应用聚合酶链反应检测南京地区TT病毒感染

目的：了解南京地区TT病毒感染情况。方法：采用巢式PCR方法检测血清标本中TTV－DNA。结果：163例病毒性肝炎患者血清标本中,TTV－DNA总检出率为21.5％（35／163）,其中甲型肝炎13.3％（4／30）,乙型肝炎21.3％（16／75）,丙型肝炎20.0％（3／15）,戊型肝炎5.3％（1／19）,非甲－庚型肝炎45.8％（11／24）。结论：南京地区存在TTV感染,TTV是导致非甲－庚型肝炎的重要病因,TTV可能存在非血源性传播途径。     

400例献血员TT病毒检测与分析

目的 探讨靖江地区献血员中TT病毒（TTV）感染情况。方法 用套式－聚合酶链反应（nested-PCR)对400名职业献血员作TT病毒检测。结果 发现阳性36名，阳性率为9％。从中随机取10名作序列分析，并与日本报道的N22克隆核苷酸序列相比较，发现同源性为89％－99．5％。结论 TTV检测对保障输血安全至为重要。     

36例非甲、乙、丙、丁、戊型病毒性肝炎患者的血清病原学检测

目的：对非甲－戊型病毒性肝炎患者的血清病原学进行探讨。方法：用酶联免疫吸附法（ELISA）和PCR法检测36例非甲－戊型病毒性肝炎患者血清的病毒标记物。结果：庚型肝炎病毒抗体（抗－HGV）阳性率为19％,庚型肝炎病毒核糖核酸（HGVRNA）阳性率为36％;抗巨细胞病毒免疫球蛋白M（抗－CMVIgM)和抗EB病毒免疫球蛋白M（抗－EBVIgM)均阳性;输血后肝炎相关病毒DNA（TTVDNA）阳性率为31％,TTVDNA阳性者的PCR产物与日本株N22的同源性为95％。结论：TTV、TGV感染在乌鲁木对地区病毒性肝炎患者中占有相当比例,并同时存在不明致病因子感染,应当引起方式工作者的重视。     

肝炎患者中TT病毒DNA及其IgG抗体的检测

目的：了解肝炎患中TTV的感染情况，方法：应用Nested-PCR对137份甲－庚型肝炎、31份非甲－庚型肝炎及104份献血员进行TTV DNA检测，同时用ELISA法检测抗TTVIgG。结果：TTV基因检出率分别为甲－庚型肝炎20．44％，非甲－庚型肝炎29．03％，献血员13．46％，抗TTVIgG检出率分别为甲－庚型肝炎27．74％，非甲－庚型肝炎35．48％，献血员14．42％；甲－庚型肝炎、非甲－庚型肝炎与献血组相比TTV DNA及抗TTV IgG均存在显性差异（P＜0．01）。结论：肝病中存在TTV感染，TTV存在健康携带状态。     

新疆阿克苏地区输血传播病毒检测分析及克隆测序

为了解输血传播病毒（TTV）在阿克苏地区城乡、维汉两民族及献血者中的感染情况和基因序列，为今后在我区开展TTV检测、防治、流行病学词查及科研积累资料．我们对我区城乡长住的汉族和维吾尔族共1044人进行了抗-TTV检测，并用巢式PCR法进行TTV—DNA检测，最后对TTV—DNA的目的基因片段分子克隆、测序，再与H本N22株进行同源性比较。     

