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1.
Int J Numer Method Biomed Eng ; 40(7): e3826, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705952

RESUMO

This article introduces an observer-based control strategy tailored for regulating plasma glucose in type 1 diabetes mellitus patients, addressing challenges like unknown time-varying delays and meal disturbances. This control strategy is based on an extended Bergman minimal model, a nonlinear glucose-insulin model to encompass unknown inputs, such as unplanned meals, exercise disturbances, or delays. The primary contribution lies in the design of an observer-based state feedback control in the presence of unknown long delays, which seeks to support and enhance the performance of the traditional artificial pancreas by considering realistic scenarios. The observer and control gains for the observer-based control are computed through linear matrix inequalities formulated from Lyapunov conditions that guarantee closed-loop stability. This design deploys a soft and gentle dynamic response, similar to a natural pancreas, despite meal disturbances and input delays. Numerical tests demonstrate the scheme's effectiveness in glycemic level regulation and hypoglycemic episode avoidance.


Assuntos
Glicemia , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 1/sangue , Humanos , Glicemia/metabolismo , Insulina/metabolismo , Insulina/sangue , Pâncreas Artificial , Modelos Biológicos
2.
BMC Gastroenterol ; 20(1): 414, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33297984

RESUMO

BACKGROUND: In contrast to the well-characterized Celiac Disease (CD), the clinical scenarios encompassed by the non-celiac self-reported wheat sensitivity (NCSRWS) might be related to different antigens that trigger distinct immune-inflammatory reactions. Although an increased number of intestinal intraepithelial lymphocytes is observed at the inception of both diseases, the subsequent immunopathogenic pathways seem to be different. We aimed to describe the cytokine profile observed in the duodenal mucosa of patients with NCSRWS. METHODS: In a blind, cross-sectional study, we included duodenal biopsies from 15 consecutive untreated patients with active CD, 9 individuals with NCSRWS and 10 subjects with dyspepsia without CD and food intolerances. Immunohistochemistry and flow-cytometry were used to determine the presence of pro-inflammatory cytokine expressing monocytes and monocyte-derived dendritic cells involved in innate immune activation, cytokine-driven polarization and maintenance of Th1 and Th17/Th 22, and anti-inflammatory/profibrogenic cytokines. RESULTS: The percentage of cells expressing all tested cytokines in the lamina propria and the epithelium was higher in CD patients than in the control group. Cytokines that induce and maintain Th1 and Th17 polarization were higher in CD than in NCSRWS and controls, also were higher in NCSRWS compared to controls. Similar differences were detected in the expression of IL-4 and TGF-1, while IL-10-expressing cells were lower in NCSRWS patients than in controls and CD subjects. CONCLUSIONS: NCSRWS patients exhibit components of both, innate and adaptive immune mechanisms but to a lesser extent compared to CD.


Assuntos
Doença Celíaca , Duodeno , Estudos Transversais , Humanos , Mucosa Intestinal , Autorrelato
3.
Rev Neurol ; 56(6): 332-6, 2013 Mar 16.
Artigo em Espanhol | MEDLINE | ID: mdl-23483468

RESUMO

INTRODUCTION. Intracranial subependymomas are rare, slow-growing, noninvasive, benign tumors. They are most often located in the fourth ventricle. Most of these tumors are discovered incidentally during autopsy. Routine medical checkups using neuroimaging techniques have increased their diagnosis. Subependymomas may present with symptoms related to cerebrospinal fluid obstruction or mass effect. CASE REPORT. A 52-year-old man presented with severe headache and mental deterioration with memory disturbances and bradypsychia. Computed tomography and magnetic resonance imaging revealed a mass in the right lateral ventricle causing obstructive hydrocephalus. The tumour was totally removed through a right frontal transcortical approach. Histological examination showed a typical subependymoma. A complete neurological recovery was achieved after surgery. CONCLUSIONS. Subependymomas are rare low-grade glial neoplasm that commonly arise in the ventricular system. They have a low-proliferative potential but in these locations they can cause symptomatic hydrocephalus. Surgical removal of the mass and the restoration of the normal cerebrospinal fluid pathways constitute the optimal management strategy.


Assuntos
Neoplasias do Ventrículo Cerebral/diagnóstico , Glioma Subependimal/diagnóstico , Ventrículos Laterais/patologia , Biomarcadores Tumorais/análise , Neoplasias do Ventrículo Cerebral/complicações , Neoplasias do Ventrículo Cerebral/patologia , Neoplasias do Ventrículo Cerebral/cirurgia , Transtornos Cognitivos/etiologia , Confusão/etiologia , Craniotomia , Diagnóstico Diferencial , Glioma Subependimal/complicações , Glioma Subependimal/patologia , Glioma Subependimal/cirurgia , Cefaleia/etiologia , Humanos , Hidrocefalia/etiologia , Ventrículos Laterais/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Neuroepiteliomatosas/diagnóstico , Recuperação de Função Fisiológica
4.
Rev. neurol. (Ed. impr.) ; 56(6): 332-336, 16 mar., 2013. ilus
Artigo em Espanhol | IBECS | ID: ibc-110761

