Abstract The state of Zulia concentrates 61.18% of the aboriginal population of Venezuela, of wich the Añú are the second largest group, after the Wayúu. 29 Añú individuals were studied, and DNA extraction was performed by means of a method that combines two techniques (Fenol / Sevag and Salting-Out), proceeding to their amplification through multiplex PCR, using the Promega Powerplex®16HS Kit, determining the allele frequencies of 15 autosomal STR markers: D3S1358, TH01, D21S11, D18S51, PENTA E, D5S818, D13S317, D7S820, D16S539, CSF1P0, PENTA D, vWA, D8S1179, TPOX, FGA and AMELOGENINE. Genotyping was performed after the comparison of STR fragments with the allelic ladder and the standard internal lane size using the GeneMapper® ID-X software, Version 1.2, with the highest allelic frequencies for each genetic marker being the following: the allele 18 of the locus D3S1358 (0.448), allele 6 of TH01 (0.586), allele 30 D21S11 (0.379), allele 12 D18S51 (0.275), allele 14 Penta E (0.258), allele 11 D5S818 (0.603), allele 12 D13S317 (0.327) , allele 11 D7S820 (0.586), allele 12 D16S539 (0.310), allele 10 CSF1PO (0.344), allele 11 Penta D (0.327), allele 16 vWA (0.620), allele 14 D8S1179 (0.431), allele 8 TPOX (0.551) and allele 24 FGA (0.396). According to Nei’s matrix of distance, the Añú population does not share its genetic stock with other Zulian indigenous groups or the American continent, indicating that this ethnic group has its own ancestral origin with little or no external genetic contribution.

Resumen En el estado Zulia se encuentra 61.18% de la población aborigen de Venezuela. La etnia añú es el segundo grupo de indígenas más numeroso, después de los wayúu. Se estudiaron 29 individuos añú, a los cuales se les realizó extracción de ADN por medio de un método que combina dos técnicas (Fenol/Sevag y Salting-Out), se procedió a la amplificación de las mismas a través de la PCR multiplex, se empleó el Kit Promega Powerplex®16HS, y se determinó las frecuencias alélicas de 15 marcadores STR´s autosómicos: D3S1358, TH01, D21S11, D18S51, PENTA E, D5S818, D13S317, D7S820, D16S539, CSF1P0, PENTA D, vWA, D8S1179, TPOX, FGA y AMELOGENINA. La genotipificación se realizó después de la comparación de fragmentos de STR con la escalera alélica y el tamaño del carril interno estándar utilizando el software GeneMapper® ID-X, Versión 1.2; las mayores frecuencias alélicas para cada marcador genético fueron las siguientes: el alelo 18 del locus D3S1358 (0.448), alelo 6 de TH01 (0.586), alelo 30 D21S11 (0.379), alelo 12 D18S51 (0.275), alelo 14 Penta E (0.258), alelo 11 D5S818 (0.603), alelo 12 D13S317 (0.327), alelo 11 D7S820 (0.586), alelo 12 D16S539 (0.310), alelo 10 CSF1PO (0.344), alelo 11 Penta D (0.327), alelo 16 vWA (0.620), alelo 14 D8S1179 (0.431), alelo 8 TPOX (0.551) y alelo 24 FGA (0.396). Según la matríz de distancia de Nei, la población añú no comparte su Acervo Genético con otros grupos indígenas zulianos ni del continente americano, lo cual indica que este grupo étnico tiene su propio origen ancestral con poco o ningún aporte genético externo.

There is increasing investigation and scientific publications related to stem cells. In our literature review, we describe what a stem cell is, what are it’s properties, some of the strategies to isolate and proliferate neural stem cells and the molecular mechanisms involved in the functional integration of these cells in the receptor cells. Finally, the possible steps in future investigations are described: better identification of the signals from the receptor to the donor cells; how to decipher in more depth the neurogenic capacity at a cellular level in the adult brain

Las investigaciones sobre células troncales han concitado creciente actividad en el campo de la investigación y publicaciones científicas. Nuestra revisión de la literatura expone qué es una célula troncal, sus propiedades, algunas de las estrategias para aislar y hacer proliferar células troncales neurales y los mecanismos moleculares involucrados en la integración funcional de estas células al cerebro receptor. Finalmente se comentan los posibles pasos de las futuras investigaciones, las que deberán identificar mejor las señales del receptor a las células donantes, así como descifrar con mayor profundidad la capacidad neurogénica del ambiente celular del cerebro adulto

