Acute Myocardial Infarction: Perspectives on Physiopathology of Myocardial Injury and Protective Interventions

Diffuse coronary artery injury produces a host of physiopathological, structural and metabolic changes in cardiocytes that, if not rectified, result in significant loss of functional myocardium to cause cardiac contractile dysfunction. Restoration of blood perfusion to the infarct-related artery helps to limit the acute effects of myocardial infarction; however, cardiocyte injury may be exacerbated because of the restoration of blood perfusion to the ischemic zone (i.e. reperfusion injury). Various manifestations of reperfusion injury include no-reflow, myocardial stunning or hibernation and ventricular arrhythmias. Consequently, reperfusion of an infarct related artery is often viewed in the context of being a “double-edged sword.” Pharmacologic and non-pharmacologic interventions have been investigated in pre-clinical and clinical studies in the hunt to develop strategies to protect cardiomyocytes against the long-term effects of ischemia, or delay development of necrosis (resulting from ischemia or reperfusion). This book chapter will update current thinking on cardioprotective strategies to improve clinical outcomes in patients with coronary artery disease

Autonomic Nervous System and Neurocardiac Physiopathology

The autonomic nervous system regulates multiple physiological functions; how distinct neurons in peripheral autonomic and intrathoracic ganglia communicate remains to be established. Increasing focus is being paid to functionality of the neurocardiac axis and crosstalk between the intrinsic nervous system and diverse organ systems. Current findings indicate that progression of cardiovascular disease comprises peripheral and central aspects of the cardiac nervous system hierarchy. Indeed, autonomic neuronal dysfunction is known to participate in arrhythmogenesis and sudden cardiac death; diverse interventions (pharmacological, non-pharmacological) that affect neuronal remodeling in the heart following injury caused by cardiovascular disease (congestive heart failure, etc.) or acute myocardial infarction are being investigated. Herein we examine recent findings from clinical and animal studies on the role of the intrinsic cardiac nervous system on regulation of myocardial perfusion and the consequences of cardiac injury. We also discuss different interventions that target the autonomic nervous system, stimulate neuronal remodeling and adaptation, and thereby optimize patient outcomes

Association of 1800 cGy cranial irradiation with intellectual function in children with acute lymphoblastic leukaemia

Cranial radiation therapy in childhood acute lymphoblastic leukaemia has been associated with adverse neuropsychological effects, such as low intelligence. However, records show that these associations usually occur when the dose of radiation used is 2400 cGy. We investigated whether a lower dose of 1800 cGy had the same adverse effects on long-term survivors and whether high doses of methotrexate but no radiation therapy would have a more beneficial effect. We evaluated 203 children for six years in a multi-centre European study. The patients were divided into two groups: 129 children treated with 1800 cGy of cranial radiation therapy and 74 children who received high-dose methotrexate but no radiation therapy. We used full scale intelligence quotient, verbal, and performance IQ tests to assess the patient's intelligence. We found a significant decline in full scale intelligence quotient in the irradiated group that increased with the length of time from diagnosis. Younger age at diagnosis was associated with lower full scale intelligence quotient in the radiated group. Our results indicate that a radiation dose of 1800 cGy can have negative effects on neurocognitive function and we continue to question the benefit of low-dose cranial radiation therapy

Body segment parameters of Paralympic athletes from dual-energy X-ray absorptiometry

The final publication is available at Springer via http://dx.doi.org/10.1007/s12283-016-0200-3This research represents the first documented investigation into the body segment parameters of Paralympic athletes (e.g., individuals with spinal cord injuries and lower extremity amputations). Two-dimensional body segment parameters (i.e., mass, length, position vector of the center of mass, and principal mass moment of inertia about the center of mass) were quantified from dual-energy X-ray absorptiometry (DXA). In addition to establishing a body segment parameter database of Paralympic athletes for prospective biomechanists and engineers, the mass of each body segment as experimentally measured via the DXA imaging was compared with that reported by previous research of able-bodied cadavers. In general, there were significant differences in the body segment masses between the different methods. These findings support the implementation of the proposed database for developing valid multibody biomechanical models of Paralympic athletes with distinct physical disabilities.This research was funded by Dr. John McPhee’s Tier I Canada Research Chair in Biomechatronic System Dynamics

Motivation and incentives of rural maternal and neonatal health care providers: a comparison of qualitative findings from Burkina Faso, Ghana and Tanzania.

In Burkina Faso, Ghana and Tanzania strong efforts are being made to improve the quality of maternal and neonatal health (MNH) care. However, progress is impeded by challenges, especially in the area of human resources. All three countries are striving not only to scale up the number of available health staff, but also to improve performance by raising skill levels and enhancing provider motivation. In-depth interviews were used to explore MNH provider views about motivation and incentives at primary care level in rural Burkina Faso, Ghana and Tanzania. Interviews were held with 25 MNH providers, 8 facility and district managers, and 2 policy-makers in each country. Across the three countries some differences were found in the reasons why people became health workers. Commitment to remaining a health worker was generally high. The readiness to remain at a rural facility was far less, although in all settings there were some providers that were willing to stay. In Burkina Faso it appeared to be particularly difficult to recruit female MNH providers to rural areas. There were indications that MNH providers in all the settings sometimes failed to treat their patients well. This was shown to be interlinked with differences in how the term 'motivation' was understood, and in the views held about remuneration and the status of rural health work. Job satisfaction was shown to be quite high, and was particularly linked to community appreciation. With some important exceptions, there was a strong level of agreement regarding the financial and non-financial incentives that were suggested by these providers, but there were clear country preferences as to whether incentives should be for individuals or teams. Understandings of the terms and concepts pertaining to motivation differed between the three countries. The findings from Burkina Faso underline the importance of gender-sensitive health workforce planning. The training that all levels of MNH providers receive in professional ethics, and the way this is reinforced in practice require closer attention. The differences in the findings across the three settings underscore the importance of in-depth country-level research to tailor the development of incentives schemes

