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@#Objective To explore the risk factors and predictive value of acute kidney injury (AKI) after total aortic arch replacement. Methods The clinical data of patients undergoing total aortic arch replacement in our hospital from January 2018 to June 2019 were retrospectively analyzed, and patients receiving preoperative renal replacement therapy and missing creatinine values were excluded. According to whether postoperative AKI occurred, patients were divided into an AKI group and a control group. The univariate and multivariate analyses (logistic regression) were used to explore the independent risk factors of AKI. The receiver operating characteristic curve was used to analyze the significant factors in predicting the occurrence of AKI after total aortic arch replacement. Results A total of 162 patients were included in the study, including 135 (83.3%) males and 27 (16.7%) females, with an average age of 52.61±9.90 years (range: 22 to 73 years). The incidence of AKI was 68.5% (n=111). The results of univariate and multivariate analyses showed that the postoperative serum cystatin C level (OR=76.145, 95%CI 15.575-372.260, P<0.01) was an independent risk factor for AKI after total aortic arch replacement. When its cut-off value was above 1.08 mg/L, the specificity for predicting postoperative AKI was 70.59%, and the sensitivity was 85.59%. Conclusion The postoperative cystatin C level is an independent risk factor for AKI after total aortic arch replacement and has predictive value.
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Objective:To investigate the effects of sodium butyrate (NaB) on long-term anxiety like behavior and inflammatory activation of microglia in the hippocampus of sepsis-associated encephalopathy (SAE) mice.Methods:① Animal experiment: fifty C57BL/6 mice aged 6-8 weeks were randomly divided into Sham group (only the cecum was found by laparotomy without perforation or ligation), and SAE model group caused by cecal ligation and puncture (CLP; SAE model group, the cecum was found by laparotomy and perforated after ligation. The open field test indicated that the ability of independent exploration decreased and showed anxiety like behavior, which proved that the SAE model was successfully replicated) and NaB pretreatment group was established (NaB was administered at a dose of 500 mg·kg -1·d -1 for 3 days before modeling, and the same dose once a day for 3 days after modeling). Open field test was used to detect the anxiety like behavior of mice at 7 days. The protein expressions and content changes of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in hippocampus of mice at 1 day and 3 days after operation were detected by Western blotting and enzyme linked immunosorbent assay (ELISA). Immunofluorescence staining was used to observe microglia labeled protein ionized calcium bindingadaptor molecule-1 (Iba-1) and TNF-α protein co localization. ② Cell experiment: mouse microglia cell line BV-2 microglia were divided into blank control group, lipopolysaccharide (LPS) group (cells were treated with 1 mg/L LPS), and NaB treatment group (cells were treated with 1 mg/L LPS+5 mmol/L NaB). The protein expressions of IL-1β, TNF-α, Toll-like receptor 4 (TLR4), phosphorylated nuclear factor-κB p65 (p-NF-κB p65), nuclear factor-κB p65 (NF-κB p65) and NF-κB inhibitor protein-α (IκB-α) were detected by Western blotting. The expressions of Iba-1 and TNF-α in each group were observed by immunofluorescence. Results:① Animal experiment: compared with the Sham group, the distance and duration of movement in the central area, the total distance moved of mice decreased 7 days after the establishment of SAE model group were decreased [distance of movement in the central area (mm): 13.45±3.97 vs. 161.44±27.00, duration of movement in the central area (s): 1.82±0.58 vs. 13.45±2.17, the total distance moved (mm): 835.01±669.67 vs. 2 254.51±213.45, all P < 0.05]. In the hippocampus tissues of mice, a large number of nerve nuclei were pyknotic and deeply stained, and the arrangement of nerve cells was disordered. The cell bodies of microglia in mouse hippocampus increased significantly. The number of positive cells of Iba-1/TNF-α (Iba-1 +/TNF-α +) increased significantly. The contents and protein expression of proinflammatory factors TNF-α, IL-1β in hippocampal homogenate supernatant 3 days after operation in SAE model group were significantly higher than those in Sham group [TNF-α (ng/L): 119.17±18.40 vs. 90.18±21.17, IL-1β (ng/L): 407.89±70.64 vs. 313.69±34.63; TNF-α/GAPDH: 1.42±0.50 vs. 0.80±0.08, IL-1β/GAPDH: 1.27±0.22 vs. 