Objective To investigate the protective effects of hydrogen-rich water postconditioning on glutamate (Glu) mediated ischemia/reperfusion (I/R) injury in isolated brain slices of neonatal rats and explore its mechanism of action.Methods The brains of Sprague-Dawley (SD) neonatal rats aged 7 days were cut into slices and cultured. And then the cultured slices were randomly divided into the normal control group, Glu injury group (1 mmol/L Glu for 30-minute injury), hydrogen-rich water postconditioning group (after Glu injury for 30 minutes, cultured with complete medium containing 100μmol/L of hydrogen-rich water), once per 3 hours to change the medium for totally 24 hours, each group having 12 holes. The brain slices were stained by hematoxylin-eosin (HE) staining to observe the changes of nerve cells. The lactate dehydrogenase (LDH) release rates, the numbers of nissl bodies and the basic fibroblast growth factor (bFGF) in each brain slice were determined to evaluate the degree of cerebral neuronal damage.Results Compared with the normal control group, the number of nerve cells was rare, and the structure not complete; the LDH release rate and the number of bFGF were increased significantly in Glu injury groups [LDH release rates: (50.66±4.93)% vs. (20.15±5.14)%, bFGF (cells/400 power field): 22.79±2.13 vs. 4.13±1.17, both P < 0.01); the Nissl body was decreased (cells/400 power field: 11.81±2.69 vs. 47.10±3.78,P < 0.01) in Glu injury group. Compared with Glu injury group, the morphological structure of brain nerve cells was restored, the LDH release rate was reduced [(39.13±3.66)% vs. (50.66±4.93)%]; bFGF was decreased (cells/400 power field: 14.22±1.22 vs. 22.79±2.13), and the Nissl body was increased (cells/400 power field: 23.25±6.05 vs. 11.81±2.69) in hydrogen-rich water postconditioning group (allP < 0.05).Conclusions Hydrogen-rich water postconditioning has protective effects on rat brain slices with I/R injury induced by Glu. Its mechanism was possibly related to the reduction of free radicals, calcium overload and inflammatory factors induced by excitatory amino acids toxicity, resulting in inhibition of cell apoptosis.

of apoptosis-related gene.

Objective To investigate the protective effects and mechanisms of propofol and Xingnaojing injection on different characteristic injuries in cerebrocortical slices of newborn rats in vitro. Methods The cerebral cortex of the 7 days-old Sprague-Dawley(SD)neonatal rat was cut into slices. 2,3,5-Triphenyl Tetrazolium(TTC) was used to stain the slices to judge their activities,afterwards they were randomly divided into seven different groups (each,n=12):normal control group(group A),glutamate(Glu)injury group(group B),hydrogen dioxide(H2O2) injury group(group C),propofol preconditioning before Glu injury group(group D),Xingnaojing preconditioning before Glu injury group(group E),propofol preconditioning before H2O2 injury group(group F), Xingnaojing preconditioning before H2O2 injury group(group G). On the 3rd day,the pre-medical treatments or pre-conditionings for D,E,F and G groups were carried out for 24 hours(the concentration of propofol:20 mg/L,the concentration of Xingnaojing:10 μg/mL);the slices were successfully incubated for 4 days,afterwards they were immersed in 1 mmol/L Glu and 0.1 mmol/L H2O2 for 30 minutes respectively to establish the injury models which had no pre-treatment,finally all the groups were transferred into normal cultural medium to incubate till the 7th day. In the above processes,the group A had no specific medical treatment. After all the operations,the changes in brain tissue and cell morphology,the quantity of Nissl body(NISSL)stained by its stain,and the proportion of cells stained with red and green dye after the slices in various groups stained with propidium iodide-acridine orange(PI-AO)were observed,and the apoptosis rate was tested by flow cytometry. Results ①Morphological observation of brain slices:on the 3rd day,the slices appeared mild edematous,3-5 days later,the edema gradually disappeared. Until the 6th day, a large number of typical nerve cells and a few glial cells were seen;on the 7th day,the growth of cells reached the peak,and afterwards,gradually apoptosis played the leading role.