RESUMO
BACKGROUND: Peripheral nerve injury and bone lesions, well known leprosy complications, lead to deformities and incapacities. The phosphate-regulating gene with homologies to endopeptidase on the X chromosome (PHEX) encodes a homonymous protein (PHEX) implicated in bone metabolism. PHEX/PHEX alterations may result in bone and cartilage lesions. PHEX expression is downregulated by intracellular Mycobacterium leprae (M. leprae) in cultures of human Schwann cells and osteoblasts. M. leprae in vivo effect on PHEX/PHEX is not known. METHODS: Cross-sectional observational study of 36 leprosy patients (22 lepromatous and 14 borderline-tuberculoid) and 20 healthy volunteers (HV). The following tests were performed: PHEX flow cytometric analysis on blood mononuclear cells, cytokine production in culture supernatant, 25-hydroxyvitamin D (OHvitD) serum levels and (99m)Tc-MDP three-phase bone scintigraphy, radiography of upper and lower extremities and blood and urine biochemistry. RESULTS: Significantly lower PHEX expression levels were observed in lepromatous patients than in the other groups (χ(2) = 16.554, p < 0.001 for lymphocytes and χ(2) = 13.933, p = 0.001 for monocytes). Low levels of 25-(OHvitD) were observed in HV (median = 23.0 ng/mL) and BT patients (median = 27.5 ng/mL) and normal serum levels were found in LL patients (median = 38.6 ng/mL). Inflammatory cytokines, such as TNF, a PHEX transcription repressor, were lower after stimulation with M. leprae in peripheral blood mononuclear cells from lepromatous in comparison to BT patients and HV (χ(2) = 10.820, p < 0.001). CONCLUSION: Downregulation of PHEX may constitute an important early component of bone loss and joint damage in leprosy. The present results suggest a direct effect produced by M. leprae on the osteoarticular system that may use this mechanism.
Assuntos
Regulação para Baixo , Hanseníase Dimorfa/metabolismo , Hanseníase Multibacilar/metabolismo , Endopeptidase Neutra Reguladora de Fosfato PHEX/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Osso e Ossos/microbiologia , Cartilagem/microbiologia , Estudos Transversais , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Voluntários Saudáveis , Humanos , Inflamação/metabolismo , Inflamação/microbiologia , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Osteoblastos/microbiologia , Células de Schwann/microbiologia , Medronato de Tecnécio Tc 99m , Adulto JovemRESUMO
OBJECTIVE: To report the experience of the Brazilian Program of Pediatric Teleradiology in combining teleconferencing and a virtual learning environment for services integration, collaborative research, and continuing education in pediatric radiology. MATERIALS AND METHODS: We performed virtual meetings from March 2005 to October 2010 on pediatric radiology-related themes, using a combination of videoconferences and Web conferences, which were recorded and made available in an open-source software (Moodle) for reuse. RESULTS: We performed 58 virtual sessions: 29 anatomical-clinical-radiological sessions, 28 on upgrading themes, and 1 virtual symposium. The average of connected points was 12 by videoconference and 39 by Web conference, and of 450 participants per event. At the time of this writing, 318 physicians and students are registered in the virtual learning environment, with a total of 14,678 accesses. CONCLUSIONS: Telemedicine is being included in pediatric radiology practice, as a means for distance education, training, and continuing integration between groups.
