scholarly journals Diastolic Dysfunction Accompanies Alterations in Myocardial Structure, Cellular Composition and Macrophage Polarization in Survivors of Ionizing Radiation Exposure

2020 ◽  
Author(s):  
Kristofer T. Michalson ◽  
Gregory O. Dugan ◽  
David L. Caudell ◽  
J. Mark Cline ◽  
Dalane W. Kitzman ◽  
...  
Keyword(s):  
Heart Disease ◽  
Single Dose ◽  
Ionizing Radiation ◽  
Diastolic Dysfunction ◽  
Radiation Exposure ◽  
Left Ventricular ◽  
M1 Macrophages ◽  
Radiation Induced ◽  
Lv Diastolic Dysfunction ◽  
Ionizing Radiation Exposure

ABSTRACTRationaleRadiation induced heart disease (RIHD) is a significant delayed/late effect of ionizing radiation exposure.ObjectiveTo determine the cardiac effects of total body irradiation (TBI) in male rhesus macaques, a translational non-human primate (NHP) model.Methods and ResultsEchocardiography was performed on survivors of a single dose (6.4-8.5 Gy) of TBI (n=34) and non-irradiated controls (n=26) divided into longer (LT IRR) and shorter term (ST IRR) survivors and controls to assess the effects of time since TBI on phenotypes. LT IRR had increased Doppler transmitral early filling velocities (E), decreased early mitral annular descent velocities (e’), and higher E/e’ ratio compared to LT CTL (all p≤0.05), indicating left ventricular (LV) diastolic dysfunction. Echocardiographic stroke volume, cardiac output, and end-diastolic and systolic volumes were also lower in LT IRR than controls (all p ≤ 0.05). ST IRR had similar alterations in LV diastolic function but not in cardiac volumetric measures. Analyses of LV, interventricular septum (IVS), and right ventricle (RV) myocardium from deceased irradiated animals (n=17) exposed to a single dose (6.9-8.05 Gy) TBI and non-irradiated controls (n=12) showed that IRR animals had decreased LV and IVS capillary density, and increased LV fibrosis, pan-cardiac fibroblast and macrophage staining, LV and IVS M2 macrophages, and pan-cardiac M1 macrophages (all p<0.05). While M2 predominated over M1 macrophages in both groups, M1 showed greater increases than M2 in IRR.ConclusionsLV diastolic dysfunction due to radiation exposure may be due to a combination of capillary rarefication, activation and expansion of fibroblasts, and increased accumulation of both pro-fibrotic and pro-inflammatory macrophages, all of which lead to increased myocardial stiffness due to fibrosis. Collectively, these findings provide insights into the delayed effects of acute ionizing radiation exposure and suggest that therapies targeting macrophage regulation of fibrosis may mitigate radiation induced heart disease.

scholarly journals Sleep Apnea and Diabetes Predict Progression of Cardiac Diastolic Dysfunction in Pre-heart Failure Patients: a Prospective Cohort HSCAA Study

2020 ◽  
Author(s):  
Yonekazu Kidawara ◽  
Manabu Kadoya ◽  
Akiko Morimoto ◽  
Takashi Daimon ◽  
Miki Kakutani-Hatayama ◽  
...  
Keyword(s):  
Heart Failure ◽  
Heart Disease ◽  
Sleep Apnea ◽  
Diastolic Dysfunction ◽  
Prospective Cohort ◽  
Regression Line ◽  
Left Ventricular ◽  
Apnea Hypopnea Index ◽  
Annual Change ◽  
Lv Diastolic Dysfunction