②Morphological observation of brain slices stained by hematoxylin-eosin(HE)stain:the neurons of group A presented multilateral-or shuttle-shaped. The cell numbers of groups B and C were significantly lower than the number of group A. In the neuron number sequence,the positions of the numbers of groups D,E,F,G were located in the interval between the number of group A and those of groups B and C,and there were differences in number among groups.③NISSL:Nissl-body of group A could be clearly seen. The numbers of Nissl-body in groups B and C were significantly reduced compared with the number in group A(cell/HP:8.8±2.5,10.3±2.5 vs. 28.9±5.1,both P<0.05). The numbers of Nissl-body in groups D and E were obviously increased compared with the number in group B,and the greater increase being in group D(21.5±4.7 vs. 13.4±3.1, P<0.05). The numbers of Nissl-body in groups F and G were markedly increased compared with the number in group C ,and the greater increase being in group F(23.9±1.9 vs. 19.2±4.1,P<0.05). ④ Double staining with PI-AO:in group A,nearly the total number of nuclei presented fluorescent green in color. In groups B and C,a large number of neurons appeared two types of fluorescence and their edges blurred. The proportions of red staining of neuron cytoplasm in groups D and E were lower than the proportion in group B,and the greater decrease being in group D. The proportions of red staining of neuron cytoplasm in groups F and G were lower than the proportion in group C ,and the greater decrease being in group F.⑤Apoptosis rate:the apoptosis rates of groups B and C were higher than the rate of group A〔(22.00±0.64)%,(21.28±1.44)%vs.(8.57±0.67)%,P<0.05〕;the apoptosis rates of groups D and E were lower than group B,the decrease in group D being greater〔(11.94±0.57)%vs.(18.17±0.65)%,P<0.05〕;the apoptosis rates of groups F and G were much lower than the rate of group C,the decrease in group F being greater〔(10.54±1.24)% vs.(13.12±0.13)%,P<0.05〕. Conclusion The pre-treatment of propoful or Xingnaojing injection has protective effect on Glu or H2O2 injury of in vitro rat cerebrocortical slices,and upon the same injury,the brain protective effect of propoful is more powerful than that of Xingnaojing injection.

Objective To observe the sedative effects and analyze the cost-benefit of dexmedetomidine and midazolam for severe patients undergoing mechanical ventilation (MV) in intensive care unit (ICU). Methods A prospective randomized controlled trial was conducted. Eighty patients undergoing MV (24 hours < time of MV < 72 hours) with tracheal intubation and necessity of analgesic therapy in ICU from January 2014 to October 2014 in Affiliated Hospital of Guiyang Medical College were divided into midazolam group (39 cases) and dexmedetomidine group (41 cases) by random numerical table method. Both groups used intravenous continuous pump infusion of fentanyl 0.7 - 1.5μg·kg-1·h-1 as an analgesic therapy. The analgesic goal was critical care pain observation tool (COPT) score kept at 0 - 3, and the score was taken once per hour; when COPT score > 4, 0.5μg/kg fentanyl was added, when the analgesic goal was reached, the sedative treatment was given. In midazolam group, the patients received midazolam whose loading dose was 0.05 mg/kg intravenous injection (IV) in 2 minutes, followed by continuous IV pump infusion 0.03 - 0.30 mg·kg-1·h-1. In dexmedetomidine group, the patients received dexmedetomidine whose loading dose was slowly intravenous pump infusion of 0.5 - 1.0μg/kg, followed by continuous pump IV infusion of 0.2 - 0.7μg·kg-1·h-1; the sedation goal was richmond agitation-sedation scale (RASS) at 0 - 2, the score being taken once per hour, and as RASS > 0 point, the dosage of sedative was increased, and as RASS < -2, the dosage of sedative was reduced or discontinued. During the course of study, the heart rate (HR), blood pressure, the amount of sedative and analgesic used, duration