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91.
92.
alpha-Fetoprotein (AFP) is often elevated in hepatocellular carcinoma (HCC). This study was to elucidate the significance and related factors of AFP elevation in HCC in 781 unifocal HCCs receiving curative hepatectomy. We showed that high AFP (> 200 ng/ml), which was associated with AFP mRNA expression in HCC (p = 0.00001), correlated with major clinicopathologic factors. Younger age (< or = 55 years; p=0.00001), hepatitis B surface antigen (HBsAg) in serum (p=0.00001), p53 mutation (p=0.008), large tumor (p=0.00001), vascular invasion (p=0.00001) and early tumor recurrence (p=0.00001) were significant associates of high AFP, while anti-HCV in serum and beta-catenin mutation in HCC had less frequent high AFP (p=0.013 and < 0.0001, respectively). We also showed that HCC with high AFP had a lower 10-year survival (p < 0.0001), particularly in large HCC (p < 0.0001). At univariate analysis, high AFP (p < 0.0001), HBsAg positivity (p=0.05), p53 mutation (p=0.0004), liver cirrhosis (p=0.0094), large tumor (p=0.0003), vascular invasion (p < 0.0001) and early recurrence (p < 0.0001) were significant unfavorable prognostic factors. In Cox proportional hazards regression analysis, high AFP remained a borderline significance (OR=1.2; CI=1.0-1.4) after adjustment for the effect of tumor size and tumor stage (p=0.0821). Furthermore, the detection of AFP mRNA in the liver of AFP mRNA-positive HCC was associated with more frequent early recurrence (p=0.0026) and might be a useful marker of intrahepatic spread. We therefore conclude that AFP elevation, more than a coincidental epiphenomenon, appears to contribute to vascular invasion and HCC progression and help to identify subsets of HCC patients with increased risk for early recurrence and poor prognosis after hepatectomy.  相似文献   
93.
Gossypol has wide antineoplastic effects in vitro, but its effects on human lung cancer have not been explored. To evaluate the activity of gossypol against alveolar cell lung cancer and to provide information on the mechanism of action, we examined the effects of gossypol on the proliferation of A549 cells indirectly using an XTT assay and on the distribution of cells within the phases of the cell cycle using flow cytometry. We also examined several factors that may affect apoptosis, including p53, p21/WAF1, Fas receptor, Fas ligand (FasL) and caspase 8 activity. The results showed that gossypol inhibited proliferation of A549 cells at a concentration of 0.5 micromol/L after 12 h treatment. The effect was both dose- and time-dependent by the induction of apoptosis without the effect of p53 and p21/WAF1. Upregulation of Fas/FasL, in association with the activation of downstream caspase 8 activity, was observed following treatment with gossypol. The Fas/FasL pathway accounted for 75% of gossypol-mediated apoptosis. We suggest that the Fas/FasL apoptotic system is the major pathway for gossypol-mediated apoptosis of A549 cells. Gossypol had no effect on the distribution of A549 cells within the phases of the cell cycle. In conclusion, gossypol inhibited A549 cells mainly by induction of the Fas/FasL apoptotic pathway, but not the p53 and p21/WAF1 pathway.  相似文献   
94.
Hsu YL  Kuo PL  Liu CF  Lin CC 《Cancer letters》2004,212(1):53-60
In this study, we examined acacetin (5,7-dihydroxy-4'-methoxyflavone), a flavonoid compound, for its effect on proliferation in human non-small cell lung cancer A549 cells. The results first reported that acacetin not only inhibited A549 cell proliferation but also induced apoptosis and blocked cell cycle progression in the G1 phase. ELISA assay demonstrated that acacetin significantly increased the expression of p53 and p21/WAF1 protein, which caused cell cycle arrest. An enhancement in Fas and its two forms of ligands, membrane-bound Fas ligand (mFasL) and soluble Fas ligand (sFasL), might be responsible for the apoptotic effect induced by acacetin. Taken together, p53 and Fas/FasL apoptotic system may participate in the antiproliferative activity of acacetin in A549 cells.  相似文献   
95.
The survival of osteoblast cells is one of the determinants of the development of osteoporosis in patients. Osthole (7-methoxy-8-isopentenoxycoumarin) is a coumarin derivative present in many medicinal plants. By means of alkaline phosphatase (ALP) activity, osteocalcin, osteopontin, and type I collagen, enzyme-linked immunosorbent assay, we have shown that osthole exhibits a significant induction of differentiation in two human osteoblast-like cell lines, MG-63 and hFOB. Induction of differentiation by osthole was associated with increased bone morphogenetic protein (BMP)-2 production and the activations of SMAD1/5/8 and p38 and extracellular signal-regulated kinase (ERK) 1/2 kinases. Addition of purified BMP-2 protein did not increase the up-regulation of ALP activity and osteocalcin by osthole, whereas the BMP-2 antagonist noggin blocked both osthole and BMP-2-mediated ALP activity enhancement, indicating that BMP-2 production is required in osthole-mediated osteoblast maturation. Pretreatment of osteoblast cells with noggin abrogated p38 activation but only partially decreased ERK1/2 activation, suggesting that BMP-2 signaling is required in p38 activation and is partially involved in ERK1/2 activation in osthole-treated osteoblast cells. Cotreatment of p38 inhibitor SB203580 [4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)-1H-imidazole] or p38 small interfering RNA (siRNA) expression inhibited osthole-mediated activation of ALP but only slightly affected osteocalcin production. In contrast, the production of osteocalcin induced by osthole was inhibited by the mitogen-activated protein kinase kinase inhibitor PD98059 (2'-amino-3'-methoxyflavone) or by expression of an ERK2 siRNA. These data suggest that BMP-2/p38 pathway links to the early phase, whereas ERK1/2 pathway is associated with the later phase in osthole-mediated differentiation of osteoblast cells. In this study, we demonstrate that osthole is a promising agent for treating osteoporosis.  相似文献   
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98.
Oxidized cholesterols belong to a subgroup of oxLDLs which play major roles in atherosclerosis. In order to investigate the contribution of oxysterols from oxLDLs in atherosclerosis, cholesterol-3-beta, 5-alpha, 6-beta-triol (α-Triol) was studied in human umbilical vein endothelial cells. We found that α-Triol concentration- and time-dependently enhanced COX-2 protein expression and mRNA production followed by PGE2 generation in human umbilical vein endothelial cells. In addition, α-Triol upregulated peNOS1177 protein phosphorylation and concentration-dependently increased nitric oxide production. eNOS1177 phosphorylation was abrogated by the PI3K inhibitor, LY294002. In studying the mechanisms involved in α-Triol-induced COX-2/PGE2 production, inhibitors of NOS, PI3K, p38, and NF-κB, effectively attenuated COX-2 protein induction and mRNA expression, suggesting that the PI3K-Akt-eNOS pathway, p38MAPK, and NF-κB are involved in α-Triol-induced COX-2 expression, and following increases in p38 and Akt phosphorylation, the concentration-dependent inhibition of COX-2 protein expression by L-NAME further suggested their involvement at the translation level. We concluded that α-Triol increases COX-2 mRNA and protein expression via coordination with the PI3K-Akt-eNOS pathway and NF-κB. Moreover, COX-2 gene expression might be regulated by activated p38 MAPK in another unknown regulation pathway. Our findings also suggested that α-Triol might contribute to the effect of induced atherosclerosis in humans through COX-2 production in endothelial cells.  相似文献   
99.

