基于模糊模型的乙肝病毒传播的母婴免疫控制方法

本文研究基于模糊模型的乙型肝炎病毒传播的母婴免疫控制方法.利用总人口数恒定的假设,建立由非线性微分代数方程描述的乙肝病毒传播的动力学模型.借助干微分代数系统理论,分析乙肝病毒传播模型的无病平衡点的局部动态行为.分析表明,无病平衡点仅对某些参数取值是稳定的.基于T-S模糊模型,将母婴免疫方法看作控制变量,提出一种有效控制乙型肝炎病毒传播的策略.     

广泛接种乙肝疫苗后不同年龄人群急性乙型肝炎危险因素的对应分析

目的研究广泛开展新生儿乙肝疫苗接种后,不同年龄人群中的乙型肝炎危险因素与年龄的对应关系,以制定针对性的乙型肝炎防治措施。方法回顾性分析40例乙型肝炎病毒感染者的感染危险因素,数据分析采用对应的分析方法。结果40例乙型肝炎病毒感染者中,低年龄组、母亲怀孕及分娩时感染乙型肝炎病毒有一定的联系。结论乙型肝炎的传播途径复杂。在低年龄组人群中,母婴传播是主要的传播途径。在低年龄组人群中开展乙肝疫苗接种是预防和控制乙型肝炎的重要措施。     

水源中乙型肝炎病毒污染的可能性

乙型肝炎可以因注射器消毒不严、与乙型肝炎病人长期接触等途径进行传播,也可以通过吸血昆虫(蚊子、臭虫)传播。为了解是否尚存在其它的传播途径,我们曾对各种水源进行了乙型肝炎表面抗原(HB_sAg)的检测。     

心肌胞钙波随机性研究

钙波作为一种胞内的钙释放通道相互触发而产生的连锁反应广泛存在于多种细胞．在心肌中,由于与心律失常的发生有关,心肌细胞中的钙波近年来引起广泛关注．为了在微观上研究钙波的产生和传播过程,利用激光共聚焦钙成像技术对心肌细胞中的钙波进行了成像．实验和分析发现,钙波的起始是钙火花连续随机募集的过程,因此正常细胞中钙波发生概率很低．钙波传播过程中相邻位点开放的时间间隔接近正态分布,显示传播过程具有较大的随机性．且钙波速度越慢,位点间时间间隔的离散度越高．为了进一步研究这种随机性产生的内在机制,构建了一个数值模型对心肌细胞中的钙波进行模拟．研究证明,钙释放位点开放的随机性能够完整地解释实验中观察到的钙波传播的随机行为．实验分析和数值模拟相互印证,首次明确证明,钙波起始和传播过程的随机性,并揭示了该随机性与钙释放位点开放概率的关系．     

基于元胞自动机的生物性病原物类疾病传播模型

生物性病原物类疾病是单一植物群落中常见的一种传染病,它主要依靠风、雨和昆虫等外力传播病菌,传播过程中具有一定的潜伏性,元胞自动机是一种在时间和空间上离散,以每个个体状态的同步更新为前提来讨论系统整体性质的模型,本文利用其特点,将整个森林中的树木分为健康、潜伏期、发病期三类,以树木的营养状况和被感染时间长度为辅助变量,在考虑到树木得病后被治愈的情况后,建立了基于元胞自动机的树林生物性病原物类疾病传播模型．模拟结果表明,在不同的初始条件下,得病树所占的比例由疾病传播和被治愈的相对强度确定．疾病每次传播时,从爆发到被控制的过程具有相似的特点：随着恢复强度从小到大,初始阶段,被感染的树木迅速增加,接着进入传播速度相对缓慢的稳定过程,最终如果恢复机制足够强,则树林中的不健康树木会全部消失．     

培养基组分和发酵温度对重组酵母表达HBsAg的影响

分析酵母基因工程菌生产目的基因表达产物——乙型肝炎表面抗原的发酵过程,降低培养基中葡萄糖浓度,补充甘油和蔗糖,能使乙型肝炎表面抗原相对浓度从3．89提高至8．12,比活值增加2．69倍。根据实验观察的结果,造成发酵过程的温度序列,能合理地分配受体细胞代谢能量的消耗,使目的基因的表达量提高至13．51相对浓度。同时,对流加式操作系统中表现出的重组质粒稳定性的变化规律给予描述和解释。另外,提出了异源DNA与受体细胞的转化过程存在着一个分布,此分布对通过发酵提高乙型肝炎表面抗原的产量造成影响。     

