The Selective NLRP3-inflammasome inhibitor MCC950 Mitigates Post-resuscitation Myocardial Dysfunction and Improves Survival in a Rat Model of Cardiac Arrest and Resuscitation.

PURPOSE: To investigate the effects of the selective NLRP3 inflammasome inhibitor MCC950 on post-resuscitation myocardial function and survival in a rat model of cardiopulmonary resuscitation (CPR). METHODS: Thirty-six Sprague Dawley rats were randomized into three groups: (1) MCC950, (2) control, and (3) sham. Each group consisted of a 6 h non-survival subgroup (n = 6) and a 48 h survival subgroup (n = 6). Ventricular fibrillation (VF) was induced and untreated for 6 min. CPR was initiated and continued for 8 min. Resuscitation was attempted with a 4 J defibrillation. MCC950 (10 mg/kg) or vehicle was administered via intraperitoneal injection immediately after the return of spontaneous circulation (ROSC). Myocardial function and sublingual microcirculation were measured after ROSC in the non-survival subgroups. Plasma levels of interleukin Iß (IL-1ß) and cardiac troponin I (cTnI) were measured at baseline and 6 h in the non-survival subgroups. Heart tissue was harvested to measure the NLRP3 inflammasome constituents, including NLRP3, apoptosis-associated speck-like protein (ASC), Caspase-1, and IL-1ß. Survival duration and neurologic deficit score (NDS) were recorded and evaluated among survival groups. RESULTS: Post-resuscitation myocardial function and sublingual microcirculation were improved in MCC950 compared with control (p < 0.05). IL-1ß and cTnI were decreased in MCC950 compared to control (p < 0.01). The MCC950 treated groups showed significantly reduced ASC, caspase-1, and IL-1ß compared with the control group (p < 0.05). Survival at 48 h after ROSC was greater in MCC950 (p < 0.05) with improved NDS (p < 0.05). CONCLUSION: Administration of MCC950 following ROSC mitigates post-resuscitation myocardial dysfunction and improves survival.

Cardiopulmonary resuscitation ameliorates myocardial mitochondrial dysfunction in a cardiac arrest rat model.

PURPOSE: Previous studies implicate that the mitochondrial injury may play an important role in the development of post-resuscitation myocardial dysfunction, however few of them are available regarding the ultrastructural alterations of myocardial mitochondria, mitochondrial energy producing and utilization ability in the stage of arrest time (no-low) and resuscitation time (low-flow). This study aimed to observe the dynamic changes of myocardial mitochondrial function and metabolic disorders during cardiac arrest (CA) and following cardiopulmonary resuscitation (CPR). METHODS: A total of 30 healthy male Sprague-Dawley rats were randomized into three groups: 1) VF/CPR: Ventricular fibrillation (VF) was electrically induced, and 5 min of CPR was performed after 10 min of untreated VF; 2) Untreated VF: VF was induced and untreated for 15 min; and 3) Sham: Rats were identically prepared without VF/CPR. Amplitude spectrum area (AMSA) at VF 5, 10 and 15 min were calculated from ECG signals. The rats' hearts were quickly removed at the predetermined time of 15 min after beginning the procedure to gather measurements of myocardial mitochondrial function, high-energy phosphate stores, lactate, mitochondrial ultrastructure, and myocardial glycogen. RESULTS: The mitochondrial respiratory control ratios significantly decreased after CA compared to sham group. CPR significantly increased respiratory control ratios compared with untreated VF animals. A significant decrease of myocardial glycogen was observed after CA, and a more rapid depletion of myocardial glycogen was observed in CPR animals. CPR significantly reduced the tissue lactate. The mitochondrial ultrastructure abnormalities in CPR animals were less severe than untreated VF animals. AMSA decayed during untreated VF; however, it was significantly greater in CPR group than the untreated VF group. In addition, AMSA was clearly positively correlated with ATP, but negatively correlated with myocardial glycogen. CONCLUSION: Impairment of myocardial mitochondrial function and the incapability of utilizing glycogen were observed after CA. Furthermore, optimal CPR might, in part, preserved mitochondrial function and enhanced utilization of myocardial glycogen.

Mild hypothermia protects hippocampal neurons against oxygen-glucose deprivation/reperfusion-induced injury by improving lysosomal function and autophagic flux.

