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Biomedical subjects

H Petit

Publications and source records attributed to H Petit.

At least 55 records · Page 3Linked to original sources
PubMed1997

Late onset familial dystonia: could mitochondrial deficits induce a diffuse lesioning process of the whole basal ganglia system?

BACKGROUND: Striatal necrosis has been related to various clinical syndromes, with acute or chronic progression, and juvenile or late occurrence, but the most common type is Leigh's encephalopathy. METHODS: Between 1967 and 1995, six out of seven related patients with chronic familial dystonia were examined. MRIs were performed in four, between 1992-1994. The seven members, affected over three generations, were the father, three daughters (one surviving), and three surviving grandsons. RESULTS: The leading symptoms were gait disorders and dystonia in all, dysarthria in six, verbal and motor stereotypies in two, and parkinsonian and cerebellar signs in three. Optic neuropathy was found in three. A frontal lobe syndrome without amnesia occurred in two. Symptoms occurred between the second and the fifth decade, with progressive deterioration. Magnetic resonance imaging, performed in four, showed in the two patients with severe neurological signs diffuse striatopallidal abnormal hyposignal (comparable with CSF signal) in T1 weighted images, suggesting extensive necrosis of the striatum and pallidum, associated with thalamo-subthalamo-rubro-dentato-nigral and substantia innominata hypersignals in T2 weighted images suggesting gliosis in these respective areas. The same images were described to a lesser extent in a third patient. Concentrations of lactate in CSF and serum were normal in three. Muscle biopsy, performed in four, was shown to be normal. Enzyme histochemistry showed complex I, III, and IV deficiency in surviving patients. CONCLUSION: This familial dystonia of chronic progression may be related to basal ganglia necrosis or gliosis, associated with alterations in the respiratory chain. These metabolic alterations probably play a part in the pathophysiology of these unusual brain lesions.

Basal Ganglia↗
PubMed1997

Association between medial temporal lobe atrophy on CT and parietotemporal uptake decrease on SPECT in Alzheimer's disease.

OBJECTIVES: Alzheimer's disease is the most frequent cause of degenerative dementia. Despite the available diagnostic criteria, improvement of diagnosic accuracy is still required. The aim of this prospective study was to assess in a large population of patients referred to a memory clinic the diagnostic value of the combination of medial temporal lobe atrophy on temporal oriented CT and decreased temporoparietal uptake on HMPAO single photon emission tomography (SPECT). METHODS: The study was conducted in 125 patients aged 51-93: 64 with probable Alzheimer's disease (Mean (SD) mini mental state examination (MMSE)=18.34 (6.93)), duration of disease=6.48 (2.93) years, 13 possible Alzheimer's disease (MMSE=21.58 (5.48), duration of disease=6.08 (2.56)), 48 patients with miscellaneous memory disorders (MMSE=21.98 (6.10), duration the disease = 6.85 (3.91)). RESULTS: For the diagnosis of probable Alzheimer's disease, the sensitivity of this association was 0.56, the specificity 0.93, the positive predictive value 0.95, and the negative predictive value 0.45. The diagnosic accuracy was 0.68. Both medial temporal atrophy and parietotemporal decrease in uptake were present in four of 13 patients with possible Alzheimer's disease and 11 of 48 with miscellaneous memory disorders. The association was absent in 27 of 29 patients with frontotemporal dementia. In mild stages (MMSE>18; n = 32), the sensitivity of the association was 0.34, the specificity 0.93, the positive predictive value 0.85, and the negative predictive value 0.57. The diagnosic accuracy was 0.53. CONCLUSION: This association, although not sensitive, helps to select patients with high probability of Alzheimer's disease at an early stage which can be of interest for clinical and research purposes.

Aged↗
PubMed1997

Frontotemporal dementia: its rediscovery.

Frontotemporal dementia (FTD) is the second most frequent degenerative cause of dementia. Although described for more than a century, it remains often misdiagnosed, mistaken for Alzheimer's disease or psychiatric disorders, which is prejudicial to care and research. It is a clinical syndrome corresponding to at least three histological entities: (1) Pick's disease, (2) non-specific frontotemporal degeneration, (6 times more frequent), and (3) frontal lobe abnormalities associated with motor neurone disease. It never corresponds to Alzheimer pathology. It must be suspected in patients with behavioural dyscontrol predating memory impairment, without spatial disorientation and normal EEG.

