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1.
J Stroke Cerebrovasc Dis ; 33(1): 107463, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38006768

RESUMEN

INTRODUCTION: The intricate relationship between Chagas disease and ischemic stroke remains unclear. Limited evidence exists concerning secondary prophylaxis, etiological diagnosis, and stroke-related determinants. This study aims to discern factors linked to stroke in Chagas disease by contrasting patients with and without a history of ischemic stroke. METHODS: Retrospective data from all outpatient Chagas disease patients from two Brazilian hospitals - one Chagas center and one stroke clinic - were examined. Descriptive analyses were conducted to identify stroke-associated factors. Variables were compared between patients with and without ischemic stroke history. RESULTS: Among 678 subjects, 72 had experienced stroke. Univariate associations with stroke included male gender, heart failure, prior or ongoing alcoholism, electrocardiographic features (non-sinus rhythm, left bundle branch, right bundle branch block, left anterosuperior fascicular block, atrial fibrillation), as well as echocardiographic findings indicative of reduced left ventricular ejection fraction and segmental abnormalities. After logistic regression (multivariate analysis), congestive heart failure, right bundle branch block, left anterosuperior divisional block, and atrial fibrillation retained independent associations. CONCLUSION: In this study, cardiac involvement emerged as the predominant factor correlated with stroke in Chagas disease. While atherosclerosis-related risk factors were prevalent, their influence on ischemic stroke in Chagas disease appeared limited.


Asunto(s)
Fibrilación Atrial , Cardiomiopatía Chagásica , Enfermedad de Chagas , Insuficiencia Cardíaca , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Masculino , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Fibrilación Atrial/complicaciones , Estudios de Casos y Controles , Estudios Retrospectivos , Volumen Sistólico , Bloqueo de Rama/complicaciones , Función Ventricular Izquierda , Enfermedad de Chagas/complicaciones , Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/epidemiología , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/epidemiología , Factores de Riesgo , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/etiología , Accidente Cerebrovascular Isquémico/complicaciones , Electrocardiografía/efectos adversos
2.
J Pediatr Hematol Oncol ; 45(7): e817-e822, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37526408

RESUMEN

The therapeutic approach to Wilms tumor (WT) is multidisciplinary and leads to significant patient impairment, increasing the risk of nutritional compromise and malnutrition. Children with cancer are vulnerable to sarcopenia which has been recognized as a negative impact of anticancer therapy. Recent studies have highlighted the reduction in the total psoas muscle area (TPMA) to be associated with a poor prognosis in many pediatric diseases, including cancer. This study aims to evaluate changes in the TPMA compartment during the treatment of children with WT. An observational, longitudinal, and retrospective study was undertaken in a single institution evaluating children (1 to 14 y, n=38) with WT between 2014 and 2020. TPMA was assessed by the analysis of previously collected, electronically stored computed tomography images of the abdomen obtained at 3 time points: diagnosis, preoperatively, and 1 year after surgery. For all patients, TPMA/age were calculated with a specific online calculator. Our data show a high incidence of sarcopenia (55.3%) at diagnosis which increased after 4 to 6 weeks of neoadjuvant chemotherapy (73.7%) and remained high (78.9%) 1 year after the surgical procedure. Using TPMA/age Z-score curves we have found significant and rapid muscle loss in children with WT, with little or no recovery in the study period.


Asunto(s)
Neoplasias Renales , Desnutrición , Sarcopenia , Tumor de Wilms , Niño , Humanos , Neoplasias Renales/complicaciones , Desnutrición/complicaciones , Pronóstico , Estudios Retrospectivos , Sarcopenia/diagnóstico , Sarcopenia/etiología , Tumor de Wilms/complicaciones , Tumor de Wilms/terapia , Estudios Longitudinales
3.
J Clin Immunol ; 34(8): 991-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25205548

RESUMEN

PURPOSE: Regulatory T cells are involved in the clinical course of chronic Chagas disease, possibly because they exercise a control in the patient's inflammatory response to Trypanosoma cruzi. This study analyzed the levels of CD4 + CD25+ T cells in chronic Chagas disease patients after in vitro stimulation of the peripheral blood mononuclear cells with CRA (Cytoplasmic Repetitive Antigen) or FRA (Flagellar Repetitive Antigen) T. cruzi antigens. METHODS: Groups of patients with the cardiac form and indeterminate form; and non-infected individuals, were selected. The CD4 + CD25+ T lymphocyte population, as well as the FoxP3 expression and the IL10 production, were evaluated by flow cytometry after stimulation with CRA or FRA. RESULT: The IND group presented higher levels of CD4 + CD25+ T cells than the CARD group. However, there was no evidence of a relationship between FoxP3 and IL10 with any of the chronic forms. CONCLUSIONS: Our results suggest the possible involvement of CD4 + CD25+ T cells specific to CRA and FRA in controlling the progression of clinical outcomes. Though, further studies are needed to define which mechanisms activate regulatory T cells and lead to pathology control in chronic human Chagas disease.