Mild hypothermia has been proven to be useful to treat brain ischemia/reperfusion injury. However, the underlying mechanisms have not yet been fully elucidated. The present study was undertaken to determine whether mild hypothermia protects hippocampal neurons against oxygen-glucose deprivation/reperfusion(OGD/R)-induced injury via improving lysosomal function and autophagic flux. The results showed that OGD/R induced the occurrence of autophagy, while the acidic environment inside the lysosomes was altered. The autophagic flux assay with RFP-GFP tf-LC3 was impeded in hippocampal neurons after OGD/R. Mild hypothermia recovered the lysosomal acidic fluorescence and the lysosomal marker protein expression of LAMP2, which decreased after OGD/R.Furthermore, we found that mild hypothermia up-regulated autophagic flux and promoted the fusion of autophagosomes and lysosomes in hippocampal neurons following OGD/R injury, but could be reversed by treatment with chloroquine, which acts as a lysosome inhibitor. We also found that mild hypothermia improved mitochondrial autophagy in hippocampal neurons following OGD/R injury. Finally,we found that chloroquine blocked the protective effects of mild hypothermia against OGD/R-induced cell death and injury. Taken together, the present study indicates that mild hypothermia protects hippocampal neurons against OGD/R-induced injury by improving lysosomal function and autophagic flux.

Mild hypothermia protects hippocampal neurons from oxygen-glucose deprivation injury through inhibiting caspase-3 activation.

Mild hypothermia (MH) is thought to be one of the most effective therapeutic methods to treat hypoxic-ischemic encephalopathy (HIE) after cardiac arrest (CA). However, its precise mechanisms remain unclear. In this research, hippocampal neurons were cultured and treated with mild hypothermia and Ac-DEVD-CHO after oxygen-glucose deprivation (OGD). The activity of caspase-3 was detected, in order to find the precise concentration of Ac-DEVD-CHO with the same protective role in OGD injury as MH treatment. Western blot and immunofluorescence staining were conducted to analyze the effects of MH and Ac-DEVD-CHO on the expressions of caspase-3, caspase-8, and PARP. The neuronal morphology was observed with an optical microscope. The lactic acid dehydrogenase (LDH) release rate, neuronal viability, and apoptotic rate were also detected. We found that MH (32 °C) and Ac-DEVD-CHO (5.96 µMol/L) had equal effects on blocking the activation of caspase-3 and the OGD-induced cleavage of PARP, but neither had any effect on the activation of caspase-8, which goes on to activate caspase-3 in the apoptotic pathway. Meanwhile, both MH and Ac-DEVD-CHO had similar effects in protecting cell morphology, reducing LDH release, and inhibiting OGD-induced apoptosis in neurons. They also similarly improved neuronal viability after OGD. In conclusion, caspase-3 serves as a key intervention point of the key modulation site or regulatory region in MH treatment that protects neuronal apoptosis against OGD injury. Inhibiting the expression of caspase-3 had a protective effect against OGD injury in MH treatment, and caspase-3 activation could be applied to evaluate the neuroprotective effectiveness of MH on HIE.

Lactate as a Potential Biomarker of Sepsis in a Rat Cecal Ligation and Puncture Model.

We attempted to investigate whether blood lactate is a useful biomarker for sepsis in a rat cecal ligation and puncture (CLP) model. Male Sprague-Dawley rats underwent approximately 75% cecum ligation and two punctures to induce high-grade sepsis. A lactate of 1.64 mmol/L (Youden score of 0.722) was selected as the best cutoff value to predict the onset of sepsis after CLP exposure; 46 of 50 rats who survived 24 hours after the CLP were divided into the L group (lactate < 1.64 mmol/L) and M group (lactate ≥ 1.64 mmol/L). In the M group, the animals had significantly higher murine sepsis scores and none survived 5 days post-CLP, and the rate of validated septic animals, serum procalcitonin, high mobility group box 1, blood urea nitrogen, alanine transaminase, cardiac troponin I, and the wet-to-dry weight ratio were significantly higher compared to the L group. Worsen PaO2/FiO2, microcirculations, and mean arterial pressure were observed in the M group. More severe damage in major organs was confirmed by histopathological scores in the M group compared with the L group. In conclusion, lactate ≥ 1.64 mmol/L might serve as a potential biomarker to identify the onset of sepsis in a rat CLP model.

Mild hypothermia protects against oxygen glucose deprivation/reoxygenation-induced apoptosis via the Wnt/ß-catenin signaling pathway in hippocampal neurons.

