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1.
Sci Rep ; 11(1): 7197, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785780

RESUMO

Cell migration is a dynamic process that involves adhesion molecules and the deformation of the moving cell that depends on cytoskeletal remodeling and actin-modulating proteins such as myosins. In this work, we analyzed the role of the class I Myosin-1 g (Myo1g) in migratory processes of LPS + IL-4 activated B lymphocytes in vivo and in vitro. In vivo, the absence of Myo1g reduced homing of activated B lymphocytes into the inguinal lymph node. Using microchannel chambers and morphology analysis, we found that the lack of Myo1g caused adhesion and chemotaxis defects. Additionally, deficiency in Myo1g causes flaws in adopting a migratory morphology. Our results highlight the importance of Myo1g during B cell migration.


Assuntos
Linfócitos B/imunologia , Linfonodos/imunologia , Ativação Linfocitária , Antígenos de Histocompatibilidade Menor/imunologia , Miosinas/imunologia , Animais , Linfócitos B/citologia , Adesão Celular , Movimento Celular , Células Cultivadas , Feminino , Camundongos Endogâmicos C57BL
4.
Appl Biochem Biotechnol ; 178(8): 1522-33, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26728653

RESUMO

The effect of natural mineral on the mono-digestion of maize straw was evaluated in continuously stirred tank reactors (CSTRs) at 38 °C. Different strategies of mineral addition were studied. The organic loading rate (OLR) was varied from 0.5 to 2.5 g volatile solid (VS) L(-1) d(-1). A daily addition of 1 g mineral L(-1) in reactor 2 (R2) diminished the methane production by about 11 % with respect to the initial phase. However, after a gradual addition of mineral, an average methane yield of 257 NmL CH4 g VS(-1) was reached and the methane production was enhanced by 30 % with regard to R1. An increase in the frequency of mineral addition did not enhance the methane production. The archaeal community was more sensitive to the mineral than the bacterial population whose similarity stayed high between R1 and R2. Significant difference in methane yield was found for both reactors throughout the operation.


Assuntos
Reatores Biológicos , Metano/biossíntese , Zea mays , Archaea/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Metano/química , Minerais/química , Minerais/farmacologia , Resíduos
5.
IEEE Trans Biomed Eng ; 63(2): 250-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26258928

RESUMO

Our aim was to compare the different methods of modeling the effect of circulating blood flow on the thermal lesion dimensions created by radio frequency (RF) cardiac ablation and on the maximum blood temperature. Computational models were built to study the temperature distributions and lesion dimensions created by a nonirrigated electrode by two RF energy delivery protocols (constant voltage and constant temperature) under high and low blood flow conditions. Four methods of modeling the effect of circulating blood flow on lesion dimensions and temperature distribution were compared. Three of them considered convective coefficients at the electrode-blood and tissue-blood interfaces to model blood flow: 1) without including blood as a part of the domain; 2) constant electrical conductivity of blood; and 3) temperature-dependent electrical conductivity of blood (+2%/°C). Method 4) included blood motion and was considered to be a reference method for comparison purposes. Only Method 4 provided a realistic blood temperature distribution. The other three methods predicted lesion depth values similar to those of the reference method (differences smaller than 1 mm), regardless of ablation mode and blood flow conditions. Considering the aspects of lesion size and maximum temperature reached in blood and tissue, Method 2 seems to be the most suitable alternative to Method 4 in order to reduce the computational complexity. Our findings could have an important implication in future studies of RF cardiac ablation, in particular, in choosing the most suitable method to model the thermal effect of circulating blood.


