Objective To exlpore the short-term effect of ambient fine particle matter （PM_2.5） on the incidence of acute cough. Methods A questionnaire survey on environment and health was conducted among residents in seven communities in three cities in the Pearl River Delta from November 2017 to February 2018, to investigate the occurrence of acute cough symptoms two weeks prior to the survey. Data of daily air pollution and weather of the communities were also collected simultaneously. Two-level logistic regression model was used to estimate the association between PM_2.5 and occurrence of acute cough. Results A total of 7 151 residents were surveyed, and 223（3.12%）of them had acute cough symptoms in the past two weeks. A significant short-term effect of exposure to PM_2.5 on acute cough was observed, with a delayed effect for seven days. The odds ratio （OR） was 1.21（95% CI：1.06,1.37） for each increment of 10 µg/m³ in PM_2.5 on lag day1, and the effect of PM_2.5 sliding average was the highest （OR=1.19; 95% CI：1.05,1.37）from lag day 0 to lag day 4. The stratified analyses revealed that a higher risk of onset was observed in females （OR=1.25, 95%CI： 1.04, 1.50） than that in males （OR=1.10, 95%CI： 0.92, 1.33）（P<0.05）. Conclusion PM_2.5 can increase the risk of acute cough in the short term, and women had higher risk of acute cough induced by PM_2.5 exposure.

Objective To understand current mental health status and explore changing trend and influencing factors of middle school students in Taishan City, so as to provide scientific basis of effective mental health education for middle school students. Methods Based on the “Mental Health Scale for Middle School Students” and “Health Risk Behavior Monitoring Questionnaire for Adolescents in Guangdong Province ”, multistage stratified cluster random sampling method was used to investigate the middle school students in Taishan City in 2016 and 2019 separately. Data were descriptively analyzed. Factors influencing health risk behaviors on mental health among middle school students in Taishan City were determined by multivariate logistic regression. Results A total of 1 901 middle school students in Taishan were surveyed in 2016 and 2019. In 2016, there were 979 students, including 556 boys and 423 girls. In 2019, there were 922 students, including 468 boys, and 454 girls. Their ages were 12-20 years, with an average age of 16 years. The incidence of mental health problems among the students in 2019 （39.15%） was higher than that in 2016 （31.87%）. The incidence of mental health problems of girls （40.48%） was higher than that of boys （31.05%）, that of senior high school students （45.30%） was higher than that of junior high school students （30.69%） and that of vocational middle school students （30.10%） （P<0.01 for all）. The average scores of mental health of girl students, high school students, and vocational middle school students in 2019 were higher than those in 2016 （P<0.05 or P<0.01）. Both in 2016 and 2019, students with behaviors of lack of exercise （OR=1.957, 2.333）, self injury （OR=2.144, 2.289）, suicidal ideation （OR=3.347, 3.270）, internet addiction （OR=4.185, 10.592）, unhealthy diet（OR=1.727）in 2016, gambling in 2019 （OR=2.034） had higher risk of mental health problems. Conclusion The incidence of mental health problems of middle school students in Taishan City showed an upward trend. Comprehensive interventions should be strengthened on health risk behaviors of the middle school students, to improve their mental health.

Objective To determine effects of konjac compound on lipid metabolism and oxidative stress in obese rats and explore its mechanism of lipid metabolism and oxidative stress. Methods SD rats were used to establish an obesity model. The rats were divided into a model group and konjac compound administration groups at different doses. After 6 weeks of intervention, the indexes of blood lipid, adipokine, and antioxidant were detected. Results After 6 weeks of the experiment, the differences in body mass and fat/body ratio between the groups were statistically significant （P<0.05 or P<0.01）. The body weight and fat/body ratio of the konjac compound in the low, medium and high administration groups decreased with the increase of the dose concentration. Levels of serum triacylglycerol （TG）, total cholesterol （TC）, high-density lipoprotein cholesterol （HDL-C）, and blood glucose in the high-dose konjac compound group, and levels of serum TG and blood glucose in the middle-dose group decreased significantly （P<0.05 or P<0.01）. In the low-, medium-, and high-dose administration groups, HDL-C increased with the increase of konjac compound dosage. Statistically significant differences in leptin, adiponectin, superoxide dismutase （SOD）, malondialdehyde （MDA）, glutathione peroxidase （GSH-PX） were observed among the groups （P<0.05 or P<0.01）. With the increase of the konjac compound dose in the low-, medium-, and high-dose groups, the serum leptin and MDA levels decreased, but the levels of adiponectin, SOD, and GSH-PX increased. Conclusion The konjac compound can effectively improve the blood lipid disorder, reduce fat and weight, inhibit the oxidative stress reaction in the process of obesity, and prevent and treat obesity of obese rats.

