【Objective】 To establish and evaluate a fluorescent antibody to membrane antigen (FAMA) method for detecting antibodies against varicella-zoster virus (VZV) based on Vero E6 cells. 【Methods】 Based on the adapted VZV-Oka-E6 strain that VZV-Oka live attenuated varicella vaccine strain grew in Vero E6 cells, Vero E6 cells were infected with VZV-Oka-E6 of three different doses (10^4.65, 10^4.95 and 10^5.25 TCID50), and the cytopathic effect was observed under a microscope to determine the optimal infection dose of VZV-Oka-E6 strain. Then the detectable sensitivity of the infected cell antigen slides prepared after fixing the infected cells with different fixatives was compared to determine the optimal fixative. As a result, the FAMA method based on Vero E6 cells for the determination of neutralizing anti-VZV has been developed. The established FAMA assay was used to detect the international standard for varicella zoster immunoglobulin with different titers to determine the sensitivity of the assay. The specificity of the assay was evaluated by detecting specific antibodies against human herpes simplex virus (HSV) type 1 and type 2. The neutralizing anti-VZV antibodies of the international standard for varicella zoster immunoglobulin were detected using VZV-infected cell antigen slides prepared in the same batch and four different batches, respectively, to determine the intra-assay repeatability and inter-assay repeatability. The international standard for varicella zoster immunoglobulin with three known titers was detected to evaluate the relative accuracy of this assay. The anti-VZV titers in 20 apheresis plasma samples were determined with the newly established FAMA test and ELISA test, respectively, and the detection results of the two methods were compared using Spearman’s correlation test. 【Results】 The optimal infection dose of the VZV-Oka-E6 strain in FAMA assay was determined to be 10^5.25 TCID50, and acetone precooled at -20℃ was used as the fixative. The FAMA test has a high sensitivity with a detecting limit of 31.25 mIU/mL for neutralizing anti-VZV titers. The negative result was observed when detecting herpes simplex virus (HSV) type 1 and 2 specific antibodies. The international standard for varicella zoster immunoglobulin was detected by VZV infected cell antigen slides prepared in the same batch and 4 different batches, with the coefficient of variation being 29.95% and 26.71%, respectively. The detection value of the international standard for varicella zoster immunoglobulin with three different titer levels was consistent with their theoretical value. The correlation coefficient of the detection results of 20 apheresis plasma samples by the FAMA test and ELISA test was 0.268. 【Conclusion】 The VZV FAMA assay has good sensitivity, specificity, repeatability, and relative accuracy in detecting neutralizing anti-VZV titers. It can be applied for detecting neutralizing anti-VZV titers in apheresis plasma samples as well as the varicella-zoster immunoglobulin (VZIG) preparations.

Objective: To understand the association between body fat distribution and calcaneal bone mineral density (BMD) in children and adolescents aged 6-16 years in Beijing. Methods: Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12-year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method from November 2017 to January 2018. A total of 15 030 students in grade 1 to 4 of primary school, grade 1 of junior and senior middle school were enrolled after excluding subjects who were not able to participate into this study due to trauma or other uncomfortable physical conditions or with missing key values or with diabetes and kidney diseases. Questionnaire survey, body composition and calcaneus bone mineral density were conducted. The relation of fat mass percentage (FMP), trunk to total fat ratio (TrTFR), trunk to limb fat ratio (TrLFR), limb to total fat ratio (LTFR) and viscera to total fat ratio (VTFR) with calcaneus BMD were assessed using the multivariate linear regression models after adjusting for possible confounding effects. The central fat distribution types were divided into 4 groups including type 1: both trunk fat and visceral fat greater than the sex-and age-specific internal P₇₅; type 2: barely trunk fat greater than P₇₅; type 3: barely visceral fat greater than P₇₅; type 4: both trunk fat and visceral fat greater than P₇₅. The central fat distribution types were included into the model in the form of dummy variables to analyze its relationship with calcaneal BMD. The sex-and age-specific z-scores of fat distribution indicators and BMD were calculated. Results: A total of 15 030 participants aged (11.4±3.3) years (50.2% boys) were involved in the analysis. In both genders, after adjusting for age, height, lean mass index, smoking, drinking, physical activity, milk intake, vitamin D and calcium supplementation, FMP, TrTFR, TrLFR and VTFR were negatively correlated with calcaneal BMD (all P value<0.05), while LTFR was positively associated with calcaneal BMD (all P values<0.05). Compared to the central fat distribution type 1, the regression coefficients (95% CI) of type 2, 3 and 4 were -0.253 (-0.418, -0.087), -0.385 (-0.567, -0.204) and -0.428 (-0.487, -0.369) in boys, respectively; the regression coefficients (95% CI) of type 3 and 4 were -0.158 (-0.301, -0.015) and -0.226 (-0.290, -0.163), respectively. Conclusion Body fat distribution and central fat distribution in children and adolescents were correlated with calcaneus bone mineral density.

