Pathological Characteristics and Classification of Unstable Coronary Atherosclerotic Plaques.

Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart disease, such as acute or chronic myocardial ischemic changes, sometimes make it difficult to locate the ischemic site due to the short death process, the lack of tissue reaction time. In some cases, the deceased died of sudden death on the first-episode, resulting in difficulty for medical examiners to make an accurate diagnosis. However, clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process. This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medical research, including plaque rupture, plaque erosion and calcified nodules, as well as the influencing factors leading to plaque instability, and briefly describes the research progress and technique of the atherosclerotic plaques, in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different pathologic states of coronary atherosclerotic plaques.

Survey on the Construction Status of Forensic Virtual Autopsy Laboratory and the Applicability of Laboratory Accreditation.

OBJECTIVES: To survey the development status and actual needs of virtual autopsy technology in China and to clarify the applicability of forensic virtual autopsy laboratory accreditation. METHODS: The questionnaire was set up included three aspects：(1) the current status of virtual autopsy technology development; (2) the accreditation elements such as personnel, equipment, entrustment and acceptance, methods, environmental facilities; (3) the needs and suggestions of practicing institutions. A total of 130 forensic pathology institutions were surveyed by online participation through the Questionnaire Star platform. RESULTS: Among the 130 institutions, 43.08% were familiar with the characteristics of virtual autopsy technology, 35.38% conducted or received training in virtual autopsy, and 70.77% have establishment needs (including maintenance). Relevant elements were suitable for laboratory accreditation. CONCLUSIONS: Virtual autopsy identification has gained social recognition. There is a demand for accreditation of forensic virtual autopsy laboratory. After the preliminary assessment, considering the characteristics and current situation of this technology, China National Accreditation Service for Conformity Assessment (CNAS) can first carry out the accreditation pilot of virtual autopsy project at large comprehensive forensic institutions with higher identification capability, and then CNAS can popularize the accreditation in a wide range when the conditions are suitable.

E-cigarette exposure with or without heating the e-liquid induces differential remodeling in the lungs and right heart of mice.

Various cardiopulmonary pathologies associated with electronic cigarette (EC) vaping have been reported. This study investigated the differential adverse effects of heating-associated by-products versus the intact components of EC aerosol to the lungs and heart of mice. We further dissected the roles of caspase recruitment domain-containing protein 9 (CARD9)-associated innate immune response and NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome in EC exposure-induced cardiopulmonary injury. C57BL/6 wild type (WT), CARD9-/-, and NLRP3-/- mice were exposed to EC aerosol 3 h/day, 5 days/week for 6 month with or without heating the e-liquid with exposure to ambient air as the control. In WT mice, EC exposure with heating (EwH) significantly increased right ventricle (RV) free wall thickness at systole and diastole. However, EC exposure without heating (EwoH) caused a significant decrease in the wall thickness at systole. RV fractional shortening was also markedly reduced following EwH in WT and NLRP3-/- mice. Further, EwH activated NF-κB and p38 MAPK inflammatory signaling in the lungs, but not in the RV, in a CARD9- and NLRP3-dependent manner. Levels of circulatory inflammatory mediators were also elevated following EwH, indicating systemic inflammation. Moreover, EwoH activated TGF-ß1/SMAD2/3/α-SMA fibrosis signaling in the lungs but not the RV of WT mice. In conclusion, EC aerosol exposure following EwH or EwoH induced differential cardiopulmonary remodeling and CARD9 innate immune response and NLRP3 inflammasome contributed to the adverse effects.

Dysregulated lipolysis and lipophagy in lipid droplets of macrophages from high fat diet-fed obese mice.