0.85±0.25, all P < 0.05]. After intragastric administration of NaB, the distance and duration of movement in the central area of mice were significantly higher than those in SAE model group [distance of movement in the central area (mm): 47.39±15.63 vs. 13.45±3.97, duration of movement in the central area (s): 6.12±1.87 vs. 1.82±0.58, all P < 0.05]. There was no significant change in the total distance moved (mm: 1 550.59±1 004.10 vs. 835.01±669.67, P > 0.05). The pyknosis and deep staining of nerve nuclei in mice were significantly less than those in SAE model group. The number of Iba-1 +/TNF-α + positive cells decreased significantly. The contents and protein expression levels of proinflammatory factors TNF-α, IL-1β in hippocampal homogenate supernatant 3 days after operation were significantly lower than those in SAE model group [TNF-α (ng/L): 64.95±9.10 vs. 119.17±18.40, IL-1β (ng/L): 311.94±69.92 vs. 407.89±70.64; TNF-α/GAPDH: 1.02±0.36 vs. 1.42±0.50, IL-1β/GAPDH: 0.86±0.20 vs. 1.27±0.22, all P < 0.05]. ② Cell experiment: after LPS intervention, the fluorescence intensity of TNF-α in BV-2 cells was significantly enhanced, the protein expression levels of TNF-α, IL-1β, TLR4 and p-NF-κB p65 protein increased (TNF-α/GAPDH: 0.39±0.06 vs. 0.20±0.02, IL-1β/GAPDH: 0.27±0.03 vs. 0.19±0.01, TLR4/GAPDH: 0.55±0.12 vs. 0.33±0.09, p-NF-κB p65/NF-κB p65: 0.55±0.05 vs. 0.29±0.04, all P < 0.05), the expression level of IκB-α was lower than that in the control group(IκB-α/GAPDH: 0.54±0.06 vs. 0.81±0.03, P < 0.05). After NaB treatment, the fluorescence intensity of TNF-α in BV-2 cells was decreased. The protein expression levels of TNF-α, IL-1β, TLR4 and p-NF-κB p65 protein were significantly lower than that of LPS model group (TNF-α/GAPDH: 0.26±0.02 vs. 0.39±0.06, IL-1β/GAPDH: 0.11±0.04 vs. 0.27±0.03, TLR4/GAPDH: 0.28±0.14 vs. 0.55±0.12, p-NF-κB p65/NF-κB p65: 0.29±0.01 vs. 0.55±0.05, all P < 0.05), the protein expression level of IκB-α was significantly higher than that in the LPS group (IκB-α/GAPDH: 0.75±0.01 vs. 0.54±0.06, P < 0.05). Conclusion:NaB could antagonism the TLR4 activation induced by LPS, thus inhibiting p-NF-κB p65 nuclear transcription and IκB-α degradation. It can reduce microglia activation and secretion of inflammatory factors, and finally improve the inflammation in the hippocampus of septic mice and long-term anxiety like behavior.
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Objective:To explore the effect of post-pyloric feeding by spiral nasoenteric tubes on the prognosis of critically ill patients with acute gastrointestinal injury (AGI) grade Ⅱ.Methods:A retrospective study was performed to analyze the clinical data of critically ill adult patients with AGI grade Ⅱ, who were enrolled in three randomized controlled trials conducted by Guangdong Provincial People's Hospital for post-pyloric tube placement between April 2012 and May 2019. Data including demographic characteristics, serological indicators of nutrition, the tube tip position confirmed by abdominal X-ray 24 h after tube insertion, and intensive care unit (ICU), 28-day and hospital mortality were collected. Patients were divided into the post-pyloric feeding group and gastric feeding group according to the tube tip position. Propensity score matching method was used to perform 1:1 matching, and the differences of each index between the two groups were compared after matching. Then the influencing factors of P<0.1 were included in multivariate logistic regression analysis to investigate the potential ICU mortality risk factors of critically ill patients with AGI gradeⅡ. Factors with 0.1 level of significance from the univariate analysis were considered in the multivariate analysis. Results:There were 90 patients in post-pyloric feeding group and 90 patients in the gastric feeding group. Demographics and clinical characteristics of study population were well balanced between the two groups after matching. ICU, 28-day and hospital mortality in the post-pyloric feeding group were significantly lower than those in the gastric feeding group (4.4% vs 15.6%, 14.4% vs 27.8%, 6.7% vs 17.8%, all P < 0.05). Multivariate logistic regression analysis indicated that post-pyloric feeding was an independent protective factor [odds ratio ( OR)=0.295, 95% confidence internal (95% CI): 0.091-0.959, P=0.042] and APACHEⅡ score was an independent risk factor ( OR=1.111, 95% CI: 1.025-1.203, P=0.010) for ICU mortality of critically ill patients with AGI gradeⅡ. Conclusions:Post-pyloric feeding for critically ill patients with AGI grade Ⅱ could decrease ICU mortality and is an independent protective factor against mortality.