Objective: To investigate the association between blood lipid and calcaneus bone mineral density (BMD) in children and adolescents aged 6-16 years in Beijing. Methods: Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12-year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method from November 2017 to January 2018. A total of 14 303 students in grade 1 to 4 of primary school, grade 1 of junior and senior middle school were enrolled after excluding subjects who were not able to participate into this study due to trauma or other uncomfortable physical conditions or with missing key values or with diabetes and kidney diseases. Questionnaire survey, blood lipid and calcaneus BMD were conducted. Multivariate linear regression was applied to quantify the association between calcaneal BMD as a dependent variable and blood lipid level as an independent variable after adjusting for the potential confounding factors. Furthermore, quantile regression was used to analyze the association between blood lipid level and different percentiles (P₂₅, P₅₀ and P₇₅) of ultrasonic velocity values of bone mineral density, and parallel test was conducted for regression coefficients of different percentiles. Results: A total of 14 303 participants aged (11.4±3.3) years (49.9% boys) were involved in the analysis. The mean age of 14 303 participants was (11.0±3.3) years. 7 142 boys accounted for 49.9%. The mean±SD of calcaneal BMD, total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), and high density lipoprotein-cholesterol (HDL-C) were (1 540.9±33.8) m/s, (3.90±0.76), (2.18±0.62), and (1.40±0.32) mmol/L, respectively. The P₅0 (P₂₅, P₇₅) of triglyceride (TG) was 0.69 (0.49-0.94) mmol/L. After the adjustment of age, height, smoking, drinking, vitamin D and calcium supplementation, dairy intake, physical activity, FMI, and MMI, a significantly inverse association (P<0.05) between TG level and calcaneus BMD was observed in both genders, which the regression coefficients (95%CI) in boys and girls were -0.064 (-0.085, -0.044) and -0.073 (-0.094, -0.053), respectively. Conclusion The level of BMD was associated with TG in boys and girls. Therefore, it is important to prevent children from hypertriglyceridemia for the bone health promotion.

Objective To understand the association between body fat distribution and calcaneal bone mineral density (BMD) in children and adolescents aged 6-16 years in Beijing. Methods Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12?year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method from November 2017 to January 2018. A total of 15 030 students in grade 1 to 4 of primary school, grade 1 of junior and senior middle school were enrolled after excluding subjects who were not able to participate into this study due to trauma or other uncomfortable physical conditions or with missing key values or with diabetes and kidney diseases. Questionnaire survey, body composition and calcaneus bone mineral density were conducted. The relation of fat mass percentage (FMP), trunk to total fat ratio (TrTFR), trunk to limb fat ratio (TrLFR), limb to total fat ratio (LTFR) and viscera to total fat ratio (VTFR) with calcaneus BMD were assessed using the multivariate linear regression models after adjusting for possible confounding effects. The central fat distribution types were divided into 4 groups including type 1: both trunk fat and visceral fat greater than the sex?and age?specific internal P75; type 2: barely trunk fat greater than P75; type 3: barely visceral fat greater than P75; type 4: both trunk fat and visceral fat greater than P75. The central fat distribution types were included into the model in the form of dummy variables to analyze its relationship with calcaneal BMD. The sex?and age?specific z?scores of fat distribution indicators and BMD were calculated. Results A total of 15 030 participants aged (11.4 ± 3.3) years (50.2% boys) were involved in the analysis. In both genders, after adjusting for age, height, lean mass index, smoking, drinking, physical activity, milk intake, vitamin D and calcium supplementation, FMP, TrTFR, TrLFR and VTFR were negatively correlated with calcaneal BMD (all P value<0.05), while LTFR was positively associated with calcaneal BMD (all P values<0.05). Compared to the central fat distribution type 1, the regression coefficients (95% CI ) of type 2, 3 and 4 were-0.253 (-0.418,-0.087),-0.385 (-0.567,-0.204) and-0.428 (-0.487, -0.369) in boys, respectively; the regression coefficients (95% CI) of type 3 and 4 were -0.158 (-0.301,-0.015) and-0.226 (-0.290,-0.163), respectively. Conclusion Body fat distribution and central fat distribution in children and adolescents were correlated with calcaneus bone mineral density.

