Objective To investigate the effect of cyclic tensile stress (CTS) on the metabolism inand apoptosis of rat chondrocytes.Methods Primary rat chondrocytes were cultured on a Bioflex plate for one day and then stretched cyclically for 24 hours at a frequency of 0.5 Hz using a Flexcell-5000T apparatus.The cells were divided into 5 groups according to their stretching ratio:0％ (the control group),2％,6％,10％ and 14％.After the stretching,Col Ⅱ,Aggrecan,MMP-13 and ADAMTS-5 mRNA were measured using qPCRs,and the NO and PGE2 levels were measured using ELISA kits.Moreover,TUNEL staining and Annexin V-FITC/PI were used to analyze the apoptosis of chondrocytes.Results Compared with the control group,the average levels of Col Ⅱ and Aggrecan mRNAdecreasedin 10％ and 14％ groups [(0.738±0.11) and (0.58±0.13),(0.75±0.11) and (0.55±0.09)].In those groups,the MMP-13 [(2.47±0.47) and (2.88±0.36)] and ADAMTS-5 mRNA level [(2.39±0.33) and (2.75±0.49)],the NO [(6.96±0.96) and (8.28±0.82)] and PGE2 level [(6.83±0.66) and (7.15±0.71)] had increased significantly.In the 6％ group the average levels of Col Ⅱ(1.76±0.30) and Aggrecan mRNA (1.93±0.14)of 6％ group were significantly higher than the control group,but the NO level of the former (3.07±0.20) was significantly lower than the control group (3.89 ± 0.33).The apoptosis rate of chondrocytesin 2％ and 6％ groups were (0.065±0.013) and (0.063 ± 0.147),without significant differences to that of the control group (0.045 ± 0.008).However,compared with the control group,apoptosis in the 10％ and 14％ groups [(0.135 ±0.026) and (0.184±0.020)] increased significantly.Conclusion The effect of cyclic tensile stress on chondrocyte metabolism and apoptosis was magnitude-dependent.Ten percent and 14％ CTS can increase the catabolism and apoptosis of chondrocytes.Ten percent and 14％ strain can increase the catabolism and apoptosis of chondrocytes.Cyclic 6％ strain can increase the anabolism of chondrocytes,but 2％ strain has no impact on metabolism or apoptosis.

Objective To investigate the role of neuroglobin ( NGB) in oxygen-glucose deprivation and reoxygenation ( OGD/R ) induced mitochondrial depolarization and reactive oxygen species ( ROS ) production in a human neuroblastoma cell line (SH-SY5Y).Methods SH-SY5Y cells were transfected with lentivirus to establish a stable cell line of NGB knockdown ( KD).After treated with OGD/R, cells were collected at different time points to analyze NGB mRNA and protein levels.Furthermore, cells were stained with JC-1 and DCFH-DA to evaluate mitochondrial depolarization and ROS production by inverted fluorescence microscope.Also, to determine the neurotoxicity , we measured the lactate dehydrogenase ( LDH) level in the cell culture medium.Results After the treatment of OGD/R, the NGB mRNA and protein started to elevate and peak at 4 h and 8 h (2.04 ±0.35 fold,1.69 ±0.18 fold).Compared with the vector group , NGB KD group had much more mitochondrial depolarization [ JC-1 red/green ( 1.10 ±0.10 ) vs (1.46 ±0.11),P<0.05] and ROS production [DCFH-DA fluorescence (36.30 ±5.32) vs (16.26 ± 2.97),P<0.05].Furthermore, NGB KD groups had a higher level of LDH release [(63.42 ±6.14)%vs (49.65 ±5.09 )%, P <0.05 ].Conclusions NGB plays an important role in the homeostasis of mitochondria.Knockdown of NGB results in increased mitochondrial depolarization , ROS production and neurotoxicity under hypoxia circumstances.

