Objective: To investigate the level of arsenic exposure in rural drinking water and to assess the health risk caused by exposure to arsenic in Tongzhou District, Beijing Municipality in 2019, so as to provide insights into improving the quality of rural drinking water. Methods: Water samples were collected from self-provided wells in 196 villages of 7 townships in Tongzhou District from April to June, 2019, and the arsenic levels were measured in drinking water according to Standard examination methods for drinking water-Metal parameters (GB/T 5750.6-2006). The carcinogenic and non-carcinogenic risks of arsenic were evaluated in drinking water using the environmental risk assessment model recommended by the United States Environmental Protection Agency (EPA). Results: Totally 520 water samples were collected, and the median arsenic concentration was 0.001 2-0.050 0 mg/L. There were 67 water samples with arsenic levels exceeding the defined standard level (12.88%), and the proportions of arsenic levels exceeding the defined standard level were 57.69%, 17.24%, 12.20%, 6.52% and 1.31% in Songzhuang, Huoxian, Lucheng, Zhangjiawan and Yongdedian townships, and the arsenic levels did not exceed the defined standard level in Majuqiao or Taihu townships. The carcinogenic risk of arsenic was 3.135 7×10-4/a in drinking water, which exceeded the maximum acceptable risk, and the carcinogenic risk of arsenic all exceeded the maximum acceptable risk, with the highest value seen in Songzhuang Township (9.648 2×10-4/a). A high carcinogenic risk of arsenic was seen in men at ages of 60 to 80 years (3.012 8×10-4/a) and in women at ages of 80 years and older (2.949 0×10-4/a). The non-carcinogenic risk of arsenic was 0.696 8 in drinking water, indicating a low risk, and were 1.009 5 and 2.144 1 in Huoxian and Songzhuang townships, indicating a high risk. In addition, a high non-carcinogenic risk of arsenic was seen in men at ages of 60 to 80 years (0.669 5) and in women at ages of 80 years and older (0.655 3). Conclusion There was a high proportion of arsenic levels exceeding the defined standard level in rural drinking water in Tongzhou District, 2019, and there was a health risk, notably with the highest carcinogenic risk seen in residents at ages of 60 years and older. Effective interventions are needed to reduce arsenic levels in drinking water.

Objective To investigate the clinical effects of subeutanous fistula excision for the long-path low anus fistula.Methods Operation for long-path low anus fistula,fistula length＞5cm,divided the pafients into two groups.The therapeutic group:using subcutanous fistula excision;the control group:using fistula icision.Comparing the healing time,arIus malformation,recurrence rate.Results Therapeutic group 47 cases heal,the healing time was 12 days;no anus malformation;no arms ineontenience.In the control group,the healing time was 23 days;anus malformation 23 cases;anus gas incontenience 12 cases.Conclusion To use subcutanous fistula excision for the longpath low anus fistula has the advantages of short healing time,no anus malformation,less pain,and low reccurrent rate.

Objective To establish an HPLC method for determination of the content of radiosensitizer YABQ and its related substances.Methods Diamonsil C18 column (250 mm ×4.6 mm,5 μm) was used.The mobile phase consisted of methanol-0.1%formic acid (22∶78) and isocratic elution at a flow rate of 1.0 ml/min.The detection wavelength was 266 nm,the temperature of the column was 30℃, and the injection volume was 10 μl.Results The linear range of YABQ was 7-84 μg/ml, r=0.9992.The detection limit was 8 ng (S/N≥3), and the quantitation limit was 24 ng (S/N≥10). According to destructive sample processing, the separation coefficient between the peaks was above 1.5, indicating that this chromatographic method could meet the YABQ monitoring requirements.Conclusion Method validation and destructive testing show that both the precision and specificity are fine with this method, which could be used for quality control of YABQ and its related substances.