Objective To investigate the association between blood lipid and calcaneus bone mineral density (BMD) in children and adolescents aged 6-16 years in Beijing. Methods Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12?year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method from November 2017 to January 2018. A total of 14 303 students in grade 1 to 4 of primary school, grade 1 of junior and senior middle school were enrolled after excluding subjects who were not able to participate into this study due to trauma or other uncomfortable physical conditions or with missing key values or with diabetes and kidney diseases. Questionnaire survey, blood lipid and calcaneus BMD were conducted. Multivariate linear regression was applied to quantify the association between calcaneal BMD as a dependent variable and blood lipid level as an independent variable after adjusting for the potential confounding factors. Furthermore, quantile regression was used to analyze the association between blood lipid level and different percentiles (P25, P50 and P75) of ultrasonic velocity values of bone mineral density, and parallel test was conducted for regression coefficients of different percentiles. Results A total of 14 303 participants aged (11.4 ± 3.3) years (49.9% boys) were involved in the analysis. The mean age of 14 303 participants was (11.0±3.3) years. 7 142 boys accounted for 49.9%. The mean±SD of calcaneal BMD, total cholesterol (TC), low density lipoprotein?cholesterol (LDL?C), and high density lipoprotein?cholesterol (HDL?C) were (1 540.9±33.8) m/s, (3.90±0.76), (2.18±0.62), and (1.40±0.32) mmol/L, respectively. The P50 (P25, P75) of triglyceride (TG) was 0.69 (0.49-0.94) mmol/L. After the adjustment of age, height, smoking, drinking, vitamin D and calcium supplementation, dairy intake, physical activity, FMI, and MMI, a significantly inverse association (P<0.05) between TG level and calcaneus BMD was observed in both genders, which the regression coefficients (95%CI ) in boys and girls were -0.064 (-0.085,-0.044) and-0.073 (-0.094,-0.053), respectively. Conclusion The level of BMD was associated with TG in boys and girls. Therefore, it is important to prevent children from hypertriglyceridemia for the bone health promotion.

Objective To understand the association between body fat distribution and calcaneal bone mineral density (BMD) in children and adolescents aged 6-16 years in Beijing. Methods Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12?year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method from November 2017 to January 2018. A total of 15 030 students in grade 1 to 4 of primary school, grade 1 of junior and senior middle school were enrolled after excluding subjects who were not able to participate into this study due to trauma or other uncomfortable physical conditions or with missing key values or with diabetes and kidney diseases. Questionnaire survey, body composition and calcaneus bone mineral density were conducted. The relation of fat mass percentage (FMP), trunk to total fat ratio (TrTFR), trunk to limb fat ratio (TrLFR), limb to total fat ratio (LTFR) and viscera to total fat ratio (VTFR) with calcaneus BMD were assessed using the multivariate linear regression models after adjusting for possible confounding effects. The central fat distribution types were divided into 4 groups including type 1: both trunk fat and visceral fat greater than the sex?and age?specific internal P75; type 2: barely trunk fat greater than P75; type 3: barely visceral fat greater than P75; type 4: both trunk fat and visceral fat greater than P75. The central fat distribution types were included into the model in the form of dummy variables to analyze its relationship with calcaneal BMD. The sex?and age?specific z?scores of fat distribution indicators and BMD were calculated. Results A total of 15 030 participants aged (11.4 ± 3.3) years (50.2% boys) were involved in the analysis. In both genders, after adjusting for age, height, lean mass index, smoking, drinking, physical activity, milk intake, vitamin D and calcium supplementation, FMP, TrTFR, TrLFR and VTFR were negatively correlated with calcaneal BMD (all P value<0.05), while LTFR was positively associated with calcaneal BMD (all P values<0.05). Compared to the central fat distribution type 1, the regression coefficients (95% CI ) of type 2, 3 and 4 were-0.253 (-0.418,-0.087),-0.385 (-0.567,-0.204) and-0.428 (-0.487, -0.369) in boys, respectively; the regression coefficients (95% CI) of type 3 and 4 were -0.158 (-0.301,-0.015) and-0.226 (-0.290,-0.163), respectively. Conclusion Body fat distribution and central fat distribution in children and adolescents were correlated with calcaneus bone mineral density.

