Search PubMed⌕ Search

Biomedical subjects

B Lechevalier

Publications and source records attributed to B Lechevalier.

At least 55 records · Page 3Linked to original sources
PubMed1991

[Accidental poisoning with podophyllin: a case with study of peripheral nerve].

A 53 year-old veterinary surgeon accidentally ingested 0.8 g of podophyllin. Twelve hours later, he was deeply comatose, with clinical and EMG signs of extensive axonal sensorimotor and autonomic peripheral neuropathy. In addition, transient bone marrow and hepatic toxicity occurred. The coma lasted 2 weeks. Systemic and neurological disturbances started to improve at 3 months post-onset, but the patient died four months later from gastro-intestinal bleeding. Sural nerve biopsy showed loss of myelinated fibers and signs of axonal degeneration with type E teased fibers. The cytoplasm of Schwann and endothelial cells was vacuolated and swelled. Diffuse interstitial aedema was noted. Podophyllin acts as a spindle poison, binds microtubular proteins and inhibits axoplasmic flow.

Accidents↗
PubMed1991

[Spinal lipoma associated with a neuromuscular hamartoma. Report of one case].

A 6 year-old boy with urinary incontinence, sensory loss and spastic weakness in lower limbs underwent surgical repair for low-lying spinal cord ending in an intradural lipoma. Within the lipoma, bundles and fascicles of striated muscles fibers were intimately associated with nerve fibers. This extremely rare histological appearance has been reported as benign "triton tumor". Our case allows a discussion of its histogenesis.

Child↗
PubMed1990

EEG cartography before and after visual stimulation: a group study with descriptive non-parametric analysis of EEG data.

Ten right-handed students were submitted to a protocol of cognitive visual stimulations based on six successive sequences: EC1, EO, B1, B2, B3, EC2. Following a first "eyes closed" (EC1) multiple EEG recording (16 EEG leads, plus polygraphy), and an "eyes-open" recording (EO) with central visual fixation, 60 computer-controlled slides were presented successively for each of three successive recordings (B1, B2, B3) before the last "eyes-closed" recording (EC2). In B1, the subjects were asked to look at the meaningful black and white drawings presented without comment. In B2, a second set of similar pictures was presented, with the advice to try to remember later on the visually projected slides. In B3, a memory recognition task was introduced with 20 slides coming from the B1 set, 20 from the B2 set, completed by 20 new slides. Each slide was presented for 10.24s. followed by a beep audio-signal indicating that the subjects should press electronic mouse knobs alternatively in B1, B2, and for indicating their answers in B3. After artifact rejection, EEG spectral analysis was followed by parametrization and group studies applying Fisher non-parametric paired exact probability tests. Nine comparisons were computed: EC1-EC2, EC1-EO, EC2-EO, EO-B1, EO-B2, EO-B3, B1-B2, B1-B3, B2-B3. A statistical strategy of descriptive inter-individual non-parametric. Fisher tests was undertaken, together with computation and mapping of averaged spectral parameter differences (mean amplitudes and frequencies, mean amplitudes %, resonance coefficients) for raw EEG, delta, theta, alpha, alpha 1, alpha 2, beta 1 and beta 2 frequency bands and probability maps.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Identification and discrimination disorders in auditory perception: a report on two cases.

Auditory perception was investigated in two brain-damaged subjects. The first patient had a left temporoparietal ischaemic lesion. He presented a right-ear extinction in dichotic tasks, as well as difficulties in understanding and repeating verbal material and impaired identification of melodies. All discrimination tests were well performed. The second patient had a right capsulolenticular and frontal ischaemic lesion. He presented a left ear dichotic extinction and severe difficulties in discrimination of environmental sounds and melodies but no major difficulty in naming and identification. From these results, it is hypothesized that identification and discrimination involve distinct mechanisms within the processing of auditory stimuli, and that they may be selectively disrupted in brain-damaged subjects.

Adult↗
PubMed1990

Word-association responses and severity of dementia in Alzheimer disease.

