Objective:To establish a direct and rapid method for direct determination of arsenic in urine by inductively coupled plasma mass spectrometry (ICP-MS).Methods:The newly collected urine samples were diluted directly with pure water without pretreatment. The total arsenic content in urine was determined directly by ICP-MS. The method was studied from the aspects of linear range of standard curve, correlation coefficient, detection limit, precision and accuracy.Results:The concentration of arsenic in urine was in the range of 0 - 200 μg/L, the ratio of arsenic to germanium was in good linear relationship with arsenic concentration, the correlation coefficient was 0.999 5 - 0.999 9 ( n = 6), the lowest qualitative and quantitative detection limits of arsenic in urine were 0.66 and 1.94 μg/L(the sampling volume was 0.50 ml), respectively. Five urine samples with different arsenic concentrations were tested for intrabatch and inter batch precision with RSD ranging from 1.51% to 6.84% and 1.85% to 5.03%, respectively. The total arsenic of urine samples from the Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention was determined with this method, and the results were within the range of the published consensus value. The recovery rate of 4 urine samples with arsenic concentration range 3.19 - 89.36 μg/L was 99.25% - 103.67%, and the total average recovery rate was 101.51%. Conclusions:Application of ICP-MS method to detect arsenic content in urine, urine samples can be directly injected to realize the automation of injection, detection process and result analysis. The test parameters such as sensitivity, precision and accuracy of the method meet the requirements of the development of biological sample detection method and are suitable for rapid and direct determination of total arsenic in urine.

Objective:To evaluate the role of hypoxia-inducible factor-1α (HIF-1α) in hydrogen-induced inhibition of lipopolysaccharide (LPS)-induced inflammatory responses in mouse macrophages.Methods:The mouse RAW264.7 macrophages cultured in vitro were divided into 4 groups ( n=24 each) according to the random number table method: control group (C group), LPS group (L group), hydrogen-rich solution plus LPS group (H+ L group), and hydrogen-rich solution plus LPS plus HIF-1α inhibitor 2-methoxyestradiol (2ME2) group (H+ L+ M group). LPS 1 μg/ml was added, and the cells were incubated for 6 h in group L. In group L+ H, LPS was added first, the medium was changed to 0.6 mmol/L hydrogen-rich solution, and cells were incubated for 6 h. In group H+ L+ M, 2ME2 10 μmol/L was given first, cells were then incubated for 30 min, LPS and hydrogen-rich solution were added, and cells were incubated for 6 h. Western blot was used to determine the expression of HIF-1α, Beclin-1, Bcl-2/E1B-19 kDa interacting protein 3 (BNIP3) and LC3.Enzyme-linked immunosorbent assay was used to detect the concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β in the supernatant.The number of autophagosomes was observed using a transmission electron microscope. Results:Compared with group C, the concentrations of TNF-α, IL-6 and IL-1β in the supernatant were significantly increased, the expression of HIF-1α, Beclinl and BNIP3 in macrophages was up-regulated, the ratio of LC3Ⅱ/LC3Ⅰ was increased, and the number of autophagosomes was increased in group L ( P<0.05). Compared with group L, the concentrations of TNF-α, IL-6 and IL-1β were significantly decreased, the expression of HIF-1α, Beclin-1 and BNIP3 in macrophages was up-regulated, LC3Ⅱ/LC3Ⅰ ratio was increased, and the number of autophagosomes was increased in group H+ L ( P<0.05). Compared with group H+ L, the concentrations of TNF-α, IL-6 and IL-1β in the supernatant were significantly decreased, the expression of HIF-1α, Beclin-1, and BNIP3 in macrophages was down-regulated, and the ratio of LC3Ⅱ/LC3Ⅰ was decreased, and the number of autophagosomes was decreased in group H+ L+ M ( P<0.05). Conclusion:HIF-1α-mediated activation of autophagy is involved in the process of hydrogen-induced inhibition of LPS-induced inflammatory responses in mouse macrophages.

