A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial isc...A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial ischemia-reperfusion （I/R） injury. This tightly orchestrated cata-bolic cellular‘housekeeping’ process provides cells with a new source of energy to adapt to stressful conditions. This process was first described as a pro-survival mechanism, but increasing evidence suggests that it can also lead to the demise of the cell. Autophagy has been implicated in the pathogenesis of multiple cardiac conditions including myocardial I/R injury. However, a debate persists as to whether autophagy acts as a protec-tive mechanism or contributes to the injurious effects of I/R injury in the heart. This controversy may stem from several factors including the va-riability in the experimental models and species, and the methodology used to assess autophagy. This review provides updated knowledge on the modulation and role of autophagy in isolated cardiac cells subjected to I/R, and the growing interest towards manipulating autophagy to increase the survival of cardiac myocytes under conditions of stress-most notably being I/R injury. Perturbation of this evolutionarily conserved intracellular cleansing autophagy mechanism, by targeted modulation through, among others, mammalian target of rapamycin （mTOR） inhibitors, adenosine monophosphate-activated protein kinase （AMPK） modulators, calcium lowering agents, resveratrol, longevinex, sirtuin activators, the proapoptotic gene Bnip3, IP3 and lysosome inhibitors, may confer resistance to heart cells against I/R induced cell death. Thus, therapeutic ma-nipulation of autophagy in the challenged myocardium may benefit post-infarction cardiac healing and remodeling.展开更多
Objective Several studies have indicated that miR-15a,miR-15b and miR-16 may be the important regulators of apoptosis.Since attenuate apoptosis could protect myocardium and reduce infarction size,the present study was...Objective Several studies have indicated that miR-15a,miR-15b and miR-16 may be the important regulators of apoptosis.Since attenuate apoptosis could protect myocardium and reduce infarction size,the present study was aimed to find out whether these miRNAs participate in regulating myocardial ischemia reperfusion （I/R） injury.Methods Apoptosis in mice hearts subjected to I/R was detected by TUNEL assay in vivo,while flow cytometry analysis followed by Annexin V/PI double stain in vitro was used to detect apoptosis in cultured cardiomyocytes which were subjected to hypoxia/reoxygenation （H/R）.Taqman real-time quantitative PCR was used to confirm whether miR-15a/15b/16 were involved in the regulation of cardiac I/R and H/R.Results Compared to those of the controls,I/R or H/R induced apoptosis of cardiomyocytes was significantly iucreased both in vivo （24.4％ ± 9.4％ vs.2.2％ ± 1.9％,P ＜ 0.01,n =5） and in vitro （14.12％ ±0.92％ vs.2.22％ ± 0.08％）.The expression of miR-15a and miR-15b,but not miR-16,was increased in the mice I/R model,and the results were consistent in the H/R model.Conclusions Our data indicate miR-15 and miR-15b are up-regulated in response to cardiac I/R injury,therefore,down-regulation of miR- 15a/b may be a promising strategy to reduce myocardial apoptosis induced by cardiac I/R injury.展开更多
Objective To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitabi- lity and neurofunction after cerebral ischemia-reperfusion injury. Methods After determined awake...Objective To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitabi- lity and neurofunction after cerebral ischemia-reperfusion injury. Methods After determined awake resting motor threshold (MT) and motor evoked potentials (MEPs) of right hindlimbs, 20 Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) reperfusion injury, then rTMS were applied to rTMS group (n = 10) at different time, while control group (n = 10) received no stimulation. A week later, MT and MEPs were evaluated again, as well as neurological deficits and infarct volume. The effects of rTMS and MCAO reperfusion injury on these parameters were analyzed. Results After MCAO reperfusion, both MT level and neurological deficit scores increased, distinct focal infarction formed, and latency of MEP elongated. Compared with the control group, the increased extent of MT and neurological scores of rats receiving rTMS were significantly lower (P < 0.05), as well as the infarct volumes reduced significantly(P < 0.05). But MEP was not affected by rTMS obviously. There was a positive linear correlation between postinjury MT and infarct volume (r = 0.64, P < 0.05). Conclusion rTMS may facilitate neurofunction recovery after cerebral ischemia-reperfusion. Postinjury MT could provide prognostic information after MCAO reperfusion injury.展开更多
Objective Oxidative stress （OS） plays a crucial role in ischemic stroke. Grape seed procyanidin extract （GSPE） was reported to be a critical regulator of OS. We hypothesized that GSPE might also be protective in...Objective Oxidative stress （OS） plays a crucial role in ischemic stroke. Grape seed procyanidin extract （GSPE） was reported to be a critical regulator of OS. We hypothesized that GSPE might also be protective in ischemia-reperfusion brain injury. This study aimed to explore whether GSPE administration can protect mice from ischemia-reperfusion brain injury. Methods Transient middle cerebral artery occlusion （MCAO） was conducted followed by reperfusion for 24 hours to make ischemia-reperfusion brain injury in mice that received GSPE （MCAOG, n=60） or normal saline （MCAONS, n=60）. Sham-operated mice （GSPE group and normal saline group） were set as controls. The neurological severity score （NSS） was used to evaluate neural function impairment 1 hour, 24 hour, 3 days and 7 days after MCAO. Mice underwent brain T2WI imaging with a 3T animal MRI scanner 24 hours after reperfusion, and the stroke volume of brains were calculated according to abnormal signal intensity. Immunohistopathological analysis of brain tissues at 24 h after reperfusion was performed for neuronal nuclear antigen （NeuN）, CD34, Bcl-2, and Bax. Glutathione peroxidation （GSH-Px） activity and the level of malonaldehyde （MDA） of brain tissue were also examined. The above indexes were compared among the groups statistically.Results Significant functional improvement was observed 24 hours after MCAO in MCAOG group compared to MCAONS group （P〈0.05）. MCAOG group had smaller cerebral stroke volume （22.46 ± 11.45 mm3 vs. 47.84±9.06 mm3, P〈0.05） than MCAONS group 24 hours after MCAO. More mature NeuN-immunoreactive neurons and more CD34-positive cells in peri-infarct zones were observed in brain tissue of MCAOG mice 24 h after MCAO than that of MCAONS mice （both P〈0.05）. MCAONS mice had significantly higher number of Bax-positive cells in brain tissue than MCAOG （P〈0.05）. The mean MDA level was significantly lower （P〈0.05） and the GSH-Px activity was significantly higher （P〈0.05） in brains of MCAOG mice compared to those of MCAONS mice. Conclusion GSPE administration protects mice from ischemia-reperfusion brain injury through attenuating oxidative stress and apoptosis, promoting angiogenesis, and activating antioxidant enzyme GSH-Px. GSPE may represent a new therapeutical direction for the treatment of ischemia-reperfusion brain injury.展开更多
