Biomedical subjects

Jin-jun Chen

Publications and source records attributed to Jin-jun Chen.

5 recordsLinked to original sources

PubMed2006

[Affects of HBV genotypes (B/C) on the levels of serum and intrahepatic HBsAg].

OBJECTIVE: To observe the effects of HBV genotypes on the level of HBsAg in serum and hepatocytes in chronic hepatitis B patients without antiviral therapy. METHODS: Seventy-six chronic hepatitis B inpatients were enrolled into this study, and liver biopsies and histologic diagnosis were performed, and serum samples were collected at the time point of liver biopsy. PCR-RFLP method was adopted to determine the genotype of hepatitis B virus and Abbott Architect HBsAg assay was used to quantify the serum HBsAg. Immunostaining for antigens in liver tissues with monoclonal antibody (for HBsAg) or polyclonal antibodies (for HBcAg) was carried out in consecutive slides. The percentages of hepatocytes for HBsAg stain, hepatocytes for HBcAg nuclear stain and hepatocytes for HBcAg cytoplasm stain were estimated in the ranges of 0 (negative), < or = 1%, 1+; 2% - 5%, 2+; 6% - 25%, 3+; 26% - 50%, 4+; and > 50%, 5+. The distributions of positive cells in slides are described as single or isolated, cluster or widespread. Surface gene was directly sequenced with the serum HBV DNA from 6 patients with genotype B and 8 with genotype C HBV infection, respectively. RESULTS: Four HBV genotypes were detected in 76 patients: 47 patients with B, 21 with C, 3 with D and 5 were infected by genotype B mixed with C HBV infection. Age, gender, serum HBV DNA level, ALT, AST or histological evaluation (grades and stages scores) were not different between the patients infected with genotype B or C HBV. The level of serum HBsAg was not significantly different between the patients infected with genotype B or C HBV, but the proportions of hepatocytes stained with HBsAg was greater in patients with C type HBV infection than B (P < 0.01). In the liver slides from the patients infected HBV genotype B, HBsAg was stained frequently in single or isolated hepatocytes (22/47), and widespread HBsAg-positive hepatocytes were often seen in the patients with C type HBV (8/21), P < 0.01. In the patients with B type HBV, serum HBsAg was positively correlated with serum HBV DNA (r = 0.674, P = 0.000), proportion of hepatocytes with HBcAg in nucleus (r = 0.534, P = 0.000) and in cytoplasm (r = 0.405, P = 0.004). In the patients with C type HBV infection, serum HBsAg had positive correlation only with serum HBV DNA (r = 0.503, P = 0.017). Proportion of HBsAg positive hepatocytes was positively correlated only with the proportion of HBcAg cytoplasm positive hepatocytes in the patients with B type HBV (r = 0.318, P = 0.029) and no correlation with serum HBsAg, HBV DNA, or proportions of hepatocytes with HBcAg in nucleus. Analysis of the first 40 amino acid sequences of surface antigen showed that variations most existed at amino acid 3, 4, 5 and 8. CONCLUSION: Proportion of HBsAg in hepatocytes is significantly greater in the patients with C type HBV than those with B type HBV. Positive correlation between serum HBsAg and viral replication was seems to be more significant in the patients with HBV genotype B infection.

Adult↗

PubMed2005

[A comparison of clinical and virological characteristics of 1686 cases of HBeAg-negative and HBeAg-positive chronic hepatitis B].

OBJECTIVE: To investigate the clinical characteristics of HBeAg-negative and HBeAg-positive chronic hepatitis B (CHB). METHODS: A total of 1686 hospitalized CHB cases were analyzed retrospectively. The serum ALT values, HBV DNA levels and hepatic inflammation and fibrosis were analyzed by their serum HBeAg status. RESULTS: Among the 1686 cases, 628 (37.3%) were HBeAg-negative and 1058 (62.7%) were HBeAg-positive. Compared with HBeAg-positive group, HBeAg-negative group had a lower serum ALT and HBV DNA levels. However, hepatic necroinflammation grading and fibrosis staging in HBeAg-negative group were more advanced than that of HBeAg-positive group. Irrespective to serum HBeAg status, patients with serum HBV DNA less than 10(5)copies/ml, had a lower hepatic necroinflammation activity. CONCLUSIONS: HBeAg-positive CHB is still the predominant form of CHB in Chinese patients. Compared with patients with low HBV replication, patients with active HBV replication had a higher hepatic necroinflammation activity. The liver histological grading and staging in HBeAg-negative CHB patients were more advanced than that in HBeAg-positive patients.