Objective:To investigate the clinical effect of minimally invasive surgery in the treatment of professional drivers with lumbar disc herniation.Methods:126 patients with lumbar disc herniation admitted to hospital from June 1, 2015 to December 30, 2018 were selected and divided into observation group (59 cases treated by percutaneous transforaminal endoscopy) and control group (67 cases treated with conventional conservative treatment) according to the treatment methods. The Visual Analogue Scale (VAS) and Japanese Orthopaedic Association Scores (JOA) before and after treatment were analyzed retrospectively. Length of stay, time out of bed, hospitalization expenses and recurrence rate were evaluated. The measurement data was expressed by ± s, the comparison between groups was performed by t test, and the count data were analyzed by descriptive analysis. Results:Before treatment, there was no significant difference in gender, age, VAS score and JOA score between the two groups ( P>0.05) . After treatment, compared with the control group, the VAS score of the observation group was lower, the JOA score was higher, the time out of bed was shorter, the average hospitalization time was reduced, the average hospitalization cost was higher, and the recurrence rates after Six months and one year were lower in the observation group, the differences were statistically significant ( P<0.05) . Conclusion:The clinical effect of percutaneous transforaminal endoscopic treatment is better than that of conventional conservative treatment for driver＇s lumbar disc herniation.

Objective:To investigate the clinical effect of minimally invasive surgery in the treatment of professional drivers with lumbar disc herniation.Methods:126 patients with lumbar disc herniation admitted to hospital from June 1, 2015 to December 30, 2018 were selected and divided into observation group (59 cases treated by percutaneous transforaminal endoscopy) and control group (67 cases treated with conventional conservative treatment) according to the treatment methods. The Visual Analogue Scale (VAS) and Japanese Orthopaedic Association Scores (JOA) before and after treatment were analyzed retrospectively. Length of stay, time out of bed, hospitalization expenses and recurrence rate were evaluated. The measurement data was expressed by ± s, the comparison between groups was performed by t test, and the count data were analyzed by descriptive analysis. Results:Before treatment, there was no significant difference in gender, age, VAS score and JOA score between the two groups ( P>0.05) . After treatment, compared with the control group, the VAS score of the observation group was lower, the JOA score was higher, the time out of bed was shorter, the average hospitalization time was reduced, the average hospitalization cost was higher, and the recurrence rates after Six months and one year were lower in the observation group, the differences were statistically significant ( P<0.05) . Conclusion:The clinical effect of percutaneous transforaminal endoscopic treatment is better than that of conventional conservative treatment for driver＇s lumbar disc herniation.

Objective: To compare the weight loss and metabolic profile between a continuous energy-restricted diet and intermittent fasting diet in order to present an optimal nutritional weight reduction method for obese people in China. Methods: Sixty overweight or obese adults were selected and divided into two groups as the continuous energy-restricted diet group and the intermittent fasting diet group. Height, weight, waist circumference, body mass index(BMI), body fat, change of visceral fatarea, fasting glucose(FPG), triglyceride(TG), total cholesterol(TC), high density cholesterol(HDL), low density cholesterol(LDL), glutamic pyruvicaminotransferase(AST), signglutamic pyruvic transaminase(ALT), gamma-glutamyltranspeptidase(GGT), alkalinephosphatase (ALP), fasting insulin level(FINS) and HOMA-IR were assessed at baseline and 8 weeks after weight loss methods carried. Results: Both continuous energy-restricted diet and intermittent fasting diet resulted improvement on body shape indexes and a significant decrease in weight, waist circumference, BMI, body fat, visceral fat area and skeletal muscle(P<0.01)at 8 weeks. Both groups experienced improvements in biochemical outcomes and metabolic indicators at 8 weeks. A significant reduction in TC, AST, ALT, GGT, ALP, FINS and HOMA-IR(P<0.01 or P<0.05)were observed in continuous energy-restricted diet group. And a significant decline in TC, LDL, HDL, AST, ALT, GGT, ALP, FINS and HOMA-IR were observed in intermittent fasting diet group(P<0.01 or P<0.05). HDL was found significantly reduced in intermittent fasting diet group as compared with continuous energy-restricted diet group(P<0.01) at 8 weeks, however, there were no difference in weight loss, waist circumference, BMI, body fat, visceral fat area and other metabolic indicators at 8 weeks(P>0.05). Conclusion Both intermittent fasting diet and continuous energy-restricted diet have a similar effect on weight loss and metabolic indexes like blood glucose, HOMA-IR and blood lipid, but intermittent fasting diet can more significantly decrease HDL level.

