Objective To investigate the normal waveform,lantency and amplitude of auditory event-related potentials (ERPs) of exogenous components in children at different ages,and summarize the developmental rules and clinical perspectives of exogenous ERPs according to the International Federation of Clinical Neurophysiology (IFCN) Recommended Standards in 2009.Methods One hundred and thirty-six children aged from 3 to 17 years old (admitted in the departments from healthcare,orthopedics,general surgery,and respiratory and digestive diseases,and those recovered from respiratory infection and gastrointestinal infection),and healthy adults (from undergraduates of Chongqing medical university) were recruited in this study from 2008 to 2010.They were divided into 4 groups in accordance with their ages,that is,3 ～5,＞ 5 ～7,＞ 7 ～9,and ＞ 9 ～17 years old groups,and adult group (22 ～29 years old).ERPs were recorded from the midline site (Cz) with classical auditory Oddball paradigm.Each subject was tested twice or more to determine waveform repeatability.The overlapped graphs of ERPs under target and standard stimuli were obtained in the potentiometer.The exogenous ERPs,including P1,N1,P2 and N2,lantency and amplitude were measured.Results The latencies of exogenous ERPs under target and standard stimuli were shortened in a non-uniform manner with the increasing of age.No matter under target or standard stimuli,over 95％ of mean latencies of exogenous ERPs were within the range of 2SD.In addition to N1 component,the amplitude of P1,P2 and N2 components induced by target stimulus were in a trend of increased first and then decreased with the increasing of age.Compared with the children,the amplitude was much lower in the adults and adolescents (P ＜ 0.05).The N2 component induced by target stimulus was absent among 95％ healthy adults.The Standard deviations of amplitudes of exogenous components were great in all aged groups,indicating significant individual differences.Conclusion The latencies of exogenous ERPs are shortened with the increasing of age.Target stimulus will produce more stable results than the standard stimulus,and the ERPs under target stimulus can reflect the primary auditory cortex function of temporal lobe,and are independent on patients' cooperation.

Trypsin was purified from crude material of pig pancreas by AOT/isooctane reversed micellar system.The influence of the main operating parameters such as ethanol concentration in forward and backward extraction,pH,KCl and AOT concentration,temperature were investigated.Forward and backward extraction recovery of trypsin reached almost 90% and neared 100%,respectively.Finally,about 88% of total yield was obtained,and the specific activity of trypsin was increased to over 1800U/mg with purification factor of 5 folds more.In AOT-isooctane reverse micellar extraction system,denaturation or precipitation of proteins always occured due to strong electrostatic interaction between AOT-proteins molecules.It had been resolved by adding ethanol into reverse micellar system,and no denaturation was observed.Otherwise,the phase separation time was shortened significantly because of ethanol added.It was only 10 minutes or less to reach phases separation after forward and backward extraction.If this method can be applied in industry,efficiency will be greatly improved.

Adult ; Betacoronavirus ; Clinical Laboratory Techniques ; Coronavirus Infections ; diagnosis ; epidemiology ; etiology ; prevention & control ; therapy ; Diagnosis, Differential ; Extracorporeal Membrane Oxygenation ; Humans ; Pandemics ; prevention & control ; Pneumonia, Viral ; epidemiology ; etiology ; prevention & control ; therapy ; Practice Guidelines as Topic ; Respiration, Artificial

Objective To observe the curative effect of continuous airway positive pressure ventilation (CPAP) in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and cough syncope. Methods Forty-three hospitalized patients with OSAHS and cough syncope were collected in the Department of Respiration of Tianjin General Hospital, and analyzed the related information. They were given CPAP treatment, and were divided into good compliance group (n=26) and poor compliance group (n=17) according to CPAP compliance after a half-year treatment. The apnea hypoventilation index (AHI) and c-reactive protein (CRP) were compared before and after treatment between two groups. Results The positive correlation was found between the frequency of the cough syncope and indicators of OSAHS, such as AHI, body mass index (BMI), CRP, sleepiness score (ESS) and circumference of abdomen and neck (r=0.612, 0.431, 0.224, 0.654, 0.435 and 0.344,P<0.05). All these patients were cured after the treatment of both CPAP and medication for 1 or 2 weeks. During a half-year follow-up, the cough syncope didn’t occur in those patients of good compliance group, otherwise cough syncope still happened but with less frequency in patitents of poor compliance group. Before the treatment , there was no significant difference in AHI (45.00±15.69 vs. 48.70±16.47) and CRP (3.46± 1.15 vs. 3.38±0.72) between the two groups. After treatment, AHI (26.97±14.06 vs. 48.18±15.96) and CRP (1.56±0.76 vs. 3.18± 0.78) were significantly lower in the good compliance group than those of the poor compliance group (P<0.01). Conclusion Timely and sustained treatment of OSAHS may help reduce the incidence of cough syncope and significantly improve AHI, CRP and cough symptoms.