应用蛋白组学方法筛选和鉴定乙型肝炎病毒PreS1结合蛋白

前S1蛋白（PreS1）在乙型肝炎病毒与宿主的相互作用中起至关重要的作用．为筛选乙型肝炎病毒PreS1结合蛋白,进一步探讨其在病毒感染过程中的作用,原核表达、纯化了PreS1-谷胱甘肽-S-转移酶（glutathione-S-transferase,GST）融合蛋白,利用此蛋白与HepG2细胞裂解液进行Pull-down实验,其产物进行双向凝胶电泳分离. 结果发现2个PreS1特异结合蛋白,经质谱鉴定为分子伴侣蛋白——葡萄糖调节蛋白78(GRP78)和葡萄糖调节蛋白75(GRP75)．通过免疫共沉淀和Western印迹分析证实,PreS1与GRP75之间存在相互作用．实验结果表明,GRP75为新发现乙型肝炎病毒PreS1特异结合蛋白,其与PreS1结合后的生理功能以及在HBV感染过程中的作用值得深入研究．     

122例抗HCV酶标法阳性肝病患者重叠感染的血清学分析

丙型肝炎(Hepatitisc)是一种经血液传播、性传播和母婴传播的传染病,是由丙型肝炎病毒(Hepatitisc VirusHCV)引起的非甲非乙型肝炎,它是1989年9月在日本东京召开的国际非甲非乙型肝炎学术会上正式命名的。丙型肝炎的检测由1986年间建立了抗体的RLA和ELA方法。于1992年利用ELA方法检测HCV抗体,材料来源方便,方法简单,便于临床实验开展。1材料与方法1·1材料(1)血清标本:血清标本取自于本院门诊及住院患者(诊断符合1990年上海肝炎会议诊断分型)以及来院健康体检者。(2)试剂:抗-HCV酶免试剂盒(由厦门新创科技有限公司提供)。1·2方法…     

破坏乙肝病毒中草药筛选方法的研究──乙肝病毒颗粒模型的建立

乙型肝炎是由乙型肝炎病毒引起的严重传染病。本文建立了乙肝病毒颗粒模型,并应用于中草药破坏乙肝病毒的筛选,证明标准品大黄（含生药ｌｇ／ｍｌ）抗乙肝病毒可达到１：１６０以上,且不受ｐＨ影响,证明该模型稳定、简便,可应用于大量破坏乙肝病毒中草药的筛选。     

吸入性麻醉药动力学模型定量分析

从机理分析的角度研究了吸入性麻醉药使用过程中在诱导期的数学模型,采用室分析方法,建立了人体血药浓度的药代动力学模型和吸入药量模型,并求出其精确解．然后以七氟谜用药累积记录为研究对象,进行了数值计算,算得药代动力学模型和吸入药量模型与实际测量数据的相关系数分别为0．9865和0．8874．最后给出模型拟合曲线．     

Seroprevalence of viral hepatitis in riverine communities from the Western Region of the Brazilian Amazon Basin.

The western region of the Brazilian Amazon Basin has long been shown to be a highly endemic area for hepatitis B and hepatitis D viruses. Data concerning the prevalence of hepatitis C and E viruses in this region are still scarce. In this study we investigated the presence of hepatitis A, B, C, D and E viruses infection in communities that live along the Purus and Acre rivers in the states of Acre and Amazonas within the Amazon Basin. A total of 349 blood samples were collected and tested for hepatitis A-E serological markers (antibodies and/or antigens) using commercial enzyme linked immunosorbent assays. Anti-HCV positive sera were further assayed by an immunoblot. HBsAg positive sera were subtyped by immunodifusion. The overall prevalence for hepatitis A, B, C, and E were 93.7%, 66.1%, 1.7%, and 4%, respectively. A very high prevalence of delta hepatitis (66.6%) was found among HBsAg positive subjects. Hepatitis A, B and D viruses were shown to be largely disseminated in this population, while hepatitis C and E viruses infection presented low prevalence rates in this region. The analysis of risk factors for HBV infection demonstrated that transmission was closely associated with sexual activity.     