新疆地区献血者HGV和TTV感染的流行病学分析

目的：研究分析庚型肝炎病毒（HV）和输血传播病毒（TTV）在新疆地区献血中的感染状况，方法：采用酶联免疫吸附试验（ELISA）法检测抗－HGV IgG、逆转录聚合酶链反应（RT－PCR）技术检测HGV RNA，聚合酶链反应（PCR）技术检测TTV RNA，对1997年维吾尔族献血和321名汉族献血的血清标本进行了检测分析。结果：518名研究对象中抗－HBV IgG的阳性检险率为6．5％（34／518）。维吾尔族和汉族血抗－HBV IgG阳性率分别为11．2％（22／197）和3．7％（12／321），X^2=10．9，P＜0．005，维吾尔族有偿献血，无偿献血抗－HBV IgG阳性率分别为13．5％（21／156）、2．4％（1／41），X^2＝4．0，P＜0．05；汉族有偿献血、无偿献血抗－HGV IgG阳性率分别为7．5％（8／106）和1．9％（4／215），X^2＝6．4，P＜0．05，维吾尔族和汉族抗－HGV阳性献血HGV RNA阳性率分别为77．3％（17／22）和66．7％（8／12），X^2=0．5，P＞0．05。维吾尔族和汉族献血TTV DNA阳性率分别为25．7％（9／35）和13．0％（6／46），X^2＝2．1，P＞0．05，抗－HGV阳性和阴性献血中TTV DNA阳性率分别为35．3％（12／34）和14．0％（7／50），X^2=5．2，P＜0．05。结论：新疆地区存在HGV和TTV感染，有偿献血为HGV感染的高危人群，抗－HGV阳性献血有更高的TTV DNA检出率，这种重叠感染的机制有待进一步研究分析。     

血清中输血传播病毒检测及临床意义的探讨

目的 研究血清中输血传播病毒（TTV）抗体的检测及其临床意义。方法采用间接ELISA法检测88例患者及20例献血员血清中TTV抗体。结果88例患者中11例血液透析患者、35例乙型肝炎患者、26例丙型肝炎患者、4例庚型肝炎患者和12例非甲-庚型肝炎患者以及20例献血员TTV抗体阳性率分别为27．3％、20．0％、7．8％、0．0％、25．0％与5．0％。结论 在正常人群中TTV健康携带者较为常见；血液透析患者与非甲-庚型肝炎患者是TTV感染的高危人群；乙型及丙型肝炎患者常重叠TTV感染。     

115例抗-HEV E2-IgM、IgG阳性感染者HEV RNA检测与基因分型研究

目的对戊型肝炎暴发人群中115例抗-HEV E2-IgM、IgG阳性感染者进行病毒RNA检测和基因分型研究，探讨其临床意义。方法对收集的暴发人群中115例抗．HEV E2-IgM、IgG均阳性人员血清和23例戊型肝炎患者粪便标本，采用通用引物进行逆转录-酶链聚合反应（RT-PCR）扩增戊型肝炎病毒Ⅰ、Ⅳ型基因片段，并进行测序和同源进化分析。结果从被检血清中扩增出8例戊型肝炎病毒阳性RNA基因片段，阳性毒株之间核苷酸同源性在97．3％～100％之间，进化树分析提示阳性毒株与戊型肝炎病毒基因Ⅳ型距离最近，与日本株和中国原型株的同源性分别为93．3％～95．3％和86．7％～87．3％；粪便标本中未能检测到戊型肝炎病毒RNA。结论本次急性戊型肝炎暴发流行由戊型肝炎病毒基因型Ⅳ型导致，暴发毒株与日本株有更近的亲缘关系；高灵敏度引物和取样时机是提高戊型肝炎病毒RNA检出率的前提。     

北美供血者、暴发型肝衰竭和隐性肝硬化患者的TTV感染

不明原因的肝硬化仍占美国漫性肝病的5％。在暴发性肝衰竭患者中,24％的成人和47％的儿童患者尚无确切原因。1997年Nishizawa等报告了一种新的DNA病毒与未明的原因（非甲一度型）肝炎患者转氨酶增高有关,这种病毒被命名为TT病毒（TTV）。TTV是一个无包膜的单链DNA病毒,全长3739个碱基。由于TTV感染先前未在日本以外有报道,作者曾探查过北美是否有TTV感染,并进而分析了TTV在几组肝病患者的流行状况。方法按照梅欧临床和基础研究评审委员会所订方案将TTV感染人群分为5组。参照（Jkamoto等报告的文献合成了2对引物（NG059和N…     