Alzheimer Disease↗
PubMed1997

Contrast echocardiography in coronary artery diseased patients: effect of systemic and pulmonary artery pressures on left heart opacification after intravenous injection of Albunex.

BACKGROUND: Contrast echocardiography is a useful tool for assessing repeatedly patients with coronary artery disease. Nevertheless, elevated pulmonary artery and systemic blood pressures likely to be associated with cardiac ischemia may limit the left ventricular opacification (LVO) because of the microspheres' sensitivity to pressure. OBJECTIVE: To determine the effects of systemic and pulmonary artery blood pressures on LVO. METHODS: We performed 55 intravenous injections (0.08 and 0.22 ml/kg) of a new transpulmonary contrast agent (Albunex), during two separated exposures, into 20 cardiac ischemic patients while monitoring invasively their cardiac indexes, and intracardiac, systemic, and pulmonary artery blood pressures. LVO was graded qualitatively from faint to full. RESULTS: A logistic model with the grade of LVO as the dependent variable and a selection from among the dose, exposure, right and left atrial blood pressures, systolic systemic and pulmonary artery blood pressures (ranges 94-208 and 14-45 mmHg, respectively), cardiac index, stroke index, and pulmonary and systemic vascular resistances as the explanatory variables demonstrated that increasing the dose gives an increasing probability of LVO (P = 0.02) and that increasing the pulmonary artery pressure reduces that probability (P = 0.006). A decreased cardiac index tended also to be associated with decreased LVO. The systemic blood pressure and the pulmonary and systemic vascular resistances had no statistically significant effect on the grade of LVO. CONCLUSIONS: LVO after intravenous administration of Albunex is dose-dependent and limited by an elevated pulmonary artery pressure. These data suggest that one should use higher doses for cardiac ischemic patients with elevated pulmonary artery pressures and that use of Albunex has the potential to detect pulmonary hypertension in patients.

Adult↗
PubMed1997

[Mitochondrial anomalies in oculopharyngeal muscular dystrophy].

Oculopharyngeal muscular dystrophy (OPMD) was described by Taylor in 1915. This autosomal dominant inheritance affection begins at the age of 40-50 years associating bilateral ptosis and dysphagia. In 1980, Tome and Fardeau described rimmed vacuoles and typical intranuclear tubulo-filamentous inclusions in the muscle biopsy. We report two cases (brother and sister) of clinical and histological OPMD with mitochondrial abnormalities (Ragged red fibers) associated with classical OPMD lesions. Those observation remind the question already vised since a long time by some authors, of the signification of mitochondrial abnormalities in OPMD.

Female↗
PubMed1997

Positron emission tomography in dementia.

Positron emission tomography (PET) studies in dementia suffer from methodological differences. Most PET studies concern resting state metabolism in Alzheimer's disease and its correlations with neuropathology and neuropsychology. Only few clinically based PET studies on sensitivity and specificity of specific findings in specific dementing disorders have been reported. The role of PET in dementia for routine clinical purposes seems limited at present. Future studies should evaluate the potential of PET in preclinical diagnosis and to study treatment effects.

Alzheimer Disease↗
PubMed1997

[Bilateral 3rd cranial nerve palsy disclosing oligodendroglioma].

The patient was a 30 year-old man. He had no previous history. For several months he experienced a slowly progressive horizontal diplopia which was the expression of a bilateral third cranial nerve palsy with an intact intrinsic component. Muscular or neuro-muscular pathology as myasthenia was initially suspected but not confirmed. CT scan and MRI revealed an atypical left temporo-insular lesion which led us to discuss a chronic inflammatory pathology as sarcoidosis or a tumoral process. Finally cerebral biopsy showed a high grade oligodendroglioma. Symptomatology was attributed to infiltration of the peduncles from this tumor. Such a case has never been seen before. Early neuroradiological explorations would be useful in case of clinical suspicion of cranial nerve palsy.

Adult↗
PubMed1997

[Regressive leukoencephalopathy in chronic brucellosis].