Uncertainty-based Traffic Accident Anticipation with Spatio-Temporal Relational Learning

Traffic accident anticipation aims to predict accidents from dashcam videos as early as possible, which is critical to safety-guaranteed self-driving systems. With cluttered traffic scenes and limited visual cues, it is of great challenge to predict how long there will be an accident from early observed frames. Most existing approaches are developed to learn features of accident-relevant agents for accident anticipation, while ignoring the features of their spatial and temporal relations. Besides, current deterministic deep neural networks could be overconfident in false predictions, leading to high risk of traffic accidents caused by self-driving systems. In this paper, we propose an uncertainty-based accident anticipation model with spatio-temporal relational learning. It sequentially predicts the probability of traffic accident occurrence with dashcam videos. Specifically, we propose to take advantage of graph convolution and recurrent networks for relational feature learning, and leverage Bayesian neural networks to address the intrinsic variability of latent relational representations. The derived uncertainty-based ranking loss is found to significantly boost model performance by improving the quality of relational features. In addition, we collect a new Car Crash Dataset (CCD) for traffic accident anticipation which contains environmental attributes and accident reasons annotations. Experimental results on both public and the newly-compiled datasets show state-of-the-art performance of our model. Our code and CCD dataset are available at https://github.com/Cogito2012/UString.Comment: Accepted by ACM MM 202

Sex-related differences in oncologic outcomes, operative complications and health-related quality of life after curative-intent oesophageal cancer treatment: multicentre retrospective analysis

Background: Oesophageal cancer, in particular adenocarcinoma, has a strong male predominance. However, the impact of patient sex on operative and oncologic outcomes and recovery of health-related quality of life is poorly documented, and was the focus of this large multicentre cohort study. Methods: All consecutive patients who underwent oncological oesophagectomy from 2009 to 2015 in the 20 European iNvestigation of SUrveillance after Resection for Esophageal cancer study group centres were assessed. Clinicopathologic variables, therapeutic approach, postoperative complications, survival and health-related quality of life data were compared between male and female patients. Multivariable analyses adjusted for age, sex, tumour histology, treatment protocol and major complications. Specific subgroup analyses comparing adenocarcinoma versus squamous cell cancer for all key outcomes were performed. Results: Overall, 3974 patients were analysed, 3083 (77.6%) male and 891 (22.4%) female; adenocarcinoma was predominant in both groups, while squamous cell cancer was observed more commonly in female patients (39.8% versus 15.1%, P < 0.001). Multivariable analysis demonstrated improved outcomes in female patients for overall survival (HRmales 1.24, 95% c.i. 1.07 to 1.44) and disease-free survival (HRmales 1.22, 95% c.i. 1.05 to 1.43), which was caused by the adenocarcinoma subgroup, whereas this difference was not confirmed in squamous cell cancer. Male patients presented higher health-related quality of life functional scores but also a higher risk of financial problems, while female patients had lower overall summary scores and more persistent gastrointestinal symptoms. Conclusion: This study reveals uniquely that female sex is associated with more favourable long-term survival after curative treatment for oesophageal cancer, especially adenocarcinoma, although long-term overall and gastrointestinal health-related quality of life are poorer in women

Influence of cardiac decentralization on cardioprotection.

The role of cardiac nerves on development of myocardial tissue injury after acute coronary occlusion remains controversial. We investigated whether acute cardiac decentralization (surgical) modulates coronary flow reserve and myocardial protection in preconditioned dogs subject to ischemia-reperfusion. Experiments were conducted on four groups of anesthetised, open-chest dogs (n = 32): 1- controls (CTR, intact cardiac nerves), 2- ischemic preconditioning (PC; 4 cycles of 5-min IR), 3- cardiac decentralization (CD) and 4- CD+PC; all dogs underwent 60-min coronary occlusion and 180-min reperfusion. Coronary blood flow and reactive hyperemic responses were assessed using a blood volume flow probe. Infarct size (tetrazolium staining) was related to anatomic area at risk and coronary collateral blood flow (microspheres) in the anatomic area at risk. Post-ischemic reactive hyperemia and repayment-to-debt ratio responses were significantly reduced for all experimental groups; however, arterial perfusion pressure was not affected. Infarct size was reduced in CD dogs (18.6 ± 4.3; p = 0.001, data are mean ± 1 SD) compared to 25.2 ± 5.5% in CTR dogs and was less in PC dogs as expected (13.5 ± 3.2 vs. 25.2 ± 5.5%; p = 0.001); after acute CD, PC protection was conserved (11.6 ± 3.4 vs. 18.6 ± 4.3%; p = 0.02). In conclusion, our findings provide strong evidence that myocardial protection against ischemic injury can be preserved independent of extrinsic cardiac nerve inputs