[ABSTRACT]AIM:Toinvestigatetheeffectofintracerebroventricular(icv)injectionofacidulatedartificialce-rebrospinal fluid ( aCSF ) on the respiratory reactions and the functions of acid sensing ion channels ( ASICs ) in this process.METHODS:Healthy adult SD rats (n=30) were divided into aCSF with pH 7.4 control group, aCSF with pH 6.5 group, amiloride control group, amiloride plus aCSF with pH 6.5 group, psalmotoxin 1 (PcTx1) control group and PcTx1 plus aCSF with pH 6.5 group.The electromyogram (EMG) of the diaphragm was monitored to observe the respirato-ry responses induced by icv injection of acidulated aCSF .The ASICs blockers were also injected into the lateral cerebral ventricle firstly and acidulated aCSF was injected following the ASICs blockers to observe the effect of ASICs on the respira -tory regulation by the central chemoreceptor .RESULTS:After icv injection of acidulated aCSF , the respiratory responses of the rats were excited (P<0.05).The respiratory excitation responses disappeared after icv injection of ASICs blocker amiloride.The degree of respiratory excitation was weakened after icv injection of ASIC 1a blockers-PcTx1.CONCLU-SION:ASICs play a key role in the respiratory regulation by the central chemoreceptor and ASIC 1a partly operates in this process.

BACKGROUND:It is a key to choose an appropriate method to trans-differentiated bone marrow mesenchymal stem cells (BMSCs)into neuron-like cells for clinical therapy of neural system injury.OBJECTIVE:To observe the feasibility of the differentiation of rat BMSCs supplemented with rat dentate gyrus extract(DGE)into neuron-like cells.METHODS:DGE was applied to induce rat BMSC trans-differentiation,using 20,40,60,80 mg/L protein concentration.Neuron differentiation was measured using Western blot to screen an optimal dosage.After trans-differentiation,different concentration treated cells were collected.Morphology change was observed following differentiation under an inverted microscope.Neuron specific enolase(NSE)and NeuN expression was determined using Western blot.NeuN expression in cells was detected using immunofluorescence technique.RESULTS AND CONCLUSION:After 7 days,60 mg/L DGE was the optimal induction dose detected by Western blot.With increased concentration,NSE and NeuN expression was increased.At 80 mg/L mass concentration,NSE and NeuN expression was reduced.At 60 mg/L DGE,BMSCs following induction became long,with synapses,Immunofluorescence NeuN staining found that neuron-like cells were positive for NeuN following induction.Results indicated that DGE is an effective biological inductor that can induce BMSC differentiation.

Cancer stem cell (CSC) theory supposes that CSCs are the origin of tumors occurrence, progression,drug resistance, recurrence and metastasis. Cancer is not only a genetic disease but also a stem cell disease. Increasing evidence suggests the existence of CSCs in some solid tumors.

Objective: To evaluate the mechanical properties of Rene95 alloy component made by laser engineered net shaping (LENS). Methods: The component was fabricated from Rene95 alloy powder by LENS, then the mechanical properties of the component, Rene95 alloy casting and dental Ni-Cr alloy casting were studied. Results: The tensile strength(MPa), yield strength(MPa), elongations(%) and the microhardness(Hv) of Rene 95 alloy component made by LENS were 1 354.27?63.44, 1 175.29?34.32, 16.53?5.85, and 464.33?10.95, those of Rene95 alloy casting 1 430.28?55.73, 1 145.52?29.78, 10.31?4.25 and 457.56? 11.38, those of dental Ni-Cr alloy casting 612.05?18.46, 426.06?12.70, 6.21?1.21 and 260.14? 6.08, respectively.Conclusion: The mechanical properties of Rene95 alloy component made by LENS were same as those of Rene95 alloy casting, better than dental Ni-Cr alloy casting.

objective: To study the effects of laser engineered net shaping(LENS) in the manufacture of dental prosthesis. Methods: An experiment LENS system, including a 5 kW continuous wave CO 2 laser, a four-axes numerical control working table and powder feeding system, was built up, by which, a rectangular LENS component was made from Rene95 alloy powder. The microstructure of the component was observed with scanning electron microscope and ESA analysis. Results: The size of the component was 120 mm?15 mm?15 mm , and the wall of the component was perpendicular to the base. The microstructure of the component was made up of fine columnar dendrite with the length of 10～20 ?m, 10 times less than that of the cast made from the same material. The main elements of the powder distributed homogeneously,the negative effect of segregation could be limited and the properties of the component could be improved.Conclusion: The microstructure of components made by LENS is much better than that of those made by casting from the same material.