Asunto(s)
Antígenos de Protozoos/inmunología , Linfocitos T CD4-Positivos/inmunología , Enfermedad de Chagas/inmunología , Regulación de la Expresión Génica/inmunología , Proteínas Recombinantes de Fusión/inmunología , Trypanosoma cruzi/inmunología , Células Cultivadas , Citometría de Flujo , Humanos , Subunidad alfa del Receptor de Interleucina-2/genética
4.
Clin Obes ; : e12688, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38943556

RESUMEN

Obesity increases serum triglycerides and decreases high-density lipoprotein cholesterol (HDL-C). The objective is to explore some functions of HDL, cholesterol transfers and antioxidant, in subjects with grade I (G1-OB) and III (G3-OB) obesity and effects of bariatric surgery on G3-OB. Fifteen G3-OB patients (43 ± 6 years, BMI 49 ± 3 kg/m2) were studied before and 1 year after bariatric surgery; 15 G1-OB (32 ± 2 years, 32 ± 2 kg/m2) and 15 normal weight (NW) (38 ± 6 years, 22 ± 1 kg/m2) were also studied. HDL diameter, cholesterol transfer to HDL and antioxidant capacity of HDL were determined. G3-OB had higher triglycerides and lower HDL-C; G1-OB had higher triglycerides than NW but HDL-C was equal. Compared to NW, HDL size was smaller in G3-OB but equal in G1-OB. One year after bariatric surgery, BMI and triglycerides of G3-OB decreased (p < .0001 and p = .0012, respectively) and HDL-C increased (p < .0001), equalling of NW group. Antioxidant capacity and cholesterol transfers were not different in groups and were unchanged 1 year after bariatric surgery in G3-OB. HDL antioxidant capacity and transfer of cholesterol to HDL were not defective in obesity despite HDL-C reduction and smaller HDL size. In addition, pronounced weight loss by bariatric surgery did not change those protective functions.

5.
Circulation ; 125(20): 2454-61, 2012 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-22523306

RESUMEN

BACKGROUND: Previous studies suggested that transplantation of autologous bone marrow-derived mononuclear cells (BMNCs) improves heart function in chronic chagasic cardiomyopathy. We report the results of the first randomized trial of BMNC therapy in chronic chagasic cardiomyopathy. METHODS AND RESULTS: Patients 18 to 75 years of age with chronic chagasic cardiomyopathy, New York Heart Association class II to IV heart failure, left ventricular ejection fraction (LVEF) <35, and optimized therapy were randomized to intracoronary injection of autologous BMNCs or placebo. The primary end point was the difference in LVEF from baseline to 6 and 12 months after treatment between groups. Analysis was by intention to treat and powered to detect an absolute between-group difference of 5. Between July 2005 and October 2009, 234 patients were enrolled. Two patients abandoned the study and 49 were excluded because of protocol violation. The remaining 183 patients, 93 in the placebo group and 90 in the BMNC group, had a trimmed mean age of 52.4 years (range, 50.8-54.0 years) and LVEF of 26.1 (range, 25.1-27.1) at baseline. Median number of injected BMNCs was 2.20×10(8) (range, 1.40-3.50×10(8)). Change in LVEF did not differ significantly between treatment groups: trimmed mean change in LVEF at 6 months, 3.0 (1.3-4.8) for BMNCs and 2.5 (0.6-4.5) for placebo (P=0.519); change in LVEF at 12 months, 3.5 (1.5-5.5) for BMNCs and 3.7 (1.5-6.0) for placebo (P=0.850). Left ventricular systolic and diastolic volumes, New York Heart Association functional class, Minnesota quality-of-life questionnaire, brain natriuretic peptide concentrations, and 6-minute walking test did also not differ between groups. CONCLUSION: Intracoronary injection of autologous BMNCs does not improve left ventricular function or quality of life in patients with chronic chagasic cardiomyopathy.


