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Objective @#To investigate the effects of the exposure of sludge from sewage treatment plants and microplastic extracted from sludge on the oxidative stress levels in zebrafish, so as to put insights into the research into the impact of sludge and microplastics on human health. @*Methods @#Adult wild AB zebrafish were exposed to five groups of sludge (0, 12.5, 25, 50 and 75 g/L) and four groups of microplastics extract from sludge (0, 240, 480, 960/L), with 24 zebrafish in each group. The color, activity and death of zebrafish were observed every day. The contents of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and malondialdehyde (MDA) were detected 0 h, 24 h, 48 h, 72 h, 96 h and 7 d post-exposure. A two-factor ANOVA was used to analyze the effects of different concentrations and time of exposure on the indicators above. @*Results @#Under 75 g/L sludge exposure, zebrafish began to show mortality at 72 h and all died after 7 d. The zebrafish in the other sludge groups and all microplastic groups had normal color and activity, and no mortality was observed. Sludge concentration interacted with exposure time to affect SOD, CAT, GSH and MDA (P<0.05). With increasing sludge concentration and exposure time, SOD decreased, MDA increased, CAT increased first and then decreased, GSH decreased first and then increased, and GSH continued to decrease since 24 h in the 75 g/L group. The microplastic concentration interacted with exposure time to affect SOD and GSH (P<0.05), but not CAT or MDA (P>0.05). With increasing microplastic concentration and exposure time, SOD and MDA increased, CAT increased first and then decreased, the GSH was slightly increased at 24 h and decreased after 72 h.@*Conclusion @#Both sludge and microplastics extracted from sludge can induce oxidative stress damage in zebrafish, and exposure time and concentration can interact to affect oxidative stress levels. The microplastics extracted from sludge have less effect on oxidative stress levels in zebrafish than sludge.
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Objective@#To understand the current situation and associated factors of myopia among primary school students, and to provide scientific basis for prevention and control of myopia among primary school students.@*Methods@#In Gansu, Guangdong, Guangxi, Guizhou, Liaoning, Shandong, Shanxi and other provinces, 1 prefecture was selected, and a number of primary schools were selected from each region. All the students in the class were selected as the object of this survey. A total of 8 365 middle school students were examined for their eyesight, and the data of general population economic indicators and natural environment indicators were obtained through the statistical yearbook of various provinces and cities. The influencing factors of primary school students myopia were analyzed by chi-square test and multivariate Logistic regression.@*Results@#Univariate analysis showed that different provinces and different sex, different nationalities, different grade, parents average salary, sunshine duration, air temperature, altitude, longitude, latitude, different economic zone(χ2=116.22, 18.08, 26.33, 1 059.04, 14.86, 10.28, 16.95, 10.01, 23.15, 29.43, 88.14, P<0.05). Multivariate analysis results showed that gender, grade, sunshine duration, longitude were risk factor for poor vision(OR=1.31, 1.71, 1.45, 1.54, P<0.05); Economic zone and parents salary were protective factors for poor eyesight of students (OR=0.65, 0.86, P<0.05).@*Conclusion@#Myopia of primary school students is affected by a variety of factors, economic and social factors and natural environmental factors have an impact on the screening.
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Objective @#To investigate the combined effects of triclosan（TCS）and PCB153 on the activity of superoxide dismutase（SOD）and the concentration of malondialdehyde（MDA）in zebrafish liver.@*Methods @#Adult zebrafish were exposed to a series of concentrations of TCS,and the mortality in each group was observed and recorded during the acute toxicity test process. The concentrations in subsequent combined exposure experiments were arranged on the basis of the 96 h-LC50. The factorial design was used to determine the concentrations of combined exposure groups between TCS（0,0.125,0.5 μmol/L）and PCB153（0,0.05,0.2 μmol/L）. After 5,10 and 14 days of exposure,the zebrafish livers were dissected and frozen in each group. The potential interactions of these two compounds were analyzed according to the results of the SOD and MDA.@*Results @#The 96 h-LC50 of TCS exposed to adult zebrafish was 2.64 μmol/L（95%CI：2.37-2.89 μmol/L）. After 5 days of exposure,combined exposure to 0.5 μmol/L TCS+0.2 μmol/L PCB153 caused lower liver SOD activities than single exposure groups and the control group（P<0.05）. After 10 days of exposure,combined exposure to 0.125 μmol/L TCS+0.05 μmol/L PCB153,0.5 μmol/L TCS+0.05 μmol/L PCB153 caused lower liver SOD activities than single exposure groups and the control group（P<0.05）. After 14 days of exposure,combined exposure to 0.5 μmol/L TCS+0.05 μmol/L PCB153,0.5 μmol/L TCS+0.2 μmol/L PCB153 caused higher liver SOD activities than single exposure groups and the control group（P<0.05）. There was an interactive effect between TCS and PCB153 on the liver SOD activity in zebrafish（P<0.05）. There was no significant effect of MDA content in each group.@*Conclusion @#Combined exposure to TCS and PCB153 could enhance （inhibit first） the liver SOD activities in zebrafish,and the interaction was synergistic.