Listeria monocytogenes infections can involve the central nervous system in the form of a rhomboencephalitis. Three possible cases of rhomboencephalitis by Listeria monocytogenes are reported (2 females, aged 44 and 49 and a man of 36 years old). The three cases were preceded by an unspecific prodrome of headache, vertigo and fever in absence of a meningeal syndrome. The neurological stage was defined by the unilateral involvement of cranial nerves and the cerebellum and a clear inflammatory cerebrospinal fluid (CSF) with the presence of polymorphonuclear leukocytes, and normal glucose and protein levels. A magnetic nuclear resonance (MRI) showed the appearance of characteristic images, present in the bulboprotuberancial region. These images are one of the most constant features of this disease, reported in the literature. The early diagnosis of rhomboencephalitis was based on the clinical picture, the study of the CSF and the MRI, allowing the use of antimicrobials, prior to microbiological identification. Therefore, the risk of brain stem and cardiac complications of the disease is reduced (Rev Méd Chile 2003; 131: 921-8)

We report a previously healthy 44 years old female, that presented with mild clouding of consciousness, a left cerebellar syndrome, involvement of V, X and XII left cranial nerves and an alteration of epicritic sensitivity in the left half of the body. Cerebrospinal fluid had inflammatory features. Cerebrospinal fluid and blood cultures were positive for Listeria monocytogenes. Magnetic resonance imaging disclosed a rhomboencephalitis. Antibiotics were started and the clinical condition of the patient improved progressively. After three months of follow up, the patient is notably recovered and there is a regression of hyperintense lesions of the brainstem in the magnetic resonance imaging. The diagnosis of Listeria monocytogenes infection must be born in mind in the presence of a rhomboencephalitis.

Two syndromatic forms of Creutzfeldt-Jakob disease are illustrated with data from two cases confirmed by necropsy and studied by means of electroencephalogram, evoked potential recording and neuropathological techniques. One of the cases presented the typical hypersynchronous periodic discharges thougth to be characteristic of this disease. The other did not exhibit epileptiform diischarges, showing an evolution in which progressive diffuse slowing was the prominent feature. Cortical spongyosis, gliosis, and neuronal lose were intense in the case showing spikes, and moderate in the one without spikes. Subcortical involvement was similar in both cases. This different topography of pathological involvement might explain, in addition to electroencephalographic findings, the different behavior of somatosensory evoked potentials, which were of larger amplitude in the case showing epileptiform discharges, although in both cases deterioration of clinical state was accompanied by a progressive amplitude decrement in the evoked potential. Sleep induced by barbiturates was disrupted in the case with spikes, its pattern being closer to normal in the case with less severe cortical involvement. A Wada test demostrated that discharges in the hemispheres were independent. Spike periodicity is discussed. It is postulated that the heavier involvement of cortical layers II to IV deprive the remaining pyramidal cells of inhibitory influences, a condition which might explain the generation of periodic spike discharges.

Se estudian dos casos de enfermedad de Creutzfeldt-Jakob comprobados por examen necrópsico. Uno de ellos presentaba típicas descargas hipersincrónicas, periódicas en el electroencefalograma; el otro caso no mostraba estas descargas epileptiformes y evolucionó con una lentitud difusa progresiva. La espongiosis, gliosis y pérdida neuronal fué intensa en la corteza del caso con espigas y muy moderada en el caso sin espigas. El compromiso subcortical era similar en ambos casos. Se postula que la diferente expresión topográfica de su histopatología explicaria tambien la diferencia en el comportamiento de los potenciales evocados somatosensoriales y el diferente modelo electroencefalográfico del sueno penthotálico. La independencia de las descargas epileptiformes en cada hemisferio se prueba con el test de Wada. Se discute el origen de las espigas y su periodicidad. Se postula teóricamente que el predominio de las lesiones de las capas II a IV privaria a las células piramidales remanentes, de influencias inhibitorias, lo que explicaria la génesis de las espigas.