Obesity is associated with lipid droplet (LD) accumulation, dysregulated lipolysis and chronic inflammation. Previously, the caspase recruitment domain-containing protein 9 (CARD9) has been identified as a potential contributor to obesity-associated abnormalities including cardiac dysfunction. In the current study, we explored a positive feedback signalling cycle of dysregulated lipolysis, CARD9-associated inflammation, impaired lipophagy and excessive LD accumulation in sustaining the chronic inflammation associated with obesity. C57BL/6 WT and CARD9-/- mice were fed with normal diet (ND, 12% fat) or a high fat diet (HFD, 45% fat) for 5 months. Staining of LDs from peritoneal macrophages (PMs) revealed a significant increase in the number of cells with LD and the number of LD per cell in the HFD-fed WT but not CARD9-/- obese mice. Rather, CARD9 KO significantly increased the mean LD size. WT obese mice showed down regulation of lipolytic proteins with increased diacylglycerol (DAG) content, and CARD9 KO normalized DAG with restored lipolytic protein expression. The build-up of DAG in the WT obese mice is further associated with activation of PKCδ, NF-κB and p38 MAPK inflammatory signalling in a CARDD9-dependent manner. Inhibition of adipose triglyceride lipase (ATGL) by Atglistatin (Atg) resulted in similar effects as in CARD9-/- mice. Interestingly, CARD9 KO and Atg treatment enhanced lipophagy. In conclusion, HFD feeding likely initiated a positive feedback signalling loop from dysregulated lipolysis, CARD9-dependent inflammation, impaired lipophagy, to excessive LD accumulation and sustained inflammation. CARD9 KO and Atg treatment protected against the chronic inflammation by interrupting this feedforward cycle.

Fast and accurate measurement of the polarization-dependent detection efficiency of superconducting nanowire single photon detectors.

Superconducting nanowire single photon detectors (SNSPDs) have been extensively investigated due to their superior characteristics, including high system detection efficiency, low dark count rate and short recovery time. The polarization sensitivity introduced by the meandering-type superconductor nanowires is an intrinsic property of SNSPD, which is normally measured by sweeping hundreds of points on the Poincaré sphere to overcome the unknown birefringent problem of the SNSPD's delivery fiber. In this paper, we propose an alternative method to characterize the optical absorptance of SNSPDs, without sweeping hundreds of points on the Poincaré sphere. It is shown theoretically that measurements on the system detection efficiencies (SDEs) subject to cases of four specific photon polarization states are sufficient to reveal the two eigen-absorptances of the SNSPD. We validate the proposed method by comparing the measured detection spectra with the spectra attained from sweeping points on the Poincaré sphere and the simulated absorption spectra.

[Evaluation of brain injury caused by stick type blunt instruments based on convolutional neural network and finite element method].

The finite element method is a new method to study the mechanism of brain injury caused by blunt instruments. But it is not easy to be applied because of its technology barrier of time-consuming and strong professionalism. In this study, a rapid and quantitative evaluation method was investigated to analyze the craniocerebral injury induced by blunt sticks based on convolutional neural network and finite element method. The velocity curve of stick struck and the maximum principal strain of brain tissue (cerebrum, corpus callosum, cerebellum and brainstem) from the finite element simulation were used as the input and output parameters of the convolutional neural network The convolutional neural network was trained and optimized by using the 10-fold cross-validation method. The Mean Absolute Error (MAE), Mean Square Error (MSE), and Goodness of Fit ( R 2) of the finally selected convolutional neural network model for the prediction of the maximum principal strain of the cerebrum were 0.084, 0.014, and 0.92, respectively. The predicted results of the maximum principal strain of the corpus callosum were 0.062, 0.007, 0.90, respectively. The predicted results of the maximum principal strain of the cerebellum and brainstem were 0.075, 0.011, and 0.94, respectively. These results show that the research and development of the deep convolutional neural network can quickly and accurately assess the local brain injury caused by the sticks blow, and have important application value for understanding the quantitative evaluation and the brain injury caused by the sticks struck. At the same time, this technology improves the computational efficiency and can provide a basis reference for transforming the current acceleration-based brain injury research into a focus on local brain injury research.

Strike Velocity Prediction of Stick Blunt Instruments Based on Backpropagation Neural Network.