献血者中TT病毒检测及其致病性探讨

目的　探讨TT病毒 (TTV)在输血过程中的传播及其致病性。方法　常规酚 氯仿法抽提血清病毒DNA ,设计位于TTVORF1保守区的两对引物 ,套式PCR扩增病毒DNA。ELISA检测血清HBsAg、抗 HAV、抗 HCV和抗 HIV。结果　健康献血者血清中TTV DNA检出率为 4 3 1 % (96 / 2 2 3)。受血者输血TTV DNA阳性血后 2周 ,血清TTV DNA转阳率为 6 3 6 % (1 4 / 2 2 )。 8周血清TTC DNA阳性率仍为 4 6 4 % (1 0 / 2 2 ) ,其中两对献血者和受血者之间血清TTV DNA同源性达 1 0 0 %。上述 2 2名受血者输血 2周后血清ALT、TB和DB正常 ,血清HBsAg、抗 HAV、抗 HCV和抗 HIV均阴性。随访其中 5例至 8周 ,无肝炎症状及体征 ,血清肝功能正常。结论　TTV可通过血液传播 ,但无明显致病性     

Detection of TT virus DNA in patients with non-A to G liver diseases]

A novel single-stranded DNA virus, TT virus(TTV), has been reported recently. We detected TTV viral sequences by polymerase chain reaction using primers derived from nucleotide sequences of ORF1 and the 5' noncoding region of ORF2. Using primers of the 5' noncoding region, TTV DNA was detected in 21 of 25(84%) healthy individuals, suggesting that most TTV strains detected by these primers are almost harmless. In contrast, using primers of ORF1, which detect genotype 1a TTV that was reported to be a causative agent of posttransfusion hepatitis, TTV DNA was detected in only 3 of 25 healthy subjects and 3 of 27 acute and 9 of 72(12%) chronic non-A to G hepatitis patients. Whether these TTV strains actually cause hepatitis remains to be determined.     

Incidence of TT virus infection in patients with non-A to G liver disease]

The sera of patients with liver disease associated with non-A to G hepatitis were examined for the presence of TTV DNA. These patients included 18 cases with AH, 8 cases with CH, 6 cases with LC, 4 cases with HCC, and 36 cases with blood donors. The detection of TTV DNA was performed as described by Nishizawa et al. TTV DNA was detected in 60.0%, 62.5%, 66%, 50%, 28% of the patients with AH, CH, LC and HCC, respectively. Among the patients with AH, the aminotransferases and total bilirubin values were lower in the TTV DNA-positive than -negative patients. Among the patients with chronic liver disease, however, there were no differences in the blood chemistry results between the TTV DNA-positive and -negative patients. The histological study of the liver tissues from a TTV positive patient with CH showed no evidence of necro-inflammatory reaction, although there was evidence of irregular regeneration in the TTV DNA-positive a patient. These results suggest that TTV infection may modify the pathological condition of the liver disease.     

TT virus infection does not affect the clinical profiles of patients with hepatitis B and C in Yanbian City,China