Objective To investigate the association between blood lipid and calcaneus bone mineral density (BMD) in children and adolescents aged 6-16 years in Beijing. Methods Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12?year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method from November 2017 to January 2018. A total of 14 303 students in grade 1 to 4 of primary school, grade 1 of junior and senior middle school were enrolled after excluding subjects who were not able to participate into this study due to trauma or other uncomfortable physical conditions or with missing key values or with diabetes and kidney diseases. Questionnaire survey, blood lipid and calcaneus BMD were conducted. Multivariate linear regression was applied to quantify the association between calcaneal BMD as a dependent variable and blood lipid level as an independent variable after adjusting for the potential confounding factors. Furthermore, quantile regression was used to analyze the association between blood lipid level and different percentiles (P25, P50 and P75) of ultrasonic velocity values of bone mineral density, and parallel test was conducted for regression coefficients of different percentiles. Results A total of 14 303 participants aged (11.4 ± 3.3) years (49.9% boys) were involved in the analysis. The mean age of 14 303 participants was (11.0±3.3) years. 7 142 boys accounted for 49.9%. The mean±SD of calcaneal BMD, total cholesterol (TC), low density lipoprotein?cholesterol (LDL?C), and high density lipoprotein?cholesterol (HDL?C) were (1 540.9±33.8) m/s, (3.90±0.76), (2.18±0.62), and (1.40±0.32) mmol/L, respectively. The P50 (P25, P75) of triglyceride (TG) was 0.69 (0.49-0.94) mmol/L. After the adjustment of age, height, smoking, drinking, vitamin D and calcium supplementation, dairy intake, physical activity, FMI, and MMI, a significantly inverse association (P<0.05) between TG level and calcaneus BMD was observed in both genders, which the regression coefficients (95%CI ) in boys and girls were -0.064 (-0.085,-0.044) and-0.073 (-0.094,-0.053), respectively. Conclusion The level of BMD was associated with TG in boys and girls. Therefore, it is important to prevent children from hypertriglyceridemia for the bone health promotion.

Objective To examine the value of child and adolescent Korotkoff phase Ⅳ(K4)and Korotkoff phaseⅤ(K5)diastolic blood pressures for predicting subclinical cardiovascular disease(CVD)in adulthood.Methods The data was obtained from the Beijing Children Blood Pressure Study.A total of 3 198(1 700 males,53.2%)healthy children aged 6-18 years from 6 districts in Beijing in 1987 were selected.The physical examination process included measuring height,weight,and blood pressure.From a follow-up survey in 2010-2012,1 252 subjects were analyzed by the same measurements (height,weight and blood pressure)and also by using subclinical markers for vascular damage,including carotid intima-media thickness (cIMT)and carotid-femoral pulse wave velocity (cfPWV).Childhood hypertension at baseline and adulthood hypertension were diagnosed according to the China Guideline for Hypertension Prevention and Control issued in 2010.High cfPWV and high cIMT were defined in adults as having higher than age and gender-specific 75th percentile of cfPWV and cIMT.Pearson correlation coefficients were calculated to describe the association of K4 and K5 in childhood with systolic blood pressure(SBP),diastolic blood pressure(DBP),cfPWV, and cIMT in adulthood.Logistic regression was used to analyze the values of K4 and K5 to predict subclinical CVD in adulthood.Results The baseline mean value of K4 DBP was (66.4 ± 9.1)mmHg (1 mmHg＝0.133 kPa)and K5 DBP was (54.1 ± 11.1)mmHg.The prevalence rates of high-normal blood pressure were 9.4% with DBP measured by using K4,and 6.9% with DBP measured by using K5,respectively. The prevalence rates of hypertension were 11. 3% with DBP measured by using K4,and 8.4%with DBP measured by using K5.After adjustment for age and follow-up age,Pearson correlation analyses showed K4 DBP and K5 DBP in childhood were all significantly associated with adult SBP,DBP,cIMT,cfPWV in males and in females (all P＜0.05).K4 in childhood was better correlated with SBP,DBP,cIMT and cfPWV in adulthood than K5.With multi-factor logistic regression analysis,K4 was better than K5 in predicting CVD in adulthood after controlling gender and age.Further K4 was more effective in predicting cfPWV than cIMT.Conclusions There was a significant difference between K4 and K5 in Chinese children and adolescents. K4 in childhood was better correlated with CVD in adults than K5,and K4 is superior to K5 when using auscultator technique to measure DBP.

