HBV感染者HBV-DNA阳性血清HBeAg阴性的影响因素

目的 探讨HBV感染者HBV—DNA阳性血清HBeAg阴性的影响因素。方法 采用ms—PCR及ELISA方法分别检测HBV感染者血清中A-1896及HBeAg／IC。结果 29例HBV—DNA阳性、HBeAg阴性血清标本，HBeAg／IC阳性17例(58．7％)，单一A-1896者3例(10．3％)，HBeAg／IC及A-1896共存2饲(6．9％)。结论 HBeAg／IC形成是HBV—DNA阳性血清HBeAg阴性的主要原因，而非A-1896。     

福州市乙肝病毒基因型和基因亚型的分布及其与前C、C基因启动子变异的关系

目的 研究福州市乙肝病毒基因型和亚型分布及其与T1762/A1764、A1896变异的关系,为完善预防、诊断、治疗病毒感染的策略和方法提供科学依据. 方法 应用型特异性引物PCR法检测HBsAg阳性血清的基因型,应用PCR-RFLP方法检测基因亚型、T1762/A1764变异和A1896变异. 结果 282份HBsAg阳性血清样品中103份未能成功分型,其余179份样品中B基因型122份(68.2%),C基因型54份(30.2%),B C型3份(1.7%),未检测到其他基因型.随机选取的100份B基因型样品中,Ba亚型71份(71.0%),Bj亚型8份(8.0%),未能分亚型者21份(21.0%).54份C基因型样品中Ce亚型 31份(57.4%),Cs亚型 14份(25.9%),Ce Cs 1份(1.9%),未能分亚型者8份(14.8%).T1762/A1764变异标本9份(8.7%),Ce亚型变异率最高(29.2%),Ba亚型次之(3.3%),Cs和Bj亚型未检测到变异株,T1762/A1764变异在不同基因型和亚型间的分布差异有统计学意义(P＜0.05).A1896变异标本10份(10.0%),Ba亚型变异率最高(14.0%),Cs亚型次之(10.0%),Ce亚型最低(4.0%),不同基因型和亚型中的变异差异无统计学意义(P＞0.05).HBeAg阳性和阴性样品中的基因型和亚型分布差异无统计学意义(P＞0.05). 结论 福州市乙肝病毒以B、C基因型为主,Ba、Ce亚型占优势,HBV各基因型和亚型发生T1762/A1764、A1896变异的模式不同.     

HPLC-MS/MS法测定人血浆中的左西孟旦及其主要代谢物

建立快速、 灵敏、 易操作的LC-MS/MS法测定人血浆中的左西孟旦及其代谢物OR-1855和OR-1896的浓度。根据待测物的不同性质， 采用两套液相色谱系统和电离方式分别测定人血浆中的左西孟旦和代谢物OR-1855、 OR-1896。测定左西孟旦时， 用瑞舒伐他汀为内标， 血浆样品经甲醇沉淀蛋白， 以甲醇-15 mmol·L^-1醋酸铵-甲酸(55∶45∶0.02， v/v/v)为流动相， Capcell MG III C₁₈柱(35 mm×2.0 mm ID， 3 μm)进行分离， 采用电喷雾电离源，以选择反应监测(SRM)方式进行负离子检测。测定代谢物OR-1855和OR-1896时， 用多索茶碱为内标， 血浆样品经乙酸乙酯萃取， 以甲醇-15 mmol·L^-1醋酸铵-甲酸(65∶35∶0.1， v/v/v)为流动相， Zorbax Extend C₁₈柱(150 mm×4.6 mm ID， 5 μm)进行分离， 采用电喷雾电离源， SRM方式进行正离子检测。测定血浆中左西孟旦方法的线性范围为0.10～50.0 ng·mL^-1， 定量下限可达0.10 ng·mL^-1； 测定血浆中代谢物OR-1855和OR-1896方法的线性范围均为0.20～100 ng·mL^-1， 定量下限均可达0.20 ng·mL^-1。本方法专属性好， 准确、 快速， 适用于左西孟旦注射液的临床药代动力学研究。     

G1896A Precore Mutation and Association With HBeAg Status,Genotype and Clinical Status in Patients With Chronic Hepatitis B

Background:

Precore stop codon (G1896A) mutation is one of the commonest mutations found in patients with chronic hepatitis B. However, over the years, this mutation was not reported much in Malaysia.

Objectives:

We therefore investigated the presence of G1896A mutation in Malaysian population and its association with HBeAg status, clinical stage, hepatitis B virus (HBV) genotype and e-seroconversion rate.

Patients and Methods:

Serum samples from 93 patients confirmed as hepatitis B carriers were collected for molecular assay. The whole genome of HBV was amplified by polymerase chain reaction and directly sequenced. The precore and basal core promoter regions were analyzed for presence of mutations.

Results:

The most commonly observed mutation in the precore region was C1858T with 64.5% prevalence. The precore mutation of interest (G1896A) was identified in 25.8% of isolates. The basal core promoter mutations detected were A1762T-G1764A (26.9%), C1653T (8.6%), A1752G (10.8%) and C1766T (2.2%). No significant association was observed between G1896A mutation and HBeAg-negativity. Nonetheless, G1896A was highly prevalent among HBV genotype B. Clinical association revealed that subjects with G1896A mutations were mainly detected in asymptomatic chronic hepatitis B (58.3%) and liver cirrhosis (41.7%). One subject was diagnosed with fulminant hepatitis (4.2%) and 8.3% had hepatocellular carcinoma (HCC).

