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排序方式: 共有1767条查询结果,搜索用时 15 毫秒
61.
Sandesh Chakravarthy Sreenath Nagamani Ayelet Erez Joseph Shen Chumei Li Elizabeth Roeder Sarah Cox Lefkothea Karaviti Margret Pearson Sung-Hae L Kang Trilochan Sahoo Seema R Lalani Pawel Stankiewicz V Reid Sutton Sau Wai Cheung 《European journal of human genetics : EJHG》2010,18(3):278-284
Deletions in chromosome 17q12 encompassing the HNF1β gene cause cystic renal disease and maturity onset diabetes of the young, and have been recently described as the first recurrent genomic deletion leading to diabetes. Earlier reports of patients with this microdeletion syndrome have suggested an absence of cognitive impairment, differentiating it from most other contiguous gene deletion syndromes. The reciprocal duplication of 17q12 is rare and has been hypothesized to be associated with an increased risk of epilepsy and mental retardation. We conducted a detailed clinical and molecular characterization of four patients with a deletion and five patients with a reciprocal duplication of this region. Our patients with deletion of 17q12 presented with cognitive impairment, cystic renal disease, seizures, and structural abnormalities of the brain. Patients with reciprocal duplications manifest with cognitive impairment and behavioral abnormalities, but not with seizures. Our findings expand the phenotypic spectrum associated with rearrangements of 17q12 and show that cognitive impairment is a part of the phenotype of individuals with deletions of 17q12. 相似文献
62.
Zhang W Qi W Albert TJ Motiwala AS Alland D Hyytia-Trees EK Ribot EM Fields PI Whittam TS Swaminathan B 《Genome research》2006,16(6):757-767
Infections by Shiga toxin-producing Escherichia coli O157:H7 (STEC O157) are the predominant cause of bloody diarrhea and hemolytic uremic syndrome in the United States. In silico comparison of the two complete STEC O157 genomes (Sakai and EDL933) revealed a strikingly high level of sequence identity in orthologous protein-coding genes, limiting the use of nucleotide sequences to study the evolution and epidemiology of this bacterial pathogen. To systematically examine single nucleotide polymorphisms (SNPs) at a genome scale, we designed comparative genome sequencing microarrays and analyzed 1199 chromosomal genes (a total of 1,167,948 bp) and 92,721 bp of the large virulence plasmid (pO157) of eleven outbreak-associated STEC O157 strains. We discovered 906 SNPs in 523 chromosomal genes and observed a high level of DNA polymorphisms among the pO157 plasmids. Based on a uniform rate of synonymous substitution for Escherichia coli and Salmonella enterica (4.7x10(-9) per site per year), we estimate that the most recent common ancestor of the contemporary beta-glucuronidase-negative, non-sorbitolfermenting STEC O157 strains existed ca. 40 thousand years ago. The phylogeny of the STEC O157 strains based on the informative synonymous SNPs was compared to the maximum parsimony trees inferred from pulsed-field gel electrophoresis and multilocus variable numbers of tandem repeats analysis. The topological discrepancies indicate that, in contrast to the synonymous mutations, parts of STEC O157 genomes have evolved through different mechanisms with highly variable divergence rates. The SNP loci reported here will provide useful genetic markers for developing high-throughput methods for fine-resolution genotyping of STEC O157. Functional characterization of nucleotide polymorphisms should shed new insights on the evolution, epidemiology, and pathogenesis of STEC O157 and related pathogens. 相似文献
63.
S. M. Gupta M. Bala S. Muralidhar K. Ray 《European journal of clinical microbiology & infectious diseases》2009,28(5):461-468
Test results of syphilis serology are critical due to inter- and intralaboratory variability. The accuracy of results is crucial
in the control of the disease. This study was aimed to compare results of laboratories and performance of methods for syphilis
serology. Results of Veneral Disease Reference Laboratory (VDRL) or rapid plasma reagin (RPR) tests of 25 microbiology laboratories
were compared in six proficiency testing sentinel surveys. The performance of laboratories was compared with the results of
a hypothetical average laboratory. Of the 141 participants, 104 (73.8%) responded. The inter-laboratory variability was exhibited
by 62.2% of samples tested by VDRL and 58.7% by RPR test. Intralaboratory variability was observed in 46.7% samples. There
was an insignificant improvement in proficiency testing (PT) performance over the years with a significant improvement in
2007. The common errors involved departure from testing protocols. Syphilis serology proficiency testing is needed in India
for reliability in test results. 相似文献
64.
Davey AL Foxton SJ Bala P Richards M Cuthbert A 《Journal of paediatrics and child health》2007,43(4):310-311
Bruising is a presentation that often causes concern. There are many causes of bruising in children, including non-accidental injury, which must be excluded. We report a case of a 22-month-old boy where all the common diagnoses were excluded. We highlight the need to be aware of transient acquired inhibitors of coagulation that can cause spontaneous bleeding. 相似文献
65.