RESUMO

Introducción. Los subependimomas intracraneales son tumores benignos poco frecuentes, no invasivos y de lento crecimiento. Se localizan habitualmente en el cuarto ventrículo. La mayor parte de estos tumores se descubre incidentalmente como pequeñas lesiones durante la realización de estudios de autopsia. Los estudios con técnicas de neuroimagen han incrementado su diagnóstico. En los casos de pacientes sintomáticos con subependimomas, estos síntomas habitualmente se deben a la obstrucción del líquido cefalorraquídeo o por efecto masa. Caso clínico. Varón de 52 años que presentaba cefalea intensa y deterioro cognitivo con alteraciones de memoria y bradipsiquia. Las imágenes de tomografía computarizada y de resonancia magnética mostraron una lesión en el ventrículo lateral derecho que provocó hidrocefalia obstructiva. El tumor fue resecado totalmente a través de un abordaje frontal transcortical derecho. El examen histológico demostró hallazgos de subependimoma típico. Tras la cirugía, se consiguió una recuperación neurológica completa. Conclusiones. Los subependimomas son neoplasias gliales poco frecuentes que habitualmente crecen dentro del sistema ventricular. Tienen un bajo potencial proliferativo, pero en estas localizaciones pueden provocar hidrocefalia sintomática. La resección quirúrgica de la lesión y la restauración de las vías normales de circulación del líquido cefalorraquídeo constituyen la estrategia terapéutica óptima (AU)


Introduction. Intracranial subependymomas are rare, slow-growing, noninvasive, benign tumors. They are most often located in the fourth ventricle. Most of these tumors are discovered incidentally during autopsy. Routine medical checkups using neuroimaging techniques have increased their diagnosis. Subependymomas may present with symptoms related to cerebrospinal fluid obstruction or mass effect. Case report. A 52-year-old man presented with severe headache and mental deterioration with memory disturbances and bradypsychia. Computed tomography and magnetic resonance imaging revealed a mass in the right lateral ventricle causing obstructive hydrocephalus. The tumour was totally removed through a right frontal transcortical approach. Histological examination showed a typical subependymoma. A complete neurological recovery was achieved after surgery. Conclusions. Subependymomas are rare low-grade glial neoplasm that commonly arise in the ventricular system. They have a low-proliferative potential but in these locations they can cause symptomatic hydrocephalus. Surgical removal of the mass and the restoration of the normal cerebrospinal fluid pathways constitute the optimal management strategy (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Glioma Subependimal/cirurgia , Hidrocefalia/etiologia , Neoplasias do Ventrículo Cerebral/cirurgia , Glioma Subependimal/complicações , Derrame Subdural/cirurgia , Cefaleia/etiologia
7.
Rev. mex. pediatr ; 64(1): 25-8, ene.-feb. 1997. tab
Artigo em Espanhol | LILACS | ID: lil-225145

RESUMO

Se estudiaron 35 niños de escasos recursos económicos quienes, por padecer de insuficiencia renal crónica, fueron incorporados a un pograma de diálisis peritoneal intermitente hospitalaria, empleando un catéter tipo Tenckhoff; todos fueron atendidos por un mínimo de tres meses, con uno a tres internamientos por semana y manejo médico y dietético. Su promedio de edad fue de 11.8 años y el de tiempo en diálisis de 23 meses, con un máximo de cinco años y dos meses. Se emplearon entre uno y cinco catéteres por paciente, la complicación más frecuente fue la peritonitis que se presentó en 34 niños, con un episodio cada 6.2 meses/paciente. Se transfundieron 27 niños con un promedio de 8.2 transfusiones por cada uno. Al término del estudio, 11 pacientes seguían en tratamiento en el hospital, 14 se habían trasladado a otro hospital y siete habían fallecido. En contraste con decenios anteriores la sobrevida de estos pacientes ha mejorado, el grado de adaptación al programa es satisfactorio, aunque su rehabilitación, juzgándola por la práctica de actividades propias de su edad, es aún pobre


Assuntos
Humanos , Masculino , Feminino , Peritonite/complicações , Diálise Peritoneal/estatística & dados numéricos , Diálise Peritoneal/instrumentação , Diálise Peritoneal , Fatores Socioeconômicos , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/reabilitação , Insuficiência Renal Crônica/terapia
8.
Rev. mex. pediatr ; 62(2): 51-4, mar.-abr. 1995. tab
Artigo em Espanhol | LILACS | ID: lil-151374

RESUMO

Se estudiaron 114 niños con enuresis, a los que se les sometió estudios de examen general de orina y urocultivo. Los niños que presentaron bacteriuria, compatible con infección urinaria, se sometieron a estudios de cistograma miccional y de ultrasonido renal y de las vías urinarias. Los exámenes clínicos y de laboratorio no dieron datos de anormalidad en 109 niños; en cinco niñas se encontró evidencia de infección por E. coli, cuatro de ellas con síntomas clínicos compatibles con esta enfermedad. En ninguna de estas niñas se encontró alguna malformación de las vías urinarias que estuviese asociada a la infección, y ambos problemas con la enuresis. Se discuten estos hallazgos y se propone la secuencia de estudio, seguida en la investigación, para el manejo de los niños enuréticos


Assuntos
Criança , Adolescente , Humanos , Masculino , Feminino , Infecções Urinárias/diagnóstico , Ultrassonografia , Enurese/microbiologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/diagnóstico
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