China is an area of high endemicity for viral hepatitis, and the molecular epidemiological investigation of TT virus (TTV) infection is of interest. In the present study, we investigated the epidemiology, clinical significance and molecular characteristics of TTV infection in patients with chronic hepatitis B and C in Yanbian City, China. Serum samples obtained from 74 patients with hepatitis B and hepatitis C who visited Yanbian Hospital, located in northeast China, were analyzed in this study. The study group included 22 cases of chronic hepatitis B (B-CH), 17 cases of liver cirrhosis B (B-LC), 7 cases of hepatocellular carcinoma (B-HCC), 16 cases of chronic hepatitis C (C-CH), 11 cases of liver cirrhosis C (C-LC) and 1 case of hepatocellular carcinoma (C-HCC). Detection of TTV DNA was performed as described by Nishizawa et al. The second-round PCR products from 7 subjects were sequenced, followed by investigation of nucleotide homology and phylogenetic analysis. TTV DNA was present in 18.2, 5.9, 28.6, 6.3, 9.1 and 0% of the patients with B-CH, B-LC, B-HCC, C-CH, C-LC and C-HCC, respectively. The highest prevalence of TTV infection was seen in the groups aged 40-50 and over 60 years. There was no significant correlation between the presence of TTV DNA and the clinical parameters in patients with hepatitis B and C. The various isolates showed 97.9-100% with isolates reported previously from Japan and 98.4-100% with isolates reported previously from China. Nucleotide sequence analysis revealed that the Yanbian isolates could be classified in the same group as the Japan and China isolates. We concluded that chronic coinfection with TTV did not affect the serological features of chronic hepatitis B and C in China, as found in Tokyo, Japan.     

输血传播病毒感染与丙型肝炎病毒感染的相互影响

目的了解输血传播病毒(TTV)与丙型肝炎病毒(HCV)重叠感染的发生率,探讨TTV感染与HCV感染的相互影响。方法采用酶联免疫吸附试验(ELISA)法检测血清中人类免疫缺陷病毒(HIV)、乙型肝炎病毒(HBV)、HCV、庚型肝炎病毒(HGV)及TTV标志物,应用巢式聚合酶链反应(n-PCR)技术检测血清TTV DNA,用速率法或终点法检测血清肝功能指标,用放射免疫法检测血清肝纤维化指标,用超声诊断仪检查肝胆脾形态及动态指标;应用SPSS 11.0软件分析比较肝功能检测结果、肝纤维化指标检测结果及肝脾形态和动态指标改变的差异。结果TTV/HCV重叠感染占TTV感染的69.6%(39/56),占HCV感染的61.9%(39/63)。TTV、HCV感染与TTV/HCV重叠感染肝功能检测结果差异有统计学意义(P<0.05);肝纤维化指标检测结果差异有统计学意义(P<0.05)。结论TTV/HCV重叠感染存在很高的发生率,感染者肝损程度较重,临床进程加快,有肝纤维化趋势。     

TT virus infection in patients with hepatocellular carcinoma associated with non-A to G hepatitis: histopathological study]

To study if TTV infection is involved in the development of hepatocellular carcinoma (HCC), we tested the sera of 19 patients with HCC associated with non-A to G hepatitis for the presence of serum TTV DNA, and compared the blood chemistry values and liver histology of the patients in the TTV DNA-positive and -negative groups. Detection of TTV DNA was performed described as Nishizawa, et al method. TTV DNA was detected in the sera of 47.4%. There were no significant differences in the blood chemistry results and other tests between the TTV-positive and -negative patients. Histological examination of the non-tumor regions of the liver showed that there were no significant differences in the number of areas and characteristics of the necro-inflammatory reactions, the degree of staging and irregular regeneration of hepatocyte between the two groups. These results suggest that the development of HCC in patients with non-A to G hepatitis is not associated with TTV infection.     

Prevalence of TT virus in serum and peripheral mononuclear cells from a CAPD population.

BACKGROUND: A novel virus named TT virus (TTV) has been isolated recently from patients with posttransfusional hepatitis of unknown etiology. The prevalence of TTV in several groups at risk has been reported, however, there is no information about the prevalence of TTV in patients on continuous ambulatory peritoneal dialysis (CAPD) without blood transfusions or hemodialysis antecedents. OBJECTIVE: To study the incidence of TTV in serum and peripheral blood mononuclear cells (PBMC) of CAPD patients. DESIGN: TTV DNA was detected by polymerase chain reaction, using primers from the open reading frames (ORF) 1 and 2, in serum and PBMC from 22 CAPD patients who had not received blood transfusions or hemodialysis therapy prior to CAPD. As controls, sera from 20 patients with chronic viral hepatitis (10 with HBV and 10 with HCV) and 20 healthy donors were included in the study. RESULTS: TTV DNA was detected in the serum of 5 of 22 (22.7%) CAPD patients with both sets of primers. Four of the 5 (80%) patients with TTV DNA in their serum were TTV positive in their PBMC with primers from ORF1 and ORF2. Five of 20 (25%) patients with chronic viral hepatitis (2 patients with HBV and 3 with HCV) and 4 of 20 (20%) healthy donors were TTV DNA positive in serum. No relation was found between TTV infection and the underlying kidney disease, previous surgery, and abnormal alanine aminotransferase levels. CONCLUSION: We have found a relatively high prevalence of TTV that is similar to that found in healthy donors and in patients with chronic viral hepatitis.     