Objective To explore the current situation and influencing factors of female perimenopausal syndrome （PPS） in Hainan Province. Methods A simple random sampling method was used to select women aged 40 to 60 who participated in the physical examination in a medical examination center of a hospital in Hainan Province from 2017 to 2019 to conduct a questionnaire survey. Descriptive epidemiological analysis methods were used to analyze the incidence of PPS and influencing factors in this population. Results A total of 2 055 women aged 40 to 60 years old were included in the survey. The average age was （51.68 ± 4.14） years old, with 53.92% aged 40 to 49; 86.08% Han nationality; and 40.58% normal BMI. The incidence of PPS in this population was 21.22%.Multivariate logistic regression analysis showed that age ≤50 years （OR=0.292）, working （OR=0.476）, knowledge of PPS （OR=0.493）, regular calcium supplementation or consumption of dairy products （OR=0.243）, regular physical exercise People （OR=0.589） have a lower risk of PPS, the larger the BMI （OR=3.346）, the lower the education level （OR=1.863）, the age of menarche ≤13 years （OR=1.699）, the parity ≥3 times （OR= 2.711）. Those with lower per capita monthly income （OR=4.288） have higher risk of PPS. Conclusion The incidence of PPS in women aged 40 to 60 in Hainan Province is relatively high, and there are many factors that affect the incidence of PPS. It is recommended to take corresponding measures to prevent or alleviate the risk of PPS in this population according to different ages, employment, PPS awareness, and living habits.

Objective To analyze the cancer incidence and mortality in Zhuhai in 2016. Methods Based on data of cancer incidence and deaths in Zhuhai in 2016, the incidence and mortality rates, ranking and constituent ratio were calculated. The Joinpoint Program was used to analyze the trend of cancer incidence and mortality from 2010 to 2016. Results The crude cancer incidence rate was 286.41/10⁵ in Zhuhai in 2016, with Chinese age-standardize rate of 222.69/10⁵. The main cancers were female breast cancer, lung cancer, colorectal cancer, liver cancer, and cervical cancer. The top 10 malignant tumors accounted for 72.75% of all cancers. The crude mortality rate of cancer was 116.16/10⁵, with Chinese age-standardize rate of 88.83/10⁵. The most common causes of cancer deaths were ranked as lung cancer, liver cancer, colorectal cancer, female breast cancer, and stomach cancer. The top 10 cancer deaths accounted for 80.27% of all cancer deaths. During 2010-2016, the cancer incidence and mortality in Zhuhai showed a significant upward trend （incidence： APC=3.27%, P<0.05; mortality： APC=3.03%, P<0.01）. Conclusion The cancer incidence and mortality showed an increasing trend in Zhuhai. Female breast cancer, lung cancer, colorectal cancer, liver cancer and cervical cancer are the main cancers to be prevented and treated.

Objective To understand the death status of people living with HIV/AIDS and analyze the related influencing factors in Longgang District, Shenzhen. Methods HIV/AIDS patients with current residential address in Longgang District, Shenzhen City from January 1, 2010 to December 31, 2018 were selected through the China information system for HIV/AIDS comprehensive prevention and control. Cox proportional hazard model was used to analyze the factors influencing the death on HIV/AIDS cases. Results A total of 590 HIV/AIDS cases were chosen, including 236 deaths （187 males and 49 females）. Multi-factor Cox regression analysis showed that the risk of death in married, divorced or widowed persons was 0.003 time and 0.418 time that in unmarried persons; the mortality risk of AIDS patients at diagnosis was 9.149 times that of HIV-infected persons; the risk of death from heterosexual transmission, homosexual transmission, and blood collection and supply was 0.319, 0.079, and 0.004 times that of injecting drug use, respectively; the risk of death in those who were not tested for CD4 was 9.166 times that in those who were tested; the risk of death in patients receiving antiviral therapy was 0.052 time that in patients without antiviral therapy. Conclusion The mortality of HIV/AIDS cases in Longgang District, Shenzhen City was affected by many factors. Of them, CD4 testing and antiretroviral therapy could effectively reduce the risk of mortality among HIV/AIDS cases.

Objective To detect effects of matrix Gla protein （MGP） on bone mass and the underlying mechanism. Methods MGP expression was interfered with recombinant adeno-associated virus （rAAV） in mice. The bone mass was examined by microCT analysis. The formation of osteoclasts was determined by tartrate resistant acid phosphatase （TRAP） staining. The serum level of TRAP5b was assessed by ELISA. Results Compared with the control group, the bone volume fraction of mice treated with MGP interference was significantly reduced, the number and the thickness of the trabecular bone were also significantly reduced, and the interval of the trabecular bone was significantly increased （P<0.01 for all）. The number of TRAP-positive osteoclasts in mouse femoral slices increased, and the level of serum TRAP5b increased significantly （P<0.01）. Conclusion MGP may regulate bone mass by inhibiting osteoclast formation and bone resorption.

