Preparation of a hydrolyzed yeast ß-glucan chromium(III) complex and evaluation of its hypoglycemic activity and sub-acute toxicity.

Yeast ß-glucan (BYG) possesses extremely low solubility that has limited its applications. In this study, we hydrolyzed BYG using snail enzyme to obtain hydrolyzed yeast ß-glucan (HBYG) with desirable water solubility and hypoglycemic activity. On the basis of HBYG, HBYG­chromium(III) complex (HBYG-Cr) was synthesized. The molecular weight of the complex was 4.41 × 104 Da, and the content of trivalent chromium was 8.95 %. The hydroxyl groups of HBYG participated in the coordination and formed the chromium complex. The space conformations of HBYG exhibited remarkable changes after complex formation. HBYG-Cr existed mainly in an amorphous state and presented good dispersibility, and the surface was uneven. The hypoglycemic activity of HBYG-Cr was studied in db/db and C57 mice. The results showed that HBYG-Cr had good hypoglycemic activity. Histopathological studies demonstrated that the liver, kidney, pancreas, and skeletal muscle in the treatment group were significantly improved compared with those in the diabetic model group. The sub-acute toxicity of HBYG-Cr was studied in KM mice and the results indicated that the complex did not cause adverse reactions or toxic side effects. This study broadened the application of yeast ß-glucan and provided an important reference for the development of hypoglycemic functional foods and drugs.

[Efficacy and safety of telbivudine treatment to block mother-to-child transmission of hepatitis B virus: a meta-analysis].

OBJECTIVE: To evaluate the efficacy and safety of telbivudine treatment in pregnant patients with chronic hepatitis B to block mother-to-child transmission of hepatitis B virus (HBV). METHODS: Medline and the Chinese Biomedical Literature Database were searched for studies of HBV, mother-to-child transmission, and telbivudine. Of the 68 potentially relevant publications, eight randomized controlled trials (RCTs) conformed to the inclusion and exclusion criteria. Following data extraction, a meta-analysis was carried out with RevMan5.1 software. RESULTS: Seven of the eight RCTs were in Chinese, and the remaining study was in English but carried out at a Chinese site. The RCTs comprised a total of 678 subjects, including 352 cases and 326 controls. Infants born to telbivudine-treated mothers had a significantly lower rate of HBsAg positivity and HBV DNA positivity at birth than the control group of infants (odds ratio (OR) = 0.27, 95% confidence interval (CI): 0.17, 0.43, P less than 0.00001; OR = 0.14, 95% CI: 0.06, 0.32, P less than 0.00001). Infants born to telbivudine-treated mothers also had significantly lower rates of mother-to-child transmitted HBV at 6 months (OR = 0.06, 95% CI: 0.02, 0.22, P less than 0.00001; OR = 0.05, 95% CI: 0.01, 0.25, P = 0.0003) and 12 months (OR = 0.13, 95% CI: 0.03, 0.56, P = 0.007; OR = 0.08, 95% CI: 0.02, 0.37, P = 0.001) after birth. The pre-telbivudine treatment levels of HBV DNA were not significantly different between pregnant women in the telbivudine-treated group and the control group (OR = 0.12, 95% CI: 0.00, 0.24, P = 0.04), but the HBV DNA levels were significantly lower in the telbivudine-treated group of pregnant women prior to delivery (OR = -3.92, 95% CI: -4.90, -2.95, P less than 0.00001). There was no evidence of telbivudine treatment being associated with more adverse side effects or complications during pregnancy or in the infant (OR = 1.72, 95% CI: 0.68, 4.38, P = 0.25; OR=0.69, 95% CI: 0.04, 11.24, P = 0.80). CONCLUSION: Telbivudine treatment effectively and safely prevents mother-to-child transmission of HBV from chronically infected mothers with a high degree of infectivity late in pregnancy.

[Construction of MyD88-Pseudomonas aeruginosa epitope DNA vaccine and its expression in eukaryotic cells].

AIM: To construct the MyD88-Pseudomonas aeruginosa epitope vaccine and study its expression in eukaryotic cells. METHODS: To design and synthesize an epigene containing three B cell epitopes of OprF and one foreign "promiscuous" T cell epitope by overlapping extension PCR. tPA signal encoding sequence was amplified by PCR and then it was inserted into the 5' terminus of the epigene to construct tPA-OprF. tPA-OprF and MyD88 were cloned into the expression vector pIRES and the recombinant plasmid pIRES-tPAOprF-MyD88 was constructed. The recombinant plasmid was transfected into COS-7 cells by electroporation. The expression protein of tPA-OprF and MyD88 was detected by Western blot. RESULTS: The recombinant plasmid pIRES-tPA-OprF-MyD88 was successfully constructed. Western blot analysis indicated the tPA-OprF fusion protein was expressed in supertanant of COS-7 cells and MyD88 protein in COS-7 cells. CONCLUSION: The recombinant plasmid pIRES-tPA-OprF-MyD88 has been successfully constructed and tPA-OprF and MyD88 protein can be highly expressed in transfected cells. It may be used as a potential candidate of preventive vaccine of pseudomonas aeruginosa.