Objective To evaluate the effect of curcumin on spinal inflammatory factor in rats with diabetic neuropathy. Methods Diabetic neuropathy was induced by intraperitoneal injection with 1% STZ (60 mg/kg) in sprague-dawley rats. These diabetic rats were randomly allocated to diabetic group (D group, n=10) and curcumin group ( C group , n = 10 ) . Another 10 age-matched normal rats served as controlled group ( N group , n = 10 ) . 28 days after STZ injection, the rats in C group received daily intragastric administration of curcumin (200 mg/kg) whereas those in D group received the same volume of normal saline for 2 weeks. Caudal vein blood glucose levels at T1( before STZ injection)and at T2-T8(2、7、14、21、28、35、42 days after STZ injection)from all rats were detected. Responses to the mechanical stimulus were measured with von Frey filament, and paw withdraw threshold (PWT) was recorded at T1 and at T3 to T8. At T8,the rats were killed and lumbar segments of spinal cord were removed to detect TNF-αand IL-6 content. Results Compared to N group, rats in both C and D group showed hyperglycemia at T2 to T8 (P<0.05) and lower PWT at T4~ 8 (P < 0.01). Compared to D group, C group showed higher PWT at T7,8(P<0.05). Both D and C group showed higher levels of blood sugar at T2 ~ 8 than that at T1 (P < 0.05). C group showed higher PWT at T7,8 than that at T6(P<0.05). Compared to N group,spinal TNF-αand IL-6 content increased in both D and C groups (P<0.05). Compared to D group, C group had reduction of TNF-αand IL-6 concentration (P < 0.05). Conclusion Curcumin can attenuate diabetic neuropathic pain on rats probably by reducing inflammatory factor in spinal cord.

Objective To understand the trend of drinking-tea type fluorosis in the diseased areas in Inner Mongolia Autonomous Region,and to evaluate the effect of prevention and control measures.Methods In 2009 and 2012,6 monitored counties were selected in Inner Mongolia Autonomous Region; 5 diseased villages were selected in each monitored county,and 10 families were selected in each monitored village; fluorine content of brick tea was tested,and dental fluorosis conditions of all 8 to 12-year-old students and skeletal fluorosis conditions of all 36 to 45-year-old adults were examined.In 2012,in each monitored village,1 water sample of the drinking water source was collected respectively from five positions(east,south,west,north and the central of the village),and fluoride content of drinking water wastested.Results In 2009,the mean of brick tea fluorine content was 541.48 mg/kg in the monitored villages,and the fluoride content ≤ 300 mg/kg accounted for 17.62％.(49/278).In 2012,the mean of brick tea fluorine content was 536.06 mg/kg,and the fluoride content ≤300 mg/kg accounted for 11.00％(33/300).Total exceeding standard rate of the water fluoride content was 40.00％(12/30).In 2009,the detection rate of the children's dental fluorosis was 52.39％ (274/523),very mild,mild,moderate and severe cases accounted for 9.56％(50/523),19.86％(104/523),21.03％(110/523) and 1.91％(10/523),respectively.In 2012,the detection rate of the children's dental fluorosis was 35.71％(200/560),very mild,mild,moderate and severe cases accounted for 14.11％ (79/560),11.43％ (64/560),9.64％ (54/560),and 0.54％ (3/560),respectively.Compared with 2009,the proportion of moderate and severe cases reduced in 2012(W =40 696.0,P ＜ 0.01).In 2009,the detection rate of adult skeletal fluorosis was 23.52％ (167/710),mild,moderate and severe cases accounted for 17.32％(123/710),4.51％(32/710) and 1.69％(12/710),respectively.In 2012,the detection rate of adult skeletal fluorosis was 20.12％ (103/512),mild,moderate and severe cases accounted for 17.38％ (89/512),2.54％ (13/512) and 0.20％ (1/512),respectively.Compared with 2009,the proportion of moderate and severe cases reduced in 2012(W =12 797.5,P ＜ 0.01).Conclusion The drinking-tea type fluorosis in Inner Mongolia Autonomous Region has been controlled to some degree,but still serious in some areas;prevention and control measures need to be further strengthened.

