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P Davous

Publications and source records attributed to P Davous.

At least 19 recordsLinked to original sources
PubMed1996

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, genetic homogeneity, and mapping of the locus within a 2-cM interval.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently identified autosomal dominant cerebral arteriopathy characterized by the recurrence of subcortical infarcts leading to dementia. A genetic linkage analysis conducted in two large families recently allowed us to map the affected gene on chromosome 19 in a 12-cM interval bracketed by D19S221 and D19S215. In the present study, these first 2 families and 13 additional ones, including a total of 199 potentially informative meiosis, have been genotyped with eight polymorphic markers located between D19S221 and D19S215. All families were linked to chromosome 19. The highest combined lod score (Zmax = 37.24 at theta = .01) was obtained with marker D19S841, a new CAn microsatellite marker that we isolated from chromosome 19 cosmids. The recombinant events observed within these families were used to refine the genetic mapping of CADASIL within a 2-cM interval that is now bracketed by D19S226 and D19S199 on 19p13.1. These data strongly suggest the genetic homogeneity of this recently identified condition and establish the value of its clinical and neuroimaging diagnostic criteria. Besides their importance for the ongoing positional cloning of the CADASIL gene, these data help to refine the genetic mapping of CADASIL relative to familial hemiplegic migraine and hereditary paroxysmal cerebellar ataxia, conditions that we both mapped within the same chromosome 19 region.

Cerebral Arterial Diseases↗
PubMed1994

Transcortical alexia with agraphia following a right temporo-occipital hematoma in a right-handed patient.

We describe the case of a 51-year-old right-handed man who was affected by a transcortical alexia with agraphia and aphasia. Transcortical alexia produces errors in both reading and writing while copying is preserved. The patient had a severe alexia and was unable to read letters, words or sentences. Language examination showed mild aphasia with reduced fluency, intermittent paraphasia but a good comprehension and a normal repetition. Spontaneously and from dictation, writing was impaired by an agraphic jargon, but copying was excellent even though the patient was unable to read his own written production. There was no visual agnosia nor hemianopia. CT scan and MRI of the brain showed that there was a single right temporo-occipital hemorrhage but no lesion in the left hemisphere. Following surgical evacuation of the hematoma, the patient improved. One month after onset, his language was quite intact and reading was possible. We hypothesize that this particular syndrome was the result of a double disconnection: alexia would result from a disconnection of the right angular gyrus and the occipital associative areas by a subangular lesion; agraphia would result from a disconnection of the right angular gyrus and the semantic store, probably located in the right hemisphere.

Agraphia↗
PubMed1994

[Cerebral hemorrhage disclosing metastatic choriocarcinoma].

We report the case of a 28-year-old woman who presented with multiple episodes of cerebral bleeding secondary to a choriocarcinoma with brain, lung and abdominal metastases, which had been partially treated 1 year before. The diagnosis was confirmed by a-high serum beta HCG level. This case emphasizes the importance of suspecting an underlying choriocarcinoma and obtaining a serum beta HCG level in young women presenting with a cerebral haemorrhage.

Adult↗
PubMed1992

[Chorea disclosing polycythemia and renal adenocarcinoma].

A 79-year-old woman had chorea complicating polycythaemia. The polycythaemia and the chorea disappeared after surgical removal of a renal carcinoma. The literature on polycythaemic chorea is reviewed and its pathophysiology discussed.

Adenocarcinoma↗
PubMed1991

Senile dementia of the Alzheimer type: is there a correlation between entorhinal cortex and dentate gyrus lesions?

Senile plaques (SP) are one of the neuropathological hallmarks of senile dementia of the Alzheimer type (SDAT). In 14 patients affected with SDAT (over 74 years of age), thioflavine S, Tau and acetylcholinesterase (AChE) stainings demonstrated an increased density of SP in the outer two thirds of the dentate gyrus molecular layer. However, a wide range of SP density was observed among the cases. The molecular layer of the dentate gyrus is one of the termination site of the perforant pathway that originates in layers II and III of the entorhinal cortex. We have found that the number of AChE-, thioflavine S- and Tau-positive SP that accumulate in the dentate gyrus is positively correlated with the density of thioflavine S-stained neurofibrillary tangles in layers II and III of the entorhinal cortex. In contrast, a similar correlation is not found when using Tau immunolabeling of the entorhinal tangles. These observations show an association between the accumulation of AChE-positive SP in the dentate molecular layer and the lesions of the perforant pathway. Furthermore, they suggest that the density of SP in the dentate gyrus correlates with the late stages of neurofibrillary tangles formation (thioflavine S positive), but not with the early stages (Tau positive).

Acetylcholinesterase↗
PubMed1991

[Familial subcortical dementia with arteriopathic leukoencephalopathy. A clinico-pathological case].

