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61.
Young Kun Lee Sung Yeon Hwang Tae Gun Shin Ik Joon Jo Gee Young Suh Kyeongman Jeon 《PloS one》2016,11(4)
The objective of this study was to evaluate the prognostic value of static and dynamic variables of central venous oxygen saturation (ScvO2) and lactate in patients with severe sepsis or septic shock who underwent early quantitative resuscitation. We also investigated whether ScvO2 measured after initial resuscitation could provide additive prognostic value to that of lactate. We analyzed the sepsis registry for patients presenting to the emergency department and included patients with simultaneous measurements of lactate and ScvO2 at the time of presentation (H0) and 6 hours (H6) after resuscitation. The primary outcome was 28-day mortality and multivariable logistic analysis was used to adjust for confounders. A total of 363 patients were included, and the overall 28-day mortality was 18%. The area under the receiver operator characteristic curve for predicting 28-day mortality was as follows: lactate (H6), 0.81; lactate (H0), 0.73; relative lactate change, 0.67; ScvO2 (H6), 0.65; relative ScvO2 change 0.59; ScvO2 (H0), 0.58. Patients with lactate normalization showed significantly lower 28-day mortality compared to patients without lactate normalization (3% vs. 28%, P<0.01). However, in those who achieved ScvO2 (H6) ≥70%, there was a significant difference in 28-mortality only in patients without lactate normalization (21% vs. 39%, P<0.01) but no difference in those with lactate normalization (4% vs. 3%, P = 0.71). In multivariable analysis, lactate normalization was significantly associated with 28-day mortality (adjusted odds ratio [OR] for 28-day mortality, 0.20; 95% confidence interval [CI], 0.07–0.54; P <0.01), but ScvO2 (H6) ≥70% showed only a marginal association (the adjusted OR for 28-day mortality, 0.51; 95% CI, 0.26–1.01; P = 0.05). ScvO2 (H6) ≥70% was associated with 28-day mortality only in cases without lactate normalization in subgroup analysis (adjusted OR 0.37, 95% CI, 0.18–0.79; P = 0.01). Six-hour lactate was the strongest predictor of 28-day mortality in patients with severe sepsis or septic shock. Six-hour ScvO2 provided additional prognostic value only in cases where lactate values were not normalized after resuscitation. 相似文献
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Upon epidermal growth factor treatment, phospholipase C-gamma1 (PLC-gamma1) translocates from cytosol to membrane where it is phosphorylated at tyrosine residues. Caveolae are small plasma membrane invaginations whose structural protein is caveolin. In this study, we show that the translocation of PLC-gamma1 and its tyrosine phosphorylation are localized in caveolae by caveolin-enriched low-density membrane (CM) preparation and immunostaining of cells. Pretreatment of cells with methyl-beta-cyclodextrin (MbetaCD), a chemical disrupting caveolae structure, inhibits the translocation of PLC-gamma1 to CM as well as phosphatidylinositol (PtdIns) turnover. However, MbetaCD shows no effect on tyrosine phosphorylation level of PLC-gamma1. Our findings suggest that, for proper signaling, PLC-gamma1 phosphorylation has to occur at PtdInsP(2)-enriched sites. 相似文献
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ABSTRACT: BACKGROUND: Almost half of the Caenorhabditis elegans genome encodes proteins with either a signal peptide or a transmembrane domain. Therefore a substantial fraction of the proteins are localized to membranes, reside in the secretory pathway or are secreted. While these proteins are of interest to a variety of different researchers ranging from developmental biologists to immunologists, most of secreted proteins have not been functionally characterized so far. RESULTS: We grouped proteins containing a signal peptide or a transmembrane domain using various criteria including evolutionary origin, common domain organization and functional categories. We found that putative secreted proteins are enriched for small proteins and nematode-specific proteins. Many secreted proteins are predominantly expressed in specific life stages or in one of the two sexes suggesting stage- or sex-specific functions. More than a third of the putative secreted proteins are upregulated upon exposure to pathogens, indicating that a substantial fraction may have a role in immune response. Slightly more than half of the transmembrane proteins can be grouped into broad functional categories based on sequence similarity to proteins with known function. By far the largest groups are channels and transporters, various classes of enzymes and putative receptors with signaling function. CONCLUSION: Our analysis provides an overview of all putative secreted and transmembrane proteins in C. elegans. This can serve as a basis for selecting groups of proteins for large-scale functional analysis using reverse genetic approaches. 相似文献
65.
