Objective To study the prevalence of the occult hepatitis B virus infection (OBI) and the mutation of amino acid sequence in S gene of voluntary blood donors in AnHui/FuJian/Jiang Xi Province Blood centers.Methods Serologic testing for anti-HBc by ELISA was performed with HBsAg-HBV DNA+ samples from voluntary blood donors in three province blood centers.The S region of HBV of those samples was amplified and sequenced.The genotype and mutation of amino acid sequence were analyzed by MEGA6.Results 21 in 123046 blood donors from AnHui Province blood center were HBsAgHBV DNA+,the prevalence of OBI was 0.017％,and 76.2％ of these-OBI samples was positive in anti-HBc,S region was amplified by nest-PCR in 15 OBI samples,8 of them were B genotype,the others were C genotype.39 samples of 51 OBI blood donors from FuJian Province blood center were anti-HBc positive,16 samples of those OBI donors were amplified S region,14 were B genotype,the others were C genotype.There are 30 OBI blood donors from JiangXi Province blood center,24 of them were anti-HBc positive,S region was amplified in 4 samples,1 was B genotype,the others were C genotype.Of all 35 OBI samples,26 showed amino acid mutation,which was in MHR region of S gene,especially in HBV α epitope.Conclusion The rate of prevalence of OBI in AnHui Province was 0.017％,there was also certain OBI infection in FuJian and JiangXi Province.In the OBI samples which were amplified S region,the positive rates of anti-HBc in three blood centers were 73.3％,93.8％,100％.B Genotype was the main HBV genotype.The mutation in MHR region of S gene,especially in HBV α epitope,may be one of the reasons to cause OBI.

Objective To investigate the possible effect of citrate on electrolyte metabolism in healthy people with different genders and races and provide a reference for the possible clinical interventions.Methods A cross over,placebo-controlled study was conducted in 22 age-matched Chinese(11 males and 11 females)and 10 male Caucasian volunteers after informed consents were obtained.Volunteers received of saline solution,separated by a wash-out period of two to three weeks.Serial blood and urine samples were collected during the observation period and analyzed for the selective biochemical parameters.Results Comparable basal levels of serum albumin[male(43.05±1.81)g/L vs female(42.26±2.67)g/L]and serum ionized calcium[male(1.27±0.04)mmol/L vs female(1.26±0.04)mmol/L]were observed between different genders of Chinese volunteers.However,citrate intervention led to more pronounced decrease of ionized calcium level in Chinese females compared to Chinese males[-28.68%(-20.00%--35.2%)vs-23.84%(-16.53%--29.32%),t=3.19,P ＜ 0.01].There was no differences of the levels of serum inorganic phosphate[-18.81%(-3.16%--25.09%)vs-19.23%(-1.22%--32.16%),t=0.36,P＞0.05]and albumin[-0.32%(3.27%--7.60%)vs 1.88%(6.03%--9.31%),t=0.47,P＞0.05].Independent of gender,citrate intervention resulted in an increased excretion of urine calcium in Chinese volunteers[before 0.34(0.09-0.87)vs after 0.96(0.18-1.47),t=6.66,P ＜0.01].Compared to Caucasian males,Chinese males has a higher basal level of serum ionized calcium [(1.27±0.04)mmol/L vs(1.22±0.02)mmol/L,t=3.7,P ＜0.01]and larger amplitude basal rhythm in serum albumin level[-11.72%(-5.70%--14.21%)vs-1.74%(2.43%--7.68%),t=7.43,P ＜ 0.01].Application of citrate resulted in comparable changes of serum ionized calcium [-23.84%(-16.53%--29.32%)vs-21.95%(-18.31%--30.92%)],phosphate[-19.23%(4.65%--32.16%)vs-12.68%(0.68%--42.19%)],albumin[-0.32%(1.05%--7.60%)vs-1.39%(1.87%--7.26%)]and urine calcium excretion[237.70%(11.8%-935%)vs 234.37%(5.45%-504.00%)]between Chinese and Caucasian males(t=0.32,0.03,0.25 and 0.04 respectively,P＞0.05).Serum levels of magnesium were not influenced in all volunteers during two interventions.Conclusions Independent of race and gender,the invention of citrate results in comparable changes of serum magnesium,inorganic phosphate and albumin.The effect of citrate on ionized calcium levels between genders implicates a higher risk for hypocalcemic reactions in females compared to males undergoing automatic apheresis procedures.