Mild hypothermia is thought to be one of the most effective therapies for cerebral ischemia/reperfusion injuries. Our previous research revealed that mild hypothermia inhibits the activation of caspase-3 and protects against oxygen glucose deprivation/reoxygenation (OGD/R)-induced injury in hippocampal neurons. However, the mechanisms behind the activation of caspase-3 remain unclear. The aims of this study were to determine whether the protective effects of mild hypothermia were exerted through the Wnt/ß-catenin signaling pathway. We found that, under OGD/R conditions, the pathway was down regulated, but mild hypothermia induced the reactivation of the Wnt/ß-catenin signaling pathway, which had been suppressed by OGD/R injury. Mild hypothermia also caused the down regulation of the expression of apoptosis promoting proteins (Bax cleaved caspase-3), up-regulated the expression of apoptosis inhibiting proteins (Bcl-2), and ameliorated OGD/R injury-induced apoptosis. The protective effects of mild hypothermia were blocked by DKK1 (an antagonist of the canonical Wnt signaling pathway). Taken together, these results indicate that the Wnt/ß-catenin signaling pathway mediates the protective effects of mild hypothermia against OGD/R-induced apoptosis. Our study provides evidence that mild hypothermia reactivates the Wnt/ß-catenin signaling pathway, which is suppressed by OGD/R injury, in hippocampal neurons and protects neurons from OGD/R-induced apoptosis via the reactivation of the Wnt/ß-catenin signaling pathway, ultimately suggesting that mild hypothermia could have therapeutic effects on OGD/R-induced apoptosis.

Quality of chest compressions during compression-only CPR: a comparative analysis following the 2005 and 2010 American Heart Association guidelines.

OBJECTIVE: The latest guidelines both increased the requirements of chest compression rate and depth during cardiopulmonary resuscitation (CPR), which may make it more difficult for the rescuer to provide high-quality chest compression. In this study, we investigated the quality of chest compressions during compression-only CPR under the latest 2010 American Heart Association (AHA) guidelines (AHA 2010) and its effect on rescuer fatigue. METHODS: Eighty-six undergraduate volunteers were randomly assigned to perform CPR according to the 2005 AHA guidelines (AHA 2005) or AHA 2010. After the training course and theoretical examination of basic life support, eight min of compression-only CPR performance was assessed. The quality of chest compressions including rate and depth of compression was analyzed. The rescuer fatigue was evaluated by the changes of heart rate and blood lactate, and rating of perceived exertion. RESULTS: Thirty-nine participants in the AHA 2005 group and 42 participants in the AHA 2010 group completed the study. Significantly greater mean chest compression depth and compression rate were both achieved in the AHA 2010 group than in the AHA 2005 group. And significantly greater rescuer fatigue was observed in the AHA 2010 group. In addition, the female in the AHA 2010 group could perform the compression rate required by the guidelines, however, significantly shallower compression depth and greater rescuer fatigue were observed when compared to the male. CONCLUSIONS: The quality of chest compressions was significantly improved following the 2010 AHA guidelines, however, it's more difficult for the rescuer to meet the guidelines due to the increased fatigue of rescuer.

Evaluating team-based, lecture-based, and hybrid learning methods for neurology clerkship in China: a method-comparison study.

BACKGROUND: Neurology is complex, abstract, and difficult for students to learn. However, a good learning method for neurology clerkship training is required to help students quickly develop strong clinical thinking as well as problem-solving skills. Both the traditional lecture-based learning (LBL) and the relatively new team-based learning (TBL) methods have inherent strengths and weaknesses when applied to neurology clerkship education. However, the strengths of each method may complement the weaknesses of the other. Combining TBL with LBL may produce better learning outcomes than TBL or LBL alone. We propose a hybrid method (TBL + LBL) and designed an experiment to compare the learning outcomes with those of pure LBL and pure TBL. METHODS: One hundred twenty-seven fourth-year medical students attended a two-week neurology clerkship program organized by the Department of Neurology, Sun Yat-Sen Memorial Hospital. All of the students were from Grade 2007, Department of Clinical Medicine, Zhongshan School of Medicine, Sun Yat-Sen University. These students were assigned to one of three groups randomly: Group A (TBL + LBL, with 41 students), Group B (LBL, with 43 students), and Group C (TBL, with 43 students). The learning outcomes were evaluated by a questionnaire and two tests covering basic knowledge of neurology and clinical practice. RESULTS: The practice test scores of Group A were similar to those of Group B, but significantly higher than those of Group C. The theoretical test scores and the total scores of Group A were significantly higher than those of Groups B and C. In addition, 100% of the students in Group A were satisfied with the combination of TBL + LBL. CONCLUSIONS: Our results support our proposal that the combination of TBL + LBL is acceptable to students and produces better learning outcomes than either method alone in neurology clerkships. In addition, the proposed hybrid method may also be suited for other medical clerkships that require students to absorb a large amount of abstract and complex course materials in a short period, such as pediatrics and internal medicine clerkships.