Objective To evaluate the effect of curcumin preconditioning on the activation of mast cells during intestinal ischemia/reperfusion (I/R) in rats.Methods Twenty-four female Sprague-Dawley rats,weighing 180-220 g,were randomly divided into 3 groups (n =8 each) using a random number table:sham operation group (S group),intestinal I/R group (I/R group),and curcumin preconditioning group (Cur group).Intestinal I/R was produced by occlusion of superior mesenteric artery (SMA) for 75 min followed by reperfusion.At 5 days before I/ R,curcumin 200 mg/kg (in 20 mg/ml normal saline) was given through a gastric tube in Cur group,while the equal volume of normal saline was given instead in S and I/R groups.All the rats were sacrificed at 4 h of reperfusion,and the intestinal specimens were obtained for microscopic examination and for determination of tryptase expression and β-hexosaminidase content.Intestinal damage was assessed and scored according to Chiu.Results Compared with S group,Chiu's score and β-hexosaminidase content were significantly increased,and the expression of tryptase was up-regulated in I/R and Cur groups.Compared with I/R group,Chiu' s score and β-hexosaminidase content were significantly decreased,and the expression of tryptase was down-regulated in Cur group.Conclusion The mechanism by which curcumin preconditioning attenuates intestinal I/R injury is related to inhibited activation of mast cells of rats.

Objective To evaluate the role of mTOR in spinal cord in the development of diabetic neuropathic pain in rats.Methods Sixty adult male Sprague-Dawley rats,aged 2 months,weighing 180-220 g,were used in the study.Forty-five rats among them were chosen randomly and diabetes mellitus was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg and confirmed by blood glucose ＞ 16.7 mmol/L on day 3 after STZ injection.The left 15 rats received intraperitoneal injection of the equal volume of citric acid-sodium citrate buffer and served as normal control group (group C).Paw withdrawal threshold to von Frey filament stimulation was measured in the right hind paw before STZ injection and on 3,6,9,12,15,18,and 21 days after STZ injection.The diabetic rats with mechanical pain threshold decreasing by more than 50％ of the baseline were allocated to diabetic neuropathic pain group (group DP),and by less than 25 ％ of the baseline were allocated to diabetic non-neuropathic pain group (group NP).The rats were sacrificed at 21 days after STZ injection,and their lumbar enlargements of the spinal cord were removed for determination of the expression of mTOR and phosphorylated mTOR (p-mTOR) by Western blot.Results The expression of mTOR was significantly up-regulated in DP and NP groups when compared with group C (P ＜ 0.05),the expression of p-mTOR was up-regulated in DP group,and no significant change was found in the expression of p-mTOR in group NP (P ＞ 0.05).Compared with group NP,the expression of p-mTOR was significantly up-regulated (P ＜ 0.05),and no significant change was found in the expression of mTOR in group DP (P ＞ 0.05).Conclusion Activation of mTOR in the spinal cord is involved in the development of diabetic neuropathic pain in rats.

Objective To evaluate the effect of intrathecal rapamycin on diabetic neuropathic pain in rats.Methods Thirty adult male Sprague-Dawley rats,weighing 180-220 g,in which IT catheters were successfully implanted,were randomly divided into 5 groups (n =6 each) using a random number table:control group (group C),diabetic neuropathic pain group (group DN),rapamycin 1 μg group (group R1),rapamycin 3 μg group (group R3) and rapamycin 10 μg (group R10).Diabetes mellitus was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg on 5 days after IT catheters were implanted in DN,R1,R3 and R10 groups.Citric acid-sodium citrate buffer 6 ml/kg was injected intraperitoneally in group C.In R1,R3 and R10 groups,rapamycin (dissolved in 10 μl 4％ dimethyl sulfoxide) 1,3 and 10 μg were intrathecally injected,respectively,once a day for 7 consecutive days starting from day 21 after STZ injection,while the equal volume of 4％ dimethyl sulfoxide was given instead in C and DN groups.Paw withdrawal threshold (PWT) to yon Frey filament stimulation was measured before IT catheters were implanted,before STZ injection,on 7,14 and 21 days after STZ injection,and on 1,3,5 and 7 days after rapamycin administration.After measurement of PWT,the rats were sacrificed and L2-5 segments of the spinal cord were removed for determination of the expression of mTOR and phosphorylated mTOR (p-mTOR),S6K and phosphorylated S6K (p-S6K) (by Western blot) and expression of mTOR mRNA and S6K mRNA (by RT-PCR).Results Compared with group C,MWT was significantly decreased at 14 and 21 days after STZ injection in DN,R1,R3 and R10 groups,and the expression of mTOR,p-mTOR,S6K,p-S6K,mTOR mRNA and S6K mRNA was up-regulated in group DN (P ＜ 0.01).Compared with group DN,MWT was significantly increased at 5 and 7 days after rapamycin administration in group R1,at 3,5 and 7 days after rapamycin administration in group R3,and at 1,3,5 and 7 days after rapamycin administration in group R10,and the expression of mTOR,p-mTOR,S6K,p-S6K,mTOR mRNA and S6K mRNA was down-regulated in R1,R3 and R10 groups (P ＜ 0.01).Conclusion Intrathecal rapamycin can alleviate diabetic neuropathic pain in rats.

