Analysis

Cardiomyopathies - The special entity of myocarditis and inflammatory cardiomyopathy

Published on: 1st July, 2019

OCLC Number/Unique Identifier: 8192807959

Cardiomyopathy is a heart muscle disease with structural and functional myocardial abnormalities in the absence of coronary artery disease, hypertension, valvular disease, and congenital heart disease. However, it has become clear that diverse etiologies and clinical manifestations (e.g. arrhythmogenic right-ventricular cardiomyopathy/dysplasia (ARVC/D), ARVD/C, left-ventricular non-compaction cardiomyopathy (LVNC)) are responsible for the clinical picture of dilated cardiomyopathy (DCM). The American Heart Association (AHA) classification grouped cardiomyopathies into genetic, mixed and acquired forms, while the European Society of Cardiology (ESC) classification proposed the subgrouping of each major type of cardiomyopathy into familial or genetic, and nonfamilial or nongenetic, forms [1-4]. Cardiomyopathies are clinically heterogeneous diseases, and there are differences in sex, age of onset, rate of progression, risk of development of overt heart failure and likelihood of sudden death within each cardiomyopathy subtype [5]. Because of the complex etiology and clinical presentation, the diagnostic spectrum in cardiomyopathies spans the entire range of non-invasive and invasive cardiological examination techniques including genetic analysis. The exact verification of certain cardiomyopathies necessitates additional investigations. So, histological, immunohistological and molecular biological/virological investigations of endomyocardial biopsies are the gold standard to confirm the diagnosis of an inflammatory cardiomyopathy (DCMi) [6-10]. This review focuses on myocarditis and inflammatory cardiomyopathies underlying an immune-mediated process or persistent viral infection.
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Role of novel cardiac biomarkers for the diagnosis, risk stratification, and prognostication among patients with heart failure

Published on: 22nd August, 2019

OCLC Number/Unique Identifier: 8212771729

Background: Current guidelines for diagnosis and management of heart failure (HF) rely on clinical findings and natriuretic peptide values, but evidence suggests that recently identified cardiac biomarkers may aid in early detection of HF and improve risk stratification. The aim of this study was to assess the diagnostic and prognostic utility of multiple biomarkers in patients with HF and left ventricular systolic dysfunction (LVSD). Methods: High-sensitivity cardiac troponin I (cTnI), N-terminal pro b-type natriuretic peptide (NT-proBNP), interleukin-6 (IL-6), endothelin-1 (ET-1), pro-matrix metalloproteinase-9 (pMMP-9), and tumor necrosis factor-alpha (TNF-α) were measured using single-molecule counting technology in 200 patients with varying stages of HF. Plasma detection with cross-sectional associations of biomarkers across all HF stages, and advanced-therapy and transplant-free survival were assessed using multivariate analysis and Cox regression analyses, respectively. Results: NTproBNP, pMMP-9, IL-6 were elevated in early, asymptomatic stages of HF, and increased with HF severity. Higher circulating levels of combined IL-6, NTproBNP, and cTnI predicted significantly worse survival at 1500-day follow-up. Cox regression analysis adjusted for ACC/AHA HF stages demonstrated that a higher concentration of IL-6 and cTnI conferred greater risks in terms of time to death, implantation of left ventricular assist device (LVAD), or heart transplantation. Conclusion: Biomarkers of inflammation, LV remodeling, and myocardial injury were elevated in HF and increased with HF severity. Patients had a significantly higher risk of serious cardiac events if multiple biomarkers were elevated. These findings support measuring NTproBNP, cTnI and IL-6 among patients with HF and LVSD for diagnostic and prognostic purposes.
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Arrhythmia of the heart - computer analysis

