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M Collard

Publications and source records attributed to M Collard.

At least 19 recordsLinked to original sources
PubMed1992

Expression and regulation of a proenkephalin beta-galactosidase fusion gene in the reproductive system of transgenic mice.

A fusion gene containing 3 kilobases of human proenkephalin 5'-flanking sequences and 1 kilobase of human proenkephalin 3'-flanking sequence and the easily visualized histochemical marker, Escherichia coli beta-galactosidase, was used to study the function of cis-regulatory elements within the human proenkephalin gene in transgenic mice. Here data are presented on expression and regulation of this fusion gene in the reproductive system of three independent lines of transgenic mice. Within the male reproductive system, the fusion gene is expressed in the proximal epididymis and in developing germinal cells but not in mature or elongating spermatids. In the female reproductive system, the transgene was expressed at low basal levels, but expression was dramatically stimulated in the ovary and oviduct by hormonal stimulation and pregnancy; additionally, expression was induced at the uteroplacental junction in pregnant mice. Taken together these observations suggest that critical sequences for expression and regulation of the proenkephalin gene within the reproductive system are contained within sequences of the construct.

Animals↗
PubMed1992

Contralateral disappearance of parkinsonian signs after subthalamic hematoma.

A man with Parkinson's disease (PD) suddenly developed a left hemiballismus, and the CT showed a hematoma of the right subthalamic nucleus. After the ballistic movements had disappeared, akinesia and the other parkinsonian signs did not reappear on the left. This clinical case confirms the involvement of the subthalamic nucleus in the akinesia of PD, as suggested by recent experimental data.

Aged↗
PubMed1992

[Myelitis caused by toxocara canis (larva migrans)].

A young woman presented with recurrent myelitis associated with persistent eosinophilia in blood and CSF. Specific serological procedures in blood and CSF led to the diagnosis of visceral larva migrans. The patient recovered after 21 days of treatment with diethylcarbamazine. To our knowledge, this is the second report of myelitis in the course of visceral larva migrans.

Adult↗
PubMed1991

Nuclear magnetic resonance T2 relaxation times in multiple sclerosis.

An original method was used to carry out the mathematical analysis of T2 transverse magnetization decay curves and the measure of T2 relaxation times on multiple sclerosis (MS) patients. The presumably normal white matter (WM) of these patients presented higher T2 relaxation times (98.6 msec), in comparison with that found in a population sample (88 msec). In this case, magnetization decay curves remain mostly monoexponential and are characterized by a single T2. On the other hand, areas of increased signal (AIS) curves are always better fitted by a biexponential function characterized by a short (82 msec) and a long (greater than 200 msec) T2. The spreading out of long T2 varies from one AIS to another in the same patient and among different patients; values of long T2 also vary with time, but without any correlation with the clinical state. In fact, no correlation was been established between relaxation times and clinical parameters. Quantitative MRI therefore enables a different approach to interpret MRI images; results suggest that several histobiochemical parameters play a role in the pathogenesis of an AIS and that MS is a dynamic and constantly evolving disease.

Adult↗
PubMed1991

[Recurrent aseptic meningitis in periodic disease or Mollaret's meningitis?].

A 33 year-old Sephardic Jewish man with familial mediterranean fever (FMF), presented during a 7 year period, 6 episodes of aseptic meningitis, improving within less than 24 h after spinal tap. Cerebrospinal fluid analysis showed a mixed leucocytic pleocytosis ranging from 100 to 1,000 cell/mm3. Spinal fluid cultures for bacteria, viruses and viral antibodies were always negative. Our case supports other reports showing that recurrent aseptic meningitis, although rare, may occur in FMF. It usually responds to treatment with colchicine, like other manifestations of the disease. FMF meningitis has been compared to Mollaret's meningitis whose cause is undetermined. However, Mollaret's meningitis, unlike FMF, is sporadic and ubiquitous, is not transmitted genetically and affects men and women equally. Moreover, in Mollaret's meningitis transient neurological abnormalities, such as signs of encephalitis have often been reported: polyserositis or associated amylosis are absent, there is no biological inflammatory syndrome, and in 65% of the patients the CSF contains specific large mononuclear-derived cells called endothelial cells. Such abnormalities have not been described in FMF.

Adult↗
PubMed1991

[Postures and abnormal paroxysmal movements during sleep: hypnogenic paroxysmal dystonia or partial epilepsy?].

