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1.
Braz J Med Biol Res ; 56: e12547, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36995873

RESUMO

The main goal of this study was to determine whether oxidative imbalance mediated by AT1 receptor (AT1R) is responsible for deleterious endothelial responses to mental stress (MS) in overweight/obese class I men. Fifteen overweight/obese men (27±7 years old; 29.8±2.6 kg/m2) participated in three randomized experimental sessions with oral administration of the AT1R blocker olmesartan (40 mg; AT1R blockade) or ascorbic acid (AA; 3g) infusion or placebo [both intravenously (0.9% NaCl) and orally]. After two hours, endothelial function was determined by flow-mediated dilation (FMD) before (baseline), 30 min (30MS), and 60 min (60MS) after a five-minute acute MS session (Stroop Color Word Test). Blood was collected before (baseline), during MS, and 60 min after MS for redox homeostasis profiling: lipid peroxidation (TBARS; thiobarbituric acid reactive species), protein carbonylation, and catalase activity by colorimetry and superoxide dismutase (SOD) activity by an ELISA kit. At the placebo session, FMD significantly decreased 30MS (P=0.05). When compared to baseline, TBARS (P<0.02), protein carbonylation (P<0.01), catalase (P<0.01), and SOD (P<0.01) increased during the placebo session. During AT1R blockade, FMD increased 30 min after MS (P=0.01 vs baseline; P<0.01 vs placebo), while AA infusion increased FMD only 60 min after MS. No differences were observed during MS with the AT1R blockade and AA regarding TBARS, protein carbonylation, catalase, and SOD. AT1R-mediated redox imbalances played an important role in endothelial dysfunction to mental stress.


Assuntos
Obesidade , Estresse Psicológico , Humanos , Estresse Psicológico/patologia , Células Endoteliais/patologia , Estresse Oxidativo , Masculino , Obesidade/complicações , Obesidade/metabolismo , Obesidade/patologia , Receptor Tipo 1 de Angiotensina/metabolismo
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;56: e12547, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1430021

RESUMO

The main goal of this study was to determine whether oxidative imbalance mediated by AT1 receptor (AT1R) is responsible for deleterious endothelial responses to mental stress (MS) in overweight/obese class I men. Fifteen overweight/obese men (27±7 years old; 29.8±2.6 kg/m2) participated in three randomized experimental sessions with oral administration of the AT1R blocker olmesartan (40 mg; AT1R blockade) or ascorbic acid (AA; 3g) infusion or placebo [both intravenously (0.9% NaCl) and orally]. After two hours, endothelial function was determined by flow-mediated dilation (FMD) before (baseline), 30 min (30MS), and 60 min (60MS) after a five-minute acute MS session (Stroop Color Word Test). Blood was collected before (baseline), during MS, and 60 min after MS for redox homeostasis profiling: lipid peroxidation (TBARS; thiobarbituric acid reactive species), protein carbonylation, and catalase activity by colorimetry and superoxide dismutase (SOD) activity by an ELISA kit. At the placebo session, FMD significantly decreased 30MS (P=0.05). When compared to baseline, TBARS (P<0.02), protein carbonylation (P<0.01), catalase (P<0.01), and SOD (P<0.01) increased during the placebo session. During AT1R blockade, FMD increased 30 min after MS (P=0.01 vs baseline; P<0.01 vs placebo), while AA infusion increased FMD only 60 min after MS. No differences were observed during MS with the AT1R blockade and AA regarding TBARS, protein carbonylation, catalase, and SOD. AT1R-mediated redox imbalances played an important role in endothelial dysfunction to mental stress.

3.
Braz J Med Biol Res ; 55: e12110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35703682

RESUMO

In preparation for tracheal intubation during induction of anesthesia, the patient may be ventilated with 100% oxygen. To investigate the impact of acute isocapnic hyperoxia on endothelial activation and vascular remodeling, ten healthy young men (24±3 years) were exposed to 5-min normoxia (21% O2) and 10-min hyperoxia trials (100% O2). During hyperoxia, intercellular adhesion molecules (ICAM-1) (hyperoxia: 4.16±0.85 vs normoxia: 3.51±0.84 ng/mL, P=0.04) and tissue inhibitor matrix metalloproteinase 1 (TIMP-1) (hyperoxia: 8.40±3.84 vs normoxia: 5.73±2.15 pg/mL, P=0.04) increased, whereas matrix metalloproteinase (MMP-9) activity (hyperoxia: 0.53±0.11 vs normoxia: 0.68±0.18 A.U., P=0.03) decreased compared to the normoxia trial. We concluded that even short exposure to 100% oxygen may affect endothelial activation and vascular remodeling.