BACKGROUND:We aimed to investigate the gene expression of myocardial ischemia/reperfusion injury(MIRI)in patients with acute ST-elevation myocardial infarction(STEMI)using stress and toxicity pathway gene chip technol...BACKGROUND:We aimed to investigate the gene expression of myocardial ischemia/reperfusion injury(MIRI)in patients with acute ST-elevation myocardial infarction(STEMI)using stress and toxicity pathway gene chip technology and try to determine the underlying mechanism.METHODS:The mononuclear cells were separated by ficoll centrifugation,and plasma total antioxidant capacity(T-AOC)was determined by the ferric reducing ability of plasma(FRAP)assay.The expression of toxic oxidative stress genes was determined and verified by oligo gene chip and quantitative real-time polymerase chain reaction(qRT-PCR).Additionally,gene ontology(GO)enrichment analysis was performed on DAVID website to analyze the potential mechanism further.RESULTS:The total numbers of white blood cells(WBC)and neutrophils(N)in the peripheral blood of STEMI patients(the AMI group)were significantly higher than those in the control group(WBC:11.67±4.85×10^(9)/L vs.6.41±0.72×10^(9)/L,P<0.05;N:9.27±4.75×10^(9)/L vs.3.89±0.81×10^(9)/L,P<0.05),and WBCs were significantly associated with creatine kinase-myocardial band(CK-MB)on the first day(Y=8.945+0.018X,P<0.05).In addition,the T-AOC was significantly lower in the AMI group comparing to the control group(12.80±1.79 U/mL vs.20.48±2.55 U/mL,P<0.05).According to the gene analysis,eight up-regulated differentially expressed genes(DEGs)included GADD45A,PRDX2,HSPD1,DNAJB1,DNAJB2,RAD50,TNFSF6,and TRADD.Four down-regulated DEGs contained CCNG1,CAT,CYP1A1,and ATM.TNFSF6 and CYP1A1 were detected by polymerase chain reaction(PCR)to verify the expression at different time points,and the results showed that TNFSF6 was up-regulated and CYP1A1 was down-regulated as the total expression.GO and kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis suggested that the oxidative stress genes mediate MIRI via various ways such as unfolded protein response(UPR)and apoptosis.CONCLUSIONS:WBCs,especially neutrophils,were the critical cells that mediating reperfusion injury.MIRI was regulated by various genes,including oxidative metabolic stress,heat shock,DNA damage and repair,and apoptosis-related genes.The underlying pathway may be associated with UPR and apoptosis,which may be the novel therapeutic target.展开更多
BACKGROUND:Sepsis-induced myocardial injury is one of the major predictors of morbidity and mortality of sepsis.The cytoprotective function of erythropoietin(EPO) has been discovered and extensively studied.However,th...BACKGROUND:Sepsis-induced myocardial injury is one of the major predictors of morbidity and mortality of sepsis.The cytoprotective function of erythropoietin(EPO) has been discovered and extensively studied.However,the cardioprotective effects of EPO on sepsis-induced myocardial injury in the rat sepsis model has not been reported.METHODS:The rat models of sepsis were produced by cecal ligation and perforation(CLP)surgery.Rats were randomly(random number) assigned to one of three groups(n=8 for each group):sham group,CLP group and EPO group(1000 lU/kg erythropoietin).Arterial blood was withdrawn at3,6,12,and 24 hours after CLP.cTnl,BNP,CK-MB,LDH,AST,TNF-a,IL-6,IL-10,and CRP were tested by the ELISA assay.Changes of hemodynamic parameters were recorded at 3,6,12,24 hours after the surgery.Histological diagnosis was made by hematoxylin and eosin.Flow cytometry was performed to examine cell apoptosis,myocardium mitochondrial inner membrane potential,and NF-κB(p65).Survival rate at 7 days after CLP was recorded.RESULTS:In the CLP group,myocardial enzyme index and inflammatory index increased at3,6,12 and 24 hours after CLP compared with the sham group,and EPO significantly blocked the increase.Compared with the CLP group,EPO significantly improved LVSP,LV +dpldt_(max) LV-dp/dt_(min),and decreased LVEDP at different time.EPO blocked the reduction of mitochondrial transmembrane potential,suppressed the cardiomyocyte apoptosis,inhibited the activation of NF-κB,and reduced the production of proinflmmatory cytokines.No difference in the survival rate at 7 days was observed between the CLP group and the EPO group.CONCLUSION:Exogenous EPO has cardioprotective effects on sepsis-induced myocardial injury.展开更多
Objective To study the protective effect of agrimony extracts from different extracting methods on cerebral ischemia-reperfusion injury in rats, in order to optimize the extraction scheme of agrimony.Methods Male rats...Objective To study the protective effect of agrimony extracts from different extracting methods on cerebral ischemia-reperfusion injury in rats, in order to optimize the extraction scheme of agrimony.Methods Male rats were randomly assigned into seven groups: 1. Sham-operated group, 2. Untreated MCAO group (MCAO), 3. Petroleum ether extract of Agrimonia pilosa treated MCAO group (PEA), 4. Ethyl acetate extract of Agrimonia pilosa treated MCAO group (EAEA), 5. Ethanol extract of Agrimonia pilosa treated MCAO group (EEA), 6. Water extract of Agrimonia pilosa treated MCAO group (WEA), 7. Nimodipine treated MCAO group (NP). Intragastrical drug administration (i.g) was performed at 0 and 6 hours after MCAO.Neurological function tests were performed after reperfusion for 24 hours, then the brain was removed for the evaluations of the cerebral infarction volume (percentage of total brain volume) by immunohistochemistry,histological changes (hematoxylin-eosin staining), Na+/K+-ATPase, Ca2+-ATPase (modified method of Svoboda and Mosinger), mRNA expression of Tumor suppressor gene (P53) and hot shock protein (HSP70)(quantitative real-time PCR).Results The neurological function of MCAO group had significantly higher scores than the sham group (P<0.01). The WEA group showed a significantly lower neurological score than the MCAO group (P<0.05),indicating the protective effect of WEA on neurological deficits. The mean infarction volumes of WEA (13.5±6.6%, F=4.75, P<0.01), EEA (19.90±6.90%, F=5.23, P<0.01), PEA (20.40±5.30%, F=4.68,P<0.01) and EAEA (22.50±10.50%, F=6.25, P<0.05) group were all significantly smaller than that of MCAO group (29.40±6.50%). HE staining demonstrated that, compared to the treated groups, the infarcted cerebral tissue of MCAO group had more swelling neural cells, lighter stained nucleus, fewer and irregularly distributed neurons. The activity of Na+/K+-ATPase and Ca2+-ATPase reduced in the MCAO group (3.67±0.48 U/mg,1.28±0.26 U/mg, respectively), and were significantly higher in WEA group (7.56±0.85 U/mg, F=12.65,P=0.010; 3.59±0.22 U/mg, F=8.32, P=0.041, respectively). The MCAO group showed significantly elevated P53 and HSP70 mRNA expressions compared to the sham group (P<0.01, P<0.05). P53 mRNA expressions in Agrimony extracts treated groups were significantly lower than that of the MCAO group (all P<0.01), with the WEA group showing the greatest difference from MCAO group. The HSP70 mRNA level of the treated groups were not significantly different from that of the MCAO group.Conclusions Treatment using water extracts of agrimony can promote the best functional and metabolic recovery for rat model of cerebral ischemia-reperfusion injury, which maybe relate with the upregulation of energy metabolism in nerve cells after MCAO.展开更多
