Aim To investigate the protective effects of sphingosine 1-phosphate ( S1 P ) postconditioning on hypoxia/reoxygenation( H/R) injury in human umbili-cal vein endothelial cells ( HUVEC ) and its mecha-nisms. Methods HUVECs cells were divided into five groups: normal ( control) group, S1P low concentra-tion group ( L ) , S1 P medium concentration group (M), S1P high concentration group ( H) and H/R group. MTT method was used to measure cell survival. Using flow cytometric analysis, the rate of cell apopto-sis was determined. The activities of total superoxide dismutase ( T-SOD) , copper/zinc superoxide dismuta-se ( CuZn-SOD ) , manganese superoxide dismutase ( Mn-SOD) activity, nitric oxide ( NO) and malondial-dehyde ( MDA ) content in cell culture medium were measured with colorimetry. Mitochondrial membrane potential in cells was observed with fluorescence micro-scope. Bax/Bcl-2, eNOS protein expression levels in HUVECs cells were observed with Western blot. Re-sults Compared with H/R group, S1P low, medium and high concentrations in the intervention group could significantly increase the cell survival rate after H/R injury, and increase activity of T-SOD, CuZn-SOD, Mn-SOD and decrease content of MDA. Moreover, S1 P could significantly increase NO content and in-crease eNOS protein expression, decrease apoptosis rate and inhibit the reduction of mitochondrial mem-brane potential. Conclusions S1P can decrease cell apoptosis rate of HUVECs after H/R injury with a cer-tain concentration dependence. The protection of S1P for cell apoptosis of HUVECs after H/R injury may be related to decreasing the intracellular MDA content and improving intracellular SOD activity, increasing mito-chondrial membrane potential and enhancing expres-sion of Bcl-2, anti-apoptotic protein.

Objective To investigate the impact of the pretreatment perfusion weighted imaging (PWI)-diffusion weighted imaging (DWI) mismatch on reperfusion and early neurological improvement after intravenous thrombolysis in acute ischemic stroke.Methods We retrospectively reviewed our collected clinical,laboratory,and radiologic data in patients receiving intravenous recombinant tissue plasminogen activator therapy,who had performed multimodal MRI in both pretreatment and 24 h post-treatment in our hospital..The target mismatch of PWI-DWI was defined as a PWI lesion that was 10 ml or more and 120％ or more of the DWI lesion,with DWI lesion less than 70 ml and PWI lesion less than 140 ml.The smalllesion was defined as a DWI and PWI volume both less than 10 ml.The others were termed non-target mismatch.Reperfusion required a 30％ or greater reduction in PWI lesion volume on the 24-hour follow-up scar.The early neurological improvement was defined as the patients with an NIHSS score of 0 to 4 or 6-point or greater improvement at 7 days.Results Among 45 patients analyzed,19(41％) patients presented target mismatch,of which 8 patients were treated over 4.5 h.The rate of reperfusion and early neurological improvement after thrombolysis in target mismatch group were both significantly increased comparing with non-target mismatch group( 16/19 vs 5/12,x2 =6.092,P ＜0.05 and 13/19 vs 2/12,x2 =7.888,P ＜ 0.05,respectively ),although the recanalization rate demonstrated no significant difference between two groups.The pooled OR for reperfusion was 6.4(95％ CI 1.156-35.437,P =0.034),and the pooled OR for favorable clinical response was 21.7 ( 95％ CI 2.234-210.110,P =0.008 ) in target mismatch patients.Among the target mismatch group,13/16 of patients with reperfusion had early neurological improvement,while no patients without reperfusion had neurological improvement.The rate of recanalization,reperfusion and neurological improvement after thrombolysis demonstrated no significant difference between target mismatch group treated within 4.5 h and beyond 4.5 h.Conclusion Patients with target mismatch profile before thrombolysis had a high reperfusion rate and were prone to get early neurological improvement,indicating that the evaluation of PWI-DWI mismatch may facilitate the selection of patients who may benefit from thrombolysis beyond the time window.