Hepatitis B in China： from Guideline to Practice

Chronic hepatitis B infection is a very important health problem in China, which is carrying an enormous economic and social burdens. The major routs of chronic hepatitis B infection in China are mother-infant vertical transmission and early childhood horizontal transmission. After more than 10 years implementation of universal vaccination against hepatitis B in newborns and safety injection in health care settings, the prevalence of HBsAg in general population has decreased from 9.75% to around 7%. In China, patients with hepatitis are cared by either hepatologists or physicians of infectious diseases. The Chinese Society of Hepatology, and Chinese Society of Infectious Diseases jointly issued an evidence-based guideline on the prevention and treatment of chronic hepatitis B in 2005. This guideline concisely describes the virology, epidemiology, natural history and prevention, as well as diagnosis and management of chronic hepatitis B. It also highlights the importance of active viral replication in disease progression in chronic HBV infection and explicitly states the necessity of antiviral therapy in patient care. The cornerstone of anti-hepatitis B therapy is optimal use of interferons or nucleos(t)ide analogs in those patients with active viral replication and elevated serum transaminase levels. Through an independent continue medical educational agency, a panel of selected speakers were trained to give well-formatted talks on the key points of the guideline in over 60 major cities across China. This educational campaign among health care providers has greatly improved the awareness and the stand of care for antiviral therapy.     

Hepatitis B in China: from Guideline to Practice

Chronic hepatitis B infection is a very important health problem in China, which is carrying an enormous economic and social burdens. The major routs of chronic hepatitis B infection in China are mother-infant vertical transmission and early childhood horizontal transmission. After more than 10 years implementation of universal vaccination against hepatitis B in newborns and safety injection in health care settings, the prevalence of HBsAg in general population has decreased from 9.75% to around 7%. In China, patients with hepatitis are cared by either hepatologists or physicians of infectious diseases. The Chinese Society of Hepatology, and Chinese Society of Infectious Diseases jointly issued an evidence-based guideline on the prevention and treatment of chronic hepatitis B in 2005. This guideline concisely describes the virology, epidemiology, natural history and prevention, as well as diagnosis and management of chronic hepatitis B. It also highlights the importance of active viral replication in disease progression in chronic HBV infection and explicitly states the necessity of antiviral therapy in patient care. The cornerstone of anti-hepatitis B therapy is optimal use of interferons or nucleos(t)ide analogs in those patients with active viral replication and elevated serum transaminase levels. Through an independent continue medical educational agency, a panel of selected speakers were trained to give well-formatted talks on the key points of the guideline in over 60 major cities across China. This educational campaign among health care providers has greatly improved the awareness and the stand of care for antiviral therapy.     

Passive Immunization against Exposure to Hepatitis B Virus in the Military: Potential and Possibilities

The value of standard γ-globulin with a low titer of antibody to hepatitis B surface antigen (anti-HB_s) vs hepatitis B immune globulin (HBIG) in prevention of icteric hepatitis B in the military is unclear. Although recent studies have shown a decrease in icteric hepatitis after administration of both types of γ-globulin in populations where acquisition of hepatitis B virus (HBV) is most likely the result of nonparenteral transmission, the data pertaining to parenteral exposure suggest that HBIG delays the incubation period of HBV and decreases the development of passive-active immunity. Since no studies have demonstrated efficacy of standard γ-globulin or HBIG in a drug-using population where multiple HBV exposures are likely, the results observed in most trials are not comparable to hepatitis B associated with drug abuse in the military. Therefore, before a recommendation for use of routine γ-globulin or HBIG can be made for drug-related hepatitis in the military, efficacy of standard γ-globulin and/or HBIG should be demonstrated in this population.     

社区居民乙肝防控知识知晓情况调查及乙肝歧视的影响因素分析

目的:了解社区居民乙肝防控知识知晓情况并分析乙肝歧视的影响因素。方法:采用分层整群随机抽样方法选取天津市鸿顺里社区1276名居民进行问卷调查,每人发放一份问卷,回收后统计居民乙肝防控知识的知晓情况及乙肝歧视现状,并通过多因素Logistic回归分析乙肝歧视的影响因素。结果:共回收1214份有效问卷,回收率为95.14%(1214/1276),乙肝5条主要传播途径中知晓经血液传播最高为70.18%(852/1214),知晓经共用牙刷及剃须刀传播为48.76%(592/1214),知晓经母婴传播为37.73%(458/1214),知晓经性生活传播为34.68%(421/1214),知晓经污染的医疗器械传播为34.18%(415/1214),5条传播途径均知晓为27.92%(339/1214);90.77%(1102/1214)的调查者知晓"乙肝是否具有传染性",乙肝知识的总体知晓率为21.91%(266/1 214)。79.90%(970/1214)的调查对象不愿意和乙肝患者恋爱/结婚,60.96%(740/1214)的调查对象不愿意和乙肝患者共同进餐;无歧视、中轻度歧视及重度歧视的比例分别为24.87%(302/1214)、50.91%(618/1214)及24.22%(294/1214);不同年龄、职业、文化程度、月收入人群之间乙肝歧视程度的差异具有统计学意义(P<0.05)。Logistic回归分析显示年龄、职业、文化程度、月收入均是造成乙肝歧视的影响因素。结论:天津市鸿顺里社区居民的乙肝防控知识知晓率较低且歧视现象严重,应加强对乙肝知识的宣传教育,纠正对乙肝的歧视心态。     

Acute hepatitis B in patients in Britain related to previous operations and dental treatment.

