乙型肝炎血清学标志物与HBV-DNA含量关系的探讨

目的：为了进一步探讨乙型肝炎患者血清中HBV-DNA含量与HBV血清学标志物之间的关系，了解荧光定量聚合酶链反应（FQ-PCR）检测乙型肝炎病毒的应用价值。方法：应用酶联免疫吸附试验（ELISA法）检测510例来自我院门诊就诊者和住院患者血清标本中的特异性抗原抗体，并同时应用荧光定量PCR分析系统测定血清标本中HBV-DNA的含量进行分析。结果：经ELISA法与FQPCR法检测的510例血清标本中，51例“大三阳”（HBsAg＋HBeAg＋HBcAb）的血清标本，其HBV—DNA检出数均呈阳性，阳性率为100％，其HBV-DNA的拷贝数范围为10^5～10^9／ml 76例“小三阳”（HBsAg＋HBeAb＋HBcAb）的血清标本，其HBV-DNA检出的阳性率为47．4％，HBV-DNA的拷贝数范围为10^4～10^7／ml。结论：HBV-DNA是乙型肝炎病毒感染和复制的特异性指标。应用FQ-PCR技术检测乙型肝炎病毒，具有较高的灵敏度和特异性，其操作简便，定量准确，结果可靠，它比HBV血清学标志物更能反映乙型肝炎病毒在体内的存在和真实复制状况，在HBV-DNA感染诊断，特别是药物疗效的观察中，具有良好的应用价值。因此，HBV-DNA与血清学标志物的相互关系是本文研究的课题。

核酸扩增检测结核杆菌DNA与抗酸杆菌涂片镜检结果的比较

目的通过两种不同的检验方法对肺结核患者进行检查,以确定不同的检验方法在诊断上的应用价值。方法对患者痰液、胸腔积液、血清进行聚合酶链反应（polyerase chain reaction,PCR）和涂片抗酸杆菌镜检,并用18例非结核病患者作为对照组。结果患者痰液、血清、胸腔积液结核杆菌PCR的检测阳性率明显高于涂片法,其中尤以胸腔积液PCR检测阳性率最高为78.5%,与国内大多数文献报道的56%~87%结果相仿。结论 PCR检测技术对临床上肺结核病的诊断和鉴别诊断有较高的应用价值。

肺结核早期诊断中不同检验方法的应用

目的探讨肺结核早期应用不同检验方法的诊断价值,以提高肺结核早期的诊断准确性。方法将52例肺结核患者作为A组,同时将30例健康体检者作为B组,分别对所有患者进行痰查结核菌、皮肤结核菌素纯蛋白衍化物(PPD)、结核抗体及血清聚合酶链反应(PCR)检查,对比两组痰查结核菌、PPD、结核抗体及PCR阳性率,同时分析各检查方法对肺结核早期的诊断价值。结果 A组痰查结核菌、PPD、结核抗体及PCR阳性率分别为23.08%、48.08%、86.54%及67.31%均明显高于B组的0%、23.33%、6.67%及13.33%(P<0.05)。且在A组中,结核抗体明显高于痰查结核菌、PPD及PCR阳性率(P<0.05)。经ROC分析显示,PPD、PCR阳性及结核抗体阳性对肺结核早期诊断均有诊断价值(P<0.05),且结核抗体阳性的诊断价值更显著(P<0.05)。结论 PCR阳性及结核抗体阳性均可作为肺结核早期诊断的指标,且以PCR阳性率诊断价值更高。

不同检验方法对肺结核早期诊断的应用

目的通过不同的检验方法对肺结核患者进行检查,以确定不同检验方法在诊断上的应用意义。方法对患者进行痰、胸水、血清聚合酶链反应(Polyerase Chain ReactionPCR)和涂片结核菌检查及皮肤结核菌素纯蛋白衍化物(PPD)试验,并用18例非结核病患者作为对照组。结果患者痰、血清和胸水结核杆菌的检出阳性率明显高于涂片法和PPD皮试法,其中尤以胸水PCR检测阳性率最高为76.5%。与国内大多散文献报道的56%～87%结果相仿。结论PCR检测技术对临床上肺结核病的诊断和鉴别诊断有较高的应用价值。

