[PreC/C gene-targeting RNA interference suppresses hepatitis B virus replication and expression in human hepatoma cells].

Objective: To explore the antiviral efficacy of small interfering RNAs (siRNAs)/shRNA targeting preC/C of HBV in human hepatoma cells Huh-7 and HepG2.2.15 cells.

[C gene-targeting short hairpin RNA suppresses the replication and expression of hepatitis B virus in BHK-21 cells].

Objective: The vaccines currently developed against infectious diseases fail to induce effective antiviral immune responses to control an abrupt outbreak of viral diseases epidemic in a short space of time. Hence there is an urgent need to develop emergency vaccines capable of producing prophylactic effects against infectious diseases. RNA interference (RNAi) is a mechanism that inhibits gene expression by causing the degradation of specific RNA molecules or hindering the transcription of specific genes.

[Transfection of siRNA expressing plasmids targeting S gene inhibits replication and expression of hepatitis B virus in hepatic cancer cells].

Objective: To study the inhibitive effects of transfection of siRNA expressing plasmids targeting S gene, one of the 4 open reading frames of hepatitis B virus (HBV), on the replication and expression of HBV.

Methods: Two plasmids expressing 2 siRNAs targeting S gene, one of the 4 open reading frames of HBV (S1 and S2) and one nonspecific plasmid (siRNA-S3), as negative control, with the length of 21 nt heterologous to the HBV/U95551 genome were constructed, and then transfected into the hepatic cancer cells of the line HepG2.2.

A peptide of foot-and-mouth disease virus serotype Asia1 generating a neutralizing antibody response, and an immunostimulatory peptide.

The epitopes of the capsid of foot-and-mouth disease virus (FMDV) play important roles in the construction of highly immunogenic subunit vaccines. However few epitopes have been found for FMDV serotype Asia1. In this study we screened for epitopes of the VP1 and VP2 proteins of FMDV serotype Asia1 isolate, YNBS/58.

[Expression in Escherichia coli of hepatitis B virus genes from minority nationality patients in Yunnan province with chronic hepatitis B and their antigenicity].

Objective: To investigate the expression in Escherichia coli (E. coli) of hepatitis B virus (HBV) genes from minority nationality patients in Yunnan province with chronic hepatitis B (CHB) and their antigenicity.

Methods: Peripheral blood samples were collected from 25 minority nationality patients with CHB in Yunnan province.

[Identification of hepatitis B virus genotypes in patients with chronic hepatitis B from different nationalities in ethnic minority areas in Yunnan Province, China].

Objective: To determine whether there is evolutionary difference in hepatitis B virus (HBV) genotypes among the patients with chronic hepatitis B (CHB) of different nationalities and its clinical significance.

Methods: Peripheral blood samples were collected from 50 CHB patients, 25 of diverse nationalities and 25 of Han nationality from the ethnic minority regions in Yunnan Province, China, The HBV preS2/S (pre S2/S) and C genes were amplified by PCR. The PCR products were inserted into the vector pBluescriptIISK (pBS).

Recombinant bivalent vaccine against foot-and-mouth disease virus serotype O/A infection in guinea pig.

In this study, two DNA fragments encoding amino acid (141-160)-(21-140)-(141-160) of the VP1 of FMDV (foot-and-mouth disease virus) serotype O and (138-160)-(21-40)-(138-160) of the serotype A FMDV were chemically synthesized. These two tandem-repeat fragments were ligated and transfected into prokaryotic expression vector pTrcHis A to construct pTH-O-A. The other vector called pTH-O-scIgG-A was constructed similarly only that the two tandem-repeat DNA fragments were linked by the bovine-IgG heavy chain coding sequence.