Functional connectivity alterations associated with literacy difficulties in early readers.

The link between literacy difficulties and brain alterations has been described in depth. Resting-state fMRI (rs-fMRI) has been successfully applied to the study of intrinsic functional connectivity (iFc) both in dyslexia and typically developing children. Most related studies have focused on the stages from late childhood into adulthood using a seed to voxel approach. Our study analyzes iFc in an early childhood sample using the multivariate pattern analysis. This facilitates a hypothesis-free analysis and the possible identification of abnormal functional connectivity patterns at a whole brain level. Thirty-four children with literacy difficulties (LD) (7.1 ± 0.69 yr.) and 30 typically developing children (TD) (7.43 ± 0.52 yr.) were selected. Functional brain connectivity was measured using an rs-fMRI acquisition. The LD group showed a higher iFc between the right middle frontal gyrus (rMFG) and the default mode network (DMN) regions, and a lower iFc between the rMFG and both the bilateral insular cortex and the supramarginal gyrus. These results are interpreted as a DMN on/off routine malfunction in the LD group, which suggests an alteration of the task control network regulating DMN activity. In the LD group, the posterior cingulate cortex also showed a lower iFc with both the middle temporal poles and the fusiform gyrus. This could be interpreted as a failure in the integration of information between brain regions that facilitate reading. Our results show that children with literacy difficulties have an altered functional connectivity in their reading and attentional networks at the beginning of the literacy acquisition. Future studies should evaluate whether or not these alterations could indicate a risk of developing dyslexia.

Carcinoma escamoso de uretra metastático / Metastasic urethral squamous-cell a cancer

El carcinoma primario de uretra es una neoplasia poco común, constituyendo menos del 1% de los tumores genitourinarios. Éste es más habitual en el sexo femenino, en una proporción 4:1, apareciendo en la sexta o séptima década de la vida, siendo el tipo histológico más frecuente el carcinoma de células escamosas. Los primeros signos y síntomas son más propios de estenosis benigna de uretra que de malignidad. El periodo entre los primeros síntomas y el diagnóstico suele ser de alrededor de tres años. Por consiguiente la mayoría de estos tumores son localmente avanzados en el momento del diagnóstico y a pesar de ser sometidos a tratamientos agresivos tiene mal pronóstico. El tratamiento depende del estadio y la localización de la lesión. Debido a la rareza de esta neoplasia no existe un consenso de tratamiento, pero parece ser que éste debe ser multimodal, con cirugía, radioterapia y quimioterapia. Presentamos el caso de un varón de 80 años afecto de un carcinoma escamoso de uretra, localmente avanzado en el momento del diagnóstico. Ante la imposibilidad de recibir tratamiento quirúrgico fue tratado con quimioterapia más radioterapia, presentando al poco tiempo progresión precoz de la enfermedad (AU)

Urethral cancer is an infrequent pathology, less than 1% of the genitourinary tumors. It is more frequent in women (4:1), in the sixth or seventh decade of life. The most frequent histology being squamous cell carcinoma. First signs and symptoms usually are more attributable to benign stricture disease, rather than malignicy. The interval between the onset of symptoms and diagnosis may be as long as three years. Therefore most of these tumors are locally advanced at the time of diagnosis with generally poor prognosis despite aggressive treatment. Therapeutic management varies with the stage and location of the lesion. Because of the rarity of this pathology, no consensus has been reached on treatment modalities, but seems to be that must be a multimodal one, including surgery, radiotherapy and chemotherapy. We present the case of an 80 year-old male, with a diagnosis of urethral squamous-cell cancer, locally advanced at the time of diagnosis. Surgery was not feasible. The patient underwent chemotherapy and radiotherapy with evidence of quick progression thereafter (AU)