The antibacterial property of silver nanoparticles has resulted in their widespread application in many fields,so the chance of silver nanoparticles exposure for human increased greatly.Thus,there is urgent need to assess the safety of such particle.So far,most toxicological studies of silver nanoparticles mainly focus on the cytotoxicity using different examination endpoint such as morphology,mitochondrial function,cell proliferation,enzyme activity,and so on.In addition,the in vitro studies on the toxicity of silver nanopoarticles are also reported,few of the study on molecule mechanism of toxicity was reported.This review provided a summary of antibacterial mechanism of silver nanoparticles and the current research situation of the safety.The future research direction of toxicological study of silver nanoparticles is also prospected based on the current knowledge.

Objective To investigate the effect of different doses of lidocaine on expression of the high mobility group box 1 protein (HMGB1) in small intestine in septic rats.Methods Fifty adult male Wistar rats weighing 200-250 g were randomly divided into 5 groups ( n =10 each):sham operation group (group S),sepsis group( group Sep ) and different doses of lidocaine group (group L1～3 ).Group S were not applied cecal ligation and puncture (CLP).Sepsis intestinal damage model was performed in group Sep by CLP.Group L1～3 were given intraperitoneally lidocaine in a dose ofS,10 and 20 mg/kg at immediately,1 and 2 h after CLP,respectively.Isometric normal saline was given intraperitoneally in group S and group Sep.The small intestine tissues were taken at 24 and 48 h after CLP.The small intestine morphology was observed with optical microscope.The expression of the HMGB1 mRNA were examined by PCR and the activity of diamine oxidase (DAO) were determined by ELISA.Results Compared with group S,the expression of HMGB1 mRNA was increased and the activity of DAO decreased in group Sep and groups L1～3 at 24 and 48 h after CLP ( P ＜ 0.05 ).Compared with group Sep,the expression of HMGB1 mRNA was decreased and the activity of DAO increased in a dose-dependent manner in groups L1～3 ( P ＜0.05),The injury of pathology of small intestine was slighter in groups L1～3 than in group Sep.Conclusion Lidocaine can reduce samll intestine injury through inhibiting HMGB1 expression in septic rats by a dose-dependent manner.

Objective To investigate the effect of lidocaine on the LPS-induced NF-κB activity in rat peritoneal macrophages. Methods The peritoneal macrophages obtained from male Wistar rats were placed in 12-well plates at 2 × 106 cell/ml after being cultured for 3 days. Each well contained 1 ml of cell suspension. The cells were randomized into control group (group C), LPS group and 3 LPS + lidocaine group S (group LL1.2.3)(n = 10 wells each). In group LPS and LL1,2,3, the cells were exposed to LPS 100 ng/ml. In group LL1,2,3 the cells were exposed to lidocaine 2, 20 200 kg/ml respectively in addition to LPS 100 ng/ml. After being incubated for 24 h, the HMGB1 concentration in the supernatant (by ElISA) and HMGB1 mRNA expression (by RT-PCR)and NF-κB activity in the cells were measured. Results LPS signiticantly increased HMGB1 concentration,HMGB1 mRNA expression and NF-κB activity in the supernatant. Lidocaine treatment significantly attenuated the LPS-induced increase in HMGB1 concentration HMGB1 mRNA expression and NF-κB activity in a dose-dependent manner. Conclusion Lidocaine can inhibit NF-κB activity in the rat peritoneal macrophages and in turn inhibit the synthesis and release of HMGB1.