A 59 year-old-man had ataxia and hemiparesis of progressive onset which resolved in a few weeks. CT scan and magnetic resonance imaging showed white matter multiple lesions. The cerebrospinal fluid was consistent with an inflammatory disease. The diagnosis of multiple sclerosis was evoked. However, the patient had chronic brucellosis and serological rates increased and decreased according to the clinical and radiological signs. Thus, encephalitis caused by brucellosis was evoked. The mechanism is assumed to be a demyelinating process caused by a deep focus reactivation.

Brucellosis↗
PubMed1996

Relevance of the quantification of apolipoprotein E in the cerebrospinal fluid in Alzheimer's disease.

Apolipoprotein E (Apo E), one of the major structural and functional apolipoproteins, has recently been implicated in the pathogenesis of Alzheimer's disease (AD). Several studies revealed that Apo E4 isoform is associated with the pathogenic process in AD. A significant reduction of cerebrospinal fluid (CSF) Apo E level in AD patients has been reported in two studies. To further investigate the physiopathological significance of such a variation of Apo E concentration in the CSF, we performed a quantification of Apo E by an enzyme linked immunosorbent assay (ELISA). There were no significant differences in CSF Apo E level between AD cases and control subjects or patients suffering from other neurological diseases. Gender, age and Apo E phenotype explained none of CSF Apo E concentration variability.

Aged↗
PubMed1996

[Behavior assessment in Alzheimer type dementia using the disruptive behavior questionnaire].

OBJECTIVES: We developed a disruptive behavior questionnaire designed for persons living close to the patient in order to assess behavior disorders in Alzheimer type dementia. METHODS: The study included 111 patients with criteria for diagnosis of Alzheimer type dementia. The questionnaire was used to assess the patients 15 days after withdrawal of psychotropic drugs. A partially-structured interview was also conducted by a psychiatrist in 20 cases. RESULTS: There was no relationship between the different behavior disorders and the mini-mental-state score or the social and cultural situation. Answers to the questionnaire and responses given during the interview were nearly identical. CONCLUSION: There has been little effort to assess behavior disorders compared with cognitive disorders in patients with Alzheimer type dementia. Behavior assessment should be an integral part of patient evaluation since cognitive and non-cognitive disorders are independent and certain therapeutics may be effective in behavior disorders.

Aged↗
PubMed1996

Atrial natriuretic factor secretion: a role for atrial systolic ejection force?

The increase in plasma concentration of atrial natriuretic factor in heart transplant patients has not been fully elucidated. Besides an eventual pressure or volume overload leading to passive atrial distension, the atrial tension developed during atrial systole, or atrial ejection force, which may be increased by the transplantation procedure, is an important determinant of atrial natriuretic factor release. We therefore determined the plasma concentration of atrial natriuretic factor and the maximal atrial ejection force in 15 heart transplant patients and 8 controls, matched for age and body mass. Atrial ejection force, as defined as the force exerted by the left atrium to accelerate blood into the left ventricle during atrial systole, was obtained using combined two-dimensional imaging and doppler echocardiography. Serum creatinin concentrations, heart rate [91.9 (SD 13.2) vs 71.8 (SD 10.9) beats.min-1], mean arterial blood pressure [103.9 (SD 9.8) vs 87.4 (SD 5.8) mmHg, 13.85 (SD 1.31) vs 11.65 (SD 0.77) kPa], left ventricular posterior wall thickness and interventricular septum thickness were higher in heart transplant patients compared to controls. Plasma concentration of atrial natriuretic factor was also elevated in heart transplant patients [63.9 (SD 18.1) vs 34.0 (SD 3.2) pg.ml-1; P < 0.001]. In contrast, although the left atrial area was greater in heart transplant patients [28.2 (SD 4.8) vs 15.8 (SD 2.5) cm2; P < 0.001], mitral area, transmitral Doppler A-wave maximal velocity and atrial ejection force were similar in transplant and in control patients [7.7 (SD 3.5) vs 8.9 (SD 2.8) kdyn, 77 (SD 35) vs 89 (SD 28)mN]. No significant correlation was observed between concentration of atrial natriuretic factor and atrial ejection force, either in heart transplant patients or in controls. Thus, the elevated plasma concentration of atrial natriuretic factor observed in these heart transplant patients was multifactorial in origin, and was considered to depend upon an hypersecretion rather than upon a decreased clearance rate. Moreover, it is suggested that the atrial ejection force was unlikely to have participated in this enhanced release of atrial natriuretic factor.

