非肝炎口腔科患者血清及唾液中HGV 和TTV感染率的调查

目的 检测杭州地区非肝炎口腔科患者血清和唾液标本中庚型肝炎病毒（HGV）和输血传播病毒（TTV）感染率，进一步了解HGV和TTV传播途径和感染的高危人群。方法 分别从上述患者血液和唾液标本中提取RNA和DNA，采用逆转录-套式聚合酶链反应（RT-Nested PCR）和半套式聚合酶链反应（Hemi-nested PCR)分别检测HGV5′-NCR RNA和TTV N22区DNA，部分DNA，部分HGV和TTV扩增产物克隆后进行核苷酸序列测定。结果 226例血清标本中，仅HGV阳性27例（11.9%）、仅TTV阳性21例（9.3%）、HGV和TTV均阳性7例（3.1%）；226例唾液标本中，仅HGV阳性10例（4.4%）、仅TTV阳性9例（3.9%）、HGV和TTV均阳性2例（0.9%）；未见血清标本HGV和/或TTV检测结果阴性而唾液标本阳性者。2例患者血清标本及唾液标本HGV和TTV均阳性的扩增产物分别与报道的HGV和TTV核苷酸序列比较，同源性为88.65%～91.49%和65.32%～66.67%，但各自的血清标本与唾液标本HGV和TTV扩增产物同源性分别高达98.58%～99.29%和98.65%～98.20%。结论 杭州地区非肝炎口腔科患者HGV或TTV感染率均较高，其中部分携带病毒的患者唾液中均可检出HGV或TTV，提示HGV或TTV可能存在唾液传播途径，口腔科医师则是HGV或TTV感染的高危人群。     

兰州地区献血员及静脉毒瘾者血清中TT病毒核酸检测及意义

目的 研究兰州地区献血员及静脉毒瘾者中TT病毒(TTV)的感染状况。方法 利用套式PCR技术检测献血员及静脉毒瘾者血清中TTV DNA。结果 献血员中TTV DNA检出率为7.5％(9/120)。静脉毒瘾者中TTVDNA枪出牢为26.8％(15/56),明显高于献血员组,结论 首次报道兰州地区存在TTV感染。静脉毒瘾者为了TTV感染的高危人群,其致病性较弱。关于TTV的病原学、流行病学、病理学及临床意义等有待进一步探索。     

急性非甲-庚型肝炎病人血清TTV DNA检测分析

目的为了解非甲-庚型肝炎的病原学感染状况,对献血员24例、急性非甲-庚型肝炎31例血清采用PCR技术进行输血传播病毒(TTV)检测。结果献血员TTV DNA阳性率为12.5％(3/24);急性非甲-庚型肝炎阳性率为41.94％(13/31),两者差异有非常显著意义(P<0.001)。结论 TTV除导致肝炎外还能以携带方式存在,深入研究TTV对肝炎和携带者的防治具有重要意义。     

血液透析患者乙、丙、庚型肝炎病毒感染状况分析

目的 探讨血液透析病人（HDP）乙型肝炎病毒（HBV）、丙型肝炎病毒（HCV）、庚型肝炎病毒（HGV）的感染状况、感染方式及预防措施。方法 对160例HDP及30例对照组定期预留血清,检测HBsAg、抗HBs、HBeAg、抗HBe 、抗HBc、HBV DNA、抗HCV、HCV RNA、抗HGV。结果 HDP的HCV、HGV感染率明显高于对照组（P＜0.01及P＜0.05）。HBV感染率高于对照组,但其差异显著性（P＞0.05）。血透加输血组肝炎病毒感染率明显高于单纯血透组（P＜0.01）。肝炎病毒感染率随透析时间的延长,感染率逐渐增高。结论 HDP HCV、HGV感染率高,其中输血是一重要因素,其次与血液透析本身的医源性感染有关。故应加强对献血员的筛选,尽量少输血,加强透析过程中的消毒隔离措施。     