OBJECTIVES: To analyze and predict the striking velocity range of stick blunt instruments in different populations, and to provide basic data for the biomechanical analysis of blunt force injuries in forensic identification. METHODS: Based on the Photron FASTCAM SA3 high-speed camera, Photron FASTCAM Viewer 4.0 and SPSS 26.0 software, the tester's maximum striking velocity of stick blunt instruments and related factors were calculated and analyzed, and inputed to the backpropagation (BP) neural network for training. The trained and verified BP neural network was used as the prediction model. RESULTS: A total of 180 cases were tested and 470 pieces of data were measured. The maximum striking velocity range was 11.30-35.99 m/s. Among them, there were 122 female data, the maximum striking velocity range was 11.63-29.14 m/s; there were 348 male data, the maximum striking velocity range was 20.11-35.99 m/s. The maximum striking velocity of stick blunt instruments increased with the increase of weight and height, but there was no obvious increase trend in the male group; the maximum striking velocity decreased with age, but there was no obvious downward trend in the female group. The maximum striking velocity of stick blunt instruments has no significant correlation with the material and strike posture. The root mean square error (RMSE), the mean absolute error (MAE) and the coefficient of determination (R2) of the prediction results by using BP neural network were 2.16, 1.63 and 0.92, respectively. CONCLUSIONS: The prediction model of BP neural network can meet the demand of predicting the maximum striking velocity of different populations.

Reconstruction and Quantitative Evaluation of Blunt Injury Cases by Finite Element Method.

OBJECTIVES: To reconstruct the cases of acceleration craniocerebral injury caused by blunt in forensic cases by finite element method (FEM), and to study the biomechanical mechanism and quantitative evaluation method of blunt craniocerebral injury. METHODS: Based on the established and validated finite element head model of Chinese people, the finite element model of common injury tool was established with reference to practical cases in the forensic identification, and the blunt craniocerebral injury cases were reconstructed by simulation software. The cases were evaluated quantitatively by analyzing the biomechanical parameters such as intracranial pressure, von Mises stress and the maximum principal strain of brain tissue. RESULTS: In case 1, when the left temporal parietal was hit with a round wooden stick for the first time, the maximum intracranial pressure was 359 kPa; the maximum von Mises stress of brain tissue was 3.03 kPa at the left temporal parietal; the maximum principal strain of brain tissue was 0.016 at the left temporal parietal. When the right temporal was hit with a square wooden stick for the second time, the maximum intracranial pressure was 890 kPa; the maximum von Mises stress of brain tissue was 14.79 kPa at the bottom of right temporal lobe; the maximum principal strain of brain tissue was 0.103 at the bottom of the right temporal lobe. The linear fractures occurred at the right temporal parietal skull and the right middle cranial fossa. In case 2, when the forehead and left temporal parietal were hit with a round wooden stick, the maximum intracranial pressure was 370 kPa and 1 241 kPa respectively, the maximum von Mises stress of brain tissue was 3.66 kPa and 26.73 kPa respectively at the frontal lobe and left temporal parietal lobe, and the maximum principal strain of brain tissue was 0.021 and 0.116 respectively at the frontal lobe and left temporal parietal lobe. The linear fracture occurred at the left posterior skull of the coronary suture. The damage evaluation indicators of the simulation results of the two cases exceeded their damage threshold, and the predicted craniocerebral injury sites and fractures were basically consistent with the results of the autopsy. CONCLUSIONS: The FEM can quantitatively evaluate the degree of blunt craniocerebral injury. The FEM combined with traditional method will become a powerful tool in forensic craniocerebral injury identification and will also become an effective means to realize the visualization of forensic evidence in court.

Pathological changes induced by phosphine poisoning: a study on 8 children.

Aluminum phosphide (ALP) has been extensively used as an economical and effective insecticide, rodenticide, and fumigant. The active ingredient of ALP is phosphine (PH3), the use of which can lead to accidental inhalation and mass poisoning with high mortality. Exposure to PH3 will give rise to global damage in the human body. This study reviewed 4 fatal accidents including 8 children with PH3 poisoning and aimed to determine the pathological changes that resulted from exposure to PH3 and, secondly, aimed to determine whether oxidative stress was involved in PH3-induced neurotoxicity using histopathological and immunohistochemistry (IHC) methods. After focusing on the pathological changes on the major organs, we found severe damage induced by PH3 in many systems, especially the neurological system, including neuronal, axonal, and vascular injuries as well as oxidative damage with increased expression of 4-hydroxy-2-trans-nonenal (4HNE), 8-hydroxy-2'-deoxyguanosine (8-OH-dG), and 3-nitrotyrosine (3-NT) in the brain, which indicated that oxidative stress was a crucial mechanism for neuronal death in PH3 toxicity. Moreover, we observed severe myocardial and hepatocellular fatty degeneration in the tissues of the heart and liver. We considered that these characteristic changes are a suggestive sign of PH3 poisoning and partly explained the toxic mechanism of PH3 (inhibition of mitochondrial oxidative phosphorylation). We hope that this research could improve the understanding of the toxicity of PH3 in both forensic and clinical practice.

