[Summary] To investigate the association of rs2282679 A/C polymorphism in vitamin D binding protein gene with vitamin D deficiency in 1 216 participants.A standardized questionnaire was applied to collect information on alcohol consumption,smoking habits,and use of medications.Serum 25-hydroxyvitamin D [25 (OH) D] was determined by radioimmunoassay.Vitamin D binding protein genotypes were determined by SNaPshot method.1216participants included 457 women(37.6％),478 (39.3％)with vitamin D deficiency [25 (OH) D＜50 nmol/L],and 386 (31.7％) overweight/obese participants.The frequencies of rs2282679 CC,AC,and AA genotypes were 8.7％,41.0％,and 50.3％,respectively.The distributions of genotypes and alleles differed significantly between participants with sufficient vitamin D and those with vitamin D deficiency (P ＜ 0.05).There were significant differences in the serum levels of 25 (OH) D between three genotypes before and after being adjusted for covariates (P＜0.01).AA had a 22％ (OR =0.78,95％ CI 0.65-0.93,P =0.006) lowered risk of vitamin D deficiency compared with the whole studied population.Compared with CC genotype,AA had a 36％ lowered risk of vitamin D deficiency(OR =0.64,95 ％ CI 0.42-0.98,P =0.006),while there was no significant difference between AC and CC genotypes(OR=0.87,95％ CI0.57-1.34,P=0.53).In conclusion,the vitamin D binding protein rs2282679A/C polymorphism was significantly associated with serum level of 25 (OH) D and risk of vitamin D deficiency.

BACKGROUND:Toxic cytarabine is often used to prepare highly purified neurons in experimental studies addressing central nervous system diseases. However, the intervention time of cytarabine is little reported. OBJECTIVE:To determine the optimal intervention time of cytarabine(final concentration 10μmol/L) in primary culture of rat cortical neurons. METHODS:Rat primary cortical neurons were cultured in Neurobasal+B27 medium, and 10μmol/L cytarabine were added at 12, 24, 36 and 48 hours after culture, respectively. Half of the medium were changed every 48 hours. The morphology of neurons was observed under inverted microscope at 7 days. The purity and differentiation of neurons maturity were identified by immunocytochemistry method of neuron specific enolization enzyme staining. Morphometric analysis for all neuron-specific enolase positive cells was performed by Multifunction Computer Image Analysis System. RESULTS AND CONCLUSION:After addition of cytarabine at 24 hours of culture, the purity of neurons was more than 90%, well-differentiated cortical neurons accounted for 89.00%, and the area of neuronal body was the largest with the longest synapses. There were more neuron cells with transparent cytoplasm, and large nucleus. The cell body had good refraction and strong stereo sense. The neurons with 3-4 synapses and 3-4 bifurcates formed a good network structure. These results illustrate that although it willbe beneficial for the purity of neurons to add cytarabine early in neuron culture process, it will make obvious effect on neuronal differentiation. The highly purified and well-grown cerebral cortical neurons will be obtained after cultured in neurolbasal medium, which cytarabine is added to at 24 hours of culture.