Soluble or soluble/membrane TNF-α inhibitors protect the brain from focal ischemic injury in rats.

Tumor Necrosis Factor-alpha (TNF-α) is an immunomodulatory and proinflammatory cytokine implicated in neuro-inflammation and neuronal damage in response to cerebral ischemia. The present study tested the hypothesis that anti-TNF-α agents may be protective against cerebral infarction. Transient focal ischemia was artificially induced in anesthetized adult male Wistar rats (300-350 g) by middle cerebral artery occlusion (MCAO) with an intraluminal suture. TNF-α function was interfered with either a chimeric monoclonal antibody against TNF-α (infliximab-7 mg/kg) aiming to TNF-α soluble and membrane-attached form; or a chimeric fusion protein of TNF-α receptor-2 with a fragment crystallizable (Fc) region of IgG1 (etanercept-5 mg/kg) aiming for the TNF-α soluble form. Both agents were administered intraperitoneally 0 or 6 h after inducing ischemia. Infarct volume was measured by 2,3,5-triphenyltetrazolium chloride staining. Cerebral infarct volume was significantly reduced in either etanercept or infliximab-treated group compared with non-treated MCAO rats 24 h after reperfusion. These results suggest that anti-TNF-α agents may reduce focal ischemic injury in rats.

Desarrollo y maduración normal de la médula ósea, valoración porresonancia magnética / Normal Development and Maturation of Bone Marrow Assessment by Magnetic Resonance Imaging

La maduración ósea ocurre de forma ordenada y predecible. Puede documentarse por medio de resonancia magnética incluso antes de que ocurran cambios histológicos, por lo cual es importante su adecuado conocimiento y caracterización.

Skeletal maturation occurs in an orderly and predictable manner. It can be documented by Magnetic Resonance Imaging even before histological changes occurs, so the importance of adequate knowledge and characterization must be stated.

Characterization and distribution of tomato yellow margin leaf curl virus, a begomovirus from Venezuela.

A begomovirus causing mottling and leaf deformation in tomato from the State of Mérida was cloned and sequenced. The virus has a bipartite genome comprised of a DNA-A (2,572 nucleotides) and a DNA-B (2,543 nucleotides) with a genome organization typical of New World begomoviruses. Both components share a common region of 115 nucleotides with 98 % sequence identity. Phylogenetic analysis indicated that while no virus sequences were closely related, the A component was distantly related to those of two other tomato-infecting viruses, tomato leaf deformation virus and Merremia mosaic virus; and the DNA-B, to those of pepper huasteco yellow vein virus and Rhynchosia golden mosaic Yucatan virus. The DNA-A and DNA-B sequences were submitted to GenBank (accession no. AY508993 and AY508994, respectively) and later accepted by the International Committee on Taxonomy of Viruses as the genome of a member of a unique virus species with the name Tomato yellow margin leaf curl virus (TYMLCV). Tomato (Solanum lycopersicum L. 'Fl. Lanai') plants inoculated with cloned TYMLCV DNA-A and DNA-B became systemically infected and showed chlorotic margins and leaf curling. The distribution of TYMLCV in tomato-producing states in Venezuela was determined by nucleic acid spot hybridization analysis of 334 tomato leaf samples collected from ten states using a TYMLCV-specific probe and confirmed by PCR and sequencing of the PCR fragment. TYMLCV was detected in samples from the states of Aragua, Guárico, and Mérida, suggesting that TYMLCV is widely distributed in Venezuela.

Clinical features of multiple sclerosis in a genetically homogeneous tropical population.

Individuals affected with multiple sclerosis (MS) from a genetically homogeneous Caucasian population in Antioquia, a tropical region of Colombia, were evaluated in order to observe the clinical behavior of the disease. The frequency of clinical manifestations in 65 patients with definite MS from Antioquia was compared with those reported from temperate regions. The most common manifestations were optic neuritis and motor symptoms with absence of cerebellar symptoms. This presentation is significantly different from the frequency distribution at onset in series from temperate regions. These differences suggest that environmental factors could modify the clinical expression of MS in this population.

[Multiple sclerosis: epidemiological-genetic studies in the population of Antioquia, Colombia. Disequilibrium of HLA DQ alpha]. / Esclerosis múltiple: aproximación epidemiológico-genética en habitantes de Antioquia, Colombia. Desequilibrio de ligamiento al HLA DQ alpha.

INTRODUCTION AND OBJECTIVE: Discrimination and quantification of the environmental and genetic components involved in developing multiple sclerosis (MS) have not been made. In order to discriminate these components we have ascertained affected individuals by MS belonging to the Paisa community from Antioquia, Colombia, a state localized in the tropical area of South America, to detect eventual linkage disequilibrium to HLA, locus DQ alpha, which could demonstrate the relevance of the genetic component. DEVELOPMENT: A contingence analysis among case-control HLA DQ alpha genotype distributions, by using Monte Carlo resampling method to solve small number sample, showed that there are significant differences between the two groups. We observe that HLA DQ alpha 1.1, 1.2 allele frequencies were higher in the cases than in the controls. Also, there was significant HLA DQ alpha 3 allele lower frequency (p < 0.05) in the cases than in the controls. CONCLUSIONS: Similar results have been described in other Caucasian populations living in non tropical areas. Before results could indicate that the Caucasoid populations genetic component implied in the susceptibility to MS have remained in Paisa community, whether the environmental component, being meaningful to develop MS.

