Resolución de operaciones de suma y resta en adolescentes sordos

Considerando el retraso escolar en el área de matemáticas en la población sorda, la investigación presentada estudia el desarrollo de estrategias de resolución de operaciones de adición y sustracción en siete adolescentes sordos profundos prelocutivos de edades entre 12:04 y 15:11, en situación de interacción entre iguales, y pretende elaborar algunas recomendaciones didácticas a fin de mejorar el rendimiento matemático de esta población. Las estrategias de resolución halladas se adecuan a las categorías previamente formuladas para niños oyentes. Algunos de los tipos de errores detectados presentan características específicas, diferentes de las previamente descritas en la literaturaConsidering deaf children's tendency to fall behind in mathematics, the research we present aims to study the addition and subtraction solving strategies development of seven deaf from birth adolescents (aged 12:04 and 15:11) in a peer interaction situation and to offer some educational suggestions to enhance their performance in mathematics. The students' strategies fit into previously formulated classical categories of solving strategies for hearing children. However, some of the types of errors found show specific features, different from the ones previously referred to in the literatur

Familial amyloid polyneuropathy associated with TTRSer50Arg mutation in two Iberian families presenting a novel single base change in the mutant gene

Amyloid. 2007 Jun;14(2):147-52. Familial amyloid polyneuropathy associated with TTRSer50Arg mutation in two Iberian families presenting a novel single base change in the mutant gene. Munar-Qués M, Masjuan J, Coelho T, Moreira P, Viader-Farré C, Saraiva MJ. Grupo de Estudio de la PAF, Plaza Olivar 5, 07002 Palma de Mallorca, Majorca, Spain. [email protected] Abstract We present two families, from Spain and Portugal, with familial amyloid polyneuropathy (FAP) associated with the mutation TTRSer50Arg. This mutation was first described in two Japanese patients from independent families and later in a French-Italian patient and a Vietnamese family. The two families presented here, are the first to be diagnosed with this mutation in the Iberian Peninsula. In the patients of both families, FAP was very aggressive as they rapidly developed multiple symptoms with progressive deterioration; we emphasize the presence of severe orthostatic hypotension in the Spanish proband which confined him to a wheelchair. This proband was the first patient with this mutation to have undergone liver transplantation and results were encouraging. The mutation was detected in four patients and one disease-free relative by DNA sequencing of exon 3 and induced mutation restriction analysis. The most outstanding feature was the single base transversion A to C in codon 50 (CGT instead of AGT), whereas in both Japanese patients and the French-Italian patient it was T to G (AGG instead of AGT). To our knowledge only six FAP mutations with more than one single nucleotide mutation for the same codon have been reported to date. PMID: 17577688 [PubMed - indexed for MEDLINE

La integración sociocultural de la Comunidad Sorda en Cataluña : implicaciones en las prácticas educativas

Este texto se presentó como comunicación al II Congreso Internacional de Etnografía y Educación: Migraciones y Ciudadanías. Universidad Autónoma de Barcelona, Barcelona, 5-8 Septiembre 2008.El objetivo principal de este trabajo es analizar el estado de la cuestión actual de la integración sociocultural de la Comunidad Sorda y sus implicaciones en las prácticas educativas que se llevan a cabo en los centros escolares. Amenudo la sordera se ha considerado un fenómeno homogéneo y en consecuencia, las personas sordas son vistas como un colectivo unificado que comparte un mismo problema. Sin embargo, en realidad se trata de un colectivo extremadamente heterogéneo, cuyas características dependen factores muy diversos. Destacamos dos grandes perspectivas desde las cuales, a lo largo de la historia, se ha contemplado a este colectivo. Podemos hablar de un modelo clínico patológico de la sordera versus un modelo sociocultural. El primero sustentado en una perspectiva centrada fundamentalmente en el déficit y aquello que la persona sorda no puede hacer, en comparación con lo que se ha dado en denominar la ¨norma¨. Define la sordera como un estado patológico. Por otro lado, una perspectiva basada en la consideración de la forma de percibir el mundo por un canal prioritariamente viso-gestual como un identificador cultural. Ambos modelos han condicionado la forma en que recientemente se ha llevado a cabo la investigación sobre la sordera y han influido en la visión social sobre las personas sordas y su educación. Desde la perspectiva clínica es habitual trabajar con una clasificación de la sordera que diferencia las patologías atribuibles a un trastorno del oído; le interesa más el origen, el grado y tipo de pérdida, su aparición y la patología estructural de la sordera, que las implicaciones que pueda tener para el individuo (fundamentalmente: dependencia, rechazo de un comportamiento auditivo anormal, baja autoestima y ruptura de las relaciones sociales, entre otros). Sin embargo, un número cada vez mayor de personas sordas reclaman que se las vea y respete como un grupo cultural distinto con sus propias creencias, necesidades, opiniones, costumbres y lengua, en definitiva, como una minoría cultural. Los miembros de la Comunidad Sorda definen la sordera como un término cultural y lo distinguen utilizando letras mayúsculas. Ambas perspectivas se contraponen porque se sustentan en nociones diferentes de la sordera. Esto se refleja también en la respuesta educativa actual en algunos colegios de niños sordos donde la defensa del uso de la lengua de signos como parte del currículum escolar entra en conflicto con el anclaje de algunos profesores en una todavía exclusiva formación monolingüe en una lengua hablada, como única forma legítima de comunicar con los sordos

