AIM:To explore the effects of miR-21 on biological behavior of colon cancer cells and their sensi-tivity to epidermal growth factor receptor monoclonal antibody cetuximab .METHODS:Lentiviral vectors were constructed to generate up-and down-regulations of miR-21 lentiviruses (LV-miR-21 and LV-anti-miR-21, respectively), and the cor-responding negative control viruses (LV-miR-21 NC and LV-anti-miR-21 NC, respectively) were also constructed.The vi-ruses were used to infect human colon cancer RKO cells .The changes of the miR-21 expression level , the cell prolifera-tion, the colony-forming ability, the cell apoptosis and the sensitivity of the cells to cetuximab were detected by real -time PCR, MTT assay, soft agar colony assay , flow cytometry and CCK-8 assay.RESULTS: The lentivirus titers of LV-miR-21, LV-miR-2 NC, LV-anti-miR-21 and LV-anti-miR-21 NC were 3.0 ×1012 TU/L, 6.0 ×1011 TU/L, 2.0 ×1012 TU/L and 8.0 ×1011 TU/L, respectively.The infection efficiency was over 80% by the observation of green fluorescence .The miR-21 expression level , the cell proliferation , and the colony-forming ability in LV-miR-21 group were significantly higher than those in LV-anti-miR-21 group.The early apoptotic rate and the inhibitory rate of cetuximab for the cells in LV-anti-miR-21 group were higher than those in LV-miR-21 group.CONCLUSION: miR-21 promotes the proliferation of colon cancer cells.Down-regulation of miR-21 enhances the sensitivity of the colon cancer cells to the targeted therapy drug cetuximab.

Objective: To investigate the distribution and drug resistance situation of staphylococcus aureus (SA) and methicillin-resistant staphylococcus aureus (MRSA) from the classroom environments in primary schools of Guangzhou. Methods: The air and the surfaces of door handles, desks, chairs, light switches and floor were sampled in the classrooms of 8 primary schools selected through stratified clustering method in Guangzhou from May to June, 2016. SA and MRSA were isolated and identified, and drug sensitivity tests were conducted. Results: A total of 760 samples were collected, the detection rate of SA and MRSA were 8.8% and 4.2%, respectively. There were statistically significant differences in the detection rate of staphylococcus aureus among different sampling sites(P<0.01).Detection of SA and MRSA on the floor,light’s witches and surface of deskes was both above 6.0%. The multiple drug resistance rate of MRSA was up to 100.0%, and the main resistance mode was Penicillin-Erythromycin-Rifampin-Tetracycline-Teicolanin. Conclusion MRSA can be detected in air, door handles, desk surface, chair surface, light switch and floor of primary schools. Relevant administration departments should pay attention to the environments health of Guangzhou primary schools.

Objective: To explore the association between maternal pre pregnancy and pre delivery overweight with overweight and obesity among offspring during adolescence in Guangzhou, and to provide evidence for child obesity prevention. Methods: Based on the routine physical examination of primary and secondary school students in Guangzhou, random sampling was used to 6 middle schools and questionnaire survey was conducted among 3 384 students and their parents. Students with overweight and obesity were included in the case group, and the other students were included in the control group. Propensity Score Matching (PSM) was adopted to reduce selection bias. Logistic regression model and χ 2 test were used to analyze the data before and after PSM. Results: The result of univariate analysis showed that there were statistically significant differences between overweight/obese group and the control group by gender, schooling stage (middle and high schools), picky eater, family history of obesity, family monthly income, delivery mode, high birthweight, and gestational weight gain before PSM( χ 2=42.38, 10.64, 14.47, 26.85, 10.58, 13.59 , 15.53, 20.64, P <0.05). After PSM, results showed that there were no statistically significant differences between overweight/obese group and the control group in middle and high schools, and mother delivery mode( P >0.05). Logistic regression analysis showed that the risk of overweight and obesity of maternal pre pregnancy on adolescent offspring was 1.54 times higher than control group (95% CI =1.01-2.36) before PSM, and the overweight and obesity of maternal predelivery also increased the risk of overweight and obesity of adolescent offspring( OR=2.35, 95%CI =1.67-3.31). After PSM, maternal overweight and obesity pre pregnancy ( OR=2.17, 95%CI =1.41-3.34) and maternal overweight and obesity pre delivery( OR=2.99, 95%CI =2.08-4.31) significantly increased the risk of overweight and obesity in adolescent offspring. Conclusion Maternal overweight and obesity pre pregnancy and pre delivery are associated with increased risk of overweight and obesity in adolescent offspring.