Multiple sclerosis: association to HLA DQalpha in a tropical population.

Studies performed in subtropical populations have found significant association between the phenotype multiple sclerosis (MS) and the major histocompatibility complex (MHC). We present the results of a case-control study conducted on a tropical population (Antioquia, Colombia) in order to detect a possible association between MS and HLA DQalpha (HLA DQA1*) alleles. Forty chromosomes belonging to MS patients were compared to two sets of controls (40 and 910 chromosomes, respectively). The HLA DQA1*0101 and DQA1*0102 alleles were found in a significantly higher proportion among the cases than among the controls, whereas the HLA DQA1*0103 allele was found in a significantly lower proportion of the cases. These results suggest that the association of HLA DQA1*0101, DQA1*0102 and DQA1*0103 to the MS phenotype found in Caucasian subtropical populations remains in individuals with MS inhabiting the tropics. This finding could mean that the major genetic component associated to the MHC in subtropical populations is the same in the tropics.

Esclerosis múltiple: aproximación epidemiológico-genética en habitantes de Antioquia, Colombia. II: desequilibrio de ligamento al HLA DQÓ / Multiple sclerosis: an epidemiologycal approach in Antioquia, Colombia. II: Linkage desequilibrium to HLA, locus DQÓ

La discriminación y cuantificación de los componentes ambientales y genéticos en el desarrollo de esclerosis múltiple (EM) no se ha podido realizar. con la finalidad de acercarnos a la discriminación de dichos componentes, hemos analizado casos afectados de EM a partir de la comunidad paisa de Antioquia, Colombia, zona situada en el trópico; para detectar un posible desequilibrio de ligamiento al HLA, locus DQÓ, aspecto que revelaría la importancia del componente genético en el desarrollo de EM. Un análisis de contingencia entre las distribuciones genotípicas del HLA DQÓ de los casos y controles, usando el remuestreo de Monte Carlo para solucionar el problema del tamaño muestral que es inherente a las poblaciones con baja prevalencia de EM, reveló que existen diferencias significativas entre las dos distribuciones. La tendencia alélica observada fue de un incremento de los alelos 1.1., 1.2 y una disminución de los alelos 3 (con un p significativamente < de 0,05) y 4 en la población afectada. Los mismos resultados han sido descritos en otras poblaciones de origen caucasoide no localizadas en el trópico, lo cual puede indicar que este componente genético descrito en la población caucasoide se ha mantenido en la poblaciòn de enfermos con EM originarios de Antioquia y que continúa siendo importante para el desarrollo de la enfermedad

[Prevalence of neurocysticercosis in individuals affected by epilepsy]. / Prevalencia de neurocisticercosis en individuos afectados de epilepsia.

INTRODUCTION: In this investigations, was carried out a neurocysticercosis (NC) prevalence study during seven months in the Instituto Neurológico de Antioquia with the purpose of known neurocysticercosis frequency as cause of epilepsy in patients older than ten years that we attended in our institute. MATERIAL AND METHODS: Computerized tomographies (CT) were made to 503 patients, with epilepsy, 24.7% of them were CT positive for NC. Cysticercosis enzyme linked immunoelectrotransfer blot (EITB) and enzyme linked immunoabsorbent assay (ELISA) test were made to 178 patients, 19.6% were EITB positive for NC and 5% ELISA positive for NC. Results. From this result it is possible to infer that about 8% of the 503 patients with epilepsy had cysticercosis, according to EITB that is the golden assay for NC. The CT and ELISA test had 94.3% and 27.7% sensitivity, respectively, according to EITB. The specificity of the CT for NC was 49.2% and specificity for ELISA test was 100% as compared to EITB. The multivariate analysis with logistic regression allowed to establish association of positive EITB with factors such as male sex, eating pork, headaches and multiple lesions in CT. CONCLUSIONS: Prevention and education actions are necessary for the interruption of the neurocysticercosis transmission chain in order to diminish the high prevalence of epilepsy in the country and its complication and consequences.

Sindrome hipereosinofilico idiopatico de 27 anos de evolucion / Idiopatic hypereosinophilic syndrome of 27 years of evolution

Se presenta el caso de una paciente de 53 anos con un sindrome hipereosinofilico de 27 anos de evolucion, con manifestaciones basicamente del sistema digestivo, como oclusion y pseudooclusion intestinales y ascitis. En los primeros anos fue sometida a varias intervenciones quirurgicas y se le prescribrieron esteroides, obteniendose buena respuesta. Este caso contrasta, por su larga evolucion, con lo descrito hasta ahora en la literatura.