BACKGROUND:Hyperbaric oxygen(HBO)is an effective adjuvant therapy for ischemiareperfusion(I/R)injury of the brain,small intestine and testis in addition to crushing injury.Studies have shown that HBO increases the act...BACKGROUND:Hyperbaric oxygen(HBO)is an effective adjuvant therapy for ischemiareperfusion(I/R)injury of the brain,small intestine and testis in addition to crushing injury.Studies have shown that HBO increases the activity of villi of the ileum 30 minutes after I/R injury.The present study aimed to observe the effect of HBO on apoptosis of epithelial cells in the small intestine during different periods of I/R and to elucidate the potential mechanisms.METHODS:Rats were subjected to 60-minute ischemia by clamping the superior mesenteric artery and 60-minute reperfusion by removal of clamping.The rats were randomly divided into four groups:I/R group,HBO precondition or HBO treatment before ischemia(HBO-P),HBO treatment during ischemia period(HBO-I),and HBO treatment during reperfusion(HBO-R).After 60-minute reperfusion,samples of the small intestine were prepared to measure the level of ATP by using the colorimetric method and immunochemical expression of caspase-3.The levels of TNF-αin intestinal tissue were measured using the enzyme-linked immunosorbent assay method(Elisa).RESULTS:TNF-αlevels were significantly lower in the HBO-I group than in the HBO-P(P<0.05),HBO-R and I/R groups;there was no significant difference between the HBO-R and I/R groups(P>0.05).The expression of caspas-3 was significantly lower in the HBO-I group than in the HBO-P group(P<0.05);it was also significantly lower in the HBO-P group than in the I/R and HBO-R groups(P<0.05).ATP level was significantly lower in the HBO-I group than in the HBO-P group(P<0.05),and also it was significantly lower in the HBO-P group than in the I/R and HBO-R groups(P<0.05).CONCLUSIONS:There is an association between HBO,small intestinal I/R injury,and mucosa apoptosis.HBO maintains ATP and aerobic metabolism,inhibites TNF-αproduction,and thus prevents intestinal mucosa from apoptosis.Best results can be obtained when HBO is administered to patients in the period of ischemia,and no side effects are produced when HBO is given during the Period of Reperfusion.展开更多
In December 2019,coronavirus disease 2019(COVID-19)caused by a novel coronavirus(SARS-CoV-2)broke out in Wuhan,China,and has spread widely all over the world,reaching the pandemic level.[1]According to the latest WHO ...In December 2019,coronavirus disease 2019(COVID-19)caused by a novel coronavirus(SARS-CoV-2)broke out in Wuhan,China,and has spread widely all over the world,reaching the pandemic level.[1]According to the latest WHO report,693,224 cases of COVID-19 were confirmed globally as of March 30,2020,with more than 33,000 deaths.[2]Because COVID-19 is highly contagious and harmful,it is crucial to determine the predictors of severe infection and death for risk stratification and guiding clinical treatment and intervention.展开更多
Objective:To explore the protective effect of remifentanil on mitochondria in rat hepatocytes subjected to ischemia-reperfusion injury and their possible mechanism. Methods:The model of rat hepatic ischemia-reperfusio...Objective:To explore the protective effect of remifentanil on mitochondria in rat hepatocytes subjected to ischemia-reperfusion injury and their possible mechanism. Methods:The model of rat hepatic ischemia-reperfusion injury was used and the effect of remifentanil on the ultrastructure of mitochondria, calcium homeostasis, MDA level in mitochondria were observed. Results: In contrast with the control group, mitochondrial matrix calcium concentration, calcium concentration after calcium uptake, and the quantity of calcium uptake in low and high remifentanil concentration groups and 5-HD group are lower (P<0. 01), and there is no difference in RHD (5-HD+remifentanil) group. The difference in MDA level between groups is insignificant. Conclusion:Remifentanil at clinical concentrations exerts a protective effect on mitochondria in rat hepatocytes subjected to ischemia-reperfusion injury, in which activating the KATP channel may be involved.展开更多
Objective To evaluate the effects and mechanisms of glucose-insulin-potassium(GIK)on post-procedural myocardial injury(PMI)after percutaneous coronary intervention(PCI).Methods A total of 200 non-diabetic patients wit...Objective To evaluate the effects and mechanisms of glucose-insulin-potassium(GIK)on post-procedural myocardial injury(PMI)after percutaneous coronary intervention(PCI).Methods A total of 200 non-diabetic patients with documented coronary heart disease(CHD)were divided into the Group GIK and Group G,with 100 patients in each group.Patients in Group G were given intravenous infusion of glucose solution 2 hours before PCI.As compared,patients in Group GIK were given GIK.Results Both post-procedural creatine phosphokinase isoenzyme MB(CK-MB;62.1±47.8 vs.48.8±52.6 U/L,P=0.007)and cTnI(0.68±0.83 vs.0.19±0.24 ng/mL,P<0.001)in Group GIK were significantly higher than those in Group G.In Group G,9.0%and 4.0%of patients had post-procedural increases in CK-MB 1-3 times and>3 times,which were significantly lower than those in Group GIK(14.0%and 7.0%,respectively;all P values<0.01);13.0%and 7.0%of patients had post-procedural increases in cTnI 1-3 times and>3 times,which were also significantly lower than those in Group GIK(21.0%and 13.0%,respectively;all P<0.001).Pre-procedural(10.2±4.5 vs.5.1±6.3,P<0.001)and post-procedural rapid blood glucose(RBG)levels(8.9±3.9 vs.5.3±5.6,P<0.001)in Group G were higher than those in Group GIK.In adjusted logistic models,usage of GIK(compared with glucose solution)remained significantly and independently associated with higher risk of post-procedural increases in both CK-MB and cTnI levels>3 times.Furthermore,pre-procedural RBG levels<5.0mmol/L were significantly associated with higher risk of post-procedural increases in both CK-MB and cTnI levels.Conclusions In non-diabetic patients with CHD,the administration of GIK may increase the risk of PMI due to hypoglycemia induced by GIK.展开更多
BACKGROUND: We aimed to investigate whether the pressure injury risk mediates the association of left ventricular ejection fraction(LVEF) with all-cause death in patients with acute myocardial infarction(AMI) aged 80 ...BACKGROUND: We aimed to investigate whether the pressure injury risk mediates the association of left ventricular ejection fraction(LVEF) with all-cause death in patients with acute myocardial infarction(AMI) aged 80 years or older.METHODS: This retrospective cohort study included 677 patients with AMI aged 80 years or older from a tertiary-level hospital. Pressure injury risk was assessed using the Braden scale at admission, and three risk groups(low/minimal, intermediate, high) were defined according to the overall score of six different variables. LVEF was measured during the index hospitalization for AMI. All-cause death after hospital discharge was the primary outcome.RESULTS: Over a median follow-up period of 1,176 d(interquartile range [IQR], 722–1,900 d), 226(33.4%) patients died. Multivariate Cox regression analysis showed that reduced LVEF was associated with an increased risk of all-cause death only in the high-risk group of pressure injury(adjusted hazard ratios [HR]=1.81, 95% confidence interval [CI]: 1.03–3.20;P=0.040), but not in the low/minimal-(adjusted HR=1.29, 95%CI: 0.80–2.11;P=0.299) or intermediate-risk groups(adjusted HR=1.14, 95%CI: 0.65–2.02;P=0.651). Significant interactions were detected between pressure injury risk and LVEF(adjusted P=0.003). The cubic spline with hazard ratio plot revealed a distinct shaped curve relation between LVEF and all-cause death among different pressure injury risk groups.CONCLUSIONS: In older patients with AMI, the risk of pressure injury mediated the association between LVEF and all-cause death. The classification of older patients for both therapy and prognosis assessment appears to be improved by the incorporation of pressure injury risk assessment into AMI care management.展开更多
