Objective To investigate the protective effects of astragalus preconditioning on the tolerance of ischemia time of mouse small intestine . Methods C57BL/6 mice were randomly divided into 5 groups (n = 7): sham operation group (Sham group),intestinal ischemia reperfusion group (IR group) and astragalus preconditioning group (ASIR group). IR group and ASIR group include 2 sub-groups respectively, specifically, 2 h reperfusion was performed 45 min (ASIR1) and 60 min (ASIR1) after blocking superior mesenteric artery. Intestinal terminal morphology was observed by light microscope after HE coloration . Serum levels of LPS , DAO and intestinal mucosa TNF-α were measured by ELISA. Intestinal Cyto C expression were detected by immunofluorescence. Results Astragalus preconditioning reduces Chiu′s score significantly. Expression of Cyto C was significantly down-regulated in astragalus preconditioning groups, and levels of LPS, DAO and TNF-αsignificantly decreased. The damages in IR2 group is obviously severe than in IR1, but there were no significant differences between this two groups after pretreatment with astragalus. Conclusion Astragalus preconditioning has obvious protective effects to intestinal ischemia reperfusion, and enhances the tolerance to longer time of ischemia.

Objective:To investigate the stress distribution surrounding an implant under different thickness of cancellous bone and cortical bone,and to analyze the influence of thickness ratio and total thickness of bone tissues on the reliability of an implant.Methods:By using the commercial finite element method software Abaqus, a simplified three-dimensional model of a jawbone consisting of a cancellous bone,a cortical bone,an implant,and a ceramic crown was constructed,and then the computation was performed.Under the condition that the system was loaded by lateral and normal stresses, the influence of thickness ratio and total thickness of cancellous bone and cortical bone in the stress distribution surrounding the implant was studied,where the thickness ratios were 3∶1, 2∶1, 1∶1, 1∶2, and 1∶3;the total thickness were 0.5, 1.0, 2.0, 3.0 and 4.0 mm, respectively. Results:The maximum stresses on the cortical bone,the cancellous bone as well as the implant were all found to decrease with the increasing of the total thickness of cortical and cancellous bones,with a higher decreasing rate in the range between 0.5-2.0 mm and a lower decreasing rate between 2.0-4.0 mm. More importantly, the maximum value of stress in the cortical bone within the neck region of the implant was observed to increase dramatically via reducing the total thickness below 2 mm, while it was increased insignificantly when the total thickness was above 2.0 mm. Conclusion:The thickness ratio and the total thickness of cancellous bone and cortical bone have strong influence in the stress distribution surrounding the implant.In dental implantation surgery, the total thickness of cancellous bone and cortical bone should be at least 2 mm, and therefore 2 mm is an optimal value.

Adult ; Aneurysm, Dissecting ; complications ; Aortic Aneurysm ; complications ; Humans ; Lower Extremity ; physiopathology ; Male

BACKGROUND: Embryonic pancreatic tissue is characterized by its abundance, potent in proliferation & differentiation, and minimal immunological rejection. It is widely considered as potential pancreatic endocrinological stem cells resource for treating diabetes mellitus.OBJECTIVE: To investigate the embryonic mouse pancreatic tissue isolation technique and observe the recipients' blood glucose regulatory effects of the grafted embryonic pancreas in an experimental diabetes mellitus mouse model.METHODS: Pancreatic tissue from C57B1/6 mouse embryos at embryonic days 11.5-16.5 was isolated under the stereomicroscope. C57BL/6 mouse models of streptozocin-induced diabetes mellitus were established and then randomly divided into two groups: transplantation group, in which, five pieces of pancreatic tissue of mice at embryonic 16.5 days were transplanted into mouse renal capsule, and sham-operated control group, in which, 0.05 mL RPMI1640 culture medium was injected into mouse renal capsule. When blood glucose level of the transplantation group mouse was≤ 11.2 mmol/L, the endocrine function of embryonic pancreatic tissue transplanted was detected by IPGTT and IPITT methods and then the transplanted graft was removed for observing the blood glucose relapse.RESULTS AND CONCLUSION: Nearly intact pancreatic tissue of mice at embryonic days 11.5-16.5 could be isolated through the use of stereomicroscope. Pancreatic tissue morphology and color of mice ≤ embryonic 12.5 days were difficultly distinguished from adjacent tissue and they could only be isolated carefully according to the relationship with adjacent organs. Pancreatic tissue of mice > embryonic 12.5 days exhibited initial endocrinological tissue morphology mimic white cauliflower. Histological and ELISA examinations showed that embryonic pancreatic tissue could express and secrete insulin and the insulin level was gradually increased with developmental time. Embryonic pancreatic tissue could grow beneath the recipient renal capsule. The insulin and glucagon expression in the post-transplantational pancreatic tissue graft was increased compared with prior to transplantation. These results suggest that pancreatic tissue is a potential stem cell resource for treating the diabetes mellitus.

