RESUMEN
This case is, to the authors' knowledge, the first reported case in the literature of bilateral orbital abscesses as result of an infected nasal dermoid. The baby presented with what proved to be bilateral supraorbital subperiosteal abscesses with associated frontal osteitis/osteomyelitis and soft tissue infection of the glabella. Methicillin-sensitive staphylococcus aureus infection was found in the setting of a midline nasal dermoid with tuft of hair and infected sinus tract that was at least initially missed on diagnosis.
Asunto(s)
Absceso/etiología , Coristoma/complicaciones , Quiste Dermoide/complicaciones , Infecciones Bacterianas del Ojo/etiología , Cabello , Enfermedades Nasales/complicaciones , Infecciones Estafilocócicas/etiología , Absceso/diagnóstico , Absceso/microbiología , Coristoma/diagnóstico , Quiste Dermoide/diagnóstico , Infecciones Bacterianas del Ojo/diagnóstico , Infecciones Bacterianas del Ojo/microbiología , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Enfermedades Nasales/diagnóstico , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/aislamiento & purificación , Tomografía Computarizada por Rayos XRESUMEN
Receptors for advanced glycation end-products (RAGE) are members of the immunoglobulin superfamily of cell-surface receptors implicated in mechanisms of pulmonary inflammation. In the current study, we test the hypothesis that RAGE mediates inflammation in primary alveolar macrophages (AMs) exposed to diesel particulate matter (DPM). Quantitative RT-PCR and immunoblotting revealed that RAGE was up-regulated in Raw264.7 cells, an immortalized murine macrophage cell line and primary AMs exposed to DPM for 2 h. Because DPM increased RAGE expression, we exposed Raw264.7 cells and primary AMs isolated from RAGE null and wild-type (WT) mice to DPM prior to the assessment of inflammatory signaling intermediates. DPM led to the activation of Rat sarcoma GTPase (Ras), p38 MAPK and NF-κB in WT AMs and, when compared to WT AMs, these intermediates were diminished in DPM-exposed AMs isolated from RAGE null mice. Furthermore, cytokines implicated in inflammation, including IL-4, IL-12, IL-13 and TNFα, were all significantly decreased in DPM-exposed RAGE null AMs compared to similarly exposed WT AMs. These results demonstrate that diesel-induced inflammatory responses by primary AMs are mediated, at least in part, via RAGE signaling mechanisms. Further work may show that RAGE signaling in both alveolar epithelial cells and resident macrophages is a potential target in the treatment of inflammatory lung diseases exacerbated by environmental pollution.
Asunto(s)
Contaminantes Atmosféricos/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Pulmón/metabolismo , Macrófagos Alveolares/metabolismo , Receptores Inmunológicos/biosíntesis , Transducción de Señal/efectos de los fármacos , Emisiones de Vehículos/toxicidad , Animales , Línea Celular , Citocinas/biosíntesis , Citocinas/genética , Regulación de la Expresión Génica/genética , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Pulmón/patología , Macrófagos Alveolares/patología , Ratones , Ratones Mutantes , Receptor para Productos Finales de Glicación Avanzada , Receptores Inmunológicos/genética , Transducción de Señal/genéticaRESUMEN
BACKGROUND: Receptors for advanced glycation end-products (RAGE) are immunoglobulin-like pattern recognition receptors abundantly localized to lung epithelium. Our research demonstrated that primary tobacco smoke exposure increases RAGE expression and that RAGE partly mediates pro-inflammatory signaling during exposure. However, the degree to which RAGE influences developing lungs when gestating mice are exposed to secondhand smoke (SHS) has not been determined to date. METHODS: Timed pregnant RAGE null and wild type control mice were exposed to 4 consecutive days of SHS from embryonic day (E) 14.5 through E18.5 using a state of the art nose-only smoke exposure system (Scireq, Montreal, Canada). RAGE expression was assessed using immunofluorescence, immunoblotting, and quantitative RT-PCR. TUNEL immunostaining and blotting for caspase-3 were performed to evaluate effects on cell turnover. Matrix abnormalities were discerned by quantifying collagen IV and MMP-9, a matrix metalloprotease capable of degrading basement membranes. Lastly, TNF-α and IL-1ß levels were assessed in order to determine inflammatory status in the developing lung. RESULTS: Pulmonary RAGE expression was elevated in both dams exposed to SHS and in fetuses gestating within mothers exposed to SHS. Fetal weight, a measure of organismal health, was decreased in SHS-exposed pups, but unchanged in SHS-exposed RAGE null mice. TUNEL assessments suggested a shift toward pulmonary cell apoptosis and matrix in SHS-exposed pups was diminished as revealed by decreased collagen IV and increased MMP-9 expression. Furthermore, SHS-exposed RAGE null mice expressed less TNF-α and IL-1ß when compared to SHS-exposed controls. CONCLUSIONS: RAGE augmentation in developing pups exposed to maternal SHS weakens matrix deposition and influences lung inflammation.