Background and purpose: Trichostatin A (TSA), an antifungal antibiotic with cytostatic and differentiating properties in mammalian cell culture, is a potent and specific inhibitor of histone deacetylase (HDAC). This study was aimed to investigate the influence of trichostatin A on the growth of human lung adenocacinoma cells in vitro, and to explore the mechanisms involved. Methods: MTT assay was employed to evaluate the inhibitory effect of TSA (0.1, 0.2,0.4 μmol/L) on the growth of human NCI-H1299 cancer cells. The cell cycle distribution and apoptotic ratio were determined by flow cytometry. The acetyl level of histone H4 after TSA treatment was detected by Western blot;the mRNA level of Bax,Bcl-2,p21 and cyelinBl was measured by Real-time PCR. Results: TSA inhibited the growth of NCI-H1299 cells in a dose-and time-dependent manner. Flow cytometry showed that the cells were blocked at G_2/M phase and cell apoptosis was increased compared to the control. TSA significantly increased the acetyl level of histone H4, induced p21 and Bax expression, and inhibited the expression of cyclin BI and Bcl-2. Conclusion: TSA inhibits the growth of lung cancer cells in vitro through inducing cell apoptosis and cell cycle arrest, which might be related to its regulatory effects on the acetyl blot of histone and the expression of p21, Bax, Bcl-2 and cyclinBl.

Objective: To investigate the effects of different developmental patterns on the increases of thyroid volume in children from different genders and periods, and to explore whether there is a synergistic effect on the initiation of puberty in girls, so as to provide a theoretical basis for reducing the risk of thyroid abnormalities in adulthood. Methods: A multi-stage cluster sampling was used to select a primary school in Minhang District of Shanghai, Haimen City of Jiangsu Province and Yuhuan city of Zhejiang Province. A total of 784 children aged 8-10 years old were included in "8-10 years school-aged children cohort". At the same time, a total of 491 girls aged 11-13 years were included in the "11-13 years adolescent girls cohort". The content of survey on follow-up was consistent with the one on baseline. B-ultrasonography was used to measure thyroid volume. The physical development indexes such as height (H), weight (W) and waist circumference (WC) were measured. The morning urine samples were collected and the urinary iodine content was detected. The changes of body mass index (BMI), waist circumference (WC), and thyroid volume (V) were calculated (d BMI, d WC, and d V, respectively). According to the changes of BMI and WC, the subjects were classified into four types of developmental changes, namely "B-LW-L (low d BMI, low d WC)" "B-LW-H (low d BMI, high d WC)" "B-HW-L (high d BMI, low d WC)" and "B-HW-H (high d BMI , high d WC)". Results In partial correlation analysis, thyroid volume was significantly correlated with BMI and WC at baseline or follow-up(P<0.05). The changes of thyroid volume in 8-10 years old boys were related to the changes of BMI and WC (P<0.05), the changes of thyroid volume in 8-10 year old girls were only associated with the changes of WC (P=0.03), and no association was found in 11-13 year old girls(P>0.05). In multivariate logistic regression analysis, after adjusting for baseline age, region, and differences of urinary iodine, the risk of thyroid volume increasing in B-HW-H was 2.70 times (95%CI=1.29-5.66) higher than that of B-LW-L in boys aged 8-10 years; among girls aged 11-13 years, the risk of thyroid volume increasing in B-LW-H, B-HW-L and B-HW-H were 2.46 times (95%CI=1.31-4.61), 2.16 times (95%CI=1.15-4.03) and 1.79 times (95%CI=1.07-2.99), respectively; there was no interaction between menarche age and developmental pattern on thyroid volume change trend (P=0.49). Conclusion The thyroid volume in children and adolescents increases with the development of physical development. Different developmental patterns and estrogens have certain effects on thyroid morphological changes. To avoid obesity in childhood (especially with central obesity), timely identify and effectively intervene thyroid morphological abnormalities in childhood，and to reduce the risk of thyroid diseases in adulthood.

