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101.
Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis.  相似文献   
102.

Objective

To describe the perspectives and experiences of athletic trainers, coaches, and student-athletes approximately three years post-implementation of the NCAA sickle cell trait (SCT) screening policy.

Participants

Two-hundred and eight student-athletes, 32 athletic trainers, and 43 coaches from 10 NCAA Division I (DI) institutions in North Carolina from January to June 2014.

Methods

Two online surveys were used to assess knowledge, perspectives, and experiences.

Results

Athletic staff were more supportive than student-athletes of the need for the policy. Noted challenges included variation in implementation and follow-up for SCT-positive athletes, financial costs to institutions and athletes, and timing of the screening.

Conclusions

More education about SCT is needed for student-athletes and athletic staff in order to help make the implementation more successful. All parties need to be in agreement regarding the importance of knowing which student-athletes have SCT and how that information will be utilized.  相似文献   
103.
104.
105.
Oocyte morphology predicts outcome of intracytoplasmic sperm injection   总被引:10,自引:14,他引:10  
To examine the influence of cytoplasmic morphology on the success rate of intracytoplasmic sperm injection (ICSI), the morphology of 837 metaphase II oocytes was assessed after cumulus stripping. The main abnormalities detected were excessive granularity, cytoplasmic inclusions such as vacuoles, smooth endoplasmic reticulum clustering and refractile bodies. Microinjection was performed in 538 oocytes with normal cytoplasm, 142 out of 161 with excessive granularity and 112 out of 138 with cytoplasmic inclusions. Very poor oocytes were not injected. No difference was found in fertilization rate. The embryos achieved cleaved normally and a similar number of good quality embryos among the three groups was noted. The outcome of transfer of embryos derived solely from normal oocytes (group A: 72 patients, 183 embryos) was compared with those from oocytes with cytoplasmic abnormalities (group B: 34 patients, 85 embryos). In group A, 17 clinical pregnancies (24% per patient, implantation rate 10%) were established. In group B, only one clinical pregnancy (3% per patient, implantation rate 1%) was established, from the transfer of embryos derived from oocytes with homogeneous granularity of the cytoplasm. No pregnancy resulted following the transfer of embryos from eggs with cytoplasmic inclusions. The difference was statistically significant. The outcome of ICSI is dependent on the quality of the oocytes retrieved. Normal fertilization and early embryo development were achieved in oocytes with abnormal cytoplasm morphology, but the resulting embryos failed to demonstrate the same implantation potential as those derived from oocytes with normal cytoplasm.   相似文献   
106.
Using mechanical and chemical dissection methods, fibrous sheath was isolated both from normal ejaculated human spermatozoa and from rabbit cauda epididymal spermatozoa. The same techniques did not produce a pure preparation of fibrous sheath from ejaculated rabbit spermatozoa, suggesting that further cross-linking and stabilization of sperm structures occurs in response to components of the seminal plasma. The isolation procedures were monitored by phase contrast microscopy and the purity of the fibrous sheath was verified by electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human fibrous sheath revealed at least 14 protein bands of which the most intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5 kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid composition of the purified fibrous sheath from human and rabbit spermatozoa was similar, being high in aspartic acid and/or asparagine and glutamic acid and/or glutamine, serine, alanine, leucine, lysine and glycine, but low in histidine, tyrosine and isoleucine. This composition is similar to that reported for the rat and suggests that mammalian sperm tail fibrous sheaths are composed of similar types of proteins, although there are apparent differences in protein components between species.   相似文献   
107.
108.
Baird  DM; Royle  NJ 《Human molecular genetics》1997,6(13):2291-2299
A high level of sequence polymorphism combined with linkage disequilibrium has created a limited number of highly diverged haplotypes across the human Xp/Yp telomere junction region. To gain insight into the unusual genetic characteristics of this region, we have examined the orthologous sequences in the common chimpanzee (Pan troglodytes ), the gorilla (Gorilla gorilla) and the orang-utan (Pongo pygmaeus). Divergence from the human Xp/Yp sequence is higher (average 2.6-fold) than that observed at other loci. The position of the human Xp/Yp telomere is unique, as additional sequences are present at this location in the other three species. These included an array of subterminal satellite in the chimpanzee and, in the gorilla a small interstitial array of telomere-like repeats followed by sequences with strong homology to the human 18p subterminal region. In the orang-utan, two alleles with different structures were identified. These differ by the presence or absence of a short interspersed nuclear element (SINE) sequence just proximal to long arrays of telomere-like repeat sequences that probably represent the proximal end of the orang-utan Xp/Yp telomere. In addition, a high level of sequence divergence between the two orang-utan structures was identified. This divergence is similar to that observed between the human Xp/Yp telomere-adjacent haplotypes. The high sequence divergence and evidence of gross rearrangements indicate that the Xp/Yp telomeric region has evolved faster than the rest of the genome.   相似文献   
109.
As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.   相似文献   
110.
Malignant peripheral nerve sheath tumours (MPNSTs) are aggressive soft tissue tumours that occur either sporadically or in patients with neurofibromatosis type 1. The malignant transformation of the benign neurofibroma to MPNST is incompletely understood at the molecular level. We have determined the gene expression signature for benign and malignant PNSTs and found that the major trend in malignant transformation from neurofibroma to MPNST consists of the loss of expression of a large number of genes, rather than widespread increase in gene expression. Relatively few genes are expressed at higher levels in MPNSTs and these include genes involved in cell proliferation and genes implicated in tumour metastasis. In addition, a gene expression signature indicating p53 inactivation is seen in the majority of MPNSTs. Subsequent microRNA profiling of benign and malignant PNSTs indicated a relative down‐regulation of miR‐34a in most MPNSTs compared to neurofibromas. In vitro studies using the cell lines MPNST‐14 (NF1 mutant) and MPNST‐724 (from a non‐NF1 individual) show that exogenous expression of p53 or miR‐34a promotes apoptotic cell death. In addition, exogenous expression of p53 in MPNST cells induces miR‐34a and other miRNAs. Our data show that p53 inactivation and subsequent loss of expression of miR‐34a may significantly contribute to the MPNST development. Collectively, our findings suggest that deregulation of miRNAs has a potential role in the malignant transformation process in peripheral nerve sheath tumours. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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