Objective: To understand the trend of changes of hygiene status in the teaching environment among primary and secondary schools in Beijing City during 2016-2020, so as to provide basis for further improving the teaching environment and campus hygiene conditions in primary and secondary schools. Methods: A proportional systematic sampling method covered over 50% of schools selected annually in Beijing from 2016 to 2019, and 34% were selected in 2020. Two representative classrooms were selected from each selected school for testing based on their structure and other factors, with 6 196 classrooms supervised, from 2016 to 2020,1 330,1 312,1 384,1 322,848 classrooms were monitored for each year. Results: From 2016 to 2020, the overall lighting qualification rate of classrooms (lighting coefficient 72.8%, window to floor area ratio 41.8%, rear wall reflectance ratio 42.2%, blackboard reflection ratio 37.4%), the overall qualification rate of average blackboard illumination and uniformity (50.6%, 34.9 %), and the overall qualification rate of desk and chair allocation (58.6%) were all below 80%. The overall qualification rate of per capita classroom area (87.5%), blackboard size (83.2%), average desk illumination ( 80.1% ), average desk illumination and uniformity (82.9%), the distance between lamp and desk (99.1%), carbon dioxide ( 86.6% ), temperature (84.9%), and noise (96.6%) were all above 80%. The following indicators, blackboard size, the distance between lamp and desk, average blackboard illumination, lighting coefficient, blackboard reflectance, rear wall reflectance, carbon dioxide, temperature, and noise ( χ 2=78.38, 9.71, 11.76, 320.59, 37.63, 58.45, 236.45, 1 347.56, 101.97), had statistically significance between years. Among those indicators, the qualified rates of blackboard size, blackboard reflectance, lighting coefficient, and noise had been increasing year by year ( χ 2 trend =69.98, 15.82, 240.02, 5.77) ( P <0.05). The qualified rates of per capita classroom area, window to floor area ratio, and blackboard reflection ratio in primary schools (81.6%, 39.8%, 36.3%) were all lower than those in secondary schools (94.9%, 44.5%, 40.3%) ( χ 2=246.32, 12.03, 10.51, P <0.05). The qualified rates of blackboard size, average blackboard illumination, average blackboard illumination and uniformity, and desk and chair allocation (89.3%, 55.6% , 36.0%, and 60.2%) were all higher than those in secondary schools (75.4%, 44.1%, 33.3%, and 56.5%) ( χ 2=209.33, 78.41, 4.44, 8.22) ( P <0.05). The qualified rates of average desk illumination and uniformity, average blackboard illumination, rear wall reflectance ratio, desk and chair allocation, carbon dioxide, temperature, and noise indicators in urban area (82.9%, 84.1% , 51.9%, 45.0%, 60.9%, 91.2%, 89.5%, 97.8%) were all higher than those in suburban area (77.3%, 81.7%, 49.2%, 39.5%, 56.3%, 82.3%, 80.4%, 95.5%) ( χ 2=31.16, 6.28, 4.36, 16.40, 13.39, 105.29, 98.23, 24.66， P <0.05). The qualified rates of the distance between lamp and desk, lighting coefficient, window to floor area ratio, blackboard size, blackboard reflection ratio, average blackboard illumination and uniformity, and per capita classroom area in urban areas (98.8%, 65.2%, 34.3%, 76.7%, 35.9%, 30.1%, 84.6%) were all lower than those in suburban areas (99.4%, 81.4%, 49.8%, 89.7%, 40.2%, 39.6%, 90.3%) ( χ 2=6.80, 171.67, 132.43, 188.46 , 12.45, 60.28, 44.82) ( P <0.05). Conclusions The main problems in the teaching environment of schools in Beijing are classroom lighting, as well as desk and chair allocation. The findings suggest technical rationality and operability of relevant standard should be considered when under revision, and standard training and supervision management should be strengthened, with the aim of teaching environment improvement.

