Objective To explore the effects of lead acetate on free radicals and lipid peroxidation in the cerebral cor?tex, cerebellum, and hippocampus in rat brains. Methods SD rats (n=48), who were just weaned, were randomly divided in?to 4 groups base on their weight. Then the rats were fed with lead acetate in drinking water at the final concentrations of 0 mg/L (deionized water), 200 mg/L, 400 mg/L, 800 mg/L respectively. Blood lead level as well as the hydroxyl free radical inhibiting activity, the levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA) in cerebral cortex, cerebellum, and hippocam?pus were measured 60 days after lead contamination in water. Results Upon lead exposure, blood lead levels increased sig?nificantly as compared with the control. The hydroxyl free radical inhibiting activity in cerebral cortex, cerebellum, and hip?pocampus decreased significantly in a dose dependent manner of lead(P < 0.05). And they all correlated negatively with blood lead level (r=-0.505,-0.414,-0.448, P<0.05). By contrast, blood lead level was positively correlated with H2O2 and MDA in these brain tissues (r=0.301, 0.411, 0.378, and 0.404, 0.324, 0.510,P < 0.05). Conclusion Lead exposure can lead to lipid peroxidation of rat brain tissues through inducing free radicals.

Aim To investigate the effect of salvianolic acid B (Sal B)on c-Jun N-terminal kinase (JNK)ac-tivation and apoptosis of INS-1 cells induced by inter-mittent high glucose.Methods INS-1 cells were pre-incubated with Sal B for 24 h,followed by exposure to intermittent high glucose (IHG,11.1 mmol·L-1 12 h,33. 3 mmol·L-1 12 h)for 72 h.Cell viability was assessed by MTT assay and cell apoptosis was evalua-ted by flow cytometry.Glucose induced insulin secre-tion capacity and intracellular reactive oxygen species (ROS)contents were measured by enzyme linked im-munosorbent assay (ELISA)and a fluorescent probe DCFH-DA,respectively.Levels of JNK activation and PDX-1 protein expression were determined by Western blot analysis.Results Sal B significantly alleviated IHG-induced cell injury and apoptosis,with glucose induced insulin secretion capacity improved evidently (P<0.05 or P<0.01).Preincubation with Sal B no-tably decreased intracellular ROS and JNK activation in INS-1 cells,while the level of PDX-1 protein was in-creased markedly (P<0.05 or P<0.01 ).Conclu-sion Sal B is capable of ameliorating IHG-induced cell injury and apoptosis in INS-1 cells,which might be derived from suppression of JNK activation and up-regulation of PDX-1 protein expression.

Objective To evaluate the effect of pre-cut-endoscopic mucosa resection of colorectal laterally spreading tumor. Methods 65 patients with LST were enrolled from January 2014 to February 2014. LST was detected by chromoendoscopy and NBI combined with magnifying endoscopy technique. The size, site, morphological features, were observed and the histopathological features of the specimen of LST was analyzed. All the 65 LSTs were resect by pre-cut-EMR. The clinical results including enbloc resection rate, all bloc resection rate, procedure time, complication and recurrence rates were retrospectively evaluated. Results All the 65 LSTs lesions ranged from 2.0 cm to 5.0 cm, with a mean diameter of (2.4 ± 1.7) cm. The site of 65 LSTs was in rectum 28 (43.1 %), 11 LSTs in sigmoid colon (16.9 %), 6 LSTs in descending colon (9.2 %), 2 LSTs in splenic flexure of colon (3.1 %), 9 LSTs in transverse colon (13.8 %), 4 LSTs in Hepatic flexure of colon (6.2 %), 2 LSTs in ascending colon(3.1 %), and 3 LSTs in cecum (4.6 %). Morphology of 23 LSTs were homogeneous granular type (35.4 %), 27 LSTs were mixed non-granular type (41.5 %), 13 LSTs were flat elevated type (20.0 %), and 2 LSTs were pseudo-depressed type (3.1 %). The histopathological diagnoses of LST included 12 tubular adenoma (18.5 %), 19 villous-tubular adenoma (29.2 %), 26 villous adenoma (40.0 %), 7 advanced intraepithelial tumor (10.7 %), 1 intramucosal carcinoma (1.5 %). Enbloc resection was achieved in 65 patients (100.0 %) with a mean operation time of (18.0 ± 11.7) min. 5 cases were bleeding during the operation (7.7 %), 1 case was bleeding 7 days after operation (1.5 %), no perforation was happened. 65 patients were followed up for 3 ~ 12 months, and no local recurrence was found. Conclusion Pre-cut-endoscopic mucosal resection an effective and safe therapy for colorectal LST larger than 2.0 cm.

OBJECTIVETo investigate the change pattern of primary and secondary school teachers' work ability with the changes in their mental workload.

METHODSA total of 901 primary and secondary school teachers were selected by random cluster sampling, and then their mental workload and work ability were assessed by National Aeronautics and Space Administration-Task Load Index (NASA-TLX) and Work Ability Index (WAI) questionnaires, whose reliability and validity had been tested. The effects of their mental workload on the work ability were analyzed.

RESULTSPrimary and secondary school teachers' work ability reached the highest level at a certain level of mental workload (55.73< mental workload ≤ 64.10). When their mental workload was lower than the level, their work ability had a positive correlation with the mental workload. Their work ability increased or maintained stable with the increasing mental workload. Moreover, the percentage of teachers with good work ability increased, while that of teachers with moderate work ability decreased. But when their mental workload was higher than the level, their work ability had a negative correlation with the mental workload. Their work ability significantly decreased with the increasing mental workload (P < 0.01). Furthermore, the percentage of teachers with good work ability decreased, while that of teachers with moderate work ability increased (P < 0.001).

