Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042373 (vascular disease)
 17,070 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The historical events in the evolution of Alzheimer's disease are reviewed, including the initial description by Alois Alzheimer and the subsequent controversy regarding the nosological specificity of this entity. The similarity of senile dementia and Alzheimer's disease is emphasized. The basis for the modern concept of Alzheimer's disease as premature or accelerated aging is included in the review. The pathological correlates of the major categories of adult dementia have been described. The traditional criteria of neurofibrillary tangles and senile plaques have been re-evaluated using the current insight into these changes afforded by electron microscopy and biochemistry. The significance of amyloid has been described because it occurs within the senile plaque and also as the essential component of congophilic angiopathy. The new information regarding neuronal cell counts and the loss of choline acetyltransferase has been evaluated in terms of an indication of a pathogenic mechanism of Alzheimer's disease. The current understanding of normal pressure hydrocephalus, Creutzfeldt-Jakob disease, and multi-infarct dementia has been described. Brain biopsy in dementia has been described as having diagnostic, research, pathogenic, and prognostic value. The precautions involving the performance and handling of the biopsy have been stressed, particularly because these procedures involve conditions of possible slow virus etiology. The polemic for Alzheimer's disease as aging or slow virus infection has been summarized. At this time a consideration seems justified that Alzheimer's disease is an age-related, slow virus disease due to a hitherto unknown immune defect. Aging as an etiological agent must be clarified before Alzheimer's disease, in any form, can be considered to be an inevitable consequence of longevity.
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PMID:Adult dementia: history, biopsy, pathology. 37 82

Senile dementia of the Alzheimer type is becoming one of the most common of the malignant diseases as our society ages. Currently, research has identified several pathophysiological changes, including the bihelical filament and the loss of the enzyme choline acetyltransferase from the cortex. Although genetic factors play some role in this disease, the important environmental risk factors have not yet been identified and there is, at present, no specific treatment. The second most common cause of dementia, cerebrovascular disease, produces dementia only when there is destruction of brain tissue, as in individuals who have multiple strokes or who have hypertensive vascular disease leading to multiple lacunae. In both multi-infarct dementia and in the lacunar state, hypertension appears to play a greater role than it does in other forms of vascular disease. Many of the other causes of dementia, including normal pressure hydrocephalus, CNS infections or tumors, metabolic disorders produced by thiamine or vitamin B12 deficiency or thyroid dysfunction, are often reversible. Every patient, whatever the age, with a developing dementia deserves a thorough workup to identify these treatable disorders.
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PMID:Dementias. 75 96

The neuropeptide galanin is known to inhibit the evoked release of acetylcholine in ventral hippocampus of the rat. Co-localization of this peptide with choline acetyltransferase in neurons of the cholinergic septal nuclei has been demonstrated in the rat and non-human primate. The severe deficiency of the cholinergic hippocampal projection system arising mainly from the vertical limb nucleus of the diagonal band of Broca, also referred to as Ch2 region, is a constant finding in Alzheimer's disease, a disorder which is neuropathologically characterized by the appearance of senile plaques, neurofibrillary tangles and congophilic angiopathy in neo- and archicortical structures. In the present study for the first time galanin immunoreactivity in the human Ch2 region is morphologically investigated and related to the severity of hippocampal plaques and neurofibrillary tangles in Alzheimer's disease. An inverse relationship between decreasing galanin immunoreactivity in the Ch2 region and amounts of senile plaques and neurofibrillary tangles in the hippocampus is indicated. Considering the cholinergic deficiency in Alzheimer's disease as a secondary phenomenon to primary cortical and hippocampal lesions, and realizing the inhibitory effect of galanin upon acetylcholine release in hippocampus, this preliminary study suggests that a decreased galanin immunoreactivity in Ch2 in Alzheimer's disease, reflects a possible negative feedback mechanism to a degenerating cholinergic projection system.
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PMID:Galanin-like immunoreactivity within Ch2 neurons in the vertical limb of the diagonal band of Broca in aging and Alzheimer's disease. 247 41

