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P Simmonds - One of the best experts on this subject based on the ideXlab platform.
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global distribution of Transfusion Transmitted Virus
The New England Journal of Medicine, 1998Co-Authors: L E Prescott, P SimmondsAbstract:To the Editor: Transfusion-Transmitted Virus has recently been identified as a potential cause of post-Transfusion non-A, non-B, non-C hepatitis.1 The Virus has a single-stranded DNA genome whose organization is similar to those of members of the Parvoviridae.2 Transient viremia due to Transfusion-Transmitted Virus was detected by the polymerase chain reaction (PCR) in three patients six to eight weeks after the Transfusion of blood components and coincided with modest elevations of alanine aminotransferase. It has been proposed that Transfusion-Transmitted Virus is the chloroform-resistant non-A, non-B agent shown to cause transient alanine aminotransferase elevations in chimpanzees.3 To understand more about the distribution . . .
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detection of a novel dna Virus tt Virus in blood donors and blood products
The Lancet, 1998Co-Authors: P Simmonds, L E Prescott, F Davidson, C Lycett, D M Macdonald, J Ellender, Geoffrey Haydon, J Gillon, L M Jarvis, Christopher A LudlamAbstract:Summary Background A newly discovered DNA Virus, Transfusion- Transmitted Virus (TTV), has been implicated as a cause of post-Transfusion hepatitis. We investigated the frequency of TTV viraemia in UK blood donors, and the extent to which TTV contaminates blood products such as factor VIII and IX clotting factors. We also investigated the possible aetiological role of TTV in cryptogenic fulminant hepatic failure (FHF). Methods We extracted DNA from plasma of blood donors and patients with FHF, and from blood products (factor VIII and IX clotting-factor concentrates, immunoglobulin preparations). We detected TTV by PCR using primers from a conserved region in the TTV genome. Findings TTV viraemia was detected in 19 (1·9%) of 1000 non-remunerated regular blood donors. Infection occurred more frequently in older donors (mean age 53 years), compared with the age prolife of donors infected with hepatitis C Virus and other parenterally-Transmitted Viruses. TTV contamination was found in ten (56%) of 18 batches of factor VIII and IX concentrate manufactured from such non- remunerated donors, and in seven (44%) of 16 batches of commercially available products. Whereas solvent or detergent treatment had little effect on the detection of TTV in factor VIII and IX by PCR, this virucidal step seemed to inactivate TTV infectivity. TTV infection was detected in four (19%) of 21 patients with FHF; in three cases, infection was detected at the onset of disease and could thus not be excluded from its aetiology. Interpretation TTV viraemia is frequent in the blood-donor population, and transmission of TTV through Transfusion of blood components may have occurred extensively. Clinical assessment of infected donors and recipients of blood and blood products, and assessment of TTV's aetiological role in hepatic and extra-hepatic disease, are urgently needed.
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global distribution of Transfusion Transmitted Virus letter
The New England Journal of Medicine, 1998Co-Authors: L E Prescott, P SimmondsAbstract:Transfusion-Transmitted Virus has recently been identified as a potential cause of post-Transfusion non-A non-B and non-C hepatitis. The Virus has a single-stranded DNA genome whose organization is similar to those of members of the Parvoviridae. Transient viremia due to Transfusion-Transmitted Virus was detected through polymerase chain reaction (PCR) in 3 patients 6-8 weeks after the Transfusion of blood components and coincided with modest elevations of alanine aminotransferase. It has been proposed that Transfusion-Transmitted Virus is the chloroform-resistant non-A non-B agent shown to cause transient alanine aminotransferase elevations in chimpanzees. The prevalence of Transfusion-Transmitted Virus infection in a wide range of geographically separated human populations and among chimpanzees in Central and West Africa was assessed. Blood samples were drawn from people in Ecuador Brazil Papua New Guinea Sudan the Gambia Nigeria the Democratic Republic of the Congo and Pakistan. High frequencies of viremia due to Transfusion-Transmitted Virus were found in most of the study populations from 16% in Pakistan to 83% in the Gambia. Transfusion-Transmitted Virus DNA sequences were also detected in 1 chimpanzee. The finding of such infection across so many study groups warrants further research.
Toshiaki Nakai - One of the best experts on this subject based on the ideXlab platform.
