The synaptic ribbon is critical for sound encoding at high rates and with temporal precision.

We studied the role of the synaptic ribbon for sound encoding at the synapses between inner hair cells (IHCs) and spiral ganglion neurons (SGNs) in mice lacking RIBEYE (RBEKO/KO). Electron and immunofluorescence microscopy revealed a lack of synaptic ribbons and an assembly of several small active zones (AZs) at each synaptic contact. Spontaneous and sound-evoked firing rates of SGNs and their compound action potential were reduced, indicating impaired transmission at ribbonless IHC-SGN synapses. The temporal precision of sound encoding was impaired and the recovery of SGN-firing from adaptation indicated slowed synaptic vesicle (SV) replenishment. Activation of Ca2+-channels was shifted to more depolarized potentials and exocytosis was reduced for weak depolarizations. Presynaptic Ca2+-signals showed a broader spread, compatible with the altered Ca2+-channel clustering observed by super-resolution immunofluorescence microscopy. We postulate that RIBEYE disruption is partially compensated by multi-AZ organization. The remaining synaptic deficit indicates ribbon function in SV-replenishment and Ca2+-channel regulation

A rare case of amyopathic juvenile dermatomyositis associated with psoriasis successfully treated with ustekinumab

Coexistence between two or more immunological-mediated diseases implies a clinical and therapeutic challenge that is uncommon in the clinical field. We report a rare case of a young patient with amyopathic juvenile dermatomyositis and erythrodermic psoriasis, with an excellent response to ustekinumab

Endophilin-A regulates presynaptic Ca2+ influx and synaptic vesicle recycling in auditory hair cells

Ribbon synapses of cochlear inner hair cells (IHCs) operate with high rates of neurotransmission; yet, the molecular regulation of synaptic vesicle (SV) recycling at these synapses remains poorly understood. Here, we studied the role of endophilins-A1-3, endocytic adaptors with curvature-sensing and curvature-generating properties, in mouse IHCs. Single-cell RT-PCR indicated the expression of endophilins-A1-3 in IHCs, and immunoblotting confirmed the presence of endophilin-A1 and endophilin-A2 in the cochlea. Patch-clamp recordings from endophilin-A-deficient IHCs revealed a reduction of Ca2+ influx and exocytosis, which we attribute to a decreased abundance of presynaptic Ca2+ channels and impaired SV replenishment. Slow endocytic membrane retrieval, thought to reflect clathrin-mediated endocytosis, was impaired. Otoferlin, essential for IHC exocytosis, co-immunoprecipitated with purified endophilin-A1 protein, suggestive of a molecular interaction that might aid exocytosis-endocytosis coupling. Electron microscopy revealed lower SV numbers, but an increased occurrence of coated structures and endosome-like vacuoles at IHC active zones. In summary, endophilins regulate Ca2+ influx and promote SV recycling in IHCs, likely via coupling exocytosis to endocytosis, and contributing to membrane retrieval and SV reformation

Prevalence of multiple sclerosis in Bogotá, Colombia

Entre los países latinoamericanos, Colombia se considera un área de bajo riesgo de esclerosis múltiple (EM) y no se han realizado estudios sobre la prevalencia de la EM en ninguno de los grandes entornos urbanos del país. Para llenar este vacío y evaluar la prevalencia de EM en Bogotá al 31 de diciembre de 2002, este estudio revisó las historias clínicas de pacientes diagnosticados con EM en la mayoría de los hospitales de Bogotá. Esta revisión produjo una muestra de 296 pacientes con un diagnóstico de EM, cuya fiabilidad fue verificada por un neurólogo con experiencia en EM. La tasa de prevalencia total identificada para diciembre de 2002 fue de 4,41 / 100.000 habitantes (95% CI 3,9-4,9), incluida una tasa de 5,98 / 100.000 (95% CI 5,2-6,8) para las mujeres y 2,71 / 100.000 (95% CI 2,2-3,3) ) para los hombres (diferencias medidas en p <0,001). Las estimaciones de prevalencia para Bogotá confirman el estatus de la ciudad como un área de bajo riesgo para la EM.Among Latin American countries, Colombia is considered a low-risk area for multiple sclerosis (MS) and no studies on MS prevalence have been conducted in any of the country's large urban settings. To fill this gap and assess the prevalence of MS in Bogotá as of December 31, 2002, this study reviewed the clinical records of patients diagnosed with MS in most Bogotá hospitals. This review produced a sample of 296 patients with an MS diagnosis whose reliability was verified by a neurologist with expertise in MS. The total prevalence rate identified for December 2002 was 4.41/100,000 inhabitants (95% CI 3.9-4.9), including a rate of 5.98/100,000 (95% CI 5.2-6.8) for women and 2.71/100,000 (95% CI 2.2-3.3) for men (differences measured at p < 0.001). The prevalence estimates for Bogotá, confirm the city's status as a low-risk area for MS

Antioquia Médica, Vol. 1, No. 10. Julio

Memorándum de necesidades del hospital; Los prematuros; Enseñanza y formación profesional del personal médico y del personal auxiliar de salud pública; Síndrome de adaptación general y enfermedades de adaptación; Anotaciones sobre estreptomicina; Cirugía torácica Vs. Toracoplastia en tuberculosis pulmonar; Quinta Conferencia Nacional de Turberculosis; Cáncer cutáneo; Reacción de Bolen en el diagnóstico de malignidad; Sesión del 27 de junio; Boletín No. 6; Ciclo de conferencias sobre Anestesia en el parto; I Congreso Panamericano de Educación Médica de Lima (Perú); Facultad de Medicina de Cali; Literatura Médica Colombiana

Estudio de la ocupación del mecánico de continuas de hilar

Estudio sectorial de la ocupación de mecánico de continuas de hilar en el que se hace una descripción detallada de las tareas desarrolladas en trabajo y cómo realizarlas, estado del sector de hilandería en el país a 1966, análisis sectorial, personal del sector, maquinaria, herramientas y materiales, condiciones de trabajo y competencias necesarias para el cargo.Sectoral study of the occupation of spinning machine mechanics in which a detailed description of the tasks carried out on the job and how to carry them out, state of the spinning sector in the country as of 1966, sector analysis, sector personnel, machinery, tools and materials, working conditions and skills necessary for the position.Resumen de los análisis ocupacionales -- Trabajo realizado -- Condiciones del trabajo y riesgos profesionales -- Monografía profesional -- Exigencias del trabajo -- Características del trabajador (perfil) -- Datos complementarios -- Datos estadísticosna37 página