Conclusions:

Our data suggested an intermediate prevalence of G1896A mutation among Malaysian hepatitis B carriers. The stop codon mutation has a significant association with genotype B and patients with chronic hepatitis B and liver cirrhosis.     

乙型肝炎患者血清HBV前C区A1896变异的检测分析

目的了解HBsAg(+)/HBcAb(+)/HBeAb(+)的慢性乙肝病人血清乙肝病毒(HBV)DNA前C区A1896的变异情况及其与临床关系。方法对所有试验对象检测肝功能指标,根据检测结果分为丙氨酸氨基转移酶(ALT)升高组和ALT正常组。用聚合酶链反应杂交(PCR-ELISA)定量检测HBV-DNA并进一步检测HBV前C区A1896位点的变异情况。结果 38例患者中有18例HBV-DNA阳性,其中15例发生A1896位点变异,变异率为83.3%(15/18)。ALT升高组的18例中,血清HBV-DNA阳性13例,阳性率72.2%,平均浓度为9.62×106(1.10×103～1.09×108)拷贝/ml,A1896变异13例,变异率为100%(13/13)。ALT正常组的20例中,HBV-DNA阳性5例,阳性率25.00%,平均浓度2.55×104(3.28×103～4.61×104)拷贝/ml。A1896变异2例,变异率为40%(2/5)。两组比较无论在HBV-DNA阳性率,还是A1896位变异率都具有统计学差异(P<0.05)。结论 HBsAg(+)/HBcAb(+)/HBeAb(+)的慢性乙肝患者存在较高的A1896变异率,ALT升高组HBV-DNA阳性率和变异率均高于ALT正常组(P<0.05),提示HBV A1896位点变异与肝脏病变活动加重和ALT升高有关。     

Levosimendan and its metabolite OR-1896 elicit KATP channel-dependent dilation in resistance arteries in vivo

BackgroundLevosimendan and its long-lived metabolite OR-1896 produce vasodilation in different types of vessels by activating ATP-sensitive (K_ATP) and other potassium channels.MethodsIn the present study we applied intravital videomicroscopy to investigate the in situ effects of levosimendan and OR-1896 on the diameters of real resistance arterioles (rat cremaster muscle arterioles with diameters of ~ 20 μm).ResultsLevosimendan and OR-1896 induced concentration-dependent (1 nM – 100 μM) dilations to similar extents in these arterioles (maximal dilation from 23 ± 2 to 33 ± 2 μm and from 22 ± 1 to 32 ± 1 μm, respectively). The arteriolar dilations induced by the selective K_ATP channel opener pinacidil (1 nM – 10 μM) (maximal dilation from 22 ± 4 μm to 35 ± 3 μm) were diminished in the presence of the selective K_ATP channel blocker – glibenclamide (5 μM) (maximal diameter attained: 22 ± 1 μm). Glibenclamide also counteracted the maximal dilations in response to levosimendan or OR-1896 (to 23 ± 3 μm or 22 ± 5 μm, respectively).ConclusionsIn conclusion, this is the first demonstration that levosimendan and OR-1896 elicit arteriolar dilation in vivo, via activation of K_ATP channels in real resistance vessels in the rat.     

Toxicity reduction of municipal wastewater by anaerobic-anoxic-oxic process

Objective This study was conducted to optimize the operational parameters of anaerobic-anoxic-oxic （A^2/O） processes to reduce the toxicity of municipal wastewater and evaluate its ability to reduce toxicity. Methods A luminescent bacterium toxicity bioassay was employed to assess the toxicity of influent and effluent of each reactor in the A2/O system. Results The optimum operational parameters for toxicity reduction were as follows： anaerobic hydraulic retention time （HRT） = 2.8 h, anoxic HRT = 2.8 h, aerobic HRT = 6.9 h, sludge retention time （SRT） = 15 days and internal recycle ratio （IRR） = 100%. An important toxicity reduction （%） was observed in the optimized A2/O process, even when the toluene concentration of the influent was 120.7 mg·L^-1. Conclusions The toxicity of municipal wastewater was reduced significantly during the A^2/O process. A^2/O process can be used for toxicity reduction of municipal wastewater under toxic-shock loading.     

HBV S基因亚型与前C基因1896位点变异关系的初步研究

目的:研究HBV S基因亚型与前C基因1896位点变异的关系。方法:对104例病人血清用PCR技术特异性扩增前C基因1896位点突变和用PCR-RFLP技术对HBV S基因分型。结果:①1896位点变异检出率为63.46％;②武汉地区HBVS基因亚型Ⅰ感染率为68.27％,亚型Ⅱ为25.00％,亚型Ⅲ为4.81％,亚型Ⅰ Ⅱ复合感染为1.92％;③在亚型Ⅱ中,单纯野生株感染为80.77％,单纯变异株为7.7％,野生株变异株同时感染为11.54％,而占感染多数的亚型Ⅰ中,野生株和变异株的感染无差异。结论:1896位点是高频率变异位点,其变异不是随机的,而是与HBV不同的S基因亚型有关,基因亚型Ⅱ不易发生1896位点变异,受感染的机体内环境只是起促进变异的作用。