Published on: 20th September, 2019

The problem of synchronization of oscillations of various physical nature is discussed. From the standpoint of the theory of synchronism, a model of the heart is considered as a system of four connected between self-oscillating links: two atria and two ventricles. The synchronous and asynchronous operating modes are considered at sinusoidal and relaxation oscillations. A computer program has been compiled that simulates the fluctuations in the heart using four differential equations. Four examples of calculation according to the program are given for asynchronous and synchronous operation modes. The possibility of evaluating the ablation procedure from the perspective of a computer model is discussed.
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Plaque morphology in diabetic vs. non diabetic patients assessed by Multi-Slice Computed Tomography coronary angiography

Published on: 4th October, 2019

OCLC Number/Unique Identifier: 8333008298

Background and Objectives: Multi-slice computed tomography (MSCT) provides high accuracy for noninvasive assessment of coronary artery disease (CAD). The introduction of the latest computed tomography technology allows comprehensive evaluation of various aspects of CAD, including the coronary calcium score, coronary artery stenosis, bypass patency, and myocardial function. This study aimed to assess the effect of DM on coronary arteries evaluated by MSCT-CA Comparing Plaque Morphology in Diabetic patients with Non-Diabetic Whoever Controlled or not assessed by HbA1c. Methods: In this study we randomly assigned 150 adult patients were diagnosed with suspected coronary artery disease underwent MSCT-CA for evaluation their coronaries regarding luminal stenosis, Plaque analysis, Remodeling index, SSS, SIS and Ca score. Results: There was statistically significant difference between diabetics & non-diabetic groups in LM lesions with (P = 0.029). also, the results of multivariate logistic regression analysis after adjustment for age and sex, diabetics were shown a trend toward more mixed plaque with statistically significant {(OR): 3.422, 95% CI 1.66-7.023, P = 0.001}; whereas, after adjustment for age, sex, history of hypertension, smoking, and hypercholesterolemia, patients with diabetes also shown a trend toward more mixed plaque with statistically significant (OR: 3.456, 95% CI 1.668-7.160, P = 0.001). It means significant differences in coronary atherosclerotic plaque burden and composition between diabetic and non-diabetic patients, with a higher proportion of mixed plaques, a more vulnerable form of atherosclerotic plaque in diabetics (P < 0.001) otherwise No significant difference. Conclusion: MSCT angiography may be useful for the identification of CAD in diabetic and non-diabetic patients. There were statistically significant differences in coronary atherosclerotic plaque burden and composition, with a higher proportion of mixed plaques, between diabetic and nondiabetic patients. Furthermore, MSCT may give accurate information about plaque characteristics according to different coronary risk factors, thereby identifying high risk features warranting a more intensive anti-atherosclerotic treatment.   
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Evaluation of the predictive value of CHA2DS2-VASc Score for no-reflow phenomenon in patients with ST-segment elevation myocardial infarction who underwent Primary Percutaneous Coronary Intervention

Published on: 28th October, 2019

OCLC Number/Unique Identifier: 8303626780

Objective: The aim of this study was to estimate the predictive clinical value of CHA2DS2-VASc score for no-reflow phenomena in patients having ST-segment elevation myocardial infarction (STEMI) who applied to primary percutaneous coronary intervention (PCI). Subjects and Methods: Three-hundred STEMI patients underwent primary PCI. They were classified into: group (1) included 27 patients with no-reflow and group (2) included 273 patients without no-reflow (control). CHA2DS2-VASc risk score was computed for each patient. Results: This study found statistically significant difference (p < 0.05) in multivariate analysis of the association between CHA2DS2-VASc score and no-reflow phenomenon. The predictive power of individual components in CHA2DS2-VASc score for no-reflow was statistically significant difference (p < 0.05). So, significantly higher CHA2DS2-VASc score is connected with higher risk of no-reflow and in-hospital mortality rate. Conclusion: Significantly higher CHA2DS2-VASc score is associated with higher risk of no- reflow phenomenon and in-hospital mortality rates in patients with STEMI who underwent primary PCI.
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A Systematic review for sudden cardiac death in hypertrophic cardiomyopathy patients with Myocardial Fibrosis: A CMR LGE Study