In recent years, a differentiation has been made between two syndromes that are characterized by brief abnormal paroxysmal movements occurring principally at night: 1, hypnogenic paroxysmal dystonia (HPD), sometimes considered a particular form of dystonia similar to paroxysmal kinesigenic choreoathetosis, and 2, mesiofrontal epilepsy. Whether HPD is a distinct syndrome is not clear. Twenty-three patients, 11 men and 12 women, were hospitalized between 1985 and 1989 for examination of this type of abnormal paroxysmal movements (APM) occurring at night. In order to clarify the physiopathology of these abnormal nocturnal movement as focal epilepsy or a particular form of dystonia, we analyzed the personal and familial antecedents of all 23 patients, the polygraphic records during waking and sleep periods, and the results of neuroradiological examinations. Four patients were examined by positron emission tomography (PET) using i8F deoxyglucose. Symptoms first appeared between 3 and 28 years of age (M, 10.1) and developed over 1 to 20 years (M, 10.1). APM clearly occurred more commonly (greater than 90%) during sleep, usually during phases of slow-wave sleep. The sleeping patient opened his eyes and the motor signs then variously associated affective facial expression; axial postural modifications; tonic, dystonic or choreic postural movements of the limbs; pedalling; automatisms; disordered agitation and vocalization. The seizure was abruptly interrupted after 10 to 60 seconds. There was usually no postictal confusion. Thirteen patients clearly had clear epileptic antecedents: in 9, generalized tonic-clonic seizures; in 4, focal epileptic status. During nocturnal polygraphic recording, 6 patients presented a generalized seizure following a period of APM.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Breast tumor with myoepithelial cells. Apropos of a case report].

A case of malignant myoepithelioma of the breast is reported. Mammographic and echographic features are not typical. Diagnosis of this rare lesion mainly relies on histological and immunocytological findings. This potentially malignant tumor must be totally resected given the risk of recurrence. To the author's knowledge, this is the third report of a breast myoepithelioma that has metastasized.

Adult↗
PubMed1990

[Isolated paralysis of the ocular motor nerve caused by infarction of fascicular fibers].

We report the case of an 80 year-old woman who developed an unilateral brainstem infarction with a lesion of the intraparenchymatous fibres of the IIIrd cranial nerve. Intraaxial lesions of this nerve are usually part of the alternate paralysis syndrome. Our case might be the second since the report of Achard and Levi in 1901. Infarction limited to the fascicular fibres of the oculomotor nerve sparing the oculomotor nuclei results in characteristic clinical manifestations. This in turn results from the highly selective distribution of the terminal arterial territories in the midbrain.

Aged↗
PubMed1990

[Late diagnosis of congenital argininemia during administration of sodium valproate].

Congenital hyperargininaemia is a rare condition transmitted as an autosomal dominant trait. Following a one-year free interval, repeated vomiting, psychomotor regression and spastic paraparesis with talipes equinus progressively develop. The diagnosis, confirmed by arginine assays in blood and urine, is probably often missed. We report a case of homozygous arginase deficiency belatedly diagnosed at the age of 18 years, when treatment with sodium valproate (VPA) was instituted. This female patient presented with psychomotor regression since the age of 15 months and with paraparesis since she was 3 years' old. These symptoms rapidly became worse. At the age of 18 years, when she was bed-ridden, she was hospitalized for subintrant tonic seizures. EEG showed generalized, continuous spike-wave discharges at the rate of 3.5 c/s. Treatment with VPA was instituted. Five days later, she went into a state of stupor. Blood ammonia level was elevated at 362 mumol/l. VPA was discontinued, and this was followed by a regression of disturbances of consciousness and by a decrease in arterial ammoniaemia, although the ammonia levels remained high, fluctuating between 40 and 100 mumol/l. Several months after VPA treatment was interrupted, the patient had a second episode of stupor, and her ammoniaemia was 500 mumol/l. Serum amino acid chromatography showed hyperargininaemia at 501 mumol/l (N = 30-150 mumol/l). The diagnosis of arginase deficiency was confirmed by the rise of arginine in red cells, cerebrospinal fluid and urine and, above all, by the finding of a deeply depressed arginase activity in erythrocytes. In all cases of intolerance to VPA, arterial ammoniaemia should be measured after withdrawal of VPA, some time after the acute episode.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Magnetic resonance imaging after a one-month interval of lesions of multiple sclerosis in 2 populations, one during an acute attack treated with methylprednisolone, the other stable with no treatment].