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Objective To compare the effect of immediate implantation and delayed implantation on the surrounding tissue.Methods The clinical data of 98 cases of anterior teeth with single implant repair were analyzed retrospectively,and they were divided into study group (n =50) and control group (n =48) according to the method of implantation.The patients in the study group were implanted in the tooth socket immediately after the minimally invasive tooth extraction,and the patients in the control group were implanted after 12-16 weeks of minimally invasive extraction.All the two groups were repaired in coronal at 6 months after implantation.The success rate of implant,implant bone resorption,periodontal probing depth,gingival bleeding index,plaque index and red aesthetic score were compared between the two groups.Results The success rate was 100％ in the two groups after 12 months,the difference was not statistically significant(P ＞ 0.05).The implant surrounding bone absorption in the study group was lower than that in the control group,the differences were statistically significant (t =2.132,2.241,2.421,all P ＜ 0.05).At the end of 3 and 6 months,the depth of probing in the study group were significantly lower than those in the control group (t =2.019,2.307,all P ＜ 0.05),and the red aesthetic score in the study group was significantly higher than that in the control group,the differences were statistically significant [(7.97 ± 1.12) points vs.(6.82 ± 1.03) points,(8.65 ± 1.14) points vs.(7.42 ± 1.07) points,t =2.012,2.137,all P ＜ 0.05].The modified sulcus bleeding index and plaque index had no statistically significant differences between the two groups (all P ＞ 0.05).Conclusion The clinical effect of immediate implant restoration of anterior teeth is better than delayed implantation.
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BACKGROUND:Occurrence and development of diabetic complications is closely related to the severity of oxidative stress imbalance in the body. OBJECTIVE:To investigate the effect of embryonic stem cel s on oxidative stress response of rats with diabetic nephropathy. METHODS:Primarily cultured rat embryonic stem cel s were observed for cel morphology and surface antigen detection. Sprague-Dawley rats were divided into experimental group (two injections of embryonic stem cel s via the tail vein), model group (injection of the same volume of PBS), and normal control group (with no modeling, intraperitoneal injection of sodium citrate-citrate buffer). In the former two groups, the rats were intraperitoneal y injected sodium citrate-citrate buffer diluted streptozotocin to establish diabetic nephropathy models before treatment. At 5 weeks after the last injection, blood glucose level, renal function indicators (urine protein/urine creatinine, blood urea nitrogen and serum creatinine) were tested in each group;contents of malondialdehyde and protein carbonyl were detected in the kidney;the expression level of superoxide dismutase was detected by western blot assay. RESULTS AND CONCLUSION:The embryonic stem cel s were oval or round, with clear boundary and good refraction, and highly expressed Oct-4 and SSEA-1. Compared with the control group, renal biochemical indicators, malondialdehyde and protein carbonyl contents were significantly increased, while the expression level of superoxide dismutase was decreased dramatical y in the model group and experimental group (P<0.05);compared with the model group, the renal biochemical indicators, malondialdehyde and protein carbonyl contents were dropped significantly in the experimental group, but the expression of superoxide dismutase was significantly rebounded (P<0.05). Taken together, embryonic stem cel s can reverse the occurrence and development of diabetic nephropathy by inhibiting oxidative stress in progress.
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Objective To explore the effect of modified Zexie Decoction on renal aquaporin-2 (AQP2) expression in high-salt hypertensive rat. Methods Hypertensive rats model was established by feeding rat with 8%high salt. Rats (n=50) were divided into model group, modern medicine group, traditional Chinese medicine groups of high, medium, low dose, with 10 rats in each group. The other 10 rats were fed with ordinary diet as normal group. Rats in traditional Chinese medi?cine of high, medium, low groups were given Zexie Decoction suspension of 16.2, 10.8 and 5.4 g/(kg·d) respectively;Rats in modern medicine group was given Valsartan hydrochlorothiazide 16.65 mg/(kg·d);the model group and normal group was ad?ministered with equal volume of distilled water. Animals were feed with medications at 1 mL/100 g by gavage for 4 weeks. On the 1st , 4th , 7th , 14th and, 28th day of administration, we measured SBP and collected 24 h urine. We employed immunohis?tochemistry to detect renal AQP-2 protein expression level and RT-PCR to detect renal AQP-2 mRNA transcription level. Results The rank of SBP from high to low is:model group>traditional Chinese medicine medium and low dose groups>traditional Chinese medicine high dose group and western medicine group>normal group. The rank of urine volume from high to low is:Western medicine group and traditional Chinese medicine high dose group>traditional Chinese medicine me?dium and low dose group > normal group, the difference was not statistically significant between traditional Chinese medi?cine medium and low dose group , or between western medicine group and traditional Chinese medicine high dose group. The renal AQP-2 in epithelial cells along the collecting duct wall of rats in model group show brown particles which are darker and wider distributed than those in normal group and traditional Chinese medicine of high, medium, low dose groups. RT-PCR results show that AQP-2 mRNA expression is highest in rats of model group and lowest in rats of traditional Chi?nese medicine high dose group (P<0.05). No statistical significance of AQP mRNA level was found between traditional Chi?nese medicine low group and model group (P < 0.05). Conclusion Modified Zexie Decoction can lower blood pres?sure by inhibiting the expression of AQP-2.
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0. 05), the mean effective discharge time was 3. 4+ 3. 2 (P0. 05), the mean effective discharge time was 2. 6+1. 7 (P