of MV, extubation time, ICU stay time, total costs of sedative and fentanyl drugs, total ICU treatment costs and adverse reactions of patients were observed.Results Compared with midazolam group, the total amount of sedative used (mg/kg: 0.03±0.01 vs. 3.35±1.39), the dose of sedative used per hour (μg·kg-1·h-1: 0.66±0.13 vs. 59.78±19.44), the dose of fentanyl used (μg·kg-1·h-1: 0.40±0.21 vs. 0.57±0.26), the total costs of fentanyl used per hour (yuan: 1.41±0.86 vs. 2.00±0.84), the total costs in ICU per hour (yuan: 264.42±99.55 vs. 297.80±138.70) in dexmedetomidine group were significantly less (allP < 0.05); compared with midazolam group, the total costs of sedative in dexmedetomidine group was significantly higher (yuan: 8.97±5.05 vs. 7.78±4.22); the duration of MV [hours: 43.58 (39.83, 53.58) vs. 58.58 (46.17, 65.50)], extubation time [hours: 1.00 (1.67, 0.58) vs. 3.67 (2.00, 5.50)] and the time for staying in ICU [hours: 57.25 (47.33, 67.37) vs. 75.58 (64.67, 90.83)] were significantly shorter in dexmedetomidine group (allP < 0.05); the incidences of adverse reactions in dexmedetomidine group were significantly higher [hypotension: 29.27% (12/41) vs. 7.69% (3/39), bradycardia: 24.39% (10/41) vs. 5.13% (2/39), bothP < 0.05]; the incidence of delirium in dexmedetomidine group was lower [2.43% (1/41) vs. 15.38% (6/39),P < 0.05].Conclusion For ICU patients, dexmedetomidine is an ideal effective sedative, as it may shorten the duration of MV, the time for extubation, the period staying in ICU, reduce the dosage of analgesic used and the cost of treatment in ICU.

Objective To explore the application value of control chart in the management of nosocomial infection in intensive care unit (ICU) by using quality control chart to monitor the infectionsin ICU.Methods From October 2011 to June 2016, ventilator-associated pneumonia (VAP), central line-associated bloodstream infection (CLABSI) and catheter-associated urinary tract infection (CAUTI), namely the three catheters, occurred in ICU of the Affiliated Hospital of Guizhou Medical University were monitored and recorded monthly, then the data was imput into the Excel, and the data was analyzed using SPSS. According to the properties of the data, control chart was derived for monitoring nosocomial infections, finding out problems and for taking actions on time.Results From October 2011 to June 2016, the numbers of new patients in ICU were 23-103 cases per month and the median was 45.00 (39.00, 55.50) cases per month. The numbers of new VAP patients were 0-7 cases per month which median was 3.00 (1.00, 4.00) cases per month and the VAP rates were 0-22.58 cases per 1000 ventilation-days which median was 8.62 (3.28, 12.10) cases per 1000 ventilation-days. The numbers of new CLABSI patients were 0-3 cases per month which median was 0.00 (0.00, 1.00) cases per month and the CLABSI rates were 0-14.82 cases per 1000 catheter-days which median was 0.00 (0.00, 5.38) cases per 1000 catheter-days. The numbers of new CAUTI patients were 0-8 cases per month which median was 1.00 (0.00, 2.00) cases per month and the CAUTI rates were 0-14.06 cases per 1000 catheter-days which median was 3.02 (0.00, 5.86) cases per 1000 catheter-days. 57 points of the three catheter-associated infections incidences were continuously monitored monthly, in which some data points overstepped the warning limit, only 1 CAUTI infection incidence overstepped the control limit, the other monthly three catheter-associated infections incidences were in the control range and had no abnormal arrangement occurred, so all of them were in a controlled state. By using the control chart, the situation of nosocomial infections were analyzed scientifically and intuitively, the existing problems were discussed in time, the improvement programs were made, and the three catheter-associated infections were in a controlled state.Conclusion Control chart has the characteristics of simple operation, intuitive results, and finding problems on time, so it can be used in daily monitoring of nosocomial infection and is worthy of generalization.