Changes in clinical symptoms and MRI lesions of multiple sclerosis (MS) were evaluated on two occasions, one month apart, in 30 patients. Seventeen patients (group 1) with acute exacerbation were treated with methylprednisolone in high, then decreasing doses during a total of 30 days. MRI examinations were performed before and at the end of treatment. The remaining 13 patients (group 2) had been clinically stable for more than 6 months and received no treatment; here again, MRI was performed at 30 days' interval. All patients in group 1 showed functional improvement. The MRI lesions remained stable in 7 of group 1 patients and in 4 of group 2 patients. In the remaining 19 patients (10 in group 1 and 9 in group 2), the number, size and location of MRI lesions were found to have changed over 1 month. There was no correlation between clinical changes and the modification observed at MRI. This study confirms that high-dose corticosteroids are effective, at least clinically, in acute exacerbations, but the main results are that MS is a continually evolving disease, that changes rapidly occur in the lesions observed at MRI and that corticosteroids do not seem to influence the course of MRI lesions. Our study also suggests that MRI is inadequate to evaluate the effectiveness of short-time treatments of MS.

Follow-Up Studies↗
PubMed1990

[Contribution of MRI to the topography of oculomotor disorders in multiple sclerosis].

Magnetic resonance imaging (MRI) was performed in 20 patients with multiple sclerosis and abnormal electro-oculographic examination. All but 2 patients showed MRI abnormalities in the infratentorial region: hypersignal on T2-weighted sequences and/or images of atrophy. Usually, each patient had multiple abnormalities, which could prevent anatomico-oculographic correlations. With oculomotor disorders of cerebellar origin, correlations between clinical findings and MRI images were satisfactory, but with disorders due to brainstem lesions correlations were not so good, as shown by the results in 9 patients with internuclear ophthalmoplegia.

Adult↗
PubMed1989

Multiple sclerosis, sleep latencies and HLA antigens.

The role of HLA antigens, and HLA-DR2 in particular, in the determination of mean sleep onset latencies (MSOLs) in multiple sclerosis (MS) was studied. It has been suggested that this antigen may play a part in the reduction of MSOLs, since nearly 100% of patients suffering from narcolepsy are DR2-positive. A multiple sleep latency test was performed in 37 patients suffering from MS without spontaneous complaints of sleep disturbances and who were typed for HLA-A, B, C, DR and DQ. The MSOL was reduced in a total of 21 patients, in only 7 of 15 DR2-positive patients and in 12 of 21 DQw1-positive patients. However, it was reduced in 13 of 16 B8- or B14-positive patients. In contrast with this, in the absence of an early sleep onset (MSOL greater than 30 min), no HLA antigens were found to be over-represented when considered individually; only those patients positive for a group of cross-reacting HLA antigens (B5, B15, B18, B21 or B35) had an MSOL greater than 30 min. These results suggest that the genes which code for the DR2 or DQw1 antigens, which are present in nearly 100% of narcoleptics, are not solely responsible for the appearance of an early sleep onset in MS.

Adult↗
PubMed1989

Long-acting propranolol in migraine prophylaxis: results of a double-blind, placebo-controlled study.

The efficacy and safety of long-acting propranolol (LA.P), 160 mg once-daily, in the prophylactic treatment of migraine have been tested against placebo in a multicentric, double-blind, randomized study. The two groups are compared in a parallel manner over a treatment period of 12 weeks, following a 4-week placebo run-in period. Fifty-five of the 74 patients who entered the trial were included at the end of the run-in period. Forty-one patients completed the study. None of the 14 patients who withdrew from the study did so because of side effects. The statistical analysis was done according to the "intention to treat" principle. LA.P was significantly more effective than placebo in reducing the frequency of migraine attacks (p = 0.01 by variance analysis). LA.P reduced the average number of monthly crises by 48% on day 84. There was a slight but significant reduction of the systolic blood pressure and heart rate in the erect position, but there was no significant difference between LA.P and placebo regarding either the number of complaints or the number of side effects elicited out of a 17-item questionnaire. None of the observed side effects led to a withdrawal from treatment.

Adult↗