Published on: 4th November, 2019

OCLC Number/Unique Identifier: 1185948222

Background: Hypertrophic cardiomyopathy (HCM) patients have a predisposition for malignant VT/VF and consequently, sudden cardiac death (SCD). In single center studies, late gadolinium enhancement (LGE) defined fibrosis has been linked to VT/VF. However, despite innumerable investigations, SCD has not been definitely attributable to LGE. Explanations for these are believed to be related to insufficient statistical power. Methods: We performed an electronic search of MEDLINE, PubMed: and CMR abstracts for original data published or presented between Jan 2001 to Mar 2011. Key search terms: HCM, LV fibrosis, SCD and LGE. Studies were screened for eligibility based on inclusion criteria: referral for CMR exam with LGE for HCM; and follow-up for incidence of VT/VF and SCD. Categorical variables were evaluated between patient groups via Chi-square test. Results: A total of 64 studies were initially identified. Of these, 4 (6.3%) were identified and included (n = 1063 patients). Three prospective and one retrospective study were included. LGE was detected in 59.6% of patients. As expected, the presence of myocardial fibrosis was associated with VT/VF (x2 = 6.5, p < 0.05; OR 9.0, (95% CI 1.2 to 68.7). Moreover, myocardial fibrosis strongly predicted SCD (x2 = 6.6, p < 0.05; OR 3.3 (95% CI 1.2 to 9.7). Conclusion: Despite single center CMR studies, LGE has consistently predicted VT/VF while prediction of SCD has remained paradoxically unlinked. Although the lack of studies meeting our criteria limited our ability to perform a comprehensive meta-analysis, we have been able to demonstrate for the first time that LGE-defined fibrosis is a predictor of SCD in patients with HCM0.
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Long-Term Impact of Coronary Artery Disease in Lung Transplantation

Published on: 26th November, 2019

OCLC Number/Unique Identifier: 8440605468

Background: Adoption of the Lung Allocation Score (LAS) has led to increased listing of older patients and those with idiopathic pulmonary fibrosis (IPF) for lung transplantation (LTX). Older patients and those with IPF have higher prevalence of coronary artery disease (CAD), a relative contraindication for LTX. The impact of the LAS on CAD prevalence and cardiovascular morbidity in LTX recipients is unknown. Methods: Retrospective review of single institution database from January 2000 to December 2010. Patients with and without CAD were compared by age, gender, LAS, single vs double LTX, and transplant indication. Survival was calculated by Kaplan-Meier method, and statistical significance determined by log-rank method. Survival analysis was performed on all patients and by 3:1 propensity matching. Differences in CAD, gender, and indication were determined by Chi-squared test. Differences in LAS and age were calculated with a two-tailed t - test. Results: In the pre-LAS era, 6.2% (9/145) recipients had CAD vs. 9.2% (17/184) in the post-LAS era (p = 0.411). Among all patients, recipients with CAD had a worse long term survival as estimated by Kaplan-Meier method (p = 0.001), although there was no statistically significant difference after propensity matching ((p = 0.14). Although more recipients in the post-LAS era had a diagnosis of IPF [15/145 vs. 71/184 patients, (p < 0.001)], there was no difference in the prevalence of CAD in the IPF cohort compared to others. There were no differences in cardiovascular deaths among recipients with CAD, with IPF, or in the post-LAS era. Patients with a pre-transplant diagnosis of CAD had an descreased risk of new onset postoperative atrial fibrillation (AF) (p = 0.007; HR:0.133; CI:0.030-0.583). Conclusion: Adoption of the LAS was not associated with a significant change in proportion of recipients with CAD who underwent LTX at our institution, despite an increase in recipients with IPF. Recipients with CAD had a higher risk of developing new postoperative AF and worse survival than patients without CAD. Differences in survival, however, could not be attributed directly to CAD based on propensity matched analysis
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Angiotensin II type 1 receptor and the activation of Myosin Light-Chain Kinase and Protein Kinase C-βII: Mini Review