Aim To investigate the inhibitory effect of schizandrin B( SchB) on ultraviolet radiation b ( UVB) radiation-induced apoptosis of HaCaT cells. Methods Methyl thiazolyl tetrazolium ( MTT ) assay was used to examine the effect of SchB on cell viability recovery. Cell apoptosis and necrosis were measured by Ho-chest33342 staining. The p53, p21 and Caspase-3 mRNA expressions were examined by RT-PCR. Results In this study, we found that Sch B attenuated UVB-in-duced toxicity in HaCaT cells. Through Hoechst 33342 stain, we visualized that SchB could inhibit UVB-in-duced HaCaT cell death. The result demonstrated that p53 , p21 and Caspase-3 mRNA levels decreased com-pared with the control group. Conclusions Sch B at-tenuates the UVB-induced toxicity of HaCaT by inhibi-ting apoptotic gene expression. It plays a role in anti-photoaging.

Objective To measure the mRNA expression of immediate-early gene c-fos in endothelial cells by the use of different intermittent hypoxia (IH) protocols. Methods A gas control delivery system was homemade, which pro-duced IH/re-oxygenation(ROX) environmental exposure. The endothelial cells were exposed to IH/ROX cycles, and were di-vided into three groups (A, B and C). There were five sub-groups in each group. Group A included intermittent normoxia group, standard incubator control group, continuous hypoxia group (CH), 1.5%O2 IH group and 10%O2 IH group. There were different frequency IH of 1.5%O2 and 10%O2 sub-groups in group B and group C. Hypoxia time was 15 s. The intermittent hypoxia cycle was 60 and the ROX time was different. The total cycle time was different, including 1.5 h group, 3 h group, 5 h group, 6.5 h group and 9.5 h group. The mRNA expression of immediate-early gene c-fos was measured by real-time PCR. Results There was no significant difference in the level of c-fos mRNA between intermittent normoxia group and CH group. The expression of c-fos mRNA was significantly higher in 1.5%O2 IH group and 10%O2 IH group than that of intermit-tent normoxia group, and there was a higher expression level of c-fos mRNA in 1.5%O2 IH group than that of 10%O2 IH group (P＜0.01). It was found that the mRNA expression of c-fos increased gradually at first, and then gradually decreased. The expression of c-fos mRNA was significantly higher in 5 h group than that of other groups (P＜0.01). Conclusion The mRNA expression of immediate-early gene c-fos is increased after exposing to IH/ROX in endothelial cells, which is closely related with IH extents and frequencies.

Objective To investigate the effect of isoflurane preconditioning on the nuclear factor kappa B (NF-kB)activity of leukocytes in patients undergoing cardiac valve replacement with cardiopulmonary bypass (CPB).Methods Twenty ASAⅡorⅢpatients of both sexes aged 20-60 yrs undergoing cardiac valve replacement under CPB were randomly divided into 2 groups(n=10 each):control group(C)and isoflurane preconditioning group(I).Anesthesia was induced with midazolam 0.08-0.12 mg?kg~(-1),fentanyl 5-10?g?kg~(-1) and vecuronium 0.1 mg?kg~(-1).The patients were mechanically ventilated(FiO_2=100%)after tracheal intubation.Anesthesia was maintained with intermittent i.v.boluses of fentanyl and midazolam in group C or with 2 MAC isoflurane and intermittent i.v.boluses of fentanyl and midazolam in group I before CPB.Systolic BP was kept between 90-120 mm Hg,diastolic BP between 50-80 mm Hg and HR between 60-90 bpm in both groups. Isoflurane was discontinued at the initiation of CPB.Arterial blood samples were taken after tracheal intubation and before inhalation of isoflurane(T_0)at 30 min(T_1),1 h(T_2)and 2 h(T_3)after aortic unclamping for determination of NF-kB activity of leukocytes using electrophoretic mobility shift assay(EMSA).The amount of fentanyl,midazolam,dopamine and sodium nitroprusside(SNP)consumed during operation and the rate of recovery of spontaneous heart beat in both groups were recorded.Results The NF-kB activity was significantly increased after aortic unclamping in C group but there was no significant difference in NF-kB activity before CPB (T_0)and after aortic unclamping(T_(1-3))in I group.The NF-kB activity was significant lower at T_(1-3) in group I than in group C.The total amount of fentanyl consumed was 40-60?g?kg~(-1) in C group and 20-30?g?kg~(-1) in group I. Significantly less amount of dopamine was used in group I than in group C.There was no significant difference in SNP consumption between the 2 groups.The rate of recovery of spontaneous heart beat was significantly higher in group I than in group C(P＜0.01).The amount of dopamine consumed was positively correlated with the highest level of NF-kB activity in both group[r=0.962 in group C;r=0.908 in group I(P＜0.01)].Conclusion Isoflurane preconditioning can attenuate the NF-kB activity of leulocytes in patients undergoing cardiac valve replacement under CPB.