Objective To determine the effect of enhanced hand hygiene on the morbidity of ventilator-associated pneumonia (VAP).Methods Clinical studies which were related to enhanced hand cleansing to the risk of VAP,which were published between July 1992 and June 2013 in English or Chinese were retrieved via computer and manual screening.Data were extracted according to appropriate inclusion and exclusion criteria and analyzed with RevMan 5.0 software.Results A total of 6 studies,all of which were performed with well controlled protocol,involving 28 461 mechanical ventilator days and 32 428 mechanical ventilator days were analyzed.The morbidity of VAP was 39.5 days per 1 000 mechanical ventilator days and 19.5 days per 1 000 mechanical ventilator days before and after enhanced hand cleaning,respectively.The methods of enhancing hand hygiene included feasible hand hygiene apparatus,long-term education,supervision and feedback,as well as increased hand cleaning compliance.All 6 eligible studies reported that enhanced hand washing lowered the risk of VAP,with risk reduction ranging from 29.8％ to 65.5％ with a mean reduction value of 50.6％.Meta analysis showed that enhanced hand cleaning could protect patients from VAP with odds ratio (OR) varying from 1.43 to 5.82 [pooled OR=2.23,95％ confidence interval (95％CI) 1.62-3.07,P＜0.000 01].It was showed in funnel chart that bias in the published articles was not significant.Conclusions Enhanced hand hygiene has an effect of prevention of VAP morbidity and is associated with lowered morbidity of VAP.However,the reliability of this conclusion is questionable because of poor quality of these studies.

Objective To analyze the massive explosions and burn at Tianjin Port in 2015 resulted in a mass casualty event,and the entire course of response of a hospital to deal with such major sudden accident in order to find a rational strategy for optimal use of medical resources and reduce the critical mortality.Methods This study was done by a retrospective analysis of data from one trauma center at an academic hospital.Data including outcome,triage,severity and pattern of injuries,patient flow,and medical resources used were obtained by the review of hospital records.Results This disaster caused 165 deaths,8 missing contact,and 797 non-fatal casualties.The Pingjin Hospital admitted 298 casualties,and 29 of them were seriously injured referred to by Tianjin Emergency Medical Center.Excessive triage rate made after transfer to another hospital was 62.07% with 11 of the 29 severely injured patients.Maximum (also the first)surge had 147 injured patients arrived around one hour after incident,the second surge had 31 seriously injured patients occurred around 4 hours after incident.Of them,17 patients needed surgery and 17 patients were admitted to the intensive care unit.Conclusions These data showed that the number of casualties in the first surge was substantially larger than predicted and those casualties had less severe trauma,whereas the number of the injured in the second surge was less but the trauma was more severe.In order to maintain the hospital surge capacity,an effective re-triage and a hospital-wide damage control principle can be used to deal with.

Objective To establish a headspace gas chromatography method for determination of nine residual solvents in grape seed extract. Methods The residual solvents in grape seed extract were separated on DB-WAX column (30 m× 0.45 mm, 0.85 μm) with an FID detector; the injector temperature and the detector temperature was set at 220 ℃ and 250 ℃ , respectively; the chapiter pressure was 27.58 kPa; the containers of headspace injector were in equilibrium for 30 min at 80 ℃ ;the N, N-dimethylformamide was used as the solvent. Results The detected solvents were well separated. Good linear relationship of the benzene and ethanol was obtained within the range of 0.04-0.3,100-750 μg?mL-1 , respectively. Good linear relationships of the hexane, o-xylene, m-xylene, p-xylene, styrene, toluene and 1,2-diethyl benzene solvents were obtained within the range of 0.4-3.0 μg?mL-1 (r≥0.995 8), respectively. The average recoveries (n = 3) of the nine solvents were 96.35%,97.08%,97.31%,89.93%,92.35%,90.65%,88.56%,93.84%,86.51% and the RSDs were 4.38%,2.16%,3.49%, 4.19%,4.80%,4. 83%,4. 70%,5. 00%,4. 39%, respectively. Conclusion The established method is simple, rapid and accurate, which can be used for the determination of residual solvents in grape seed extract and can simultaneously provide scientific basic for quality control.