A 54-year-old man died after a subcortical dementia that had developed over 7 years with focal neurological signs and a stepwise course. Clinical and radiological features were similar to those of Binswanger's disease but there was no vascular risk factor, especially no hypertension. Three similar cases had occurred in the family affecting the patient's mother, her brother and sister, suggesting an autosomal dominant hereditary disease. Postmortem examination disclosed an arteriopathic leukoencephalopathy. The white matter was mainly affected in the periventricular areas of the frontal and parietal lobes with myelin loss and pallor, sparing the U fibers. The vascular changes involved the small vessels and were not arteriosclerotic. There was severe thickening of the internal lamina and degradation products of the elastic fibers. There was no amyloid. This vascular leukoencephalopathy was different from Binswanger's disease and amyloid angiopathy. We think that the vascular lesions could correspond to a genetically transmitted specific degenerative pathology of the small arteries of the brain.

Aged↗
PubMed1991

[Mitochondrial encephalopathy affecting only the central nervous system].

A 32 year-old diabetic woman presented with an acute coma followed by epileptic seizures, aphasia and constructive apraxia. No ischemic lesion was demonstrated by CT scan and carotid angiograms. The other investigations showed sensorineural hearing loss, retinal degeneration, calcifications of the basal ganglia and lactic acidosis. The follow-up was marked by pseudo-dementia with personality disorders, memory deficits, behavioural changes, migrainous and epileptic features. Although there was no sign of muscular deficiency, a muscular biopsy showed characteristic ragged-red fibers and mitochondrial abnormalities at electron microscopy. The muscular biopsy enables us to classify this case as a mitochondrial encephalopathy similar to the MELAS syndrome. The stroke-like episodes are probably caused by a specific angiopathy involving the mitochondria of brain vessels.

Adult↗
PubMed1991

[Total deafness after multiple pontine infarctions. Dolichoectasia of the basilar trunk].

A 54 year-old man was affected by three successive infarctions in the vertebro-basilar territory. These infarctions were related to a dolichoectatic basilar artery visualized by arteriography and NMR. Deafness occurred first on the left side and then, after the third infarction, on the right side. The authors underline that deafness can be observed after a pontine infarction in the territory of the anterior inferior cerebellar artery. A dolichoectatic basilar artery can be the source of thrombotic or embolic strokes. Their prevention by antiaggregant or anticoagulant therapy is suggested.

Basilar Artery↗
PubMed1990

[Neuropathologic study of 50 cases of senile dementia].

Fifty brains from patients prospectively studied in a geriatric hospital (Charles Richet Study) were examined pathologically. The patients were senile (mean age: 85) and demented and had been clinically diagnosed as senile dementia of Alzheimer type (SDAT), vascular or multi-infarct dementia (VD), mixed dementia (MD). The whole brain was studied after formalin fixation and coronal sections. The senile changes were quantified in 6 neocortical areas, hippocampus and amygdala and subcortical structures after staining by thioflavine--S and Bodian's method. The other vascular and degenerative lesions were semiquantitatively studied. Three groups of patients were identified after microscopic examination: 1. SDAT (n = 27), 2. VD (n = 6), 3. MD (n = 15), 2 patients had no significant pathological correlate for dementia. Comparison of thioflavine S and Bodian's method in 30 cases showed the former to be more sensitive for the identification of senile plaques. In SDAT, 13/27 brains lacked neurofibrillary tangles in the neocortex. Amyloid angiopathy was observed in 78% of the brains but lacked in 5/6 cases affected by pure VD. Significant lesions of the substantia nigra were observed in 13 cases with typical features of Parkinson's disease in 2 cases. The locus coeruleus was affected mainly in SDAT cases (20/27) and in some cases of VD or MD (6/21). The raphe nuclei showed neuronal loss in 18% of the cases, mostly SDAT. In this series of cases, neocortical neurofibrillary tangles could be lacking in SDAT. Amyloid angiopathy was almost always present in SDAT and MD. Subcortical structures involved in cholinergic, noradrenergic and serotoninergic innervation of the cortex were more severely impaired in SDAT and MD than in VD. Mixed dementia was frequent in these very old demented patients. Clinical and pathological criteria are needed to identify this group of patients.

Aged↗
PubMed1989

Platelet [3H]-imipramine binding is not modified in Alzheimer's disease.

Platelet [3H]-imipramine binding was studied in patients with Alzheimer's disease and control subjects matched to the patients for age and sex. There were no differences in the binding parameters of [3H]-imipramine on platelet membranes from patients with Alzheimer's disease, when compared with the control group. These results suggest that [3H]-imipramine binding could be a useful tool to discriminate between demented and depressive patients in elderly populations.

Aged↗
PubMed1988

Serum neuron-specific enolase in senile dementia of the Alzheimer type.

