Objective To generate the spaO-ompA fusion gene of Salmonella paratyphi A and its prokaryotic expression system,and to determine the immunoprotection of the recombinant expression product rSpaO-OmpA.Methods A flexible peptide sequence was used to link spaO and ompA genes and a prokaryotic expression system of spaO-ompA fusion gene was subsequently generated.SDS-PAGE and Bio-Rad Agarose Image Analyzer were applied to examine the expression as well as the yield of the target recombinant protein rSpaO-OmpA.The antigenicity and immunoreactivity of rSpaO-OmpA were determined using immunodiffusion test,Western Blot assay and micro-Widal's test.By a mouse infection model,the immunoprotection of rSpaO-OmpA against the lethal challenge of S.paratyphi A was determined.In the animal protective test,the recombinant expressed SpaO (rSpaO) and OmpA ( rOmpA ) were used as the controls.Results The generated spaO-ompA fusion gene had 100％ nucleotide and amino acid sequence identities compared to the single spaO or ompA gene.The constructed prokaryotic expression system IPTG E.coli BL21DE3pET42a-spaO-ompA expressed the recombinant protein rSpaO-OmpA.rSpaO-OmpA combined with the antiserum against wholecell of S.paratyphi A to present positive hybridization signal and induced specific antibody in the immunized rabbits.Immunization with 100 or 200 μg rSpaO-OmpA contributed 66.7％ (8/12) or 83.3％ (10/12) immunoprotective rates in mice when the animals were attacked with S.paratyphi A.The immunoprotective rates produced by rSpaO-OmpA were significantly higher than that of equal rSpaO or rOmpA( P＜0.05 ).The sera from rSpaO-OmpA immunized mice presented 1∶5-1∶40 agglutination titers to the H antigens of different S.paratyphi species,and 1∶1-1∶16 immunodiffusion titers to rSpaO,rOmpA and rSpaO-OmpA proteins,respectively.Conclusion The artificially fusion antigen,rSpaO-OmpA,has more powerful immunogenicity and immunoprotection that the equal rSpaO or rOmpA.

Objective To observe the onset of vascular smooth muscle cell (VSMC) senescence induced by tert-butyl hydroperoxide (t-BHP) and the intervention effect of dehydroepiandrosterone (DHEA). Methods The VSMCs were divided into four groups: blank control group, t-BHP group (incubated with 80 μmol/L t-BHP for 72 h), 10 nmol/L DHEA intervention group (pretreated with 10 nmol/L DHEA 30 min before t-BHP) and 100 nmol/L DHEA intervention group (pretreated with 100nmol/L DHEA 30 min before t-BHP). Two ageing markers of ageing associated β-galactosidase activity and cell proliferation activity were adopted as main indexes. β-galactosidase activity was measured with immunocytochemical method and cell proliferation activity was measured with flowcytometry. Results After continuous treatment with 80 mmol/L t-BHP for 72 h, the ratios of G0/G1 phase cells and SA-β-galactosidase staining positive cells increased as compared with blank controlgroup [(89.4±3.4)% vs. (49.5±5.5)%, (3.5±1.2)% vs. (75.3±4.3)%], which indicated that VSMCs senescence were successfully induced by t-BHP. While the above changes were smaller in 100 nmol/L DHEA intervention group than in t-BHP group. Conclusions With ageing,accumulation of damage produced by reactive oxygen species may be an important mechanism causing the onset of VSMCs senescence. DHEA may be able to retard the progression of VSMCs senescence through antioxidant effect.