To test the impairment of semantic memory in Alzheimer Disease, two groups of patients (one French and one American) were given a free-word-association task. Analysis showed a strong correlation between the scores of the Mini-Mental State Examination and an index of commonality of responses in both groups. As the severity of dementia increased, Alzheimer patients were less likely to give common responses. Our results are consistent with those of previous studies showing a relationship between dementia severity and impairment in semantic memory in Alzheimer Disease.

Aged↗
PubMed1989

Regional cerebral blood flow during comprehension and speech (in cerebrally healthy subjects).

Regional cerebral blood flow (rCBF) was measured by the xenon-133 inhalation method in 10 cerebrally healthy subjects at rest and during linguistic activation tests. These consisted of a comprehension test (binaural listening to a narrative text) and a speech test (making sentences from a list of words presented orally at 30-s intervals). The comprehension task induced a moderate increase in the mean right CBF and in both inferior parietal areas, whereas the speech test resulted in a diffuse increase in the mean CBF of both hemispheres, predominating regionally in both inferior parietal, left operculary, and right upper motor and premotor areas. It is proposed that the activation pattern induced by linguistic stimulation depends on not only specific factors, such as syntactic and semantic aspects of language, but also the contents of the material proposed and the attention required by the test situation.

Adult↗
PubMed1989

Auditory agnosia with relative sparing of speech perception.

We report a case of auditory agnosia in which the initial clinical picture began with generalized auditory agnosia for verbal and non verbal sounds, but rapidly changed to a selective auditory agnosia confined to the perception of non verbal sounds. CT scanning and MRI did not demonstrate cortical or subcortical damage, except for bilateral ventricular enlargement. The patient was submitted to audiological investigations including physical and psychoacoustic studies. Deficits were revealed during the decay and loudness discrimination test, but no temporal auditory acuity deficit was observed. The results of these studies are discussed in relation to the clinical picture. Also the dissociation between verbal perception and non verbal perception is discussed.

Adult↗
PubMed1989

Infarct of the anterior limb of the right internal capsule causing left motor neglect: case report and cerebral blood flow study.

A sixty-nine year old hypertensive man had left motor neglect following an infarct of the anterior limb of the right internal capsule. He also had left auditory extinction on verbal dichotic listening and a sligh constructional apraxia. Regional cerebral blood flow (CBF) was measured at rest with Xenon 133 inhalation and was found to be slightly decreased in a diffuse fashion. Motor activation of the right hand resulted in an increase of CBF in the contralateral superior rolandic area, whereas no such increase was found during motor activation of the left hand. This lack of cortical CBF increase on contralateral motor activation is interpreted as a consequence of the failure of some corticosubcortical connexions involved in motor arousal. The specifically dynamic appearance of regional CBF abnormalities, i.e. during selective activation as opposed to rest measurements, is consistent with the functional character of neglect.

Aged↗
PubMed1989

[Familial myopathy with "cytoplasmic body" (or "spheroid") type inclusions, disclosed by respiratory insufficiency].

Three patients, 72, 45 and 18 years old belonging to 3 successive generations presented with respiratory insufficiency. The clinical onset was at about 40 years of age in the two older patients and at 18 years in the youngest one. Serum enzymes of muscle origin were within normal range as well as leucocyte maltase activity. The muscle biopsy in all three patients showed numerous cytoplasmic (spheroid) bodies within type I muscle fibers. Familial cytoplasmic body myopathy with familial incidence has rarely been reported and still more rarely has been revealed by respiratory insufficiency in adult life.

Adolescent↗
PubMed1989

[Neurologic forms of Lyme disease. 12 cases].