Objective To determine the prevalence and influencing factors of hypertension complicated with diabetes mellitus （DM） in elderly residents aged 60 years and over in Shenzhen. Methods From July 2017 to October 2018, cluster sampling method was used to select all registered permanent residents aged ≥60 years from all 51 community health service centers under the jurisdiction of Luohu District, Shenzhen. Questionnaire surveys, physical examinations, and laboratory tests were conducted to collect relevant information. Results A total of 7 982 residents were surveyed, with an average age of 67.68 ± 5.41 years, and more females （57.2%）. Of the all participants, 1 257 were found to have hypertension with DM, with a prevalence rate of 15.7%. Multivariate logistic regression showed that the elderly aged 70-79 years （OR=2.60）, 80-92 years （OR=3.91）, and with overweight （OR=1.82）, obesity （OR=4.16）, abnormal HDL-C （OR=2.12）, and hyperlipidemia （OR=1.59） were more likely to have hypertension complicated with DM; the elderly with higher levels of education and more frequent consumption of fresh fruit, rice and soybean products were less likely to have hypertension with DM; compared with the group with education levels at primary school or below, the OR values of the group with education levels at senior high school/technical secondary school, college/undergraduate and above were 0.82 and 0.65; compared with the group eating fresh fruits<4 times/month, the OR values of the group having fresh fruits 4-11 times/month and≥12times/month were 0.55 and 0.46, respectively; compared with the group eating rice<12 times/month, the OR value of the group eating rice≥12 times/month was 0.46; compared with the group eating soybean products<4 times/month, the OR value of the group eating soybean products≥12 times/month was 0.80. Conclusion The prevalence of hypertension complicated with DM in the elderly in Shenzhen is relatively high. The risk factors for hypertension with DM are old age, overweight, obesity, abnormal HDL-C and hyperlipidemia. Higher education levels and intake of more fresh fruits, rice and soybean products may be the protective factors.

Objective To analyze and evaluate the hospital bed occupancy in 21 cities in Guangdong Province. Methods Based on the four indicators of the hospital bed occupancy, average length of hospitalization stay, bed working day, and bed turnover times in 21 cities in Guangdong Province. The Weight Standard Forming Calculation, combined with TOPSIS method, was used to analyze and evaluate the bed utilization efficiency of hospitals. Results The hospital bed occupancy rate was 83.0%, average length of hospitalization stay was 7.7 days, the bed working days was 303.0 days, and the number of bed turnovers was 38.8 times in 2018. The top 5 cities with the highest bed utilization efficiency were： Meizhou, Qingyuan, Zhongshan, Chaozhou, and Yunfu, with S_i values ??of 0.791, 0.762, 0.737, 0.707, and 0.643, respectively. The 5 cities from the lowest bed used efficiency were： Shanwei, Dongguan, Zhaoqing, Maoming and Heyuan, with evaluation scores （S_i values） ??of 0.199, 0.338, 0.340, 0.401, and 0.415, respectively. Conclusion The average bed utilization rate was 83.0% in 21 cities in Guangdong Province. As an important medical resource, the hospital bed occupancy should be kept at about 85% to achieve the best utilization rate of medical resources and help maintain a good level of medical services.

Objective To analyze the status of neonatal nosocomial pulmonary infection （PI） in hospitalized newborns, and analyze the distribution and drug resistance of the pathogenic bacteria. Methods Data of all hospitalized neonates admitted to the pediatric department from 2010 to 2019 were collected through the medical record management information system of a hospital in Guang'an City from 2015 to 2019. Descriptive epidemiological analysis was used to analyze the occurrence of PI in the hospital, pathogenic bacteria and susceptibility to commonly used antibiotics. Results A total of 5 673 neonates hospitalized in the neonatal department of a hospital in Guang'an from 2015 to 2019 were included. The male to female sex ratio was 1.11：1. Of the all neonates, 64.93% had gestational age of 34 to 41 weeks, 77.31% had birth weight of 2.5 to 3.8 kg, 60.16% stayed in the hospital more than 7 days, 54.83% were natural childbirth, and 88.38% had Apgar scores of 8-10. Nosocomial PI infection occurred in 185 newborns, with an infection rate of 3.28%; 232 strains of pathogenic bacteria were isolated and cultured, including 164 Gram negative strains （70.69%）. Multivariate logistic regression showed that birth weight <2.5 kg （OR=3.593）, gestational age <34 weeks （OR=2.653）, hospital stay>7 days （OR=1.941）, Apgar score<7 points （OR=2.440 ）, invasive operation （OR=3.323）, and cesarean section （OR=2.492） were the risk factors for nosocomial PI in neonates hospitalized in neonatal department. Conclusion There were neonatal nosocomial PIs in Guang'an City. The risk of infection was related to many factors. Gram-negative bacteria were the main pathogens. The hospital should take targeted prevention and treatment strategies to reduce and prevent the risk of neonatal nosocomial PI.