Objective To evaluate the effects of curcumin preconditioning on the activity of xanthine oxidase (XOD) during intestinal ischemia-reperfusion (I/R) in rats.Methods Thirty female Sprague-Dawley rats,aged 180-220 g,were randomly divided into 3 groups (n =10 each) using a random number table:sham operation group (S group),intestinal I/R group (I/R group),and curcumin preconditioning group (Cur group).Intestinal I/R was induced by clamping the superior mesenteric artery for 75 min followed by reperfusion.Curcumin 200 mg/kg was given everyday for 5 days before intestinal I/R in Cur group and the equal volume of normal saline was given instead of curcumin in S and I/R groups.The rats were sacrificed at 4 h of reperfusion and the intestinal specimens were obtained for microscopic examination of pathologic changes which were graded using Chiu scoring system and for determination of XOD activity,content of malondialdehyde (MDA),and superoxide dismutase (SOD) activity.Results Compared with S group,the Chiu score,activity of XOD and content of MDA were significantly increased,while the activity of SOD was decreased in I/R and Cur groups (P ＜ 0.05).Compared with I/R group,the Chiu score,activity of XOD and content of MDA were significantly decreased,and the activity of SOD was increased in Cur group (P ＜ 0.05).Conclusion Curcumin preconditioning can attenuate intestinal I/R injury in rats,which may be due to inhibition of XOD activity and decreased oxidative stress in intestinal tissues.

Objective To evaluate the role of nitric oxide (NO) in the spinal cord in the maintenance of diabetic neuropathic pain in rats.Methods Male Sprague-Dawley rats,aged 2 months,weighing 180-200 g,were used in the study.Diabetes mellitus was induced by intraperitoneal streptozotocin (STZ) 60 mg/kg and confirmed by blood glucose ＞ 16.7 mmol/L on day 2 after STZ injection.Twenty diabetic rats were randomly allocated into diabetes mellitus group (DM group,n =10) and L-NAME (non-selective NOS inhibitor) group (LN group,n =10).Another 10 age-matched normal rats served as control group (C group).On 21 days after STZ injection,L-NAME 10 mg/kg was injected intraperitoneally once a day for 7 consecutive days in LN group,whereas the equal volume of normal saline 5 ml/kg was given instead of L-NAME in DM group.Paw withdrawal threshold to yon Frey filament stimulation (PWT) was measured before STZ infection and on 7,14,21 and28 days after STZ injection.The rats were sacrificed after the last measurement of PWT and the lumbar segments of spinal cord were removed for determination of NO content and neuronal nitric oxide synthase (nNOS) expression (by Western blot analysis) in spinal cord tissues.Results Compared with C group,PWT was significantly decreased on 14,21 and 28 days after STZ injection,and the NO content and nNOS expression in spinal cord tissues were increased in DM and LN groups (P ＜ 0.05).Compared with DM group,PWT was significantly increased on 28 days after STZ injection,and the NO content and nNOS expression in spinal cord tissues were decreased in LN group (P ＜ 0.05).Conclusion NO in the spinal cord is involved in the maintenance of diabetic neuropathic pain in rats and the mechanism is related to the enhanced function of nNOS.

Objective To evaluate the effects of curcumin pretreatment on the activity of inducible nitric oxide synthase (iNOS) during lung injury induced by intestinal ischemia-reperfusion (Ⅰ/R) in rats.Methods Twenty-four pathogen-free female Sprague-Dawley rats,weighing 180-220 g,were randomly divided into 3 groups (n =8 each) using a random number table:sham operation group (group Sham);intestinal Ⅰ/R group (group Ⅱ/R);curcumin pretreatment group (group Cur).A rat model of lung injury induced by intestinal Ⅰ/R which was produced by occlusion of superior mesenteric artery for 75 min followed by reperfusion was established.At 5 days before Ⅰ/R,curcumin 200 mg/kg (in 20 mg/ml of normal saline) was given through a gastric tube in group Cur,while the equal volume of normal saline was given instead in Sham and Ⅱ/R groups.The rats were sacrificed at 4 h of reperfusion,and the pulmonary specimens were obtained for determination of wet/dry lung weight ratio (W/D ratio),NO content (by using nitrate reductase method) and iNOS activity (using colorimetric method) and for examination of pathological changes (with light microscope).The pathological changes of the lung were scored.Results Compared with group Sham,the pathological scores,W/D ratio,NO content and iNOS activity were significantly increased in Ⅱ/ R and Cur groups.Compared with Ⅱ/R group,the pathological scores,W/D ratio,NO content and iNOS activity were significantly decreased in group Cur.The pathological changes of lungs were significantly attenuated in group Cur as compared with H/R group.Conclusion The mechanism by which curcumin pretreatment attenuates lung injury induced by intestinal Ⅰ/R is related to decrease in iNOS activity in rats.