Objective: To learn the epidemiological characteristics of coronavirus disease 2019（COVID-19）in Huzhou,so as to provide reference for prevention and control of COVID-19. Methods: All the confirmed cases of COVID-19 in Huzhou,diagnosed according to the COVID-19 Diagnosis and Treatment Plan（Sixth Version Trial）and reported from January 25 to February 7,2020,were recruited. The process of diagnosis and treatment,clinical manifestation,exposure history and close contacts were collected to analyze the epidemiological characteristics. Results: On January 25,the first confirmed cases of COVID-19 in Huzhou was reported. By February 7,totally 10 confirmed cases were reported and no asymptomatic infection was found. They were all imported,including three Wuhan residents,two with a trip to Wuhan,three with a trip to Suizhou,one with a trip to Hangzhou and one with a trip to Thailand（two Wuhan passengers on the same flight）. The ratio of male to female cases was 1∶1. The median age was 32 years old. Seven cases were found when they went to a doctor by themselves,and three cases were found during the quarantine. The main clinical manifestations were fever,dry cough and fatigue. The median time from onset to diagnosis was 3 days. By March 3,all the cases were discharged,with median course of 24 days. There were 312 close contacts,and all of them were released after 14 days of quarantine. Conclusions To prevent imported cases from outside and stop spread inside taken by Huzhou government was proved to be effective. All the COVID-19 cases in Huzhou were imported,mostly from Wuhan. No local cases were reported.

ObjectiveTo investigate the specific anti-SARS-CoV-2 antibody in adults and above after initial vaccination with inactivated COVID-19 vaccine， and determine the influencing factors. MethodsIn this study， residents aged 18 and above who had completed two doses of inactivated COVID-19 vaccine in Deqing County， Huzhou City， Zhejiang Province were included. Information such as gender， age， type of vaccine and vaccination time were collected， and serum specimens were sampled. Anti-SARS-CoV-2 receptor binding domain （RBD） antibody was quantitatively examined by enzyma-linked immunosorbent assay （ELISA） and influencing factors were determined. ResultsThe median concentration of anti-SARS-CoV-2 IgG antibody in the residents vaccinated with an inactivated booster vaccine was higher than that in those vaccinated with only two doses of COVID-19 vaccine or single dose （P<0.05）. The median concentration of IgG antibody in males was 9.73 （4.01‒23.70） RU‧mL^-1， lower than 17.76 （7.07‒49.23） RU‧mL^-1 in females （P<0.05）. The median concentration in the residents vaccinated with BBIBP-CorV （Sinopharm） was 6.53 （0.97‒13.69） RU‧mL^-1， which was lower than that in those vaccinated with CoronaVac （Sinovac） that was 17.29 （8.54‒43.73） RU‧mL^-1 （P<0.05）. The median concentration in those with BBIBP-CorV was also lower than 12 （5.45‒40.06） RU‧mL^-1 in those with heterologous booster vaccine （P<0.05）. The median concentration was 9.73 （3.83‒23.63） RU‧mL^-1 in the residents with an interval of more than 6 months from the second dose， which was lower than 14.66 （6.36‒35.98） RU‧mL^-1 in those with an interval of 3‒6 months （P<0.05）. Moreover， immune effect was better in females （χ²=16.464， P<0.05）， 18‒45 years（χ²=7.158， P<0.05）， and those vaccinated with CornaVac （χ²=49.637， P<0.05）， while decreased in those with an interval of more than 6 months from the second dose （χ²=8.447， P<0.05）. ConclusionGender， age， and type of vaccine may affect the effect of immunization. The COVID-19 vaccination shows an acceptable immunogenicity in adults； however， it declines in 6 months after vaccination. It warrants strengthening the booster vaccination to maintain the immune response.

Gaming addiction， as a main manifestation of internet addiction， is characterized by a pattern of persistent or recurrent gaming behaviors. Gaming behaviors are common among adolescents and can result in marked distress or significant impairment in personal， family， social or other important areas of functioning. Recent research on health hazards of gaming addiction is relatively scattered. This article reviews the harm of adolescent game addiction to physical and mental health.

