Background: The Hepadnaviridae family is composed of small hepatotropic DNA viruses, divided into two main genera: Avihepadnavirus, which infects birds;and Orthohepadnavirus, which infects mammals. The human hepatitis...Background: The Hepadnaviridae family is composed of small hepatotropic DNA viruses, divided into two main genera: Avihepadnavirus, which infects birds;and Orthohepadnavirus, which infects mammals. The human hepatitis B virus (HBV) is a member of the latter family and contains a relaxed circular double-stranded DNA genome of approximately 3 kb, and the objective of this study is to evaluate the genetic diversity of the genome of the Hepadnaviridae family. Materials and Methods: For this study, we evaluated the 26 NCBI reference sequences of the Hepadnaviridae family. Result: The two main genera, Avihepadnavirus and Orthohepadnavirus, show low similarity between them. The Orthohepadnavirus, to which HBV belongs, has two important hosts, monkeys and bats, while the genus, which infects humans, has greater diversity but is similar to the viruses that infect monkeys. The Paraepadnavirus isolated from the white sucker fish and the Herpetohepadnavirus from the Tibetan frog showed strong similarity with the Avihepadnavirus found in birds. The Metahepadnavirus isolated from the bluegill fish was the Hepadnaviridae which had the greatest difference, with less than 20% similarity using CLC Sequence Viewer. Conclusion: The Hepadnaviridae genomic replication cycle involves a late reverse transcriptase (RT) step. This polymerase, however, does not have proofreading activity, resulting in genetic variability in the Hepadnaviridae family.展开更多
The present study observed the mutual benefit role of liver and pancreas in combined hepaticopan-creatic transplantation in rats. The results indicated that pancreas, when transplanted with liver, could survive for a ...The present study observed the mutual benefit role of liver and pancreas in combined hepaticopan-creatic transplantation in rats. The results indicated that pancreas, when transplanted with liver, could survive for a significant long time (13. 4±1.01 days) than it transplanted alone (9. 2±1.14 days) (P< 0. 05, t test). The interstitial rejection was mild and its rejection grade was significantly different from that of pancreas transplanted alone (P<0. 05, X2 test). The liver, when transplanted with pancreas, regenerated with strong competence and contact structure morphologically compared with liver transplanted alone. We think that pancreas could be immunologically protected against rejection and liver can be nutri-tionalized by pancreas in combined liver and pancreas transplantation.展开更多
文摘Background: The Hepadnaviridae family is composed of small hepatotropic DNA viruses, divided into two main genera: Avihepadnavirus, which infects birds;and Orthohepadnavirus, which infects mammals. The human hepatitis B virus (HBV) is a member of the latter family and contains a relaxed circular double-stranded DNA genome of approximately 3 kb, and the objective of this study is to evaluate the genetic diversity of the genome of the Hepadnaviridae family. Materials and Methods: For this study, we evaluated the 26 NCBI reference sequences of the Hepadnaviridae family. Result: The two main genera, Avihepadnavirus and Orthohepadnavirus, show low similarity between them. The Orthohepadnavirus, to which HBV belongs, has two important hosts, monkeys and bats, while the genus, which infects humans, has greater diversity but is similar to the viruses that infect monkeys. The Paraepadnavirus isolated from the white sucker fish and the Herpetohepadnavirus from the Tibetan frog showed strong similarity with the Avihepadnavirus found in birds. The Metahepadnavirus isolated from the bluegill fish was the Hepadnaviridae which had the greatest difference, with less than 20% similarity using CLC Sequence Viewer. Conclusion: The Hepadnaviridae genomic replication cycle involves a late reverse transcriptase (RT) step. This polymerase, however, does not have proofreading activity, resulting in genetic variability in the Hepadnaviridae family.
文摘The present study observed the mutual benefit role of liver and pancreas in combined hepaticopan-creatic transplantation in rats. The results indicated that pancreas, when transplanted with liver, could survive for a significant long time (13. 4±1.01 days) than it transplanted alone (9. 2±1.14 days) (P< 0. 05, t test). The interstitial rejection was mild and its rejection grade was significantly different from that of pancreas transplanted alone (P<0. 05, X2 test). The liver, when transplanted with pancreas, regenerated with strong competence and contact structure morphologically compared with liver transplanted alone. We think that pancreas could be immunologically protected against rejection and liver can be nutri-tionalized by pancreas in combined liver and pancreas transplantation.