Published on: 17th February, 2020

OCLC Number/Unique Identifier: 8534733539

The involvement of the angiotensin II type 1 receptor in the Frank-Starling Law of the Heart, where the various activations are very limited, allows simple analysis of the kinase systems involved and thence extrapolation of the mechanism to that of angiotensin control of activation of cardiac and skeletal muscle contraction. The involvement of phosphorylation of the myosin light chain in the control of contraction is accepted but not fully understood. The involvement of troponin-I phosphorylation is also indicated but of unknown mechanism. There is no known signal for activation of myosin light chain kinase or Protein Kinase C-βII other than Ca2+/calmodulin but the former is constitutively active and thus has to be under control of a regulated inhibitor, the latter kinase may also be the same. Ca2+/calmodulin is not activated in Frank-Starling, i.e. there are no diastolic or systolic [Ca2+] changes. I suggest here that the regulated inhibition is by myosin light chain phosphatase and/or β-arrestin. Angiotensin activation, not involving G proteins. is by translocation of the β-arrestin from the sarcoplasm to the plasma membrane thus reducing its kinase inhibition action in the sarcoplasm. This reduced inhibition has been wrongly attributed to a mythical downstream agonist property of β-arrestin.
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ECG interpretation and commentary

Published on: 18th February, 2020

OCLC Number/Unique Identifier: 8550965055

This is demonstration of selected ECGs for learning or for exams; guided by lessons from great teachers as Prof. Hein Wellens MD. Here we provide advanced examples with comment and analysis.
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Clinical relevance linked to echocardiography diagnosis in Bland, White and Garland syndrome

Published on: 6th March, 2020

OCLC Number/Unique Identifier: 8560715071

Introduction: Bland, White and Garland syndrome is a coronary anomaly with high mortality without treatment. Its clinical presentation is varied which makes epidemiological documentation difficult. Echocardiography is a useful non-invasive tool for diagnosis. Objective: To determine the echocardiographic variables that lead to the diagnosis of Bland, White and Garland syndrome and their clinical relevance. Material: Observational, prospective and cross-sectional study in 31 patients of the “William Soler” Pediatric Cardiocenter, from 2005 to 2018. To check the association of echocardiographic variables with the diagnosis of Bland, White and Garland syndrome, an effectiveness study was carried out that included the analysis of the incidence of echocardiographic variables that lead to the diagnosis of this entity. The clinical relevance was estimated according to the minimum importance limit. The statistical validation of the research results adopted a significance level of less than 5% (p < 0.05). Results: The variables that facilitate the echocardiographic diagnosis of Bland, White and Garland syndrome were the echocardiographic visualization of the anomalous connection and the reversed flow in the anomalous left coronary artery. These echocardiographic measures have clinical relevance according to the quantification of risk estimators (incidence) the echocardiographic visualization of the anomalous connection, RR 39.00 and the reversed flow in the anomalous coronary artery, RR 26.31. LIM´s calculation value amounted to 6.31 and coincided with the risk estimators (incidence). Conclusion: The echocardiographic visualization of the anomalous origin of the left coronary artery from the pulmonary arterial trunk and the detection of the local intracoronary reversed flow instituted as factors to be considered for the effective diagnosis of the disease. The documentation of the diagnostic aspects of the syndrome through echocardiography contains high statistical value and clinical relevance.
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Recurrence of atrial fibrillation after pulmonary vein isolation, should we change the energy and technique?