输血传播性病毒的流行病学及临床研究

目的:观察分析不同人群中TTV(transfusion transmitted virus)感染状况及相关临床意义。方法:在TTVORF1设计引物,建立巢式聚合酶链反应,检测不同人群中血清TTV DNA,并对比观察肝炎病人的临床表现。结果:29例健康人群,27例职业献血员,56例乙型肝炎,31例丙型肝炎和47例非甲～非庚型肝炎患者中,TTV DNA阳性率分别为6.9％、3.7％、23.2％、25.8％和42.6％。3种肝炎病人中,TTV DNA阳性和阴性组间4项主要临床指标无显著差异。结论:健康人群和职业献血员存在TTV健康携带者。非甲～非庚型肝炎患者TTV感染率最高。乙型和丙型肝炎患者重叠TTV感染较常见。3种肝炎病人中,合并TTV感染组与非感染组临床表现无明显差异。TTV的致病性尚待深入研究。     

重庆地区HGV感染的分子流行病学

目的 探讨重庆地区HGV感染和基因型特征，了解致病性和传播途径。方法 用RT-PCR和ELlSA方法检测685例献血员和76例血液透析患者HGV感染状况，比较肝功能和重叠感染情况并进行部分病例随访；进行HGV 5-NCR测序。结果 本地存在HGV感染．血液透析患者HGV RNA阳性率(36％)明显高于献血员抗-HGV阳性率(3％)，约半数透析患者HGV合并HCV和HBV感染；基因分型表明属于第3组3b亚型。结论 HGV主要经血传播，感染HGV透析患者未发现有明显致病性；基因分型有助于深入探讨病毒致病性和变异。     

百色少数民族地区结核病患者TTV和HGV感染的调查

目的了解百色少数民族地区结核病患者输血传播病毒(transfusion transmitted virus,TTV)和庚型肝炎病毒(hepeatitis G virus,HGV)的感染状况及临床意义。方法应用酶联免疫法(ELISA)检测712例结核病患者及500人健康人群血清抗-TTV和抗-HGV,对抗-TTV阳性者用PCR法检测TTV DNA,抗-HGV阳性者用逆转录套式聚合酶链反应法(PT-nPCR)检测HGV RNA,分析结核病患者TTV DNA或HGV RNA阳性者临床特征。结果结核病患者TTV感染率16.71%,健康人群5.60%;结核病患者HGV感染率14.61%,健康人群2.60%;配对比较差异有显著性(P<0.01);结核病患者TTV与HGV感染率具有随年龄增长呈递增趋势,男性高于女性(P<0.05),感染者有过输血史和注射史的比率比非感染者高(P<0.05),在抗结核治疗中感染者比非感染者容易出现抗结核药物所致肝损害(P<0.01)。结论结核病患者对TTV和HGV有较高的感染率,反复注射及免疫功能低下可能是增加TTV和HGV感染的原因,感染者在抗结核治疗中可能更容易出现肝损害。     

泉州地区肝炎患者TTV感染状况调查

近年来,人们注意到除HAV、HBV、HCV、HDV、HEV和HGV等肝炎病毒外,仍有5％～10％的肝炎患者不能确定原因。1997年底Nishizawa等使用代表性差异分析法(RDA)首次从1例非A～G型的输血后肝炎患者血清中分离到一种新的单链DNA的病毒基因,暂命名为输血传播病毒(transfusiontransmitted virus,TTV)。我们根据公布的TTV序列,设计了两对特异性引物,建立了检测血清TTV DNA的巢式PCR方法,对泉州地区各类型肝炎患者TTV感染状况进行调查,报道     