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To explore the effect of post-pyloric feeding by spiral nasoenteric tubes on ventilator-associated pneumonia (VAP) in neurocritical care patients. Methods A retrospective study was performed to analyze the clinical data of 175 neurocritical care adult patients with mechanical ventilation (MV) more than 48 hours, who were enrolled in three randomized controlled trials (RCT) conducted by Guangdong Provincial People's Hospital for post-pyloric tube placement between April 2012 to March 2019. The following patient clinical data were collected when patients were enrolled: gender, age, neurologic diagnosis, comorbidities, medication, endotracheal reintubation, bronchoscope treatment, the distal site of nasoenteric tubes, and acute physiology and chronic health evaluation Ⅱ(APACHEⅡ) score, sequential organ failure assessment (SOFA) score, Glasgow coma scale (GCS) score, and acute gastrointestinal injury (AGI) grade assessed. Patients were divided into VAP group and non-VAP group according to the occurrence of VAP, and the differences of each index between the two groups were compared. Then the influencing factors of P < 0.1 were included in multivariate Logistic regression analysis to identify the potential risk factors affecting the incidence of VAP. Furthermore, patients were divided into gastric feeding group and post-pyloric feeding group according to the distal site of nasoenteric tubes, and subgroup analysis was performed to evaluate the variety of VAP in patients with different tube sites and status. Results ① Forty-two patients occurred VAP in 175 MV patients, and the incidence of VAP was 24.0%. ② Univariate analysis showed the P value of post-pyloric feeding, APACHE Ⅱscore, GCS score and bronchoscope treatment were less than 0.1, and post-pyloric feeding and GCS score in VAP group were significantly lower than those in non-VAP group [post-pyloric feeding: 19.0% (8/42) vs. 36.8% (49/133), GCS:5 (3, 7) vs. 6 (4, 9), both P < 0.05]. Multivariate Logistic regression analysis indicated that post-pyloric feeding was independent protective factor [odds ratio (OR) = 0.360, 95% confidence internal (95%CI) = 0.151-0.857, P = 0.021] and bronchoscope treatment was the independent risk factor (OR = 2.210, 95%CI = 1.051-4.647, P = 0.036) for VAP. ③ The incidence of VAP was 28.8% (34/118), 0% (0/4), 8.3% (1/12), 26.7% (4/15), 22.2% (2/9) and 5.9% (1/17) respectively when tube tip in stomach, D1, D2, D3, D4 and jejunum confirmed by abdominal radiography. Post-pyloric feeding in each proportion seemed to present lower VAP rate compared with gastric feeding, however, no significant difference was found (all P > 0.05). ④ The incidence of VAP in post-pyloric feeding group was significantly lower than that in gastric feeding group [14.0% (8/57) vs. 28.8% (34/118), OR = 0.403, 95%CI = 0.173-0.941, P = 0.032]. Lower VAP rate appeared on patients with SOFA < 12 (OR = 0.392, 95%CI = 0.154-0.995, P = 0.044) and AGI grade ≥Ⅱ (OR =0.086, 95%CI = 0.011-0.705, P = 0.006) fed by post-pyloric route according to the result of subgroup analysis stratified by age, gender, APACHEⅡ score, SOFA score and AGI grade. Conclusion Post-pyloric feeding would decrease the incidence of VAP in neurocritical care patients on MV.