The frequency of transmission of hepatitis B virus infection from health service staff to patients was assessed from reports of confirmed cases of acute clinical hepatitis in 1980-3. During the four years 4505 reports (91% of the total) included replies to a question about recent operations; 153 patients (3.4%) had this history. Transfused blood or blood products were considered the source for 27 cases (0.06%). Eleven patients (0.02%) were infected in two clusters, both in cardiac surgery units; six were caused by a perfusion technician, who was a symptomless carrier, and five by a surgical registrar during the incubation period of an acute hepatitis B infection. The estimated average annual risk of a patient developing acute hepatitis B as part of a cluster caused by staff during surgical procedures was one in a million operations. For another 11 patients blood transfusion could not be excluded as a source. Where no association between surgery and hepatitis was found the incidence of a history, lay between 2.3 and 2.6%. The Hospital In-Patient Enquiry data showed that about 2.4% of the population had had operations in a six month period. These findings suggest that transmission of hepatitis B infection from staff to patients is rare in Britain and that the small risk could be eliminated by attention to measures to preserve asepsis and by immunising staff at risk.     

Viral hepatitis E: its epidemiological characteristics in the Republic of Tajikistan

The characteristic feature of the Republic of Tajikistan, as well as other republics of Central Asia, is the wide spread of virus hepatitis E. The epidemiology of this grave disease, recently known as virus hepatitis non A, non B with the fecal-oral mechanism of transmission of this infection, has been yet insufficiently studied. The article points out to the specific character of this infection which essentially differs, both epidemiologically and clinically, from other enteric hepatitis (hepatitis A), also hyperendemic for the republic. The results of the study of the immunostructure of the population with respect to both hepatitis E and hepatitis A are presented.     

Hepatitis B virus infection in dental surgical practice.

Sixty-one dental surgeons at King''s College Hospital were interviewed to establish the incidence of attacks of viral hepatitis and to relate this to environmental risk factors. Six (10%) had a history of hepatitis, in one case due to infection with the hepatitis B virus. Screening blood for HBsAg by radioimmunoassay showed no carriers of the antigen, but transient antigenaemia was observed in one dentist. Antibody to HBsAg, tested by radioimmunoassay, was detected in four dentists (7%), only one of whom had had clinical hepatitis. Dental surgeons may be more at risk from infection with the hepatitis B virus than the general population, although this should be minimised in hospital practice, where the most infected patients will already have been identified and appropriate precautions can be taken. The risk of transmission from an antigen-positive dentist to his patients is probably much smaller, and there is no evidence to restrict his clinical activities.     

Hepatitis B in a high prevalence New Zealand population: a mathematical model applied to infection control policy

Background

Chronic hepatitis B (CHB) is a vaccine preventable disease of global public health importance. The prevalence of CHB in New Zealand's Tongan population is over 10%, a level consistent with endemic infection, which contrasts to the low overall New Zealand prevalence (<0.5%). Despite the introduction of infant vaccination in 1988, coverage among Tongan children is estimated to be only 53%.

Aims

To estimate the population benefit of additional public health control measures besides ‘business as usual’ infant vaccination for hepatitis B in high prevalence populations.

Methods

A mathematical model of hepatitis B virus (HBV) transmission was used to predict future CHB prevalence in the New Zealand Tongan population under different infection control strategies.

Results

Prevalence of CHB is predicted to plateau at 2% in the New Zealand Tongan population if coverage remains at current levels, which are therefore insufficient to achieve long-term elimination of HBV. The critical proportion of immunisation coverage for elimination of the virus is estimated to be 73%. The effect of screening for HBV carriage and early disease management was unable to be quantified, but is likely to reduce the population burden of HBV infection and thus contribute to accelerating elimination.

Conclusions and recommendations

Mathematical models are a useful tool to forecast the future burden of CHB under a range of control strategy scenarios in high prevalence populations. Serosurveillance and targeted vaccination has similarly arrested HBV transmission in time-series prevalence studies from Taiwan and Alaska. Such a policy may demonstrate similar efficacy in New Zealand ethnic groups with endemic HBV infection.