Viral Genotypes and Associated Risk Factors of Hepatocellular Carcinoma in India

Objective This study aims to investigate the etiological relationship among hepatitis B virus （HBV）, hepatitis C virus （HCV）, and alcohol as risk factors in a cohort of hepatocellular carcinoma （HCC） patients from India. The clinical and biochemical profiles and tumor characteristics in the HCC cases were also evaluated. Methods A total of 357 consecutive cases of HCC fulfilling the diagnostic criteria from the Barcelona-2000 EASL conference were included in the study. The blood samples were evaluated for serological evidence of HBV and HCV infection, viral load, and genotypes using serological tests, reverse transcription-polymerase chain reaction, and restriction fragment length polymorphism. Results The male/female ratio for the HCC cases was 5.87：1. Majority of the HCC patients （33.9%） were 50 to 59 years of age, with a mean age of 4±13.23 years. More than half the cases （60.8%） had underlying cirrhosis at presentation. Among the HCC patients, 68.9% were HBV related, 21.3% were HCV related, 18.8%, were alcoholic, and 18.2% were of cryptogenic origin. The presence of any marker positive for HBV increased the risk for developing HCC by almost 27 times [OR： 27.33; （12.87-60.0）]. An increased risk of 10.6 times was observed for HCC development for cases positive for ally HCV marker [OR： 10.55; （3.13-42.73）]. Heavy alcohol consumption along with HCV RNA positivity in cirrhotic patients was found to be a risk for developing HCC by 3 folds ]OR： 3.17; （0.37-70.71）]. Conclusions Patients of chronic HBV infection followed by chronic HCV infection were at higher risk of developing HCC in India. Chronic alcohol consumption was found to be a risk factor in cirrhotic cases only when it was associated with HCV RNA positivity. Most of the patients had a large tumor size （〉5 cm） with multiple liver nodules, indicating an advanced stage of the disease thus making curative therapies difficult.

Biovars and Serotypes of Ureaplasma Urealyticum among Chinese Women Undergoing Routine Gynecologic Exam, Women with Sexually Transmitted Infections, and Female Sex Workers

Objectives: To characterize the distribution pattern of biovars and scrotypes or Ureaplasma urealyyicum in normalhealthy women, sexually transmitted infections clinic clients,and in sex workers. Methods: We cultured cervical swabs taken from 261physical check-up clients, 599 STI clinic outpatients and 98 sexworkers using commercial selective medium. Some positivecultures were further biotyped and serotyped by PCR. Results: (1) U. urealyticum is more commonly isolated in sexworkers (90.8%) than in the physical check-up group (60.9%)or the STI outpatient group (61.3%) (P<0.001). (2) Biovar 1of U. 'realyticum (95.0%), especially single infection ofserotype 1. 3, and 6 of biovar 1, is commonly found in healthywomen. (3) Biovar 2 infection of U urealyticum is moreprevalent in sex workers (28.1%) and STI outpatients group(26.6%) than that in the physical check-up group (4.9%) (P<0.001). (4) Mixed infection caused by more than one serotypeof U urealyticum increased from physical check-up group(8.6%) to STI utpatients (12.4%) to sex workers (23.9%) (P<0.01). (5) There is no statistically significant difference in thedistribution of serotype 1, 3, and 6 of biovar 1 among thesethree groups (P=0.763). (6) The PCR method described here isrelatively simple, rapid and specific for the biotyping andserotyping of biovar 1 of U urealyticum. Conclusion: We should pay more attention to biovar 2 andmixed infections of U. urealyticum than single infection ofhiovar 1 in clinic practice. PCR is a good method for biotypingand serotvping.

A Molecular Epidemiology Analysis of HIV in Shenzhen and HIV Env Gene Variation Replication Analysis

Objective: To analyze molecular trends of the HIV epidemic in Shenzhen. Methods: Serum collected from Shenzhen AIDS patientsbetween 1992-1999 was analyzed using molecular techniques.DNA fragments of the HIV-1 Env gene were amplified bynested PCR from uncultured peripheral blood mononuclearcells (PBMCs) from these serum samples. The C2-C3 region ofthe Env gene was sequenced and analyzed. Specific high-riskbehaviors were also analyzed. Results: We found that the transmission of HIV in the citywas mainly through sexual behaviors (46.0%). There werefour HIV-1 subtypes: B', B, C and E with 6.31%, 7.95%,3.09% and 8.92% gene divergence inside each subtype inShenzhen. These results suggested that epidemic times were 6,8, 3 and 9 respectively. The main cpidemic subtypes were Eand B strains. AIDS patient's antigenic variation was slightlyhigher than that of HIV infected individuals. Conclusion: Surveillance data reflect trends and theepidemic time of HIV which will be useful for policy makersto formulate effeive strategies of HIV/AIDS prevention and control in Shenzhen.

