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91.
Yen Yi Chou Te Yu Lin Jung Chung Lin Ning Chi Wang Ming Yieh Peng Feng Yee Chang 《Journal of microbiology, immunology, and infection》2008,41(2):124-129
BACKGROUND AND PURPOSE: Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens. This study was conducted to clarify the clinical features and outcome of patients with vancomycin-resistant enterococcal bacteremia. METHODS: Patients with vancomycin-resistant enterococcal bacteremia treated at a medical center in northern Taiwan between November 1998 and July 2006 were reviewed. Clinical and bacteriological characteristics of Enterococcus faecium and Enterococcus faecalis were compared. RESULTS: Twelve patients (6 males and 6 females) were included for analyses. The mean age was 69.3 years (range, 40 to 86 years), and 8 cases (66.7%) were older than 65 years. All patients had underlying disease. Two patients received total hip replacement before development of VRE bacteremia. Twelve patients had prior exposure to broad-spectrum antimicrobial therapy. Ten patients had prior intensive care unit stay and prior mechanical ventilation before VRE bacteremia. All of the patients (n = 12) had an intravascular catheter in place. Bacteremia was caused by E. faecalis in 4 patients and by E. faecium in eight. The portals of entry included urinary tract (8.3%), skin, soft tissue and bone (41.7%) and unknown sources (50.0%). E. faecium showed a higher rate of resistance to ampicillin and teicoplanin than E. faecalis (87.5% vs 0.0%, p=0.01). The 60-day mortality rate was higher in patients with E. faecium bacteremia than E. faecalis bacteremia (62.5% vs 0.0%), although statistical significance was not obtained (p=0.08). CONCLUSIONS: VRE bacteremia may have an impact on the mortality and morbidity of hospitalized patients. Patients with bacteremia caused by vancomycin-resistant E. faecium had a grave prognosis, especially immunosuppressed patients. The prudent use of antibiotics and strict enforcement of infection control may prevent further emergence and spread of VRE. 相似文献
92.
Zagzag D Salnikow K Chiriboga L Yee H Lan L Ali MA Garcia R Demaria S Newcomb EW 《Laboratory investigation; a journal of technical methods and pathology》2005,85(3):328-341
Invasion into surrounding brain tissue is a fundamental feature of gliomas and the major reason for treatment failure. The process of brain invasion in gliomas is not well understood. Differences in gene expression and/or gene products between invading and noninvading glioma cells may identify potential targets for new therapies. To look for genes associated with glioma invasion, we first employed Affymetrix microarray Genechip technology to identify genes differentially expressed in migrating glioma cells in vitro and in invading glioma cells in vivo using laser capture microdissection. We observed upregulation of a variety of genes, previously reported to be linked to glioma cell migration and invasion. Remarkably, major histocompatiblity complex (MHC) class I and II genes were significantly downregulated in migrating cells in vitro and in invading cells in vivo. Decreased MHC expression was confirmed in migrating glioma cells in vitro using RT-PCR and in invading glioma cells in vivo by immunohistochemical staining of human and murine glioblastomas for beta2 microglobulin, a marker of MHC class I protein expression. To the best of our knowledge, this report is the first to describe the downregulation of MHC class I and II antigens in migrating and invading glioma cells, in vitro and in vivo, respectively. These results suggest that the very process of tumor invasion is associated with decreased expression of MHC antigens allowing glioma cells to invade the surrounding brain in a 'stealth'-like manner. 相似文献
93.
Characterization of melanocyte stimulating hormone receptor variant alleles in twins with red hair 总被引:7,自引:3,他引:7
The association between MSHR coding region variation and hair colour in
humans has been examined by genotyping 25 red haired and 62 non-red
Caucasians, all of whom were 12 years of age and members of a twin pair
study. Twelve amino acid substitutions were seen at 11 different sites,
nine of these being newly described MSHR variants. The previously reported
Val92Met allele shows no association with hair colour, but the three
alleles Arg151Cys, Arg160Trp and Asp294His were associated with red hair
and one Val60Leu variant was most frequent in fair/blonde and light brown
hair colours. Variant MSHR genotypes are associated with lighter skin types
and red hair (P < 0.001). However, comparison of the MSHR genotypes in
dizygotic twin pairs discordant for red hair colour indicates that the MSHR
gene cannot be solely responsible for the red hair phenotype, since five of
13 pairs tested had both haplotypes identical by state (with three of the
five having both identical by descent). Rather, it is likely that
additional modifier genes exist, making variance in the MSHR gene necessary
but not always sufficient, for red hair production.
相似文献
94.
Mahadevaiah SK; Odorisio T; Elliott DJ; Rattigan A; Szot M; Laval SH; Washburn LL; McCarrey JR; Cattanach BM; Lovell-Badge R; Burgoyne PS 《Human molecular genetics》1998,7(4):715-727
An RNA-binding motif (RBM) gene family has been identified on the human Y
chromosome that maps to the same deletion interval as the 'azoospermia
factor' (AZF). We have identified the homologous gene family (Rbm) on the
mouse Y with a view to investigating the proposal that this gene family
plays a role in spermatogenesis. At least 25 and probably >50 copies of
Rbm are present on the mouse Y chromosome short arm located between Sry and
the centromere. As in the human, a role in spermatogenesis is indicated by
a germ cell-specific pattern of expression in the testis, but there are
distinct differences in the pattern of expression between the two species.
Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are
female due to a position effect resulting in non-expression of Sry ;
sex-reversing such mice with an Sry transgene produces males with a high
incidence of abnormal sperm, making this the third deletion interval on the
mouse Y that affects some aspect of spermatogenesis. Most of the copies of
Rbm map to this deletion interval, and the Yd1males have markedly reduced
Rbm expression, suggesting that RBM deficiency may be responsible for, or
contribute to, the abnormal sperm development. In man, deletion of the
functional copies of RBM is associated with meiotic arrest rather than
sperm anomalies; however, the different effects of deletion are consistent
with the differences in expression between the two species.
相似文献
95.
Vaughan JR; Farrer MJ; Wszolek ZK; Gasser T; Durr A; Agid Y; Bonifati V; DeMichele G; Volpe G; Lincoln S; Breteler M; Meco G; Brice A; Marsden CD; Hardy J; Wood NW 《Human molecular genetics》1998,7(4):751-753
A mutation in exon 4 of the human alpha-synuclein gene was reported
recently in four families with autosomal dominant Parkinson's disease (PD).
In order to examine whether mutations in this exon or elsewhere in the gene
are common in familial PD, all seven exons of the alpha- synuclein gene
were amplified by PCR from index cases of 30 European and American
Caucasian kindreds affected with autosomal dominant PD. Each product was
sequenced directly and examined for mutations in the open reading frame. No
mutations were found in any of the samples examined. We conclude that the
A53T change described in the alpha- synuclein gene is a rare cause of PD or
may even be a rare variant. Mutations in the regulatory or intronic regions
of the gene were not excluded by this study.
相似文献
96.
A male infant is described in whom congenital anomalies were recognized prenatally by ultrasound examination. The infant was delivered following spontaneous labor and died approximately 15 min after birth. An autopsy revealed major anomalies in the central nervous system (holoprosencephaly with premaxillary agenesis), the gastrointestinal system (esophageal atresia) and the heart (tetralogy of Fallot). Chromosomal studies revealed recombinant chromosome 5 [46,XY, rec(5), dup q, inv(5)(p15q32)], resulting in partial trisomy 5q and partial monosomy 5p. Cytogenetic investigation of the family revealed a pericentric inversion of chromosome 5 in the father and paternal grandmother, 46,XY (and XX, respectively,) inv(5)(p15q32). The congenital anomalies in this infant are more extensive and severe than previously reported in cases of recombination aneusomy involving chromosome 5. 相似文献
97.
PCR-based detection of Bacillus anthracis in formalin-fixed tissue from a patient receiving ciprofloxacin 总被引:3,自引:0,他引:3
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Levine SM Perez-Perez G Olivares A Yee H Hanna BA Blaser MJ 《Journal of clinical microbiology》2002,40(11):4360-4362
We demonstrate that Bacillus anthracis may be detected from a formalin-fixed, paraffin-embedded biopsy specimen, even after the patient has received antibiotic treatment. Although traditional PCR methods may not be sufficiently sensitive for anthrax detection in such patients, cycle numbers can be increased or PCR can be repeated by using an aliquot from a previous PCR as the template. 相似文献
98.
99.
The DNA of the human serum amyloid A (SAA) gene GSAA1 contains several repetitive regions within its introns. We have studied length variations at one such region in the 2nd intron by selective amplification using the polymerase chain reaction (PCR) and defined oligonucleotide primers. The lengths of the repetitive regions frequently differ between individual chromosomes and can be transmitted as Mendelian markers, making them useful for genetic linkage analysis. 相似文献
100.
SARS病毒S1蛋白重组C端片段免疫效果的实验研究 总被引:1,自引:0,他引:1
为获得纯化的重组SARS病毒S1蛋白C端 ,研究其刺激机体产生针对SARS病毒免疫应答的规律和机制 ,将编码SARS病毒S1蛋白C端 311个氨基酸残基的基因克隆 ,并在原核表达系统中表达 ,纯化获得了的重组蛋白。利用SARS患者恢复期的血清 ,对纯化的重组S1蛋白进行血清学分析。结果表明 ,本研究中克隆表达的重组蛋白序列与公布的SARS病毒S1蛋白C端的序列相同 ,其编码的重组蛋白相对分子质量约为 5 90 0 0Mr。SARS患者恢复期的血清均与重组蛋白反应 ,在5 9 0 0 0Mr处形成特异性的反应条带 ,而来自SARS流行前的正常人对照血清则不能与重组蛋白反应。在本研究中获得的重组蛋白可以为研究SARS病毒识别宿主细胞受体的过程及其机制提供条件。 相似文献