Objective To explore the labeling method of rat adipose-derived stromal cells,and observe the stem cell characteristics and the activities of EGFP-positive adipose-derived stromal cells (EGFP-ADSCs) in vitro and in vivo.Methods ADSCs were transfected for 12 h with enhanced green fluorescent protein gene (EGFP) carried by lentivirus(Lv-EGFP) vector at different value of MOI (0,5,10,25,50,100,respectively).The rate of EGFP expression and fluorescence intensity were evaluated by flow cytometric analysis and fluorescence microscopy,and cell viability was detected by MTT-test after transfection.Secondly,cells were exposed either to adipogenic medium or osteogenic medium,then stained with Oil Red O and Alizarin Red S.Cell growth was investigated on frozen longitudinal sections when EGFP-ADSCs were injected into acellular nerves to build tissue-engineered peripheral nerves repairing sciatic nerve defects in rats for 1 week in vivo.Results EGFP-positive rate and fluorescence intensity peak at 4 days after transfection.The rate of EGFP expression was 0.13％,31.09％,75.33％,92.66％,96.70％,98.38％ for MOI =0,1,5,25,50,100,respectively.The positive rate between the experimental group and control (MOI =0) existed significantly difference (P ＜ 0.05) ; the difference between MOI =1,5 groups and MOI =25,50,100 groups were also observed (P ＜ 0.05).There was no statistical difference in EGFP-positive rate and cell proliferation activity among MOI =25,50,100 groups (P ＞ 0.05).MOI =25 was chosen as best scheme to transfect ADSCs for subsequent experiments.Osteogenic and adipogenic differentiation for 20 days,orange calcium deposits,orange-red lipid droplets were seen in EGFP-ADSCs after Alizarin red and oil red O staining.At 1 week in vivo,EGFP-ADSCs evenly distributed and became fusiform on frozen longitudinal sections.Conclusion Lv-EGFP transfection does not affect the ADSCs activity and their osteogenic and adipogenic differentiation,so could be as a tracing method for ADSCs-tissue-engineered peripheral nerves repairing nerve defects.

Objective:By comparing the volume% (V% GGOs) of ground glass opacities (GGOs) in high resolution CT (HRCT) of patients with acute paraquat (PQ) poisoning at different time points, its value in the early prognosis of patients with PQ poisoning was analyzed. Methods:The data of patients with PQ poisoning admitted to Department of Respiratory and Critical Care Medicine of Chinese Armed Police Forces from June 2017 to December 2018 were prospectively analyzed. According to the follow-up results after poisoning at 90 days, the patients were divided into the survival group and death group. Three-dimensional reconstruction technology was used to calculate the change of V% GGOs on the 3rd, 5th, and 7th day after poisoning. Chi-square test and One-Way ANOVA of variance were used to compare sex, age, and time of poisoning between the two groups. The Student's t test was used to compare V% GGOs between the two groups at different time points. The receiver operating characteristic curve (ROC) was used to determine the guiding significance of the indicator on the prognosis of patients with PQ poisoning at different time points. Results:A total of 89 patients with PQ poisoning were included in the study, 49 in the survival group and 40 in the death group. There were no statistical differences between the two groups of patients in sex, age, poisoning time, oxygenation index, mean arterial pressure, total bilirubin, blood urea nitrogen, alanine aminotransferase, and aspartate aminotransferase at admission (all P>0.05). The blood PQ concentration (mg/L) in the death group was significantly higher than that in the survival group (6.35 ±0.51 vs 3.49 ±0.21, P= 0.013). On the 3rd, 5th and 7th day after admission, the V% GGOs was significantly higher than that in the survival group (3rd day: 0.062±0.020 vs 0.049±0.007, P= 0.013; 5th day: 0.292±0.130 vs 0.123±0.044, P<0.01; 7th day: 0.334±0.116 vs 0.138±0.034, P=0.019). The area under the ROC curve showed that the prognosis AUC of the 7th day V% GGOs after poisoning was 0.967, the sensitivity was 100% and the specificity was 83.33% when the threshold was 0.16, but the time point was late. On the 5th day after poisoning, the V% GGOs judged the prognosis AUC was 0.842, the sensitivity was 82.35% and the specificity was 89.47% when the threshold was 0.14. On the 3rd day after poisoning, the V% GGOs judged the prognosis AUC was 0.708, the sensitivity was 55.00% and the specificity was 78.95% when the threshold was 0.05. At this time, the sensitivity and specificity were lower than those on the 5th and 7th day. Conclusions:The proportion of ground glass opacity volume in patients with PQ poisoning can be used to evaluate their prognosis, and the best time point is the 5th day after poisoning.

