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61.
Wai CT Fontana RJ Polson J Hussain M Shakil AO Han SH Davern TJ Lee WM Lok AS;US Acute Liver Failure Study Group 《Journal of viral hepatitis》2005,12(2):192-198
The role of hepatitis B virus (HBV) genotypes in the outcome of acute HBV infection is unclear. In this study, we aimed to evaluate the clinical and virological features of patients with hepatitis B-related acute liver failure (HBV-ALF) in the US. Clinical and laboratory features of consecutive patients with HBV-ALF from the US ALF Study Group were analysed. Prevalence of HBV genotypes, precore stop (G1896A) and core promoter dual (T1762A, A1764T) variants among patients with HBV-ALF were compared with a cohort of 530 patients with chronic HBV infection. Thirty-four HBV-ALF patients were studied: mean age 41 years, 56% men, 25 had detectable HBV-DNA. HBV genotypes A, B, C and D were found in 36, 24, 8 and 32% patients, respectively. Precore stop and core promoter dual variants were detected in 32 and 44% of patients, respectively. Twenty-three (68%) patients survived: 14 after liver transplant, nine without transplant. Older age was the only independent factor associated with poor outcome. Compared with patients with chronic HBV infection, patients with ALF were more likely to be non-Asians (88% vs 44%, P = 0.005) and to have genotype D (32% vs 10%, P < 0.01). A higher prevalence of HBV genotype D persisted even after matching for race and HBeAg status (32% vs 16%, P = 0.007). We concluded that HBV genotype D was more frequently found in patients with HBV-ALF than those with chronic HBV infection in the US. Further studies are needed to determine if HBV genotypes play a role in the outcome of acute HBV infection. 相似文献
62.
Identification of low density lipoprotein as a regulator of Fc receptor-mediated phagocytosis. 总被引:3,自引:0,他引:3
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R D Bigler M Khoo S Lund-Katz L Scerbo M Esfahani 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(13):4981-4985
Optimal expression of the high-affinity Fc receptor for IgG (FcRI) by the human monocyte cell line U-937 requires the presence of low density lipoprotein (LDL), and neither cholesterol nor high density lipoprotein can provide the component necessary for optimal FcRI expression. Here we show that FcR-mediated phagocytosis also requires LDL. U-937 cells were cultured in medium containing interferon gamma and either fetal calf serum (FCS) or delipidated FCS (DLFCS). The phagocytosis of IgG-coated erythrocytes was measured by a colorimetric assay. U-937 cells cultured in DLFCS medium had less than 16% of the phagocytic activity of cells cultured in normal FCS medium. Phagocytosis of IgG-coated erythrocytes could be inhibited 85% by the addition of murine IgG2a myeloma protein (5 micrograms/ml). U-937 cells cultured in DLFCS medium supplemented with pure cholesterol in ethanol (10 micrograms/ml) had only 30% of the phagocytic activity of cells grown in FCS medium. Addition of very low density lipoprotein (0.2 mg of protein per ml) to DLFCS medium also failed to increase phagocytosis. However, the addition of LDL (0.2 mg of protein per ml) to DLFCS medium restored 90% of the phagocytic activity. Since neither pure cholesterol nor very low density lipoprotein restored normal phagocytic function to U-937 cells despite a normalization of cellular cholesterol content, the restoration of phagocytosis observed with LDL replacement cannot be explained by mere delivery of cholesterol by LDL. Thus, LDL is required for the expression of FcRI and FcR-mediated phagocytosis by U-937 cells and may be an important regulator of phagocytic activity of monocytes and macrophages in vivo. 相似文献
63.
Thet Zaw Lam Alfred K. Ranganathan Dwarakanathan Aung Soe Yu Khoo Tien K. 《Clinical rheumatology》2020,39(9):2501-2513
Clinical Rheumatology - This review appraises the current literature on carcinogenic risks in anti-neutrophilic cytoplasmic autoantibody (ANCA) associated vasculitis (AAV). Patients with AAV are... 相似文献
64.