Assuntos
Hiperóxia , Moléculas de Adesão Celular , Humanos , Masculino , Oxigênio , Consumo de Oxigênio/fisiologia , Remodelação Vascular
4.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;55: e12110, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384141

RESUMO

In preparation for tracheal intubation during induction of anesthesia, the patient may be ventilated with 100% oxygen. To investigate the impact of acute isocapnic hyperoxia on endothelial activation and vascular remodeling, ten healthy young men (24±3 years) were exposed to 5-min normoxia (21% O2) and 10-min hyperoxia trials (100% O2). During hyperoxia, intercellular adhesion molecules (ICAM-1) (hyperoxia: 4.16±0.85 vs normoxia: 3.51±0.84 ng/mL, P=0.04) and tissue inhibitor matrix metalloproteinase 1 (TIMP-1) (hyperoxia: 8.40±3.84 vs normoxia: 5.73±2.15 pg/mL, P=0.04) increased, whereas matrix metalloproteinase (MMP-9) activity (hyperoxia: 0.53±0.11 vs normoxia: 0.68±0.18 A.U., P=0.03) decreased compared to the normoxia trial. We concluded that even short exposure to 100% oxygen may affect endothelial activation and vascular remodeling.

5.
Rev Neurol ; 72(5): 151-156, 2021 Mar 01.
Artigo em Espanhol | MEDLINE | ID: mdl-33616197

RESUMO

INTRODUCTION: The Wada test consists of the selective and reversible inhibition of a cerebral hemisphere by intracarotid injection of amobarbital in order to evaluate the laterality of language and memory. However, there are other anesthetic drugs such as propofol, as an alternative for the test. OBJECTIVE: The objective of the study was to describe the tolerability and adverse effects (AE) of the use of propofol for the Wada test, during the presurgical study of patients with drug-resistant epilepsy. METHODS: Consecutive patients with a diagnosis of drug-resistant structural epilepsy were selected who underwent the Wada test during the pre-surgical study in the period from June 2012 to May 2019. The patients were retrospectively evaluated. The AE were described according to the Mikuni classification, modified by Curot. The variables of sex, age, epileptic foci laterality, language laterality, lesional substrate, etiology and dose of administered Propofol were analyzed for any statistical significance. RESULTS: A total of 74 patients, 40 men (54%), were studied. Forty-seven patients (63.5%) had at least one AE. The mean dose of propofol was 9.23 mg. The most frequent AE were tearing, sweating and red eye, corresponding to group I (57%). One patient developed convulsive status epilepticus, an important AE not previously described during the Wada test. CONCLUSION: Performing the Wada test with propofol causes frequent mild adverse effects, which do not prevent its completion. We describe a case of convulsive status epilepticus as the only serious AE.


TITLE: Tolerabilidad y efectos adversos del propofol en la prueba de Wada.Introducción. La prueba de Wada consiste en la inhibición selectiva y reversible de un hemisferio cerebral mediante la inyección intracarotídea de amobarbital con el objetivo de evaluar la lateralidad del lenguaje y la memoria. Existen otros fármacos anestésicos, como el propofol, como alternativa para la prueba. Objetivo. El objetivo del estudio fue describir la tolerabilidad y los efectos adversos (EA) del uso de propofol para la prueba de Wada durante el estudio prequirúrgico de pacientes con epilepsia farmacorresistente. Pacientes y métodos. Se seleccionó a pacientes con diagnóstico de epilepsia estructural farmacorresistente consecutivos, quienes se sometieron a la prueba de Wada durante el estudio prequirúrgico en el período de junio de 2012 a mayo de 2019. Los pacientes fueron evaluados de manera retrospectiva. Los EA se describieron según la clasificación de Mikuni, modificada por Curot. Se analizaron las variables de sexo, edad, lateralidad del foco epiléptico, lateralidad del lenguaje, sustrato lesional, etiología y dosis de propofol administrada en busca de significación estadística. Resultados. Se estudió a un total de 74 pacientes, de los cuales 40 eran hombres (54%). Cuarenta y siete pacientes (63,5%) tuvieron al menos un EA. La dosis media de propofol fue de 9,23 mg. Los EA más frecuentes fueron lagrimeo, sudoración y ojo rojo, correspondientes al grupo I (57%). Un paciente desarrolló estado epiléptico convulsivo, EA importante no descrito anteriormente durante la prueba de Wada. Conclusión. La realización de la prueba de Wada con propofol ocasiona frecuentes efectos adversos leves, los cuales no impiden su finalización. Describimos un caso de estado epiléptico convulsivo como único EA grave.


Assuntos
Anestésicos Intravenosos/efeitos adversos , Testes Neuropsicológicos , Propofol/efeitos adversos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
7.
Rehabil Res Pract ; 2018: 5798265, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29850254

RESUMO

OBJECTIVE: This study investigated the acute residual effects induced by different frequencies of whole-body vibration (WBV) on postural control of elderly women. DESIGN: Thirty physically active elderly women (67 ± 5 years) were randomly divided into three groups: two experimental groups (high WBV frequency: 45 Hz and 4 mm amplitude, n = 10; low WBV frequency: 30 Hz and 4 mm amplitude, n = 10) and one control group (n = 10), with no treatment. The participants were first subjected to stabilometry tests and were then guided through three sets of isometric partial squats for 60 s while the WBV stimulation was applied. The control group was subjected to the same conditions but without the WBV stimulation. The participants were again subjected to body balance tests immediately following the end of the intervention period and again at 8, 16, and 24 min. To measure body sway control, three 60 s tests were performed at 10 s intervals for each of the following experimental conditions: (1) eyes opened and (2) eyes closed. The following variables were investigated: the average velocity of the displacement of the centre of pressure in the anterior-posterior and medial-lateral planes as well as in the elliptical area. RESULTS: A 3 (condition) × 5 (test) two-way repeated-measures ANOVA did not identify significant differences in the stabilometric variables, regardless of group, time, or experimental condition. CONCLUSIONS: The effect of WBV, regardless of the stimulation frequency, did not have a significant effect immediately after or up to 24 minutes after vibration cessation, on the variables involved in the control of postural stability in physically active elderly women.