An investigation and analysis on the effect of current bilingual teaching has been done among the 2002rd seven-year program students by using questionnaire.The result can provide basic foundation for improving the quality of bilingual teaching.

Objective To explore the effect of probucol on the inflammatory response in rabbits with arteriosclerosis obliterans.Methods SPF male new zealand white rabbits were subjected to incomplete right femoral artery ligation model of arteriosclerosis obliterans.The model rabbits were divided into experimental group and control group.The rabbits in experimental group were treated by probucol.After treatment for 4 weeks,HE staining was used to evaluate the injury severity of right femoral artery in rabbits;ELISA was used to measure the levels of IL-1,IL-6,TNF-α and CRP;Realtime PCR was used to detect the expressions of IL-1,TNF-α in right femoral artery;Western blot was used to measured the nucleus accumulations of NF-κB,and the phosphorylation of IκB.Results Compared with control group,the degree of pathological injury of right femoral artery was significantly atteunated,the levels of IL-1 、IL-6 、TNF-α and CRP in plasma,the mRNA expressions of IL-1 、TNF-α and the nucleus accumulations of NF-κB,and the phosphorylation of IκB in right femoral artery decreased significantly.Conclusion Probucol attenuates the inflammatory response in rabbits with arteriosclerosis obliterans significantly.

Objective To investigate the effects of 5-Aza-2′-deoxycytidine (5-Aza-Cde)on DNA methylation and expression of hMLH1 and MGMT gene in the human lung cancer cell line A549/DDP.Methods A549/DDP cells were cultured with RPMI 1 640 medium and were treated with 5 μmol/L DNA methyhransferase inhibitor 5-Aza-Cde.Methylation-specific pol-ymerase chain reaetioll (MSP)was used to detect the promoter methylation state of the hMLH1 and MGMT gene.RT-PCR was used to detect the mRNA expression of hMLH1 and MGMT before and after treatment with 5-Aza-Cde,respectively. Results Before treatment with 5-Aza-Cde,hMLH1 and MGMT expressions were absent,and promoter hypermethylation of the hMLH1 and MGMT gene were detected in A549 cells.After treatment with 5-Aza-Cde,the promoter region of the hM-LH1 and MGMT gene exhibited a demethylation state,and their mRNA expressions were increased.Conclusion Promoter hypermethyhtion is amajor mechanism of hMLH1 and MGMT gene silencing in human lung cancer cells,and can be reversed by the demethylating agent 5-Aza-Cde,which can regulate the expressions of the hMLH1 and MGMT gene.

To investigate the effects of genistein (Gen) on interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) secreted by fibroblast-like synoviocytes (FLSs) of rats with type II collagen-induced arthritis (CIA).

Objective To investigate the effect of L-carnitine on the apoptosis in Schwann cells induced by high glucose.Methods The cell line RSC96 cultured in vitro were seeded in 96-well plates at a density of 1.5 × 104/ml (200 μl/well) or in 6-well plates at a density of 2 × 105/ml (2 ml/well) and cultured for 24 h.The cells were randomly divided into 4 groups (n =24 each) using a random number table:normal control group (group C),high glucose group (group H),high glucose + L-carnitine group (group H + L),and mannitol osmotic control group (group M).The cells in group C were incubated in the plain culture medium containing normal glucose (5.6 mmol/L).The cells were incubated in the medium containing glucose 50 mmol/L in group H or in the medium containing glucose 50 mmol/L and L-carnitine 50 μmol/L (final concentration) in group H + L.The cells were incubated in the medium containing normal glucose (5.6 mtmol/L) and mannitol 44.4 mmol/L in group M.At 48 h of incubation,cell growth conditions were observed under inverted microscope,superoxide dismutase (SOD) activity was measured by xanthine oxidase method,malondialdehyde (MDA) content was measured by thiobarbituric acid test,cell viability was measured by MTT assay and cell apoptosis was measured by flow cytometry.The expression of activated caspase-3 and poly (ADP-ribose) polymerase-1 (PARP-1) protein was detected by Western blot.Results Compared with group C,the cell viability and SOD activity were significantly decreased,MDA content and apoptotic rate were increased,and the expression of activated caspase-3 and PARP-1 protein was up-regulated in H and H + L groups,and no significant changes were found in group M.Compared with group H,the cell viability and SOD activity were significantly increased,MDA content and apoptotic rate were decreased,and the expression of activated caspase-3 and PARP-1 protein was down-regulated in group H + L.Conclusion L-camitine can attenuate high glucose-induced apoptosis in Schwann cells by inhibiting oxidative stress responses and down-regulating the expression of activated caspase-3 and PARP-1.