Assuntos
Ablação por Cateter/métodos , Simulação por Computador , Hemodinâmica/fisiologia , Modelos Cardiovasculares , Fenômenos Fisiológicos Sanguíneos , Ablação por Cateter/efeitos adversos , Condutividade Elétrica , Humanos , Temperatura
6.
Neurología (Barc., Ed. impr.) ; 30(2): 83-89, mar. 2015. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-134166

RESUMO

Introducción: La migraña es un trastorno común y prevalente que contribuye considerablemente al gasto sanitario e interfiere en la calidad de vida de los pacientes. Nuestro objetivo fue explorar el nivel de estrés en el trabajo en una muestra de migrañosos y su posible asociación con la cronicidad del proceso Material y métodos: Se aplicó el test de Maslach («burnout inventory»: 22 ítems agrupados en bloques que valoran: agotamiento emocional [AE], realización personal [RP], despersonalización en el trabajo [DP]) e influencia positiva (IP) a 94 sujetos consecutivos reclutados en consultas. Las diferencias se compararon entre grupos clínicos (migraña crónica [MC] -más de 15 días/mes de cefalea/3 meses- vs. migraña episódica [ME] -< 15 días/mes-) mediante el modelo lineal general ajustado por edad y MIDAS. Resultados: La edad media fue superior en MC. Las puntuaciones medias en la escala MIDAS fueron 51 ± 4,1 en MC y 17,7 ± 15 en ME (p = 0,001). La media ajustada de AE fue en ME 24,6 ± 2,6, en MC 16,2 ± 2,6 y en controles 13,4 ± 2,3 (p = 0,03). La escala MIDAS se correlacionó inversamente con RP (p < 0,05). Discusión: Nuestros resultados señalan que el nivel de AE es mayor en ME que en MC; mientras la RP es peor cuanto mayor impacto tiene la migraña según escala MIDAS. La escala Maslach es una herramienta potencialmente útil en el estudio de las repercusiones de la migraña. Sorprendentemente, el AE es mayor en pacientes con menos crisis, lo que podría relacionarse con mecanismos de adaptación al estrés presentes en el paciente crónico


Introduction: Migraine is a common and prevalent disease that contributes to health expenditure and interferes with quality of life. Our goal was to analyse the level of stress at work in a sample of migraine and its possible association with the chronicity of the process Material and methods: We applied the Maslach Burnout Inventory, consisting of 22 items grouped into blocks that assess emotional exhaustion (EE), personal accomplishment (PA), depersonalisation at work (DP)] and positive influence (PI), to 94 consecutive subjects recruited in the outpatient clinic. Differences were compared between clinical groups (chronic migraine [CM]: > 15 days/month with headache over a 3-month period vs episodic migraine [EM]: < 15 days/month with headache) using the general linear model adjusted for age and MIDAS score Results: The mean age was higher in the CM group. Mean MIDAS scores were 51 ± 4.1 in CM, and 17.7 ± 15 in EM (P=.001). Adjusted means for EE were 24.6 ± 2.6 in CM patients, 16.2 ± 2.6 in EM patients, and 13.4 ± 2.3 (P=.03) in the healthy group. MIDAS scale scores were inversely correlated to PA (P < .05). Discussion: Our results suggest that the level of EE at work is higher in EM than in CM patients, while PA levels decrease as impact on the MIDAS scale increases. The Maslach scale is a potentially useful tool for studying migraine impact. Surprisingly, EE is higher in patients with fewer episodes; this tendency could be related to stress adaptation mechanisms present in patients with chronic illness


Assuntos
Humanos , Masculino , Feminino , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/epidemiologia , Fadiga , Esgotamento Profissional , Monitoramento Epidemiológico/tendências , Qualidade de Vida , Espanha/epidemiologia
7.
Neurologia ; 30(2): 83-9, 2015 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-24332784