The level of neuron-specific enolase (NSE), a glycolytic enzyme localized in neurons, was measured in the serum of patients with senile dementia of the Alzheimer type (SDAT). No difference was observed between NSE levels in SDAT and in healthy elderly controls of the same age range. No correlation was found between NSE levels and severity of the cognitive deficits. There was a marginally significant negative correlation between age and NSE, younger patients having higher NSE levels. The present results suggest that serum NSE is not a useful biological marker in the senile form of the dementia of the Alzheimer type.

Aged↗
PubMed1988

[Elementary test of concentration, orientation and memory. Application to the detection of dementia states in daily practice].

The authors present a french version of the Katzman short orientation memory concentration test. The 6 items of the test include 3 orientation questions, 2 mental control items and an address memory phrase. Time for administration is less than 5 minutes. This french version of the test has been validated as a measure of cognitive impairment in a population of 200 subjects including 140 patients without cognitive impairment and 60 demented subjects. As defined by a 10/11 cut-off score, sensibility and specificity for the diagnosis of dementia were 91 p. 100 and 95 p. 100 respectively. Correlation of the scores with those obtained by the Mini mental state was highly significant. This fast, easy and reliable test seems particularly suitable for the detection of cognitive impairment in clinical practice.

Aged↗
PubMed1988

Bilateral brain dysfunction during motor activation in type II schizophrenia measured by EEG mapping.

In this final electroencephalographic (EEG) mapping study of our series on motor dysfunction in neuroleptic-treated schizophrenic patients, we studied 10 right-handed patients with marked negative symptomatology [type II; raw score on the SANS (Munich version) 31.4 +/- 5.1]. Simple and multisensorimotor tasks involving both the dominant and nondominant hand were used for cortical activation. All tasks were referred to resting states obtained after specially designed relaxation procedures. In contrast to predominantly type I patients (SANS-MV score 12.3 +/- 4.9) of our previous EEG mapping studies, we found for resting states minor evidence (only) of increased power values in the frequency bands delta and theta. Furthermore, in contrast to signs of "left hemisphere dysfunction" and possible "compensatory right hemisphere overactivation" during motor tasks, which we discussed previously for our type I patients, we found for the type II schizophrenics a bilateral brain dysfunction. This consisted of "nonreactivity" in all frequency bands except alpha, in which, on the contrary, a "hyperreactivity" seemed to be present. In combination with evidence of bilateral hemispheric dysfunction in type II patients reported by other authors using EEG, evoked potentials, regional cerebral blood flow (rCBF) and magnetic resonance imaging (MRI) methods, this suggests that marked bilateral brain dysfunction may be correlated in schizophrenia with a clinical syndrome corresponding rather to the "negative pole" of the positive-negative dimension. In contrast, "left hemisphere dysfunction" and "signs of compensatory overactivation" seem to be linked more to a "positive" symptomatology. Finally, discrepancies of our EEG mapping and rCBF findings during motor activity suggest, speculatively, "uncoupling" between electrical and circulatory parameters in schizophrenia involving both hemispheres in type II, and predominantly the left hemisphere in type I, patients.

Adult↗
PubMed1988

Pharmacological modulation of cortisol secretion and dexamethasone suppression in Alzheimer's disease.

We have investigated the dexamethasone suppression of cortisol release in a group of 28 patients with senile dementia of the Alzheimer type (SDAT) after stimulation by physostigmine and clonidine, as compared with basal conditions. All patients but one had previously been evaluated with a depression symptom checklist and had submitted to a standard Dexamethasone Suppression Test (DST). SDAT patients showed normal baseline cortisol values measured at 4:00 PM. DST was reproducible, but nonsuppression did not appear to be a feature of the disease, nor of the dementia syndrome, although a majority of the most demented patients were found to be nonsuppressors. Physostigmine stimulated cortisol secretion in 20 of 24 cases, irrespective of the severity of dementia. Clonidine induced a secretion in 12 of 15 cases, but this was less than that observed after cholinergic stimulation. Physostigmine made cortisol release significantly less sensitive to the suppressive effect of dexamethasone than clonidine in SDAT. This double response should be tested as a possible predictor of a cholinergic therapeutic effect.

Aged↗
PubMed1988

[Quantitative analysis of the distribution of acetylcholinesterase-positive senile plaques in the hippocampal formation in patients with senile dementia of Alzheimer type].

Senile plaques (SP) are one of the major neuropathologic hallmarks of senile dementia of Alzheimer type (SDAT). The regional distribution of SP stained for acetylcholinesterase (AChE) has been quantified in the hippocampal formation of patients with SDAT. Consistent differences in plaque distribution and density were observed between different patients. SP were significantly more numerous in the outer dentate molecular layer, whereas their density was low in other hippocampal regions. The quantity of AChE positive SP seemed to correlate with the density of neurofibrillary tangles in the entorhinal cortex. The AChE positive SP had a pattern of distribution different from the one observed with Thioflavin S. These results are discussed in light of a possible sprouting of cholinergic septal afferents.

Acetylcholinesterase↗