Objective: To investigate the incidence of neck and shoulder pain among dentists in several hospitals in Tianjin, China and the main factors for the onset of neck and shoulder pain, and to provide ideas for reducing the incidence rate of neck and shoulder pain in dentists. Methods: In December 2018, a total of 140 dentists from General Hospital of Tianjin Medical University, The Second Hospital of Tianjin Medical University, and Tianjin Stomatological Hospital were selected as respondents. A self-designed questionnaire was used to investigate the incidence rate of neck and shoulder pain among the dentists and related influencing factors. A total of 140 questionnaires were distributed, among which 129 (96.9%) were usable questionnaires. The questionnaire contained the questions on personal information and conditions of neck and shoulder pain. The continuous data were expressed as Mean±SD, and the categorical data were expressed as percentage (%) . The multivariate logistic regression analysis was used to investigate influencing factors. Results: Among the 129 respondents, 120 (93.02%) had neck and shoulder pain. The prevalence rates of neck pain alone, shoulder pain alone, and neck and shoulder pain were 34.9% (45/129) , 31.8% (41/129) , and 26.3% (34/129) , respectively. Certain factors, such as age, sex, exercise, working time, bad sitting posture, inappropriate seat, and engagement in periodontology or orthodontics, had a linear relationship with the incidence rate of neck and shoulder pain among the respondents (P<0.05) . Conclusion There is a high incidence rate of neck and shoulder pain among the dentists in some hospitals in Tianjin. Dentists should be encouraged to control the number of consultations, adjust the sitting posture during work, arrange working hours reasonably, and strengthen physical exercise, so as to reduce the incidence rate of neck and shoulder pain.

Objective To investigate the effects of a standard food-based low calorie diet and meal replacements on compliance,weight loss,and glycolipid metabolism in obese patients,and to provide an optimal nutritional weight reduction method for obese individuals in China.Methods Height,weight,waist circumference,body mass index (BMI),body fat,visceral fat in low calorie diet group (n =23) and meal replacements group (n =17) were assessed at baseline,4 and 8 weeks after the intervention.Fasting plasma glucose (FPG),triglyceride (TG),total cholesterol (TC),high density lipoprotein-cholesterol (HDL-C),low density lipoprotein-cholesterol (LDL-C),aspartate aminotransferase (AST),alanine transaminase (ALT),gamma-glutamyl transpeptidase (GGT),alkaline phosphatase (ALP),fasting insulin (FINS),and homeostasis model assessment for insulin resistance (HOMA-IR) were assessed at both baseline and 8 weeks after the intervention.Results Both low calorie diet and meal replacements led to significant decreases in body weight,waist circumference,BMI,body fat,and visceral fat(all P＜0.01) after 4 and 8 weeks.Body fat (P＜ 0.01) and total body water (P＜ 0.05) in low calorie diet group were decreased more obviously compared with those in meal replacements group at 4 weeks.However,there were no difference in all these parameters between two groups at 8 weeks (P＞0.05).Both groups experienced improvements in biochemical outcomes and metabolic indicators.TG,AST,ALT,GGT,ALP,FINS,and HOMA-IR levels were all decreased (P＜0.05 or P＜0.01) while HDL-C level was increased (P＜0.01) 8 weeks after standard food-based low calorie diet.FPG,TG,TC,LDL-C,AST,ALT,ALP,FINS,and HOMA-IR levels were declined 8 weeks after meal replacements(P＜0.05 or P＜0.01).TC,LDL-C,and ALT levels were more evidently to reduce in meal replacements group compared with low calorie diet group.Conclusions Present data suggest that meal replacements and low calorie diet may have a similar effect on weight loss,while meal replacements seems to obtain a better metabolic results.