Objective To explore the prognostic role of nutritional benefit assessment (NUTRIC score), nutritional risk screening 2002 (NRS 2002), traditional nutritional laboratory indicators albumin (ALB) and prealbumin (PA) in critically ill patients. Methods A historical-prospective cohort study was conducted. The data of 427 patients admitted to Department of Critical Care Medicine of the Affiliated Hospital of Guizhou Medical University from February 2014 to October 2014 were retrospectively analyzed, and thereafter a follow-up of 275 critically ill patients from November 2014 to April 2015 prospectively enrolled was performed. 261 patients were enrolled finally. Patients were divided into death group and survival group according to 28-day and 90-day outcome, the baseline data, acute physiology and chronic health evaluationⅡ (APACHE Ⅱ) score, sequential organ failure assessment (SOFA) score, NRS 2002, NUTRIC score, ALB and PA were compared between the two groups. Logistic regression analysis was used to find risk factors for 28-day and 90-day prognosis. Results ① NRS 2002 score of all the 261 patients were greater than or equal to 3 with 100% nutritional risk. The patients in NUTRIC score 5-9 group had lower ALB and PA, higher NRS 2002 score, longer mechanical ventilation time and length of intensive care unit (ICU) stay, which indicated they were more serious. ② Twenty eight-day mortality was 20.7% (54 died from 261). Compared with survival group, the patients in death group had higher APACHE Ⅱ, SOFA, and NUTRIC scores [29.00 (22.75, 34.25) vs. 24.00 (20.00, 28.00), 10.0 (8.0, 13.0) vs. 9.0 (7.0, 11.0), 6.37±1.84 vs. 5.59±1.64, all P < 0.01], and longer days from hospital to ICU admission and mechanical ventilation time in ICU [1.5 (0, 9.2) days vs. 0 (0, 4.0) days, 6.0 (4.0, 11.0) days vs. 4.2 (2.5, 7.8) days, both P < 0.05]. It was revealed by logistic regression analysis that APACHE Ⅱ score [odds ratio (OR) = 1.089, 95% confidence interval (95%CI) = 1.039-1.141, P = 0.000] and days from hospital to ICU admission (OR = 1.042, 95%CI = 1.014-1.071, P = 0.003) were the independent risk factors for 28-day death in critically ill patients. ③ Ninety-day mortality was 42.5% (111 died from 261). Compared with the survival group, the death group patients were older with higher APACHE Ⅱ, SOFA, NRS 2002, and NUTRIC scores [age (years): 64.44±18.11 vs. 54.25±19.66, APACHE Ⅱ: 27.00 (23.00, 31.00) vs. 23.00 (20.00, 27.00), SOFA: 10.0 (8.0, 12.0) vs. 9.0 (7.0, 11.0), NRS 2002: 5.08±1.47 vs. 4.67±1.41, NUTRIC: 6.32±1.58 vs. 5.33±1.68], ALB was significantly reduced [g/L: 27.70 (23.05, 32.00) vs. 30.73 (26.90, 34.20)], and mechanical ventilation time in ICU was extended obviously [days: 5.7 (3.6, 11.0) vs. 3.9 (2.4, 7.0), all P < 0.05]. It was revealed by logistic regression analysis that old age (OR = 1.019, 95%CI = 1.002-1.037, P = 0.029) and NUTRIC score (OR = 1.211, 95%CI = 0.983-1.491, P = 0.072) were the independent risk factors for 90-day death probability, and ALB probability was the protect factor for 90-day death (OR = 0.954, 95%CI = 0.916-0.994, P = 0.024). Conclusion It was NUTRIC score but not NRS 2002, ALB and PA predicted 90-day mortality in critically ill patients.

