Protective effect of pyrroloquinoline quinone on damage of hippocampal neurons induced by NMDA in rats / 中国康复理论与实践

@# ObjectiveTo investigate the protective effect of pyrroloquinoline quinone (PQQ) on damage of hippocampal neurons induced by NMDA.MethodsHippocampal neurons were cultured in vitro and NMDA was used to induce neurotoxicity 8 d after, while PQQ were used or not before. The metamorphosis of hippocampal neurons was observed under the microscope. Intracellular calcium levels was measured by confocal laser microscopy. ResultsThe intracellular Ca2+ level increased rapidly after exposure to 0.1 mmol/L NMDA and resulted in neuronal necrosis and apoptosis. Otherwise, pretreatment of the cultured neurons with PQQ reduced the increase of the intracellular Ca2+ level and the neuronal necrosis or apoptosis induced by NMDA.ConclusionPQQ can protect hippocampal neurons from damage induced by NMDA.

The change of HBeAg expression in patients infected hepatitis B virus with pre-C signal enzyme cleavage site mutation / 中华检验医学杂志

Objective To study HBeAg change in patients infected hepatitis B virus(HBV) with pre-C signal enzyme cleavage site mutation. Methods Mutation in pre-C signal enzyme cleavage site was detected by PCR-RFLP. The PreC/C gene with mutation was amplified by PCR and was cloned to EB viral eukarotic expression vector. Then transfect the vector with wild type or mutant PreC/C gene to HepG2 cell. SEAP reporter system was used to monitor the efficiency of transfection. HBeAg and its precursor in the supernatant and HepG2 cell were detected by ELISA and Western blot. Results HBeAg was positive in the supernatant of wild type and negative control in T1862 vaniant by ELISA. In HepG2 cell transfected with wild type, three proteins were detected by Western blot, they were HBeAg(17 000) and two HBeAg precursor(22 000 and 25 000). And in HepG2 cell transfected T1862 vaniant, only two HBeAg precursor was detected. The precursor in cells transfected withT1862 vaniant were significantly stronger than cells transfected with wild type. Conclusion Mutation in pre-C signal enzyme cleavage site may affect the decoration of HBeAg, which may cause great of HBeAg precursor locating in cells and lead to HBeAg negative in serum of patients infected with HBV.