Continuance intention and digital health resources from the perspective of elaboration likelihood model and DART model: a structural equation modeling analysis.

Background: Internet hospitals, online health communities, and other digital health APPs have brought many changes to people's lives. However, digital health resources are experiencing low continuance intention due to many factors, including information security, service quality, and personal characteristics of users. Methods: We used cross-sectional surveys and structural equation modeling analysis to explore factors influencing user willingness to continue using digital health resources. Results: Information quality (ß = 0.31, p < 0.05), service quality (ß = 0.19, p < 0.05), platform reputation (ß = 0.34, p < 0.05), and emotional support (ß = 0.23, p < 0.05) have significant positive effects on user value co-creation behavior. Additionally, user trust and perceived usefulness could mediate the association between user value co-creation behavior and continuance intention, with mediation effects of 0.143 and 0.125, respectively. User involvement can positively moderate the association between user value co-creation behavior and user trust (ß = 0.151, t = 2.480, p < 0.001). Also, user involvement can positively moderate the association between value co-creation behavior and perceived usefulness (ß = 0.103, t = 3.377, p < 0.001). Conclusion: The keys to solving the problem of low continuance intention are improving the quality and service level of digital health resources, and promoting users' value co-creation behavior. Meanwhile, enterprises should build a good reputation, create a positive communication atmosphere in the community, and enhance user participation and sense of belonging.

Beneficial effects of ulinastatin on gut barrier function in sepsis.

BACKGROUND & OBJECTIVES: The gut contains some endogenous and exogenous microorganisms that can become potential pathogens of sepsis under certain circumstances. Therefore, the integrity and normal function of gut barrier is important for preventing the development of sepsis. The present study was designed to assess the effects of ulinastatin, a urinary trypsin inhibitor on gut barrier function and mortality in experimental sepsis. METHODS: Male Sprague-Dawley rats were subjected to ceacal ligation and puncture (CLP) or sham procedure. Rats were then treated with ulinastatin 50,000 U/kg/day or saline. The mortality rate was determined. Histology, apoptosis assays, and PCR were performed using ileum specimens at 3, 6, and 12 h following CLP. Serum levels of tumour necrosis factor α (TNF-α) and interleukin-6 (IL-6) were also measured at 0, 3, 6, and 12 h following CLP. RESULTS: Compared with the saline-treated CLP rats, the ulinastatin CLP rats had significantly increased survival time (P<0.05), lower histopathological scores of intestinal injury (P<0.05), reduced apoptosis detected by terminal deoxynucleotidyl transferase dUTP nick end labelling assay and caspase 3 activity (P<0.01). Moreover, RD-5 mRNA expression was significantly higher in ulinastatin-treated CLP animals than saline controls (P<0.05). These results suggested a preserved integrity and function of the gut barrier. Significantly lower plasma TNFα and IL-6 levels were detected in CLP rats with ulinastatin treatment, which contributed to increased survival time. INTERPRETATION & CONCLUSIONS: Our results suggest that ulinastatin has a therapeutic potential to prevent gut barrier dysfunction in the early stage of sepsis, thereby improving the outcome of sepsis. Further studies need to be done to understand the mechanism of action of ulinastatin.

Social integration, physical and mental health and subjective well-being in the floating population-a moderated mediation analysis.

Background: Individuals of domestic migrant populations in China (specifically, migration that is economically driven) often face difficulties in social integration. They are suffering from discrimination and unfair treatment in work and life, which do harm to their physical/mental health and Subjective Well-Being (SWB). Methods: The current study utilized a stratified sampling survey in the Yangtze River Delta region of China, in October and November 2022. Six hundred and eleven useful self-reported questionnaires were collected. Questionnaires include questions about social integration, social capital, physical/mental health, and SWB; Bootstrapping method was used to test the mediating effect of physical health and mental health. Multiple hierarchical regression was used to test the moderating effect of social capital. Results: Social integration had positive impact on the SWB (r = 0.523, p < 0.01). Bootstrap analysis showed that physical health and mental health partially mediated the correlation between social integration and SWB of Floating Population with a mediation effect of 0.149 and 0.192. Social capital can positively moderate the relationship between two pair of variables: social integration and SWB (ß = 0.152, t = 4.42, p < 0.001), physical health and SWB (ß = 0.148, t = 4.39, p < 0.01). However, social capital does not play a significant moderating role in the association between the effect of mental health on SWB (ß = 0.032, t = 0.973, p > 0.05). Conclusion: This study proved a significant correlation between social integration and SWB of Floating Population, with physical/mental health playing a mediating role. Enhancing the social integration of floating population and keeping healthy physically and mentally are key to improving their SWB.