丙型肝炎病毒感染的不同人群HCV RNA定量研究

目的了解丙型肝炎病毒感染的不同人群血清HCV RNA水平,比较定性和定量PCR结果,探讨HCV RNA含量与血清ALT的相关性.方法采用荧光定量PCR和逆转录巢式定性PCR同时检测136例丙型肝炎病毒感染者血清HCV RNA,并测定定量PCR(+)者血清ALT.用相关系数分析HCV RNA含量与血清ALT的关系.结果定性PCR阳性率为80.88%,定量PCR阳性率为77.94%.两者相对符合率为94.12%.定量PCR(+)血清(106例)HCVRNA含量在107.04～1010.96拷贝·L-1.无症状献血员HCV RNA含量显著低于慢性丙型肝炎、肝硬变和肝细胞癌患者(P＜0.05),肝细胞癌患者血清ALT水平显著低于慢性丙型肝炎(P＜0.05).HCVRNA滴度与血清ALT呈正相关(r=0.61,P＜0.01).结论定性和定量检测结果有很好的一致性.病毒复制水平上升在肝损伤和肝病进展中可能起重要作用.     

输血后丙型肝炎患者中TT病毒的检测报告

目的：TTV是一种与输血后肝炎相关的病毒。本实验检测TTV在输血后丙型肝炎患者中的分布情况。材料：20例有明确输血史、Anti-HCV和HCV RNA均为阳性的输血后丙型肝炎患者血清。方法；Anci—HCV检测采用Abbott试剂，HCV RNA检测采用上海希格尔公司试剂盒。TTV检测采用nested PCR方法，试剂由厦门大学国家肿瘤重点实验室提供。结果：20例血清中检测到1例阳性，TTV—DNA扩增片段为199bp，Anti-HCV及HCV RNA为阳性，HAV、HBV、HEV标志均为阴性。结论；中国输血后丙型肝炎患者中有TTV DNA存在，TTV是否是致肝炎病毒有待进一步研究。     

High frequencies of HGV and TTV infections in blood donors in Hangzhou

AIM: To determine the frequencies of HGV and TTV infections in blood donors in Hangzhou. METHODS: RT-nested PCR for HGV RNA detection and semi-nested PCR for TTV DNA detection in the sera from 203 blood donors, and nucleotide sequence analysis were performed. RESULTS: Thirty-two (15.8%) and 30 (14.8%) of the 203 serum samples were positive for HGV RNA and TTV DNA, respectively. And 5 (2.5%) of the 203 serum samples were detectable for both HGV RNA and TTV DNA. Homology of the nucleotide sequences of HGV RT-nested PCR products and TTV semi-nested PCR products from 3 serum samples compared with the reported HGV and TTV sequences was 89.36%, 87.94%, 88.65% and 63.51%, 65.77% and 67.12%, respectively. CONCLUSION: The infection rates of HGV and/or TTV in blood donors are relatively high, and to establish HGV and TTV examinations to screen blood donors is needed for transfusion security. The genomic heterogeneity of TTV or HGV is present in the isolates from different areas.     

The epidemiology of TT virus (TTV) infection in a hepatitis C and B virus hyperendemic area of southern Taiwan

TT virus (TTV) is a newly isolated DNA virus from the serum of a patient with posttransfusion hepatitis of unknown etiology in 1997. To evaluate the clinical and molecular characteristics of TT virus (TTV) in a hepatitis C virus (HCV) and B (HBV) hyperendemic area (Masago), 200 residents were enrolled in the study. The sera were tested for alanine aminotransferase (ALT), HCV RNA and GB virus C/Hepatitis G virus (HGV) RNA, TTV DNA, HBsAg, anti-HCV and antibodies to HGV E2-protein (anti-E2). TTV DNA was positive in 99 of the 200 sera with a prevalence rate of 49.5%. The prevalence of HBsAg, anti-HCV, HCV RNA, HGV RNA, anti-E2 and HGV exposure (defined as positive for serum HGV RNA and/or anti-E2) was 38.9%, 69.5%, 64.5%, 17.0%, 25.5% and 39.5%, respectively. Neither clinical nor virological factors were associated with TTV viremia. The rate of ALT abnormality was significantly elevated in HCV RNA-positive (34.9%) than -negative (7.0%) residents (p < 0.001). HCV viremia was the only factor significantly associated with ALT elevation by multiple logistic regression (odds ratio: 6.96; 95% C.I.: 2.60-18.7). We concluded that in this HCV/HBV hyperendemic area, the prevalence of TTV DNA was high. No significant clinical factor was observed to be associated with TTV infection. TTV infection is not related to abnormal ALT levels and ALT abnormality was mainly attributable to HCV but not TTV, HBV or HGV infection.     