Published on: 3rd April, 2020

OCLC Number/Unique Identifier: 8576354289

Background: Pulmonary vein isolation (PVI) is the accepted standard nowadays for atrial fibrillation (AF) ablation. The most widespread ablation techniques are cryoballoon (CB) and point-by-point radiofrequency (RF) ablation. Comparative studies between both techniques have shown their equivalence for the first ablation procedure, but no trial has explored the potential incremental benefit of crossing over the ablation technique after AF recurrence. Objective: To explore the potential incremental benefit of a crossover ablation strategy for AF recurrences, comparatively with repeating the same ablation energy used for the first procedure. Methods: Retrospective analysis of patients undergoing a second AF ablation procedure after documented AF recurrence. Patients were excluded if all 4 PV were isolated at the beginning of the second procedure or extra-PVI ablation was used for the second procedure. Crossover group (n = 16) included patients in which two different techniques were used for the first and second procedure (CB-RF or RF-CB). Control group (n = 23) for those with same ablation procedure (RF-RF of CB-CB). Acute procedure end-point was PVI of all four pulmonary veins. Patients were followed-up at 3, 6, and 12 months with an electrocardiogram and a 24 h-holter. Arrhythmia-free survival at 1 year after the second ablation procedure was studied, comparing efficiency and safety of the two approaches (crossover vs. same energy). Success was defined as freedom from AF or atrial tachycardia lasting > 30 s off antiarrhythmic drugs (AADs) Results: A cohort of 39 paroxysmal and persistent AF patients was analyzed. PVI after the second procedure was 100% in all patients in both groups. There were no baseline relevant differences between the two groups. No deaths or hospitalizations occurred during follow up (data censored at 24h moths). At 1 year, arrhythmia free-survival was significantly higher in the crossover group compared to control group [93,3% vs. 47,8%; HR 0.19 (0.06-0.66);p = 0,009]. Conclusion: Crossing the ablation technique (point-by-point radiofrequency or cryoballoon PVI) after AF recurrence significantly improved arrhythmia free-survival at one year, despite no difference in acute success (PVI isolation). Randomized controlled trials with a higher amount of patients are needed to confirm the results and widespread this approach.
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Effects of highest dose of sacubitril/valsartan association compared to lower doses on mortality and ventricular arrhythmias

Published on: 24th April, 2020

OCLC Number/Unique Identifier: 8588720714

Background: Sudden cardiac death is a major healthcare issue in reduced ejection fraction heart failure (HFrEF) patients. Recently, the new association of sacubitril/valsartan showed a reduction of both ventricular arrhythmias (VA) and mortality even at low dose compared to enalapril in HF patients. The purpose of our study was to assess whether the highest dose of sacubitril/valsartan compared to lower doses may improve the rate of death and VA in a population of patients with HFrEF and with an implantable cardiac defibrillator (ICD). Methods: 104 HF patients with reduced EF under sacubitril/valsartan with an ICD were divided in 2 groups: the first one with the lower doses of sacubitril/valsartan (24/26 mg or 49 mg/51 mg twice daily) and the second with the maximal dose (97mg/103mg twice daily). The primary outcome was a composite of death or appropriate ICD therapy for VA. Results: After a median follow-up of 14 months, 39 patients were treated with lower doses and 65 patients with the highest dose. Patients from the lower doses group were older (70 [60-80] vs. 66 [60-70]; p = 0,03), more symptomatic at initiation (NYHA 3: 44% vs. 19%; p < 0,01) and more often in atrial fibrillation (31% vs. 12%; p = 0,04). The primary composite endpoint occurred in 14 patients (36%) in the low doses group versus 7 patients (11%) in high dose group (p < 0,01). This difference was particularly observed in the subgroup of patients with ischemic cardiomyopathy. In a multivariable analysis, the higher dose was independently associated with the primary outcome with an HR = 2,934 [IC 95% 1,147 – 7,504]; p = 0,03. Kaplan-Meier curve showed an early effect of the highest dose of sacubitril/valsartan association. Conclusion: Patients with HFrEF under the highest dose of sacubitril/valsartan showed better clinical outcomes with a decrease of both mortality or appropriated ICD therapies related to ventricular arrhythmias.
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Femoral venous closure: A single-centre retrospective analysis in real world all comers with MynxGrip® vascular closure device

