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Vasculitis
Published in Jason Liebowitz, Philip Seo, David Hellmann, Michael Zeide, Clinical Innovation in Rheumatology, 2023
Michelle L. Robinette, Eli Miloslavsky, Zachary S. Wallace
Systemic vasculitis is a broad category of diseases that often have severe manifestations because of their predilection for vascular beds in the lungs, kidneys, and nerves, as well as the aorta and its main branches. Tissue damage occurs from ischemia, infarction, and/or hemorrhage and can be catastrophic. Vasculitides are most often classified according to their primary vessel involvement (small, medium, large, or variable), as defined in the Chapel Hill classification criteria (1) (Table 10.1).
Role of Vasoactive Intestinal Peptide in Myocardial Ischemia Reperfusion Injury
Published in Sami I. Said, Proinflammatory and Antiinflammatory Peptides, 2020
Dipak K. Das, Nilanjana Maulik, Richard M. Engelman
Ischemia, by definition, represents a phenomenon in which tissue is deprived of either partial or total blood flow in conjunction with hypoxia. Clinically this can occur during thrombolytic therapy and angioplasty, in which blood flow is temporarily interrupted (23). Prolonged myocardial ischemia can occur during open-heart surgery, when the heart must be arrested in order to permit surgical manipulations (24,25). Thus, ischemic insult may occur regionally or globally, either for a short period of time or for relatively longer periods, depending on the clinical setting. While short-term ischemia (usually less than 20 min) causes reversible tissue injury which may be completely restored, prolonged myocardial ischemia (more than 30 min) can lead to irreversible cellular injury, resulting from energy depletion, lactic acidosis, and inhibition of both glucose and fatty acid utilization (26,27).
Cross Talk Between Heat Shock and Oxidative Stress Inducible Genes During Myocardial Adaptation to Ischemia
Published in John J. Lemasters, Constance Oliver, Cell Biology of Trauma, 2020
Dipak K. Das, Nilanjana Maulik
Various methods are available to adapt the heart to ischemia. The one originally used consisted of subjecting the heart to repeated episodes of short durations of ischemia and reperfusion.17 This technique is very reproducible, and has been found to be valid for many animal models including dog, pig, rabbit, and rat.16–23 We will describe here the method used for the rat heart. Hearts can be excised from properly anesthetized rats, which are perfused for 10 min with nonrecirculating Krebs-Henseleit bicarbonate (KHB) buffer containing 3% bovine serum albumin. The KHB buffer consists of the following ion concentrations (in millimolars): 119.0 NaCl, 25.0 NaHCO3, 4.6 KCl, 1.2 KH2PO4, 1.2 MgSO4, 2.5 CaCl2, and 11.0 glucose. Coronary perfusion pressure and perfusate temperature are generally maintained at 100 cm H2O and 37°C, respectively. Hearts can be made globally ischemic by terminating the aortic flow for 5 min followed by 10 min of reperfusion (1 × PC). To induce repeated episodes of ischemia and reperfusion, this procedure may be repeated four times (4 × PC). Each preconditioning (1 × PC or 4 × PC) is followed by 60 min of reperfusion. Experiments are terminated at various points, viz., prior to preconditioning (baseline), after preconditioning, and after reperfusion. Heart biopsies are examined for the expression of oncogenes and stress-related genes, as well as antioxidative enzymes.
Predictive value of motor-evoked potentials for motor recovery in patients with hemiparesis secondary to acute ischemic stroke
Published in Annals of Medicine, 2023
Cheng-Chang Yen, Hsin-Hung Chen, Chao-Hsien Lee, Ching-Huang Lin
Ischemic stroke was diagnosed by a neurologist based on clinical manifestations and either brain computed tomography (CT) or magnetic resonance imaging (MRI). All patients with acute ischemic stroke received routine rehabilitation and treatment according to the treatment guidelines of the Taiwan Stroke Society for acute ischemic stroke. We collected the patients’ baseline information, including age, sex, smoking habit, drinking habit, body weight, height, comorbidities, and the National Institutes of Health Stroke Scale (NIHSS) score. NIHSS was assessed by a neurologist. Stroke location was determined using a brain CT scan and/or MRI and was categorized as cortical, subcortical, or brain stem. Motor function of the upper extremities was measured with the FMA (range: 0–66) at ≤10 days and 30 and 90 days after stroke onset by another neurologist. Proportional recovery was calculated as follows: Proportional recovery = (subsequent FMA score − initial FMA score)/(66 − initial FMA score). The subsequent FMA score was the score at 30 days and 90 days after the stroke. Post-stroke functional outcome was evaluated using the mRS at 90 days after stroke onset by the same neurologist. An mRS score of ≤1 was defined as a good functional outcome.
PM2.5 from diesel exhaust attenuated fisetin mediated cytoprotection in H9c2 cardiomyocytes subjected to ischemia reoxygenation by inducing mitotoxicity
Published in Drug and Chemical Toxicology, 2023
Bhavana Sivakumar, Gino A. Kurian
Ischemia reperfusion injury is an unavoidable injury during revascularization, mimicked invitro by using the ischemia re-oxygenation (IR) model. IR is a non-physiological, in-vitro experimental setting that simulates ischemia and reperfusion via altering both internal and external cellular environment. It also induces external stress via promoting hyperkalemia, acidosis, nutrient deprivation, and waste accumulation (Chen and Vunjak-Novakovic 2018). The physiological and pathological influence of IR is well documented in the literature, where it can possess both beneficial and detrimental effects depending on the duration and cell type (Kalogeris et al. 2012). In the heart, the detrimental effect of ischemia adds up in the presence of risk factors. Since ischemic injury is a bioenergetic problem, metabolic dyshomeostasis is considered to be the main pathological culprit. Mitochondria being the metabolic hub is expected to be dysfunctional with varying ischemic time points with the and co-existence of metabolic disorders like diabetes, obesity and so on.
Clinical significance and prognostic value of ST segment depression on ECG during exercise treadmill test in asymptomatic patients with moderate or severe aortic stenosis
Published in Scandinavian Cardiovascular Journal, 2022
Gard Mikael Saele Myrmel, Daanyaal Wasim, Ronak Rajani, Denise Parkin, John B. Chambers, Sahrai Saeed
First, the incidence of ST segment depression between 2 and 5 mm was not reported. If ST segment depression >2 mm is a cutpoint then our comparison might have been diluted by the inclusion of ST segment depression 2–5 mm in the control group. However, no other studies have shown ST segment depression >2 mm to be prognostically important so this is unlikely. Second, the burden of silent ischemia was not investigated. A recent study of patients with severe AS and normal exercise testing and LV ejection fraction showed that one out of five had a silent significant coronary artery disease despite the absence of inducible ischemia on ETT [32]. However, the true prevalence, clinical significance and prognostic value of silent ischemia in AS is still matter of further investigation. Third, the use of CT calcium score could add prognostic information in AS assessed as moderate by echocardiography. Finally, our study population was relatively young. Most of elderly patients with severe AS might not be able to perform ETT in a satisfactory manner.