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Objective To identify the risk factors of ventilator-associated pneumonia (VAP) in infants after surgical correction for tetralogy of Fallot (TOF).Methods This study performed at Guangdong general hospital in China,130 infants (less than 12 months,mechanical ventilation time≥48 h) undergoing surgical correction for TOF were included between January 2013 and December 2017.Ventilator-associated pneumonia was defined according to the CDC/NHSN definitions guidelines issued in 2008.T test or Wilcoxon rank sum test was used in univariate analysis,and the variables with P ＜ 0.05 in the univariate analysis were added to a multiple logistic regression to identify the risk factors of VAP in infants after surgical correction for Tetralogy of Fallot.The area under the receiver operating characteristic (ROC) curve was calculated as a measure of accuracy.Results A total of 130 infants were included,however,VAP was found in 34 (26.2％) infants.The single variables significantly associated with a risk of VAP were:pre-operative hypoxic,pre-operative pneumonia,pre-operative mechanical ventilation support,prolonged cardiopulmonary bypass time,reintubation,pulmonary atelectasis,pleural effusion hydrothorax,prolonged mechanical ventilation support time,low cardiac output and transfusion of erythrocyte concentrate or fresh frozen plasma.Multiple logistic regression analysis showed prolonged cardiopulmonary bypass time (OR =1.02),reintubation (OR =16.111),pulmonary atelectasis (OR =8.133),low cardiac output (OR =7.649) and prolonged mechanical ventilation support time (OR =1.014) were independent risk factors for VAP in infants after TOF surgical correction.The area under the curve demonstrates the accuracy of the model.Conclusion The occurrence rate of VAP was high and risk factors for VAP after TOF surgical correction were complex.These results can be used to prevent and reduce the occurrence of VAP.
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Objective To investigate the effects of stress hyperglycemia on prognosis in patients with severe cerebral vascular diseases.Methods A retrospective analysis was conducted.416 patients with severe cerebral vascular diseases confirmed by radiological imaging admitted to intensive care unit (ICU) of Guangdong General Hospital from December 2013 to June 2015 were enrolled.According to the values of randomise blood glucose (RBG) and glycosylated hemoglobin (HbA1c) and diabetes history,the patients were divided into euglycemia group (RBG ＜ 11.1 mmol/L,HbA1c ＜ 0.065,without diabetes history),diabetes group (RBG ≥ 11.1 mmol/L,HbA1c ≥ 0.065,with diabetes history),and stress hyperglycemia group (RBG ≥ 11.1 mmol/L,HbA1c ＜ 0.065,without diabetes history).The nosocomial infection rate,the length of ICU stay and 28-day mortality were compared among the three groups.Survival analysis was performed using Kaplan-Meier method,and multivariate Cox proportional hazard model was used to estimate the risk of death.Results Among 416 patients,there were 40 cases with stress hyperglycemia,46 with diabetes and 330 with euglycemia,with the incidence of stress hyperglycemia of 10.81％ (40/370).The nosocomial infection rates in the stress hyperglycemia group and diabetes group were significantly higher than those of the euglycemia group [55.00％ (22/40),52.17％ (24/46) vs.18.79％ (62/330),both P ＜ 0.01],and the length of ICU stay was significantly longer than that of the euglycemia group (days:16.53 ± 6.26,15.79 ± 8.51 vs.9.23 ± 4.29,both P ＜ 0.01).No significant differences in nosocomial intection rate and length of ICU stay were found between stress hyperglycemia group and diabetes group (both P ＞ 0.05).The 28-day mortality rate in stress hyperglycemia group was significantly higher than that of diabetes group and euglycemia group [47.50％ (19/40) vs.26.09％ (12/46),10.30％ (34/330),P ＜ 0.05 and P ＜ 0.01].It was showed by Kaplan-Meier survival analysis that 28-day cumulative survival rate in stress hyperglycemia group was significantly lower than that of euglycemia group and diabetes group (log-rank =6.148,P =0.043).It was showed by Cox death risk analysis that stress hyperglycemia was the risk factor of death in patients with severe cerebral vascular disease [hazard ratio (HR) =1.53,95％ confidence interval (95％CI) =1.04-1.26,P =0.001].Conclusion The patients with stress hyperglycemia may have a higher 28-day mortality and a poorer prognosis compared with those with diabetes and normal blood glucose in severe cerebral vascular diseases.