Objective To study the protecting effects and mechanism of betaine hydrochloride on hepatic ischemia-reperfusion injury in rats.Methods Fourty SD rats were randomly divided into 5 groups(8 animals in each group):sham-...Objective To study the protecting effects and mechanism of betaine hydrochloride on hepatic ischemia-reperfusion injury in rats.Methods Fourty SD rats were randomly divided into 5 groups(8 animals in each group):sham-operated control group(A),hepatic ischemia-reperfusion group(B),200 mg·kg-1 400 mg·kg-1 800 mg·kg-1 betaine hydrochloride+hepatic ischemia-reperfusion group(C、D、E).betaine hydrochloride was administered to animals byoral route in group C、D、E for 7 days before ischemia.A、B group was administered with NS.Made the animal model of part hepatic ischemia-reperfusion.Serum alanine aminotransferase(ALT),aspartate aminotransferase(AST)levels in the blood and themalondialdehyde(MDA),superoxide dismutase(SOD),protein content in hepatic tissue were determined after the liver had been reperfused for 24 hours;the hepatic tissue was examined under lightmicroscope and the cell apoptosis was demonstrated with flow cytometry.Results ALT,AST,MDA increased and SOD decreased significantly in B group when compared those in the A group(P<0.05),Hepatic apoptosis was significantly increased;ALT,AST,MDA decreased and SOD increased significantly in betaine hydrochloride 200 mg·kg-1(C)group when compared those in the B group(P<0.05).Hepatic apoptosis was significantly lower,The histologic changes of the liver tissue under lightmicroscope in the C group was more easer than in the I/R group(B).Conclusions Betaine hydrochloride has the ability to scavenge oxygen free radical(OFR),reduce lipid peroxidation and inhibition of apoptosis.So it can protect the rats liver damaged by ischemia-reperfusion.展开更多
Myocardial ischemia reperfusion results in an increase in intracellular sodium concentration, which secondarily increases intracellular calcium via Na+ -Ca2+ exchange, resulting in cellular injury. Endoxin is an endog...Myocardial ischemia reperfusion results in an increase in intracellular sodium concentration, which secondarily increases intracellular calcium via Na+ -Ca2+ exchange, resulting in cellular injury. Endoxin is an endogenous medium of digitalis receptor and can remarkably inhibit Na+ /K+-ATPase activity. Although the level of plasma endoxin is significantly higher during myocardial ischemia, its practical significance is unclear. This research is to investigate whether endoxin is one of important factors involved in myocardial ischemia reperfusion injury, Ischemia reperfusion injury was induced by 30 min of global ischemia and 30 min of reperfusion in isolated rat hearts. Heart rate (HR), left ventricular developed pressure (LVDP) , and its first derivative (±dp/dt max) were recorded. The endoxin contents, intramitochondrial Ca2+ contents, and the Na+ /K+ -ATPase activity in myocardial tissues were measured. Myocardial damages were evaluated by electron microscopy. The endoxin and intramitochondrial Ca2+ contents in myocardial tissues were remarkably higher, myocardial membrane ATPase activity was remarkably lower, the cardiac function was significantly deteriorated, and myocardial morphological damages were severe in myocardial ischemia reperfusion group vs. control. Anti-digoxin antiserum (10, 30 mg/kg) caused a significant improvement in cardiac function (LVDP and±dp/dtmax), Na+/K+-ATPaseactivity, and myocardial morphology, and caused a reduction of endoxin and intramitochondrial Ca contents in myocardial tissues. In the present study, the endoxin antagonist, anti-digoxin antiserum, protected the myocardium against the damages induced by ischemia reperfusion in isolated rat hearts. The results suggest that endoxin might be one of main factors mediating myocardial ischemia reperfusion injury.展开更多
Using the cat cardiopulmonary bypass, the present study was designed to ascertain whether continuous warm blood cardiaplegia can prevent heart arrest from myocardial ischemia and reperfusion injury. Forty -two cats we...Using the cat cardiopulmonary bypass, the present study was designed to ascertain whether continuous warm blood cardiaplegia can prevent heart arrest from myocardial ischemia and reperfusion injury. Forty -two cats weighing 3-3. 5 kg were divided at random into 7 groups. The hearts were not subjected to ischemia/reperfusion in group 1, whereas subjected to 180 min arrest with different myocardial protective methods in group Ⅱ-Ⅳ (namely,with intermittent cold blood cardiaplegia in group Ⅱ, with continuous cold blood cardiaplegia in group Ⅲ, and with continuous warm blood cardiaplegia in group Ⅳ), and subjected to 60 min reperfusion after 180 min arrest on the basis of group Ⅱ-Ⅳ in groups Ⅴ-Ⅶ. One hundred and eighty minutes after cardiac arrest ,mitochondrial function was slightly depressed in group Ⅲ , significantly depressed in group Ⅱ , and normal in group Ⅳ. Mitochondrial function was markedly depressed in group Ⅴ-Ⅶ 180 min after arrest and 60 min after reperfusion , but remained almost normal in group Ⅶ. The levels of ATP content decreased 180 min after arrest in group ⅡⅡ-Ⅲ,but in group Ⅲ myocardial ATP content was maitained at a higher level than in group Ⅲ. In group Ⅳ myocardial ATP content remained normal after 180 min after arrest. MDA content slightly increased in group Ⅲ,significantly increased in group Ⅱ. After reperfusion MDA content rose to a higher level in group Ⅴ-Ⅶ. But MDA content was almost normal in the hearts protected with continuous warm blood cardiaplegia. Our data indicated that the method of continuous warm blood cardiaplegia is safe and effective and represents a new conceptual approach to maintaining excellent myocardial preservation during cardiac arrest. The results also indicated that continuous cold blood cardiaplegia was better than intermittent cold blood cardiaplegia in relation to myocardial protection.展开更多
BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBO...BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains unknown.Hence,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic gun.METHODS:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)groups.In the cREBOA and C-pREBOA groups,the balloon was inflated for 60 min.The hemodynamic and laboratory values were compared at various observation time points.Tissue samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin staining.RESULTS:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all P<0.05).The total volume of blood loss was markedly lower in the cREBOA group(493.14±127.31 mL)compared with other groups(P<0.01).The pH was significantly lower at 180 min in the cREBOA and S-pREBOA groups(P<0.05).At 120 min,the S-pREBOA group showed higher alanine aminotransferase(P<0.05)but lower blood urea nitrogen compared with the cREBOA group(P<0.05).CONCLUSION:In this trauma model with liver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent hemorrhage.Extended tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.展开更多
文摘A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial ischemia-reperfusion （I/R） injury. This tightly orchestrated cata-bolic cellular‘housekeeping’ process provides cells with a new source of energy to adapt to stressful conditions. This process was first described as a pro-survival mechanism, but increasing evidence suggests that it can also lead to the demise of the cell. Autophagy has been implicated in the pathogenesis of multiple cardiac conditions including myocardial I/R injury. However, a debate persists as to whether autophagy acts as a protec-tive mechanism or contributes to the injurious effects of I/R injury in the heart. This controversy may stem from several factors including the va-riability in the experimental models and species, and the methodology used to assess autophagy. This review provides updated knowledge on the modulation and role of autophagy in isolated cardiac cells subjected to I/R, and the growing interest towards manipulating autophagy to increase the survival of cardiac myocytes under conditions of stress-most notably being I/R injury. Perturbation of this evolutionarily conserved intracellular cleansing autophagy mechanism, by targeted modulation through, among others, mammalian target of rapamycin （mTOR） inhibitors, adenosine monophosphate-activated protein kinase （AMPK） modulators, calcium lowering agents, resveratrol, longevinex, sirtuin activators, the proapoptotic gene Bnip3, IP3 and lysosome inhibitors, may confer resistance to heart cells against I/R induced cell death. Thus, therapeutic ma-nipulation of autophagy in the challenged myocardium may benefit post-infarction cardiac healing and remodeling.