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Transfusion Transmitted Virus infection in china prevalence in blood donors and in patients with liver diseases
Journal of Gastroenterology and Hepatology, 1999Co-Authors: Fumio Nomura, Nobuyasu Yukimasa, Sakae Itoga, Maki Yamadaosaki, Ryo Sumazaki, Toshiaki NakaiAbstract:Background: Prevalence of Transfusion-Transmitted Virus (TTV) infection among blood donors and in patients with liver diseases in China was studied. Methods: DNA was extracted from serum and amplified by seminested polymerase chain reaction with reported primer sets from a conserved region of the TTV genome. Results: TT Virus DNA was detected in 55 of 196 blood donors (28%); 31% (40 of 127) in the north and 22% (15 of 69) in the south. TT Virus DNA was also detected in 14 of 31 patients (45%) with non-A–non-G fulminant hepatitis and in eight of 25 patients (32%) with non-A–non-G chronic hepatitis. The rate of TTV viraemia in these patients with liver disease was comparable to that in blood donors. TT Virus DNA sequencing of 12 isolates showed that the prevalence of genotype 2 was significantly higher than that reported in Japan (66.7 vs 2.6%, P < 0.001). Furthermore, genotyping assays based on restriction fragment length polymorphism were carried out on all 88 TTV DNA-positive samples. It was found that 42 isolates (47.7%) belonged to genotype 1 and 40 (45.5%) to genotype 2. It was of particular interest that the prevalence of genotype 1 in patients with non-A–non-G fulminant hepatitis was significantly higher than that in blood donors (10/14 vs 22/55, P < 0.05). Conclusions: The data indicate that TTV infection is common in China and that the pathogenic potential of TTV toward the liver (if any) may differ between genotypes.
L E Prescott - One of the best experts on this subject based on the ideXlab platform.
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global distribution of Transfusion Transmitted Virus
The New England Journal of Medicine, 1998Co-Authors: L E Prescott, P SimmondsAbstract:To the Editor: Transfusion-Transmitted Virus has recently been identified as a potential cause of post-Transfusion non-A, non-B, non-C hepatitis.1 The Virus has a single-stranded DNA genome whose organization is similar to those of members of the Parvoviridae.2 Transient viremia due to Transfusion-Transmitted Virus was detected by the polymerase chain reaction (PCR) in three patients six to eight weeks after the Transfusion of blood components and coincided with modest elevations of alanine aminotransferase. It has been proposed that Transfusion-Transmitted Virus is the chloroform-resistant non-A, non-B agent shown to cause transient alanine aminotransferase elevations in chimpanzees.3 To understand more about the distribution . . .
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detection of a novel dna Virus tt Virus in blood donors and blood products
The Lancet, 1998Co-Authors: P Simmonds, L E Prescott, F Davidson, C Lycett, D M Macdonald, J Ellender, Geoffrey Haydon, J Gillon, L M Jarvis, Christopher A LudlamAbstract:Summary Background A newly discovered DNA Virus, Transfusion- Transmitted Virus (TTV), has been implicated as a cause of post-Transfusion hepatitis. We investigated the frequency of TTV viraemia in UK blood donors, and the extent to which TTV contaminates blood products such as factor VIII and IX clotting factors. We also investigated the possible aetiological role of TTV in cryptogenic fulminant hepatic failure (FHF). Methods We extracted DNA from plasma of blood donors and patients with FHF, and from blood products (factor VIII and IX clotting-factor concentrates, immunoglobulin preparations). We detected TTV by PCR using primers from a conserved region in the TTV genome. Findings TTV viraemia was detected in 19 (1·9%) of 1000 non-remunerated regular blood donors. Infection occurred more frequently in older donors (mean age 53 years), compared with the age prolife of donors infected with hepatitis C Virus and other parenterally-Transmitted Viruses. TTV contamination was found in ten (56%) of 18 batches of factor VIII and IX concentrate manufactured from such non- remunerated donors, and in seven (44%) of 16 batches of commercially available products. Whereas solvent or detergent treatment had little effect on the detection of TTV in factor VIII and IX by PCR, this virucidal step seemed to inactivate TTV infectivity. TTV infection was detected in four (19%) of 21 patients with FHF; in three cases, infection was detected at the onset of disease and could thus not be excluded from its aetiology. Interpretation TTV viraemia is frequent in the blood-donor population, and transmission of TTV through Transfusion of blood components may have occurred extensively. Clinical assessment of infected donors and recipients of blood and blood products, and assessment of TTV's aetiological role in hepatic and extra-hepatic disease, are urgently needed.