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[ ABSTRACT] AIM:To explore whether IL-1βinhibits the oligodendrocyte precursor cell ( OPCs) differentiation and affects axonal myelination.METHODS:One-day-old SD rats were randomly divided into control group and LPS group ( 48 rats in each group) .The rats in LPS group were intraperitoneally injected with 1 mg/kg LPS.The rats in control group were injected with an equal volume of PBS.The rats in each group were further divided into 3 h, 24 h, 3 d, 7 d, 14 d and 28 d subgroups after injection.The expression of IL-1βand IL-1R1 in the rat corpus callosum at 3 h, 24 h, 3 d, 7 d was determined by double immunofluorescence and Western blotting.The myelin basic protein( MBP) expression in the rat cor-pus callosum at 14 d, 28 d after injection was also measured.In vitro, primary OPCs culture was performed and divided in-to control group, 30 μg/L IL-1βgroup, 30 μg/L IL-1β+IL-1Ra group and 30 μg/L IL-1Ra group.The expression of MBP in the OPCs induced differentiation for 3 d was observed by double immunofluorescence and Western blotting.RE-SULTS:The expression of IL-1βand IL-1R1 in the rat corpus callosum at 3 h, 24 h, 3 d, 7 d after LPS injection was ob-viously increased and the expression of MBP in the rat corpus callosum at 14 d, 28 d in LPS group was obviously decreased compared with control group in vivo.The level of MBP was significantly decreased after IL-1βtreatment for 3 d in vitro. However, IL-1Ra (IL-1R inhibitor) reversed the down-regulation of MBP expression.IL-1βinhibited the expression of p-ERK, ERK over-expression reversed the down-regulation of MBP expression compared with IL-1βgroup.CONCLUSION:IL-1βinhibits the differentiation of OPCs, which may be involved in ERK pathways, thus leading to axonal hypomyelination in the corpus callosum of septic neonatal rats.
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Objective To investigate the clinical value of the ratio of plasma vascular endothelial growth factor level to platelet count (VEGF/PLT) in predicting 28-day prognosis in patients with sepsis.Methods A prospective cohort study was conducted.From September 2009 to March 2013,164 sepsis patients in Intensive Care Unit (ICU) of Guangdong General Hospital were included for study.Patients with age younger than 18 years old,the illness already reaching final stage of chronic diseases,suffering from two or more organs dysfunction within 3 days,acute pancreatitis without infection,or less than 28 days of expected survival time were excluded.Finally,135 patients were included in the further analysis.Peripheral blood samples were collected at admission.Routine blood tests were done,and then VEGF levels in plasma were measured by enzyme linked immunosorbent assay (ELISA).Acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) scores were recorded every day for 7 days.Patients' prognosis was assessed during the following 28 days.The patients were divided into 28-day survival group and non-survival group.Comparison between two groups was done by single factor analysis.Spearman rank correlation was used to analyze the correlation between VEGF levels and PLT.Mutivariate logistic regression analysis was performed to identify the independent risk factor for 28-day prognosis.Receiver operating characteristic curve (ROC curve) was plotted,and the effect of related indexes on predicting 28-day survival was evaluated by area under ROC curve (AUC).Results There were no significant differences in VEGF (ng/L:471.73 ± 198.34 vs.383.49 ± 266.54,t=-1.918,P=0.057),PLT (× 109/L:220.40±127.60 vs.246.42± 100.72,t=1.275,P=0.204),leucocyte counts (× 109/L:12.48 ±4.62 vs.13.70 ±5.97,t=1.063,P=0.292),mean arterial pressure [mmHg (1 mmHg=0.133 kPa):86.50 ± 12.04 vs.91.03 t 13.10,t=1.557,P=0.123] and blood lactic acid (mmol/L:1.79 ± 1.30 vs.1.50 ± 0.60,t=-1.768,P=0.079) at admission between the non-survival group (n=42) and survival group (n=93).VEGF/PLT (2.59 ± 1.44 vs.1.73 ± 1.13,t=-3.756,P=0.000) as well as APACHE Ⅱ scores (15.50 ± 4.50 vs.13.28 ± 4.61,t =-2.022,P=0.045) of the non-survival group were significantly higher than those of survival group,and oxygenation index (PaO2/FiO2) of the non-survival group was significantly lower than that of survival group (kPa:32.38 ± 11.12 vs.37.04 ± 10.97,t=2.278,P=0.024).Correlation analysis showed that the concentration of VEGF was positively correlated with PLT (r=0.271,P=0.001).It was shown by multivariate logistic regression analysis that only VEGF/PLT was the independent risk factor in predicting 28-day prognosis in patients with sepsis [odds ratio (OR) was 1.591,95％ confidence interval (95％CI) 1.164-2.175,P=0.004].AUC of VEGF/PLT was 0.704 ± 0.047 (P=0.000,95％CI:0.611-0.797) for predicting 28-day survival.The optimal cut-off point was 1.32,and the sensitivity and specificity were 81.0％ and 48.4％,respectively.Conclusion VEGF/PLT can be used as one of the indicators to predict 28-day survival in patients with sepsis.