Bridget D. Mathison Lindsey L. Kimble Kerrie L. Kaspar Christina Khoo Boon P. Chew 《Nutrition Research》2014
Consumption of polyphenol-rich foods is associated with lower risk from many chronic diseases. We hypothesized that a single dose of cranberry beverage would improve indices of oxidative stress, inflammation, and urinary antibacterial adhesion activity in healthy humans. Six males and 6 females (18-35 years; body mass index, 19-25 kg/m2) consumed placebo, cranberry leaf extract beverage, or low-calorie cranberry juice cocktail (LCJC) once in a randomized, double-blind, placebo-controlled cross-over experimental design trial. The washout period between beverages was 1 week. Blood was collected 0, 2, 4, 8, and 24 hours after beverage consumption for measuring oxidative and inflammatory biomarkers. Urine was collected at 0, 0 to 3, 3 to 6, 6 to 9, 9 to 12, and 24 hours postintervention to assess antibacterial adhesion activity. Consumption of cranberry leaf extract beverage elevated (P < .05) blood glutathione peroxidase activity, whereas LCJC consumption increased (P < .05) glutathione concentrations and superoxide dismutase activity compared with placebo. Cranberry leaf extract beverage and LCJC consumption had no effect on the inflammatory biomarkers measured as compared with placebo. At 0 to 3 hours postconsumption, urine from participants who consumed cranberry beverages had higher (P < .05) ex vivo antiadhesion activity against P-fimbriated Escherichia coli compared with placebo. An acute dose of cranberry beverages improved biomarkers of antioxidant status and inhibition of bacterial adhesion in urine. 相似文献
65.
Hau Wei Khoo Terrence Chi Hong Hui Salahudeen Mohamed Haja Mohideen Yeong Shyan Lee Charlene Jin Yee Liew Shawn Shi Xian Kok Barnaby Edward Young Sean Wei Xiang Ong Shirin Kalimuddin Seow Yen Tan Jiashen Loh Lai Peng Chan Angeline Choo Choo Poh Steven Bak Siew Wong Yee-Sin Leo David Chien Lye Gregory Jon Leng Kaw Cher Heng Tan 《Singapore medical journal》2021,62(9):458
INTRODUCTIONChest radiographs (CXRs) are widely used for the screening and management of COVID-19. This article describes the radiographic features of COVID-19 based on an initial national cohort of patients.METHODSThis is a retrospective review of swab-positive patients with COVID-19 who were admitted to four different hospitals in Singapore between 22 January and 9 March 2020. Initial and follow-up CXRs were reviewed by three experienced radiologists to identify the predominant pattern and distribution of lung parenchymal abnormalities.RESULTSIn total, 347 CXRs of 96 patients were reviewed. Initial CXRs were abnormal in 41 (42.7%) out of 96 patients. The mean time from onset of symptoms to CXR abnormality was 5.3 ± 4.7 days. The predominant pattern of lung abnormality was ground-glass opacity on initial CXRs (51.2%) and consolidation on follow-up CXRs (51.0%). Multifocal bilateral abnormalities in mixed central and peripheral distribution were observed in 63.4% and 59.2% of abnormal initial and follow-up CXRs, respectively. The lower zones were involved in 90.2% of initial CXRs and 93.9% of follow-up CXRs.CONCLUSIONIn a cohort of swab-positive patients, including those identified from contact tracing, we found a lower incidence of CXR abnormalities than was previously reported. The most common pattern was ground-glass opacity or consolidation, but mixed central and peripheral involvement was more common than peripheral involvement alone. 相似文献
66.
Lu Ping Tan Geok Wee Tan Vijaya Mohan Sivanesan Siang Ling Goh Xun Jin Ng Chun Shen Lim Wee Ric Kim Taznim Begam Binti Mohd Mohidin Nor Soleha Mohd Dali Siew Hoon Ong Chun Ying Wong Halimuddin Sawali Yoke Yeow Yap Faridah Hassan Kin Choo Pua Cheng Eng Koay Ching Ching Ng Alan Soo-Beng Khoo the Malaysian Nasopharyngeal Carcinoma Study Group 《International journal of cancer. Journal international du cancer》2020,146(8):2336-2347
Nasopharyngeal carcinoma (NPC) is originated from the epithelial cells of nasopharynx, Epstein–Barr virus (EBV)-associated and has the highest incidence and mortality rates in Southeast Asia. Late presentation is a common issue and early detection could be the key to reduce the disease burden. Sensitivity of plasma EBV DNA, an established NPC biomarker, for Stage I NPC is controversial. Most newly reported NPC biomarkers have neither been externally validated nor compared to the established ones. This causes difficulty in planning for cost-effective early detection strategies. Our study systematically evaluated six established and four new biomarkers in NPC cases, population controls and hospital controls. We showed that BamHI-W 76 bp remains the most sensitive plasma biomarker, with 96.7% (29/30), 96.7% (58/60) and 97.4% (226/232) sensitivity to detect Stage I, early stage and all NPC, respectively. Its specificity was 94.2% (113/120) against population controls and 90.4% (113/125) against hospital controls. Diagnostic accuracy of BamHI-W 121 bp and ebv-miR-BART7-3p were validated. Hsa-miR-29a-3p and hsa-miR-103a-3p were not, possibly due to lower number of advanced stage NPC cases included in this subset. Decision tree modeling suggested that combination of BamHI-W 76 bp and VCA IgA or EA IgG may increase the specificity or sensitivity to detect NPC. EBNA1 99 bp could identify NPC patients with poor prognosis in early and advanced stage NPC. Our findings provided evidence for improvement in NPC screening strategies, covering considerations of opportunistic screening, combining biomarkers to increase sensitivity or specificity and testing biomarkers from single sampled specimen to avoid logistic problems of resampling. 相似文献
67.