Asunto(s)
Trasplante de Médula Ósea/métodos , Cardiomiopatía Chagásica/terapia , Calidad de Vida , Función Ventricular Izquierda , Adolescente , Adulto , Anciano , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intralesiones , Masculino , Persona de Mediana Edad , Actividad Motora , Trasplante Autólogo , Insuficiencia del Tratamiento , Adulto Joven
6.
Neural Netw ; 143: 698-708, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34418872

RESUMEN

This paper proposes a new model of a real weights quantum neuron exploiting the so-called quantum parallelism which allows for an exponential speedup of computations. The quantum neurons were trained in a classical-quantum approach, considering the delta rule to update the values of the weights in an image database of three distinct patterns. We performed classical simulations and also executed experiments in an actual small-scale quantum processor. The results of the experiments show that the proposed quantum real neuron model has a good generalisation capacity, demonstrating better accuracy than the traditional binary quantum perceptron model.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Bases de Datos Factuales , Neuronas
7.
Antibiotics (Basel) ; 10(11)2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34827219

RESUMEN

Lipid transfer proteins (LTPs) are among the most promising plant-exclusive antimicrobial peptides (AMPs). They figure among the most challenging AMPs from the point of view of their structural diversity, functions and biotechnological applications. This review presents a current picture of the LTP research, addressing not only their structural, evolutionary and further predicted functional aspects. Traditionally, LTPs have been identified by their direct isolation by biochemical techniques, whereas omics data and bioinformatics deserve special attention for their potential to bring new insights. In this context, new possible functions have been identified revealing that LTPs are actually multipurpose, with many additional predicted roles. Despite some challenges due to the toxicity and allergenicity of LTPs, a systematic review and search in patent databases, indicate promising perspectives for the biotechnological use of LTPs in human health and also plant defense.

8.
IEEE Trans Neural Netw Learn Syst ; 31(9): 3741-3746, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31562110

RESUMEN

The ability of artificial neural networks (ANNs) to adapt to input data and perform generalizations is intimately connected to the use of nonlinear activation and propagation functions. Quantum versions of ANN have been proposed to take advantage of the possible supremacy of quantum over classical computing. To date, all proposals faced the difficulty of implementing nonlinear activation functions since quantum operators are linear. This brief presents an architecture to simulate the computation of an arbitrary nonlinear function as a quantum circuit. This computation is performed on the phase of an adequately designed quantum state, and quantum phase estimation recovers the result, given a fixed precision, in a circuit with linear complexity in function of ANN input size.

9.
Lipids ; 52(8): 703-709, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28660528

RESUMEN

Plasma lipids have been extensively studied in sedentary and in subjects practicing exercise training, but not in extreme inactivity as occurs in bedridden patients. This is important for the care of bedridden patients and understanding the overall plasma lipid regulation. Here, we investigated plasma lipids, lipid transfers to HDL and inflammatory markers in bedridden patients. Fasting blood samples were collected from 23 clinically stable bedridden patients under long-term care (>90 days) and 26 normolipidemic sedentary subjects, paired for age and gender. In vitro transfer of four lipids to HDL was performed by incubating plasma with donor nanoparticles containing radioactive lipids. Total (193 ± 36 vs 160 ± 43, p = 0.005), LDL (124 ± 3 vs 96 ± 33 p = 0.003) and HDL-cholesterol (45 ± 10 vs 36 ± 13, p = 0.008), apolipoprotein A-I (134 ± 20 vs 111 ± 24, p = 0.001) and oxidized LDL (53 ± 13 vs 43 ± 12, p = 0.011) were lower in bedridden patients, whereas triglycerides, apolipoprotein B, CETP and LCAT were equal in both groups. Transfers of all lipids, namely unesterified cholesterol, cholesterol esters, triglycerides and phospholipids, to HDL were lower in bedridden patients, probably due to their lower HDL-cholesterol levels. Concentrations of IL-1ß, IL-6, IL-8, HGF and NGF were higher in bedridden patients compared to sedentary subjects. In conclusion, inactivity had great impact on HDL, by lowering HDL-cholesterol, apolipoprotein A-I and thereby cholesterol transfers to the lipoprotein, which suggests that inactivity may deteriorate HDL protection beyond the ordinary sedentary condition.


