RESUMO
The clinical spectrum of leprosy is related to patients' immune responses. Non-responsiveness towards Mycobacterium leprae (ML) seems to correlate with a Th2 cytokine profile. The reason for such a polarized immune response remains unclear. The C-type lectin, DC-SIGN, expressed by subsets of dendritic cells (DCs) and macrophages, has previously been associated with Th2 responses. Here we show abundant DC-SIGN expression in lepromatous but not borderline tuberculoid leprosy, in both HIV-positive and HIV-negative patients. Moreover, we demonstrate that DC-SIGN can act as an entry receptor for ML, as it does for M. tuberculosis, through the cell wall component lipoarabinomannan. DC-SIGN is expressed on virtually all ML-containing cells, providing further evidence for its role as a receptor. DC-SIGN may therefore be induced on macrophages in lepromatous leprosy and may then contribute to mycobacterial entry into these cells.
Assuntos
Moléculas de Adesão Celular/imunologia , Lectinas Tipo C/imunologia , Hanseníase/imunologia , Receptores de Superfície Celular/imunologia , Células Th2/imunologia , Adulto , Antígenos de Bactérias/imunologia , Linhagem Celular , Meios de Cultura , Feminino , Soronegatividade para HIV/imunologia , Soropositividade para HIV/imunologia , Humanos , Hanseníase Dimorfa/imunologia , Hanseníase Tuberculoide/imunologia , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/imunologia , Mycobacterium tuberculosis/imunologia , Transfecção/métodosAssuntos
Testes Diagnósticos de Rotina , Resistência a Meticilina , Procedimentos Ortopédicos , Cuidados Pré-Operatórios , Staphylococcus aureus/isolamento & purificação , Infecção da Ferida Cirúrgica/prevenção & controle , Adulto , Portador Sadio , Procedimentos Cirúrgicos Eletivos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Staphylococcus aureus/efeitos dos fármacos , País de GalesRESUMO
This paper describes approaches to longitudinal studies of the changes in the health status of the US astronauts. The methods include acquisition and analysis of biomedical data accumulated in one and repeated space missions, detection of potential occupational diseases inflight and evaluation of mortality cases associated with them. It is suggested to use pilots and flight controllers as controls. It is indicated that annual physical examinations can be an important source of relevant scientific information.
Assuntos
Voo Espacial , Adulto , Pressão Sanguínea , Peso Corporal , Feminino , Órgãos Governamentais , Humanos , Estudos Longitudinais , Masculino , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Pesquisa , Risco , Voo Espacial/instrumentação , Fatores de Tempo , Estados UnidosRESUMO
Clinical data collected from a 15-year study of the homogeneous group of pre-Shuttle astronauts have revealed no significant long-term effects from spaceflight. The current hypothesis suggests that repeated exposures to the space environment in the Shuttle era will similarly have no long-term health effects. However, a much more heterogeneous group of astronauts and non-astronaut scientists will fly in Shuttle, and data on this group's adaptation to the space environment and readaptation to Earth are currently sparse. In addition, very little information is available concerning the short- and long-term medical consequences of long duration exposure to space and subsequent readaptation to the Earth environment. In this paper, retrospective clinical information on astronauts is reviewed and concepts for conducting epidemiological studies examining long-term health effects of spaceflight on humans, including associated occupational risks factors, are presented.