HEART RATE VARIABILITY PARAMETERS WERE NOT ASSOCIATED WITH 30-DAY ALL-CAUSE MORTALITY IN INTENSIVE CARE UNIT PATIENTS WITH OR WITHOUT ATRIAL FIBRILLATION: A RETROSPECTIVE STUDY OF THE MIMIC-IV DATABASE.

ABSTRACT: Objective: Our study aims to evaluate the association between heart rate variability (HRV) and short- and long-term prognosis in patients admitted to intensive care unit (ICU). Methods and Results: Adult patients continuously monitored for over 24 h in ICUs from the the American Medical Information Mart for Intensive Care (MIMIC)-IV Waveform Database were recruited in our study. Twenty HRV-related variables (8 time domain, 6 frequency domain, and 6 nonlinear variables) were calculated based on RR intervals. The association between HRV and all-cause mortality was assessed. Ninety-three patients met the inclusion criteria and were classified into atrial fibrillation (AF) and sinus rhythm (SR) groups, which were further divided into 30-day survivor group and nonsurvivor\groups based on their survival status. The 30-day all-cause mortality rates in AF and SR groups were 36.3% and 14.6%, respectively. All the time domain, frequency domain, and nonlinear HRV parameters did not differ significantly between survivors and nonsurvivors with or without AF (all P > 0.05). Presence of renal failure, malignancy, and elevated blood urea nitrogen level were associated with increased 30-day all-cause mortality in SR patients, while presence of sepsis, infection, higher platelet count, and magnesium level were associated with increased 30-day all-cause mortality in AF patients. Conclusions: Heart rate variability variables were not associated with increased 30-day all-cause mortality in ICU patients with or without AF.

Curcumin Improves Cardiopulmonary Resuscitation Outcomes by Modulating Mitochondrial Metabolism and Apoptosis in a Rat Model of Cardiac Arrest.

Background: Curcumin, a diarylheptanoid chemical compound extracted from curcuma longa, exerts a variety of biological and pharmacological effects in numerous pathological conditions, including ischemia/reperfusion (I/R) injury. In this study, we investigated its role in post-resuscitation myocardial dysfunction in a rat model of cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) by targeting on mitochondrial metabolism and apoptosis. Methods: Animals were randomized into three groups: sham, control and curcumin, with fifteen rats in each group. Ventricular fibrillation (VF) was induced in the rats of the control and curcumin groups. The rats in the two groups were untreated for 8 min, followed by CPR for 8 min. Placebo (saline) or curcumin was administered by intraperitoneal injection, respectively, 5 min after successful resuscitation. Myocardial function was measured at baseline and post-resuscitation for 6 h consecutively. Ten rats in each group were closely observed for an additional 66 h to analyze the survival status, and the remaining five were sacrificed for the measurement of mitochondrial parameters and cell apoptosis. Results: Compared with the control group, myocardial function was significantly enhanced in the curcumin group, contributing to a better survival status. Curcumin treatment mitigated the depletion of superoxide dismutase (SOD) and the production of malondialdehyde (MDA). The structural damage of mitochondria was also alleviated, with improved conditions of mPTP and ΔΨm. Curcumin boosted the production of ATP and attenuated myocardial apoptosis. Cytochrome C, caspase-3 and its cleavage were suppressed by curcumin. Proteins closely related to the functional performance of mitochondria, including uncoupling protein 2 (UCP2) and uncoupling protein 3 (UCP3) were downregulated, while mitochondrial transcription factor A (mtTFA) was upregulated. Conclusion: Curcumin improves the outcomes of CPR via alleviating myocardial dysfunction induced by I/R injury. It exhibits anti-oxidation properties. Moreover, it is capable of ameliorating mitochondrial structure and energy metabolism, as well as inhibiting the mitochondrial apoptosis pathway. UCP2, UCP3, and mtTFA might also be involved in curcumin mediated protective effects on mitochondria.

[Relationship between carbon dioxide combining power and the short-term prognosis in acute ischemic stroke patients after thrombolysis].

