Arginase-1 is expressed exclusively by infiltrating myeloid cells in CNS injury and disease.

Resident microglia and infiltrating myeloid cells play important roles in the onset, propagation, and resolution of inflammation in central nervous system (CNS) injury and disease. Identifying cell type-specific mechanisms will help to appropriately target interventions for tissue repair. Arginase-1 (Arg-1) is a well characterised modulator of tissue repair and its expression correlates with recovery after CNS injury. Here we assessed the cellular localisation of Arg-1 in two models of CNS damage. Using microglia specific antibodies, P2ry12 and Fc receptor-like S (FCRLS), we show the LysM-EGFP reporter mouse is an excellent model to distinguish infiltrating myeloid cells from resident microglia. We show that Arg-1 is expressed exclusively in infiltrating myeloid cells but not microglia in models of spinal cord injury (SCI) and experimental autoimmune encephalomyelitis (EAE). Our in vitro studies suggest that factors in the CNS environment prevent expression of Arg-1 in microglia in vivo. This work suggests different functional roles for these cells in CNS injury and repair and shows that such repair pathways can be switched on in infiltrating myeloid cells in pro-inflammatory environments.

[Correlation between socioeconomic factors and in-hospital mortality from ischemic stroke in a hospital cohort in Colombia, 2003-2006]. / Asociación entre factores socioeconómicos y mortalidad intrahospitalaria por accidente cerebrovascular isquémico en una cohorte hospitalaria de Colombia, 2003-2006.

OBJECTIVE: To determine if there is a correlation between socioeconomic conditions and in-hospital mortality (IHM) from ischemic stroke in a sample of the Colombian population and identify the chain of events that determine that association. METHODS: Prospective study of a hospital cohort of patients with ischemic stroke in four Colombian clinical referral institutions-located in Floridablanca, Bucaramanga, Bogotá, and Medellín-between February 2003 and December 2006. Hierarchical analysis was used to group the socioeconomic variables into three levels, and their relationship to IHM due to ischemic stroke was assessed in a Cox proportional hazards model. RESULTS: The IHM rate was 9.4% in the 253 patients included in the study. In the analysis by levels, mortality was inversely associated with educational level (advanced to primary), monthly income (≥ minimum wage), and participation in the contributory health system. When the three levels were combined in the hierarchical analysis, affiliation with the contributory system was the only association that maintained its statistical significance (RR 0.35; CI 95%: 0.13-0.96; P = 0.04). CONCLUSIONS: The results indicate that, in Colombia, being affiliated with the contributory health system is an independent protective factor against IHM after an ischemic stroke. The education-income-access to health services sequence is a possible explanation for the relationship between socioeconomic conditions and the clinical outcome of these events. Strategies should be designed to mitigate the differences in the quality and distribution of health services in the Colombian population.

Asociación entre factores socioeconómicos y mortalidad intrahospitalaria por accidente cerebrovascular isquémico en una cohorte hospitalaria de Colombia, 2003-2006 / Correlation between socioeconomic factors and in-hospital mortality from ischemic stroke in a hospital cohort in Colombia, 2003-2006

OBJETIVO: Determinar si existe asociación entre las condiciones socioeconómicas y la mortalidad intrahospitalaria (MIH) por accidente cerebrovascular (ACV) isquémico en una muestra de población colombiana e identificar la cadena de eventos que determinan esa asociación. MÉTODOS: Estudio prospectivo de una cohorte hospitalaria de pacientes con ACV isquémico registrados en cuatro instituciones clínicas de referencia colombianas -ubicadas en Floridablanca, Bucaramanga, Bogotá y Medellín- entre febrero de 2003 y diciembre de 2006. Mediante análisis jerárquico se evaluaron las variables socioeconómicas agrupadas en tres niveles para determinar su relación con la MIH por ACV isquémico en un modelo de riesgos proporcionales de Cox. RESULTADOS: En los 253 pacientes incluidos, la MIH fue de 9,4 %. En el análisis por niveles, la mortalidad estuvo inversamente asociada con el nivel educacional (estudios superiores a primaria), los ingresos mensuales (≥ salario mínimo) y la vinculación al régimen contributivo. En el análisis jerárquico, al combinar los 3 niveles, solo la asociación inversa con la afiliación al régimen contributivo mantuvo su significación estadística (RR 0,35; IC95%: 0,13-0,96; P = 0,04). CONCLUSIONES: Los resultados indican que en Colombia, el estar afilado al régimen contributivo de salud es un factor protector independiente contra la MIH tras un ACV isquémico. La secuencia educación-ingresos-acceso a servicios de salud constituye una vía de explicación de la relación entre las condiciones socioeconómicas y el desenlace clínico de estos eventos. Se deben diseñar estrategias para mitigar las diferencias en la calidad y la distribución de los servicios de salud en la población colombiana.

