Movement Disorders

Parkinson’s disease. Cardinal features of Parkinson’s disease are rigidity, slowness of movement and tremor, postural instability being another cardinal sign. Blepharospasm, weird kinds of dystonia’s, weird kinds of striatal toes and odd things that happen when they swallow. But the point is that the early presentation, as you know, is an asymmetric presentation. Asymmetric of some combination of cardinal signs; tremor plus rigidity, or tremor plus slowness of movement, that progresses over the course of time. A rate of progression that has been thought to be somewhat stereotypical – but not necessarily so, since the natural history of Parkinson’s disease is such – some people have a rather benign course and some people have a rather aggressive course.
Disorders information
There are diseases where we see Lewy bodies elsewhere. The entity of diffuse Lewy body disease which is characterized by fluctuating mental states, tendency to visual hallucinosis, exquisite levodopa sensitivity in terms of its psychotoform manifestations, early dementia, etc. There is a pure autonomic failure variant that presents very much like Shy-Drager, also with predominant Lewy bodies both in the nigra and elsewhere. And if you turn it around, there have been cases of what looks really like idiopathic Parkinson’s disease, that entity described by Parkinson in 1817 in which, if you study the nigra, alas there are not Lewy bodies. How curious. This tends to happen in folks who have that autosomal dominant familial form of Parkinson’s disease, that is characterized by relatively early onset. Definition of early onset, before the age of 40.

The familial study, the work of Polly Meropolis, in which they find a linkage in familial clusters, the so-called gene from the original report in which they find linkage to the long arm of chromosome 4. This is a missense mutation, alanine substitution giving rise to a change in the associated protein product, which is something called alpha syncline. This is only in familial cases. In sporadic cases, even in young onset sporadic cases – the thing that looks the most like this autosomal parkinsonism – there was no association to chromosome 4. The significance, in other words, of these genetic findings for sporadic Parkinson’s disease is most unclear and to be sure there has been no linkage identified for the sporadic form of this disease. What the significance of this alpha syncline finding is, interestingly, it may be that the particular amino acid substitution in question changes this bugger protein from something that tends to aggregate in a certain way to beta pleated sheet formation, so maybe it has something to do with amyloid deposition and maybe it has something to do with the formation of the Lewy body in idiopathic disease. But that’s at a level of speculation. It is not corroborated by data as yet.

2 Responses to Movement Disorders

  1. […] shoot for about 1 gram of levodopa, but that’s up to individual taste. A gram or gram and a half. Movement disorders Posted in Movement Disorders on November 14th, 2007 RSS 2.0 […]

  2. […] then is a review of our current … sort of a quick review of where we stand in the treatment of Parkinson’s disease, and I’ll run through these points. I’m sure all of you are familiar with these. The first […]

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