Objective To explore the role and mechanism of exosomes derived from bone marrow mesenchymal stem cells(BMSCs)overexpressing transglutaminase 2(TGM2)in lactate-mediated oxidative stress-induced apoptosis in nucleus pulposus cells.Methods Twenty 6-week-old male SD rats(350±50 g)were used to extract nucleus pulposus cells.Lactic acid was utilized to establish a model of oxidative stress-induced apoptosis in primary nucleus pulposus cells.Lentiviral vectors carrying TGM2 were employed to transfect BMSCs to overexpress the protein,and then exosomes were extracted from the BMSCs and identified.Subsequently,to investigate the potential mechanisms of TGM2-overexpressing exosomes against oxidative stress-induced apoptosis in nucleus pulposus cells,flow cytometry was used to detect the production of reactive oxygen species(ROS),and Western blotting and immunofluorescence assay were applied to measure the expression levels of Bax,Bcl-2,Cleaved-Caspase3,p-PI3K,p-Akt,n-Nrf2,c-Nrf2 and HO-1,and Nrf2 nuclear translocation.The rate of oxidative stress-induced apoptosis in nucleus pulposus cells and changes in the PI3K/Akt/Nrf2 pathway were assessed in 4 groups of cells(n=3):control group,lactate treatment group,lactate+control exosome group,and lactate+TGM2-overexpressing exosomes group.Results Lactic acid of 10 mmol/L was found to be more effective in inducing oxidative stress-induced apoptosis in nucleus pulposus cells(P＜0.05).Both control BMSCs and TGM2-overexpressing BMSCs could produce exosomes and stably overexpress TGM2(P＜0.05,P＜0.01).Compared with the lactate treatment group,the nucleus pulposus cells in the lactate+TGM2-overexpressing exosome group and the lactate+control exosome group showed reduced apoptotic rates(P＜0.05),as well as decreased ROS level(P＜0.05).The lactate+TGM2-overexpressing exosome group exhibited better anti-apoptosis and ROS accumulation effects(P＜0.05).Additionally,the expression of Bax and Cleaved-Caspase3 was decreased(P＜0.05),that of Bcl-2 protein was increased(P＜0.05),the phosphorylation of PI3K/Akt was enhanced(P＜0.05),and both Nrf2 nuclear translocation and the expression of the antioxidant stress factor HO-1 were increased in nucleus pulposus cells.The lactic acid+TGM2-overexpressing exosome group showed stronger anti-apoptotic effects and activation of the PI3K/Akt/Nrf2 pathway(P＜0.05).Conclusion Exosomes derived from BMSCs overexpressing TGM2 can inhibit lactate-mediated oxidative stress-induced apoptosis in nucleus pulposus cells,and the mechanism may be related to the activation of the PI3K/Akt/Nrf2 pathway.

BACKGROUND: Screening using low-dose computed tomography (LDCT) is a more effective approach and has the potential to detect lung cancer more accurately. We aimed to conduct a meta-analysis to estimate the accuracy of population-based screening studies primarily assessing baseline LDCT screening for lung cancer. METHODS: MEDLINE, Excerpta Medica Database, and Web of Science were searched for articles published up to April 10, 2022. According to the inclusion and exclusion criteria, the data of true positives, false-positives, false negatives, and true negatives in the screening test were extracted. Quality Assessment of Diagnostic Accuracy Studies-2 was used to evaluate the quality of the literature. A bivariate random effects model was used to estimate pooled sensitivity and specificity. The area under the curve (AUC) was calculated by using hierarchical summary receiver-operating characteristics analysis. Heterogeneity between studies was measured using the Higgins I2 statistic, and publication bias was evaluated using a Deeks' funnel plot and linear regression test. RESULTS: A total of 49 studies with 157,762 individuals were identified for the final qualitative synthesis; most of them were from Europe and America (38 studies), ten were from Asia, and one was from Oceania. The recruitment period was 1992 to 2018, and most of the subjects were 40 to 75 years old. The analysis showed that the AUC of lung cancer screening by LDCT was 0.98 (95% CI: 0.96-0.99), and the overall sensitivity and specificity were 0.97 (95% CI: 0.94-0.98) and 0.87 (95% CI: 0.82-0.91), respectively. The funnel plot and test results showed that there was no significant publication bias among the included studies. CONCLUSIONS Baseline LDCT has high sensitivity and specificity as a screening technique for lung cancer. However, long-term follow-up of the whole study population (including those with a negative baseline screening result) should be performed to enhance the accuracy of LDCT screening.
Humans ; Adult ; Middle Aged ; Aged ; Lung Neoplasms/diagnostic imaging* ; Early Detection of Cancer ; Sensitivity and Specificity ; Mass Screening ; Tomography, X-Ray Computed

Objective To determine the causal relationship between acromegaly and colon cancer by using two-sample Mendelian randomization. Methods Genetic loci closely related to acromegaly in the whole genome-wide association study (GWAS) were selected as tool variables, and the genetic data of colon cancer from different GWASs were analyzed by two-sample Mendelian randomization (MR).The inverse variance weighting method (IVW) of the random effect model was used for analysis, and MR-weighted median and MR-Egger methods were used to supplement the analysis. Results were presented as OR values. Results Four SNPs closely related to acromegaly were obtained as tool variables, and the multiplicity test of tool variables showed that P=0.59.Three methods were used to estimate causal effects.The IVW analysis were OR=1.00(0.99-1.001) and P=0.42;the MR-Egger analysis results were OR=1.00(0.99-1.001) and P=0.42;and the Weighted median analysis results were OR=1.00(1.00-1.001) and P=0.03.The sensitivity test showed that the confidence interval of the tool variable SNP passed through 0, indicating the robustness of the MR results. Conclusion Acromegaly is not an independent risk factor for colon cancer.