Objective To investigate the effects of different doses of lidocaine on acute liver injury in septic rats.Methods Fifty male Wistar rats,weighing 200-250 g,aged 8-10 weeks,were randomly divided into 5 groups(n =10 each):sham operation group(group S),sepsis group(group CLP),and different doses of lidocaine groups(groups L1-3).Sepsis was induced by cecal ligation and puncture(CLP)in anesthetized rats.At 0,1 and 2 h after CLP,lidocaine 5,10 and 20 mg/kg(in normal saline 0.5 ml)were injected intraperitoneally in groups L1-3 respectively,while normal saline 0.5 ml was given in groups S and CLP.At 24 h after CLP,blood samples were taken for determination of the plasma alanine aminotran sferase(ALT)concenlralion.The rats were then sacrificed,and the liver was removed for microscopic examination and determination of the hepatic high-mobility group box 1 protein(HMGBI)mRNA expression.Results Compared with group S,the plasma ALT concentration was significandy increased and hepatic HMGBI mRNA expression was up-regulated in groups CLP and L1-3(P ＜ 0.05).Compared with group CLP,HMGBI mRNA expression was down-regulated in groups 14-3,while the plasma ALT concentration was decreased in groups L2 and L3(P ＜ 0.05),The plasma ALT concentration was significantly decreased and HMGBI mRNA expression was down-regulated in groups L2 and L3 com pared with group L1,and in group L3 compared with group L2(P ＜ 0.05).The microscopic examination showed that the pathologic changes were attenuated in groups L1-3,and the changes were least severe in group L3.Concluslon Lidocaine can reduce acute liver injury in septic rats,this effect is dose-related,and inhibition of hepatic HMGBI mRNA expression is involved in the mechanism.

Objective To investigate the role of high mobility group protein box 1 (HMGB1) in pulmonary vascular remodeling in a rat model of acute lung injury (ALI).Methods Thirty healthy pathogen free male Wistar rats weighing 220-250 g were randomly divided into 3 groups (n =10 each) ∶ group control (group C) ;group LPS (group M) and group LPS + HMGB1 antibody (group H).The animals were anesthetized with intraperitoneal 10％ chloral hydrate 7 ml/kg.ALI was induced with LPS 1 mg/kg infused iv over 30 min in groups M and H.In group H HMGB1 antibody 2 mg/kg was injected iv at 12,24 and 36 h after LPS administration respectively.The animals were sacrificed at 72 h after LPS administration.The left lung was removed for microscopic examination,measurement of the thickness of the medial layer (tunica media) of pulmonary arterioles and determination of the expression of PCNA (by immune-histochemistry) and HMGB1 protein (by Western blotting).Results The medial layer of pulmonary arterioles was significantly thicker and the expression of PCNA and HMGB1 higher in group M than in group C.LPS also induced significant inflammatory cell infiltration within the alveoli and damage to the septa.In group H HMGB1 antibody significantly attenuated the above-mentioned LPS-induced changes.Conclusion HMGB1 may play an important role in the LPS-induced pulmonary vascular remodeling.

Objective To compare the clinical effect of manual aspiration thrombectomy versus systemic thrombolysis for acute lower extremity deep venous thrombosis of mixed type.Methods The clinical data of 380 patients with acute lower extremity deep venous thrombosis of nixed type was analyzed retrospectively,who were classified into two groups according to treatment methods.Group A (229 cases):the ipsilateral femoral vein was accessed under local anesthesia,a 12-14 F sheath was introduced via a guide wire to aspirate iliofenoral thrombus.As for the femoropopliteal thrombus,a Fogarty balloon catheter was introduced to pull thrombus to iliac vein,then mechanical aspiration thrombectomy was performed.One hundred and thirteen patients with stenosis or occlusion of comnon iliac vein were treated with adjunctive PTA and stenting.As for the residual thrombus bclow popliteal vein,a small dose urokinase vas given to thrombolysis and heparin anticoagulation after procedure.Group B(151 cases) were treated by systemic thrombolysis and anticoagulation with heparin.Results The swelling and pain of affected limbs of group A began to relief after operation immediately,but these times of group B was 3-7 days after operation.The thrombus was eliminated completely(Grade Ⅰ):goup A was better than group B (63.32％ vs 37.09％) (x2 =20.53,P =0.002).Conclusions The manual aspiration thrombectomy was superior to simple systemic thrombolysis in treating acute lower extremity deep venous thrombosis of mixed type,especially in protecting the normal valve function that was better than thrombolysis,aspiration thrombectomy with adjunctive iliac vein angioplasty was a more reasonable method to treat acute LEDVT.

AIM: To investigate the effects of pseudolaric acid B on the growth and apoptosis of glioblastoma cell line U87.METHODS: The cell morphological changes were observed under inverted microscope.The cell viability was evaluated by MTS assay.The cell cycle was analyzed by flow cytometry and Western blot.The cell apoptosis was de-tected by flow cytometry.The changes of apoptosis-related proteins cleaved PARP, caspase-3, procaspase-9 and caspase-8 were determined by Western blot.RESULTS: Pseudolaric acid B inhibited the viability of U87 cells, arrested U87 cells in mitosis.Apoptosis of U87 cells was induced by pseudolaric acid B.The caspase pathway was activated.CONCLUSION:Pseudolaric acid B induces glioblastoma cell line U87 mitotic arrest and apoptosis.

