ANATOMY OF THE BRAIN

Anatomy of the Brain

Anatomy of the Brain

The brain, a bilaterally symmetric, soft, gelatinous structure surrounded by its meninges and enclosed in its bony cranium, is continuous with the spinal cord at the foramen magnum at the base of the skull. At birth the brain weighs less than 400 g, but by the beginning of the second year of life it has more than doubled in weight to 900 g. The adult brain weighs between 1,250 and 1,450 g, and demonstrates a gender differential, since brains of males generally weigh more than those of females. This statement, however, should be tempered by the evidence that, in adults, the ratio of brain to body weight is greater in females than in males and that the increase in weight is due more to the proliferation of neuroglia than to the mitotic activity of neurons. An additional point of interest is that there does not appear to be a relationship between brain weight and intelligence.

Parkinson's Disease

Parkin is the second Parkinson's disease gene (PARK2). Parkin mutations are typically detected in autosomal recessively inherited young onset parkinsonism with dystonia, sleep benefit, and the tendency to develop L-dopa induced dyskinesias, but some patients with Parkin mutations have a later age of onset (up to 65 years) and are clinically indistinguishable from patients with idiopathic Parkinson's disease. infection progression is substantially slower in patients with parkin mutations than in idiopathic, Lewy body Parkinson's disease.

Huntington's Disease

Polyglutamine diseases such as Huntington's infection, Kennedy's infection, dentatorubro-pallidoluysian atrophy (DRPLA), and some of the autosomal superiorly inherited spinocerebellar ataxias outcome from an increased number of CAG nucleotide does again that encode polyglutamine tracts inside the corresponding gene products. The various proteins display no sequence homology out-of-doors the polyglutamine tract, span distinct extents, have distinct cellular localisations and, where renowned, distinct ...