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Objective To analyze the potential factors facilitating post-pyloric placement of spiral naso-jejunum tube in critically ill patients.Methods A retrospective study was carried out in patients requiring enteral nutrition (EN) from Apr 2005 through Dec 2011 in Intensive Care Unit (ICU).Severity of illness was assessed with APACHE Ⅱ score (acute physiology and chronic health evaluation Ⅱ).A selfpropelled spiral naso-jejunum tube was placed and observed for 24 hours.The forward movement and place of the tube tip was checked by bedside X-ray.The APACHE Ⅱ score,therapeutic measures,agents administered within 24 hours after tube insertion were recorded.The patients were divided into the success group and the failure group identified by bedside X-ray whether the tube tip entered into jejunum or not.Univariate analysis and multivariate Logistic regression analysis were used to find out the potential factors impacting on the success or failure in post-pyloric placement of naso-jejunum tube.Results A total of 508 patients composed of 337 male and 171 female,and aged (62.0 ± 19.2) years with APACHE Ⅱ score of (21.9 ± 7.3) were enrolled for study.The placement was successful in 205 (40.4％) of 508 patients.Univariate analysis showed that APACHE Ⅱ score ≥ 20,sedatives and analgesics,catecholamines,prokinetics,artificial airway and mechanical ventilation were potential factors facilitating the post-pyloric placement of naso-jejunum tube.Multivariate logistic regression identified that APACHE Ⅱ score ≥ 20,sedatives and analgesics and prokinetics were independent factors facilitating the post-pyloric placement of naso-jejunum tube.Conclusions The success rate of self-propelled spiral nasojejunal tubes insertion was relatively low.The prokinetics contributed higher success rate of naso-jejunum tube placement than factors of APACHE Ⅱ score ≥ 20,sedative and analgesic,catecholamine drugs,artificial airway and mechanical ventilation.There were no effects of age and gender on the placement of naso-jejunum tube.
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Objective To investigate the characteristic changes in cerebral infarction and brain edema. Method A total of 122 Healthy adult male Spraque-Dawley rats were randomly (random number) divided into three groups: normal group ( n = 12), sham operated group (n=12) and cerebral ischemia group ( n = 98). Cerebral infarction and brain edema were induced by a permanent occlusion of right middle cerebral artery (POM-CA) with ligature. According to the duration of POMCA, the rats of cerebral ischemia group were further divided into seven sub-groups, 2 h, 4 h, 6 h, 12 h, 18 h, 24 h and 30 hours. The hemispheric ratio was detected by staining with 2% 2,3,5-triphenyltetrazolium chloride solution, and brain water content was assayed by dry/wet ratio 2 h, 4 h, 6 h, 12 h, 18 h, 24 h and hours after POMCA. Results There was a focal cerebral infarction in the rats of cerebral ischemia group 4 hours after POMCA. There was no significant difference in hemispheric ratio between 4 hours and 6 hours after POMCA by One-way ANOVA (P = 0.091). Compared with 6 h sub-group, the hemispheric ratio increased significantly in 12 h, 18 h, 24 h and 30 h sub-groups (P < 0.01), and the peak was in the 24 h sub-group. The brain water content began to increase 4 hours after POMCA and aggravated 6 hours later, and reached the peak 24 hours after POMCA. The brain water content of the non-ischemic hemisphere increased 18 h,24 h and 30 hours after POMCA. Furthermore, there was a significant correlation between the hemispheric ratio and brain water content ( r = 0.834, P < 0.01). Conclusions The critical point of cerebral infarction and brain edema aggravated is 6 hours after POMCA. Both brain edema and cerebral infarction reach the most serious degree 24 hours after POMCA. It is an important experimental evidence for evaluating the milieu conducive to the pathogenesis, and choosing the suitable time window for the treatment of cerebral infarction and brain edema.