Objective Assess the value of several biomarkers and disease severity scores for the prognostic assessment of sepsis.Methods The clinical data of adult patients, who met the diagnostic criteria for Sepsis-3 and admitted to the intensive care unit (ICU) of Affiliated Hospital of Guizhou Medical University from January 2015 to December 2016 were retrospectively analyzed. These patients were divided into survival group and death group. The levels of serum lactate (Lac), lactate clearance rate of 24 hours later (24 h LCR), procalcitonin (PCT), quick sequential organ failure assessment (qSOFA) score, SOFA score, simplified acute physiology score Ⅱ (SAPS Ⅱ), acute physiology and chronic health evaluation scoring system Ⅱ (APACHE Ⅱ) score were determined, and the receiver operating characteristic curve (ROC) were used to analyze the prognostic value of the indicators above.Results 110 of 152 sepsis patients survived, while the others died. Compared with survival group, serum Lac, PCT, SOFA score, qSOFA score, SAPS Ⅱ score, APACHE Ⅱ score of death group were increased, and 24 h LCR was decreased. SAPS Ⅱ[area under the ROC curve (AUC) = 0.877,P = 0.000, when threshold value was 41.50, sensitivity was 94.3%, specificity was 68.5%], 24 h LCR (AUC = 0.869,P = 0.000, when threshold value was 40.2%, sensitivity was 92.1%, specificity was 75.5%) and SOFA score (AUC = 0.815,P = 0.000, when threshold value was 7.60, sensitivity was 79.9%, specificity was 78.5%) showed better predictive value of sepsis. However, the predictive value of PCT (AUC = 0.759), Lac (AUC = 0.725), qSOFA (AUC = 0.701) and APACHE Ⅱ score (AUC = 0.680) were poorer (AUC = 0.6-0.8). For sepsis caused by abdominal cavity infection, the most accurate index was SOFA score (AUC = 0.889,P = 0.000, when threshold value was 9.50, sensitivity was 81.2%, specificity was 83.5%), and for sepsis caused by pneumonia, the most accurate index was PCT (AUC = 0.891,P = 0.001, when threshold value was 3.95 mg/L, sensitivity was 84.7%, specificity was 94.1%).Conclusion SOFA score and qSOFA score cannot take the place of traditional evaluation index for the evaluation of the prognosis of patients with sepsis.

Causal inference research is a causal test designed to assess the impact of exposures on outcomes.Both experimental and observational studies can be used to examine causal associations between exposure factors and outcomes. Experimental studies are sometimes limited by factors such as ethics or experimental conditions. Observational studies account for a large proportion in clinical studies, but the effectiveness and research value of observational studies will be affected if the design of observational studies is not rigorous and the confounding factors are not well controlled.The Guidelines for controlling confounding factors and reporting results in causal inference studie formulated by a special group of 47 editors from 35 journals from all over the world provide good guidance to researchers. This article interprets the guidelines and hopes to provide help for clinical researchers.

Objective To investigate the effect of hydrogen-rich water on cerebral edema and aquaporin 1 (AQP1) expression in rats with traumatic brain injury (TBI).Methods Ninety male Sprague-Dawley (SD) rats were randomly divided into sham operation group,TBI model group,hydrogen-rich water treatment group (H group),with 30 rats in each group.TBI model was reproduced by weight dropping method.The skulls of rats in sham operation group underwent only craniotomy without direct hit and with bone wax sealed suture.5 mL/kg of hydrogen-rich water injection was given intraperitoneally after model reproduction in H group,and equal amount of normal saline was given in sham and TBI groups,once a day for both groups for 5 days.Six rats from each group were sacrificed at 6,12,24,48 hours and 5 days after evaluating neurological severity scores (NSS).The cerebral cortex was harvested,and the pathological changes in morphology of brain tissue were observed with light microscope.The positive expression of AQP1 in cerebral cortex was observed with immunohistochemistry by light microscopy,the AQP1 mRNA expression in cerebral cortex was determined by real-time fluorescent quantization reverse transcription-polymerase chain reaction (RT-PCR),and the AQP1 protein expression in cerebral cortex was determined by Western Blot.Results ① All rats in sham operation group had a NSS of zero at each time point.NSS of TBI group was obviously raised with time prolongation,and peaked at 24 hours followed by a lower tendency,while the score in H group was significantly lower than that of TBI group,and the difference was the most obvious at 24 hours as compared with TBI group (9.83 ± 2.78 vs.13.50± 2.42,P ＜ 0.05).② It was shown by light microscope that in the TBI group there were pathological changes in cerebral cortex,including obvious irregular arrangement of nerve cells,cerebral edema,obvious bleeding,especially at 24 hours,then the cerebral edema became vanished gradually;and the positive expression of AQP1 in the pia mater at all the time points in the TBI group was significantly increased,and it was most obvious at 24 hours.Compared with TBI group,the pathological changes at time points of 12 hours to 5 days in H group was significantly lessened,and the positive expression of AQP1 in the cerebral pia mater was reduced obviously.③ Compared with sham operation group,the mRNA and protein expressions of AQP1 in cerebral cortex in TBI group were significantly elevated,peaked at 24 hours [AQP1 mRNA (2-△△Ct):7.50±0.26 vs.1,AQP1 protein (gray value):1.986±0.110 vs.0.336±0.034,both P ＜ 0.05],then they gradually declined.The mRNA and protein expressions of AQP1 in cerebral cortex were significantly decreased after hydrogen-rich water treatment [24-hour AQP1 mRNA (2-△△Ct):5.40±0.21 vs.7.50±0.26,24-hour AQP1 protein (gray value):1.246±0.137 vs.1.986±0.110,both P ＜ 0.05].Conclusions The up-regulation of AQP1 mRNA and protein in ratst cerebral cortex after TBI perhaps participates in edema formation which might be involved in the pathophysiology of cerebral edema in TBI.Early treatment with an intraperitoneally injection of hydrogen-rich water is capable of attenuating the extent of TBI-induced up-regulation of AQP1 mRNA and protein,alleviating cerebral edema,and achieving its protective effects.