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global distribution of Transfusion Transmitted Virus letter
The New England Journal of Medicine, 1998Co-Authors: L E Prescott, P SimmondsAbstract:Transfusion-Transmitted Virus has recently been identified as a potential cause of post-Transfusion non-A non-B and non-C hepatitis. The Virus has a single-stranded DNA genome whose organization is similar to those of members of the Parvoviridae. Transient viremia due to Transfusion-Transmitted Virus was detected through polymerase chain reaction (PCR) in 3 patients 6-8 weeks after the Transfusion of blood components and coincided with modest elevations of alanine aminotransferase. It has been proposed that Transfusion-Transmitted Virus is the chloroform-resistant non-A non-B agent shown to cause transient alanine aminotransferase elevations in chimpanzees. The prevalence of Transfusion-Transmitted Virus infection in a wide range of geographically separated human populations and among chimpanzees in Central and West Africa was assessed. Blood samples were drawn from people in Ecuador Brazil Papua New Guinea Sudan the Gambia Nigeria the Democratic Republic of the Congo and Pakistan. High frequencies of viremia due to Transfusion-Transmitted Virus were found in most of the study populations from 16% in Pakistan to 83% in the Gambia. Transfusion-Transmitted Virus DNA sequences were also detected in 1 chimpanzee. The finding of such infection across so many study groups warrants further research.
Marcello Caratozzolo - One of the best experts on this subject based on the ideXlab platform.
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prevalence and genomic variability of Transfusion Transmitted Virus in italian cryptogenic chronic liver disease and healthy blood donors
Digestive and Liver Disease, 2002Co-Authors: Marco Artini, Elisabetta Cariani, Cristiana Almerighi, Marcilla Fulco, A Rossini, L Pietropaolo, G Stivali, Giuseppe Montalto, Marcello CaratozzoloAbstract:Abstract Background. Infection with Transfusion Transmitted Virus, a new member of the Parvoviridae family, has been found in patients both with chronic and fulminant post-Transfusion cryptogenic hepatitis. Aim. To evaluate the prevalence and clinical impact of Transfusion Transmitted Virus infection in Italy. Patients and Methods. Studies were carried out on 256 patients and control subjects from three centres from Northern, Central and Southern Italy (92 nonA-nonC chronic hepatitis, 10 acute non fulminant cryptogenic hepatitis, 41 hepatitis C Virus-related chronic hepatitis and 113 blood donors). Serum Transfusion Transmitted Virus was detected by nested polymerase chain reaction using two overlapping sets of primers. Results. A total of 52 of the 92 patients (54.3%) with chronic cryptogenic liver disease and 17 of the 41 hepatitis C Virus chronic hepatitis patients (41.4%) were Transfusion Transmitted Virus-DNA positive. Transfusion Transmitted Virus co-infection in hepatitis C Virus patients was not associated with either a higher severity of liver histology or higher alanine transaminase levels or signs of cholestasis. Transfusion Transmitted Virus was found in 48 out of 113 (42.4%) blood donors. In the majority of samples, Transfusion Transmitted Virus DNA was detected with only one of the two sets of primers used. Genotyping and phylogenetic analysis performed on 21 randomly selected viral isolates showed the presence of both type 1 and type 2 Transfusion Transmitted Virus and allowed identification of two isolates with high homology to genotype 6, described, so far, mostly in Japan. Conclusions. Transfusion Transmitted Virus type 1 and 2 infection is common among blood donors and patients with liver disease in Italy. The pathogenic potential of Transfusion Transmitted Virus type 1 and 2 in nonA-nonC hepatitis patients is unlikely but further studies are needed to evaluate the epidemiological and clinical impact of other Transfusion Transmitted Virus subtypes.
Abbasali Javadi - One of the best experts on this subject based on the ideXlab platform.
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prevalence of Transfusion Transmitted Virus infection in hemodialysis patients and injection drug users compared to healthy blood donors in isfahan iran
Gastroenterology Research and Practice, 2012Co-Authors: Behrooz Ataei, Alireza Emami Naeini, Farzin Khorvash, Mohammad Reza Yazdani, Abbasali JavadiAbstract:Introduction. The pathogenicity and transmission routes of Transfusion Transmitted Virus (TTV) remain unclear. The aim of this study was to determine the prevalence of TTV in hemodialysis patients, injecting drug users (IDUs), and healthy blood donors, in Isfahan, Iran. Method. In a case-control study, a total of 108 subjects were put into three groups namely Group I, 36 hemodialysis patients; Group II, 36 IDUs; and Group III, 36 healthy blood donors as the control group. A 5 ml blood sample was collected from each subject in an EDTA-containing tube. Samples were tested for TTV DNA by means of real-time polymerase chain reaction (PCR). Results. The mean age was 38.7 ± 14.7 years. Seventy-one subjects (66%) were male. Of the108 cases, 30 (27.8%) were TTV positive and 78 (72.2%) were TTV negative. The prevalence of TTV in IDUs [21 (58%)] was significantly higher than in the other groups [group I: 6 (17 %) and group III: 3 (8%)] (P < 0.0001). Conclusion. The prevalence of TTV in IDUs is significantly higher than in both hemodialysis patients and general population in Isfahan, Iran. It seems necessary to take serious measures to reduce the risk of TTV transmission to IDUs' close contacts and health care providers.