Objective To explore the mechanism of the catdioprotection of isoflurane delayed preconditioning on myocardial ischemia reperfusion injury in rabbits.Method Thirty male New Zealand white rabbits,weighing 2.0 to 2.5 kg,were randomly divided into three groups(ten for each group):Control group(group C),I/R group(I/R group) ,2.0% isoflurane group(group S) .Group S was exposed to 2.0% isoflurane-100% oxygen for2 h.Group C and I/R group were exposed 2 h to 100% oxygen served as untreated controls.Twenty-four hours later I/R group and group S underwent 40 rain of coronary occlusion followed by 2 h of reperfusion.Blood samples were taken from arterial line at 20 min before occlusion(T1) ,20 rain after occlusion(T2) ,40 rain after occlusion(T3) ,1 h after reperfusion(T4) and 2 h after reperfusion(TS) for determination of plasma IL-10 levels and TNF-alevels by ELISA.At the end of the reperfusion,infarct size and area at risk were defined by Evans and TTC staining.The heart was harvested and levels of the nuclear factor kappa β(NF-κB)activity were determined by Western Blot,and ultrastructures were observed by electron microscopy.The data was expressed as,and were analyzed by using oneway ANOVA test with SPSS 13.0.P value less than 0.05 indicated statistical significance.Results The NF-κB activity of group S was significantly lower than that of group I/R(P<0.05).Group S significantly(P<0.05)reduced infarct size(19.7%±2.8% in group S) of the left ventricular area at risk as compared with control (37.8 %±1.7 % in I/R group).The injury of I/R group was worse than that of group S from the changes of the cellular structure under light microscope.Group S had a lower levels of TNF-α and also had a higher level of IL-10.Conclusions Isoflurane can inhibit NF-κB activity during myocardial ischemia reperfusion and modulate the cytokine expression,which may be one of molecular mechanisms of Isoflurane delayed preconditioning on cardioprotection.

OBJECTIVE: To explore the effect of isoflurane preconditioning on the plasma concentration of matrix metalloproteinase (MMP)-9 and myocardial ultramicrostructure in patients undergoing cardiac valve replacement. METHODS: Thirty patients undergoing elective cardiac valve replacement with cardiopulmonary bypass (CPB) were randomly assigned to a control group (ný15) and an isoflurane group (ný15). In the isoflurane group, isoflurane of 1.0 minimum alveolar concentration end-tidal( 1.1% approximately 1.2%) was administered for 30 min followed by a 15 min washout period before the CPB. The control group did not inhale isofurane, and there was no difference in the other drugs in the 2 groups. Blood samples for MMP-9 were obtained before incision(T(0)) and at 30 min (T(1)),6 h (T(2)),12 h (T(3)), and 24 h (T(4)) after the reperfusion. Right atrial biopsies were collected before and after the CPB to observe the myocardial ultramicrostructure. RESULTS: Compared with T(0), the mean MMP-9 level significantly increased at T(1), T(2) and T(3) in the control group(P<0.01), while the MMP-9 level only at T(1) significantly increased in the isoflurane group (P<0.01). The mean MMP-9 level was significantly reduced in the isoflurane group at T(2) compared with each time point in the control group. The difference in MMP-9 levels between T(1), T(2), T(3) and T(0) was significantly lower in the isoflurane group than that in the control group (P<0.01). The ultramicrostructure injury of myocardium under electron microscope in the control group was worse than that in the isoflurane group. CONCLUSION The plasma concentration of MMP-9 is inhibited by isoflurane preconditioning in patients undergoing cardiac valve replacement after CPB, which might be part of its protective mechanism against myocardium injury after CPB.
Adolescent ; Adult ; Cardiopulmonary Bypass ; Cardiotonic Agents ; therapeutic use ; Female ; Heart Valve Prosthesis Implantation ; methods ; Humans ; Ischemic Preconditioning, Myocardial ; methods ; Isoflurane ; therapeutic use ; Male ; Matrix Metalloproteinase 9 ; blood ; Middle Aged ; Myocardium ; ultrastructure ; Young Adult

OBJECTIVETo investigate the impact of long-time and short-time blood pressure variability (BPV) on glomerular filtration rate (eGFR) in elderly population.

