Lower esophageal microbiota species are affected by the eradication of Helicobacter pylori infection using antibiotics.

The aim of this study was to investigate the effect of Helicobacter pylori (H. pylori) infection on the lower esophageal microbiota and the eradication of H. pylori through the use of antibiotics. Forty-five BALB/C mice were randomly divided into negative control, infection and treatment groups. The mice were sacrificed and DNA was extracted from the lower esophageal microbiota. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was performed to determine the composition of the microbiota. Quantity One® 1-D Analysis Software was used for the analysis of the DGGE profiles. The different bands from the groups were amplified with 16S rDNA V6 region primers. DNA sequencing and Basic Local Alignment Search Tool analysis were performed for the identification of the bands. H. pylori colonization led to severe ulcers in the stomachs of the mice, and these ulcers were alleviated by antibiotic treatment. The infection group had an increased number of bacterial species in the stomach compared with the control and treatment groups. DGGE fingerprinting of the lower esophagus showed that there were significant differences in the number of bands (P<0.05), diversity index and abundance among the groups (P<0.05); however, no significant differences in homogeneity were observed (P>0.05). Although the composition of flora species in the lower espohagus varied, the dominant species, and their relative contents, were similar in the control, infection and treatment groups. The present study provided a microecological basis for the understanding of the pathogenesis of lower esophageal diseases, following the eradication of H. pylori infection with antibiotics.

[Protective effect of vitamin C on protein activity in plasma during virus inactivation].

To determine whether addition of vitamin C (Vit C) to single-unit plasma could influence the efficacy of inactivating viruses and could maintain the activity of plasma proteins by methylene blue (MB)-light treatment. Vesicular stomatitis virus (VSV) Indiana strain was used as the indicating virus. Human plasma containing VSV was added with different concentrations of Vit C and final concentration 1 micromol/L MB and irradiated by fluorescence at an intensity of 40,000 lx, samples were collected at different times for detection. Cytopathic effect was used to test the effect of virus inactivation. A segment of the nucleic acid encoding capsid protein of VSV was amplified with RT-PCR. Some methods, such as the Clauss method, the one-stage method, microimmunoelectrophoresis, were used to investigate the changes of plasma components. The results showed that when the VSV plasma was added with 240 micromol/L Vit C and treated by MB-light irradiation for 60 min, the titer of VSV decreased by more than 8 lg TICD50/ml. Meanwhile, target segment amplification of VSV was also negative. The recovery rates of fibrinogen and coagulation factor VIII (FVIII: C) were 83.55% and 81.67% respectively, which had significant difference comparing with the routine MB-fluorescent light treatment. Most of plasma proteins were not affected significantly. No change in immunogenicity of these proteins was observed by using microimmunoelectrophoresis. It is concluded that virus inactivation is not influenced and plasma proteins are effectively protected by Vit C. Vit C can be used as a protector and is beneficial to improving the quality of plasma subjected to MB- photodynamic treatment.

[Optimizing cultural conditions of measles vaccine working seed lot with orthogonal experiments].

OBJECTIVE: To improve the quality of measles vaccine and find out good combination of cultural factors of measles vaccine virus seeds. METHODS: Orthogonal experiments were made to confirm optimized cultural factors. 5 lots of optimized measles vaccine working seed lot were prepared. RESULTS: The titers of the optimized vaccine seed improved significantly (> or = 0.69 +/- 0.35 LgCCID50/1.0 ml, P < 0.05), compared with 5 lots of traditional working seed lot. With these seeds we trial-prepared 5 lots of lyophilized vaccines respectively, the titer and stability met the Chinese Requirements of Biological Products. CONCLUSION: The orthogonal experiment is a kind of good method for optimizing cultural conditions of measles vaccine working seed lot. The yield and quality of measles vaccine can be improved in the optimized working seed lot with high titer and good stability.