上海地区血液透析患者与供血者中输血传播病毒DNA检测及部分核苷酸序列分析

目的　了解上海地区暴露于血及血制品的血透患者中输血传播病毒（ＴＴＶ）感染率。方法　采用套式ＰＣＲ技术,检测了 ６例血透患者和 ４９例供血员血清中 ＴＴＶ ＤＮＡ,并对其中各 １例 ＰＣＲ产物（２７２ｂｐ）测］３。结果血透患者ＴＴＶ ＤＮＡ的检出率为 ３２．８％（２０／６１）,供血员的检出率为 ２４． ５％（１２／４９）。 ２０例 ＴＴＶＤＮＡ阳性血透患者中,６例为单纯ＴＴＶ感染,６例为ＴＴＶ、ＨＣＶ及ＨＧＶ重叠感染,４例为ＴＴＶ、ＨＣＶ和４例为ＴＴＶ、ＨＧＶ重叠感染。在所有ＴＴＶ感染者中,仅发现１例血清ＡＬＴ升高,该病例为ＴＴＶ、ＨＣＶ及ＨＧＶ重叠感染。对ＰＣＲ阳性扩增产物２７２ｂｐ测序结果显示,上海株（ＳＨＰ、ＳＨＤ）核苷酸的同源性为９９．６％,与深圳株、２株日本株核着酸的同源性分别为９７．４％、９８．７％和９８．７％,表明ＴＴＶ上海株与深圳株及日本株（Ｎ２２、Ｇ１ａ）属同一亚型,首次证实了上海地区的ＴＴＶ感染。结论ＴＴＶ感染可经血传播。其致病性较弱,对ＴＴＶ的研究尚属开始,ＴＴＶ的病原学、流行病学及临床意义等问题还有待进一步探索和阐明。     

TT virus and hepatitis G virus infections in Korean blood donors and patients with chronic liver disease

AIM: To determine the prevalences of TTV and HGV infections among blood donors and patients with chronic liver disease in Korea, to investigate the association of TTV and HGV infections with blood transfusion, and to assess the correlation between TTV and HGV viremia and hepatic damage. METHODS: A total of 391 serum samples were examined in this study. Samples were obtained from healthy blood donors (n=110), hepatitis B surface antigen (HBsAg)-positive donors (n=112), anti-hepatitis C virus (anti-HCV)-positive donors (n=69), patients with type B chronic liver disease (n=81), and patients with type C chronic liver disease (n=19). TTV DNA was detected using the hemi-nested PCR. HGV RNA was tested using RT-PCR. A history of blood transfusion and serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were also determined. RESULTS: TTV DNA was detected in 8.2 % of healthy blood donors, 16.1 % of HBsAg-positive donors, 20.3 % of anti-HCV-positive donors, 21.0 % of patients with type B chronic liver disease, and 21.1 % of patients with type C chronic liver disease. HGV RNA was detected in 1.8 % of healthy blood donors, 1.8 % of HBsAg-positive donors, 17.4 % of anti-HCV-positive donors, 13.6 % of patients with type B chronic liver disease, and 10.5 % of patients with type C chronic liver disease. The prevalence of TTV and HGV infections in HBV- or HCV-positive donors and patients was significantly higher than in healthy blood donors (P<0.05), except for the detection rate of HGV in HBsAg-positive donors which was the same as for healthy donors. There was a history of transfusion in 66.7 % of TTV DNA-positive patients and 76.9 % of HGV RNA-positive patients (P<0.05). No significant increase in serum ALT and AST was detected in the TTV- or HGV-positive donors and patients. CONCLUSION: TTV and HGV infections are more frequently found in donors and patients infected with HBV or HCV than in healthy blood donors. However, there is no significant association between TTV or HGV infections and liver injury.     