Assessment of polymerase chain reaction and serology for detection of chlamydia pneumoniae in patients with acute respiratory tract infection

OBJECTIVE: To study Chlamydia pneumoniae (C. pneumoniae) infection in 110 patients with respiratory tract infection admitted to our hospital from January to December 1995 in Nanjing. METHODS: Sputum and throat swab specimens were taken and C. pneumoniae DNA was detected by using polymerase chain reaction (PCR) with the HM-1-HR-1 primer pair. At the same time, serum samples were taken and immunoglobulin G and M (IgG and IgM) fractions of antibodies to C. pneumoniae were studied by microimmunofluorescence test. RESULTS: Prevalence of specific IgG was 70% in patients with respiratory tract infection. Seventeen patients (15.5%) were serologically diagnosed as having recent C. pneumoniae infections and 12 patients (10.9%) had positive PCR in sputum and/or swab specimens. The total positive rate was 22.7% (25/110) detected by PCR combined with serological tests. Acute infection of C. pneumoniae was common in patients with asthma (57.1%), pneumonia (35.0%), COPD (25.9%) and bronchitis (25.0%). Clinical features between C. pneumoniae infection and non-C. pneumonia infection showed no significant differences. CONCLUSIONS: Chlamydia pneumoniae is an important pathogen that causes infection of the human respiratory tract and attention should be drawn to this special illness.

An accurate,high-speed,portable bifunctional electrical detector for COVID-19

Coronavirus disease 2019(COVID-19),caused by SARS-CoV-2,has rapidly spread and caused a severe global pandemic.Because no specific drugs are available for COVID-19 and few vaccines are available for SARS-CoV-2,accurate and rapid diagnosis of COVID-19 has been the most crucial measure to control this pandemic.Here,we developed a portable bifunctional electrical detector based on graphene fieldeffect transistors for SARS-CoV-2 through either nucleic acid hybridization or antigen-antibody protein interaction,with ultra-low limits of detection of~0.1 and~1 fg mL^(−1) in phosphate buffer saline,respectively.We validated our method by assessment of RNA extracts from the oropharyngeal swabs of ten COVID-19 patients and eight healthy subjects,and the IgM/IgG antibodies from serum specimens of six COVID-19 patients and three healthy subjects.Here we show that the diagnostic results are in excellent agreement with the findings of polymerase chain reaction-based optical methods;they also exhibit rapid detection speed(~10 min for nucleic acid detection and~5 min for immunoassay).Therefore,our assay provides an efficient,accurate tool for high-throughput point-of-care testing.

Serological Investigation of Laboratory-Confirmed and Suspected Ebola Virus Disease Patients During the Late Phase of the Ebola Outbreak in Sierra Leone

This study aimed to investigate the serological characteristics of Ebola virus(EBOV) infection during the late phase of the Ebola outbreak in Sierra Leone. In total, 877 blood samples from 694 suspected Ebola virus disease(EVD) cases assessed from March to December 2015, were analyzed via real-time reverse transcription polymerase chain reaction(RT-PCR) for viral RNA and enzyme-linked immunosorbent assay(ELISA) and Luminex to detect antibodies against EBOV. Viral load and EBOV-specific IgM/IgG titers displayed a declining trend during March to December 2015. Viral RNA load decreased rapidly at earlier stages after disease onset, while EBOV-specific IgM and IgG still persisted in 58.1%(18/31) and 93.5%(29/31) of the confirmed EVD patients and in 3.8%(25/663) and 17.8%(118/663) of the RNA-negative suspected patients in the later phase, respectively. Dynamic analysis of longitudinally collected samples from eight EVD patients revealed typically reversed trends of declining viral load and increasing IgM and/or IgG titers in response to the EBOV infection.The present results indicate that certain populations of Sierra Leone developed immunity to an EBOV infection in the late phase of the outbreak, providing novel insights into the risk assessment of EBOV infections among human populations.