Animals ; Cardiovascular Diseases ; etiology ; Cerebrovascular Disorders ; etiology ; Homocysteine ; metabolism ; Humans ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Polymorphism, Genetic

OBJECTIVETo understand the prevalence and risk factors for suicidal ideation among college students and to provide a scientific basis for promoting psychological health and suicide prevention.

METHODS623 college students at Central South University were selected using stratified cluster sampling and administered a suicide ideation questionnaire, a Symptom Check List (SCL-90), an Adolescent Self-Rating Life Events Check List (ASLEC), a Social Support Rating Scale (SSRS) and a questionnaire about background information. Multivariate logistic regression analysis was employed to identify risk factors for suicide ideation.

RESULTSOne year prior to our investigation, 14.6% of respondents had suicide ideation, 2.5% had made a specific suicide plan, and 1.8% had made a suicide attempt. The main risk factors for suicide ideation were dissatisfaction with the selected major of study, limited social support, recent negative life events and depressive tendency.

CONCLUSIONSThe prevalence of suicide ideation among these college students was high. Appropriate measures focusing on the risk factors identified in this study should be urgently developed to prevent suicides in college students.

China ; Female ; Humans ; Logistic Models ; Male ; Risk Factors ; Students ; psychology ; Suicide, Attempted ; psychology ; statistics & numerical data ; Surveys and Questionnaires ; Universities

Objective To construct eukaryotic expression vector encoding rat IMD gene and deliver it into rat renal tissue via ultrasound-mircobubbles. Methods IMD gene was inserted into pCDNA3.1 ( + )between Hind Ⅲ and EcoRI enzyme sites. The recombinant plasmid designated as IMD-pCDNA 3.1 wasconfirmed by restrictive enzyme digestion and sequencing. Eighteen male Wistar rats were randomized into 3groups, which were treated with no transfection, empty vector transfection and IMD transfection, respectively, in renal tissue via ultrasound-microbubbles. RT-PCR and Western blotting were applied to detect the expression level of IMD. Results Enzyme- digestion and sequencing data showed that IMD-pCDNA 3.1 was correctly constructed. The differences in ALT, AST, BUN and SCr were not significant; No obvious damage in the glomerular, tubular and interstitial was observed in all the treated groups;Compared with non-transfection group and empty vector-transfection group, IMD mRNA and protein expression in IMD transgenic renal tissue were significantly increased. Conclusion IMD-pCDNA 3.1 expression vector was successfully constructed and well expressed in rat kidney.

Objective To investigate the effect of intermedin (IMD) on renal ischemia/ reperfusion (I/R) injury after the up-regulation of IMD. Methods A total of 24 healthy Wistar male rats were randomly divided into four groups,sham-operated group,I/R group,IMD gene transfection +I/R group and empty plamid +I/R group.All the animals were killed at the end of 24 h of reperfusion.Histological changes and renal function were estimated.The expression and site of IMD were determined by Immunohistochemistry method,semi-quantitative RT-PCR and Western blotting.The protein expressions of endothelin 1 (ET-1),tumor necrosis factor αt (TNF-α) were detected by Western blotting. Results Compared with sham-operated group,tubulointerstitial pathological injury was significant aggravated in I/R group (7.6±2.3) and empty plamid +I/R group (7.0±1.8),and such injury was improved in IMD+I/R group (1.5±0.8) (P＜0.05).Compared with I/R group and empty plamid +I/R group,the renal dysfunction of IMD +I/R group was obviously lessened [BUN:(7.73±1.03) mmol/L vs (10.13±2.14) mmol/L,(9.77±1.92) mmol/L; Scr:(58.50±3.27) μmol/L vs (80.33±7.15) μmol/L, (75.67±7.58) μmol/L,all P＜0.05].IMD expression was weak in the plasma of tubulointerstitial cells in sham-operated group,and was up-regulated in I/R group. Compared with I/R group, immunohistochemical IMD expression increased obviously (262.03±67.89 vs 175.57±48.06,P＜0.01).The mRNA expression of IMD in IMD+I/R group was up-regulated significantly by 60.7％,66.1％ and the protein expression of IMD in IMD+I/R group increased significantly by 51.4％,55.9％ as compared to I/R and empty plasmid +I/R group.Meanwhile,the protein expressions of ET-1 and TNF-αt in IMD+I/R group were obviously lower compared with those in I/R group (ET-1:0.08±0.02 vs 0.17±0.02; TNF-α:0.21±0.04 vs 0.35± 0.02,all P＜0.05). Conclusion IMD gene transfected into kidneys of rats prior to I/R surgery can attenuate the over-expressions of both ET-1 and TNF-o in I/R injured rat kidneys as well as the damages to the structure and function of the kidneys.