Asunto(s)
Apolipoproteína A-I/análisis , Biomarcadores/sangre , HDL-Colesterol/sangre , Inflamación/metabolismo , Lipoproteínas LDL/análisis , Adulto , Apolipoproteína A-I/sangre , Personas Encamadas , Ésteres del Colesterol , Femenino , Factor de Crecimiento de Hepatocito/sangre , Humanos , Interleucina-6/sangre , Interleucina-8/sangre , Lípidos/sangre , Lipoproteínas LDL/sangre , Masculino , Persona de Mediana Edad , Factor de Crecimiento Nervioso/sangre , Conducta Sedentaria
10.
Rev Col Bras Cir ; 44(5): 505-510, 2017.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-29019581

RESUMEN

OBJECTIVE: to investigate spontaneous resolution rate of a series of patients with physiologic phimosis in relation to observation time and presence of symptoms. METHODS: retrospective and longitudinal follow-up study of patients with physiologic phimosis, that did not apply topic treatment. These patients were invited for a new visit for reevaluation, or recent data were obtained by chart analysis. Spontaneous resolution rate was determined and statistically compared to age, presence of symptoms at first medical visit and time until reevaluation. RESULTS: seventy one patients were included. Medium time of observation from first visit to reevaluation was 37.4 months. There was spontaneous resolution of phimosis in 32 (45%) patients. Children with spontaneous resolution were younger at initial diagnosis and were observed during a longer period of time. Most asymptomatic patients at first visit presented spontaneous resolution. However, it was not possible to stablish a significant relationship between presence of symptoms and evolution of physiologic phimosis. CONCLUSIONS: time of observation was the main determinant of spontaneous resolution of patients with physiologic phimosis, reinforcing the current more conservative approach regarding circumcision of those patients.


Asunto(s)
Fimosis , Adolescente , Niño , Preescolar , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Fimosis/terapia , Remisión Espontánea , Estudios Retrospectivos , Factores de Tiempo , Espera Vigilante
11.
Neural Netw ; 76: 55-64, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26878722

RESUMEN

In this work, we propose a quantum neural network named quantum perceptron over a field (QPF). Quantum computers are not yet a reality and the models and algorithms proposed in this work cannot be simulated in actual (or classical) computers. QPF is a direct generalization of a classical perceptron and solves some drawbacks found in previous models of quantum perceptrons. We also present a learning algorithm named Superposition based Architecture Learning algorithm (SAL) that optimizes the neural network weights and architectures. SAL searches for the best architecture in a finite set of neural network architectures with linear time over the number of patterns in the training set. SAL is the first learning algorithm to determine neural network architectures in polynomial time. This speedup is obtained by the use of quantum parallelism and a non-linear quantum operator.


Asunto(s)
Computadores , Redes Neurales de la Computación , Algoritmos
12.
IEEE Trans Neural Netw ; 16(4): 996-9, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16121742

RESUMEN

In this letter, the computational power of a class of random access memory (RAM)-based neural networks, called general single-layer sequential weightless neural networks (GSSWNNs), is analyzed. The theoretical results presented, besides helping the understanding of the temporal behavior of these networks, could also provide useful insights for the developing of new learning algorithms.


Asunto(s)
Algoritmos , Modelos Estadísticos , Redes Neurales de la Computación , Reconocimiento de Normas Patrones Automatizadas/métodos , Simulación por Computador
13.
Respir Physiol Neurobiol ; 180(2-3): 269-74, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22193337

RESUMEN

Were evaluated individuals divided into two groups: we studied chronic heart failure (CHF) (19 patients with CHF plus cardiomegaly) and control (12 healthy volunteers) during performance of inspiratory loaded breathing (ILB). We evaluated: spirometry, functional capacity through the six-minute walk test (6MWT), and distribution of thoracoabdominal volumes via optoelectronic plethysmography (OEP), namely volume variations of pulmonary rib cage (Vrc,p), abdominal rib cage (Vrc,a), and abdomen (Vab). In each compartment, the percentage contributions of right and left sides were also calculated. During ILB, patients with heart failure were characterized by a significant reduction of the Vrc,a volume variations compared to the control group. Correlations were found between left %Vrc,a on the left side measured during ILB and left ventricular ejection fraction (r=0.468; p=0.049), and dyspnea after the 6MWT (r=-0.878; p<0.01).Then, patients with CHF and cardiomegaly are characterized by a reduced mobility in left part of the lower part of the rib cage, that contributes leading to increased perception of dyspnea during submaximal exercise.


Asunto(s)
Insuficiencia Cardíaca/patología , Mecánica Respiratoria/fisiología , Pared Torácica/patología , Adulto , Anciano , Cardiomegalia/patología , Estudios de Cohortes , Estudios Transversales , Disnea/fisiopatología , Femenino , Capacidad Residual Funcional/fisiología , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Pletismografía , Pruebas de Función Respiratoria , Músculos Respiratorios/fisiología , Capacidad Vital/fisiología , Adulto Joven
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