RESUMO
Malignant hyperthermia (MH) is a pharmacogenetic disease triggered by volatile anesthetics and succinylcholine. Deaths due to MH have been reported in Brazil. The first Malignant Hyperthermia Diagnostic and Research Center in Latin America was inaugurated in 1993 at the Federal University of Rio de Janeiro, Brazil. The center followed the diagnostic protocols of the North America MH Group, in which the contractures of biopsies from the vastus lateralis muscle are analyzed after exposure to caffeine and halothane (CHCT). CHCT was performed in individuals who survived, their relatives and those with signs/symptoms somewhat related to MH susceptibility (MHS). Here, we report data from 194 patients collected over 16 years. The Southeast (N = 110) and South (N = 71) represented the majority of patients. Median age was 25 (4-70) years, with similar numbers of males (104) and females (90). MHS was found in 90 patients and 104 patients were normal. Abnormal responses to both caffeine and halothane were observed in 59 patients and to caffeine or halothane in 20 and 11 patients, respectively. The contracture of biopsies from MHS exposed to caffeine and halothane was 1.027 ± 0.075 g (N = 285) and 4.021 ± 0.255 g (N = 226), respectively. MHS was found in patients with either low or high blood creatine kinase and also, with a low score on the clinical grading scale. Thus, these parameters cannot be used with certainty to predict MHS. We conclude that the CHCT protocol described by the North America MH Group contributed to identification of MHS in suspected individuals at an MH center in Brazil with 100 percent sensitivity and 65.7 percent specificity.
Assuntos
Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Anestésicos Inalatórios , Cafeína , Contratura/induzido quimicamente , Halotano , Hipertermia Maligna/diagnóstico , Biópsia , Contratura/fisiopatologia , Hipertermia Maligna/fisiopatologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Adulto JovemRESUMO
Malignant hyperthermia (MH) is a pharmacogenetic disease triggered by volatile anesthetics and succinylcholine. Deaths due to MH have been reported in Brazil. The first Malignant Hyperthermia Diagnostic and Research Center in Latin America was inaugurated in 1993 at the Federal University of Rio de Janeiro, Brazil. The center followed the diagnostic protocols of the North America MH Group, in which the contractures of biopsies from the vastus lateralis muscle are analyzed after exposure to caffeine and halothane (CHCT). CHCT was performed in individuals who survived, their relatives and those with signs/symptoms somewhat related to MH susceptibility (MHS). Here, we report data from 194 patients collected over 16 years. The Southeast (N = 110) and South (N = 71) represented the majority of patients. Median age was 25 (4-70) years, with similar numbers of males (104) and females (90). MHS was found in 90 patients and 104 patients were normal. Abnormal responses to both caffeine and halothane were observed in 59 patients and to caffeine or halothane in 20 and 11 patients, respectively. The contracture of biopsies from MHS exposed to caffeine and halothane was 1.027 +/- 0.075 g (N = 285) and 4.021 +/- 0.255 g (N = 226), respectively. MHS was found in patients with either low or high blood creatine kinase and also, with a low score on the clinical grading scale. Thus, these parameters cannot be used with certainty to predict MHS. We conclude that the CHCT protocol described by the North America MH Group contributed to identification of MHS in suspected individuals at an MH center in Brazil with 100% sensitivity and 65.7% specificity.
Assuntos
Anestésicos Inalatórios , Cafeína , Contratura/induzido quimicamente , Halotano , Hipertermia Maligna/diagnóstico , Adolescente , Adulto , Idoso , Biópsia , Criança , Pré-Escolar , Contratura/fisiopatologia , Feminino , Humanos , Masculino , Hipertermia Maligna/fisiopatologia , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Adulto JovemRESUMO
The purpose of this study was to determine whether decreased oxidative stress would increase the resistance to cardiac contracture induced by H(2)O(2) in hypothyroid rats. Male Wistar rats were divided into two groups: control and hypothyroid. Hypothyroidism was induced via thyroidectomy. Four weeks post surgery, blood samples were collected to perform thyroid hormone assessments, and excised hearts were perfused at a constant flow with or without H(2)O(2) (1 mmol/L), being divided into two sub-groups: control, hypothyroid, control + H(2)O(2), hypothyroid + H(2)O(2). Lipid peroxidation (LPO) was evaluated by chemiluminescence (CL) and thiobarbituric acid reactive substances (TBARS) methods, and protein oxidation by carbonyls assay in heart homogenates. Cardiac tissue was also screened for superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, and for total radical-trapping antioxidant potential (TRAP). Analyses of SOD and glutathione-S-transferase (GST) protein expression were also performed in heart homogenates. Hypothyroid hearts were found to be more resistant to H(2)O(2)-induced contracture (60% elevation in LVEDP) as compared to control. CL, TBARS, carbonyl, as well as SOD, CAT, GPx activities and TRAP levels were reduced (35, 30, 40, 30, 16, 25, and 33%, respectively) in the cardiac homogenates of the hypothyroid group as compared to controls. A decrease in SOD and GST protein levels by 20 and 16%, respectively, was also observed in the hypothyroid group. These results suggest that a hypometabolic state caused by thyroid hormone deficiency can lead to an improved response to H(2)O(2) challenge and is associated with decreased oxidative myocardial damage.
Assuntos
Contratura/metabolismo , Peróxido de Hidrogênio/farmacologia , Hipotireoidismo/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Catalase/metabolismo , Contratura/induzido quimicamente , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos , Masculino , Carbonilação Proteica , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismoRESUMO
La melatonina es el principal indol secretado por la glándula pineal.Además de su efecto antigonadotrófico, se han descrito diversos efectos fisiológicos no hormonales. Entre estos se han reportado la inhibición de la contracción de tejidos con musculatura lisa, aunque este efecto se ha sido descrito ampliamente. El presente estudio se realizó con el propósito de caracterizar el efecto de la melatonina sobre la contracción uterina inducida por carbacol. Se realizó un estudio in vitro empleando úteros de ratas estrogenizadas de la cepa Wistar. La contracción fue producida por carbacol en un rango de concentración de 5 x 10 a 10 M/ml, en ausencia y presencia de melatonina. De ésta se emplearon las siguientes concentraciones: 10, 2.5 x 10 M/ml. Los resultados obtenidos muestran que la concentración efectiva media de carbacol para inducir contracción uterina se incrementa significativamente en precencia de melatonina a las concentraciones de 10 y 10 M/ml. Las curvas log de la concentración- porcentaje de contracción máxima para carbacol en presencia de melatonina se desplazan a la derecha de la curva de carbacol en ausencia de melatonia. Se concluye que la melatonina inhibe la contracción producida por carbacol de manera dependiente de la concentración, comportándose como una antagonista fisiológico.
Assuntos
Animais , Ratos , Carbacol/farmacologia , Contratura/induzido quimicamente , Melatonina/farmacologia , Ocitocina/fisiologia , Útero , Carbacol/metabolismo , Contratura/metabolismo , Melatonina/fisiologia , Ocitocina/farmacologiaRESUMO
Chronic arsenic poisoning is an uncommon cause of peripheral neuropathy in Jamaica. A patient with this disorder is described. The insidious nature of chronic arsenic poisoning, with its disabling complications, is emphasised.