METHODSA total of 2 464 participants aged of ≥60 years old without history of stroke and coronary heart disease were selected with random sampling method from the individuals underwent health check up in Tangshan Kailuan Hospital, Kailuan Linxi Hospital, Kailuan Zhaogezhuang Hospital between 2006 and 2013. The study participants were asked to join a face-to-face interview every two years. Long-time BPV was defined as the standard deviation of all SBP values at the baseline visit and following visits, short-time BPV was defined as the standard deviation of day time blood pressure and night time blood pressure which was derived from 24 hours ambulatory blood pressure monitoring. Multivariate linear regression models were used to test the impact of long- and short-time BPV on eGFR.

RESULTSThe study included 3 participants groups including the long-time SBPV group (2 279 participants), the short-time SBPV group (1 636 participants) and the long- plus short-time SBPV group (1 632 participants). Participants were further sub grouped by median value (NO.1median value). eGFR in the long-time SBPV NO.1 and NO.2 group was 83.19 and 81.49 ml·min(-1)·1.73 m(-2) respectively, in the short time SBPV NO.1 and NO.2 group was 83.53 and 80.81ml·min(-1)·1.73 m(-2) of the day time, and was 83.20 and 81.14 ml·min(-1)·1.73 m(-2) of the night time, respectively. eGFR in the long- plus short-time SBPV NO.1 and NO.2 group was 83.21 and 81.08 ml·min(-1)·1.73 m(-2) of the long-time SBPV, and was 83.53 and 80.75 ml·min(-1)·1.73 m(-2) of the day time, and was 83.18 and 81.11 ml·min(-1)·1.73 m(-2) of the night time. Significant linear relationship was found between higher day time SBPV and lower eGFR (P<0.05). After adjusting for confounding parameters including age, sex, body mass index, 1 mmHg(1 mmHg=0.133 kPa) of day time SBPV increase was related 0.21 ml·min(-1)·1.73 m(-2) eGFR decrease (P<0.05).

CONCLUSIONThe higher day time SBPV is associated with reduced eGFR in the elderly population.Clinical Trail Registry Chinese Clinical Trial Registry, ChiCTR-TNC-11001489.

Aged ; Blood Pressure ; Blood Pressure Monitoring, Ambulatory ; Coronary Disease ; Glomerular Filtration Rate ; Humans ; Time Factors

Objective To assess the prognosis and effect on renal function of pediatric urolithiasis caused by melamine-contaminated milk powder (PUMMP) in a long-term follow-up.Methods One hundred and two of 8335 children (≤ 6-year-old) with history of consuming melamine-contaminated milk powder screened in our hospital were followed up for eighteen months after diagnosis. Urinary system ultrasonography, urinalysis, urinary microprotein profiles [microalbumin (ALBU), immunoglobulin G (IgG), and N-acetyl-β-D-glucosidase (NAG)], urinary melamine and cyanuric acid were examined in the first visit and at the end of follow-up. Results Follow-up was completed in 91 children and the stone was excreted in 82 children (90.1%).Stones less than 5 mm in diameter were most vulnerable to discharge, and stones larger than 10 mm could not be expelled without interventions. At the end of follow-up, no melamine or cyanuric acid was found in the urine samples of 74 patients. Urinalysis showed that incidences of proteinuria, microscopic hematuria and leukocyturia were 0%, 5.1% and 2.0%, which were significant different from those in the first visit (Pproteinutria=0.123, Phemnatuna=0.038 and Pleukocyhuris=0.005).Urinary microprotein profiles revealed that some children whose urinalysis was normal still presented glomerular and renal tubular injury and the abnormal rates were 8.8% and 12.1%respectively. The glomerular injury was mainly related to persistent stone, male and younger.Conclusions 90.1% of children with PUMMP passes urinary stones at the end of follow-up.Stone size is the major risk factor of discharge. No melamine or cyanuric acid is found in the urine of children. After eighteen months, glomerular and renal tubular injury is still found in some patients. Further follow-up is necessary.