OBJECTIVE To investigate the apoptosis of hepatocytes in arsenic poisoning rats caused by coal-burning and explore the effects of p53-induced mitochondrial apoptotic pathway on arsenic liver injury.METHODS Wistar rats were fed with 164.74 pp m arsenic conta minated grain at the levels of 15%,30% and 60% (arsenic contents were 25,50 and 100 mg·kg -1 ,respectively)for 90 d. The arsenic contents of urine and hair,apoptosis of hepatocytes and mRNA expression of p53,Bax and Bcl2 in peripheral blood and hepatocytes were evaluated.At the sa me ti me,protein expression of p53, Bax and Bcl2 in hepatocytes were analyzed.RESULTS The arsenic contents of urine and hair increased with the elevation of arsenic dose.The apoptotic rate of hepatocytes in arsenic 50 and 100 mg·kg -1 group were 16.49 ±2.06 and 15.83 ±1 .28,respectively which were significantly higher than the control group and arsenic 25 mg·kg -1 group (9.00 ±0.59 and 9.27 ±0.36,respectively,P <0.05).p53 mRNA expression of peripheral blood in arsenic 100 mg·kg -1 group was 2.69 ±1 .84 while p53 mRNA expression of hepatocytes in arsenic 25,50 and 100 mg·kg -1 group were 1 .63 ±0.28, 1 .91 ±0.38 and 1 .71 ±0.18,respectively which were significantly higher than the control group (0.86 ± 0.15 and 1 .22 ±0.12,respectively,P<0.05).Bax mRNA expression of peripheral blood in arsenic 50 and 100 mg·kg -1 group were 1 .36 ±0.30 and 1 .94 ±0.65 while Bax mRNA expression of hepatocytes in arsenic 100 mg·kg -1 group was 1 .34 ±0.23 which were significantly higher than the control group (0.77 ±0.15 and 0.84 ±0.34,respectively,P<0.05).Bcl2 mRNA expression of hepatocytes in arse-nic 100 mg·kg -1 group was 0.98 ±0.50 which was significantly lower than the control group (2.14 ± 1 .15,P<0.05).p53 protein expression of hepatocytes in arsenic 25,50 and 100 mg·kg -1 group were 1 .06 ±0.56,1 .15 ±0.77 and 0.74 ±0.27,respectively while Bax protein expression of hepatocytes in arsenic 50 and 100 mg·kg -1 group were 0.74 ±0.43 and 0.69 ±0.37 which were significantly higher than the control group (0.36 ±0.1 9 and 0.25 ±0.09,respectively,P<0.05).CONCLUSION Arsenic can induce hepatocytes apoptosis and p53-mediated mitochondrial apoptotic pathway may be involved in the develop ment of rat liver injury in arsenic poisoning rats caused by coal-burning.

Capillary Leak Syndrome ; complications ; Cholestasis, Intrahepatic ; complications ; Humans ; Mucocutaneous Lymph Node Syndrome ; complications

Objective To observe the effect of exenatide on endoplasmic reticulum stress (ERS) in human renal mesangial cells (HRMCs) injured by fluctuating hyperglycemia culture,and to explore the mechanism.Methods HRMCs were randomly divided into three groups:control group (group N,cells were cultured in 5.6 mmol/L glucose for 24 h),fluctuating hyperglycemia group (group F,cells were cultured in 30 mmol/L glucose for 3 h,5.6 mmol/L glucose for 2 h,repeated three times in one day,then 5.6 mmoll/L glucose overnight),fluctuating hyperglycemia and exenatide group (group F+G,HRMCs were cultured in fluctuating hyperglycemia and 100 nmol/L exenatide).MTT assay was used to measure the viability in each group.The apoptosis rates were detected by flow cytometry in three groups.The relative expression of glucose regulated protein78 (GRP78) and CCAAT/enhancerbinding protein homologous protein (CHOP) were tested by Western blot assay.Results Compared with the group N,the cell proliferation level decreased,the cell apoptosis rate increased,and the expression levels of GRP78 and CHOP increased in F group (P ＜ 0.05).After treatment with exenatide,the cell proliferation rate increased,cell apoptosis rate decreased (P ＜ 0.05),and the expression levels of GRP78 and CHOP decreased in F+G group,compared with those of the group F (P ＜ 0.05).Conclusion Exenatide can reduce the damage of fluctuating hyperglycemia on HRMCs by down-regulating the stress levels of the endoplasmic reticulum stress.