A strain of cellulolytic bacterium was isolated from soil by cellulostic plate. The morphological and physiological properties of this strain were studied. According to Bergey's Manual of Determinative Bacteriology ,the strain was identified as a new strain of the Sporocytophaga.

Objective To explore the effect of excessive fluoride on expression of mRNA and protein of Wnt3a and β-catenin in rats' osteoblasts and its correlation with pathogenic mechanism of fluorosis.Methods Thirty-six healthy SD rats,weighting 100-120 g and according to body mass,were randomly divided into three groups(twelve in each group).The rats of control were fed wich tap water(fluoride ＜ 1 mg/L) and the experimental rats were exposed to NaF(low-fluoride group:5 mg/L,high-fluoride group:50 mg/L) added to the drinking water to establish the chronic fluorosis model.After fed for eight morth,all rats were killed and metaphysic of femoral was collected.Rat dental fluorosis was observed and bone fluorine was detected by ashing-fluorin ion selective electrode method.The content of bone alkaline phosphatase (BALP) and tartrate-resistant acid phosphatase 5b(TRACP 5b) in rats' serum was detected by enzyme-linked immunosorbent assay (ELISA).The morphologic changes of the bone were observed by microscopy.The expression of mRNA and protein of Wnt3a and β-catenin in osteoblasts of rats was analyzed with gray scale by hybridization in situ and immunohistochemistry methods,respectively.Results Detection rate of dental fluorosis,fluoride contents of urine and bone were significantly increased [control group:0.0％,(1.26 + 0.17)mg/L,(305.58 ± 91.26)mg/kg; low-fluoride group:66.7％,(2.06 ± 0.64)mg/L,(632.33 ±123.21)mg/kg; high-fluoride group:91.7％,(7.69 ± 1.96)mg/L,(1088.75 ± 156.16) mg/kg] in the rats treated with fluoride,the difference between groups was statistically significant(χ2 =21.6; F =36.57,467.02; all P ＜0.05).The contents of BALP and TRACP-5b in rats' serum were significantly different between groups(F =89.57,7.68; all P ＜ 0.05).Compared with control group[(16.24 + 1.57)U/L],the contents of BALP in rats' serum of the low-fluoride and high-fluoride groups[(31.47 ± 5.30) and (54.61 ± 2.27)U/L] were increased gradually(all P ＜0.05).Compared with the low-fluoride group,the value in the high-fluoride group decreased significantly (P ＜ 0.05).The contents of TRACP-5b in rats' serum of low-fluoride group[(3.45 ± 1.85)U/L] were elevated significantly(all P ＜ 0.05) compared with the control group[(1.26 ± 0.23)U/L] and the high-fluoride group[(2.74 ± 1.85)U/L].The bone cortices were thickened and the bone trabecula was broadened,arranged closely together in chronic fluorosis rats with significant difference compared with the control group.In the low-fluoride and high-fluoride groups,the expression levels of Wnt3a and β-catenin mRNA (low-fluoride group:132.87 ± 5.72 and 132.57 ± 9.56; highfluoride group:135.60 ± 6.64 and 137.87 ± 9.16) were markedly elevated with significant difference,respectively (F =12.47,5.96; all P ＜ 0.05) compared with those in control groups(119.86 ± 5.04 and 120.58 ± 7.84) by hybridization in situ(P ＜ 0.05),but there was no statistical significance (P ＞ 0.05) of the level of Wnt3a and β-catenin mRNA between low-fluoride and high-fluoride groups.In the low-fluoride and high-fluoride groups,the protein expression of Wnt3a and β-catenin (low-fluoride group:137.50 ± 4.32 and 140.85 + 3.54; high-fluoride group:142.65 ± 11.84 and 152.52 ± 4.64) were markedly elevated with significant difference,respectively (F =10.07,53.82; all P ＜ 0.05) compared with those in control group (124.01 ± 2.63 and 126.75 ± 4.65) by immunohistochemistry(all P＜ 0.05),Wnt3a protein production in the low-fluoride group was increased without statistical significance compared with the high-fluoride group (P ＞ 0.05).But the protein production of β-catenin in the lowfluoride group was elevated with significant difference compared with the high-fluoride group(P ＜ 0.05).The mRNA and protein production of Wnt3a were positively correlated with the mRNA and protein production of β-catenin (r =0.731,0.658; all P ＜ 0.05).Conclusions Rat bone tissue lesions caused by excessive fluoride may be associated with an increased expression of Wnt3a and β-catenin mRNA and protein in osteoblasts.In chronic fluorosis,fluoride stimulates the overexpression of Wnt3a and β-catenin in the Wnt signal transduction pathway,enhances bone osteogenesis and causes skeletal fluorosis.