RESUMO

INTRODUCTION: Migraine is a common and prevalent disease that contributes to health expenditure and interferes with quality of life. Our goal was to analyse the level of stress at work in a sample of migraine and its possible association with the chronicity of the process MATERIAL AND METHODS: We applied the Maslach Burnout Inventory, consisting of 22 items grouped into blocks that assess emotional exhaustion (EE), personal accomplishment (PA), depersonalisation at work (DP)] and positive influence (PI), to 94 consecutive subjects recruited in the outpatient clinic. Differences were compared between clinical groups (chronic migraine [CM]: > 15 days/month with headache over a 3-month period vs episodic migraine [EM]: < 15 days/month with headache) using the general linear model adjusted for age and MIDAS score RESULTS: The mean age was higher in the CM group. Mean MIDAS scores were 51 ± 4.1 in CM, and 17.7 ± 15 in EM (P=.001). Adjusted means for EE were 24.6 ± 2.6 in CM patients, 16.2 ± 2.6 in EM patients, and 13.4 ± 2.3 (P=.03) in the healthy group. MIDAS scale scores were inversely correlated to PA (P<.05) DISCUSSION: Our results suggest that the level of EE at work is higher in EM than in CM patients, while PA levels decrease as impact on the MIDAS scale increases. The Maslach scale is a potentially useful tool for studying migraine impact. Surprisingly, EE is higher in patients with fewer episodes; this tendency could be related to stress adaptation mechanisms present in patients with chronic illness.


Assuntos
Esgotamento Profissional/complicações , Emprego/psicologia , Transtornos de Enxaqueca/psicologia , Estresse Psicológico/complicações , Adulto , Doença Crônica , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/complicações , Qualidade de Vida
8.
Artigo em Inglês | MEDLINE | ID: mdl-22255919

RESUMO

Although some types of bipolar electrodes have been broadly employed in clinical practice to coagulate biological tissue by means of radiofrequency (RF) currents, there is still scanty available information about their electrical-thermal behaviour. We are focused on internally cooled bipolar electrodes. The goal of our study was to know more about the behavior of this kind of electrodes. For that, we planned an experimental and theoretical model. The experimental study was based on bovine hepatic ex vivo tissue and the theoretical model was based on the Finite Element Method (FEM). In order to check the feasibility of the theoretical model, we assessed both theoretically and experimentally the effect of the internal cooling characteristics of the bipolar electrode (flow rate and coolant temperature) on the impedance progress during RF heating and coagulation zone dimensions. The experimental and theoretical results were in good agreement, which suggests that the theoretical model could be useful to improve the design of cooled bipolar electrodes.


Assuntos
Eletrocoagulação/métodos , Animais , Ablação por Cateter/métodos , Bovinos , Simulação por Computador , Condutividade Elétrica , Impedância Elétrica , Eletrodos , Desenho de Equipamento , Análise de Elementos Finitos , Temperatura Alta , Fotocoagulação a Laser , Fígado/metabolismo , Modelos Teóricos , Ondas de Rádio , Temperatura , Fatores de Tempo
9.
Artigo em Inglês | MEDLINE | ID: mdl-22254312

RESUMO

The Cool-tip is one of the most widely employed electrodes in radiofrequency (RF) ablation (RFA) of hepatic tumors. This electrode creates reliable geometry and coagulation zones. Despite the advantages of this electrode, during the ablation is produced a phenomenon called roll-off in which impedance increases, energy deposition completely stops and the lesion size cannot be increased. Consequently, the thermal lesion size is smaller and the tumors which can be ablated are smaller too. In this research we studied theoretical and experimentally the electrical-thermal performance of the Cool-tip electrode during RFA of hepatic tissue. Mainly, we were interested in the occurrence of the roll-off and its relationship with the tissue temperatures around the electrode. The theoretical model included the vaporization of the tissue and the variation of the thermal and electrical conductivities with temperature. The model was solved numerically using COMSOL Multiphysics software. For the experimental part we conducted a study in ex vivo liver tissue. The experimental and theoretical results showed that the roll-off is totally related when temperatures around 100 °C surrounds the tissue close to the center of the Cool-tip. The knowledge of this fact brings a powerful tool to analyze alternative methods or techniques to avoid the roll-off.


Assuntos
Ablação por Cateter/instrumentação , Ablação por Cateter/métodos , Eletrodos , Hepatectomia/métodos , Fígado/patologia , Fígado/cirurgia , Modelos Biológicos , Animais , Temperatura Baixa , Simulação por Computador , Cirurgia Assistida por Computador/métodos , Suínos
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