Adult↗
PubMed1996

White matter magnetic resonance imaging hyperintensity in Alzheimer's disease: correlations with corpus callosum atrophy.

We have previously demonstrated with MRI that as well as marked white matter involvement in late-onset Alzheimer's disease (AD), atrophy of the corpus callosum may also be present. This finding prompted us to study possible correlations between atrophy of the corpus callosum and white matter hyperintensity (WMH) and between white matter lesions and the severity of the disease. We compared the corpus callosum and white matter lesions on MRI from 15 AD patients and 15 controls. The white matter lesions were scored according to the Scheltens' rating scale. We found a significant reduction of the area of the corpus callosum and more severe white matter lesions in AD patients than in controls. Both atrophy of the corpus callosum and the severity of lesions depended mainly on the diagnosis of senile dementia of the Alzheimer type and on age but not on the diagnosis of presenile AD. We demonstrated a negative correlation between white matter lesions scores and areas of corpus callosum in AD patients and no correlation between the white matter lesions and the severity of the disease. We demonstrated that white matter lesions including WMH and atrophy of the corpus callosum are more frequent in AD than in controls. The predominance of white matter lesions in senile AD may be explained by the combination of aging and disease processes.

Aged↗
PubMed1996

Cognitive and psychiatric impairment in herpes simplex virus encephalitis suggest involvement of the amygdalo-frontal pathways.

The long-term neuropsychological and psychiatric sequelae of herpes simplex virus encephalitis (HSVE) and their relationship to the volume of temporal lesions and to amygdala and hippocampus damage remain undefined. We have conducted a prospective study of long-term sequelae in 11 patients with clinically presumed HSVE and detection of HSV DNA in the cerebrospinal fluid by polymerase chain reaction. Six months after encephalitis, patients underwent neuropsychological and language assessment. At the same stage, single photon emission computed tomography (SPECT) evaluated the occurrence of hypoperfusion with an index of asymmetry. MRI was used for the measurement of amygdala, hippocampus and cerebral lesions by two blind neurologists. The volume of the amygdala and hippocampus was compared with those of five controls, matched for age and level of education. Long-term memory disorders were seen in 6 patients, associated with the larger lesions and damage of at least two structures. Long-term behavioural changes with emotionalism, irritability, anxiety or depression were prominent in 7. Left prefrontal hypoperfusion appeared in 8 patients, associated with psychiatric disorders in 7 and left amygdala damage in 6. The reduction of amygdala and hippocampus volume was correlated with the overall volume of lesions. Different patterns of mesial temporal lobe damage occurred, involving either amygdala alone, or amygdala and hippocampus, but never hippocampus alone. MRI volumetric measurements in HSVE could be a good indicator of long-term prognosis. Persistant behavioural changes could be related to an amygdala and frontal dysfunction.

Acyclovir↗
PubMed1996

[Sarcoidosis of the central nervous system: clinical and radiological polymorphism].

Central nervous system (CNS) neurosarcoidosis was considered to be infrequent. Clinical and radiological polymorphism explained the delay before diagnosis. With magnetic resonance imaging (MRI), diagnosis is more easily performed, especially in paucisymptomatic cases. A review of the most important clinical and radiological studies and three personal cases are reported. This underlines variable characteristics of hemispheric localizations, especially pseudotumoral forms.

Adult↗
PubMed1996

Generation effect in short-term verbal and visuospatial memory: comparisons between dementia of Alzheimer type and dementia of frontal lobe type.

Memory deficit is the predominant presenting symptom in dementia. To compare short-term memory (STM) deficit in early dementia of Alzheimer type (DAT) vs frontal lobe type (DFT), and determine the residual memory capacity for stimulation, the generation effect (the memory advantage of items generated rather than read) was tested on verbal and visuospatial STM in patients with DAT (n = 10), DFT (n = 9) and in age-matched normal controls (n = 12). The generation effect enhanced performance in all groups. However, the profile of STM deficit differed in the two dementias: verbal and visuospatial memory were both decreased in DAT vs verbal memory only in DFT. These results provide a further criterion for differentiating between DAT and DFT, and show that memory performance can be enhanced in early dementia using techniques such as the generation effect.

Aged↗