Objective To observe glucose metabolism in C57 mice treated with different doses of fluoride.Methods Forty male C57 mice (body weight 20-24 g) were divided into four groups which were exposed to 0,50,100 and 150 mg/L sodium fluoride (NaF) by random number table according to body weight,each group had 10 mice.At 2,4,6,8,10 and 12 weeks after fluoride exposure,body weight was measured,blood glucose and glycosylated hemoglobin were detected by blood glucose meter and glycosylated hemoglobin meter,serum insulin and glucagon were detected by enzyme-linked immunosorbent assay (ELISA).Results At 10 and 12 weeks after fluoride exposure,the differences of fasting glucose between groups of C57 mice were statistically significant (F =35.12,21.92,all P ＜ 0.05),the fasting glucose of 100,150 mg/L fluoride groups [(7.7 ± 0.2),(7.3 ± 0.3),(8.6 ± 0.5),(9.1 ± 0.7)mmol/L] were higher than those of the control group [(5.4 ± 0.3),(5.0 ± 0.3)mmol/L,all P ＜ 0.01].The differences of glycosylated hemoglobin,glucagons between groups were statistically significant (F =3.85,8.74,all P ＜ 0.05).The glycosylated hemoglobin of 100,150 mg/L fluoride groups [(7.73 ± 0.76),(7.80 ± 1.15) mmo]/L] were higher than those of the control group [(5.43 ± 1.27) mmol/L,all P ＜ 0.05]; serum glucagon levels of 50,100,150 mg/L fluoride groups [(19.15 ± 11.84),(26.55 ± 15.97),(20.05 ± 7.29)ng/L] were lower than that of the control group [(48.35 ± 2.79)ng/L,all P ＜ 0.01].Conclusion Long term excess fluoride intake can reduce the function of sugar metabolism in C57 mice.

Objective To observe gene different expression of unfolded protein response signaling pathway in human osteoblasts under the excessive fluoride ,and explore the role of endoplasmic reticulum stress in fluorosis .Methods Human osteoblasts were cultured with fluoride ,intervening for 24 h .Cell viability and apoptosis were inspected by MTS assay and flow cytometer respective‐ly .The UPR signaling pathway was examined by real time PCR array ,and protein expressions were detected by Western blot .Re‐sults T he cell survival rates w ere (100 .678 5 ± 2 .830 3 )% ,(105 .393 4 ± 2 .538 4 )% ,(106 .125 7 ± 2 .048 3 )% ,(77 .977 3 ± 2 .544 3)% (P<0 .05) ,(30 .237 7 ± 0 .632 73)% (P<0 .05) treated with sodium fluoride at the concentration 0 ,5 ,10 ,20 ,40 ,80 mg/L respectively .Apoptosis rate inspected by flow cytometer was 4 .8% in 5 mg/L group ,13 .8% in 10 mg/L group ,37 .0% in 20 mg/L group ,58 .9% in 40 mg/L group ,63 .2% in 80 mg/L group (P<0 .05) .Only 1 gene was down regulated and 14 genes were up regulated .Western blot analysis showed BIP ,ATF4 ,CHOP and IRE1 both showed their protein expression gradually up regula‐ted with fluorine dose .XBP1 expression gradually increased in NaF 5-20 mg/L ,and its expression decreased at 40 and 80 mg/L . Conclusion Sodium fluoride can cause osteoblasts endoplasmic reticulum stress pathway through PTEN and IRE1 pathway ,and at high concentrations can cause apoptosis of osteoblast .

Computational epidemiology is a fast-developing and interdisciplinary research area .Through comprehensive computation-analysis of multi-uncertain factors affecting the epidemic process , this method may add to our knowledge about epidemic patterns and help design reasonable response plans and emergency strategies .This article briefly summarizes the idea and theory of computational epidemiology based on related researches in the recent years , introduces the application of this method in case of smallpox bioterrorism and influenza pandemic , and predicts the development of this area .