Published on: 18th June, 2020

OCLC Number/Unique Identifier: 8628667812

Background: Vascular closure devices (VCD) are routinely used to achieve haemostasis following percutaneous arterial procedures. The extravascular polyethylene-glycol based MynxGrip® device (Cardinal Health) received FDA approval for use in the closure of femoral veins, but so far limited data is available on its use, especially with concomitant use of anticoagulants. Method: This is a retrospective analysis of data from a single-centre on the effectiveness and complication rates following the use of the MynxGrip® device for femoral venous closure in patients undergoing diagnostic/interventional (temporary pacing during balloon aortic valvuloplasty, or electrophysiology) procedures utilising 5-7F sheaths. Results: 85 patients (mean age 74 years) underwent femoral venous closure with the MynxGrip® device. 51.8% were male. The rate of concomitant anticoagulant or antiplatelet use was 52.9%. Device deployment was 100% successful with full haemostasis in all cases. There were no major vascular complications (bleeding, thrombosis, or infections). There was one case of a minor small venous hematoma which did not require treatment. The mean length of stay was less than 1 day (67.1% patients discharged the same day) and overnight stay only indicated by interventional procedure. Conclusion: These data support safety and efficacy of the MynxGrip® device for femoral venous closure with same-day discharge, even with concomitant aggressive antiplatelet and anticoagulant use. It has the potential for use in other large bore venous access sites. 
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Inter-Observer Variability of a Commercial Patient Positioning and Verification System in Proton Therapy

Published on: 6th February, 2017

OCLC Number/Unique Identifier: 7286354964

Purpose:Accurate patient positioning is crucial in radiation therapy. To fully benefit from the preciseness of proton therapy, image guided patient positioning and verification system is typically utilized in proton therapy. The purpose of this study is to evaluate the inter-observer variability of image alignment using a commercially available patient positioning and verification system in proton therapy. Methods:The VeriSuite patient positioning and verification system (MedCom GmbH, Darmstadt, Germany) provides a six degrees of freedom correction vector by registering two orthogonal x-ray images to digitally reconstructed radiograph (DRR) images that are rendered in real time from the planning computed tomography (CT) images. Six cases of various disease sites, including brain, head & neck, lung, prostate, pelvis, and bladder, were used in this study. For each case, the planning CT images and a daily orthogonal x-ray portal image pair were loaded into the VeriSuite system. The same set of x-ray images and CT images for each case were reviewed and aligned separately by each of the 10 radiation therapist, following the clinical procedure for the corresponding disease site. The resulting correction vectors were then recorded and analyzed. Results:Our study shows that the inter-observer variation (One standard deviation) in image alignment using the VeriSuite system ranged from 1.2 to 2.0 mm for translational correction and from 0.6 to 1.3 degrees for rotational correction for the six cases. The use of fiducial markers for prostate patient alignment achieved the least inter-observer variation while the bladder case produced the largest. Conclusions:Inter-observer variation in image alignment could be relatively large, depending on the complexity of patient anatomy, image alignment approach, and user experience and software limitations. Automatic registration and fiducial markers could potentially be used to align patient more accurately and consistently. To ensure adequate tumor coverage in proton therapy, inter-observer variability in patient alignment should be carefully evaluated and accounted for in patient setup uncertainty analysis and treatment planning margin determination.
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Mechanism-related Teratogenic, Hormone Modulant and other Toxicological effects of Veterinary and agricultural surfactants

