Objective:To explore the relationship between puberty timing and cardiovascular metabolic risk factors among primary and secondary students with different genders in Beijing.Methods:Using the method of stratified cluster sampling by urban and rural areas and school sections,3 067 students from 16 primary and secondary schools in Fangshan District of Beijing were selected in October 2012,with ques-tionnaire survey,physical examination and serum laboratory testing.In this study,we controlled for con-founding factors such as school segments,current residence of the family,birth weight,feeding method,only child,highest educational level of parents,and monthly family income,and then the associations between cardiovascular metabolic risk factors and puberty timing among the primary and secondary students was analyzed by multivariate Logistic analysis.To ensure the reliability of the data,this study adopted strict quality control.Results:A total of 3 067 primary and middle school students aged 7 to 16 years were included in this study,including 1 575 boys and 1 492 girls.The prevalence of premature pu-berty was 14.73％among the boys and 12.89％among the girls,respectively.The prevalence of delayed puberty was 9.49％among the boys and 10.99％among the girls,respectively.The detection rates of central obesity,hypertension,hyperglycemia,and dyslipidemia among the primary and secondary students were 35.87％,19.95％,2.54％and 26.31％,respectively.The detection rates of 1 risk fac-tor clustering,2 risk factors clustering and more than 3 risk factors clustering were 29.21％,16.17％and 9.36％,respectively.The difference in the detection rate of cardiovascular and metabolic risk factors in different youth stages was insignificant(P＞0.05),the detection rate of risk factor aggregation of 0 was lower than that of the timely group and delayed group,and the detection rate of risk factors aggrega-tion of 2 was higher than that of the timely group(P＜0.05).After adjusting the effects of learning stage,region,birth weight,feeding patterns,one-child,family income and the parents'educational levels,multivariate Logistic regression analysis showed that,compared with the on-time puberty group,the risk of 1 risk factor clustering,2 risk factors clustering and more than 3 risk factors clustering increased by 1.94 times(95％CI=1.29-2.91),2.97 times(95％CI=1.89-4.67)and 2.02 times(95％CI=1.13-3.63)among the girls;It had not been found that the relationship between puberty timing and car-diovascular risk factor clustering among the boys(P＞0.05).Conclusion:Premature puberty is an inde-pendent risk factor for the clustering of cardiometabolic risk factors in girls,and primary prevention strate-gies should be implemented to reduce the burden of cardiovascular metabolic diseases in the population.

Objective:To investigate the compassion fatigue of medical staff working in centralized quarantine sites and its influencing factors during the COVID-19 epidemic.Methods:From September 2020 to October 2020, a cross-sectional study was conducted on 213 medical staff working in 13 quarantine centers in two districts of Shanghai. A self-made general information questionnaire, professional quality of life scale, general self-efficacy scale and perceived social support scale were used in the study.Results:The score of empathy satisfaction was 33.00(28.25, 37.75), and there were 141 cases (66.20%) with supercritical value. The score of job burnout was 26.00(21.50, 30.50), and 96 cases (45.07%) exceeded the critical value. The score of secondary traumatic stress was 25.00(20.50, 29.50), and 192 cases (90.14%) exceeded the critical value. Multivariate logistic regression analysis showed that average daily working hours, job satisfaction, self-evaluation of work pressure, general self-efficacy and perceived social support were the influencing factors of compassion fatigue among medical staff. Compared with those who worked for 0 h in the polluted area, those who worked for more than 8 h had a higher degree of compassion fatigue ( OR=7.787, 95 %CI: 1.127-53.820);compared with those who were more satisfied with their work, those who were less satisfied with their work had a higher degree of compassion fatigue ( OR=6.209,95 %CI:1.474-26.157); compared with those with no or low stress, those with high stress had higher degree of compassion fatigue ( OR=2.567, 95 %CI: 1.228-5.366); compared with those with high self-confidence, those with low self-confidence or moderate self-confidence had higher degree of compassion fatigue ( OR=13.519, 95 %CI: 3.394-53.848; OR=3.462, 95 %CI: 1.038-11.548); compared with those with high perceived social support, those with low perceived social support had higher degree of compassion fatigue ( OR=2.071, 95 %CI: 1.027-4.175) (all P<0.05). Conclusion:The status of compassion fatigue of medical staff working in the centralized quarantine sites need to be improved. We should pay more attention to the those medical staff having long daily working hours in the polluted area, those with low job satisfaction, poor self-evaluation of work pressure, poor general self-efficacy and low perceived social support.

