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 toxic effect of lung and mechanism induced by silver nanoparticles(Nano-Ag),zinc oxide nanoparticles(Nano-ZnO)and titanium dioxide nanoparticles(Nano-TiO2) on rats.Methods Forty-two Wistar rats were divided into 7 groups randomly,including the control group,low(3.5 mg/kg) and high(17.5 mg/kg) dose groups of three nanomaterials.The rats were exposed by intratracheal instillation once two days for 5 weeks,and then killed by abdominal aorta bloodletting.The pathological examinations of rat lungs were performed,malondialdehyde(MDA),superoxide dismutase(SOD),reduced glutathione(GSH),nitrogen oxide(NO),interleukin-1(IL-1),interleukin-6(IL-6),tumor necrosis factor-?(TNF-?) and macrophage inflammatory protein(MIP-2) in bronchoalveolar lavage fluid(BALF) were detected.Results The results of histopathological analysis indicated that the fibrous tubercle,pulmonary alveoli destruction and the matrix inflammation of lung tissue appeared in the exposure groups.The activities of SOD in three kinds of nanoparticles groups(except for Nano-TiO2 subgroup) significantly decreased(P

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 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.

[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.

Alzheimer disease is a common neurodegenerative disease among the elderly and has abnormal accumula-tion of amyloid plaques as the typical pathological feature.Because of its strict selective permeability,the blood-brain bar-rier prevents all macromolecular substances from entering the central nervous system and has thus become a"bottleneck"for delivering therapeutic drugs to the brain.Studies have shown that low-intensity focused ultrasound combined with ultra-sound microbubbles can safely and reversibly open the junction between endothelial cells of the blood-brain barrier through cavitation and reduce amyloid deposition by promoting the activation of microglial cells into an anti-inflammatory state.This article reviews the latest research advances in low-intensity focused ultrasound in the treatment of Alzheimer disease,in order to provide a theoretical basis and new strategies for the treatment of Alzheimer disease.