The essential function of CARD9 in diet-induced inflammation and metabolic disorders in mice.

Inflammation and metabolic disorder are common pathophysiological conditions, which play a vital role in the development of obesity and type 2 diabetes. The purpose of this study was to explore the effects of caspase recruitment domain (CARD) 9 in the high fat diet (HFD)-treated mice and attempt to find a molecular therapeutic target for obesity development and treatment. Sixteen male CARD9-/- and corresponding male WT mice were fed with normal diet or high fat diet, respectively, for 12 weeks. Glucose tolerance, insulin resistance, oxygen consumption and heat production of the mice were detected. The CARD9/MAPK pathway-related gene and protein were determined in insulin-responsive organs using Western blotting and quantitative PCR. The results showed that HFD-induced insulin resistance and impairment of glucose tolerance were more severe in WT mice than that in the CARD9-/- mice. CARD9 absence significantly modified O2 consumption, CO2 production and heat production. CARD9-/- mice displayed the lower expression of p38 MAPK, JNK and ERK when compared to the WT mice in both HFD- and ND-treated groups. HFD induced the increase of p38 MAPK, JNK and ERK in WT mice but not in the CARD9-/- mice. The results indicated that CARD9 absence could be a vital protective factor in diet-induced obesity via the CARD9/MAPK pathway, which may provide new insights into the development of gene knockout to improving diet-induced obesity and metabolism disorder.

CARD9 knockout ameliorates myocardial dysfunction associated with high fat diet-induced obesity.

Obesity is associated with chronic inflammation which plays a critical role in the development of cardiovascular dysfunction. Because the adaptor protein caspase recruitment domain-containing protein 9 (CARD9) in macrophages regulates innate immune responses via activation of pro-inflammatory cytokines, we hypothesize that CARD9 mediates the pro-inflammatory signaling associated with obesity en route to myocardial dysfunction. C57BL/6 wild-type (WT) and CARD9(-/-) mice were fed normal diet (ND, 12% fat) or a high fat diet (HFD, 45% fat) for 5months. At the end of 5-month HFD feeding, cardiac function was evaluated using echocardiography. Cardiomyocytes were isolated and contractile properties were measured. Immunofluorescence was performed to detect macrophage infiltration in the heart. Heart tissue homogenates, plasma, and supernatants from isolated macrophages were collected to measure the concentrations of pro-inflammatory cytokines using ELISA kits. Western immunoblotting analyses were performed on heart tissue homogenates and isolated macrophages to explore the underlying signaling mechanism(s). CARD9 knockout alleviated HFD-induced insulin resistance and glucose intolerance, prevented myocardial dysfunction with preserved cardiac fractional shortening and cardiomyocyte contractile properties. CARD9 knockout also significantly decreased the number of infiltrated macrophages in the heart with reduced myocardium-, plasma-, and macrophage-derived cytokines including IL-6, IL-1ß and TNFα. Finally, CARD9 knockout abrogated the increase of p38 MAPK phosphorylation, the decrease of LC3BII/LC3BI ratio and the up-regulation of p62 expression in the heart induced by HFD feeding and restored cardiac autophagy signaling. In conclusion, CARD9 knockout ameliorates myocardial dysfunction associated with HFD-induced obesity, potentially through reduction of macrophage infiltration, suppression of p38 MAPK phosphorylation, and preservation of autophagy in the heart.

Probucol Protects Endothelial Progenitor Cells Against Oxidized Low-Density Lipoprotein via Suppression of Reactive Oxygen Species Formation In Vivo.