Prevalence and persistence of a novel DNA TT virus (TTV) infection in Japanese haemophiliacs

To clarify the clinical implication of a newly discovered 'TT virus (TTV)', we assayed TTV DNA in sera from 50 haemophiliacs by a seminested-PCR. TTV DNA was detected in 75% (35/50), which was a much higher prevalence than for HBV (HBc-Ab), HCV RNA, or HGV RNA. In particular, TTV DNA was found in 44.4% (4/8) of patients who had been treated only with virally inactivated factor VIII concentrates. Elevated ALT levels were observed in patients with HCV RNA and TTV DNA; however, the elevation in TTV DNA was obtained from patients co-infected with HCV RNA (62.9%, 22/35). There was no significant difference in ALT levels between TTV DNA-positive and DNA-negative in patients without HCV RNA. 85.3% (35/41) of TTV DNA-positive sera in 1990 were again positive for TTV DNA in 1995. These findings suggest that many haemophiliacs have been infected with TTV. Although TTV infection was not associated with serum ALT elevation, persistent TTV infection may contribute to cryptogenic hepatic failure in haemophiliacs.     

High rate of TTV infection in multitransfused patients with pediatric malignancy and hematological disorders

The prevalence of transfusion-transmitted virus (TTV) infection has not been known in patients suffering from pediatric malignancies and hematological disorders who receive blood transfusion and/or blood products during treatment. Blood samples were taken from 75 patients. TTV infection was identified when TTV DNA was detected in serum by a polymerase chain reaction (PCR) assay. Hepatitis C virus (HCV) and hepatitis G virus (HGV) RNA were also assayed by PCR. TTV DNA was detected in 38 of 75 patients (51%). In 4 of 38 patients, the amount of blood transfused was less than 3 units. By time since last transfusion, TTV DNA was detected in 12 of 35 patients after more than 4 years, 12 of 21 between 1 and 4 years, and 14 of 19 within 1 year. Six patients had mixed infection of TTV and HCV, and 12 patients had mixed infection of TTV and HGV. Three different kinds of virus were found simultaneously in serum from 3 patients. Eight out of 75 patients showed abnormal levels of alanine aminotransferase (ALT) (>40 IU/liter), and 3 of them had TTV DNA. All patients who had TTV DNA and elevated ALT levels also were positive for HCV RNA and HGV RNA. The prevalence of TTV infection is high in patients with pediatric malignancies and hematological disorders after episodes of blood transfusion. Transfusion is one of the most important risk factors for TTV infection regardless of the amount of blood transfused.     

Investigation of HGVand TTVinfection in sera and saliva from non—hepatitis patients with oral diseases

