Effective detection of abnormal gait patterns in Parkinson's disease patients using kinematics, nonlinear, and stability gait features.

BACKGROUND AND OBJECTIVES: Parkinson's disease (PD) is a neurodegenerative disease that produces movement disorders and it is the second most common neurodegenerative disease after Alzheimer's. Among other symptoms, PD affects gait patterns and produces bradykinesia, abnormal changes in posture, and shortened strides. In this study we present a comprehensive analysis of three different feature sets to model those abnormal gait patterns. The proposed approach is evaluated upon three groups of subjects: PD patients, young healthy controls (YHC), and elderly healthy controls (EHC). METHODS: Three feature sets are created: (1) kinematic measures including those that allow modeling time, distance and velocity of the strides, (2) nonlinear dynamics including different measures extracted from embedded attractors resulting from the time-series of the gait signals, and (3) different stability measures extracted in the time and frequency-domains. Support Vector Machine, Random Forest and XGBoost classifiers are trained to automatically discriminate between PD patients and healthy subjects. RESULTS: Among the considered feature sets, three individual measures emerge as the ones that yield accurate detection of PD and could potentially be used in clinical practice. Accuracies of up to 87.0% and 90.0% are found for the classification between PD vs. YHC and PD vs. EHC, respectively, considering individual measures. CONCLUSIONS: This study contributes to a better understanding of abnormal gait patterns observed in PD patients. Particularly the introduced approach shows good results that could be potentially used in clinical practice as a tool to support the diagnosis and follow-up of the patients.

Coronary endothelial dysfunction in patients with acute-onset idiopathic dilated cardiomyopathy.

OBJECTIVES: This study sought to determine whether coronary endothelial dysfunction exists in patients with acute-onset idiopathic dilated cardiomyopathy (DCM) and to explore its relation to recovery of left ventricular systolic function in this patient population. BACKGROUND: Coronary endothelial dysfunction exists in chronic DCM, but its importance in the development and progression of ventricular dysfunction is not known. To address this issue we studied coronary endothelial function in patients with idiopathic DCM <6 months in duration and explored the relation between coronary endothelial function and subsequent changes in left ventricular ejection fraction (LVEF). METHODS: Ten patients with acute-onset idiopathic DCM (duration of heart failure symptoms 2.0 +/- 0.4 months [mean +/- SEM]) and 11 control patients with normal left ventricular function underwent assessment of coronary endothelial function during intracoronary administration of the endothelium-dependent vasodilator acetylcholine and the endothelium-independent vasodilator adenosine. Coronary cross-sectional area (CSA) was determined by quantitative coronary angiography and coronary blood flow (CBF) by the product of coronary CSA and CBF velocity measured by an intracoronary Doppler catheter. Patients with DCM underwent assessment of left ventricular function before and several months after the study. RESULTS: Acetylcholine infusion produced no change in coronary CSA in control patients but significant epicardial constriction in patients with DCM (-36 +/- 11%, p < 0.01). These changes were associated with increases in CBF in control patients (+118 +/- 49%, p < 0.01) but no change in patients with DCM. Infusion of adenosine produced increases in coronary caliber and blood flow in both groups. Follow-up assessment of left ventricular function was obtained in nine patients with DCM 7.0 +/- 1.7 months after initial study, at which time LVEF had improved by > or =0.10 in four patients. Multiple linear regression revealed a positive correlation between both the coronary CSA (r2 = 0.57, p < 0.05) and CBF (r2 = 0.68, p < 0.01) response to acetylcholine and the subsequent improvement in LVEF. CONCLUSIONS: Coronary endothelial dysfunction exists at both the microvascular and the epicardial level in patients with acute-onset idiopathic DCM. The preservation of coronary endothelial function in this population is associated with subsequent improvement in left ventricular function.

Coronary stenting in patients undergoing percutaneous transluminal coronary angioplasty during acute myocardial infarction.