深圳市一般人群HGV和TTV感染的研究

为探讨深圳市一般人群中HGV和TTV感染状况及其影响因素。方法采用随机抽样法选取研究对象 ,对HGV感染的检测先用ELISA法检测样本中的抗 -HGV ,对其中阳性样本再用反转录PCR(RT -PCR)进行检测 ;TTVDNA则采用巢式PCR方法检测。结果表明 ,深圳市一般人群中HGVRNA和TTVDNA阳性率分别为 2 33%和 14 77% ,男女阳性率HGVRNA为 2.45%和2.20% ,TTVDNA阳性率为 17.86%和 12.0%。年龄组间HGVRNA及TTVDNA阳性率差异均无显著性 ;单因素和Logistic回归分析未显示肝炎病史、近期手术史、注射史、拔牙史及乙型肝炎疫苗接种史等因素与HGV及TTV感染有关 ;HBsAg、抗 -HBS和抗 -HBc与HGV及TTV感染无统计学意义。不同职业人群中HGVRNA阳性率以中学生和教师较高 ;TTVDNA阳性率则以税务干部和教师高于其他人群 ,因此证明 ,深圳市一般人群中HGV和TTV感染率较高 ,但其流行因素有待进一步研究。     

TT virus(TTV) infection in patients with acute hepatitis]

A novel DNA virus, TT virus(TTV), has been reported in patients with posttransfusion hepatitis of unknown etiology. However association between TTV and acute hepatitis has not been shown. We investigated the prevalence of TTV in acute hepatitis. TTV-positive rates in acute hepatitis A, B, C, cytomegalovirus infection, Epstein-Barr virus infection, and acute hepatitis of unknown etiology were 15.3%, 21.8%, 60.0%, 0%, 10.0%, 22.6%, respectively. There were no significant differences in TTV prevalence between each etiology and healthy blood donors(20.8%). Clinical data were similar between patients with or without TTV. In this study we could not find any difference in the prevalence of TTV between acute hepatitis with known etiologies and that with unknown etiology. TTV did not affect the clinical features of acute hepatitis with known etiologies.     

TTV materno-infantile infection--a study on the TTV frequency in Japanese pregnant women and the natural history of TTV mother-to-infant infection]

We preliminarily describe the frequency of TTV in Japanese pregnant women, non-parenteral, postnatal materno-infantile transmission of TTV, and 2 cases in which infantile development of the TTV carrier-state seemed to have occurred by vertical infection. The sera of 85 hepatitis B, C and G-positive and 36 non-pathological pregnant Japanese women were screened for the presence of TTV DNA with a use of semi-nested PCR. The positive rates were 25.9 and 27.8%, respectively. No significant differences were gained between these two groups. Twenty-one infants were born to the TTV carrier women. Of them, 9 infants (42.9%) sero-converted to TTV DNA-positive after their age of 4 months. Among the infants who were breast-fed, the positive sero-conversion rate of TTV DNA tended to increase as the length of the breast feeding period increased. Serum AST/ALT levels stayed within normal upper limits in the 9 infants. This study indicates the frequent, and furthermore, certain possibility of non-parenteral (i.e., via breast milk), postnatal vertical infection of TTV.