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.

Human parvovirus B19, generally referred to as B19 virus, has been closely associated with a variety of different autoimmune diseases due to the features of its capsid protein. B19 virus VP1 unique region protein that has sites of phospholipase A2 and several antigenic determinants is exposed on the outside of the viral capsid protein. As a result of that, B19 virus VP1 unique region protein can stimulate the host to produce autoantibodies, which induces and/or aggravates the autoimmune diseases. The biological characteristics of B19 virus VP1 unique region protein and its relationships with autoimmune diseases are de-scribed in this review based upon the published literatures and the work achieved by our research team. This review will be helpful to the prevention and treatment of B19 virus infection.

Objectives To explore the clinical features and pathogenesis of Kawasaki disease (KD) combined with sterile pyuria. Methods A total of 420 patients diagnosed of KD were recruited and divided into pyuria group ( 95 patients) and control group ( 325 patients) according to urine routine examination on admission. The clinical data between the two groups were compared. Results There was no difference in gender, age, and the incidence of atypical KD (P all?>?0 . 05 ). The levels of C-reactive protein, D-dimer concentrations, fibrinogen degradation products, alanine aminotransferase, aspartate aminotransferase, and urine retinol binding protein were higher in pyuria group than those in control group (all P>?0 . 05 ). No difference was found in the duration of fever before admission between two groups (P>?0 . 05 ). However, pyuria group had longer duration of fever after treatment with immunoglobulin (P?0.05). Conclusion The morbidity of sterile pyuria in KD patients was 22 . 6%. KD patients with sterile pyuria have more intense inlfammatory response, markedly high coagulation condition, and mild or subclinical renal damage.

Objective The simulation of the human mandible injury was carried out by using the finite element simulation technology ,and the biomechanical analysis of simulation results was developed to explore the mechanism of injuries .Methods The Chinese Visible Human digital data were used to establish the three-dimensional element model of mandible injuries ,and the dynam-ic processes of human mandible injuries in different conditions were simulated ,and the biomechanical analysis were carried out by u-sing the Von Mises stress and effective strain .Results The three-dimensional element model of mandible injuries was established , the dynamic damage and fracture of human mandible were simulated successfully ,the mandibular angle and condylar were the predi-lection parts of high-stress ,high-strain and fractures .Conclusion The Von Mises stress and effective strain can be used to predict and judge the bone tissue injuries ,the finite element method can simulate the impact injuries of mandible effectively ,and the simula-ted results can provide guidance and reference for basic research and clinical treatment of oral and maxillofacial injuries .

Objectives To explore the effect of mibefradil, a kind of novel calcium channel antagonists, on proliferation of human pulmonary artery smooth muscle cells (HPASMCs) induced by platelet-derived growth factor (PDGF). MethodsHPASMCs were culturedin vitro, and randomly divided into control group, PDGF group, Mib group, and PDGF+Mib group. The PDGF group was stimulated by 25 ng/ml of PDGF. Mib group was intervented by 10 μmol/L of Mib. PDGF+Mib group was treated by PDGF and Mib. The reproduction rate in 48 hours and 72 hours were detected by MMT. Cell cycle was detected by lfow cytometry. The expression of proliferating cell nuclear antigen (PCNA) was observed by immunolfuorescence staining (IFS).ResultsThere were statistical differences among four groups in both 48 hours and 72 hours (P all??0.05). There were statistically differences of G0/G1 phase and S phase among four groups (P?

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.

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.