Published on: 18th September, 2017

OCLC Number/Unique Identifier: 7325078577

Veterinary and agricultural surfactants are supposed to be inert additives, yet these substances commonly exert biological side-effects, in given cases synergistic with those of the active ingredients of these preparations. This is explicitly seen in altered toxicity of veterinary or pesticide formulations compared to their active ingredients alone. Neither the individual effects of these excipients, nor such combination effects are well-studied in toxicology, and therefore, possible toxicity consequences are occasionally not being considered at sufficient significance in the authorization, use and control of these substances. Risk assessment of these substances should cover all hazards they may represent, and corresponding levels of exposure. Surfactants used in veterinary and pesticide formulation enter the environment either by direct dispersion or by indirect release through excrement, leaching, sewage waters or sludge, and in turn, create potential exposure to a number of non-target organisms. Biochemical and (eco)toxicological hazards recently identified regarding certain agricultural surfactants include cytotoxicity (on cell lines of epithelial, neural and other tissues, as well as stem cells and tumor cells), endocrine disrupting effects, as well as aquatic ecotoxicity. This Mini Review summarizes toxicological effects identified in our studies in aquatic toxicity tests, in cell viability and cytotoxicity tests, in estrogenic activity assays, correlated with biochemical analysis of the surfactants and their decomposition. The conclusions are hoped to facilitate environmentally precautious revision of surfactants widely used in agriculture.
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Using Mathematical Procedure to Compute the Attenuation Coefficient in Spectrometry Field

Published on: 6th February, 2017

OCLC Number/Unique Identifier: 7286351538

In gamma-ray spectrometry, the analysis of the environmental radioactivity samples (soil, sediment and ash of a living organism) needs to know the linear attenuation coefficient of the sample matrix. This coefficient is required to calculate the self-absorption correction factor through the sample bulk. In addition, these parameters are very important because the unidentified samples can be different in the composition and density from the reference liquid sources which are usually used for efficiency calibration in the radioactive monitoring process. The present work is essentially concerned to introduce a mathematical method to calculate the linear attenuation coefficient without using any collimator. This method was based mainly on the calculations of the effective solid angle subtended by the source-to-the detector configurations, the efficiency transfer technique and the average path lengths through the samples itself. The method can be used as a tool for the calculation of the linear attenuation coefficient of unidentified materials with good facility to use it in the calibration process of γ-ray detectors, particularly in the study of soil samples. The results are compared with the data from NIST-XCOM to show how much the results are in close agreement and to give the validity of the approach.
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Empirical formulae for calculating γ-ray detectors effective solid angle ratio

Published on: 27th January, 2017

Determination of the detector efficiency using volumetric cylindrical sources is very important in various scientific and industrial fields, especially in the field of quantitative analysis. To calculate the absolute activity of any sample, the full-energy peak efficiency (FEPE) of the detector is needed. By applying the efficiency transfer method, the FEPE of the detector would be determined easily without using the standard sources. This approach depends on two main factors. The first one, is the reference efficiency of the reference source, which is determined experimentally, and the second one, is the calculation of the effective solid angle ratio between the sample and the reference source geometries. This work introduces an empirical formula for calculating the second factor for using two different sizes of NaI(Tl) detectors. The validity of this empirical formula was successfully demonstrated by comparing the calculating values with the experimental values.
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New Approach for Analysing the Discrepancy of Pretherapeutic Tc-99m and Intra-therapeutic I-131 uptake in Scintigraphies of Thyroid Autonomies using a Parametric 3D Analysis Program

Published on: 2nd January, 2017

OCLC Number/Unique Identifier: 7286427358

Introduction: Radioiodine therapy is a standard procedure in thyroid autonomy treatment. Discrepancies in the visual comparisons of the scintigraphies prepared for this purpose using Tc-99m-O4- and I-131 have been known for years. In this study a new method is used to calculate and perform a quantitative comparison of both uptakes using subtraction analysis and 3D imaging. The results and their causes are discussed together with practice-relevant conclusions for better clinical results. Material and Methods: The new method was used in 38 patients with thyroid autonomies for the subtraction analysis of standardized pretherapeutic and intratherapeutic scintigraphies. The parametric distribution of activity was calculated absolutely and as a percentage and displayed three-dimensionally. These results were compared with the visual assessment of the different scintigraphies by the experts. Inclusion criteria were pretherapeutic and intratherapeutic hyperthyroidism without medication affecting the thyroid. The time difference between acquiring the scintigraphies was 28 days maximum. Results: Activity distribution was visually discrepant in 39.5% of cases. 60.5% displayed comparable uptake. The calculated values showed reversed results after applying the new method. The results using our method show a higher rate of calculated discrepancies compared with visual analysis. Conclusion: Accurate functional imaging of the thyroid is next to further aspects very important in establishing the diagnosis and deciding about the therapy activity for thyroid treatment. In combination with clinical symptoms and laboratory values, Tc-99m-O4 - scintigram can be used for an orientated, preliminary assessment of functional disorders of the thyroid. But because of the higher rate of found discrepancies, the solely use of Tc-99m-O4 - scintigram is not always capable for exact and reliable diagnosis. The known reason for this is most probably due to the different biokinetics of both radiopharmaceuticals, which can be imaged more sensitively with this method. Consequently, a scintigram should be performed in the pretherapeutic radioiodine uptake test. Despite higher costs and radiation exposure, alternatively, pretherapeutic use of other diagnostic iodine isotopes like I-123 or -124 should be discussed, because they could overcome the limitation of the different biokinetics. Following this approach the preliminary assessment using Tc-99m-O4 - scintigraphy can be precised and double checked to improve diagnostic confi dence and treatment results for a better outcome of the patients.  
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An analysis of wild animals with respect to French Ethics and Law