AIM：To determine the frequencies of HGVand TTVinfections in serum and saliva samples of non-hepatitis patients with oral diseases in Hangzhou area,and to understand the correlation between detected results of HGVRNAand/orTTVDNAin sera and in saliva from the same patients.METHODS:RT-nested PCRfor HGVRNAdetection and semi-nestedPCRfor TTVDNAdetection were performed in the serum and saliva samples from226non-hepatits patients with oral diseases,and nucleotide sequence analysis.RESULTS:Twenty-seven(11.9%)and21(9.3%)of the 226serum samples were only positive for HGVRNAand TTVDNA,respectively,10(4.4%)and9(3.9%)of the 226saliva samples were only positive for HGVNA and TTVDNA,respectively.And7(3.1%)ofthe serum samples and2(0.9%)of the saliva samples showed the positive amplification results for bothHGVRNAand TTVDNA.12saliva samples from the 34patients(35.3%)withHGVor HGV/TTVviremia and 11saliva samples from the 28patients(39.3%)with TTV or HGV/TTVviremia were HGVRNAdetectable,respctively,including two patients positive for bothHGVRNAand TTVDNAin serum and saliva samples.No saliva samples from the 226patients were found to be HGVRNAor TTVDNAdetectable while their serum samples were negative for HGVorTTV.Homologies of the nucleotide sequences of HGVand TTVamplification products from the serum and saliva samples of the two patients compared with the reported sequences were 88.65&#177;91.49%and65.32-66.67%,respectively,In comparison with the nucleotide sequences of amplification products between serun and fromsaliva sample from any one of the two patients,the homlogies were98.58%and 99.29%for HGV,and were98.65%and98.20%forTTV,respectively.CONCLUSION:Relatively high carrying rates of HGVand/orTTVin the sera of non-hepatitis patients with oral diseases in Hangzhou area are demonstrated.Parts of the carriers are HGVand/orTTVpositive in their saliva.The results of this study indicate that dentists may be one of the populations with high risk for HGVand/orTTVinfection.and by way of saliva HGV and TTVmay be transmitted among individuals.     

Transmission of and liver injury by TT virus in patients on maintenance hemodialysis

To study the prevalence and clinical significance of TT virus (TTV) infection in hemodialysis patients, we tested for TTV DNA in serum, using the nested polymerase chain reaction. The prevalence of TTV DNA in 352 hemodialysis patients was 32%, significantly higher than that in 50 healthy blood donors (12%). The prevalence increased with age (P = 0.0098); it was 20% (22/110) in patients aged less than 49 years, 37% (69/188) in those aged 50–69 years, and 41% (22/54) in those aged over 70 years. Other clinical features and the prevalence of other hepatitis viral markers tested did not differ between patients with TTV DNA and those without it. The detection rate of hepatitis C virus (HCV) and hepatitis G virus (HGV) viremias increased with duration of hemodialysis and with the number of blood transfusion units, but the prevalence of TTV viremia did not. Twenty-nine of 91 patients followed for 5 years were initially positive for TTV DNA. Of these 29 patients, 17 (59%) carried this viremia for at least 5 years. Fourteen of the 62 patients (23%) who were initially negative for TTV DNA acquired TTV viremia. Serum alanine aminotransferase (ALT) levels were elevated in patients with HCV viremia but not in patients with HGV or TTV viremia. However, the mean ALT level in patients with all three viremias (HCV, HGV, and TTV) was significantly higher than that in patients with one or two of the viremias. More than 30% of the hemodialysis patients had TTV viremia and the carrier state was maintained for years. The hemodialysis procedures, including blood transfusion, did not seem to be crucial for the transmission of TTV. The pathogenic effects of TTV on hepatitis appear to be limited. (Received July 21, 1998; accepted Sept. 25, 1998)     

TT virus infection in patients with hepatitis C: frequency, persistence, and sequence heterogeneity.

TT virus (TTV) was recently identified in the serum of a patient with hepatitis. The role of TTV in liver disease has not been established. Three polymerase chain reaction (PCR) protocols were used to detect TTV DNA in sera of persons infected with hepatitis C virus (HCV) and in blood donors. Sera from 11.5% of HCV-infected patients and 7.7% of blood donors were positive by protocols 1 or 2. In contrast, 48.7% and 57.7% of sera, respectively, were positive when tested by protocol 3. There was no difference in the severity of hepatitis in persons coinfected with TTV and HCV when compared with those infected with HCV alone, regardless of which TTV PCR protocol was used. TTV DNA persisted in serum samples taken up to 6 years apart in individual patients. Sequence analysis indicated that most viral sequences were distinct between patients, and there was evidence of genetic heterogeneity and viral evolution within individuals.