Adolescent↗

PubMed2003

[Clinical detection of polymerase gene of SARS-associated coronavirus].

OBJECTIVE: To analyze the heterogeneity of polymerase gene fragment of SARS-associated coronavirus from SARS patients, and establish a RT-PCR method for detecting SARS-associated coronavirus. METHODS: RT-PCR was performed using SARS coronavirus-specific primers to amplify the polymerase gene fragment of SARS-associated coronavirus from specimens of suspected and established SARS cases. The amplicons were cloned and sequenced. All the obtained sequences were compared with the sequence of published SARS-associated coronavirus, and alignment was proceeded with other coronavirus sequences. RESULTS: Specific amplicons can be amplified from the sputum samples, throat swab and plasma of most SARS patients, and 8 were random selected and sequenced. All of them possessed 100% homology with the published SARS-associated coronavirus sequence, while all the negative controls were RT-PCR negative. Nucleotide-sequence and amino acid-sequence alignment of the fragment BNI109 with other six known coronavirus show that the fragment BNI109 is more close to bovine coronavirus(BCV) and murine hepatitis virus(MHV). The BNI109 fragment showed 75% homology with BCV and MHV at amino acid level. CONCLUSION: The polymerase fragment BNI109 of SARS coronavirus is highly conservative and is suitable for detecting SARS-associated coronavirus using RT-PCR method.

Amino Acid Sequence↗

PubMed2003

[Antibody response of patients with severe acute respiratory syndrome (SARS) to nucleocapsid antigen of SARS-associated coronavirus].

OBJECTIVE: To assess serum antibody responses of patients with severe acute respiratory syndrome (SARS) to nucleocapsid (N) antigen of SARS-associated coronavirus. METHODS: The serum levels of IgM and IgG antibodies to N antigen were measured in 200 healthy blood donors and 13 SARS patients at different time points of acute and convalescent phases using indirect enzyme-linked immunosorbent assay (ELISA) with N fusion proteins of SARS-associated coronaviruses. RESULTS: The IgM positive critical value of 0.233 and IgG of 0.239 were selected as the threshold value for positive results that equals the product of 2.1 and the mean IgM and IgG levels of 200 healthy blood donors. In 13 patients with SARS, the antibody responses to N antigen were not detectable in the first week after the onset of symptoms. The IgM and IgG seroprotection rates were 83.3% and 66.7% respectively in the second week, both reaching 100% at the third week. IgM seroprotection rates was 61.5% in the second month, and 38.5% at third month. The IgG peaked one month after the onset and remained at high levels in the following 2 months. CONCLUSION: The antibody responses suggest that N protein of SARS is immunodominant and plays an important role in viral pathogenesis. This ELISA-based test for detecting anti- N antigen may be of significant value for SARS diagnosis.

Antibodies, Viral↗

PubMed2003

[Experimental study on constructing small-caliber artery by tissue engineering approach].

OBJECTIVE: To investigate the possibility of constructing small-caliber artery by means of tissue engineering. METHODS: Cell-PGA mixtures were made by separately seeding 1 x 10(7) smooth muscle cells and 5 x 10(6) endothelial cells isolated from neonate umbilicus onto PGA scaffold, the cell-PGA constructs were wrapped around a silicone tube before its implantation subcutaneously to nude mice and the mice were sacrificed in 2 and 6 weeks. The tissue engineered artery (TEA) were examined both grossly and immunohistochemically. RESULTS: The gross appearance of TEA was similar to that of the natural counterparts; histologic and immunohistochemical analyses of the neoformed tissues revealed a typical artery structure, including the presence of EC at the luminal surface and the presence of SMC and collagen in the wall. CONCLUSION: TEA with histology similar to natural vessel can be constructed by tissue engineering.

Animals↗