RESUMO
Diethyldithiocarbamate (DDC) has been shown to enhance 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced striatal dopamine depletion in mice. Surprisingly, although DDC is a prototypic member of a class of compounds called dithiocarbamates (DTCs) that are widely used in industry and agriculture, only one study has investigated the interaction of dithiocarbamates other than DDC with MPTP. The purpose of the present study was to investigate whether two other widely used dithiocarbamates, ethylenebisdithiocarbamate (EBDC) and methyldithiocarbamate (MDC), would also enhance MPTP toxicity. The dithiocarbamates were administered to mice intraperitoneally at various doses with or without MPTP. Doses were chosen based on the LD50 values for each compound. DDC was also tested (using a previously reported dose) for comparison. Striata were obtained one week later for dopamine measurements. Consistent with previous reports, DDC produced statistically significant enhancement in MPTP-induced striatal dopamine depletion. EBDC also produced significant exacerbation of MPTP-induced dopamine depletion. In contrast to DDC and EBDC, MDC failed to enhance the effects of MPTP, even when administered at doses of high lethality. Further studies of the dithiocarbamate class of compounds may help to elucidate the mechanism of DDC and EBDC enhancement of MPTP toxicity. Given the widespread use of these compounds in the environment such studies may also provide clues to the process of nigrostriatal cell degeneration in Parkinson's disease.
Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Corpo Estriado/efeitos dos fármacos , Dopaminérgicos/farmacologia , Dopamina/metabolismo , Etilenobis (ditiocarbamatos)/farmacologia , Animais , Corpo Estriado/metabolismo , Sinergismo Farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doença de Parkinson/metabolismo , Praguicidas/farmacologia , Tiocarbamatos/farmacologiaRESUMO
Great progress has been made in controlling the symptom distress of dying patients. This article reviews some of these methods and examines some triggering events that should cause physicians to re-examine patients' goals and care.
Assuntos
Doença Crônica , Assistência Terminal/métodos , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Gerenciamento Clínico , Família/psicologia , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/prevenção & controle , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/prevenção & controle , Falência Hepática/complicações , Falência Hepática/prevenção & controle , Pneumopatias Obstrutivas/complicações , Pneumopatias Obstrutivas/prevenção & controle , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/prevenção & controle , Seleção de Pacientes , Qualidade de Vida , Assistência Terminal/psicologiaRESUMO
The advent of new USAF aircraft control concepts necessitates the investigation of muscle fatigue in complex dynamic environments. The Acceleration Effects Branch of the Aerospace Medical Research Laboratory at Wright-Patterson Air Force Base had undertaken such a study for evaluation of fatigue in lateral G environments. Investigation of the literature indicates that the Fast Fourier Transform (FFT) of the electromyogram (EMG) signal samples could be used to determine fatigue by analysis of the center frequencies and amplitudes of the sampled power spectra. Reproducibility of data, especially in a dynamic environment, proved to be a challenge. However, acquisition and processing of the EMG signal have been optimized to give consistently reproducible and useable data. The method of sampling data and its processing are discussed.