Objective To study the interaction between Cr(Ⅵ)-GSH complex and DNA and to understand the mechanism of DNA conformation change induced by Cr(Ⅵ)-GSH complex. Methods Chromium(Ⅵ) reacts on glutathione forms the chromium (Ⅴ) intermediate complex, and the intermediate complex can induce the conformation change of DNA, in the present paper, ultraviolet and fluorescence spectra, Scatchard equation, fluorescence quenching curve, and fluorescence probe method using ethidium bromide (EB) as a fluorescence probe were employed. Results The chromium (Ⅴ) intermediate complex formed rapidly after the reaction between Cr(Ⅵ) and GSH in Hepes buffer solution at pH=7.4, the complex did not insert into the base pairs on the DNA duplex strand and developed electrostatic binding with the phosphate backbone of DNA, but induced a conformation change of DNA leading to a disruption of duplex structure. In the following time, the complex decomposed and the end product was Cr(Ⅲ), Cr(Ⅲ) can cross-link with DNA, the whole process needs about an hour. Conclusion The chromium(Ⅴ) intermediate complex of the conformation change reaction of chromium(Ⅵ) and glutathione may play an important role in inducing the DNA.

Objective:To evaluate the results of repairing furcation and root perforation using Mineral Trioxide Aggregate(MTA).Methods:Cases with furcation perforations were divided into two groups randomly,MTA and IRM(control group)methods were adopted in present study.Cases that had root perforations were treated with MTA.Pretreatment,immediate posttreatment,and 1year follow-up radiographs were evaluated in a double-blind manner to determine the presence or absence of any pathologic changes adjacent to the perforation site.Results:21 cases were involved.The healing rate of furcation perforation in MTA group was higher(80%)when compared with that in IRM group(75%).However,statistical analysis showed no significant difference in success rates between both groups(P=0.722).The healing rate of root perforation using MTA was 100%.Conclusion:MTA provides an effective seal of furcation /root perforations,and promises in improving the prognosis of perforated teeth.

Objective To determine the serum levels of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in patients with systemic lupus erythematosus (SLE) and their clinical significances. Methods The serum concentrations of MMP-9 and TIMP-1 were measured by ELISA in 46 patients with SLE and age- and sex-matched normal controls. Results ①Serum levels of MMP-9 was significantly decreased in patients with SLE compared with those in normal controls (P

Objective To investigate the clinical efficacy of LigaSure vessel sealing system(LVSS)in laparoscopic splenectomy(LS).Methods From August 2005 to September 2006,11 cases underwent LS with LVSS.LVSS was applied to cut off lienocolic ligament and gastrosplenic ligament,and separate splenic artery from the superior border of spleen tail and blocked by an absorbable clip,and then splenic stalk was separated and cut off near the hilum of spleen with LVSS.Results LS was successfully completed in 10 cases,in which 9 with LVSS entirely,and 1 case used Endo-GIA due to difficulties in splenic stalk separation.And one case was converted to laparotomy for close adhesion of spleen with the surrounding tissues.The operation time was 60-150 min,110 min in average;blood loss was 80-400 ml.No complications such as postoperative massive hemorrhage,pancreatic leakage,or gastric leakage occured.Conclusions Application of LVSS in LS is characterized by safety,reliable hemostasis,and leaving no internal foreign body.

AIM: To evaluate the effect of replacing fetal cattle serum with umbilical cord plasma and application of OK-432 on dendritic cells from umbilical cord blood in vitro so as to offer a new technical way of preparation high-powered dendritic-cell-based vaccines for the cancer immunotherapy.METHODS: Human cord blood mononuclear cells(CBMCs) were cultured in RPMI-1640 containing 10% autologous plasma,GM-CSF and IL-4,some of which were supplemented with tumor lysates and/ or OK-432.MTT assay was applied to measure the antigen presenting ability of DCs in allo-MLR.Killing rates of autologous T lymphocytes induced by DCs on different target cells were measured by LDH method.RESULTS: Cells appeared typical morphology of DCs after culture and the allo-stimulate capacity of DCs and the CTL response in vitro were enhanced by treating with tumor lysates and OK-432.CONCLUSION: Mature DCs can be induced from human CBMCs by this means with fewer cytokines and less time.The tumor lysate antigens are captured by DCs treated with tumor lysates and OK-432,and presented to lymphocytes successfully,indicating a new way to develop dendritic-cell-based vaccines for clinical immunotherapy of gastric cancer and other tumors.

Objective To investigate the normal anatomy and variation of Willis circle by 64-slice volume CT digital subtraction angiography(VCTDSA).Methods VCTDSA data of 174 patients with cephalocervical and cephalic scanning in our hospital from February 2006 to September 2008 were analyzed.Developmental condition,shape,size,integrity,and perforating branches of Willis circle were observed.Results(1) Hypoplasia was displayed in any component vessels of Willis circle.Incidence rate of hypoplasia was 20.1% in left posterior communicating artery,16.1% in right posterior communicating artery,13.8% in right anterior cerebral artery A1,9.2% in right posterior cerebral artery P1,7.3% in anterior communicating artery,6.3% in left posterior cerebral artery P1,and 3.4% in left anterior cerebral artery A1.Congenital arterial absence occurred more frequently in right posterior communicating artery(54.6%),left posterior communicating artery(52.3%),and anterior communicating artery(15.8%).(2) Hypoplasia or congenital absence of posterior circulation and anterior-posterior circulation occurred with a rate of 55.8% and 29.8% respectively.Integrity of Willis circle was only 9.2%.There were 17 perforating branches and 26 heubner inversion arteries observed in 174 Willis circle,with an average diameter of 0.82 mm and 0.94 mm respectively.Conclusion VCTDSA can display Willis circle completely and clearly.Using three-dimensional rotation may detect all kinds of variation and perforating branches of Willis circle.

