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111	Dysfonctions cardiaques transitoires induites par un exercice physique prolongé : Exploration mécanistique par une approche translationnelle / Transient cardiac dysfunction induced by a prolonged and strenuous exercise : A translational approach of the underlying mechanisms of cardiac fatigue Vitiello, Damien 07 December 2011 (has links) L’activité physique régulière est bénéfique pour la santé cardiovasculaire. Cependant, destravaux ont rapporté des dysfonctions cardiaques après des exercices physiques prolongés (EPP) tels que les marathons ou les triathlons longue distance type "Ironman". Ces dysfonctions sont souvent associées à des dommages myocardiques. Récemment, des études échocardiographiques ont suggéré que ces dysfonctions étaient associées à des baisses de contractilité et de relaxation myocardiques.Toutefois, l’atteinte myocardique après un EPP reste à ce jour controversée et les mécanismes sousjacents de ces dysfonctions demeurent inconnus. Dans ce contexte, le but de ce travail de doctorat a été de vérifier la diminution de contractilité et/ou de relaxation du myocarde après un EPP ii) d’évaluer l’implication de la voie ß-adrénergique et du stress oxydant dans l’altération de la fonction cardiaque.Pour cela, une première approche clinique, basée sur l’utilisation de l’échocardiographie cardiaque haute résolution (et plus particulièrement une technique de pointe, le "Speckle TrackingEchocardiography") nous a permis d’appréhender la fonction myocardique par l’intermédiaire de l’évaluation des déformations et de la torsion du ventricule gauche pendant le cycle cardiaque. Une deuxième approche fondamentale, chez l’animal, nous a permis d’évaluer la fonction cardiaque après un EPP chez le rat au niveau de l’organe entier et de l’organe isolé dans des conditions basale et de stress (ß-adrénergique). Des investigations complémentaires ont été réalisées sur le tissu myocardique pour évaluer le stress oxydant (GSH/GSSG, MDA) et des marqueurs de dommages cellulaires cardiaques (troponines I) après avoir bloqué la NAD(P)H oxydase (Nox), enzyme fortement impliquée dans la production d’espèces réactives dérivées de l’oxygène au niveau cardiaque. Les résultats de ces travaux montrent clairement, chez l’Homme et l’animal, des baisses de contractilité et de relaxation myocardiques associées à une augmentation des marqueurs de dommages cellulaires cardiaques après un EPP. Alors que la voie ß-adrénergique ne semble pas être impliquée dans ces dysfonctions, nos résultats indiquent que le stress oxydant joue un rôle majeur, puisque lorsque la Nox est bloquée, la fonction cardiaque est majoritairement restaurée après l’EPP. / Regular physical activity is beneficial for cardiovascular health. However, recentstudies have uncovered the presence of cardiac dysfunctions following prolonged physical exercise(PPE), such as marathon racing, or long-distance triathlons like the “Ironman”. These cardiacdysfunctions are often associated with damage at the myocardial level. Recently, someechocardiographic studies suggested that these dysfunctions were linked to a diminished myocardialcontractility and relaxation capacity. Nonetheless, the specific impact of PPE on myocardial propertiesremains controversial, and the mechanisms underlying these dysfunctions are thus far unknown.Therefore, within this context, the objectives of this PhD research were to i) verify the purporteddecrease in myocardial contractility and relaxation capacity following PPE, and ii) evaluate the rolesof the B-adrenergic pathway and oxidative stress in the alteration of cardiac function. In order toexplore this adequately, two different approaches were used. Firstly, a clinical approach wasemployed, based on the use of high resolution echocardiography (or more specifically, a leading edgetechnique known as Speckle Tracking Echocardiography), and allowed us to characterise myocardialfunction via the evaluation of left ventricular strain and torsion during a cardiac cycle. The secondfundamental approach, using an animal model, allowed us to evaluate cardiac function following PPEin rats; at a whole organ (in vivo) level and at an isolated organ (ex vivo) level, during both resting andstress (ß-adrenergic) conditions. Complementary investigations were conducted on myocardial tissueto evaluate oxidative stress (GSH/GSSG,MDA) and markers of myocardial damage (troponin I), afterhaving blocked NAD(P)H oxidase (Nox); an enzyme strongly involved in the production of oxidativestress at the cardiac level. Our findings clearly demonstrate, in both humans and animals, a decrease inmyocardial contractility and relaxation capacity, associated with an increase in markers of myocardialdamage, following PPE. Whilst the ß-adrenergic pathway does not appear to be involved in thesedysfunctions, our results indicate that oxidative stress plays a major role, since cardiac function isrestored following PPE when the Nox is blocked. Exercice physique prolongé Fatigue cardiaque NAD(P)H oxydase Speckle Tracking Echocardiography Stress oxydant Troponines I cardiaques Voie ß-adrénergique Prolonged strenuous exercise Cardiac fatig NAD(P)H oxidase Speckle Tracking Echocardiography Oxidative stress Cardiac troponins I ß-adrenergique pathway 612