Objective:To understand the change trend of people's condition in tea drinking endemic fluorosis area of Inner Mongolia Autonomous Region, and to provide scientific basis for formulating prevention and control strategies.Methods:From 2009 to 2018, a cross-sectional survey was conducted in 30 villages of 6 banners (counties) of drinking tea type of endemic fluorosis of Inner Mongolia Autonomous Region. The tea drinking habits of residents were investigated. Ten families were selected from each monitoring village to collect brick tea samples, and the fluorine content in brick tea was detected for health risk assessment. In each monitoring village, one water sample was collected from each drinking water source. Fluoride ion selective electrode method was used to detect fluorine in tea and water. The prevalence of dental fluorosis in children aged 8-12 years old was examined and the X-ray examination and analysis were carried out for all the permanent residents aged 36-45 years and living in the local area for more than 5 years.Results:From 2009 to 2018, a total of 3 000 brick tea samples were collected. The geometric mean value of tea fluorine was 522.01 mg/kg, and the annual per capita consumption of brick tea by permanent residents was 2.52 kg. The average daily intake of fluorine in brick tea was 4.11 mg. According to the standard of "Total Fluoride Intake of Population" (WS/T 87-2016), there were 6 years of risk quotient > 1 in 10 years, while according to the World Health Organization (WHO) recommend standard, there were 5 years of risk quotient > 1. From 2012 to 2018, 210 water samples were detected, and the geometric mean value of fluorine in water was 0.90 mg/L, and the qualified rate was 84.76% (178/210). A total of 5 384 children aged 8-12 years old were examined and 1 562 dental fluorosis patients were detected. The total detection rate of dental fluorosis in children was 29.01% (1 562/5 384), and the dental fluorosis index was 0.62 (very mild). A total of 1 890 adults aged 36 to 45 years old were examined by X-ray. The detection rate of skeletal fluorosis was 18.10% (342/1 890). There were 77 patients with moderate and severe skeletal fluorosis.Conclusions:The brick tea fluorine content of residents in Inner Mongolia Autonomous Region is high, and there are health risks. The dental fluorosis of children aged 8-12 years old is very mild, and there are still moderate and severe skeletal fluorosis patients in adults. Therefore, it is necessary to strengthen the supervision of brick tea market and strengthen health education for residents.

Objective To evaluate the effect of resveratrol on the activity of NADPH oxidase during acute lung injury induced by intestinal ischemia-reperfusion (I/R) in rats.Methods Thirty-two pathogenfree healthy female Sprague-Dawley rats,weighing 180-230 g,were divided into 4 groups (n =8 each) using a random number table:sham operation group (Sham group),intestinal I/R group (I/R group),vehicle group (Veh group) and resveratrol group (Res group).Intestinal I/R was produced by occlusion of the superior mesenteric artery for 75 min followed by 4 h of reperfusion.In group Res,resveratrol 15 mg/kg was intraperitoneally injected for 5 consecutive days before establishment of the model and at 15 min before ischemia.The equal volume of vehicle (0.5％ alcohol) was intraperitoneally injected in group Veh.The equal volume of normal saline was intraperitoneally injected in Sham and I/R groups.At the end of reperfusion,the rats were sacrificed and the lung was removed for microscopic examination of pathologic changes which were scored and for determination of wet/dry weight ratio (W/D ratio),malondialdehyde (MDA) content and superoxide dismutase (SOD) activity (by colorimetric method) and expression of NADPH oxidase subunits (gp91phox and p47phox) in lung tissues (by Western blot).Results Compared with group Sham,pathologic scores,W/D ratio and MDA content were significantly increased,the expression of gp91phox and p47phox was up-regulated,and the activity of SOD was decreased in I/R and Veh groups (P＜0.05).Compared with I/R and Veh groups,pathologic scores,W/D ratio and MDA content were significantly decreased,the expression of gp91phox and p47phox was down-regulated,and the activity of SOD was increased in group Res (P＜0.05).Conclusion The mechanism by which resveratrol reduces intestinal I/R-induced acute lung injury is related to inhibiting NADPH oxidase-mediated oxidative stress response of rats.