文摘Objective Several studies have indicated that miR-15a,miR-15b and miR-16 may be the important regulators of apoptosis.Since attenuate apoptosis could protect myocardium and reduce infarction size,the present study was aimed to find out whether these miRNAs participate in regulating myocardial ischemia reperfusion （I/R） injury.Methods Apoptosis in mice hearts subjected to I/R was detected by TUNEL assay in vivo,while flow cytometry analysis followed by Annexin V/PI double stain in vitro was used to detect apoptosis in cultured cardiomyocytes which were subjected to hypoxia/reoxygenation （H/R）.Taqman real-time quantitative PCR was used to confirm whether miR-15a/15b/16 were involved in the regulation of cardiac I/R and H/R.Results Compared to those of the controls,I/R or H/R induced apoptosis of cardiomyocytes was significantly iucreased both in vivo （24.4％ ± 9.4％ vs.2.2％ ± 1.9％,P ＜ 0.01,n =5） and in vitro （14.12％ ±0.92％ vs.2.22％ ± 0.08％）.The expression of miR-15a and miR-15b,but not miR-16,was increased in the mice I/R model,and the results were consistent in the H/R model.Conclusions Our data indicate miR-15 and miR-15b are up-regulated in response to cardiac I/R injury,therefore,down-regulation of miR- 15a/b may be a promising strategy to reduce myocardial apoptosis induced by cardiac I/R injury.
文摘Objective To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitabi- lity and neurofunction after cerebral ischemia-reperfusion injury. Methods After determined awake resting motor threshold (MT) and motor evoked potentials (MEPs) of right hindlimbs, 20 Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) reperfusion injury, then rTMS were applied to rTMS group (n = 10) at different time, while control group (n = 10) received no stimulation. A week later, MT and MEPs were evaluated again, as well as neurological deficits and infarct volume. The effects of rTMS and MCAO reperfusion injury on these parameters were analyzed. Results After MCAO reperfusion, both MT level and neurological deficit scores increased, distinct focal infarction formed, and latency of MEP elongated. Compared with the control group, the increased extent of MT and neurological scores of rats receiving rTMS were significantly lower (P < 0.05), as well as the infarct volumes reduced significantly(P < 0.05). But MEP was not affected by rTMS obviously. There was a positive linear correlation between postinjury MT and infarct volume (r = 0.64, P < 0.05). Conclusion rTMS may facilitate neurofunction recovery after cerebral ischemia-reperfusion. Postinjury MT could provide prognostic information after MCAO reperfusion injury.
基金Supported by Peking Union Medical College Youth Research Funds(3332016010)Peking Union Medical College Graduate Studen Innovation Fund(2015-1002-02-09)
文摘Objective Oxidative stress （OS） plays a crucial role in ischemic stroke. Grape seed procyanidin extract （GSPE） was reported to be a critical regulator of OS. We hypothesized that GSPE might also be protective in ischemia-reperfusion brain injury. This study aimed to explore whether GSPE administration can protect mice from ischemia-reperfusion brain injury. Methods Transient middle cerebral artery occlusion （MCAO） was conducted followed by reperfusion for 24 hours to make ischemia-reperfusion brain injury in mice that received GSPE （MCAOG, n=60） or normal saline （MCAONS, n=60）. Sham-operated mice （GSPE group and normal saline group） were set as controls. The neurological severity score （NSS） was used to evaluate neural function impairment 1 hour, 24 hour, 3 days and 7 days after MCAO. Mice underwent brain T2WI imaging with a 3T animal MRI scanner 24 hours after reperfusion, and the stroke volume of brains were calculated according to abnormal signal intensity. Immunohistopathological analysis of brain tissues at 24 h after reperfusion was performed for neuronal nuclear antigen （NeuN）, CD34, Bcl-2, and Bax. Glutathione peroxidation （GSH-Px） activity and the level of malonaldehyde （MDA） of brain tissue were also examined. The above indexes were compared among the groups statistically.Results Significant functional improvement was observed 24 hours after MCAO in MCAOG group compared to MCAONS group （P〈0.05）. MCAOG group had smaller cerebral stroke volume （22.46 ± 11.45 mm3 vs. 47.84±9.06 mm3, P〈0.05） than MCAONS group 24 hours after MCAO. More mature NeuN-immunoreactive neurons and more CD34-positive cells in peri-infarct zones were observed in brain tissue of MCAOG mice 24 h after MCAO than that of MCAONS mice （both P〈0.05）. MCAONS mice had significantly higher number of Bax-positive cells in brain tissue than MCAOG （P〈0.05）. The mean MDA level was significantly lower （P〈0.05） and the GSH-Px activity was significantly higher （P〈0.05） in brains of MCAOG mice compared to those of MCAONS mice. Conclusion GSPE administration protects mice from ischemia-reperfusion brain injury through attenuating oxidative stress and apoptosis, promoting angiogenesis, and activating antioxidant enzyme GSH-Px. GSPE may represent a new therapeutical direction for the treatment of ischemia-reperfusion brain injury.
基金National Natural Science Foundation of China(81670220,31270992,and 30800215)Guangdong Provincial Natural Science Foundation(2014A030313086)+2 种基金Guangdong Provincial Science and Technology Plan Project(2015A020212013)Guangzhou Science and Technology Project(201804010007)This research was approved by the Ethics Committee of the First Affiliated Hospital of Sun Yat-sen University([2019]176).