BACKGROUND:Compared with hydroxyapatite materials and other nano-hydroxyapatite composites, carbon fiber-reinforced nano-hydroxyapatite/polyamide 66 composites have been significantly improved in the mechanical strength, toughness, elastic modulus and other aspects. It can be used for repairing bone defects of loading parts. OBJECTIVE:To investigate the biocompatibility of carbon fiber-reinforced nano-hydroxyapatite/polyamide 66 composites in bone tissues. METHODS:Eight Bama mini pigs were taken to establish models of thoracic vertebral defects and implanted with carbon fiber-reinforced nano-hydroxyapatite/polyamide 66 composites. At 8, 16 and 24 weeks after implantation,the animals were sacrificed, respectively, for bone mineral density detection and hematoxylin-eosin staining. Blood samples for kidney and liver function tests were taken before and 1 and 8 weeks after implantation. RESULTS AND CONCLUSION: Hematoxylin-eosin staining of bone samples showed that the materials could bond with the bone defect interface without rejection, and could induce osteogenesis of chondrocytes. At 8 weeks after surgery, the broken ends of cancelous bone closed and the composite material was wrapped by granulation tissues. At 16 weeks after surgery, granulation tissues were organized and new bone developed directly from fibroblast cels. The new bone tissues were nearly fused with the end of cancelous bone. At 24 weeks after surgery, new bone tissue became mature lamelar bone, and the end of cancelous bone was connected tightly with the composite material. Bone mineral density of the implanted vertebra showed an increase trend at 8, 16 and 24 weeks after implantation. Over time, the bone mass was increased. The liver and kidney function tests showed that there was no significant difference before and after implantation. It is preliminarily believed that the carbon fiber-reinforced nano-hydroxyapatite/polyamide 66 composite has excelent histocompatibility and bioactivity without hepatic toxicity and nephritic toxicity.

Objective To identify the expression pattern of IGF-1 and IGF-1R in NK/T-cell lymphoma (NK/TCL) cell lines and to investigate the role of IGF-1/IGF-1R signaling in regulation of cell migration and invasion.Methods RT-PCR and immunofluorescence were performed to detect the expression of IGF-1 and IGF-1R.Transwell assay was applied to observe the effects of IGF-1/IGF-1R signaling and downstream kinases activities on cell migration and invasion.Concentrations of MMP-2 and MMP-9 were quantified by ELISA.Results Co-expression of IGF-1 and its receptor IGF-1R were identified in two NK/TCL cell lines,SNK-1 and SNK-6,while normal NK cells lack the IGF-1R expression.IGF-1R inhibitors significantly reduced SNK-1 and SNK-6 cells migration and invasion rates.Exogenous IGF-1 promoted both cell lines migration and invasion,but these effects were both blocked by IGF-1R inhibitors.Inhibition of AKT,p38 and JNK,the possible IGF-1R downstream kinases,reduced cell migration rates.Further more,exogenous IGF-1 significantly increased MMP-2 and MMP-9 secretion,while decreased secretion of MMP-2 and MMP-9 were observed when IGF-1R inhibitors were applied.Conclusion An autocrine IGF-1/IGF-1R signaling loop is aberrantly expressed on NK/TCL cells and the autocrine loop significantly promotes cell migration and invasion through activation of p38,PI3K and JNK signaling and enhances secretion of MMP-2 and MMP-9.

Objective To investigate the relationship between serum level of MMP-9(matrix metalloproteinase-9) and the disease activity of systemic lupus erythematosus(SLE).Methods Serum level of MMP-9 of 30 controls and 36 SLE patients were measured by Enzyme Linked Immuno Sorbent Assay.Results Significantly decreased serum level of MMP-9 was found in SLE patients as compared to that in healthy controls(108?113) ng/ml vs (352?155) ng/ml (P0.05).Conclusion The present data suggests that MMP-9 may be involved in the pathogenesis of SLE,and serum MMP-9 level may be a marker of disease activity,renal damage,disease progression and amelioration in SLE.

Objective To explore the related factors of hepatitis B virus(HBV) drug resistance and their clinical significance . Methods The retrospective analysis was performed on the dinical data in 153 cases of CHB in our hospital during 2011-2013 .The 8 viral drug resistance loci of 4 known nucleosides analogues lamivudine ,adefovir ester ,entecavir and telbivudine were performed the direct sequencing by using the double DNA end termination method(Sanger method);the related clinical factors of drug‐resist‐ant virus genotypes were statistically analyzed and the correlation between prognosis and drug resistance was analyzed .Results A‐mong 153 patients with CHB ,47 cases(29 .8% ) appeared virus genotype drug‐resistant ,the common sites were 204M‐I(18 cases) , 204M‐V(8 cases) ,followed by 181A‐T(10 cases) ,181A‐V(5 cases) ,then 180L‐M (14 cases) .The proportion of viral drug resist‐ance in the patients with family history ,HBeAg positive ,using the nucleotide analogues in the past and the baseline ALT≥5 times was significantly increased ,the incidence rates were 38 .8% ,34 .8% ,34 .6% and 50 .0% respectively .The multivariable COX re‐gression found that HBV‐DNA genetic drug resistance increased the risk of progression to cirrhosis of the liver ,the OR value was 4 .704(95% CI:1 .199 -18 .454) .Conclusion the Sanger method for direct sequencing is reliable and accurate method of HBV‐DNA genotype drug resistance .The proportion of viral drug resistance in the patients with a family history of hepatitis B ,HBeAg positive ,using nucleotide analogues and baseline ALT≥5 times is significantly increased;HBV‐DNA genotype drug resistance also increases the risk of progression to cirrhosis of the liver .