OBJECTIVE:To study the bactericidal activity of thymopentin and its derived peptides. METHODS:Agar plate count was adopted to determine the bactericidal activity of thymopentin [arginine(R)-lysine(K)-aspartic acid(D)-valine(V)-tyro-sine(Y),RKDVY],its derived peptide 1 [RKN(agedoite,N)VY] and derived peptide 2(RKKVY)to Gram negative bacterial (Proteusbacillus vulgaris,Escherichia coli) and Gram positive bacterial (Staphylococcus aureus,Enterococcus faecium). There were 15.625-1 000 μg/ml for peptides,102 CFU for bacteria. RESULTS:Three pentapeptides possessed bactericidal activity against Gram negative bacteria. The activities of RKKVY and RKNVY were stronger than RKDVY(P<0.01),there was no significant dif-ference between RKKVY and RKNVY(P>0.05). They also possessed bactericidal activity against Gram positive bacteria,and the activity from strong to weak was RKKVY>RKNVY>RKDVY(P<0.01). CONCLUSIONS:Thymopentin and its derived peptides possess bactericidal activity against Gram negative and positive bacteria,with dose-effect relationship.

Objective To observe the effect of effective monomer of Kangxianling prescription on renal function and extracellular matrix composition of 5/6 nephrectomy rats model, and provide basis for the screening of effective traditional Chinese medicine of anti-renal fibrosis. Methods Sixty SD rats were randomly divided into normal group, model group, chrysophanol group, salvianolate A group, oleanolic acid group and losartan group. The kidney fibrosis model was made by operation. Two months after intervented by correspong drugs, renal pathological changes of all groups were observed, the levels of renal function indexes were detected, and real-time PCR assay was used to detect laminin (LN), fibronectin (FN), type Ⅲ collagen (C-Ⅲ), type Ⅰ collagen (C-Ⅰ) mRNA expression in rat kidney tissue. Results SCr and BUN in model group increased significantly compared with the normal group (P<0.01). SCr and BUN in salvianolate A group decreased significantly compared with the model group (P<0.05, P<0.01). BUN in salvianolate A group decreased significantly compared with the losartan group (P<0.01). The expression of C- ,Ⅲ C-Ⅰand LN were reduced by effective monomer of Kangxianling prescription. Conclusion Effective monomer of Kangqianling prescription can inhibit renal fibrosis through reducing the expression of extracellular matrix components, thereby improve the renal function.

A rapid and sensitive analytical method was developed for the simultaneous determination of fumonisins B1 and B2 in traditional Chinese medicines by HPLC-MS/MS. The detection limits for fumonisins B1 and B2 were 0.25 ng x mL(-1) corresponding to 2 microg x kg(-1) in samples. Recoveries from different samples spiked with fumonisins B1 and B2 at levels ranging from 0.2 to 3 mg x kg(-1) were 84.0%-96.1% and 86.3%-99.3%, respectively. Among the total of 34 samples purchased from local markets, ten samples of which were visibly moldy samples due to inappropriate storage, and 24 were normal samples. The results showed that 6 of the visibly moldy samples and 5 of the normal samples were contaminated with total fumonisins at levels ranging 82.4-2349 microg x kg(-1) and 102-729 microg x kg(-1), respectively.

