1/5. Molecular evolutionary analysis of the complete nucleotide sequence of hepatitis B virus (HBV) in a case of HBV infection acquired through a needlestick accident.To elucidate needlestick transmission of hepatitis b virus (HBV), strains isolated from 1 physician who acquired HBV infection through a needlestick accident and 3 patients with chronic hepatitis B (donor patients A, B, and C) were tested using molecular evolutionary analysis based on full-length HBV genomic sequences. Nucleotide sequences of these isolates were aligned with 55 previously reported full-length genomic sequences. Genetic distances were estimated using the 6-parameter method, and phylogenetic trees were constructed using the neighbor-joining method. Strains isolated from patient A and the recipient pair were clustered within a closer range of evolutionary distances than were strains recovered from the recipient pair and patients B and C. Furthermore, strains from patient A and the recipient were also clustered on the S gene sequences of HBV. These results demonstrated that patient A alone was the source of direct transmission to the recipient. This approach can be used to investigate the transmission route of HBV.- - - - - - - - - - ranking = 1keywords = tree (Clic here for more details about this article) |
2/5. Molecular investigation of two possible cases of accidental hiv-1 transmission in south africa.hiv-1 sequences from two possible transmission cases in south africa were examined for evidence of genetic linkage. hiv-1-seropositive blood samples were obtained from a donor and recipient within 8 months following a blood transfusion and from a healthcare worker and her patient within 10 months following a needle-stick injury. A 700-bp region in env and 550-bp region in gag were analyzed. All sequences were phylogenetically associated with hiv-1 subtype C, the predominant hiv-1 subtype in south africa. The nucleotide sequences from the blood transfusion case grouped together significantly with a bootstrap value of 100%. These samples were 98% and 100% identical in the predicted amino acid sequences of env and gag, respectively. In contrast, sequences from the needle-stick case showed only 67% and 80% amino acid identity in env and gag, respectively, and were separated on a phylogenetic tree. Molecular analysis suggested that HIV transmission occurred in the blood transfusion case but not in the case of the needle-stick injury. These data emphasize the need for molecular investigation of epidemiologically linked cases of HIV transmission.- - - - - - - - - - ranking = 1keywords = tree (Clic here for more details about this article) |
3/5. spinal cord infarction due to a self-inflicted needle stick injury.STUDY DESIGN: Case report. OBJECTIVE: To report a case of spinal cord infarction after a self-inflicted needle stick injury, following an injection of heroin into the cord. SETTING: National spinal injury unit in a Scottish University teaching hospital, Glasgow, UK. CASE REPORT: A 20-year-old male, injected street heroin accidentally into the cord through the left side of the neck, leading to sudden loss of power to all four limbs. Initial magnetic resonance imaging scans showed extensive cord oedema and follow-up scans showed signal changes within the anterior horns of the spinal cord in keeping with a cord infarct. CONCLUSION: Self-inflicted spinal cord injury with a small needle is difficult, but not impossible. Cord infarct as a result of a self-inflicted injury has not been previously reported. The mechanism of the injury resulting in cord infarction is explained by the vascular anatomy of the spinal cord circulation, and this may also explain the residual neurological status of the patient.- - - - - - - - - - ranking = 1keywords = tree (Clic here for more details about this article) |
4/5. Confirmation of hepatitis c virus transmission through needlestick accidents by molecular evolutionary analysis.To document the transmission of hepatitis c virus (HCV) through needlestick accidents, 3 health workers who acquired HCV through such accidents and their HCV donor patients were studied using molecular evolutionary analysis based on the HCV E2 region. At least six clones were sequenced from each subject. Nucleotide substitutions were estimated by the six-parameter method, and a phylogenetic tree was constructed by the neighbor-joining method. HCV isolates from the donor patient and the recipient were nested in one monophyletic cluster; this clustering was confirmed to be statistically significant by bootstrap analysis. The nucleotide divergence among the isolates from the recipient was always smaller than that from the donor, supporting the notion that the direction of transmission was from the donor to the recipient. These findings provide evidence, at a molecular evolutionary level, that HCV was transmitted through needlestick accidents.- - - - - - - - - - ranking = 1keywords = tree (Clic here for more details about this article) |
5/5. Study of needlestick accidents and hepatitis c virus infection in healthcare workers by molecular evolutionary analysis.In the five-year period between 1989 and 1993, 87 needlestick accidents occurred among healthcare workers at our hospital. Thirty-seven (43%) of these needlestick accidents involved blood contaminated with hepatitis c virus (HCV), and two of them (5.4%) led to the occurrence of hepatitis c infection. Case 1 was a 43-year-old nurse who was accidentally injured by a needle contaminated with blood from a patient who had cirrhosis and hepatocellular carcinoma due to hepatitis c. Acute hepatitis c occurred after five weeks and HCV rna was positive after eight weeks. Case 2 was a 33-year-old nurse who was injured by a needle contaminated with blood from a patient who had chronic hepatitis c. liver function was normal at 11 days after the accident. However, hepatitis c was diagnosed 21 months later after she had successfully given birth to her baby. The nucleotide sequence of the HCV E2/NS1 region was determined in the two patients and the needlestick victims, and phylogenetic trees were constructed by molecular evolutionary analysis. On the basis of these trees, transmission of HCV could be confirmed in both cases. This method of analysis may be useful for confirming the transmission of HCV even long after the event.- - - - - - - - - - ranking = 2keywords = tree (Clic here for more details about this article) |