ObjectiveTo determine the serum antibody level and risk factors in the adolescent population in a county in Zhejiang Province， following the immunization with inactivated COVID-19 vaccine， and to construct a prediction model for antibody concentration. MethodsWe conducted the study in a county in Zhejiang Province， employing a stratified cluster random sampling strategy in school children who had received the inactivated COVID-19 vaccine. Data on gender， age， type of vaccine， and time of vaccination was collected. Serum samples were also collected to test for anti-S and N IgG antibody against the SARS-CoV-2 by using chemiluminescent immunoassay （CLIA）. Risk factors were determined to construct a prediction model for antibody concentration. ResultsThe IgG antibody concentration was significantly higher in girls， those who received two doses， and those who had simply received the KX vaccine . It decreased with age and time interval between the sampling and last vaccination. The prediction model constructed by random forest regression in the study had a better model fit and predictive ability than that by the multivariable linear stepwise regression. ConclusionGender， age， vaccination dose， type of vaccine， and time of vaccination are associated with vaccination effectiveness of inactivated COVID-19 vaccines in adolescents. Prediction model could predict the antibody level in the vaccinated population， which can provide a new tool for better evaluation of vaccination effectiveness against emerging infectious diseases in future.

ObjectiveTo understand the usage of antibiotics in outpatients in a county of Zhejiang Province from 2015 to 2020， so as to provide a basis for further standardizing the clinical application of antibiotics in this region. MethodsOutpatient records and prescription records of 146 public medical institutions from 2015 to 2020 were extracted from the electronic medical record data sharing platform system of medical institutions in a county of Zhejiang Province. The utilization rates and the number of types of antibiotics used in outpatient patients were described. According to the drug anatomy， therapeutic and chemical classification system （ATC）， clinical application classification and dosage form， the use status of different types of antibiotics was observed. The annual percentage change （APC） was used to analyze the time trend of antibiotic use. Among the antibiotic prescriptions in each year， the proportions of prescriptions aimed for different use reasons and patients were compared to analyze the changes in the structures of antibiotic prescriptions. ResultsDuring 2015‒2020， a total of 2 861 438 prescriptions were issued in146 primary public medical institutions in this county， including 314 642 prescriptions for antibiotics， and the overall utilization rate of antibiotics was 11%. The utilization rate of antibiotics showed a decreased trend across the years （from 14.23% in 2015 to 7.59% in 2020，APC=-11.51%， 95%CI=-0.01%‒-21.7%， t=-12.05， P<0.001） and an obvious seasonal variation character （higher in winter and spring， lower in summer and autumn）. Cefoxitin sodium for injection was the most used antibiotic in 2015， and cefuroxime was the most used antibiotic from 2015 to 2020， respectively. The utilization rates of cephalosporins （APC=-11.06%， 95%CI=0‒-20.89%， t=-22.233， P<0.001）， quinolones （APC=-9.74%， 95%CI=0‒-18.53%， t=-7.652， P=0.002）， macrolides （APC=-17.52%， 95%CI=0‒-17.52%， t=-3.626， P=0.022） and lincoamides （APC=-49.01%， 95%CI=0‒-74%， t=-3.35， P=0.029） showed a decreasing trend across the years. There were differences in the distribution of drug use reasons （χ²=9 458.427， P<0.001）， as well as the age （χ²=5 421.709， P<0.001） and sex （χ²=245.322， P<0.001） of patients. During the observation period， 50.69% of antibiotic prescriptions were used to treat respiratory diseases， with the highest proportion of 57.67% in 2015 and the lowest proportion of 34.93% in 2020. 58.37% of patients were aged 50‒70 years， with a decreasing proportion of patients under 50 years （17.83% in 2015， 6.64% in 2020） and an increasing proportion of patients over 70 years （24.1% in 2015， 38.41% in 2020）. ConclusionThe utilization rate of antibiotics used in outpatients from primary public medical institutions in a county of Zhejiang Province shows a decreasing trend across the years， but higher than that of secondary and above hospitals in China， and also higher than that of primary medical institutions in economically-developed areas. The management and monitoring of the clinical use of antibiotics in the county should be actively strengthened.