BACKGROUND:Studies have shown that the number of osteoblasts is often decreased after osteoporosis, and osteoblast replacement therapy becomes a new target for the treatment of osteoporosis. OBJECTIVE:To observe the osteogenic differentiation of human bone marrow mesenchymal stem cels cultured in dexamethasone, vitamin C and beta-glycerophosphate. METHODS:Mesenchymal stem cels were isolated and purified from adult bone marrow using human lymphocyte separation medium. The expression of cel surface markers was detected by flow cytometry. Cel ultrastructure was observed by transmission electron microscope. Then, the bone marrow mesenchymal stem cels were cultured in osteogenic induction medium containing dexamethasone, vitamin C andβ-glycerophosphate, and RT-PCR was used to detect the bone morphogenetic protein-2 mRNA expression after osteogenic induction. RESULTS AND CONCLUSION:A large number of adherent cels were visible as fibrous growth at 2 weeks after culture and strongly expressed CD44, CD29, but did not express CD34, CD45. These cels could be induced to differentiate into osteoblasts, and express bone morphogenetic protein-2 mRNA. Alizarin red staining and alkaline phosphatase staining were positive for the cels. These findings suggest that human bone marrow mesenchymal stem cels cultured in dexamethasone, vitamin C and beta-glycerophosphate can differentiate into osteoblasts, and has a potential for the treatment of osteoporosis.

Objective To develop a three-dimensional element model of pig mandible impact injury and test the simulation results in an attempt to determine the feasibility and reliability of finite element numerical simulation method used in the maxillofacial impact injury.Methods CT data was used to develop a three-dimensional finite element model of pig mandible impact injury,and the dynamic process of impact injury was simulated.The simulation results were compared with the animal experiment and had energy check to validate the reliability and feasibility of the modeling and simulation methods.Results The three-dimensional finite element model was established successfully,containing 61,512 hexahedrons,5,450 tetrahedrons,4,030 trihedrons,and 67,159 nodes.The simulation process was realistic,and the simulation results showed no statistical difference with the animal experiment with regard to strain,acceleration,and other biomechanical properties (P ＞ 0.05).The simulated damage shape had a high similarity with animal specimens,and the result of energy check also complied with energy conservation law.Conclusion Finite element method is effective to simulate the dynamic process of mandible impact which ensures a correct and reliable model and simulation,and thus can be used to analyze the mechanism of maxillofacial impact injury.

Objective Finite element numerical simulation technique was applied to simulate the dynamic projectile injury process of human chin in different injury conditions and the mechanism of injury was discussed by using biomechanical analysis . Methods The 3D finite element model of human mandible projective injury was established to simulate the dynamic projectile inju‐ry process of human chin in different injury conditions (high ,medium and low speeds) ,and the simulation results were used to com‐parative analysis of biomechanics .Results The dynamic damage process of human chin projectile injury was simulated successfully in different injury conditions ,and the more serious injury of mandible was caused by faster speed .Conclusion The finite element method can simulate the projectile injury of mandible effectively ,and can provide a new thought and method for basic research and clinical treatment of oral and maxillofacial war injury .

Objective To simulate a finite element model for biomechanical analysis of mandible chin blast injury and analyze the mechanism of maxillofacial blast injury.Methods The three-dimensional element model of human mandible blast injury was established to simulate the dynamic process of injury to the mandible chin.Von Mises stress and effective strain were evaluated in biomechanical study of the simulation results.Results The dynamic damage process of human mandible chin blast injury was simulated successfully.In the condition of 1 000 mg and 3 cm,the Von Mises stress and effective were maximum at condylar neck region (9.1 × 106 Pa,0.62 × 10-3ε),were second at mandibular angle region (6.1 × 106 Pa,0.42 × 10-3ε),and minimum at mental foramen region (6.1 × 106 Pa,0.39 × 10-3ε).Blast distance rather than blast equivalent produced more effect on the mechanical parameters and damage degree.Conclusions Von Mises stress and effective strain can be applied to the evaluation of bone tissue damage.The finite element method is effective in simulating mandible blast injury and can provide a new thought and approach to clinical treatment of oral and maxillofacial blast injury.