Objective: To investigate the antibiotic resistance spectrum and genetic characteristics of multidrug-resistant Staphylococcus aureus(MDRSA) nasal isolate among primary school students, and to provide a scientific basis for the prevention and control of masal MDRSA resistance and the selection of clincal drugs in children. Methods: Antibiotic susceptibility experiments were performed on all SA isolates of 1 705 primary school students from 8 primary schools in Guangzhou selected by using multistage cluster stratified sampling method. MDRSA antibiotic susceptibility spectrum was analyzed, and the resistant, virulence and immune evasion cluster(IEC) genes detected by polymerase chain reaction(PCR). Results: The prevalence of MDRSA nasal carriage was 20.76%(354/1 705), and the proportion of multidrug resistance among SA isolates was 96.20%(354/368). The predominant resistant antibiotics of MDRSA isolates were penicillin(99.72%), erythromycin(96.33%), clindamycin(90.96%) and teicoplanin(90.11%). Notably, 240(67.80%, 240/354) MDRSA isolates were resistant to more than six antimicrobial categories. And the predominant detection rates of resistant genes were BlaZ(92.66%), Tet(M)(49.72%), virulence genes Tst(25.42%) and IEC genes Sak(92.09%), Hlb(61.58%). Conclusion We found high prevalence of nasal colonization MDRSA from healthy children. Moreover, MDRSA isolates has a high resistant rate to multiple antibiotics, and the proportion of resistant to ≥6 antimicrobial categories is high.

Objective: To explore the effect of the comprehensive intervention on overweight and obesity among middle school students at the population level (health education lecture and official account push) and individual level (personalized dietary guidance), so as to provide a reference for preventing and controlling their overweight and obesity. Methods: Three junior high schools and three senior high schools were randomly selected in Guangzhou in 2018 by convenience sampling. Through physical examination, 1 457 overweight and obese students aged from 12 to 18 years old were screened. Intervention was administered through "Student Personalized Dietary Guidance" manual, health tweets on the official accounts, and health education lectures from September 2018 to December 2019. The Chi square test was used to compare the difference in overweight and obesity constituent ratio between the two groups before and after the intervention. And intervention effect was evaluated by analyzing the number needed to treated(NTT). Results: The proportion of overweight before the intervention was 66.71% (972/1 457), and decreased to 59.92% (873/1 457) after the intervention; the proportion of obesity before the intervention was 33.29% (485/1 457), which decreased to 26.63% (388/1 457) after the intervention. Among obese students, the smallest NNT was seen in the girl group aged 12-13 years (NNT=2.6, 95% CI =1.9-4.1), while the largest NNT in the boy group aged 14-18 years (NNT=5.9, 95% CI =4.7-8.1). The NNT of the girls aged 12-13 years was the smallest (NNT=2.7, 95% CI =2.2-3.5), and the NNT of the boys aged 14-18 years was the largest (NNT=7.4, 95% CI =6.0-9.7). Conclusion Health education at population level (health education lectures, official account push) with individual level (personalized dietary guidance) can effectively intervene overweight and obesity among middle school students in Guangzhou.

This article reviews the clinical studies about the treatment of allergic rhinitis （AR） with traditional Chinese medicine （TCM） in recent years. AR is a common and frequently occurring disease in the department of otolaryngology. The common manifestations of AR include nasal congestion， sneezing， runny nose， and nasal itching. AR， belonging to the category of rhinitis， is a dominant disease in the TCM treatment of otorhinolaryngologic diseases and head and neck diseases. The ancient literature has laid a solid theoretical basis on the etiology and pathogenesis of AR. According to the ancient literature， the theoretical basis， and their own experience， modern doctors classified the causes of AR into the disorders in Zang-fu organs and six meridians. Most of the explanations focus on the disorders in Zang-fu organs， especially the lung， spleen， and kidney. The clinical studies in this field mainly involve TCM treatment alone， integrated TCM and Western medicine treatment， and TCM external treatment. These therapies have good efficacy in the clinical treatment of AR. Among them， TCM treatment alone has significant advantages in alleviating the symptoms and nasal signs， declining the scores of related scales， and reducing the eosinophil count （EOS） of nasal secretions， with definite long-term efficacy. Integrated TCM and Western medicine treatment can complement with each other. The TCM external treatment methods include acupuncture， moxibustion， acupoint catgut embedding， acupoint application， and nasal irrigation with TCM， which are safe， simple， acceptable by patients and have good therapeutic effect. Finally， the clinical research status of TCM treatment of AR was summarized， and suggestions were put forward from three aspects： standardizing the clinical research protocol of TCM， encouraging pure TCM research， and exploring the mechanism of TCM treatment on the basis of frontier research achievements. This review aims to provide higher-level evidence for subsequent clinical research and promote the research on dominant AR diseases.

BACKGROUND: Numerous studies have concentrated on high-dose radiation exposed accidentally or through therapy, and few involve low-dose occupational exposure, to investigate the correlation between low-dose ionizing radiation and changing hematological parameters among medical workers. METHODS: Using a prospective cohort study design, we collected health examination reports and personal dose monitoring data from medical workers and used Poisson regression and restricted cubic spline models to assess the correlation between changing hematological parameters and cumulative radiation dose and determine the dose-response relationship. RESULTS: We observed that changing platelet of 1265 medical workers followed up was statistically different among the cumulative dose groups (P = 0.010). Although the linear trend tested was not statistically significant (P CONCLUSION We concluded that although the exposure dose was below the limit, medical workers exposed to low-dose ionizing radiation for a short period of time might have increased first and then decreased platelets, and there was a dose-response relationship between the cumulative radiation dose and platelets changing.
Adult ; Aged ; Blood Platelets/radiation effects* ; Female ; Health Personnel/statistics & numerical data* ; Humans ; Male ; Middle Aged ; Occupational Exposure/adverse effects* ; Prospective Studies ; Radiation Dosage ; Radiation Exposure/adverse effects* ; Radiation, Ionizing ; Young Adult