Objective To observe the effect of phrenic nerve electrical stimulation combined with respiratory training on the pulmonary function,trunk stability and balance of stroke survivors.Methods Thirty-six stroke survivors were randomly divided into a control group and a training group,each of 28.Both groups were given routine rehabilitation treatment (including physical agent therapy and combined training of the limbs),while the training group was additionally provided with phrenic nerve electrical stimulation combined with respiratory training once a day for six weeks.Before and after the treatment,the forced vital capacity (FVC),forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF) of both groups were recorded.The Sheikh trunk control scale (TCT) was used to quantify their trunk stability,and balance was quantified using the Berg balance function scale (BBS).Results After six weeks of treatment the average FVC,FEV1 and PEF values of the training group were significantly higher than before the treatment,and significantly better than those of the control group after the treatment.Moreover,significant improvement was observed in the average TCT and BBS scores of both groups after the intervention,with the training group's average significantly higher than that of the contrcl group.Conclusion Phrenic nerve electrical stimulation combined with respiratory training can further improve the pulmonary function and balance function of stroke survivors as a supplement to routine rehabilitation treatment.Therefore,it is worth popularizing in clinical practice.

Objective To establish a stable and reliable mouse model as an alternative to the traditional model of impaired glucose tolerance induced by calorie restriction and its effect on glucose homeostasis.Methods Forty 16-week-old SPF C57BL/6J mice (half male and half female) were randomly divided into four groups by sex and the way of feeding.The mice in the ad libitum (AL) group had free access to basic diet, while the mice in the intermittent fasting (IF) group had normal diet and fasting on alternate days, with free access to water on the fasting days.The changes of body weight and blood glucose concentration in each group were monitored, and intraperitoneal glucose tolerance test and insulin tolerance test in mice were performed before and after the 12-week IF treatment.Results At 12 weeks after IF treatment, the body weight and blood glucose concentration of mice did not show significant difference.After i.p.injection of glucose, the blood glucose concentration of IF mice was less increased than the AL group, and after the insulin injection, the blood glucose concentration was more decreased.Compared to the AL group, the areas under the curve of tolerance test in the IF group were significantly decreased (P < 0.05).Conclusions After IF treatment, the mice show an enhanced sensitivity to insulin and improved glucose tolerance.This establishment method of mouse model of intermittent fasting is easy and simple, therefore, can be used as an effective alternative to traditional calorie restriction model of impaired glucose tolerance.

BACKGROUNDThe importance of polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene for the prediction of the response to fluorouracil-based adjuvant chemotherapy in gastric cancer patients remains unclear. The aim of this study is to assess the predictive value of several polymorphisms of the MTHFR gene for clinical outcomes of gastric cancer patients treated with fluorouracil-based adjuvant chemotherapy in Chinese population.

METHODSThree hundred and sixty-two Chinese patients with gastric cancer were treated with fluorouracil-based adjuvant chemotherapy. DNA samples were isolated from peripheral blood collected before treatment. The three single nucleotide polymorphisms (SNPs) (rs1801131, rs1801133, rs2274976) genotypes of the MTHFR gene were determined by matrixassisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).

RESULTSThe average response rate for chemotherapy was 46.7%. Homozygous genotypes rs2274976G/G (χ(2) = 22.7, P < 0.01) and rs1801131A/A (χ(2) = 14.3, P = 0.008) were over-represented in responsive patients. Carriers of the rs2274976A allele genotypes (G/A and A/A) and of the rs1801131C allele genotypes (A/C and C/C) were prevalent in nonresponsive patients. In the haplotype association analysis, there was a significant difference in global haplotype distribution between the groups (χ(2) = 20.69, P = 0.000 124).