Schwann cell mitochondrial metabolism supports long-term axonal survival and peripheral nerve function

Mitochondrial dysfunction is a common cause of peripheral neuropathies. While the role of neuron and axonal mitochondria in peripheral nerve disease is well appreciated, whether Schwann cell (SC) mitochondrial deficits contribute to peripheral neuropathies is unclear. Here we examine how SC mitochondrial dysfunction affects axonal survival and contributes to the decline of peripheral nerve function by generating mice with SC-specific mitochondrial deficits. These mice (Tfam-SCKOs) were produced through the tissue-specific deletion of the mitochondrial transcription factor A gene (Tfam), which is essential for mitochondrial DNA (mtDNA) transcription and maintenance. Tfam-SCKOs were viable but, as they aged, they developed a progressive peripheral neuropathy characterized by nerve conduction abnormalities as well as extensive muscle denervation. Morphological examination of Tfam-SCKO nerves revealed early preferential loss of small unmyelinated fibers followed by prominent demyelination and degeneration of larger-caliber axons. Tfam-SCKOs displayed sensory and motor deficits consistent with this pathology. Remarkably, the severe mtDNA depletion and respiratory chain abnormalities in Tfam-SCKO mice did not affect SC proliferation or survival. Mitochondrial function in SCs is therefore essential for maintenance of axonal survival and normal peripheral nerve function, suggesting that SC mitochondrial dysfunction contributes to human peripheral neuropathies

Differential Regional and Subtype-Specific Vulnerability of Enteric Neurons to Mitochondrial Dysfunction

Mitochondrial dysfunction is a central mediator of disease progression in diverse neurodegenerative diseases that often present with prominent gastrointestinal abnormalities. Gastrointestinal dysfunction in these disorders is related, at least in part, to defects in the enteric nervous system (ENS). The role of mitochondrial deficits in ENS neurodegeneration and their relative contribution to gastrointestinal dysfunction, however, are unclear. To better understand how mitochondrial abnormalities in the ENS influence enteric neurodegeneration and affect intestinal function, we generated mice (Tfam-ENSKOs) with impaired mitochondrial metabolism in enteric neurons and glia through the targeted deletion of the mitochondrial transcription factor A gene (Tfam). Tfam-ENSKO mice were initially viable but, at an early age, they developed severe gastrointestinal motility problems characterized by intestinal pseudo-obstruction resulting in premature death. This gastrointestinal dysfunction was caused by extensive, progressive neurodegeneration of the ENS involving both neurons and glia. Interestingly, mitochondrial defects differentially affected specific subpopulations of enteric neurons and regions of the gastrointestinal tract. Mitochondrial deficiency-related neuronal and glial loss was most prominent in the proximal small intestine, but the first affected neurons, nitrergic inhibitory neurons, had the greatest losses in the distal small intestine. This regional and subtype-specific variability in susceptibility to mitochondrial defects resulted in an imbalance of inhibitory and excitatory neurons that likely accounts for the observed phenotype in Tfam-ENSKO mice. Mitochondrial dysfunction, therefore, is likely to be an important driving force of neurodegeneration in the ENS and contribute to gastrointestinal symptoms in people with neurodegenerative disorders

El test de transformación de los linfocitos (TTL): Algunas aplicaciones del mismo en el laboratorio de análisis biológicos

Se estudió el test de transformación de linfocitos (TTL) analizándose algunos de los resultados obtenidos en sujetos no alérgicos y enfermos sensibilizados a diferentes sustancias: alergias alimenticias, alergias inhalantes, sustancias nitrogenadas específicas, sensibilizaciones medicamentosas y frente a células tumorales irradiadas empleando poblaciones linfoides autólogas. Se realizan finalmente unas consideraciones generales a las técnicas.The test transformation lymphocite (TTL) was studied, and the results obtained were analyzed in subjects with different substances (foods specific mitogens, inhalants alergens, drugs) and against irradiated tumor cells using autologous linfoide population. Finally general considerations to the technique were made

