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The cytoprotective effects of prostaglandins have been utilized in the prevention of hepatitis B virus reactivation after liver transplantation. This pilot study evaluated the effects of oral prostaglandin E2 (PGE2) in chronic viral hepatitis B and C. Twenty patients with chronic hepatitis B and 20 patients with chronic hepatitis C received 4mgday–1 PGE2 for 6 months. The lymphocyte antiviral enzyme 2',5'-oligoadenylate synthetase (2',5'-OAS) and peripheral blood monocyte procoagulant activity (PCA) were measured before, during and after the treatment. Three of 20 hepatitis B and five of 20 hepatitis C patients withdrew from the study. Eight of 17 hepatitis B patients responded: in seven of these eight patients, serum alanine aminotransferase (ALT) levels normalized; loss of viral replication was sustained in all eight patients; and seroconversion from hepatitis Be antigen (HBeAg) to hepatitis Be antibody (HBeAb) positivity occurred in seven patients over the 48-week duration of this study. In 14 of the 15 hepatitis C patients, hepatitis C virus (HCV) RNA remained detectable and the serum ALT levels remained elevated. 2',5'-OAS levels and PCA values did not correlate with other markers of response to PGE2 therapy in either chronic hepatitis B or C. In summary, PGE2 was associated with sustained loss of viral replication in 47% of chronic hepatitis B patients; no beneficial effects were apparent in chronic hepatitis C.  相似文献   
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目的 建立一种快速、灵敏的高效液相色谱-串联质谱(HPLC-MS/MS)方法以测定人血浆中对乙酰氨基酚浓度,并应用于两种对乙酰氨基酚制剂的人体药代动力学和生物等效性研究。方法 以替硝唑为内标,200μL血浆样品经5倍于其体积的乙酸乙酯液液萃取,再经Waters XBridge? C18柱等度洗脱分离后导入串联质谱,以正离子多反应监测模式进行定量分析,对乙酰氨基酚和内标的选择性反应离子对分别是m/z 152→110和248→121。方法经验证后应用于19名健康受试者单剂量空腹口服两种对乙酰氨基酚制剂500mg后药代动力学和生物等效性的研究。结果 血浆中对乙酰氨基酚在0.1~8.0 μg·mL-1范围内线性良好(r2 > 0.99),最低检测限为 0.1 μg·mL-1,提取回收率为91.0%~98.7%,日内和日间准确度分别为98.8%~111.3% (精密度:CV ? 9.03%)和94.9%~102.6% (精密度:CV ? 10.68%)。生物等效性试验中,受试制剂与参比制剂的主要药代动力学参数Cmax、AUC0-t和AUC0-∞ 几何均值比的90%置信区间分别为83.50%~105.79%,94.25%~101.54%和93.24%~101.02%,均落在生物等效可接受标准80.00%~125.00%范围内。结论 所建立测定人血浆中对乙酰氨基酚浓度的HPLC-MS/MS法具有快速灵敏、回收率高、选择性好的特点,适用于对乙酰氨基酚片人体药代动力学和生物等效性研究。受试制剂与参比制剂在人体内吸收速度和程度相似,两种制剂生物等效。  相似文献   
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Background: The impact of a low-glucose peritoneal dialysis (PD) regimen on biomarkers of peritoneal inflammation, fibrosis and membrane integrity remains to be investigated.♦ Methods: In a randomized, prospective study, 80 incident PD patients received either a low-glucose regimen comprising Physioneal (P), Extraneal (E) and Nutrineal (N) (Baxter Healthcare Corporation, Deerfield, IL, USA) (PEN group), or Dianeal (control group) for 12 months, after which both groups continued with Dianeal dialysis for 6 months. Serum and dialysate levels of vascular endothelial growth factor (VEGF), decorin, hepatocyte growth factor (HGF), interleukin-6 (IL-6), macrophage migration inhibitory factor (MIF), hyaluronan (HA), adiponectin, soluble-intracellular adhesion molecule (s-ICAM), vascular cell adhesion molecule-1 (VCAM-1) and P-selectin, and dialysate cancer antigen 125 (CA125), were measured after 12 and 18 months. This paper focuses on results after 12 months, when patients in the PEN group changed to glucose-based PD fluid (PDF).♦ Results: At the end of 12 months, effluent dialysate levels of CA125, decorin, HGF, IL-6, adiponectin and adhesion molecules were significantly higher in the PEN group compared to controls, but all decreased after patients switched to glucose-based PDF. Macrophage migration inhibitory factor level was lower in the PEN group but increased after changing to glucose-based PDF and was similar to controls at 18 months. Serum adiponectin level was higher in the PEN group at 12 months, but was similar in the 2 groups at 18 months. Body weight, residual renal function, ultrafiltration volume and total Kt/V did not differ between both groups. Dialysate-to-plasma creatinine ratio at 4 h was higher in the PEN group at 12 months and remained so after switching to glucose-based PDF.♦ Conclusion: Changes in the biomarkers suggest that the PEN PD regimen may be associated with better preservation of peritoneal membrane integrity and reduced systemic vascular endothelial injury.  相似文献   
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Periodontal bio‐repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad‐based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders.  相似文献   
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