CONCLUSIONSThese results suggest that polymorphisms of the MTHFR gene may be used as predictors of the response to fluorouracil-based chemotherapy for gastric cancer patients in Chinese population. Well-designed, comprehensive, and prospective studies on determining these polymorphisms of MTHFR gene as clinical markers for predicting the response to fluorouracil-based therapy in gastric cancer patients is warranted.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antimetabolites, Antineoplastic ; therapeutic use ; Asian Continental Ancestry Group ; Female ; Fluorouracil ; therapeutic use ; Humans ; Male ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Middle Aged ; Prospective Studies ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Stomach Neoplasms ; drug therapy ; enzymology ; genetics ; Young Adult

Objective To estimate any influence of strong pulsed magnetic fields on the expression of growth-related genes in human bladder cancer BIU-87 cells. Methods Human BIU-87 cells were cultured in vitro and randomly divided into a magnetic field group and a control group. Each group was further divided into 24 h, 48 h and 72 h sub-groups. The magnetic field group cells were exposed to an 8 T magnetic field pulsed at 15 Hz for 2 h every day. The control group cells also placed on the same environment, but not exposed to any strong, pulsed magnetic field. The expression of B cell lymphoma/leukemia gene-2 (Bcl-2) mRNA, Bax mRNA and caspase-3 mRNA was measured with RT-PCR, and flow cytometry was used to evaluate the expression of the Bcl-2, Bax and caspase-3 genes of the tumor cells in vitro. Results The expression of Bax mRNA and protein was significantly higher in the cells exposed to the magnetic field than in the control groups. The expression of Bcl-2 mRNA and protein was significantly less. The expression of caspase-3 mRNA and protein in the two groups showed no significant differences.Conclusions A strong, pulsed magnetic field can inhibit the growth of bladder tumor BIU-87 cells and promote their apoptosis. The mechanism is probably related with the magnetic field promoting Bax mRNA and protein expression and inhibiting Bcl-2 mRNA and protein expression.

Object To apply microwave technique to the extraction of free anthraquinones from Rheum emodi Wall. and the methods of microwave extraction and traditional extraction were comparied. Methods The orthogonal test design was used to arrange sequent experiments to test the effect of the three main factors including microwave power, particle size of herb and extraction time on the extraction efficiency of free anthraquinones and to establish optimal extraction process. A parallel test was carried out using the three different methods including the optimal extraction process, the traditional decocting method and the alcohol refluxing method. Results Particle size of herb and microwave power are the significant factors with P

Objective To analyze the property of natural polysaccharides(P) from Porphyra haitanensis T. J. Chang et B. F. Zheng and its degraded polysaccharides(P3),and to investigate their effects on proliferation of lymphocytes. Methods P3 and P were identified by IR spectra. Their effects on immunological function were studied by cell culture technique. Results P3 and P displayed significant effects on promoting the proliferation of T-lymphocytes,and had inhibitory effects on the proliferation of B-lymphocytes in a dose-dependent manner. The effects of P3 were more powerful than P. Conclusion The degraded and natural polysaccharides from Porphyra haitanensis(P3 and P) can regulate the proliferation of lymphocytes,which may be related to their molecular weights.

AIM: To optimize and establish the extraction techn ology of water-soluble polysaccharides from Ulva pertusa. TLC was employed to determine the mainly neutral sugars in the Ulvan. METHODS: The orthogonal test was employed to test the effects of th e four factors including volume of water, temperature of extraction, time of ext raction and pH of water on the yield and total carbohydrate contents of water-s oluble polysaccharides from Ulva pertusa and optimize the extraction technol ogy. Five groups of parallel tests were carried out by the optimum parameters es tablished and the sugar constituents of products were analyzed by TLC. RESULTS: Temperature of extraction and time of extraction have sign ificant effects on the extraction yield of water-soluble polysaccharides from Ulva pertu sa, but, for total carbohydrate content, only temperature of extraction was a significant factor. The mainly neutral sugars were composed of rhamnose, xylose and glucose. CONCLUSION: The optimum extraction technology was A 1B 3C 3D 3 when the yield and total carbohydrate content were considered as preferential pa rameters.