8.
Braz. j. biol ; Braz. j. biol;68(4,supl): 1025-1037, Nov. 2008. graf, tab, ilus
Artigo em Inglês | LILACS | ID: lil-504455

RESUMO

The present study deals with the ecological impacts of the introduction of two alien species of piscivorous fish in several lakes of the Middle Rio Doce lake district in Minas Gerais, Brazil. It was demonstrated that these effects were not restricted only to the fish community. The introduction of the predatory red piranha Pygocentrus nattereri and the tucunaré Cichla cf. ocellaris caused not only a sharp decrease in the number of native fish species, but also major shifts in other trophic levels. Just after the fish were introduced, most lakes began to show conspicuous changes in phytoplankton species composition, in which Cyanophyceae gradually came to dominate. The zooplankton community lost several species, and in some cases, such as Lake Carioca, all the cladoceran species disappeared. On the other hand, invertebrate predators, represented by the dipteran Chaoboridae, boomed in the lake, with higher densities of exotic species, probably as a result of the "ecological release" by reduction of the original fish fauna. There was a general trend of species loss in different trophic levels. All these changes are apparently associated with decreases in water quality. The present situation in these lakes demands new approaches to the management and conservation of these ecosystems.


O presente estudo trata dos impactos ecológicos da introdução de duas espécies invasoras de peixes piscívoros em diversos lagos da região lacustre do médio rio Doce em Minas Gerais, Brasil. Demonstrou-se que estes efeitos não se restringiram às comunidade de peixes. A introdução dos predadores Pygocentrus nattereri (piranha-vermelha) e Cichla cf. ocelaris (tucunaré) não só causou uma forte redução no número de espécies de peixes nativos, como também mudanças nos níveis tróficos inferiores. Pouco depois das introduções, a maioria dos lagos começou a mostrar alterações na comunidade fitoplanctônica, tais como o aparecimento da dominância de Cyanophyceae. A comunidade zooplanctônica perdeu diversas espécies e, em alguns casos, houve o desaparecimento de todas as espécies de cladóceros limnéticos, como é o caso da lagoa Carioca. Por outro lado, predadores invertebrados, representados pelos dípteros da família Chaoboridae, floresceram nos lagos com maiores densidades de espécies exóticas de peixes, provavelmente como resultado da "liberação ecológica" causada pela redução da ictiofauna original. Além de uma tendência geral de perda de espécies em diferentes níveis tróficos, outras mudanças estão aparentemente associadas com a redução da qualidade de água. Dessa forma, esses ecossistemas estão necessitando urgentemente de novas abordagens nas estratégias de manejo e conservação.


Assuntos
Animais , Peixes/classificação , Plâncton/química , Comportamento Predatório/fisiologia , Clima Tropical , Biodiversidade , Biomassa , Brasil , Conservação dos Recursos Naturais , Eutrofização , Cadeia Alimentar , Água Doce , Fitoplâncton/classificação , Estações do Ano , Zooplâncton/classificação
9.
Braz J Biol ; 68(4 Suppl): 1025-37, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19197473

RESUMO

The present study deals with the ecological impacts of the introduction of two alien species of piscivorous fish in several lakes of the Middle Rio Doce lake district in Minas Gerais, Brazil. It was demonstrated that these effects were not restricted only to the fish community. The introduction of the predatory red piranha Pygocentrus nattereri and the tucunaré Cichla cf. ocellaris caused not only a sharp decrease in the number of native fish species, but also major shifts in other trophic levels. Just after the fish were introduced, most lakes began to show conspicuous changes in phytoplankton species composition, in which Cyanophyceae gradually came to dominate. The zooplankton community lost several species, and in some cases, such as Lake Carioca, all the cladoceran species disappeared. On the other hand, invertebrate predators, represented by the dipteran Chaoboridae, boomed in the lake, with higher densities of exotic species, probably as a result of the 'ecological release' by reduction of the original fish fauna. There was a general trend of species loss in different trophic levels. All these changes are apparently associated with decreases in water quality. The present situation in these lakes demands new approaches to the management and conservation of these ecosystems.


Assuntos
Peixes/classificação , Plâncton/química , Comportamento Predatório/fisiologia , Clima Tropical , Animais , Biodiversidade , Biomassa , Brasil , Conservação dos Recursos Naturais , Eutrofização , Cadeia Alimentar , Água Doce , Fitoplâncton/classificação , Estações do Ano , Zooplâncton/classificação
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