文摘BACKGROUND:We aimed to investigate the gene expression of myocardial ischemia/reperfusion injury(MIRI)in patients with acute ST-elevation myocardial infarction(STEMI)using stress and toxicity pathway gene chip technology and try to determine the underlying mechanism.METHODS:The mononuclear cells were separated by ficoll centrifugation,and plasma total antioxidant capacity(T-AOC)was determined by the ferric reducing ability of plasma(FRAP)assay.The expression of toxic oxidative stress genes was determined and verified by oligo gene chip and quantitative real-time polymerase chain reaction(qRT-PCR).Additionally,gene ontology(GO)enrichment analysis was performed on DAVID website to analyze the potential mechanism further.RESULTS:The total numbers of white blood cells(WBC)and neutrophils(N)in the peripheral blood of STEMI patients(the AMI group)were significantly higher than those in the control group(WBC:11.67±4.85×10^(9)/L vs.6.41±0.72×10^(9)/L,P<0.05;N:9.27±4.75×10^(9)/L vs.3.89±0.81×10^(9)/L,P<0.05),and WBCs were significantly associated with creatine kinase-myocardial band(CK-MB)on the first day(Y=8.945+0.018X,P<0.05).In addition,the T-AOC was significantly lower in the AMI group comparing to the control group(12.80±1.79 U/mL vs.20.48±2.55 U/mL,P<0.05).According to the gene analysis,eight up-regulated differentially expressed genes(DEGs)included GADD45A,PRDX2,HSPD1,DNAJB1,DNAJB2,RAD50,TNFSF6,and TRADD.Four down-regulated DEGs contained CCNG1,CAT,CYP1A1,and ATM.TNFSF6 and CYP1A1 were detected by polymerase chain reaction(PCR)to verify the expression at different time points,and the results showed that TNFSF6 was up-regulated and CYP1A1 was down-regulated as the total expression.GO and kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis suggested that the oxidative stress genes mediate MIRI via various ways such as unfolded protein response(UPR)and apoptosis.CONCLUSIONS:WBCs,especially neutrophils,were the critical cells that mediating reperfusion injury.MIRI was regulated by various genes,including oxidative metabolic stress,heat shock,DNA damage and repair,and apoptosis-related genes.The underlying pathway may be associated with UPR and apoptosis,which may be the novel therapeutic target.
基金supported by a grant from the National Natural Science Foundation of China(81070122)
文摘BACKGROUND:Sepsis-induced myocardial injury is one of the major predictors of morbidity and mortality of sepsis.The cytoprotective function of erythropoietin(EPO) has been discovered and extensively studied.However,the cardioprotective effects of EPO on sepsis-induced myocardial injury in the rat sepsis model has not been reported.METHODS:The rat models of sepsis were produced by cecal ligation and perforation(CLP)surgery.Rats were randomly(random number) assigned to one of three groups(n=8 for each group):sham group,CLP group and EPO group(1000 lU/kg erythropoietin).Arterial blood was withdrawn at3,6,12,and 24 hours after CLP.cTnl,BNP,CK-MB,LDH,AST,TNF-a,IL-6,IL-10,and CRP were tested by the ELISA assay.Changes of hemodynamic parameters were recorded at 3,6,12,24 hours after the surgery.Histological diagnosis was made by hematoxylin and eosin.Flow cytometry was performed to examine cell apoptosis,myocardium mitochondrial inner membrane potential,and NF-κB(p65).Survival rate at 7 days after CLP was recorded.RESULTS:In the CLP group,myocardial enzyme index and inflammatory index increased at3,6,12 and 24 hours after CLP compared with the sham group,and EPO significantly blocked the increase.Compared with the CLP group,EPO significantly improved LVSP,LV +dpldt_(max) LV-dp/dt_(min),and decreased LVEDP at different time.EPO blocked the reduction of mitochondrial transmembrane potential,suppressed the cardiomyocyte apoptosis,inhibited the activation of NF-κB,and reduced the production of proinflmmatory cytokines.No difference in the survival rate at 7 days was observed between the CLP group and the EPO group.CONCLUSION:Exogenous EPO has cardioprotective effects on sepsis-induced myocardial injury.
基金Fund supported by National Science Foundation of China (NSFC) 81503491,81374053, 81630105.
文摘Objective To study the protective effect of agrimony extracts from different extracting methods on cerebral ischemia-reperfusion injury in rats, in order to optimize the extraction scheme of agrimony.Methods Male rats were randomly assigned into seven groups: 1. Sham-operated group, 2. Untreated MCAO group (MCAO), 3. Petroleum ether extract of Agrimonia pilosa treated MCAO group (PEA), 4. Ethyl acetate extract of Agrimonia pilosa treated MCAO group (EAEA), 5. Ethanol extract of Agrimonia pilosa treated MCAO group (EEA), 6. Water extract of Agrimonia pilosa treated MCAO group (WEA), 7. Nimodipine treated MCAO group (NP). Intragastrical drug administration (i.g) was performed at 0 and 6 hours after MCAO.Neurological function tests were performed after reperfusion for 24 hours, then the brain was removed for the evaluations of the cerebral infarction volume (percentage of total brain volume) by immunohistochemistry,histological changes (hematoxylin-eosin staining), Na+/K+-ATPase, Ca2+-ATPase (modified method of Svoboda and Mosinger), mRNA expression of Tumor suppressor gene (P53) and hot shock protein (HSP70)(quantitative real-time PCR).Results The neurological function of MCAO group had significantly higher scores than the sham group (P<0.01). The WEA group showed a significantly lower neurological score than the MCAO group (P<0.05),indicating the protective effect of WEA on neurological deficits. The mean infarction volumes of WEA (13.5±6.6%, F=4.75, P<0.01), EEA (19.90±6.90%, F=5.23, P<0.01), PEA (20.40±5.30%, F=4.68,P<0.01) and EAEA (22.50±10.50%, F=6.25, P<0.05) group were all significantly smaller than that of MCAO group (29.40±6.50%). HE staining demonstrated that, compared to the treated groups, the infarcted cerebral tissue of MCAO group had more swelling neural cells, lighter stained nucleus, fewer and irregularly distributed neurons. The activity of Na+/K+-ATPase and Ca2+-ATPase reduced in the MCAO group (3.67±0.48 U/mg,1.28±0.26 U/mg, respectively), and were significantly higher in WEA group (7.56±0.85 U/mg, F=12.65,P=0.010; 3.59±0.22 U/mg, F=8.32, P=0.041, respectively). The MCAO group showed significantly elevated P53 and HSP70 mRNA expressions compared to the sham group (P<0.01, P<0.05). P53 mRNA expressions in Agrimony extracts treated groups were significantly lower than that of the MCAO group (all P<0.01), with the WEA group showing the greatest difference from MCAO group. The HSP70 mRNA level of the treated groups were not significantly different from that of the MCAO group.Conclusions Treatment using water extracts of agrimony can promote the best functional and metabolic recovery for rat model of cerebral ischemia-reperfusion injury, which maybe relate with the upregulation of energy metabolism in nerve cells after MCAO.