CONCLUSIONToo high or low mental workload will result in the decline of primary and secondary school teachers' work ability. Moderate mental workload (55.73∼64.10) will benefit the maintaining and stabilization of their work ability.

Faculty ; statistics & numerical data ; Humans ; Occupational Health ; Reproducibility of Results ; Sampling Studies ; Schools ; Stress, Psychological ; psychology ; Surveys and Questionnaires ; Work ; psychology ; Workload ; psychology

OBJECTIVE: To analyze the effect of bronchoalveolar lavage( BAL) on respiratory function and arterial blood gas of pneumoconiosis patients. METHODS: The published literatures about relationship between BAL and respiratory function and arterial blood gas in pneumoconiosis patients from China National Knowledge Internet,Wanfang Database,Chinese Biomedical Literature Database,Chinese Journal Database,Pub Med,Embase,Web of Science Database and the Cochrane Library Database and so on from 2000 to 2016 were retrieved,collected,and screened by using bibliometric method. The data was analyzed by Meta analysis with the help of Rev Man 5. 0 software. The weighted mean difference( MD) and 95%confidence interval( CI) were calculated on selected literatures. RESULTS: A total of 20 articles were selected and used.The forced vital capacity( FVC)( MD = 0. 21,95% CI: 0. 04-0. 37),the forced expiratory volume in one second( FEV1)( MD = 0. 12,95% CI: 0. 01-0. 23),the maximum ventilatory volume( MD = 10. 73,95% CI: 3. 48-17. 98) and partial pressure of oxygen( MD = 8. 85,95% CI: 0. 30-17. 39) in the patients after BAL were higher than before( P < 0. 05),while the partial pressure of carbon dioxide in artery( MD =-3. 58,95% CI:-5. 61--1. 55) decreased( P < 0. 01).Both of the FEV1/FVC( MD = 2. 08,95% CI:-6. 27-10. 43) and the FEV1%( MD = 0. 86,95% CI:-0. 55-2. 28)had not statistically significance before and after BAL( P > 0. 05). CONCLUSION: BAL can improved respiratory function and arterial blood gas in pneumoconiosis patients.

OBJECTIVETo analyze the risk factors of carcinogenesis of large colorectal polyps (diameter ≥ 10 mm) found by colonoscopy.

METHODSClinicopathological and follow-up data of 418 consecutive patients who were diagnosed as colorectal polyps with diameter≥10 mm by colonoscopy at two endoscopy centers of the Affiliated Wuxi Second People's Hospital, Nanjing Medical University (n=207) and Zhongshan Hospital, Fudan University (n=211) from January 2015 to December 2016 were retrospectively collected. High-grade intraepithelial neoplasia and cancer were defined as malignancy in this study. Chi square test was used for univariate analysis, and logistic regression was used for multivariate analysis (in patients with multiple polyps, if the pathological findings were all low grade intraepithelial neoplasia, one polyp with the largest diameter was selected to enter the model; in patients with high grade intraepithelial neoplasia, one polyp of high grade intraepithelial neoplasia with the largest diameter was selected to enter the model). Associated risk factors of malignancy were analyzed.

RESULTSAmong the 418 patients, 278(66.5%) were male and 140(33.5%) were female, with mean age of (58.7±10.2) (range 15-87) years old. Of 398 patients undergoing endoscopic treatment with resected 456 polyps, 142 cases with 150 polyps were malignant, including 134 polyps of high-grade intraepithelial neoplasia and 16 polyps of intra-mucosal cancer. The other 20 patients showed negative elevation signs after endoscopic submucosal injection and were transferred to surgery, of whom 20 polyps were resected. Histological examination of these 20 polyps indicated invasive cancer. Univariate analysis showed that age ≥ 50 years [40.5% (150/370) vs. 25.0% (12/48), χ² =4.323, P=0.041], multiple polyps [77.5%(31/40) vs. 34.7%(131/378), χ² =12.900, P=0.001], polyp locating at rectum [59.0%(36/61) vs. 32.3%(134/415), χ² =22.736, P=0.000], polyp diameter ≥31 mm [74.1%(20/27) vs. 33.4%(150/449), χ² =36.493, P=0.000] and tubular villous adenoma [67.4%(120/178) vs. 16.8%(50/298), χ² =71.810, P=0.000] were associated with malignancy. Multivariate analysis showed that age ≥ 50 years(OR=2.473, 95%CI:1.209-5.058, P=0.013), multiple polyps (OR=2.472, 95%CI: 1.300-4.702, P=0.006), polyp locating at rectum (OR=1.253, 95%CI: 1.091-1.439, P=0.001) and the polyp diameter ≥31 mm (OR=1.500, 95%CI:1.196-1.881, P=0.000) were independent risk factors for malignancy of large colorectal polyps. The mean follow-up time was (9.6±4.2) months. During the follow-up period, 86 patients (20.5%) who received endoscopic resection developed recurrent adenoma which all were successfully removed by colonoscopic polypectomy. Two patients(0.5%) developed colon cancer 6 months after endoscopic resection and both underwent radical surgery and chemotherapy. Their previous pathology from endoscopic resection was tubular villous adenoma and high grade intraepithelial neoplasia. All the patients were alive during the follow-up period.

CONCLUSIONSAge ≥50 years old, multiple polyps, polyps locating at rectum and polyps with diameter ≥ 31 mm are the risk factors of malignancy. Emphasized examination should be recommended for those with the above mentioned risk factors to avoid missed diagnosis and misdiagnosis. The choice of endoscopic treatment must be reasonable for curative resection.