Objectives

This study aims to determine the risk factors associated with the bacterial contamination of blood cultures among adults visiting the emergency department (ED).

Methods

Clinical variables and medical records of adults with bacterial growth of blood cultures in the ED as well as the degree of ED crowding, between August 2007 and July 2008, were prospectively collected.

Results

Of the 11?491 adults who underwent blood culture sampling, the medical records of 558 (4.86%) eligible patients with bacterial growth in their blood cultures were analyzed. Most patients (366, or 3.19%) had true bacteremia, whereas 192 (1.67%) were regarded as contaminated. In multivariate analyses, ED overcrowding (scoring was based on a National Emergency Department Overcrowding Study [NEDOCS] score ≥100 points) was independently associated with blood culture contamination (odds ratio [OR], 1.58; P = .04). In contrast, other medical comorbidities, such as liver cirrhosis (OR, 0.31; P = .02), thrombocytopenia (<100?000/mm3; OR, 0.28; P = .002), or high serum levels of C-reactive protein (>100 mg/L; OR, 0.24; P < .001), were negatively associated with blood culture contamination. On further analysis of the 5 crowding categories as stratified by NEDOCS scores, which included not busy and busy (0-60 points), extremely busy but not overcrowded (60-100), overcrowded (100-140), severely overcrowded (140-180), and dangerously overcrowded (180-200), there was a strong correlation between blood culture contamination rates and the degrees of ED crowding (γ = 0.99, P < .001).

Conclusions

Emergency department overcrowding may have an adverse impact on the quality of clinical care, including increasing the risk of blood culture contamination.  相似文献   
100.

Background  

Cytokeratin 19 (CK19), a molecular marker of hepatic progenitor cells and cholangiocytes, is expressed in hepatocellular carcinomas (HCC), but not in normal hepatocytes. However, role of CK19 in HCC progression, especially when interacted with p53 and β-catenin mutations, remained largely unknown.  相似文献   
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