Abstract [Background] Sleep apnea, a common co-morbid condition of diabetes, has been shown to be associated with established heart failure. However, its role in association of the presence of diabetes in the progression of cardiac diastolic function in pre-heart failure phase is not known. This prospective study is to longitudinally examine the predictive value of sleep apnea and diabetes on progression of left ventricular (LV) diastolic dysfunction in patients without heart disease.[Methods] Among 976 patients registered in HSCAA prospective cohort study, 517 without heart disease (175 type 2 diabetes, 342 non-diabetes) were followed with repeated echocardiography in every 1-3 years for a mean 34.7 months. LV diastolic dysfunction was determined by transmitral early inflow velocity/early diastolic tissue velocity (E/e´) >14. Annual change in E/e’ was calculated by using the slope of the linear regression line calculated from at least 3 echocardiographic measurements. Sleep apnea was determined by an apnomonitor device in conjunction with percutaneous oxygen saturation, and apnea hypopnea index (AHI) was calculated.[Results] Kaplan-Meier analyses revealed that subjects with diabetes or sleep apnea had a significantly (p<0.01) greater risk for LV diastolic dysfunction, with hazards ratio of 2.21 (1.41-3.47) and 2.23 (1.40-3.55), respectively. Subjects with sleep apnea exhibited significantly higher risk for LV diastolic dysfunction in non-diabetic subjects (p<0.01), while showed tendency of higher risk in diabetic subjects (p=0.10). The annual change of E/e’ was significantly and independently associated with both diabetes (β=0.278, p<0.01) and AHI (β=0.138, p<0.01). Finally, ROC analyses revealed that addition of AHI and diabetes to classical risk factors best predicted individuals with fast progression of diastolic dysfunction (annual change of E/e’ >1.0) with an AUC of 0.81.[Conclusions] In patients without heart disease, sleep apnea is an important predictor for progression of LV diastolic dysfunction. Its association is partly confounded, but still independent of the presence of diabetes.

scholarly journals Echocardiographic Assessment of Cardiac Dysfunction in Patients of Chronic Kidney Disease on Maintenance Hemodialysis

2019 ◽  
Vol 17 (2) ◽  
pp. 35-38
Author(s):  
Shyam Kumar BK ◽  
S.D. Bassi ◽  
Alok Kumar Sah ◽  
Devendra Acharya
Keyword(s):  
Chronic Kidney Disease ◽  
Heart Disease ◽  
Kidney Disease ◽  
Pericardial Effusion ◽  
Diastolic Dysfunction ◽  
Systolic Dysfunction ◽  
Left Ventricular ◽  
Maintenance Hemodialysis ◽  
P Value ◽  
Lv Diastolic Dysfunction

Objectives: The Aim of this study to assess and analyze the echocardiographic changes in chronic kidney disease patients on maintenance hemodialysis. Material and methods: We Performed Prospective study of echocardiographic changes in chronic kidney disease (CKD) patients undergoing maintenance hemodialysis at our institute. We performed M-mode echocardiography in 80 CKD patients without obvious clinical evidence of coronary artery disease, Valvular heart disease, congenital heart disease. Data was collected from November 2018 to Nov 2019. Results: 80 Patients Undergoing Hemodialysis were included in our study, out of them Echocardiography finding shown LV dilation and diastolic dysfunction in 39 (48.75%), left ventricular hypertrophy (LVH) in 41 (51.25%), systolic dysfunction and pericardial effusion in 22 (27.5%) and 11 (13.75%) patients respectively. RWMA was present in 10% and Valvular calcification was seen in 5 patients. In sub-group of patients with Hb<10 gm%, LVH was present in 32 (78.05%) vs 9 (21.95%) in patient group with Hb ≥ 10 gm% (p <0.01). Other Sub Group of Patients with BP > 140/90mmhg, LVH Was Present in 34 (82.92%) vs 7 (17.08%) in patients group with BP< 140/90 mm hg (p=0.02). In both sub group p value for systolic dysfunction, RWMA & pericardial effusion is statistically not significant. Conclusion: LV diastolic dysfunction and hypertrophy were most common echocardiographic findings. There was statistically significant correlation between anemia and presence of LVH and positive correlation between presence of hypertension and LVH.  