Aim To study the protective effects of sphingosine 1-phosphate (S1P) postconditioning on rat myocardial cells injured by hypoxia/reoxygenation in reperfusion injury salvage kinase ( RISK ) signal path-way. Methods The cultured rat H9c2 cells were ran-domly divided into seven groups: ( 1 ) control group;(2) hypoxia/reoxygenation (H/R) group; (3) S1P group;(4) S1P+LY294002 group(S1P+LY); (5) LY group; ( 6 ) S1 P +PD98059 group ( S1 P +PD );(7) PD group. The viability of H9c2 cells was detec-ted using MTT method. The content of MDA in the cultured medium and the activity of T-SOD and Mn-SOD were measured with colorimetry. The concentra-tion of intracellular free calcium ion was detected by confocal microscopy. The rate of cell apoptosis was de-termined by flow cytometric analysis. Western blot was used to assess phosphorylation of Akt and ERK1/2 in H9c2 cells. Results Compared with the H/R group, S1P significantly increased vaibility of cells, lowered the rate of apoptosis, decreased the content of MDA in the culture medium, increased the activity of T-SOD and Mn-SOD, reduced concentration of intracellular calcium and increased the phosphorylation of Akt and ERK1/2 . When added LY294002 or PD98059 , the effects of S1P above were inhibited. Conclusion S1P protects H9 c2 cells against hypoxia/reoxygenation inju-ry. The protection of S1P was inhibited by LY294002, the inhibitor of PI3 K/Akt and PD98059 , the inhibitor of ERK1/2 . S1 P protects H9 c2 cells against hypoxia/reoxygenation injury via RISK pathway.

Objective To investigate the safety and efficacy of intravenous thrombolytic therapy with recombinant tissue plasminogen activator(rtPA)in patients with isolated penetrating artery territory infarct (IPAI).Methods Data of retrospectively collected clinical,laboratory,and radiological from 75 consecutive patients with acute ischemic stroke treated with intravenous rtPA therapy from June 2009 to April 2011.Etiological classification was carried out according to the Chinese Ischemic Stroke Classification of Subgroups(CISS).The rates of hemorrhagic transformation(HT)and clinical outcomes of patients were compared between IPAI group and non-IPAI group.Results All 75 patients with mean age of 67.4years and 25(33.3％)fenale,were treated with intravenous rtPA.Before treatment,their average score of the National Institutes of Health Stroke Scale(NIHSS)was 12.3 ± 6.4,and mean length of time from onset to treatment was 239.6 ±97.5 minutes.After thrombolytic therapy,the radiological HT was found in 24 patients(32％).Symptomatic intracraneal hemorrhage(ICH)occurred in 4 patients(5.3％).Of 22 (29.3％)patients with IPAI,only one experienced HT.Logistic regression analysis suggested that IPAI wasan individualized predictor used alone for determining the low risk of HT.In the patients with IPAI,82％ of them had an individual clinical outcome(mRS ＜ 2)one month after onset,and the neurological outcomes were better in patients with IPAI than those in patients with non-IPAI(P ＜ 0.01).Conclusions The risk of hemorrhagic complication was low and the clinical outcome was good in patients with isolated penetrating artery territory infarct after intravenous thrombolytic therapy with rtPA.Imaging diagnosis of IPAI might facilitate the treatment with rtPA in this cohort of patients.

Background and objectivehTe prognosis for patients with lung cancer and brain metastases remains poor, with approximately 6 months of survival, despite active measures atfer treatment. In this study, we determined and ana-lyzed clinical parameters that affect the survival of patients with lung cancer and brain metastases to provide clinical guidance. MethodsLung cancer cases with brain metastases were retrospectively collected during 2002 and 2008 from Shanghai Chest Hospital, Shanghai Jiao Tong University.Kaplan-Meier method andCox regression were performed for univariate and multi-variate analyses, respectively, to explore independent predictors inlfuencing the survival of patients with lung cancer and brain metastases.Results Age, Eastern Cooperative Oncology Group performance status (ECOG PS), metastasis interval, number of metastasis, treatment method, treatment period, symptoms of brain metastases, extracranial metastasis, and brain metastasis order were factors that affect the survival of patients with brain metastases as conifrmed through theKaplan-Meiermethod. Treatment periods and extracranial metastasis were independent survival predictors in patients with lung cancer and brain me-tastasis as indicated byCox proportional hazard model.ConclusionTreatment periods and extracranial metastasis were inde-pendent predictors of survival of patients with lung cancer and brain metastasis. Treatment periods and extracranial metastasis were independent predictors of survival of patients with lung cancer and brain metastasis.