YR Kim JS Kim YH Min DH Yoon HJ Shin YC Mun Y Park YR Do SH Jeong JS Park SY Oh S Lee EK Park JS Jang WS Lee HW Lee H Eom JS Ahn J Jeong SK Baek SJ Kim WS Kim C Suh 《Journal of hematology & oncology》2012,5(1):49
ABSTRACT: BACKGROUND: The objective of this study was to identify prognostic factors for survival in patients with primary diffuse large B-cell lymphoma (DLBCL) of the adrenal gland. METHODS: Thirty one patients diagnosed with primary adrenal DLBCL from 14 Korean institutions and treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone) were analyzed. RESULTS: Complete remission (CR) and overall response rate after R-CHOP chemotherapy were 54.8% and 87.0%. The 2-year estimates of overall survival (OS) and progression-free survival (PFS) were 68.3% and 51.1%. In patients achieving CR, significant prolongations of OS (P = 0.029) and PFS (P = 0.005) were observed. Ann Arbor stage had no influence on OS. There was no significant difference in OS between patients with unilateral involvement of adrenal gland and those with bilateral involvement. When staging was modified to include bilateral adrenal involvement as one extranodal site, early stage (I or II) significantly correlated with longer OS (P = 0.021) and PFS (P <0.001). CONCLUSIONS: Contrary to prior reports, our data suggests that outcomes of primary adrenal DLBCL are encouraging using a regimen of R-CHOP, and that achieving CR after R-CHOP is predictive of survival. Likewise, our modified staging system may have prognostic value. 相似文献
66.
Park JH Nam Y Park SY Kim JK Choe NH Lee JY Oh YS Suh JG 《Journal of biochemical and molecular toxicology》2011,25(4):238-243
High glucose levels induce cell death in many cell types, including pancreatic β-cells. Although protective agents against glucotoxicity have been searched for extensively, so far none have been found. In this report, we tested silk fibroin (SF) as a candidate material for antiglucotoxicity in the pancreatic β-cell (HIT-T15 cell) line. Approximately 50% of cells were killed after treatment with 80 mg/mL glucose. This reduction of cell number was recovered by the addition of SF at 50 mg/mL. SF treatment also decreased cellular reactive oxygen species (ROS) and increased proliferating cellular nuclear antigen (PCNA) immunoreactivity. In addition, TUNEL assays demonstrated that SF protects against glucose-induced apoptosis of HIT-T15 cells, suggesting that SF might protect cells from cell death by lowering cellular ROS levels. SF also induced expression of the insulin-like growth factor-1 (IGF-1) gene, and IGF-1 expression may be the cause of SF-induced protection against glucose toxicity. Taken together, these results suggest that SF could serve as a potential therapeutic agent to treat the hyperglycemia-induced death of pancreatic β-cells. 相似文献
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Tuberculosis (TB) is a serious and potentially fatal disease caused by Mycobacterium tuberculosis (M. tb). The occurrence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) M. tb is a significant public health concern because most of the anti-TB drugs that have been in use for over 40 years are no longer effective for the treatment of these infections. Recently, new anti-TB lead compounds such as cyclomarin A, lassomycin, and ecumicin, which are cyclic peptides from actinomycetes, have shown potent anti-TB activity against MDR and XDR M. tb as well as drug-susceptible M. tb in vitro. The target molecule of these antibiotics is ClpC1, a protein that is essential for the growth of M. tb. In this review, we introduce the three anti-TB lead compounds as potential anti-TB therapeutic agents targeting ClpC1 and compare them with the existing anti-TB drugs approved by the US Food and Drug Administration. 相似文献
70.
Lee HW Suh JH Kim AY Lee YS Park SY Kim JB 《Molecular endocrinology (Baltimore, Md.)》2006,20(10):2432-2443
Osteogenesis is a complex process associated with dramatic changes in gene expression. To elucidate whether modifications in chromatin structure are involved in osteoblast differentiation, we examined the expression levels of histone deacetylases (HDACs) and the degree of histone acetylation at the promoter regions of osteogenic genes. During osteogenesis, total HDAC enzymatic activity was decreased with significant reduction in HDAC1 expression. Consistently, recruitment of HDAC1 to the promoters of osteoblast marker genes, including osterix and osteocalcin, was down-regulated, whereas histone H3 and H4 were hyperacetylated at those promoters during osteoblast differentiation. Moreover, suppression of HDAC activity with a HDAC inhibitor, sodium butyrate, accelerated osteogenesis by inducing osteoblast marker genes including osteopontin and alkaline phosphatase. Consistently, knockdown of HDAC1 by the short interference RNA system stimulated osteoblast differentiation. Taken together, these data propose that down-regulation of HDAC1 is an important process for osteogenesis. 相似文献