Dementia of the Alzheimer type (DTA) is the most common form of adult-onset dementia. The clinical features of the disease include progressive memory defect, intellectual impairment and behavioral disturbances. The number of patients suffering from DTA is increasing dramatically, due to the growing proportion of old people. DTA therefore is a major public health problem. Brain lesions include several histopathological changes (mostly in the cerebral cortex and hippocampus): neurofibrillary tangles, senile plaques, granulo-vacuolar degeneration, Hirano bodies, angiopathy, loss of nerve cells. Postmortem brain examination reveals characteristic neurochemical deficits. The most consistent reduction in neurotransmitter-synthesizing enzyme observed so far is a reduction in choline acetyltransferase activity, suggesting a cholinergic deficit. However, other deficits involving noradrenaline and somatostatin have also been reported. Several hypotheses (genetic, viral, toxic, immunologic, metabolic) have been put forward in order to explain DTA. The relationship between these hypotheses and the neurochemical deficits is still unclear, but the existence of characteristic neurotransmitter-related deficits allows specific therapeutic trials.
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PMID:[Alzheimer's type dementia: recent data]. 613 79

Choline acetyltransferase activity was measured postmortem in five brain regions to determine if such activity provided biochemical support for clinical and pathological subgrouping of Alzheimer's disease. Seven patients with Alzheimer's disease were divided into groups based on age at onset, severity of neuropathological changes, history of myoclonus, family history of dementia, cerebellar amyloid plaques, and congophilic angiopathy. Thirty-two age-matched normal control subjects and 17 neurological control patients with Huntington's disease were also studied. Patients with early-onset and late-onset Alzheimer's disease did not differ in the clinical duration of their disease. Choline acetyltransferase activity was significantly lower in patients with early-onset Alzheimer's disease than in age-matched control subjects in frontal cortex, temporal cortex, hippocampus, and cerebellum. In contrast, choline acetyltransferase activity in patients with late-onset Alzheimer's disease was significantly lower than in age-matched control subjects only in hippocampus. There was a tendency for choline acetyltransferase activity to be lower in cortex from patients with early-onset Alzheimer's disease compared with cortex from the late-onset group, and this difference was significant in temporal cortex. Choline acetyltransferase activity was also measured in the substantia innominata from 9 patients with Alzheimer's disease and 5 age-matched control subjects. Subjects with early-onset Alzheimer's disease had significantly lower choline acetyltransferase activity in substantia innominata than did control subjects. Patients with Alzheimer's disease and a history of myoclonus had significantly lower choline acetyltransferase activity than did affected patients without myoclonus. Multivariate regression analysis showed myoclonus to be the single best predictor of low brain choline acetyltransferase activity. These results provide further evidence for clinical, pathological, and biochemical heterogeneity in Alzheimer's disease.
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PMID:Alzheimer's disease: choline acetyltransferase activity in brain tissue from clinical and pathological subgroups. 622 76

beta-Amyloid protein (beta-AP) deposits, analoguous to those found in Alzheimer's disease (AD) are observed in the brain of aging Microcebus murinus. Because choline acetyltransferase (ChAT) activity and somatostatin (SRIH) content are consistently decreased in AD, we tested whether such changes could be observed in middle aged to aged Microcebus cerebral cortex and whether they were accompanied by beta-AP deposits. A positive correlation was observed between age and ChAT activity. By HPLC, SRIH immunoreactivity eluted as four peaks, two of which being identical with SRIH-28 and SRIH-14 while the other two likely represented precursor forms. Cortical SRIH content was not significantly affected by age. ChAT activity and SRIH content were not significantly correlated. Amyloid angiopathy was observed in every brain examined and the presence of cortical lesions analoguous to senile plaques observed in the oldest case only which did not demonstrate important alterations in ChAT and somatostatin levels.
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PMID:Choline acetyltransferase and somatostatin levels in aged Microcebus murinus brain. 789 28