文摘BACKGROUND:Hyperbaric oxygen(HBO)is an effective adjuvant therapy for ischemiareperfusion(I/R)injury of the brain,small intestine and testis in addition to crushing injury.Studies have shown that HBO increases the activity of villi of the ileum 30 minutes after I/R injury.The present study aimed to observe the effect of HBO on apoptosis of epithelial cells in the small intestine during different periods of I/R and to elucidate the potential mechanisms.METHODS:Rats were subjected to 60-minute ischemia by clamping the superior mesenteric artery and 60-minute reperfusion by removal of clamping.The rats were randomly divided into four groups:I/R group,HBO precondition or HBO treatment before ischemia(HBO-P),HBO treatment during ischemia period(HBO-I),and HBO treatment during reperfusion(HBO-R).After 60-minute reperfusion,samples of the small intestine were prepared to measure the level of ATP by using the colorimetric method and immunochemical expression of caspase-3.The levels of TNF-αin intestinal tissue were measured using the enzyme-linked immunosorbent assay method(Elisa).RESULTS:TNF-αlevels were significantly lower in the HBO-I group than in the HBO-P(P<0.05),HBO-R and I/R groups;there was no significant difference between the HBO-R and I/R groups(P>0.05).The expression of caspas-3 was significantly lower in the HBO-I group than in the HBO-P group(P<0.05);it was also significantly lower in the HBO-P group than in the I/R and HBO-R groups(P<0.05).ATP level was significantly lower in the HBO-I group than in the HBO-P group(P<0.05),and also it was significantly lower in the HBO-P group than in the I/R and HBO-R groups(P<0.05).CONCLUSIONS:There is an association between HBO,small intestinal I/R injury,and mucosa apoptosis.HBO maintains ATP and aerobic metabolism,inhibites TNF-αproduction,and thus prevents intestinal mucosa from apoptosis.Best results can be obtained when HBO is administered to patients in the period of ischemia,and no side effects are produced when HBO is given during the Period of Reperfusion.
文摘In December 2019,coronavirus disease 2019(COVID-19)caused by a novel coronavirus(SARS-CoV-2)broke out in Wuhan,China,and has spread widely all over the world,reaching the pandemic level.[1]According to the latest WHO report,693,224 cases of COVID-19 were confirmed globally as of March 30,2020,with more than 33,000 deaths.[2]Because COVID-19 is highly contagious and harmful,it is crucial to determine the predictors of severe infection and death for risk stratification and guiding clinical treatment and intervention.
文摘Objective:To explore the protective effect of remifentanil on mitochondria in rat hepatocytes subjected to ischemia-reperfusion injury and their possible mechanism. Methods:The model of rat hepatic ischemia-reperfusion injury was used and the effect of remifentanil on the ultrastructure of mitochondria, calcium homeostasis, MDA level in mitochondria were observed. Results: In contrast with the control group, mitochondrial matrix calcium concentration, calcium concentration after calcium uptake, and the quantity of calcium uptake in low and high remifentanil concentration groups and 5-HD group are lower (P<0. 01), and there is no difference in RHD (5-HD+remifentanil) group. The difference in MDA level between groups is insignificant. Conclusion:Remifentanil at clinical concentrations exerts a protective effect on mitochondria in rat hepatocytes subjected to ischemia-reperfusion injury, in which activating the KATP channel may be involved.
基金The report was supported by grants from the Beijing Nova Program(No.Z121107002512053)the Beijing Health System High Level Health Technology Talent Cultivation Plan(No.2013-3-013)+3 种基金Beijing Outstanding Talent Training Program(No.2014000021223ZK32)the National Natural Science Foundation of China(No.81100143)the Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding Support(No.ZYLX 201303)and the National Key Clinical Speciality Construction Project.
文摘Objective To evaluate the effects and mechanisms of glucose-insulin-potassium(GIK)on post-procedural myocardial injury(PMI)after percutaneous coronary intervention(PCI).Methods A total of 200 non-diabetic patients with documented coronary heart disease(CHD)were divided into the Group GIK and Group G,with 100 patients in each group.Patients in Group G were given intravenous infusion of glucose solution 2 hours before PCI.As compared,patients in Group GIK were given GIK.Results Both post-procedural creatine phosphokinase isoenzyme MB(CK-MB;62.1±47.8 vs.48.8±52.6 U/L,P=0.007)and cTnI(0.68±0.83 vs.0.19±0.24 ng/mL,P<0.001)in Group GIK were significantly higher than those in Group G.In Group G,9.0%and 4.0%of patients had post-procedural increases in CK-MB 1-3 times and>3 times,which were significantly lower than those in Group GIK(14.0%and 7.0%,respectively;all P values<0.01);13.0%and 7.0%of patients had post-procedural increases in cTnI 1-3 times and>3 times,which were also significantly lower than those in Group GIK(21.0%and 13.0%,respectively;all P<0.001).Pre-procedural(10.2±4.5 vs.5.1±6.3,P<0.001)and post-procedural rapid blood glucose(RBG)levels(8.9±3.9 vs.5.3±5.6,P<0.001)in Group G were higher than those in Group GIK.In adjusted logistic models,usage of GIK(compared with glucose solution)remained significantly and independently associated with higher risk of post-procedural increases in both CK-MB and cTnI levels>3 times.Furthermore,pre-procedural RBG levels<5.0mmol/L were significantly associated with higher risk of post-procedural increases in both CK-MB and cTnI levels.Conclusions In non-diabetic patients with CHD,the administration of GIK may increase the risk of PMI due to hypoglycemia induced by GIK.
基金This work was supported by the Key Research and Development Projects of Science&Technology Department of Sichuan Province(2019YFS0351).
文摘BACKGROUND: We aimed to investigate whether the pressure injury risk mediates the association of left ventricular ejection fraction(LVEF) with all-cause death in patients with acute myocardial infarction(AMI) aged 80 years or older.METHODS: This retrospective cohort study included 677 patients with AMI aged 80 years or older from a tertiary-level hospital. Pressure injury risk was assessed using the Braden scale at admission, and three risk groups(low/minimal, intermediate, high) were defined according to the overall score of six different variables. LVEF was measured during the index hospitalization for AMI. All-cause death after hospital discharge was the primary outcome.RESULTS: Over a median follow-up period of 1,176 d(interquartile range [IQR], 722–1,900 d), 226(33.4%) patients died. Multivariate Cox regression analysis showed that reduced LVEF was associated with an increased risk of all-cause death only in the high-risk group of pressure injury(adjusted hazard ratios [HR]=1.81, 95% confidence interval [CI]: 1.03–3.20;P=0.040), but not in the low/minimal-(adjusted HR=1.29, 95%CI: 0.80–2.11;P=0.299) or intermediate-risk groups(adjusted HR=1.14, 95%CI: 0.65–2.02;P=0.651). Significant interactions were detected between pressure injury risk and LVEF(adjusted P=0.003). The cubic spline with hazard ratio plot revealed a distinct shaped curve relation between LVEF and all-cause death among different pressure injury risk groups.CONCLUSIONS: In older patients with AMI, the risk of pressure injury mediated the association between LVEF and all-cause death. The classification of older patients for both therapy and prognosis assessment appears to be improved by the incorporation of pressure injury risk assessment into AMI care management.