Published on: 9th May, 2019

OCLC Number/Unique Identifier: 8163878958

Before discussing the crux of the matter, it is important to understand what “wild” signifies and the characteristics that define a wild animal. As contrasted to domesticated animals, a wild animal can be defined as an animal living freely in his natural habitat, independently of Man. These animals are only exposed to variations in the biological equilibrium, to the imperatives of their genetic program and live in a habitat that gives them the possibility of expressing it themselves. However, this definition is very narrow as there exist a number of species of wild animals that don’t live freely in their natural habitat. These animals are constrained by Man, who by creating a relationship of dependence, controls them and in turn becomes responsible for their sustenance. In such a situation, their habitat is no more their natural habitat but than which has been imposed on them by Man; such animals are said to be “held in captivity” or even “tamed”. In short, when talking about law and ethics related to wild animals, there are two things to be taken into account: wild animals that live in the wild and wild animals that live held in captivity by Man.
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Prevalence and seasonal variations of eggs of gastrointestinal nematode parasites of goats from smallholder farms in Mozambique

Published on: 23rd July, 2019

OCLC Number/Unique Identifier: 8206561393

A survey was carried out to determine the prevalence and seasonal variations of eggs of gastrointestinal nematodes in goats in four provinces of Mozambique, from November 2016 to October 2017 in Tete and Cabo Delgado, and from November 2016 to October 2018 in Maputo and Gaza. In each province, flocks were selected from both lowlands, located within the valleys of the rivers, and uplands which are located outside the valleys. Faecal samples were collected at monthly intervals to monitor faecal egg counts fluctuations. The modified McMaster technique was used for quantitative analysis of nematode eggs and for detecting cestode eggs in faecal samples. The sedimentation technique for detecting trematode eggs in faecal samples was used. A total of 2 703 samples were examined for nematode eggs and 2 587 for trematode eggs. Faecal examination indicated that between 18% and 100% of goats sampled were infected with gastro-intestinal nematodes. The prevalence varied according to the season of the year and the ecological conditions. The highest prevalence and worm egg counts were recorded at about the peak of the rainy season. Strongyloides papillosus, Calicophoron spp., Fasciola spp. and Schistosoma mattheei eggs were also found. Moniezia expansa and Moniezia benedeni eggs were found in all the four study areas but its prevalence was low and irregular. Based on the results of this study, which showed a clear seasonal pattern, strategic anthelmintic medications to effectively control helminth infections in goats in the different ecological zones of Mozambique are suggested.
Cite this ArticleCrossMarkPublonsHarvard Library HOLLISGrowKudosResearchGateBase SearchOAI PMHAcademic MicrosoftScilitSemantic ScholarUniversite de ParisUW LibrariesSJSU King LibrarySJSU King LibraryNUS LibraryMcGillDET KGL BIBLiOTEKJCU DiscoveryUniversidad De LimaWorldCatVU on WorldCat
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