Objective:To investigate the effects of Cordyceps sinensis (CS) on cellular apoptosis and Sirt1 expression in HK2 cells followed by ischemia-reperfusion (I/R).Methods:HK2 cells were incubated with different concentrations of CS (10,20,40,80,160,320 mg/L) for 24 hours,and the optimal concentration of CS was selected by measuring cell proliferation.The confluent HK2 cells were incubated with 0.01 μmol/L antimycin A for 2 hours to induce ischemia in vitro,and then the reperfusion was achieved by incubating cells with glucose-replete complete growth medium for 24 hours.HK2 cells were divided into 4 groups:a control group,an I/R group,an I/R+CS (160 mg/L) group,and an I/R+CS (160 mg/L)+Sirtinol (25 μtmol/L) group.Twenty-four hours later,total RNA and protein were collected.The cell proliferation was evaluated by MTT assay;the mRNA and protein expression of Sirtl and the cleaved caspase-3 were measured by qRT-PCR and Western blot,respectively.The cellular apoptosis rate was determined by Annexin V-FITC/PI double staining and flow cytometry.Results:Certain concentrations (10-160 mg/L) of CS did not show effect on the proliferation of HK2 cells (P＞0.05),while 320 mg/L of CS inhibited cell proliferation significantly (P＜0.01);compared with the control group,the mRNA and protein expressions of Sirtl and the cleaved caspase-3 in the I/R group were up-regulated (P＜0.01) and the apoptosis rate was extremely high;compared with the I/R group,CS significantly up-regulated Sirt1 mRNA and protein expression (P＜0.01) while down-regulated cleaved caspase-3 mRNA and protein levels (P＜0.01),and reduced apoptosis rate (P＜0.05).The effects of CS were blocked in the presence of sirtinol,an inhibitor of CS.Conclusion:CS protects HK2 cells from I/R injury through activation of Sirt 1 pathway.

To explore the present status of fluid therapy and clinical outcome in critically ill patients in intensive care units (ICU).ICU patients consecutively admitted to our ICU were prospectively enrolled.Patients' demographics,laboratory data,fluid record and clinical outcome were collected.Fluid intake quantity of all patients was at peak on the fifth day which was 2 806 (1 997,3 582)ml.From the fourth day in ICU,fluid balance started to benegative as-84 (-1 127,612)ml and gradually increased.Crystalloid solution was the main components.For treatment purposes,medication injections and nutrients were major fluids.Positive correlations were found between total fluid intake quantity,total crystalloid volume,total colloidal volume and hospital stay,ICU stay,duration of intubation (r values as 0.211,0.686,0.282,0.155,0.506,0.174,0.209,0.072,0.292,respectively P＜0.05).Moreover,positive correlations were also demonstrated between total colloidal volume and total bilirubin,direct bilirubin,alanine transaminase,aspartate transaminase,blood urea nitrogen,serum creatinine (r values as 0.196,0.242,0.190,0.335,0.284,0.223,respectively P＜0.05).

Objective To investigate the diagnostic value of neuron-specific enolase(NSE),central nervous system specific protein (S100β),interleukin-6 (IL-6) in sepsis-associated encephalopathy (SAE).Methods Clinical data of patients admitted to ICU and diagnosed with sepsis were collected from January 2015 to June 2016 in Xiangya Hospital,Central South University.SAE was defined as cerebral dysfunction in the presence of sepsis that also fulfilled the exclusion criteria.The acute physiology and chronic health score (APACHE Ⅱ),sequential organ failure assessment (SOFA),NSE,S100β,IL-6,ICU stay time and 28-day mortality were compared between the two groups.NSE,S1003 and IL-6 were measured on the 1 st and 3rd day in ICU to determine the optimal cut-off value of SAE.Results Among 59 enrolled patients,36 were assigned to SAE group while 23 were non-SAE group.The SAE group had a significantly higher APACHE Ⅱ and SOFA scores,as well as the length of ICU stay (P ＜ 0.01).The levels of NSE,S1003 and IL-6 in the two groups both increased on the 1st day,and decreased on the 3rd day.The level of NSE on the 1st day [19.28 (13.00,30.52) μg/L vs 16.61 (7.58,22.01 μg/L)] and the 3rd day[16.03 (9.40,21.29) μg/L vs 11.39(8.49,15.00) μg/L,P=0.029],IL-6 on the 1st day[676.25(81.34,5 000.00) mg/L vs [209.10(42.27,648.20) mg/L,P =0.005] and the 3rd day [157.10 (72.85,687.63) mg/L vs 55.92 (31.62,177.00) mg/L,P =0.026] of SAE group was significantly higher than those of non-SAE group.However S100β between groups on the 1st day [0.33(0.15,0.54) μg/L vs 0.23(0.16,0.53) μg/L] and the 3rd day[0.19(0.10,0.29) μg/L vs 0.10(0.05,0.17) μg/L] was neither significant (P ＞0.05).The diagnostic values for SAE of NSE,S1003 and IL-6 were 14.36 μg/L,0.14 μg/L and 91.305 mg/L with sensitivity 61.1％,61.1％,72.2％ and specificity 73.9％,69.6％,69.6％,respectively.The diagnostic AUC of NSE and IL-6 combination was 0.774,95％ CI 0.651-0.896.Conclusion All sepsis patients have different degrees of brain injury.NSE combined with IL-6 on the 3rd day in ICU demonstrates the diagnostic significance of SAE.