BACKGROUND/AIMS: Oxidized low-density lipoprotein (ox-LDL) is a major component of hyperlipidemia and contributes to atherosclerosis. Endothelial progenitor cells (EPCs) play an important role in preventing atherosclerosis and notably decreased in hyperlipidemia. Ox-LDL and ox-LDL-related reactive oxygen species (ROS) have deleterious effects on EPCs. Probucol as an antioxidant and anti-inflammatory drug reduces ROS production. The present study was to determine if probucol could protect EPCs from ox-LDL in vivo and to investigate the potential mechanisms. METHODS: ox-LDL was injected into male C57BL/6 mice for 3 days with or without probucol treatment with PBS as control. Bone marrow (BM) fluid, serum, circulating mononuclear cells (MNCs) and EPCs were collected for analysis. RESULTS: the increased extracellular ROS in BM, serum and blood intracellular ROS production in the mice with ox-LDL treatment in association with a significant reduction of circulating MNCs and EPCs were restored with Probucol treatment. A significant increase in the serum ox-LDL and C-reactive protein and decrease in superoxide dismutase and circulating MNCs and EPCs were observed in hyperlipidemic patients that were effectively reversed with probucol treatment. CONCLUSION: these data suggested that probucol could protect EPCs from ox-LDL through inhibition of ROS production in vivo.

Three homicides with darts tainted with succinylcholine: autopsy and toxicology.

In emergency departments, intoxication with the muscle relaxant succinylcholine (SUX) often leads to a potentially lethal respiratory paralysis or other deleterious side effects. However, homicide cases with SUX poisoning are very rare because the toxic or lethal concentration ranges of SUX have not yet been determined. We described three uncommon homicide cases due to acute poisoning by darts contaminated with SUX. All the victims died quickly (less than 30 min) after being shot by an especially designed dart gun. Succinylmonocholine (SMC), a metabolite of SUX, was used as a marker to detect the latter. HPLC-MS/MS analysis demonstrated the presence of SUX in the droplet residues of the darts and SMC in the blood and urine in all cases. SMC concentrations of 0.45, 14.0, and 17.9 ng/ml were detected in the victims' blood and 259.0 ng/ml in the urine from the third case. The main pathological changes consisted of hemorrhage of the injured soft tissues, visceral congestion, severe pulmonary edema, and multifocal petechial hemorrhage of the heart and lungs. Taken together, the findings supported a diagnosis of fatal SUX poisoning. Futhermore, our study provided a reference for the lethal concentrations of SUX poisoning.

Cell membrane damage is involved in the impaired survival of bone marrow stem cells by oxidized low-density lipoprotein.

Cell therapy with bone marrow stem cells (BMSCs) remains a viable option for tissue repair and regeneration. A major challenge for cell therapy is the limited cell survival after implantation. This study was to investigate the effect of oxidized low-density lipoprotein (ox-LDL, naturally present in human blood) on BMSC injury and the effect of MG53, a tissue repair protein, for the improvement of stem cell survival. Rat bone marrow multipotent adult progenitor cells (MAPCs) were treated with ox-LDL, which caused significant cell death as reflected by the increased LDH release to the media. Exposure of MAPCs to ox-LDL led to entry of fluorescent dye FM1-43 measured under confocal microscope, suggesting damage to the plasma membrane. Ox-LDL also generated reactive oxygen species (ROS) as measured with electron paramagnetic resonance spectroscopy. While antioxidant N-acetylcysteine completely blocked ROS production from ox-LDL, it failed to prevent ox-LDL-induced cell death. When MAPCs were treated with the recombinant human MG53 protein (rhMG53) ox-LDL induced LDH release and FM1-43 dye entry were significantly reduced. In the presence of rhMG53, the MAPCs showed enhanced cell survival and proliferation. Our data suggest that membrane damage induced by ox-LDL contributed to the impaired survival of MAPCs. rhMG53 treatment protected MAPCs against membrane damage and enhanced their survival which might represent a novel means for improving efficacy for stem cell-based therapy for treatment of diseases, especially in setting of hyperlipidemia.