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Objective To assess quickly the potential environmental pollution by using the luciferase transgenic cells. Methods Many electrophile compounds in the environment can generate oxidative stress,so that the transcription of certain protective genes is induced via specific DNA motifs called electrophile response elements (EPREs). We have made a vector containing a single EPRE fused to the TK minimal promoter and the gene encoding firefly luciferase (EPRE-LUC) by adopting bio-molecular techniques. From this vector the stable LUC expression vector regulated by EPRE had been successfully reconstructed. This reporter construct was transfected into HeLa cells,and the clones resistant to G418 were selected. The resistant cells were treated by the different concentrations of sodium arsenate(NaAsO2),cadmium chloride (CdCl2),mercury chloride(HgCl2) and diethyl mateate (DEM). After that,the expression of luciferase was determined by luciferase assay kit. Results The correct construct frame of LUC reporter vector regulated by EPRE was identified by DNA sequencing; the dose-dependent relationships between the LUC expression and the test substance concentration were found. Among them,the relationship produced by DEM was the most significant. Conclusion The LUC transgenic cells regulated by EPRE have been successfully constructed.
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Objective To identify the emergency factors associated with health-related quality of life(HRQOL)6 months after acute myocardial infarction.Methods HRQOL was assessed in 89 emergency patients 6 months after acute myocardial infarction,using the SF-36 health survey questionnaire.Multivariate linear regression analysis and analysis of covariance were applied to data analysis to identify the emergency factors associated with HRQOL.Results The sum scores of the SF-36 health survey and scores on 4 of the 8 dimensions showed negative linear correlation with age(P
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Objective To study the level changes of tumor necrosis factor ? (TNF ?)and endothelin 1 (ET 1) and the intervention role of vitamin E and vitamin C in the patients with congestive heart failure (CHF).Methods 65 cases of heart failure were randomized into A group of 32 cases and B group of 33 cases.A group were given cardiotonic,diuretic and extending blood vessel drugs;B group were given 200 mg vitamin E once a day and 200 mg vitamin C three times a day,in the duration of two weeks,besides the medications administered to A group.Specific radioimmunoassay and double antibody sandwich ELISA were used to measure the concentrations of TNF ? and ET 1 of 65 cases with heart failure and 32 healthy subjects.Results The TNF ? and ET 1 levels of congestive heart failure patients were significantly higher than those in the control group (P
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Objective To develop a rapid screening method of environmental estrogen in vitro. Methods Estrogen responsive element (ERE) was inserted into the upstream of Lac Z (?-galactosidase ) reporter gene and the reporter gene was regulated under estrogen receptor(ER) in the recombinant yeast cells by the molecular biological technique. When the yeast cells was affected by environmental estrogen, conformational change of ER lead to expression through binding to ERE. There exist the functional relationships between the expression and the pollution degree of environmental estrogen. Therefore, the pollution degree can be reflected by assaying the activity of ?-galactosidase. Results It was identified by PCR that recombinant yeast cell, whose Lac Z reporter gene regulated under estrogen receptor, was successfully reconstructed. The experimental results showed that the time-dose-effect response had no significant changes when the recombinant yeast cell bad been exposed to ?-estradiol for 4 and 8 hours respectively; among the three methods of yeast disintegration, the ultrasonic vibration method had more advantage compared with that of the other methods and this dose-effect curve exhibited "S" shape; among 3 test chemical products, ?-estradiol was the most estrogenic activity, biosphenol A take second place, estradiol benzoate was the lowest. Conclusion The assay system of yeast cell for environmental estrogen hormone mediated by estrogen receptor is stable and applicable.
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AIM: To investigate alteration of inward re ctifier potassium current (I K1) in atrial myocytes and mRNA expression of gene Kir2.1 encoding I K1 in atrial myocardial tissue in patients with chronic atrial fibrillation (AF) compared to that with sinus rhythm (SR).METHODS: Single myocytes were isolated by enzymatic dissociation with the chunk method an d the ionic current was recorded using whole cell patch clamp technique. The sem i-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was used to measure the mRNA expression of Kir2.1 in atrial myocardial tissue, and the g ene GAPDH was used as an internal control.RESULTS: (1) The I K1 density was increased in AF group at hyperpolarizing pot entials, at -120 mV the current densities was (-5.71?0.65) pA/pF in AF group (n=28 cells from 7 patients) and (-4.26?1.22) pA/pF in SR group (n=35 cells from 9 patients) (P0.05).CONCLUSIONS: The increase in I K1 at hyperpolarizing potentials may be related to th e atrial electrophysiological remodeling in chronic human AF. The increased I K1 density in atrial myocytes in AF group without alteration of Kir2.1 mRNA expression in atrial tissue suggests that I K1 may be mediated at post-transcriptional levels.