OBJECTIVE: To investigate the effect of venous blood carbon dioxide binding capacity (CO2-CP) on the short-term prognosis of patients with acute ischemic stroke (AIS) after thrombolytic therapy. METHODS: A total of 86 AIS inpatients who received thrombolytic therapy in the emergency department of Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University from April 2019 to May 2021 were analyzed retrospectively. According to the venous blood CO2-CP levels at admission, the patients were divided into two groups: low CO2-CP group (CO2-CP < 23 mmol/L, n = 52) and high CO2-CP group (CO2-CP ≥ 23 mmol/L, n = 34). The CO2-CP levels and changes between the two groups before and after thrombolytic therapy were compared. The National Institutes of Health Stroke scale (NIHSS) score was used to evaluate the improvement rate of patients after thrombolytic therapy [NIHSS score at admission-NIHSS score at discharge)/NIHSS score at admission ×100%] and in-hospital death was also recorded. The correlation between CO2-CP levels and prognosis of patients with AIS during emergency visit was analyzed, the receiver operator characteristic curve (ROC curve) was drawn and the area under the ROC curve (AUC) was calculated to evaluate the predictive value of CO2-CP in the prognosis of AIS patients. RESULTS: The CO2-CP levels of low CO2-CP group and high CO2-CP group after thrombolytic therapy were significantly higher than those before treatment (mmol/L: 23.08±2.34 vs. 20.46±1.51, 25.24±2.16 vs. 23.94±1.07, both P < 0.05). The differences of CO2-CP before and after treatment in low CO2-CP group were significantly higher than those in high CO2-CP group (mmol/L: 2.62±0.83 vs. 1.30±1.09, P < 0.05). The improvement rate of CO2-CP levels in the high CO2-CP group (NIHSS improvement rate > 45%) was significantly higher than that in the low CO2-CP group [85.29% (29/34) vs. 23.08% (12/52)], while the mortality in the low CO2-CP group was significantly higher than that in the high CO2-CP group [11.54% (6/52) vs. 0% (0/34), P < 0.05]. The AUC of CO2-CP for the prognosis of patients with AIS thrombolysis was 0.820, the 95% confidence interval (95%CI) was 0.727-0.924, P = 0.000 1. CONCLUSION: AIS patients with CO2-CP levels less than 23 mmol/L have a poor short-term prognosis, which has certain predictive and clinical reference value for choosing thrombolytic time in emergency stroke patients.

Changes of Key Rate-Limiting Enzyme Activity in Glucose Metabolism After Cardiopulmonary Resuscitation.

OBJECTIVES: To investigate the activity of key rate-limiting enzymes of glucose metabolism after restoration of spontaneous circulation (ROSC), to explore the potential pathophysiological mechanism of impaired myocardial energy metabolism after cardiopulmonary resuscitation (CPR). METHODS: Twenty-one male Sprague-Dawley rats were randomized into three experimental groups assigned in accordance with different observation times after ROSC: Sham, instrumented rats without induced cardiac arrest or resuscitation; post-resuscitation (PR2 h); PR24 h. In these groups, CPR, including precordial compressions and synchronized mechanical ventilation, was initiated 6 min after asphyxia-induced cardiac arrest. Hearts were harvested after ROSC and samples were used to detect high-energy phosphate and glucose metabolic enzyme activity. RESULTS: Compared with sham, the contents of phosphocreatine and adenosine triphosphate reduced in the PR2 h group, while remained unchanged in the PR24 h group. Activities of hexokinase and pyruvate kinase did not change after ROSC. Phosphofructokinase activity decreased only in the PR24 h group. Activities of pyruvate dehydrogenase and citrate synthase fell in PR2 h group and recovered in the PR24 h group. However, isocitrate dehydrogenase and α-ketoglutarate dehydrogenase activities fell in the PR2 h group, but did not recover in the PR24 h group. CONCLUSIONS: Lowered key rate-limiting enzymes activity in glucose metabolism resulted in impairment of energy production in the early stage of ROSC, but partially recovered in 24 h. This process has a role in the mechanism of impaired myocardial energy metabolism after CPR. This investigation might shed light on new strategies to treat post resuscitation myocardial dysfunction.

Ketone Body Improves Neurological Outcomes after Cardiac Arrest by Inhibiting Mitochondrial Fission in Rats.