[Objective] To investigate the association between -31C/G polymorphism in the promoter of survivin gene and the susceptibility to sporadic colorectal cancer in southern Chinese population. [Methods] Survivin-31C/G genotypes were determined by polymerase chain reaction-restriction fragment length polymorpbism (PCR-RFLP) in 711 healthy controls and 702 CRC cases. [Results] The number of CRC patients carrying with CC genotype was much higher than those of controls (36.5 % vs. 26.12%, X~2=17.89, P<0.001). Compared with CC genotypes, CG, GG genotypes and G allele carriers had a significantly decreased risk of CRC, with the decrease being 0.61-fold (95% CI=0.46-0.81, P<0.001), 0.52-fold (95% CI=0.38-0.71, P<0.001) and 0.58-fold (95% CI=0.45-0.74, P<0.001), respectively. [Conclusion] Survivin gene -31C/G polymorphism is associated with sporadic CRC risk, the G variant genotypo is the independent protective factors against sporadic CRC in soutbem Chinese population.

AIM: To investigate the association between -31C/G polymorphism in the promoter of survivin gene and the susceptibility to sporadic colorectal cancer (CRC) in southern Chinese population. METHODS: survivin -31C/G genotypes were determined by PCR-RFLP in 711 healthy controls and 702 CRC cases. RESULTS: The number of CRC patients carrying with CC genotype was much higher than that of controls (36.5 % vs 26.2%,χ~2 =17.89,P<0.01). Compared to CC genotypes, CG, GG genotypes and G allele carriers had a significantly decreased risk of CRC, with the decrease being 0.61-fold (95% confidence interval=0.46-0.80, P<0.01), 0.52-fold (95% confidence interval=0.38-0.71,P<0.01) and 0.58-fold (95% confidence interval=0.45-0.74, P<0.01), respectively. CONCLUSION: survivin gene -31C/G polymorphism is associated with sporadic CRC risk, the G variant genotype is the independent protective factors against sporadic CRC in southern Chinese population.

Objective To discuss the effects of lidocaine infusion on perioperative immune function by evaluating the levels of stress hormone and natural killer (NK) cell cytotoxicity.Methods Thirty-five patients of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,aged 35-65 yr,undergoing elective radical hysterectomy,were randomized into lidocaine group (group L)and control group (group C).Fifteen minutes before anesthesia induction,a bolus of 1.5 mg/kg of lidocaine was administered iv.to each patient in group L and followed by a continuous infusion at 1.5 mg·kg-1 ·h-1 lasting to the end of surgery.Meanwhile,the patients in group C received the same volume of saline.Venous blood samples were collected individually 24 h before the operation,the end of the operation and 48 h after the operation.Levels of prostaglandin,epinephrine and norepinephrine were assayed by ELISA kits.NK Cells were obtained by CD56 antibody magnetic isolation.The cytotoxicity of NK cell was detected by LDH releasing assay,and phosphor-protein kinase A (p-PKA)and protein kinase A (PKA) were detected by Western blotting.Results There were no significantly different in the plasm levels of PGF2,EP1 and NE.The plasm levels of prostaglandin (562.5±98.2 vs.663.2±119.0) pg/ml,epinephrine (24.9±4.8 vs.29.7±3.5) pg/ml and norepinephrine (408.3 ±47.2 vs.499.6±45.6) pg/ml in patients of group L were lower than those in group C (P＜0.05)48 h after the surgery.The cytotoxicity of NK cell was higher in group L than that in group C (44.1 ±5.0 vs.37.1±5.5)％ (P＜0.05) 48 h after the surgery.The ratio of p-PKA/PKA was lower in group L than that in guoup C (0.060±0.008 vs.0.099±0.011) (P＜0.05) at the end of the surgery.Conclusion Perioperative intravenous lidocaine infusion can reduce the level of plasma catecholamine and PGE2,and protect the cytotoxicity of NK cell,possibly via inhibiting of cAMP-PKA signaling pathway.