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91.
Over-expression of fibroblast growth factor 8 (FGF8) in human prostate cancer is associated with clinically aggressive disease. Among different members of the FGF family, FGF17 and FGF8 share high sequence homology and have similar patterns of expression during embryogenesis. In this study, the clinical significance of FGF17 expression and its in vitro function in prostate cancer cells were tested. Forty resected prostate specimens from patients with benign prostatic hyperplasia (BPH, n = 12) and prostate cancer (CaP, n = 28; Gleason sum scores 3-10) were studied using semi-quantitative RT-PCR. In addition, 85 cases of CaP (Gleason sum scores 5-9) and 20 cases of BPH were examined using immunohistochemistry and findings were correlated with clinical parameters. In vitro experiments using prostate cancer cell lines examined the functional significance of FGF17 in prostate cancer. These studies revealed a significant linear correlation between increasing Gleason sum scores and FGF17 expression using both immunohistochemistry (p < 0.0001, rho = 0.99) and RT-PCR (p = 0.008, rho = 0.99). Immunohistochemistry demonstrated upregulation of FGF17 in CaP compared with BPH (p < 0.0001) and, when comparing high-grade CaP (Gleason sum score 7-10) with BPH, RT-PCR showed a fourfold upregulation of FGF17 mRNA expression (p < 0.0001). Men with tumours displaying high levels of FGF17 expression had a worse outcome on survival analysis (p = 0.044) and a higher risk of progression with metastases (p < 0.0001). Proliferation assays showed low-dose recombinant (r) FGF17 (1 ng/ml) to be a more potent mitogen than rFGF1 and rFGF8 in prostate cancer cell lines (LNCaP, DU145, and PC3M) (p < 0.001). Furthermore, FGF8 was shown to induce expression of FGF17 in these cell lines. These data support a role for FGF17, and a model of co-expression of multiple FGFs, with FGF17 as a potential mediator of FGF8 function, in human prostate carcinogenesis.  相似文献   
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In order to evaluate the efficacy of convalescent plasma therapy in the treatment of patients with severe acute respiratory syndrome (SARS), 80 SARS patients were given convalescent plasma at Prince of Wales Hospital, Hong Kong, between 20 March and 26 May 2003. Good outcome was defined as discharge by day 22 following the onset of SARS symptoms. Poor outcome was defined as death or hospitalization beyond 22 days. A higher day-22 discharge rate was observed among patients who were given convalescent plasma before day 14 of illness (58.3% vs 15.6%; P<0.001) and among those who were PCR positive and seronegative for coronavirus at the time of plasma infusion (66.7% vs 20%; P=0.001).  相似文献   
94.
Biochemical and biological properties of Staphylococcal enterotoxin K   总被引:21,自引:0,他引:21       下载免费PDF全文
Staphylococcus aureus is an important human pathogen which is implicated in a wide variety of diseases. Major determinants of the virulence of this organism include extracellular virulence factors. Staphylococcal enterotoxins (SEs) are important causative agents in staphylococcal toxic shock syndrome and food poisoning. Our study identified a novel enterotoxin, SEK, and examined its biochemical and biological properties. SEK had a molecular weight of 26,000 and an experimentally determined pI of between 7.0 and 7.5. SEK was secreted by clinical isolates of S. aureus. We demonstrated that SEK had many of the biological activities associated with the SEs, including superantigenicity, pyrogenicity, the ability to enhance the lethal effect of endotoxin, and lethality in a rabbit model when administered by subcutaneous miniosmotic pump. Recombinant SEK was shown to stimulate human CD4(+) and CD8(+) T cells in a Vbeta-specific manner; T-cells bearing Vbeta 5.1, 5.2, and 6.7 were significantly stimulated to proliferate.  相似文献   
95.
A major barrier to conceptual advances in understanding the mechanisms and regulation of imprinting of a genomic region is our relatively poor understanding of the overall organization of genes and of the potentially important cis-acting regulatory sequences that lie in the nonexonic segments that make up 97% of the genome. Interspecies sequence comparison offers an effective approach to identify sequence from conserved functional elements. In this article we describe the successful use of this approach in comparing a approximately 1-Mb imprinted genomic domain on mouse chromosome 7 to its orthologous region on human 11p15.5. Within the region, we identified 112 exons of known genes as well as a novel gene identified uniquely in the mouse region, termed Msuit, that was found to be imprinted. In addition to these coding elements, we identified 33 CpG islands and 49 orthologous nonexonic, nonisland sequences that met our criteria as being conserved, and making up 4.1% of the total sequence. These conserved noncoding sequence elements were generally clustered near imprinted genes and the majority were between Igf2 and H19 or within Kvlqt1. Finally, the location of CpG islands provided evidence that suggested a two-island rule for imprinted genes. This study provides the first global view of the architecture of an entire imprinted domain and provides candidate sequence elements for subsequent functional analyses.  相似文献   
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Neopterin and C-reactive protein (CRP) concentrations were determined in serum samples from 129 severe acute respiratory syndrome (SARS) patients and 156 healthy blood donors. In the patients with confirmed SARS, an early neopterin elevation was detected already at the day of onset of symptoms and rose to a maximum level of 45.0 nmol/L 3 days after the onset. All SARS patients had elevated neopterin concentrations (>10 nmol/L) within 9 days after the onset. The mean neopterin concentrations were 34.2 nmol/L in acute sera of SARS patients, 5.1 nmol/L in convalescent sera, and 6.7 nmol/L in healthy controls. In contrast, the mean CRP concentrations in both acute and convalescent sera of SARS patients were in the normal range (<10 mg/L). Serum neopterin level in SARS patients was associated with fever period and thus the clinical progression of the disease, while there was no significant correlation between the CRP level and the fever period. Serum neopterin may allow early assessment of the severity of SARS. The decrease of neopterin level was found after steroid treatment, which indicates that blood samples should be collected before steroid treatment for the neopterin measurement.  相似文献   
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