Although coronary stenting has been useful in the treatment of patients with suboptimal results, abrupt closure, and threatening occlusion after percutaneous transluminal coronary angioplasty (PTCA), its use in patients with acute myocardial infarction (AMI) is controversial because of the presence of intracoronary thrombus. In this study intracoronary stenting was used to treat suboptimal results and complications in 30 patients (35 lesions) undergoing PTCA during AMI. There were 28 men and 2 women, mean age 58 +/- 12 years. Thirteen patients (43%) had undergone rescue PTCA because of unsuccessful thrombolysis. Four patients had Killip's grade IV, 5 Killip's grade III, and 21 Killip's grade < or = 2 heart failure. Stents were placed in the 35 lesions because of suboptimal result (n = 19), early loss (n = 9), abrupt closure (n = 2), and coronary dissection with threatening occlusion (n = 5). All stents were deployed successfully. In-hospital complications included 1 in-hospital death (3.0%); no patient required emergency coronary artery bypass graft surgery. One patient (3.0%) developed abrupt closure and was successfully treated with PTCA and intracoronary thrombolysis. Vascular complications requiring blood transfusion developed in 3 of 30 patients (10%). At 11.8 months (range 4 to 24) follow-up, there were no deaths or myocardial infarction. One patient underwent coronary artery bypass grafting. The remaining patients were free of angina at follow-up. Thus, intracoronary stents can be used successfully to treat both suboptimal results and complications occurring in patients undergoing PTCA during AMI.

Quantitative PET measurements of regional myocardial blood flow: observations in humans with ischemic heart disease.

This review focuses on several related issues concerning positron emission tomography measurements of regional myocardial blood flow using 13-N-ammonia in humans. The effect of partial volume correction on estimates of K1, the model parameter describing myocardial blood flow, is considered. In addition a new method for computing K1 images of myocardial flow distribution is briefly described and compared to a standard method. Potential differences between K1 and equilibrium levels of 13-N-ammonia in the myocardium for estimation of myocardial blood flow are discussed also. The issue of heterogeneity of myocardial blood flow and flow reserve in normal volunteers is considered from the clinical point of view in terms of evaluation of patients with ischemic heart disease. Finally, the use of absolute measurement of adenosine-stimulated myocardial blood flow to assess physiological significance of coronary artery stenoses is addressed.

El trabajo psicosocial: reflejo de posiciones éticas y políticas / The psychosocial work: reflex of ethical and political positions

CONCLUSIONES: 1) El debate suscitado por la multiplicación de acciones de asistencia médica, psicológica y psiquiátrica o mal llamadas acciones de guerra o en situaciones crónicas de violencia, es pertinente y necesario para establecer el trasfondo político que hay en los proyectos de ayuda humanitaria, así como los paradigmas de dignidad, de libertad, de autonomía y de igualdad que los sustentan. En ello adquiere vigencia la ética y la filosofía moral en diálogo con las ciencias sociales y con las ciencias naturales. 2) Al encuentro con culturas diferentes y en situación de pobreza y marginamiento no puede llegarse con ideas preconcebidas e inamovibles sobre lo que es mejor para ellas, no con pretensiones de ser poseedores de la verdad sobre lo que para ellos significa su situación. 3) El trabajo psicosocial no es un trabajo terapéutico adicional a un trabajo social, es una posición de solidaridad y de respeto para con los que sufren que exige un conocimiento de los mecanismos y de las condiciones sociales, económicas, políticas y culturales en que éstos se encuentran y que perpetúan su sufrimiento. Es la articulación de los esfuerzos de muchas personas, pero fundamentalmente de los mismos sufrientes para recuperar condiciones de dignidad y libertad. 4) La crítica a los paradigmas psiquiátricos sobre el trauma se basa en el desprecio u olvido de que ha hecho gala la psiquiatría, de las condiciones cualitativas que influencian las respuestas emocionales...(TRUNCADO A 1500 K)