The Prevalence of Ocular Allergy and Comorbidities in Chinese School Children in Shanghai.

OBJECTIVE: To investigate the prevalence and features of ocular allergy (OA) and comorbidities among school children in Shanghai, China. METHODS: This was a population-based cross-sectional study. Each participant completed an ISAAC-based questionnaire. The prevalence of OA symptoms, allergic rhinitis (AR) asthma, atopic dermatitis (AD), and sensitization to mites, pollen, and food was analyzed. RESULTS: A total of 724 and 942 completed questionnaires from the 7-9-year-old (young group) and the 12-14-year-old (teen group) groups were analyzed, respectively. The overall prevalence of OA symptoms was 28%. However, more young students (10.6%) reported mild to severe daily life interference caused by OA than the teens (5.7%). The young group had higher prevalence of diagnosed allergic conjunctivitis (10.2%). The overall prevalence of AR symptom, diagnosed asthma, and diagnosed AD was 40.4%, 11.6%, and 16.7%, respectively. Young children had higher prevalence of diagnosed AR and AD than the teens. There were gender associated differences in the prevalence of AR and asthma among young children, but not among the teens. The comorbidities associated with OA was also analyzed. Sensitization to mites, food, and pollen was associated with higher prevalence of allergic conditions. CONCLUSIONS: OA together with other allergic conditions affected a significant number of children in Shanghai.

Co-expression of phosphoenolpyruvate carboxykinase and nicotinic acid phosphoribosyltransferase for succinate production in engineered Escherichia coli.

Succinate is not the dominant fermentation product from xylose in wild-type Escherichia coli K12. E. coli BA 203 is a lactate dehydrogenase (ldhA), pyruvate formate lyase (pflB), and phosphoenolpyruvate (PEP)-carboxylase (ppc) deletion strain. To increase succinate accumulation and reduce byproduct formation, engineered E. coli BA204, in which ATP-forming PEP-carboxykinase (PEPCK) is overexpressed in BA203, was constructed and produced 2.17-fold higher succinate yield. To further improve the biomass and the consumption rate of xylose, nicotinic acid phosphoribosyltransferase (NAPRTase), a rate limiting enzyme in the synthesis of NAD(H), was also overexpressed. Thus, co-expression of PEPCK and NAPRTase in recombinant E. coli BA209 was investigated. In BA209, the pck gene and the pncB gene each have a trc promoter, hence, both genes are well expressed. During a 72-h anaerobic fermentation in sealed bottles, the total concentration of NAD(H) in BA209 was 1.25-fold higher than that in BA204, and the NADH/NAD+ ratio decreased from 0.28 to 0.11. During the exclusively anaerobic fermentation in a 3-L bioreactor, BA209 consumed 17.1 g L⁻¹ xylose and produced 15.5 g L⁻¹ succinate. Furthermore, anaerobic fermentation of corn stalk hydrolysate contained 30.1 g L⁻¹ xylose, 2.1 g L⁻¹ glucose and 1.5 g L⁻¹ arabinose, it produced a final succinate concentration of 17.2 g L⁻¹ with a yield of 0.94 g g⁻¹ total sugars.