AIM: To identify the prevalence, risk factors and manifestations of asymptomatic hepatitis C virus (HCV) infection in Egyptian children. METHODS: Children at the age of 1-9 years were screened for HCV antibodies and a...AIM: To identify the prevalence, risk factors and manifestations of asymptomatic hepatitis C virus (HCV) infection in Egyptian children. METHODS: Children at the age of 1-9 years were screened for HCV antibodies and alanine aminotransferase (ALT) levels. Every child with elevated ALT and/or detectable HCV antibodies was tested for HCV RNA by RT-PCR and compared with two negative controls for risk factors and signs and symptoms of liver disease.RESULTS: We screened 1042 children, six of them had elevated ALT, negative HCV antibody and positive RNA, likely representing acute hepatitis C cases. Fifteen children were HCV seropositive, 5 of them were HCV RNA positive. Asymptomatic HCV infection was present in 2.02% (positive results for either HCV antibodies or HCV-RNA or both). Symptoms such as diarrhea, abdominal pain, history of fatigue and school absence because of illness and risk factors such as dental care were significantly more common among HCV positive cases than among controls. None of the HCV positive children was diagnosed as having signs of advanced liver disease upon clinical or ultrasonographic examination. CONCLUSION: Asymptomatic HCV infection is detectable in 2.02% Egyptian children.展开更多
Hepatitis B virus （HBV） biosynthesis is primarily restricted to hepatocytes due to the governing of liver-enriched nuclear receptors （NRs） on viral RNA synthesis. The liver-enriched NR hepatocyte nuclear factor 4...Hepatitis B virus （HBV） biosynthesis is primarily restricted to hepatocytes due to the governing of liver-enriched nuclear receptors （NRs） on viral RNA synthesis. The liver-enriched NR hepatocyte nuclear factor 4α （HNF4α, the key regulator of genes implicated in hepatic glucose metabolism, is also a primary determinant of HBV pregenomic RNA synthesis and HBV replication. Peroxisome proliferator-activated receptor-r coactivator la （PGCla） coactivates and further enhances the effect of HNF4α on HBV biosynthesis. Here, we showed that the acetyltransferase General Control Non-repressed Protein 5 （GCN5） acetylated PGC 1 α, leading to alteration of PGC 1 α from a transcriptionally active state into an inactive state. As a result, the coactivation activity of PGCla on HBV transcription and replication was suppressed. Apparently, an acetylation site mutant of PGC 1 α （PGC 1 αR13） still had coactivation activity as GCN5 could not suppress the coactivation activity of the mutant. Moreover, a catalytically inactive acetyltransferase mutant GCN5m, due to the loss of acetylation activity, failed to inhibit the coactivation function of PGClα in HBV biosynthesis. Our results demonstrate that GCN5, through its acetyltransferase activity, inhibits PGCla-induced enhancement of HBV transcription and replication both in vitro and in vivo.展开更多
基金Supported by the Sustainable Sciences Institute, United States as part of the small grants program
文摘AIM: To identify the prevalence, risk factors and manifestations of asymptomatic hepatitis C virus (HCV) infection in Egyptian children. METHODS: Children at the age of 1-9 years were screened for HCV antibodies and alanine aminotransferase (ALT) levels. Every child with elevated ALT and/or detectable HCV antibodies was tested for HCV RNA by RT-PCR and compared with two negative controls for risk factors and signs and symptoms of liver disease.RESULTS: We screened 1042 children, six of them had elevated ALT, negative HCV antibody and positive RNA, likely representing acute hepatitis C cases. Fifteen children were HCV seropositive, 5 of them were HCV RNA positive. Asymptomatic HCV infection was present in 2.02% (positive results for either HCV antibodies or HCV-RNA or both). Symptoms such as diarrhea, abdominal pain, history of fatigue and school absence because of illness and risk factors such as dental care were significantly more common among HCV positive cases than among controls. None of the HCV positive children was diagnosed as having signs of advanced liver disease upon clinical or ultrasonographic examination. CONCLUSION: Asymptomatic HCV infection is detectable in 2.02% Egyptian children.
基金supported by grants from the National Major Science and Technology Special Projects for Infectious Diseases of China (2012ZX10004503-008, 2012ZX10001006-002,and 2012ZX10002006-002)
文摘Hepatitis B virus （HBV） biosynthesis is primarily restricted to hepatocytes due to the governing of liver-enriched nuclear receptors （NRs） on viral RNA synthesis. The liver-enriched NR hepatocyte nuclear factor 4α （HNF4α, the key regulator of genes implicated in hepatic glucose metabolism, is also a primary determinant of HBV pregenomic RNA synthesis and HBV replication. Peroxisome proliferator-activated receptor-r coactivator la （PGCla） coactivates and further enhances the effect of HNF4α on HBV biosynthesis. Here, we showed that the acetyltransferase General Control Non-repressed Protein 5 （GCN5） acetylated PGC 1 α, leading to alteration of PGC 1 α from a transcriptionally active state into an inactive state. As a result, the coactivation activity of PGCla on HBV transcription and replication was suppressed. Apparently, an acetylation site mutant of PGC 1 α （PGC 1 αR13） still had coactivation activity as GCN5 could not suppress the coactivation activity of the mutant. Moreover, a catalytically inactive acetyltransferase mutant GCN5m, due to the loss of acetylation activity, failed to inhibit the coactivation function of PGClα in HBV biosynthesis. Our results demonstrate that GCN5, through its acetyltransferase activity, inhibits PGCla-induced enhancement of HBV transcription and replication both in vitro and in vivo.