Ketone bodies including ß-hydroxybutyrate (ß-HB) have been proved the therapeutic potential in diverse neurological disorders. However, the role of ß-HB in the regulation of neurological injury after cardiac arrest (CA) remains unclear. We investigated the effect of ß-HB on brain mitochondrial dysfunction and neurological function after CA. A rat model of CA was established by asphyxia. The rats were randomly divided into three groups: sham group, control group, and ß-HB group. Animals received 200 mg/kg ß-HB or same volume vehicle at 10 minutes after return of spontaneous circulation by intraperitoneal injection. Neurological function was evaluated by neurologic deficit score and Y-maze. Neuronal cell loss and apoptosis were detected through hematoxylin-eosin staining, Nissl staining, and TdT-mediated dUTP nick-end labeling assay. Oxidative stress levels were determined by immunohistochemical staining of 4-hydoxynonenal and 8-hydroxy-2'-deoxyguanosine. Furthermore, mitochondrial ultrastructure of brain cells was observed by transmission electron microscopy. In addition, the protein expression levels of Bak, caspase 3, gasdermin D, caspase 1, brain-derived neurotrophic factor, dynamin-related protein 1 (Drp1), and phospho-Drp1 (ser616) were measured. We found that neurological function and survival rate were significantly higher in the ß-HB group compared with the control group. ß-HB also reduced neurons death and neurological oxidative stress after CA. Moreover, ß-HB reduced neurological injury from apoptosis and pyroptosis after CA. In addition, ß-HB maintained the structural integrity of brain mitochondria, prevented mitochondrial fission, and increased brain energy metabolism after CA. In conclusion, ß-HB beneficially affected the neurological function of rats after global cerebral ischemia, associated with decreased mitochondrial fission, and improved mitochondrial function. Our results suggest that ß-HB might benefit patients suffering from neurological dysfunction after CA.

[The epidemiological characteristic of 97,823 cases of pre-hospital medical care in Guangzhou city].

OBJECTIVE: To investigate the epidemiological information of patients in pre-hospital medical care in Guangzhou city, and to explore the characteristics of the patients. METHODS: The data in the year of 2008 were retrieved from the computer database of Guangzhou Emergency Medical Rescue Command Center. RESULTS: (1)In a total of 969 410 calls received, the time of distribution was found to be mainly between 16:00 and 18:00 [11.78% (114 224)], and least frequently between 04:00 and 06:00 [2.40% (23 237)]. (2)Among 109 682 dispatches of ambulances, Baiyun district received the most [26.77% (29 364)], and followed by Haizhu district [18.30% (20 069)], Tianhe district [18.20% (19 962)], respectively. (3)Among 97 823 cases of pre-hospital medical care, death rate of the male patients was higher than the female [amount: 57.65% (56 394) vs. 38.48% (37 641), mortality: 59.17% (3 269) vs. 33.95% (1 876)]. (4)In 9 7823 cases of pre-hospital medical care, trauma constituted the highest rate [34.57% (33 820)], especially traffic accidents [11.56% (11 307)], and the age of most of the patients ranged between 21 and 50. Disease of the nervous system ranged the second, followed by diseases of circulatory system, respiratory system and digestive system, and most of them were over 51 years old, and most frequently above 70. (5)In 97 823 cases of pre-hospital medical care, there were 5 525 deaths (5.65%), in whom the circulatory system diseases ranged first (especially sudden death) [33.07% (1 827)], followed by unclassified diseases [29.79% (1 646)], trauma [15.67% (866)], respiratory diseases [7.48% (413)], and neurological emergency illnesses [5.95% (329)]. The age of deceased was far older than 51, particularly 70. The age of most of the deceased was above 61, and age of traumatic death was 21-40. CONCLUSION: (1) It is very important to reduce the death rate of the middle-old aged patients by strengthening prevention and timely treatment of cardiovascular and cerebrovascular diseases, and improve the medical strategies in emergency care, in order to lower the death rate during emergency.(2)It is very important to emphasize safely in production lines and to strengthen traffic regulations in order to reduce the incidence of trauma, thus it is especially traffic accident, expect that the death rate of trauma could be lowered.

LncRNAs Participate in Post-Resuscitation Myocardial Dysfunction Through the PI3K/Akt Signaling Pathway in a Rat Model of Cardiac Arrest and Cardiopulmonary Resuscitation.

In this study, we aimed to explore the role of lncRNAs in post-resuscitation myocardial dysfunction in a rat model of CA-CPR. A rat model of CA-CPR was constructed using a VF method. Myocardial functions, including cardiac output (CO), ejection fraction (EF), and myocardial performance index (MPI), were evaluated at the baseline, and 1, 2, 3, 4, and 6 h after resuscitation. A high throughput sequencing method was used to screen the differentially expressed lncRNAs, miRNAs, and mRNAs, which were further analyzed with bioinformatics. In addition, relationships between the molecules involved in the PI3K/Akt signaling pathway were explored with ceRNA network. Compared with the sham group, EF was significantly reduced and MPI was increased at the five consecutive time points in the CA-CPR group. 68 lncRNAs were upregulated and 40 lncRNAs were downregulated in the CA-CPR group, while 30 miRNAs were downregulated and 19 miRNAs were upregulated. Moreover, mRNAs were also differentially expressed, with 676 upregulated and 588 downregulated. GO analysis suggested that genes associated with cell proliferation, cell death and programmed cell death were significantly enriched. KEGG analysis showed that the PI3K/Akt, MAPK and Ras signaling pathways were the three most-enriched pathways. Construction of a ceRNA regulatory network indicated that LOC102549506, LOC103689920, and LOC103690137 might play important roles in the regulation of the PI3K/Akt signaling pathway in the CA-CPR treated rat. Taken together, LncRNAs, including LOC102549506, LOC103689920 and LOC103690137, might participate in post-resuscitation myocardial dysfunction by functioning as ceRNAs and regulating the PI3K/Akt signaling pathway.