OBJECTIVE: To determine if there is a correlation between socioeconomic conditions and in-hospital mortality (IHM) from ischemic stroke in a sample of the Colombian population and identify the chain of events that determine that association. METHODS: Prospective study of a hospital cohort of patients with ischemic stroke in four Colombian clinical referral institutions-located in Floridablanca, Bucaramanga, Bogotá, and Medellín-between February 2003 and December 2006. Hierarchical analysis was used to group the socioeconomic variables into three levels, and their relationship to IHM due to ischemic stroke was assessed in a Cox proportional hazards model. RESULTS: The IHM rate was 9.4% in the 253 patients included in the study. In the analysis by levels, mortality was inversely associated with educational level (advanced to primary), monthly income (≥ minimum wage), and participation in the contributory health system. When the three levels were combined in the hierarchical analysis, affiliation with the contributory system was the only association that maintained its statistical significance (RR 0.35; CI 95%: 0.13-0.96; P = 0.04). CONCLUSIONS: The results indicate that, in Colombia, being affiliated with the contributory health system is an independent protective factor against IHM after an ischemic stroke. The education-income-access to health services sequence is a possible explanation for the relationship between socioeconomic conditions and the clinical outcome of these events. Strategies should be designed to mitigate the differences in the quality and distribution of health services in the Colombian population.

Inflammatory pathways in spinal cord injury.

Injury to the spinal cord results in direct damage to axons, neuronal cell bodies, and glia that cause functional loss below the site of injury. In addition, the injury also triggers an inflammatory response that contributes to secondary tissue damage that leads to further functional loss. Reducing inflammation after spinal cord injury (SCI) is therefore a worthy therapeutic goal. Inflammation in the injured spinal cord is a complex response that involves resident cells of the central nervous system as well as infiltrating immune cells, and is mediated by a variety of molecular pathways and signaling molecules. Here, we discuss approaches we have used to identify novel therapeutic targets to modulate the inflammatory response after SCI to reduce tissue damage and promote recovery. Effective treatments for SCI will likely require a combination of approaches to reduce inflammation and secondary damage with those that promote axon regeneration.

Cefaleas secundarias a alteraciones vasculares cerebrales / Headache secondary to cerebrovascular disorders

Las cefaleas vasculares secundarias conforman el grupo 6 de la clasificación de la Sociedad Internacional de Cefaleas, las más importantes son la hemorragia subaracnoidea, el infarto cerebral, la trombosis venosa cerebral, la hemorragia intracerebral y el síndrome de Sturge-Weber. La cefalea puede ser el primer síntoma de una alteración vascular cerebral, por lo cual es importante considerar siempre esa posibilidad cuando llega un paciente con cefalea intensa, para establecer un diagnóstico y un tratamiento oportuno, que puede salvar la vida de los pacientes. Las neuroimágenes son una herramienta de gran ayuda para el diagnóstico de estas enfermedades. En este artículo se describen las manifestaciones clínicas, la fisiopatología, los métodos de diagnóstico y el tratamiento de estas alteraciones.

In the classification of the International Society of Headaches, secondary headaches atributed to vascular disorders are included in the Group 6, the most important are subarachnoid hemorrhage, cerebral infarction, venous cerebral thrombosis, intracerebral hemorrhage and the Sturge-Weber syndrome. The headache can be the first symptom of a cerebral vascular alteration, and for this reason it is important to consider always this possibility in patients with severe pain, to establish an opportune diagnosis and treatment which can save the live of the patient. Neuroimages are helpful tools for the diagnosis of these disorders. In the present review are described the clinical manifestations, pathophysiology, diagnoses and treatment of these alterations.