112	Altered Skeletal Muscle Excitation-Contraction Coupling in the R6/2 Transgenic Mouse Model for Huntington's Disease Miranda, Daniel R. January 2021 (has links) No description available. Biomedical Research Biology Physiology action potential duration prolonged calcium Ca2+ force excitation-contraction coupling EC coupling chloride potassium Cl- K+ inwardly rectifying Kir ClC-1 skeletal muscle Huntington's disease huntingtin release flux voltage gated KV KV1.5 KV3.4 trains electrophysiology current-clamp
113	The influence of early life contexts on child self-regulation: A key to life course wellness Bates, Randi Ann 27 August 2019 (has links) No description available. Nursing Developmental Biology Developmental Psychology Endocrinology Families and Family Life Health Health Sciences Physiological Psychology Public Health self-regulation chronic stress prolonged stress hair cortisol adversity socioeconomic disadvantage ecobiodevelopmental framework mother-child dyad toddler mediation parent-child relationship nutrition environment caregiver father context
114	Preventing fatal effects of overworking : Product design solution Adawi, Rahim January 2018 (has links) “Overworking to death” is a phenomenon that has been noticeable in developing countries. The cause of death is mainly through ischemic strokes. While the victims’ occupations differed, they all shared a common characteristic, being positioned in a sedentary work, ranging from IT workers to doctors. This project’s aim was to develop a product that prevented or decreased the strokes that derived from sedentary overwork. This was mainly tackled by preventing one of the three causes of developing blood props, slowed blood flow. In order to gather rich data of the phenomenon, a qualitative study was conducted in China, during two months. By doing an extensive structured sampling, information rich data could be gathered during a short period of time. Data were derived from observations, questionnaires and an interview, which then was interpreted to customer needs and the final product specification. The final product became a trouser with an in built dynamic compression mechanic, that can compress the veins mostly during sitting activities, in order to prevent blood stasis. The compression mechanic works like the Chinese finger trap; compressing the calves while sitting and stretching the legs forward. It is made only out of polysaccharides fibres; cotton and corn. / "Guolaosi" eller död från överarbete är ett fenomen som i regel uppkommer bland utvecklingsländer. Dödsorsaken är huvudsakligen genom stroke. Offrens yrken varierar allt från professorer, IT-arbetare till läkare. De delar dock en sak gemensamt; att arbeta under långa perioder stillasittande. Projektets mål var att utveckla en produkt som minskar dödliga följderna av sedentära överarbete, genom att förebygga en av de tre orsakerna för att utveckla blodproppar; saktad blodström. Målgruppen var då kineser av de yrken som hade tidigare drabbats av fenomenet. För att samla informationsrika data om fenomenet genomfördes en kvalitativ studie i Kina under två månader. Genom att göra en omfattande strukturerad provtagning kunde informationsrika data samlas under en kort tidsperiod. Fältstudien bestod av observationer, frågeformulär och en intervju, som då tolkades till kundbehov och eventuellt produktspecifikationen. Den slutliga produkten kom att bli ett par byxor med en inbyggd dynamisk komprimeringsmekanism, som kan komprimera venerna under sittande aktiviteter, för att förhindra saktad blodström. Kompressionsmekanismen fungerar som den kinesiska fingerfällan. Den komprimerar blodkärlen medan personen sitter och sträcker benen framåt. Produkten är konstruerad på så sätt att den kan tillverkas endast av polysackariders tråd, från bomull och majs. Vilket är lämpligt för Kinas lokala resurser. stroke DVT overworking karoshi guolaosi prolonged inactivity sedentary death product design China Sweden Sida MFS field study trouser pants sampling observation questionnaire interview blood circulation stasis cardiovascular disease cotton corn agenda 2030 Chinese finger trap textile fibre yarn soil erosion muscle pump mechanism gradual compression stockings GECS PECS pressure distribution blood clot veins therapy stool chair PE PTS economy class syndrome methodology plastic sample concept sketch stroke DVT överarbete karoshi guolaosi förlängd inaktivitet stillasittande död produkt design Kina Sverige Sida MFS fältstudie byxa byxor provtagning observation frågeformulär intervju blodcirkulation stasis kardiovaskulär sjukdom bomull majs agenda 2030 kinesisk fingerfälla textil fiber garn jord erosion muskel pump mekanism gradvis komprimering strumpor stödstrumpa tryck kraft GECS PECS tryckfördelning blod blodproppar vener terapi pall stol PE PTS ekonomi klass syndrom metodik plast prov koncept skiss Design Design Pharmacology and Toxicology Farmakologi och toxikologi Occupational Therapy Arbetsterapi Cardiac and Cardiovascular Systems Kardiologi Environmental Sciences Miljövetenskap Medical Ergonomics Medicinsk ergonomi Textile, Rubber and Polymeric Materials Textil-, gummi- och polymermaterial Composite Science and Engineering Kompositmaterial och -teknik Medical Materials Medicinska material och protesteknik

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