Objective:At present,the doctor-patient relationship is tense.The prevalence of negative emotions,such as depression and anxiety,among healthcare workers is increasing every year.Negative attitudes of medical workers toward mental problems may aggravate the doctor-patient conflict and psychological problems of medical workers.This study aims to explore the complex network relationships between outpatient medical workers'attitudes toward mental problems,doctor-patient relationships,and their depression/anxiety levels. Methods:A total of 578 outpatient medical staff from the Second Xiangya Hospital of Central South University(167 males,411 females)completed questionnaires on their attitudes toward mental problems,doctor-patient relationships,and depression/anxiety symptoms.Network analysis was conducted separately to construct the"attitude towards mental problems-doctor-patient relationship network"and"depression-anxiety related network". Results:The edge between"M15(insulting words)"and"D8(waste time)"showed the strongest strength in the"attitude towards mental problems-doctor-patient relationship network",and"M15(insulting words)"had the highest bridge strength in the network.For the analysis of emotional variables,"P1(anhedonia)"showed the most obvious association with"D10(communication difficulties)"in the doctor-patient relationship and"M2(poor quality of life)"in the psychiatric attitudes,and"P1(anhedonia)"was the key bridge symptom in the network. Conclusion:The"insulting words"may be an intervention target for medical workers'attitudes toward mental problems.The"anhedonia"in depression is the potential symptom that needs to be treated.Intervention targeting these variables may be beneficial to improve the mental health level of medical workers and the doctor-patient relationship.

Objective:To investigate the influence of digital light processing (DLP) and computer numerical controlmilling (CNC) on the mechanical behavior of zirconia.Methods:Prepared DLP samples (experimental group, n=52) and CNC samples (control group, n=52) with 12 samples in each group were randomly selected using random number table to measure density, grain size and crystal phase composition. According to the different methods fracture toughness test, the samples were divided into indentation method group (IM) and single-edge-V-notch-beam group (SEVNB), with 30 DLP and 30 CNC samples in IM group, 10 DLP and 10 CNC samples in SEVNB group. The IM group was tested under three different loads (49.03 N, 98.07 N, 196.10 N), there were 10 samples for each load and each sample was tested at 15 points, and the load with the ratio of crack length to indentation diagonal length greater than 2.5 was selected as the indentation load to calculate its IM fracture toughness. At the same time, the SEVNB group was tested with four point bending test to record the maximum load at the time of fracture and calculate the SEVNB fracture toughness. Finally, the indentation and fracture surface were observed using optical microscope and scanning electron microscope, and the results of DLP group and CNC group were further compared to explore the difference in fracture mechanism. Results:The microstructure of DLP and CNC zirconia was basically the same, the density of DLP group was (6.020±0.021) g/cm 3, the grain size was (0.603±0.033) μm; the density of CNC group was (6.038±0.012) g/cm 3, the grain size was (0.591±0.033) μm. Both groups were composed of tetragonal zirconia. The load of 196.10 N was chosen as the indentation load for two groups to calculate the IM fracture toughness. In terms of fracture toughness, there was no significant difference between the two groups ( P>0.05). Scanning electron microscope images of fracture surface showed the intergranular fracture was the leading fracture mode of two groups. The IM and SEVNB fracture toughness of DLP zirconia were (6.111±0.179) MPa·m 1/2 and (7.221±0.809) MPa·m 1/2, respectively. The IM and SEVNB fracture toughness of CNC zirconia were (6.126±0.383) MPa·m 1/2 and (7.408±0.533) MPa·m 1/2, respectively. Conclusions:The microstructure of DLP and CNC zirconia is almost the same, and there is little difference in the fracture toughness of zirconia between two processing technologies.