Compressed sensing of spatial electron paramagnetic resonance imaging.

PURPOSE: To improve image quality and reduce data requirements for spatial electron paramagnetic resonance imaging (EPRI) by developing a novel reconstruction approach using compressed sensing (CS). METHODS: EPRI is posed as an optimization problem, which is solved using regularized least-squares with sparsity promoting penalty terms, consisting of the l1 norms of the image itself and the total variation of the image. Pseudo-random sampling was employed to facilitate recovery of the sparse signal. The reconstruction was compared with the traditional filtered back-projection reconstruction for simulations, phantoms, isolated rat hearts, and mouse gastrointestinal (GI) tracts labeled with paramagnetic probes. RESULTS: A combination of pseudo-random sampling and CS was able to generate high-fidelity EPR images at high acceleration rates. For three-dimensional (3D) phantom imaging, CS-based EPRI showed little visual degradation at nine-fold acceleration. In rat heart datasets, CS-based EPRI produced high quality images with eight-fold acceleration. A high resolution mouse GI tract reconstruction demonstrated a visual improvement in spatial resolution and a doubling in signal-to-noise ratio (SNR). CONCLUSION: A novel 3D EPRI reconstruction using compressed sensing was developed and offers superior SNR and reduced artifacts from highly undersampled data.

All-Water Etching-Free Electron Beam Lithography for On-Chip Nanomaterials.

Electron beam lithography uses an accelerated electron beam to fabricate patterning on an electron-beam-sensitive resist but requires complex dry etching or lift-off processes to transfer the pattern to the substrate or film on the substrate. In this study, etching-free electron beam lithography is developed to directly write a pattern of various materials in all-water processes, achieving the desired semiconductor nanopatterns on a silicon wafer. Introduced sugars are copolymerized with metal ions-coordinated polyethylenimine under the action of electron beams. The all-water process and thermal treatment result in nanomaterials with satisfactory electronic properties, indicating that diverse on-chip semiconductors (e.g., metal oxides, sulfides, and nitrides) can be directly printed on-chip by an aqueous solution system. As a demonstration, zinc oxide patterns can be achieved with a line width of 18 nm and a mobility of 3.94 cm2 V-1 s-1. This etching-free electron beam lithography strategy provides an efficient alternative for micro/nanofabrication and chip manufacturing.

Sudden death due to cerebral leukemic hemorrhage occurring after acupuncture treatment for gingival bleeding.

A 45-year-old woman who experienced stomalgia and gingival bleeding for several days died unexpectedly after acupuncture treatment. At autopsy, trivial injuries on the liver and the stomach and mild hemoperitoneum due to improper acupuncture were found. Also,acute lymphoblastic leukemia and hyperleukocytosis were diagnosed by postmortem examinations. Intracranial hemorrhage due to undiagnosed acute lymphoblastic leukemia was identified as the cause of death.Moreover, the relationship between therapeutic misadventure and death was also determined. We suggest that undiagnosed leukemia should be considered as a differential diagnosis when sudden death occurs owing to intracranial hemorrhage. If therapeutic misadventure was involved,it is also of great importance to assess the relationship between that and death in forensic expertise.

Transgenic over expression of ectonucleotide triphosphate diphosphohydrolase-1 protects against murine myocardial ischemic injury.