Objective: To describe the baseline characteristics of School-based Cardiovascular and Bone Health Promotion Program(SCVBH) in Beijing. Methods: Children and adolescents were selected in 30 schools (8 primary schools, 21 middle schools and one 12-year education school) from Dongcheng, Tongzhou, Fangshan and Miyun districts of Beijing by using a stratified cluster sampling method. 15 391 students in grade 1 to 4 from primary schools, grade 1 from junior and senior high schools were enrolled in the investigation with an exclusion of students who were not able to participate due to trauma or other uncomfortable physical conditions. The baseline survey including a questionnaire survey, physical examination and blood biochemical test was conducted from September 2017 to January 2018. Obesity, blood pressure, fasting blood glucose, lipid, bone density and grip were evaluated. Results: The prevalence of obesity, hypertension, hyperglycemia (impaired fasting glucose and diabetes), dyslipidemia, lower bone density were 22.3%(3 394), 14.8%(2 248), 10.4%(1 490), 20.3%(2 919) and 2.1%(316) in total respectively, and 27.2%(2 081), 16.3%(1 244), 12.8%(922), 22.2%(1 595) and 1.2%(94) for boys, 17.3%(1 313), 13.3% (1 004), 7.9%(568), 18.4%(1 324) and 2.9%(229) for girls. Boys had higher prevalence of obesity, hypertension, hyperglycemia, and dyslipidemia and lower prevalence of low bone density than girls (all P values <0.05) The mean of body mass index, systolic blood pressure, fasting plasma glucose and grip of boys were significantly higher than that of girls (all P values <0.05).The mean of body mass index, systolic blood pressure, fasting plasma glucose and grip of boys were significantly higher than that of girls (all P values <0.05), the mean of fat mass percentage, total cholesterol, triglyceride, high density lipoprotein-cholesterol and low density lipoprotein-cholesterol of boys were significantly lower than those of girls (all P values <0.05). Conclusion The prevalence of risk factors of chronic cardiovascular disease was high and the low bone density was appearing in children and adolescents in this study. The promotion of cardiovascular and bone health should be implemented in children and adolescents.

Objective To evaluate the sensitivity and specificity of CA242/CA72‐4 ratio in diagnosing early colorectal carcino‐ma .Methods Totally 87 blood specimens of colorectal carcinoma(CRC) were collected .The Chemiluminescence method was adopt‐ed to detect the levels of CA242 and CA72‐4 .Then the receiver‐operating characteristic (ROC) curve was used to analyze the sensi‐tivity and specificity of CA242/CA72 4 ratio in the diagnosis of CRC .Results Among 87 cases of suspected CRC ,56 cases (64 .37% )were eventually diagnosed as CRC ,31 cases (35 .63% ) were excluded from CRC ;the CA242 and CA72‐4 levels and CA242/CA72‐4 ratios in the CRC group were higher than those in the non‐CRC group ,the differences were statistically significant (P<0 .05) ,moreover the CA242/CA72‐4 ratio was more significant(P=0 .013) .The areas under curve (AUC) of CA242 ,CA72‐4 and CA242/CA72‐4 ratio were 0 .754 ,0 .621 and 0 .775 respectively ,in which CA72‐4 had no significant correlation with the early CRC ,while CA242 and CA242/CA72‐4 ratio had significant correlation with the CRC diagnosis(P=0 .013 ,0 .006) and their 95%confidence intervals (CI) were 0 .576-0 .851 and 0 .612 -0 .887;when the CA242/CA72 4 cutoff value was 2 .6(CA242=28 .6 , CA72‐4=11) ,the sensitivity for early diagnosis of CRC was 91 .32% and the specificity was 94 .57% .Conclusion The sensitivity and specificity of CA242/CA72‐4 ratio in the early diagnosis of CRC are higher than those of CA242 or CA72‐4 single index ,espe‐cially w hen the ratio is close to 2 .6 ,high attention should be paid to the possibility of CRC .