The prevalence of TT virus (TTV) DNA among 244 healthy individuals in 23 cities on 12 islands in Indonesia was determined by polymerase chain reaction (PCR) with primers derived from the coding region (N22), which can...
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The prevalence of TT virus (TTV) DNA among 244 healthy individuals in 23 cities on 12 islands in Indonesia was determined by polymerase chain reaction (PCR) with primers derived from the coding region (N22), which can detect TTV DNA of genotypes 1-6. By N22 PCR, TTV DNA was detected in 102 (42%) individuals. The amplified PCR products were molecularly cloned and three clones each were subjected to sequence analysis. Three hundred one (98%) of the 306 TTV clones were classified into genotype 1, 2 or 3, and none into genotypes 4-6. The remaining five clones from two individuals (Kt-08 and Kt-10) on Kutai, Kalimantan Island, differed by > 30% from known TTV isolates of all 21 genotypes and were tentatively classified into genotypes 22 and 23, respectively. Using primers specific for the new TTV genotype 22 or 23, TTV genotype 22 was detected significantly more frequently in Kutai than in the other 22 cities (41% vs. 5%, P < 0.001). TTV genotype 23 was restricted to Kutai (17% vs. 0%, P < 0.001), suggesting the indigenous nature of this genotype. Analysis of two TTV isolates (Kt-08F and Kt-10F) demonstrated the extreme diversity of TTV and the preservation of the genomic organization and transcription profile.
Isolates of the newly characterized, single-stranded DNA virus TTV, have been tentatively classified into four major phylogenetic groups and at least 28 genotypes. Four Japanese isolates, designated as YONBAN viruses,...
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Isolates of the newly characterized, single-stranded DNA virus TTV, have been tentatively classified into four major phylogenetic groups and at least 28 genotypes. Four Japanese isolates, designated as YONBAN viruses, belong to the fourth group and to genotype 21. In this study, a genotype 21-specific PCR assay was standardized. With this assay, 48/184 (26%) serum samples and 76/167 (46%) saliva samples, collected from unselected ambulatory patients (aged 2 to 82) of a Brazilian public hospital, were positive. A total of 110 (66%) patients had TTV genotype 21 DNA in serum, saliva, or both fluids. Furthermore, 18/37 (49%) serum samples, collected from Indians belonging to three ethnic groups of the Western Brazilian Amazon, were also positive. Nucleotide sequences (253 bases at the 3' end of the non-coding region of the genome) were determined, that derived from 25 individuals, i.e. 17 patients and eight Indians. Phylogenetic analysis showed that three: isolates from Indians of a :particular ethnic group formed a separate subgroup within genotype 21. Among non-Indians, a clustering of strains was: observed according to their country of origin (Japan or Brazil), with all 17 sequences derived from Brazilian patients located in a unique subgroup.
To investigate vertical transmission of TT virus, TTV-DNA was looked for in serum samples taken from 22 mothers and their 22 infants at birth and during nine months of follow-up. Sixteen mothers at delivery and six in...
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To investigate vertical transmission of TT virus, TTV-DNA was looked for in serum samples taken from 22 mothers and their 22 infants at birth and during nine months of follow-up. Sixteen mothers at delivery and six infants within nine months of age had TTV-DNA detected by the amplification of the non coding (NC) region. Two of these newborns had positive viremia at birth. Sequence analysis of the NC region of five mother-infant pairs revealed that the TTV strains detected at three and six months of age in two of the infants were closely related to that of their mothers, whereas two that became TTV-DNA positive at three moths had a different nucleotide sequence from that of their mothers. One of the two infants with detectable viremia at birth also had a different nucleotide sequence from her mother. These findings suggest that both in utero and perinatal transmission of TT virus may occur, and that the strain detected in the infants was not invariably dominant in the mothers at delivery.
Objective-To determine the prevalence of GB virus-C (GBV-C) RNA and TT virus (TTV) DNA in patients with systemic sclerosis (SSc), rheumatoid arthritis (RA), and osteoarthritis (OA) as well as to compare the autoantibo...
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Objective-To determine the prevalence of GB virus-C (GBV-C) RNA and TT virus (TTV) DNA in patients with systemic sclerosis (SSc), rheumatoid arthritis (RA), and osteoarthritis (OA) as well as to compare the autoantibody pattern in patients with SSc with and without evidence of viral infection. Patients and methods-The study included 168 patients (84 SSc, 41 RA, and 43 OA) diagnosed according to the American College of Rheumatology criteria and 122 volunteer blood donors. The presence of GBV-C RNA and TTV DNA in serum was assessed by nested reverse transcriptase-polymerase chain reaction (RT-PCR) and semi-nested PCR, respectively. Autoantibodies in patients with SSc were determined by enzyme linked immunosorbent assay (ELISA) and Hep-2 immunofluorescence. Results-TTV-DNA was detected in 10/84 (12%) patients with SSc, 9/41 (22%) patients with RA, 3/43 (7%) patients with OA, and 16/122 (13%) blood donors. GBV-C RNA was present in 4/84 (5%) patients with SSc, 2/43 (5%) patients with OA, and 5/122 (4%) blood donors. No patient with RA was positive for GBV-C RNA. One patient with SSc and one patient with OA showed a double infection with GBV-C and TTV. 74/84 (88%) patients with SSc were positive for at least one autoantibody species tested: 18/84 (21%) showed anti-centromeric autoantibodies, 55/84 (66%) a speckled (36/84 (43%) fine, 19/84 (23%) coarse), and 20/84 (24%) a homogeneous nuclear Hep-2 pattern, and 21/84 (25%) had antinucleolar autoantibodies. Anti-Scl-70 antibodies were found in 31/84 (37%) and anti-RNP antibodies in 5/84 (6%) patients with SSc. No differences in the autoantibody pattern in patients with SSc with or without viral infection could be detected. Conclusion-The prevalence of GBV-C RNA and TTV DNA in serum samples from patients with SSc, RA, and OA was low and comparable with that in blood donors. A continuing infection with TTV and or GBV-C was not associated with a significant change in the autoantibody pattern in patients with SSc. These data pro
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