Low-Dose Ionizing Radiation from Medical Imaging

2016 ◽  
Author(s):  
Christoph I. Lee
Keyword(s):  
Medical Imaging ◽  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Low Dose ◽  
Additional Information ◽  
Radiation Induced Cancer ◽  
Radiation Induced ◽  
Effective Doses ◽  
Study Methodology ◽  
Ionizing Radiation Exposure

This chapter, found in the radiation exposure from medical imaging section of the book, provides a succinct synopsis of a key study examining low-dose ionizing radiation exposure and radiation-induced cancer risks. This summary outlines the study methodology and design, major results, limitations and criticisms, related studies and additional information, and clinical implications. The study reported that a substantial proportion of the nonelderly US population is exposed to medium to very high annual effective doses from medical imaging procedures. Strategies ensuring the appropriate use of medical imaging associated with ionizing radiation should be developed and adopted widely. In addition to outlining the most salient features of the study, a clinical vignette is included in order to provide relevant clinical context.

Impact of radiation induced crystallization on programmable metallization cell electrical characteristics and reliability

2019 ◽  
Vol 213 ◽  
pp. 53-66
Author(s):  
Yago Gonzalez-Velo ◽  
Arshey Patadia ◽  
Hugh J. Barnaby ◽  
Michael N. Kozicki
Keyword(s):  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Absorbed Dose ◽  
Electrical Characteristics ◽  
Programmable Metallization Cell ◽  
Radiation Induced ◽  
Programmable Metallization Cells ◽  
Ionizing Radiation Exposure ◽  
Metallization Cells ◽  
Induced Crystallization

Chalcogenide-based, programmable metallization cells (PMC) cells have been characterized after exposure to increasing levels of absorbed dose (i.e., ionizing radiation exposure).

The problem of ionizing radiation exposure of the radiologists in the opinion of students of Medical Faculties of the Medical University of Lublin

2008 ◽  
Vol 63 (1) ◽  
pp. 230-233
Author(s):  
Elżbieta Czekajska-Chehab ◽  
Piotr Przybylski ◽  
Marcin Pankowicz ◽  
Maria Korzec ◽  
Andrzej Drop
Keyword(s):  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Medical Faculties ◽  
Medical University ◽  
Ionizing Radiation Exposure

scholarly journals Effects of resveratrol against scattered radiation-induced testicular damage in rats

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Tarik Emre Sener ◽  
Beste Melek Atasoy ◽  
Ozge Cevik ◽  
Ozlem Tugce Cilingir Kaya ◽  
Sule Cetinel ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Radiation Exposure ◽  
Scattered Radiation ◽  
Caspase 3 ◽  
Sirtuin 1 ◽  
Protective Agent ◽  
Testicular Damage ◽  
Testosterone Levels ◽  
Protein Expressions ◽  
Ionizing Radiation Exposure

AbstractObjectivesTo investigate the possible protective effects of resveratrol against oxidative testicular damage due to scattered radiation during pelvic ionizing radiation exposure in rats.MethodsRats were divided into 5 groups; control, radiation, and radiation + resveratrol therapy in early and late periods. Under anesthesia, 20 Gy ionizing radiation was applied to prostatic region. Resveratrol was administered (10 mg/kg/day) orally before ionizing radiation exposure. Animals were decapitated at the end of 1st and 10th weeks. Biochemical markers of oxidative stress; caspase-3 and sirtuin-1 protein expressions; testosterone levels were evaluated, histological examinations were performed.ResultsSignificant increases in malondialdehyde, 8-hydroxy-deoxyguanosine levels, myeloperoxidase, and caspase-3 activities were observed after ionizing radiation exposure, also superoxide dismutase and glutathione activities were significantly decreased. Radiotherapy increased caspase-3 and decreased sirtuin-1 protein expressions. Resveratrol treatment significantly reversed these parameters and also reversed the decrease in testosterone levels back to control levels in late period.ConclusionResveratrol showed antioxidant and sirtuin-activating properties against oxidative damage caused by scattered radiation to testis and provided hormonal protection. These results suggest that resveratrol may be an alternative protective agent on testicular tissues against the effects of scattered pelvic radiation.

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