Objective To compare the efficacy of adriamycin chemo-ganglionectomy and radiofre-quency thermocoagulation ( RFT ) of semilunar ganglion in treating craniofacial postherpetic neuralgia ( PHN) . Methods A total of 95 patients with PHN in the areas innervated by maxillary and mandibular divisions of trigeminal nerve, aged 55-90 yr, with the course of disease 6 months-3 yr, were divided into 2 groups using a random number table method: adriamycin chemo-ganglionectomy group ( ADM group, n=48) and RFT group ( n=47) . Hartel anterior approach to puncture was performed via the foramen ovale un-der the guidance of CT in two groups. In group ADM, 0. 5％ adriamycin 2. 5 mg ( 0. 5 ml) was injected via the foramen ovale, and RFT of gasserian ganglion was performed in group RFT. Visual Analog Scale (VAS) and the short-form McGill pain questionnaire (SF-MPQ) scores were evaluated before and after treatment. The rate of effective treatment was calculated, and treatment-related complications were recor-ded. Results Compared with group RFT, no significant change was found in VAS or SF-MPQ scores be-fore treatment, VAS and SF-MPQ scores were increased and the rate of effective treatment was decreased at 1 and 7 days after treatment, VAS and SF-MPQ scores were decreased and the rate of effective treatment was increased at 6 and 12 months after treatment, the incidence of facial numbness, hypoesthesia, masti-catory muscle weakness and weakened corneal reflex was decreased in group ADM ( P<0. 05) . Conclusion Compared with semilunar ganglion RFT, the long-term efficacy of adriamycin chemo-ganglionectomy of semilunar ganglion in treating craniofacial PHN is enhanced, and the safety is higher.

Objective To evaluate the effect of application of pulsed radiofrequency to dorsal root ganglia on activation of spinal astrocytes in a rat model of neuropathic pain (NP).Methods Eighty male Sprague-Dawley rats,aged 6-8 weeks,weighing 200-250 g,were divided into 4 groups (n=20 each) using a random number table method:sham operation group (group Sham),group NP,pulsed radiofrequency group (PRF group) and sham pulsed radiofrequency group (group SPRF).NP was induced by chronic constriction injury (CCI).The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 1 day before CCI and 1,7,14 and 21 days after CCI.Four rats were sacrificed at 1 day before CCI and 14 and 21 days after CCI,and the L4.6 segments of the spinal cord were harvested to detect the expression of glial fibrillary acidic protein (GFAP) and interleukin-1beta (IL-1β) by Western blot.Results Compared with group Sham,the MWT was significantly decreased and the TWL was shortened at each time point after CCI,and the expression of GFAP and IL-1β was up-regulated at 14 and 21 days after CCI in NP,PRF and SPRF groups (P＜0.05).Compared with group NP,the MWT was significantly increased and the TWL was prolonged at 14 and 21 days after CCI (P＜0.05),and the expression of GFAP and IL-1β was down-regulated at 14 and 21 days after CCI in group PRF (P＜0.05),and no significant change was found in the parameters mentioned above in group SPRF (P＞0.05).Conclusion The mechanism by which pulsed radiofrequency reduces NP is probably related to inhibiting spinal astrocyte activation in rats.

We have evaluated the plague epidemic situation in the Three Rivers Source Region,Qinghai Province in recent 20 years to provide the basis for revising the plague prevention countermeasures.We have analyzed the time distribution and the plague epidemic situation between animals and human beings during twenty years in the Three Rivers Source Region,Qinghai Province by describing epidemiology.The animal plague in the natural source of Marmot plague was extremely serious in the Three Rivers Source Region during the past 20 years.It mainly distributes in Yushu State and Tanggula County,Germu City and the serious season ran through the whole period of marmot camp ground activities and the peak was between June and August.Human plague epidemic took place between May and October each year and reached its peak between July and September.The peak covered about 41.67％ at most.It mainly endemic distributes in Nangqian and Xinghai Country.During the past 20 years,we have totally found 14 human plague epidemics in the Three Rivers Source Region,among which 48 cases took place and there were deaths of 17 cases.The fatality rate was 35.42％.The lung type was the majority among 48 cases,which startde with the glandular type.During the past 20 years the plague epidemic has been active and the animal plague epidemic broke out continuously in the Three Rivers Source Region,Qinghai Province.The variety of animals and insects infected the plague epidemic was increasing.The human plague epidemics is most serious with high fatality rate,but it is on the decline as a whole.