Objective To evaluate the effect of try psin on the proliferation,migration and adhesion of a skin squamous cell carcinoma cell line A431.Methods Cultured A431 cells were divided into several experimental groups treated with trypsin at concentrations of 0.1,1,10 and 100 nmol/L for 24,48 and 72 hours respectively,and a control group treated with DMEM complete medium only.Cell counting kit-8 (CCK8) assay was conducted to evaluate cellular proliferative activity to select the optimal concentration of trypsin.Then,some A431 cells treated with trypsin at the selected concentration for 24,48 and 72 hours respectively (or 48 hours only) served as the experimental groups (or group),and other A431 cells treated with DMEM complete medium served as the control group.Flow cytometry was performed to assess cell cycle distribution and proliferation index,fibronectin-based adhesion assay to estimate cell adhesive capacity,and wound healing assay and Transwell assay were conducted to evaluate the migratory capacity of cells in two-and three-dimensional space.Statistical analysis was carried out by using analysis of variance,paired samples t test and chi-square test.Results The proliferative activity of A431 cells increased along with the increase of trypsin concentrations,with the strongest increasing effect observed at 100 nmol/L.After treatment with 100 nmol/L trypsin,the experimental group showed a decrease in the percentage of G1-phase cells,but an increase in the percentage of S-phase cells,proliferation index,migratory and adhesive capacity compared with the control group (all P ＜ 0.05).Conclusion Trypsin can promote the proliferation,migration and adhesion of A431 cells.

Objective To investigate the effect of emphysema and intermittent hypoxia (IH) on the hepatic oxidative stress and inflammatory injury in rats. Methods Sixty male Wistar rats were randomly assigned to 4 groups, control group (A), emphysema group (B), IH group (C) and emphysema+IH group (D). Group A was normally fed. Group B was exposed to smoke, 30 min per time, twice everyday. Group C was exposed to 5%O2 30 s/Air 90 s for 8 h/d. Group D was exposed to smoke twice, about 30 min each time, and exposed 5%O2 30 s/Air 90 s for 8 h/d. After continues exposure for 8 weeks, five rats in each group were randomly selected for arterial blood gas analysis. The tissue blocks of liver was obtained for pathologi-cal scoring and measurements of liver oxidative stress in the rest 10 rats of each group. HE staining was used to calculate the mean lining interval (MLI) and mean alveolar number (MAN). The hepatic inflammatory factor interleukin-6 (IL-6), tumor necrosis factor-α(TNF-α), superoxide dismutase (SOD) activity, catalase (CAT) activity and malondialdehyde (MDA) con-centration were measured in four groups. Results Characteristics of emphysema were found in group B and group D. The values of MLI were significantly higher in Group B and group D than those of group A and group C (P<0.05). The values of MAN were significantly lower in group B and group D than those of group A and group C (P<0.05). The levels of SOD and CAT were significantly lower in group B, group C and group D than those of group A (P<0.05). And the levels of SOD and CAT were significantly lower in group D than those of group B and group C (P<0.05). The values of liver MDA were signifi-cantly higher in group B, group C and group D than those of group A, and the values were significantly higher in group D than those of group B and group C (P<0.05). The liver histological scores and the levels of IL-6 and TNF-αwere signifi-cantly higher in group B, group C and group D than those of group A, and the values were significantly higher in group D than those of group B and group C (P<0.05). Conclusion Emphysema and IH have synergistic action in causing hepatic oxidative stress and inflammation.

Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for atherosclerosis. Accumulated evidence has revealed that OSAS can induce systemic inflammation, oxidative stress, and endothelial dysfunction, which will contribute to the pathogenesis of atherosclerosis. T lymphocytes can be activated by inflammation and oxidative stress, resulting in the elevated cytotoxicity towards vascular endothelial cells. Thus, T lymphocytes play a key role in OSAS-related atherosclerosis development or progression via immuno-inflammatory alterations. This review described the current development of the role of T lymphocytes in OSAS-related atherosclerosis.