van Schalkwyk JE Alimenti A Khoo D Maan E Forbes JC Burdge DR Gilgoff S Money DM 《BJOG : an international journal of obstetrics and gynaecology》2008,115(10):1297-1302
Objective This study was designed to determine the safety of nevirapine (NVP)-based highly active antiretroviral therapy (HAART) in a cohort of HIV-positive pregnant women.
Design This was a prospective cohort study of HIV-positive pregnant women.
Population and setting All HIV-positive women treated with HAART during pregnancy from January 1997 to February 2004 at the British Columbia (BC) Women's Hospital in Vancouver, BC, Canada.
Methods Demographic and clinical data were collected to compare antiretroviral drug toxicities in women treated antenatally with NVP-based or non-NVP-based HAART. Multivariate analyses were then used to investigate determinants of toxicity.
Results From 1997 to 2004, 103 HIV-positive pregnant women received HAART. Equivalent numbers of women were initially treated with NVP-based (54%) and non-NVP-based (46%) HAART. The groups did not differ by clinical or demographic parameters and duration of HAART exposure was similar between groups. Toxicities necessitating treatment discontinuation were observed in 6 of 56 NVP-exposed women (2 cases each of grade 2, 3, and 4 toxicity) compared with 1 of 47 in the non-NVP-exposed women. First time use of NVP approached significance as a predictor for toxicity, with a toxicity rate of 12.5% (6/48) observed among those taking NVP for the first time (adjusted OR 2.68, 95% CI 0.49–14.6).
Conclusion Continuous NVP use in pregnancy resulted in a relatively higher rate of toxicity, and all cases of NVP toxicity occurred in women exposed to NVP for the first time during pregnancy. 相似文献
Design This was a prospective cohort study of HIV-positive pregnant women.
Population and setting All HIV-positive women treated with HAART during pregnancy from January 1997 to February 2004 at the British Columbia (BC) Women's Hospital in Vancouver, BC, Canada.
Methods Demographic and clinical data were collected to compare antiretroviral drug toxicities in women treated antenatally with NVP-based or non-NVP-based HAART. Multivariate analyses were then used to investigate determinants of toxicity.
Results From 1997 to 2004, 103 HIV-positive pregnant women received HAART. Equivalent numbers of women were initially treated with NVP-based (54%) and non-NVP-based (46%) HAART. The groups did not differ by clinical or demographic parameters and duration of HAART exposure was similar between groups. Toxicities necessitating treatment discontinuation were observed in 6 of 56 NVP-exposed women (2 cases each of grade 2, 3, and 4 toxicity) compared with 1 of 47 in the non-NVP-exposed women. First time use of NVP approached significance as a predictor for toxicity, with a toxicity rate of 12.5% (6/48) observed among those taking NVP for the first time (adjusted OR 2.68, 95% CI 0.49–14.6).
Conclusion Continuous NVP use in pregnancy resulted in a relatively higher rate of toxicity, and all cases of NVP toxicity occurred in women exposed to NVP for the first time during pregnancy. 相似文献
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Stonustoxin (SNTX) is a lethal factor isolated from the venom of the stonefish Synanceja horrida. Although SNTX exhibits a multitude of biological activities, the primary cause of death upon administration of the toxin is attributed to marked hypotension. We investigated the possible mechanisms underlying the vascular hyporeactivity of this novel toxin. Cumulative doses of SNTX (5-320 ng/mL) induced concentration-dependent relaxation in phenylephrine (PE)--precontracted rat aortic rings with intact endothelium. Endothelium removal abolished the relaxation induced by SNTX. Tetraethylammonium (TEA), an inhibitor of K(+) channels, partially inhibited SNTX-induced relaxation. Similarly, SNTX-induced relaxation was partially attenuated by the SP receptor antagonist (NATB), whereas the inducible iNOS inhibitor, AMT-HCl, completely abolished the relaxation caused by SNTX. From the results obtained, it can be postulated that a component of SNTX-mediated vasorelaxation is via binding of either SNTX or SP to the SP receptors that are located on the endothelial cells. Occupation of these SP receptors causes subsequent production of NO and activation of K(+) channels, thus leading to vasorelaxation of the rat aortic rings. 相似文献