Impaired decision-making and brain shrinkage in alcoholism

Alcohol-dependent individuals usually favor instant gratification of alcohol use and ignore its long-term negative consequences, reflecting impaired decision-making. According to the somatic marker hypothesis, decision-making abilities are subtended by an extended brain network. As chronic alcohol consumption is known to be associated with brain shrinkage in this network, the present study investigated relationships between brain shrinkage and decision-making impairments in alcohol-dependent individuals early in abstinence using voxel-based morphometry. Thirty patients performed the Iowa Gambling Task and underwent a magnetic resonance imaging investigation (1.5T). Decision-making performances and brain data were compared with those of age-matched healthy controls. In the alcoholic group, a multiple regression analysis was conducted with two predictors (gray matter [GM] volume and decision-making measure) and two covariates (number of withdrawals and duration of alcoholism). Compared with controls, alcoholics had impaired decision-making and widespread reduced gray matter volume, especially in regions involved in decision-making. The regression analysis revealed links between high GM volume in the ventromedial prefrontal cortex, dorsal anterior cingulate cortex and right hippocampal formation, and high decision-making scores (P<0.001, uncorrected). Decision-making deficits in alcoholism may result from impairment of both emotional and cognitive networks

Silent cerebral infarct after cardiac catheterization as detected by diffusion weighted Magnetic Resonance Imaging: a randomized comparison of radial and femoral arterial approaches

Background and objective: Cerebral microembolism detected by transcranial Doppler (TCD) occurs systematically during cardiac catheterization, but its clinical relevance, remains unknown. Studies suggest that asymptomatic embolic cerebral infarction detectable by diffusion-weighted (DW) MRI might exist after percutaneous cardiac interventions with a frequency as high as 15 to 22% of cases. We have set up, for the first time, a prospective multicenter trial to assess the rate of silent cerebral infarction after cardiac catheterization and to compare the impact of the arterial access site, comparing radial and femoral access, on this phenomenon. Study design: This prospective study will be performed in patients with severe aortic valve stenosis. To assess the occurrence of cerebral infarction, all patients will undergo cerebral DW-MRI and neurological assessment within 24 hours before, and 48 hours after cardiac catheterization and retrograde catheterization of the aortic valve. Randomization for the access site will be performed before coronary angiography. A subgroup will be monitored by transcranial power M-mode Doppler during cardiac catheterization to observe cerebral blood flow and track emboli. Neuropsychological tests will also be recorded in a subgroup of patients before and after the interventional procedures to assess the impact of silent brain injury on potential cognitive decline. The primary end-point of the study is a direct comparison of ischemic cerebral lesions as detected by serial cerebral DW-MRI between patients explored by radial access and patients explored by femoral access. Secondary end-points include comparison of neuropsychological test performance and number of microembolism signals observed in the two groups. Implications: Using serial DW-MRI, silent cerebral infarction rate will be defined and the potential influence of vascular access site will be evaluated. Silent cerebral infarction might be a major concern during cardiac catheterization and its potential relationship to cognitive decline needs to be assessed. Study registration: The SCIPION study is registered through National Institutes of Health-sponsored clinical trials registry and has been assigned the Identifier: NCT 00329979

Risk of intracranial haemorrhage and ischaemic stroke after convexity subarachnoid haemorrhage in cerebral amyloid angiopathy: international individual patient data pooled analysis

OBJECTIVE: To investigate the frequency, time-course and predictors of intracerebral haemorrhage (ICH), recurrent convexity subarachnoid haemorrhage (cSAH), and ischemic stroke after cSAH associated with cerebral amyloid angiopathy (CAA). METHODS: We performed a systematic review and international individual patient-data pooled analysis in patients with cSAH associated with probable or possible CAA diagnosed on baseline MRI using the modified Boston criteria. We used Cox proportional hazards models with a frailty term to account for between-cohort differences. RESULTS: We included 190 patients (mean age 74.5 years; 45.3% female) from 13 centers with 385 patient-years of follow-up (median 1.4 years). The risks of each outcome (per patient-year) were: ICH 13.2% (95% CI 9.9-17.4); recurrent cSAH 11.1% (95% CI 7.9-15.2); combined ICH, cSAH, or both 21.4% (95% CI 16.7-26.9), ischemic stroke 5.1% (95% CI 3.1-8) and death 8.3% (95% CI 5.6-11.8). In multivariable models, there is evidence that patients with probable CAA (compared to possible CAA) had a higher risk of ICH (HR 8.45, 95% CI 1.13-75.5, p = 0.02) and cSAH (HR 3.66, 95% CI 0.84-15.9, p = 0.08) but not ischemic stroke (HR 0.56, 95% CI 0.17-1.82, p = 0.33) or mortality (HR 0.54, 95% CI 0.16-1.78, p = 0.31). CONCLUSIONS: Patients with cSAH associated with probable or possible CAA have high risk of future ICH and recurrent cSAH. Convexity SAH associated with probable (vs possible) CAA is associated with increased risk of ICH, and cSAH but not ischemic stroke. Our data provide precise risk estimates for key vascular events after cSAH associated with CAA which can inform management decisions