Objective To investigate the effect of mild hypothermia preconditioning against ischemia/ reperfusion (I/R) injury of cultured primary cortical rats neurons,and to compare the protective effect of mild hypothermia only and with its combination with drugs.Methods Cortical neurons of neonatal Sprague-Dawley (SD) rat within 24 hours after birth were harvested and cultured in vitro.On the 3rd day,the cells were cultured in a medium containing 2.5 mg/L cytosine arabinoside to inhibit the growth of glial cells and fibroblast.Having cultured for 6 days they were randomly divided into blank control group,glutamate damaged group (cultured with 200 μmol/L glutamate for 0.5 hour after washing),mild hypothermia preconditioning group (cultured under 33.5 ℃ for 24 hours before injury induced by glutamate),mild hypothermia combining with edaravone preconditioning group,and the hypothermia combining with propofol preconditioning group (medium containing 100 μmol/L edaravone and 3 mg/L propofol).They were cultured under 33.5 ℃ for 24 hours before injury induced by glutamate.After 24 hours of culturing in various medium,apoptosis ratio was observed by flow cytometry.Cell surviving rate was determined with methylthiazolete trazolium (MTT),c-fos protein expression was assayed,and morphologic change of cells with hematoxylin-eosin (HE) staining under the microscope,and uhrastructure changes were observed after uranyl acetate and lead citrate staining under transmission electron microscope.Results The apoptosis ratio and c-fos protein in glutamate damaged group were significantly higher than those in blank control group [apoptosis ratio:(9.85 ± 0.76)％ vs.(0.94 ± 0.20)％,c-fos (ng/L):6.96 ± 0.75 vs.1.65 ± 0.59,both P＜0.01],the cell surviving rate was significantly lower than that in blank control group [(0.20 ± 0.02)％ vs.(0.97 ± 0.03)％,P＜0.01].Mild hypothermia preconditioning reversed surviving rate,apoptosis ratio and c-fos protein,and the effect of hypothermia combining with propofol preconditioning was obviously better [cell surviving rate:(0.80 ± 0.04)％ vs.(0.20 ± 0.02)％,apoptosis ratio:(2.26 ± 0.54)％ vs.(9.85 ± 0.76)％,c-fos (ng/L):2.98 ± 0.46 vs.6.96 ± 0.75,all P＜0.01].The morphology of cortical neurons in blank control group was normal.Most of the cells in glutamate damaged group showed bluish black cytoplasm with pyknic nuclei,with crimpled axons and of them were fractured,and cell number was obviously decreased.In each pre-conditional groups,decrease in cell number was unconspicuous,and only a few cells showed apoptosis.Under transmission electron microscope,it was found that cell membrane,mitochondria and rough endoplasmic reticulum were intact in blank control group,but with reduction in organelles,severely swollen mitochondria,even with formation of vacuole or pyknosis,serious dilation of rough endoplasmic reticulum,with loss of cristac with loss of vacuoles or pyknosis,and marked dilatation of intemal reticular endoplasm,and loss of cristac with vacuolation and chromatin were observed under electron microscope in glutamate damaged group.Compared with the glutamate damaged group,these pathologic changes were markedly alleviated in protected groups.Conclusions Mild hypothermia preconditioning can inhibit glutamate-induced injury to cortical neurons.The protective effect of mild hypothermia combined with propofol is better.