Bala L Tripathi P Bhatt G Das K Roy R Choudhuri G Khetrapal CL 《NMR in biomedicine》2009,22(2):220-228
Patients with extrahepatic biliary obstruction present with impairment of the normal bile flow, with jaundice and cholangitis as common complications. (1)H and (31)P NMR quantitative analysis of bile specimens from patients with extrahepatic biliary obstruction (n = 80) (with/without jaundice and cholangitis separately and together) was carried out for the chief biliary constituents to determine the relationship between biliary constituents and jaundice (serum bilirubin concentration >or=1.0 mg/dL) and cholangitis (total leucocyte count >11,000 cells/mm(3) and/or fever >38.5 degrees C with/without bile culture positivity). Compared with controls (patients without jaundice and cholangitis), median indices of the chief biliary constituents (total bile acids, cholesterol, phosphatidylcholine and inorganic phosphate) were significantly suppressed in patients with cholangitis and/or jaundice. Quantities of total bile acids, cholesterol and phosphatidylcholine correlated negatively with the quantity of bilirubin and with cholangitis, i.e. total leucocyte count. Suppression of biliary constituents correlated significantly with the severity of jaundice and cholangitis. The decrease in biliary constituents in the presence of jaundice and cholangitis is possibly the result of downregulation of the function of transporters located at the canalicular side of hepatocytes, leading to their suppressed indices in bile. This information may have implications in the examination of bile for clinical studies. 相似文献
66.
Rao S Sen R Singh S Ghalaut PS Arora BB 《Indian journal of pathology & microbiology》2005,48(3):341-344
In the course of Chronic myeloid leukemia (CML), appearance of increased number of blasts may herald evolution of accelerated phase as well as onset of marrow fibrosis (MF) thereby necessitating the need to perform trephine biopsy for correct diagnosis and appropriate treatment. In the existing grading systems of MF, a comprehensive view has not been taken of the variability of density and area occupied by reticulin and collagen fibres. To overcome this shortcoming, we quantitated the reticulin and collagen content of marrow, its pattern of distribution and percentage area occupied by each type of fibres in every individual case. We performed 50 bone marrow (BM) trephine biopsies in patients of CML in order to assess the incidence and degree of MF. Various grades of MF were correlated with peripheral smear including blast count, bone marrow aspirate and LAP score of the case. A positive correlation was found between increasing grades of MF and number of megakaryocytes in the BM. 相似文献
67.
68.
69.
S Bala Y Tilahun O Taha H Alao K Kodys D Catalano G Szabo 《Journal of translational medicine》2012,10(1):151
ABSTRACT: BACKGROUND: Hepatitis C Virus (HCV), a single stranded RNA virus, affects millions of people worldwide and leads to chronic infection characterized by chronic inflammation in the liver and in peripheral immune cells. Chronic liver inflammation leads to progressive liver damage. MicroRNAs (miRNA) regulate inflammation (miR-155, -146a and -125b) as well as hepatocyte function (miR-122). METHODS: Here we hypothesized that microRNAs are dysregulated in chronic HCV infection. We examined miRNAs in the circulation and in peripheral monocytes of patients with chronic HCV infection to evaluate if specific miRNA expression correlated with HCV infection. RESULTS: We found that monocytes from chronic HCV infected treatment-naive (cHCV) but not treatment responder patients showed increased expression of miR-155, a positive regulator of TNFalpha, and had increased TNFalpha production compared to monocytes of normal controls. After LPS stimulation, miR-155 levels were higher in monocytes from cHCV patients compared to controls. MiR-125b, which has negative regulatory effects on inflammation, was decreased in cHCV monocytes compared to controls. Stimulation of normal monocytes with TLR4 and TLR8 ligands or HCV core, NS3 and NS5 recombinant proteins induced a robust increase in both miR-155 expression and TNFalpha production identifying potential mechanisms for in vivo induction of miR-155. Furthermore, we found increased serum miR-155 levels in HCV patients compared to controls. Serum miR-125b and miR-146a levels were also increased in HCV patients. Serum levels of miR-122 were elevated in cHCV patients and correlated with increased ALT and AST levels and serum miR-155 levels. CONCLUSION: In conclusion, our novel data demonstrate that miR-155, a positive regulator of inflammation, is upregulated both in monocytes and in the serum of patients with chronic HCV infection. Our study suggests that HCV core, NS3, and NS5 proteins or TLR4 and TLR8 ligands can mediate increased miR-155 and TNFalpha production in chronic HCV infection. The positive correlation between serum miR-155 and miR-122 increase in cHCV may be an indicator of inflammation-induced hepatocyte damage. 相似文献
70.
Devinder K.A. Singh Bala S. Rajaratnam Vijayakumar Palaniswamy Hannah Pearson Vimal P. Raman Pei Sien Bong 《Maturitas》2012