文摘Objective To study the protecting effects and mechanism of betaine hydrochloride on hepatic ischemia-reperfusion injury in rats.Methods Fourty SD rats were randomly divided into 5 groups(8 animals in each group):sham-operated control group(A),hepatic ischemia-reperfusion group(B),200 mg·kg-1 400 mg·kg-1 800 mg·kg-1 betaine hydrochloride+hepatic ischemia-reperfusion group(C、D、E).betaine hydrochloride was administered to animals byoral route in group C、D、E for 7 days before ischemia.A、B group was administered with NS.Made the animal model of part hepatic ischemia-reperfusion.Serum alanine aminotransferase(ALT),aspartate aminotransferase(AST)levels in the blood and themalondialdehyde(MDA),superoxide dismutase(SOD),protein content in hepatic tissue were determined after the liver had been reperfused for 24 hours;the hepatic tissue was examined under lightmicroscope and the cell apoptosis was demonstrated with flow cytometry.Results ALT,AST,MDA increased and SOD decreased significantly in B group when compared those in the A group(P<0.05),Hepatic apoptosis was significantly increased;ALT,AST,MDA decreased and SOD increased significantly in betaine hydrochloride 200 mg·kg-1(C)group when compared those in the B group(P<0.05).Hepatic apoptosis was significantly lower,The histologic changes of the liver tissue under lightmicroscope in the C group was more easer than in the I/R group(B).Conclusions Betaine hydrochloride has the ability to scavenge oxygen free radical(OFR),reduce lipid peroxidation and inhibition of apoptosis.So it can protect the rats liver damaged by ischemia-reperfusion.
文摘Myocardial ischemia reperfusion results in an increase in intracellular sodium concentration, which secondarily increases intracellular calcium via Na+ -Ca2+ exchange, resulting in cellular injury. Endoxin is an endogenous medium of digitalis receptor and can remarkably inhibit Na+ /K+-ATPase activity. Although the level of plasma endoxin is significantly higher during myocardial ischemia, its practical significance is unclear. This research is to investigate whether endoxin is one of important factors involved in myocardial ischemia reperfusion injury, Ischemia reperfusion injury was induced by 30 min of global ischemia and 30 min of reperfusion in isolated rat hearts. Heart rate (HR), left ventricular developed pressure (LVDP) , and its first derivative (±dp/dt max) were recorded. The endoxin contents, intramitochondrial Ca2+ contents, and the Na+ /K+ -ATPase activity in myocardial tissues were measured. Myocardial damages were evaluated by electron microscopy. The endoxin and intramitochondrial Ca2+ contents in myocardial tissues were remarkably higher, myocardial membrane ATPase activity was remarkably lower, the cardiac function was significantly deteriorated, and myocardial morphological damages were severe in myocardial ischemia reperfusion group vs. control. Anti-digoxin antiserum (10, 30 mg/kg) caused a significant improvement in cardiac function (LVDP and±dp/dtmax), Na+/K+-ATPaseactivity, and myocardial morphology, and caused a reduction of endoxin and intramitochondrial Ca contents in myocardial tissues. In the present study, the endoxin antagonist, anti-digoxin antiserum, protected the myocardium against the damages induced by ischemia reperfusion in isolated rat hearts. The results suggest that endoxin might be one of main factors mediating myocardial ischemia reperfusion injury.
文摘Using the cat cardiopulmonary bypass, the present study was designed to ascertain whether continuous warm blood cardiaplegia can prevent heart arrest from myocardial ischemia and reperfusion injury. Forty -two cats weighing 3-3. 5 kg were divided at random into 7 groups. The hearts were not subjected to ischemia/reperfusion in group 1, whereas subjected to 180 min arrest with different myocardial protective methods in group Ⅱ-Ⅳ (namely,with intermittent cold blood cardiaplegia in group Ⅱ, with continuous cold blood cardiaplegia in group Ⅲ, and with continuous warm blood cardiaplegia in group Ⅳ), and subjected to 60 min reperfusion after 180 min arrest on the basis of group Ⅱ-Ⅳ in groups Ⅴ-Ⅶ. One hundred and eighty minutes after cardiac arrest ,mitochondrial function was slightly depressed in group Ⅲ , significantly depressed in group Ⅱ , and normal in group Ⅳ. Mitochondrial function was markedly depressed in group Ⅴ-Ⅶ 180 min after arrest and 60 min after reperfusion , but remained almost normal in group Ⅶ. The levels of ATP content decreased 180 min after arrest in group ⅡⅡ-Ⅲ,but in group Ⅲ myocardial ATP content was maitained at a higher level than in group Ⅲ. In group Ⅳ myocardial ATP content remained normal after 180 min after arrest. MDA content slightly increased in group Ⅲ,significantly increased in group Ⅱ. After reperfusion MDA content rose to a higher level in group Ⅴ-Ⅶ. But MDA content was almost normal in the hearts protected with continuous warm blood cardiaplegia. Our data indicated that the method of continuous warm blood cardiaplegia is safe and effective and represents a new conceptual approach to maintaining excellent myocardial preservation during cardiac arrest. The results also indicated that continuous cold blood cardiaplegia was better than intermittent cold blood cardiaplegia in relation to myocardial protection.
基金supported by military logistics scientific research project(AHJ16J004)。
文摘BACKGROUND:Resuscitative endovascular balloon occlusion of the aorta(REBOA)can temporarily control traumatic bleeding.However,its prolonged use potentially leads to ischemia-reperfusion injury(IRI).Partial REBOA(pREBOA)can alleviate ischemic burden;however,its security and eff ectiveness prior to operative hemorrhage control remains unknown.Hence,we aimed to estimate the effi cacy of pREBOA in a swine model of liver injury using an experimental sliding-chamber ballistic gun.METHODS:Twenty Landrace pigs were randomized into control(no aortic occlusion)(n=5),intervention with complete REBOA(cREBOA)(n=5),continuous pREBOA(C-pREBOA)(n=5),and sequential pREBOA(S-pREBOA)(n=5)groups.In the cREBOA and C-pREBOA groups,the balloon was inflated for 60 min.The hemodynamic and laboratory values were compared at various observation time points.Tissue samples immediately after animal euthanasia from the myocardium,liver,kidneys,and duodenum were collected for histological assessment using hematoxylin and eosin staining.RESULTS:Compared with the control group,the survival rate of the REBOA groups was prominently improved(all P<0.05).The total volume of blood loss was markedly lower in the cREBOA group(493.14±127.31 mL)compared with other groups(P<0.01).The pH was significantly lower at 180 min in the cREBOA and S-pREBOA groups(P<0.05).At 120 min,the S-pREBOA group showed higher alanine aminotransferase(P<0.05)but lower blood urea nitrogen compared with the cREBOA group(P<0.05).CONCLUSION:In this trauma model with liver injury,a 60-minute pREBOA resulted in improved survival rate and was effective in maintaining reliable aortic pressure,despite persistent hemorrhage.Extended tolerance time for aortic occlusion in Zone I for non-compressible torso hemorrhage was feasible with both continuous partial and sequential partial measures,and the significant improvement in the severity of acidosis and distal organ injury was observed in the sequential pREBOA.