Objective To understand the anxiety and its influencing factors among college students during the COVID-19 epidemic, so as to provide references for psychological counseling of college students. Methods Using convenient sampling method, an online survey was conducted among college students from February 16 to 20, 2020. The suevey contents mainly included basic knowledge about COVID-19, personal protective behavior, related attitudes to COVID-19, and the Generalized Anxiety Disorder 7-item （GAD-7） scale. Results A total of 1 100 college students were investigated, with an average age of 22.5 ± 2.5 years, mainly from South China （37.8%）. The detection rate of anxiety was 38.4%, in which the detection rate of mild, moderate and severe anxiety was 22.5%, 10.5%, and 5.4%, respectively. The multivariate analysis showed that the risk factors for the college students to have anxiety were the fear of discrimination when returning to school from the epidemic areas （OR=2.535）, the fear of falling behind in academic progress （OR=2.304）, and the fear of sharing the dormitory with students from the epidemic areas after returning to school （OR=1.531）. The students who were dissatisfied with the emergency management of the school （OR=1.793） and in the graduating class （OR=1.452） were more likely to have anxiety. Compared with medical students, liberal arts students were more likely to have anxiety （OR=1.876）. Conclusion During the epidemic of COVID-19, college students had a certain degree of anxiety. Colleges and universities should pay attention to students' mental health during the epidemic period, strengthen the emergency management, do a good job in psychological counseling of students, prevent regional discrimination on campus, scientifically and rationally arrange students' return to school and resumption of classes, so as to maximize the maintenance of students' physical and mental health.

Objective To understand the status of knowledge, attitude and practice of COVID-19 among adult residents in Panyu District, Guangzhou, and verify the effect of health education. Methods Adult residents in Panyu District, Guangzhou City were invited to participate in a questionnaire online survey from February 23 to March 13, 2020. According to the project weight or grade, SPSS 19.0 software was used for statistical analysis. Results A total of 35 797 adult residents were investigated. The high cognition rate for respondents was 83.9%.The top three awareness rates were transmission route（99.3%）, washing hands after going home（99.2%）, and symptoms after infection（98.9%）. The holding rate of positive attitude to COVID-19 was 87.0%. Of the respondents, 99.9% agreed to wash their hands frequently and 99.9% believed that the country can overcome the epidemic. The good behavior rate was 86.6%. The top two health behavior formation rates were reducing going out （98.3%） and washing hands frequently （98.0%）. Multivariate logistic analysis showed that the respondents, who were female, had high education level, professional medical staff, Guangzhou household registration, living permanently in city, high cognitive level, and positive attitude, had higher health behavior implementation level. Conclusion Health education of COVID-19 was effective. Residents had high awareness of COVID-19 and took active protective measures. Key health education should be carried out for the vulnerable groups who were male, with low education level, lower knowledge, attitude and practice level of COVID-19, negative attitude, and poor implementation of health behavior.

Objective To analyze characteristics of coronavirus disease 2019 （COVID-19） epidemic in Guangzhou, so as to provide scientific evidence for prevention and control practice. Methods Epidemiological investigation was carried out on the confirmed COVID-19 patients and asymptomatic cases in Guangzhou. The epidemiological and clinical characteristics of the cases were described by descriptive epidemiological method, and factors related to the source of infection and disease severity were determined. Results As of March 11, 2020, a total of 361 COVID-19 cases were reported in Guangzhou, including 347 confirmed cases （96.1%） and 14 cases of asymptomatic infection. The cases were mainly imported from areas outside Guangzhou （73.2%） and 80.3% of them were imported from Hubei Province （204/254）. Of the confirmed cases, 63.7% were associated with cluster outbreaks, of which 85.1% were household clusters; 93.9% developed mild symptoms or common pneumonia. The most common symptom was fever （78.1%）, followed by dry cough （45.9%）. Only one death was reported. Factors including male, elder age-group, retirees, self-reported having a history of cardiovascular disease or having a history of admission to medical institutions 14 days prior to disease onset were associated with serious cases（P<0.05 or P<0.01）. Conclusion The COVID-19 cases in Guangzhou were mainly imported from Hubei Province, local infections occurred in some areas, and many were household clusters, but no community transmission was observed.