OBJECTIVE To evaluate the clinical efficacy and safety of original and generic entecavir(ETV) in the treatment of chronic hepatitis B. METHODS Domestic and foreign literatures were systematically reviewed to evaluate the efficiency and safety. Qualitative combined with quantitative methods were used to evaluate and analyze. RESULTS Meta-analysis results showed that there were no significant differences in HBV-DNA negative conversion rate, ALT normalization rate, serum HBeAg negative conversion rate, HBeAg serum conversion rate, HBeAg/HBeAb serum conversion rate and incidence of adverse reactions between generic and original ETVs after 12 and 48 weeks of medication. Subgroup analysis of different treatment courses showed no statistical significance in each index. CONCLUSION The results of this study shows no significant differences between the two drugs in terms of clinical efficacy and safety considerations. However, limited by the quality and quantity of included literature, a large sample and multicenter RCT is still needed to confirm the conclusion.

Drug optimization, which improves drug potency/specificity by structure‒activity relationship (SAR) and drug-like properties, is rigorously performed to select drug candidates for clinical trials. However, the current drug optimization may overlook the structure‒tissue exposure/selectivity-relationship (STR) in disease-targeted tissues vs. normal tissues, which may mislead the drug candidate selection and impact the balance of clinical efficacy/toxicity. In this study, we investigated the STR in correlation with observed clinical efficacy/toxicity using seven selective estrogen receptor modulators (SERMs) that have similar structures, same molecular target, and similar/different pharmacokinetics. The results showed that drug's plasma exposure was not correlated with drug's exposures in the target tissues (tumor, fat pad, bone, uterus), while tissue exposure/selectivity of SERMs was correlated with clinical efficacy/safety. Slight structure modifications of four SERMs did not change drug's plasma exposure but altered drug's tissue exposure/selectivity. Seven SERMs with high protein binding showed higher accumulation in tumors compared to surrounding normal tissues, which is likely due to tumor EPR effect of protein-bound drugs. These suggest that STR alters drug's tissue exposure/selectivity in disease-targeted tissues vs. normal tissues impacting clinical efficacy/toxicity. Drug optimization needs to balance the SAR and STR in selecting drug candidate for clinical trial to improve success of clinical drug development.

Objective:To explore the clinical effect and application value of simultaneous modulated accelerated radiotherapy (SMART) in the suspicious positive lymph nodes of head and neck.Methods:From January 2017 to February 2019, 60 patients with suspected positive lymph nodes in the head and neck in the Hanzhong Central Hospital of Shaanxi Province were divided into experimental group and control group according to different treatment plans, and 30 patients in each group were included. In the experimental group, 63.36 to 66.66 Gy patients were treated with SMART, while in the control group, 54.12 to 60.06 Gy patients were treated with conventional neck prophylactic radiation. In order to evaluate the feasibility of the method, the change of the short diameter of the largest cross section of the suspicious positive lymph nodes in the two groups were observed, and the adverse reactions in the treatment of the two groups were analyzed.Results:There was no significant difference between the two groups before treatment ( P>0.05). After treatment, the size of short diameter of lymph nodes in the two groups was smaller than that before treatment. The maximum short diameter of the largest cross section of lymph nodes in the experimental group was smaller than that before treatment: (0.43 ± 0.07) cm vs. (0.72 ± 0.10) cm, and the difference was statistically significant ( P<0.05). In the control group, the maximum short diameter of the largest cross section of lymph node decreased after treatment, and the difference was not statistically significant ( P>0.05). After treatment, the reduction of the short diameter in the experimental group was more obvious than that in the control group. The maximum short diameter of the largest cross section between the two groups: (0.43±0.07) cm vs. (0.66±0.08)cm was statistically significant ( t = 11.523, P<0.05). Before treatment, hemoglobin (HGB) levels of the two groups were in the normal physiological range, and there was no significant difference between the two groups ( P>0.05); the white blood cell (WBC) levels of the two groups at different time after treatment were compared: in the first week (7.83 ± 2.53) × 10 9/L vs. (8.26 ± 3.16) × 10 9/L, in the third week (7.14 ± 3.65) × 10 9/L vs. (7.08 ± 2.53) × 10 9/L, in the fifth week (5.47 ± 2.81) × 10 9/L vs. (6.41 ± 2.57) × 10 9/L, and in the seventh week (4.36 ± 2.59) × 10 9/L vs. (4.98 ± 1.64) × 10 9/L, and there were statistical differences ( P<0.05), which indicated that the WBC index levels of the two groups were gradually decreased during the treatment, and the decreased degree of the experimental group was higher than that of the control group. The levels of HGB and PLT were maintained in the normal physiological range before and after treatment, and there was no significant difference between the two groups ( P>0.05). The main complications in the treatment of the experimental group were xerostomia and stomatitis. The adverse reactions in the control group were pain in the target area of radiotherapy. There was no significant difference between the two groups ( P>0.05). Conclusions:The application of IMRT is an effective method for the treatment of occult lymph node metastasis, and it is also a therapeutic diagnostic method, which can provide evidence for the study of the law of lymph node metastasis in the head and neck. The safety and tissue tolerance of IMRT in the treatment of suspicious positive lymph nodes in the head and neck are good, which can be used for the suspicious lymph nodes in the head and neck. The treatment of positive lymph nodes and the evaluation of patients′ prognosis provide an effective way of clinical treatment.

