1 (AFB1) in chilies from Pakistan was determined by using HPLC in work undertaken in Pakistan.
Whole (n = 22) and powdered (n = 22) chilies were analyzed. Sixteen (73.0%) and 19 (86.4%) samples of whole and ground chilies, respectively, were contaminated.
The mean concentration in powdered chilies (32.20 μg/kg) was higher statistically than in whole chilies (24.69 μg/kg). Concentrations
ranged from 0.00 to 89.56 μg/kg for powdered chilies, compared with 0.00–96.3 μg/kg for whole chilies. The limits of detection
and quantification were 0.05 μg/kg and 0.53 μg/kg, respectively. The concentrations were high in general and greater than
the statutory limit set by the European Union. There is considerable scope for improvements in chili production in Pakistan. 相似文献