Diabetes kidney disease (DKD) is a serious renal complication of diabetes mellitus, also the main cause of end-stage renal disease (ESRD). Early diagnosis and treatment are very important. Mass spectrometry (MS) can detect biomarkers in blood, urine, tissue and other samples of DKD patients, which has become a research hotspot, and its great significance in early diagnosis, pathogenic research, treatment effect and prognostic evaluation.

Objective To discuss the diagnostic value of a diagnostic strategy combining D-dimer and aortic dissection detection risk score (ADDRS) for patients with acute aortic dissection (AAD). Methods The clinical data of 750 patients with suspected AAD in emergency department of Zhongda Hospital Affiliated to Southeast University from January 2016 to January 2018 were retrospectively analyzed, including medical history, gender, age, chief complaint, physical examination, diagnostic imaging data and D-dimer levels on admission. ADDRS = 0 was defined as low risk group, ADDRS = 1 as medium risk group, ADDRS≤1 as non-high risk group,whereas ADDRS > 1 as high risk group. The clinical characteristics of AAD and non-AAD patients, ADDRS, D-dimer, and the diagnostic ability of D-dimer (the cutoff value of 500 μg/L) for AAD in different risk groups were observed. Results AAD was diagnosed in 79 of 750 (10.53%) patients. Of the 256 (34.13%) patients in low risk group, 5 patients were diagnosed with AAD. The medium risk group had 337 (44.93%) patients, including 44 cases with AAD. The high risk group had 157 (20.93%) patients, including 30 cases with AAD. In AAD patients, the proportion of male and hypertension, the incidence of ADDRS risk markers (including abrupt onset of pain, severe pain intensity, ripping or tearing pain, pulse deficit or systolic blood pressure differential of upper limb, focal neurological deficit, recent aortic manipulation, known thoracic aortic aneurysm) and the D-dimer levels in AAD group were significantly higher than those of non-AAD patients [male: 82.28% (65/79) vs. 59.76% (401/671), hypertension: 81.01% (64/79) vs. 41.43% (278/671), abrupt onset of pain: 78.48% (62/79) vs. 39.94% (268/671), severe pain intensity: 78.48% (62/79) vs. 50.52% (339/671), ripping or tearing pain: 32.91% (26/79) vs. 0.75% (5/671), pulse deficit or systolic blood pressure differential of upper limb: 15.19% (12/79) vs. 0.15% (1/671), focal neurological deficit: 7.59% (6/79) vs. 1.64% (11/671), recent aortic manipulation: 6.33% (5/79) vs. 0.30% (2/671), known thoracic aortic aneurysm: 15.19% (12/79) vs. 0.30% (2/671), D-dimer (μg/L): 1 160 (588, 3 340) vs 135 (56, 478), all P < 0.05], the proportion of diabetics was significantly lower than that of non-AAD patients [7.59% (6/79) vs. 18.78% (126/671), P < 0.05]. The positive predictive values of D-dimer for AAD diagnosis in the low risk group and the non-high-risk groups (including low and medium risk groups) were lower than that in the high risk group (8.62%, 26.32% vs. 40.91%), the negative predictive values of D-dimer were higher in the low risk group and non-high-risk groups than that in the high risk group (100.00%, 99.05% vs. 96.70%), missed diagnosis rates were higher than that in high risk group (0, 0.95%, vs. 3.30%). Conclusion In the high risk group, D-dimer≥500 μg/L is helpful for diagnosis of AAD; and in low risk group or non-high-risk group, D-dimer < 500 μg/L can efficiently and accurately exclude AAD.