Disulfiram, a drug that has been used for alcohol dependence. As an approved drug in clinical medicine, disulfiram can be used as the anticancer drug in the treatment of breast cancer, prostate cancer, glioblastoma, lung cancer, etc. This paper summarized the mechanism of disulfiram for anticancer treatment and the function for liver cancer therapy, and we also analyzed the potential mechanism of disulfiram for the treatment of liver cancer and its’ value in the clinical application.

Objective: To evaluated the application of General Provisions of Safety and Health for Writing Boards(GB 28231-2011), and to provide basis for the revision and improvement of the standard. Methods: From June to October 2018, a questionnaire survey was conducted among 852 people engaged in the evaluation, use and production of writing boards in 8 districts of Beijing, Liaoning and Jiangsu. The contents of the survey include the awareness, implementation of the standard and evaluating the use of various parameters in the standard by personnel from different institutions. Results: The overall awareness ratio of the standard among staffs from health, education and enter prise was 78.26%. For the nominal size of the writing board and the vertical distance between the lower edge and the platform, the reasonableness considered lower by health professionals(62.50%, 37.50%) than that of education professionals(90.00%, 90.00%) and enterprise staffs(90.00%, 90.00%)(P<0.05); For the frequency and reasonableness of the nine parameters such as gloss and adhesion, the perception of each institution were significantly different(P<0.05), with proportion of professionals in health lower than experts in education and enterprise. For the two parameters of color and light resistance, each institution considered the maneuverability was not strong(P>0.05). Conclusion Propagation and implement is still needed to strengthen comprehension, because different institutions have different understandings towards the standard. There are still some problems waiting to be solved, such as different standard limits, poor enforceability of two parameters which are writing board color and light resistance.

BACKGROUND: It has been pointed out that perioperative hypothermia can increase the incidence of coagulation, acidosis, stroke, sepsis, pneumonia and myocardial infarction, so it is of great significance to monitor and maintain normal body temperature during perioperative period. OBJECTIVE: To design a medical carbon fiber thermostatic heating pad to prevent perioperative hypothermia and reduce complications. METHODS: The carbon fiber heating technology and medical equipment standard are combined and integrated into many advanced technologies. The system mainly consisted of power supply conversion, operation system, computer control system, PWM control and output, various heating pads and temperature controlling measurement system. A total of 200 patients undergoing epidural anesthesia in Zhengzhou First People's Hospital were randomly divided into two groups: the observation group (n=100) was treated with the medical carbon fiber thermostatic heating pad (adjusting temperature 38-40 oC), and the control group (n=100) with common quilt. The body temperature and shivering were monitored before operation, 10, 30 and 60 minutes after anesthesia, and 2 hours after operation. RESULTS AND CONCLUSION: (1) The heating pad had the characteristics of explosion proof, power purification, shielding isolation, output protection, computer control, and PWM modulation. (2) In clinical application, there was no skin irritation and skin allergy reaction in the observation group. (3) During operation, the body temperature of the observation group was relatively stable, and there was no significant difference in the body temperature in the observation group before and at 2 hours after operation (P> 0.05). However, the fluctuation of body temperature in control group was visible and showed a downward trend, and the body temperature in the control group showed a significant difference before and 2 hours after operation (P < 0.05). The body temperature of 10, 30, 60 minutes after anesthesia and 2 hours after operation was significantly higher in the observation group than the control group (P < 0.05). (4) The postoperative incidence of shivering in the control group was significantly higher than that in the observation group (18％ vs. 5％, P < 0.05). To conclude, the medical carbon fiber thermostatic heating pad is advanced in technology, safe and reliable in use, providing a new way for the prevention of perioperative shivering.