Sodium-Glucose Co-Transporter 2 Inhibition With Empagliflozin Improves Cardiac Function After Cardiac Arrest in Rats by Enhancing Mitochondrial Energy Metabolism.

Empagliflozin is a newly developed antidiabetic drug to reduce hyperglycaemia by highly selective inhibition of sodium-glucose co-transporter 2. Hyperglycaemia is commonly seen in patients after cardiac arrest (CA) and is associated with worse outcomes. In this study, we examined the effects of empagliflozin on cardiac function in rats with myocardial dysfunction after CA. Non-diabetic male Sprague-Dawley rats underwent ventricular fibrillation to induce CA, or sham surgery. Rats received 10 mg/kg of empagliflozin or vehicle at 10 min after return of spontaneous circulation by intraperitoneal injection. Cardiac function was assessed by echocardiography, histological analysis, molecular markers of myocardial injury, oxidative stress, mitochondrial ultrastructural integrity and metabolism. We found that empagliflozin did not influence heart rate and blood pressure, but left ventricular function and survival time were significantly higher in the empagliflozin treated group compared to the group treated with vehicle. Empagliflozin also reduced myocardial fibrosis, serum cardiac troponin I levels and myocardial oxidative stress after CA. Moreover, empagliflozin maintained the structural integrity of myocardial mitochondria and increased mitochondrial activity after CA. In addition, empagliflozin increased circulating and myocardial ketone levels as well as heart ß-hydroxy butyrate dehydrogenase 1 protein expression. Together, these metabolic changes were associated with an increase in cardiac energy metabolism. Therefore, empagliflozin favorably affected cardiac function in non-diabetic rats with acute myocardial dysfunction after CA, associated with reducing glucose levels and increasing ketone body oxidized metabolism. Our data suggest that empagliflozin might benefit patients with myocardial dysfunction after CA.

Compression depth of 30 mm has similar efficacy and fewer complications versus 50 mm during mechanical chest compression with miniaturized chest compressor in a porcine model of cardiac arrest.

BACKGROUND: Current guidelines recommend a 50 mm or greater compression depth for manual chest compression in adults. However, whether this uniform compression depth is a suitable requirement for mechanical CPR remains to be determined. We hypothesized that a relatively shallow compression depth (30 mm) would have similar hemodynamic efficacy but fewer complications versus the standard compression depth (50 mm) during mechanical cardiopulmonary resuscitation (CPR) with the miniaturized chest compressor (MCC) in a porcine model. METHODS: In the current study, we used a total of 16 domestic male pigs (38±2 kg). All pigs were exposed to 7 min of ventricular fibrillation (VF) followed by 5 min of CPR. Then the animals were randomly assigned to the shallow (30 mm) group and the standard (50 mm) group. At the second min of CPR, every pig was given epinephrine (20 µg/kg) through the femoral vein and repeated every 3 min. First defibrillation was delivered with a single 120 J shock at 5 min of CPR. Hemodynamics, carotid blood flow (CBF), end-tidal carbon dioxide (ETCO2), coronary perfusion pressure (CPP), intrathoracic pressure (ITP) and arterial blood gas were measured. Rib fractures and lung injuries, as indicated by ground-glass opacification (GGO), as well as intense parenchymal opacification (IPO), were assessed and calculated by quantitative computed tomography (QCT) scan. RESULTS: We found no significant differences in CPP, CBF, or ETCO2 between the both groups throughout the CPR period. After administration of epinephrine, the CPP of all animals increased while ETCO2 and CBF decreased during CPR. A significantly lower intrathoracic positive pressure (ITPP) and systolic artery pressure (SAP) were measured in the shallow group at the first min of CPR. However, we didn't find remarkable differences in these values between the both groups for the next 4 min of CPR. All animals were successfully resuscitated. The shallow group had significantly lower IPO QCT scores compared with the standard group. We found no significant differences in GGO QCT scores after resuscitation between both groups. CONCLUSIONS: Relatively shallow compression depth has similar hemodynamic efficacy but fewer complications versus the standard compression depth.