Modulation of purinergic signaling is critical to myocardial homeostasis. Ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD-1; CD39) which converts the proinflammatory molecules ATP or ADP to AMP is a key regulator of purinergic modulation. However, the salutary effects of transgenic over expression of ENTPD-1 on myocardial response to ischemic injury have not been tested to date. Therefore we hypothesized that ENTPD-1 over expression affords myocardial protection from ischemia-reperfusion injury via specific cell signaling pathways. ENTPD-1 transgenic mice, which over express human ENTPDase-1, and wild-type (WT) littermates were subjected to either ex vivo or in vivo ischemia-reperfusion injury. Infarct size, inflammatory cell infiltrate and intracellular signaling molecule activation were evaluated. Infarct size was significantly reduced in ENTPD-1 versus WT hearts in both ex vivo and in vivo studies. Following ischemia-reperfusion injury, ENTPD-1 cardiac tissues demonstrated an increase in the phosphorylation of the cellular signaling molecule extracellular signal-regulated kinases 1/2 (ERK 1/2) and glycogen synthase kinase-3ß (GSK-3ß). Resistance to myocardial injury was abrogated by treatment with a non-selective adenosine receptor antagonist, 8-SPT or the more selective A(2B) adenosine receptor antagonist, MRS 1754, but not the A(1) selective antagonists, DPCPX. Additionally, treatment with the ERK 1/2 inhibitor PD98059 or the mitochondrial permeability transition pore opener, atractyloside, abrogated the cardiac protection provided by ENTPDase-1 expression. These results suggest that transgenic ENTPDase-1 expression preferentially conveys myocardial protection from ischemic injury via adenosine A(2B) receptor engagement and associated phosphorylation of the cellular protective signaling molecules, Akt, ERK 1/2 and GSK-3ß that prevents detrimental opening of the mitochondrial permeability transition pore.

Endothelial NOS activity and myocardial oxygen metabolism define the salvageable ischemic time window for ischemic postconditioning.

Ischemic postconditioning (IPOC) could be ineffective or even detrimental if the index ischemic duration is either too short or too long. The present study is to demonstrate that oxygen supply and metabolism defines a salvageable ischemic time window of IPOC in mice. C57BL/6 mice underwent coronary artery occlusion followed by reperfusion (I/R), with or without IPOC by three cycles of 10 s/10 s R/I. In vivo myocardial tissue oxygenation was monitored with electron paramagnetic resonance oximetry. Regional blood flow (RBF) was measured with a laser Doppler monitor. At the end of 60 min reperfusion, tissue from the risk area was collected, and mitochondrial enzyme activities were assayed. Tissue oximetry demonstrated that I/R induced a reperfusion hyperoxygenation state in the 30- and 45-min but not 15- and 60-min ischemia groups. IPOC attenuated the hyperoxygenation with 45 but not 30 min ischemia. RBF, eNOS phosphorylation, and mitochondrial enzyme activities were suppressed after I/R with different ischemic time, and IPOC afforded protection with 30 and 45 but not 60 min ischemia. Infarct size measurement indicated that IPOC reduced infarction with 30 and 45 min but not 60 min ischemia. Clearly, IPOC protected mouse heart with a defined ischemic time window between 30 and 45 min. This salvageable time window was accompanied by the improvement of RBF due to increased phosphorylated eNOS and the preservation of mitochondrial oxygen consumption due to conserved mitochondrial enzyme activities. Interestingly, this salvageable ischemic time window was mirrored by tissue hyperoxygenation status in the postischemic heart.

Exercise ameliorates high-fat diet-induced metabolic and vascular dysfunction, and increases adipocyte progenitor cell population in brown adipose tissue.

A high-fat diet (HFD) is associated with adipose inflammation, which contributes to key components of metabolic syndrome, including obesity and insulin resistance. The increased visceral adipose tissue mass associated with obesity is the result of hyperplasia and hypertrophy of adipocytes. To investigate the effects of exercise on HFD-induced metabolic disorders, male C57BL/6 mice were divided into four groups: SED (sedentary)-ND (normal diet), EX (exercise)-ND, SED-HFD, and EX-HFD. Exercise was performed on a motorized treadmill at 15 m/min, 40 min/day, and 5 day/wk for 8 wk. Exercise resulted in a decrease in abdominal fat contents and inflammation, improvements in glucose tolerance and insulin resistance, and enhancement of vascular constriction and relaxation responses. Exercise with or without HFD increased putative brown adipocyte progenitor cells in brown adipose tissue compared with groups with the same diet, with an increase in brown adipocyte-specific gene expression in brown and white adipose tissue. Exercise training enhanced in vitro differentiation of the preadipocytes from brown adipose depots into brown adipocytes and enhanced the expression of uncoupling protein 1. These findings suggest that exercise ameliorates high-fat diet-induced metabolic disorders and vascular dysfunction, and increases adipose progenitor cell population in brown adipose tissue, which might thereby contribute to enhanced functional brown adipose.