Objective To explore excessive fluoride on expression of osteocalcin (OC) in osteoblast and glucolipid metabolism in mice.Methods 3T3-L1 preadipocyte and MC3T3-E1 osteoblast were conventionally cultured,MC3T3-E1 cells were stimulated with O,2,10 and 50 mg/L sodium fluoride (NaF) to establish fluorine cell model,and levels of OC were tested.The corresponding NaF concentration resulted in the highest OC level was used as the optimal fluorine concentration.Cell experiments were divided into four groups:3T3-L1,3T3-L1 + NaF,3T3-L1 + MC3T3-E1 and 3T3-L1 + MC3T3-E1 + NaF.The treatment groups were respectively or jointly treated with the optimal concentration of NaF (50 mg/L) or MC3T3-E1 osteoblast,enzyme linked immunosorbent assay (ELISA) was used to detect OC and adiponectin (APN) levels.At the same time,40 C57BIL/6 mice were numbered by weight,randomly divided into control and fluoride groups,20 per group,control group drunk pure water,fluoride group drunk 100 mg/L NaF solution,changes of teeth and body weight [M (P25,P75)] of the mice were observed.Serum OC and APN levels were tested by ELISA at 12 weeks after modeling.The fasting plasma glucose (FPG) and the fasting plasma insulin (FINS) were detected by glucose oxidase and chemiluminescence methods,and insulin resistance (HOMA-IR) was evaluated.Results The APN levels of 3T3-L1,3T3-L1 + NaF,3T3-L1 + MC3T3-E1 and 3T3-L1 + MC3T3-E1 + NaF groups were (0.94 ± 0.18),(1.07 ± 0.21),(1.76 ± 0.20),and (2.49 ± 0.43) μg/L,MC3T3-E1 osteoblast with NaF had promote collaborative interaction effect on APN levels (F =14.519,P ＜ 0.01).The body weight of mice in fluoride group [27.5 (25.8,28.3) g] was significantly lower than that of the control group [31.4 (30.3,32.6) g,Z =-4.695,P ＜ 0.01].The levels of FPG [(7.78 ± 1.86) mmol/L],FINS [(3.22 ± 0.75) mU/L],OC [(6.11 ± 1.49) μμg/L],APN [(8.65 ± 1.78) μg/L] and HOMA-IR (1.15 ± 0.49) were higher than those of control groups [(5.40 ± 1.51) mmol/L,(2.45 ± 0.64) mU/L,(3.14 ± 0.92) μg/L,(4.03 ± 1.45) μg/L,0.62 ± 0.31],the differences were statistically significant (t =-4.466,-3.518,-7.560,-9.002,-4.182,P ＜ 0.01).OC levels in mice were positively correlated with FPG,FINS,APN and H-OMA-IR (r =0.868,0.707,0.911,0.818,P ＜ 0.01).Conclusion The OC of osteoblast in mice exposed to fluoride is increased significantly,OC levels in mice are closely related to blood glucose and APN,it is one of the key molecules in lipid metabolism.

Objective:To investigate the effect of enhancing the strength of the hamstring on the stability of the knee joint.Methods:Thirty patients with anterior cruciate ligament (ACL) tears were randomly divided into a training group ( n=15) and a control group ( n=15). After the injury′s edema stage, all of the subjects received the standard 6-stage rehabilitation training for ACL injury, including isokinetic exercise, isometric tension and contraction exercise, single or bipedal jumping, proprioception exercises and cardiovascular exercise. On the basis of that standard training, additional hamstring strengthening training was given to the training group. It involved three sessions of weight-bearing flexion of the knee joint six to eight times, at least five times a week for three months. All of the subjects underwent the passive relaxation test (PRT), knee function scoring (Lysholm scores) and weight-bearing MRI before and within 1 month after the training. Anterior shift of the tibia (TAS) was measured using weight-bearing magnetic resonance imaging (MRI). Results:Before the training there were no significant differences between the groups in terms of average PRT or Lysholm scores. After the training, the average PRT score in neither group had improved significantly. The average Lysholm scores of the training and control groups were not significantly different either, though both groups′ averages had improved significantly compared with before the training. The average tibial shifts were also significantly smaller than before the training, with the training group′s average significantly smaller than that of the control group.Conclusion:Increasing hamstring muscle strength can reduce tibial anteversion in the weight-bearing upright position and improve the stability of the knee joint after ACL injury.