Twelve cases of Lyme's disease with neurological complications are reported. Seven patients had meningoradiculitis of the Garin-Bujadoux-Bannwarth type, with facial palsy in 2 cases. In 1 case the radiculitis involved only the cauda equina. Two more patients had meningomyelitis. Of the remaining 3, 1 had subacute inflammatory polyneuritis with albumino-cytologic dissociation, 1 had probable dorsal epiduritis, and the last one developed parkinsonism and communicating hydrocephalus after an otherwise classical meningoradiculitis. Three patients recalled a tick bite but only one a cutaneous eruption. No arthritis or cardiac involvement were observed. In 2 cases the CSF contained pseudo-neoplastic cells. Severe pain was a prominent feature in most cases. Pain consistently and rapidly improved on high-dose intravenous penicillin, while other signs or symptoms (e.g. paresthesias or fatigue) often lasted several months. Parkinsonism and hydrocephalus were not influenced by penicillin, and both required specific therapy. Isolated neurological (both central and peripheral) involvement is not unusual in Lyme's disease and may give rise to a wide range of signs and symptoms. This diagnosis is to be considered even when other features of Borrelia burgdorferi infection are lacking.

Adult↗
PubMed1989

[Chronic spinal amyotrophy involving the upper limbs in young adults (O'Sullivan and McLeod syndrome). MRI study of the cervical spinal cord].

In 5 cases of sporadic spinal muscular atrophy in young adults the muscular atrophy was localized in the hands and forearms. Age at onset ranged from 7 to 20 years. The duration of the disease was less than 5 years in 3 patients and more than 15 years in 2. Electromyography showed neurogenic anomalies in all wasted muscles, denervation potentials being also present in the proximal muscles of the upper limbs and distal muscles of the lower limbs in 2 patients. Motor nerve conduction velocity and sensory nerve action potentials were normal. Advantages of a topographic classification of the distal form of chronic spinal muscular atrophy are discussed. Spinal cord MRI was performed in 4 patients with a 0.5 Tesla superconducting magnet using surface coils, using a T1-weighted spin-echo technique (ET 26 ms; RT 500 ms) and a T2-weighted spin-echo technique (ET 90, 180 ms; 2,000 ms). With the T1 technique, axial MRI sections 7 to 9 mm thick of spinal cord showed a normal image between C1 and C4, and a flattened image between C5 and T1. This was considered as a possible spinal cord segmental atrophy.

Adolescent↗
PubMed1989

[Detection of nosocomial infections: a proposal of a protocol for a prospective study].

If meant to be effective, the detection of nosocomial infections demands considering the means that should be used for a daily gathering of necessary complete information. An experiment led in a medical intensive care unit have suggested the elements of such a gathering work. This must be prospective and aimed to relate the frequency, more that the importance of nosocomial infections. It will be carried by a willing and specialized nurse, and will be limited to the necessary warning signs only. As a rule, the information linked to the infection causes will not be looked for. Finally, a special care will be given to ensure a good feedback to the clinician, which is the main purpose of that work. Yet, such an information gathering protocol has to be flexible, and it is even one of its survival conditions regarding the variety of means and requirements inherent of each department.

Clinical Protocols↗
PubMed1988

[Alzheimer's disease with early association of a hemi-parkinsonian syndrome].

A 66 year-old woman presented with severe memory disorders followed several months later with tremor of Parkinsonian type of the right upper limb totally relieved by treatment with levodopa-benserazide. Four years later she was admitted with memory disturbances, temporospatial disorientation, constructional and ideatory apraxia, dressing apraxia and language difficulties. Eight years later she had become bed-ridden, with deviation of head and eyes towards the left, hypertonus tremor and stereotyped movements. Neuropathologic examination showed neuronal loss in substantia nigra and left locus ceruleus, dorsal nucleus of the pneumogastric nerve and Meynert's basal nuclei on both sides. Neurofibrillary tangles affected the peri-aqueductal grey matter and Lewy's bodies were observed in the substantia nigra. Neurofibrillary tangles and granulovacuolar degeneration together with senile plaques were numerous in the hippocampus, but senile plaques and neurofibrillary tangles were rare in the remainder of the cortex. Combined Alzheimer's disease and Parkinson's disease could be due to simple coincidence, one of the diseases possibly predisposing to the appearance of the other.

Aged↗