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A Malafosse

Publications and source records attributed to A Malafosse.

67 records · Page 4Linked to original sources
PubMed1994

Family studies in narcolepsy.

Out of a population of 188 unrelated narcoleptic probands, we identified 14 probands (7.44%) with a family history of narcolepsy, 23 (12.23%) with a family history of isolated repeated episodes of naps and/or lapses into sleep and 151 (80.31%) without a family history of either condition. Clinical, polysomnographic or zygotic differences could not be evidenced in the three groups. Empirical risk for narcolepsy was 40.7 times greater among first-degree relatives of narcoleptics than in the general population. Narcolepsy and the condition characterized by isolated repeated episodes of naps and/or lapses into sleep have a common genetic component. This finding has important implications. Indeed, when the latter condition is included in the spectrum of narcolepsy, the empirical risk figure is relatively close to that expected in cases of simple mode of inheritance. A trend in favor of a more frequent transmission through mothers than fathers is emphasized.

Age of Onset↗
PubMed1993

Electroclinical signs of benign neonatal familial convulsions.

Benign neonatal familial convulsions comprise a distinct epileptic syndrome with an autosomal mode of transmission. The electroclinical signs of seizures in this syndrome are not yet well defined. In 3 children from two families presenting with benign neonatal familial convulsions, 14 seizures were recorded during electroencephalographic (EEG)-video sessions. All seizures occurred during sleep, after a short arousal reaction. Seizures started with bilateral, symmetrical flattening of the EEG for 5 to 19 seconds; simultaneously there was apnea and tonic motor activity. The EEG flattening was followed by a long (1-2-minute) bilateral discharge of spikes and sharp waves; simultaneously, there were vocalizations, chewing, and focal or generalized clonic activity. The prominence of EEG and motor abnormalities varied between the left and the right from one seizure to the next in any given child. The seizures stopped without EEG or clinical postictal depression. These electroclinical observations suggest that the convulsions of benign neonatal familial convulsions are a form of generalized tonic-clonic seizure whose expression may be asymmetrical, probably because of the immaturity of the corpus callosum or other structures ensuring seizure synchronization.

Adult↗
PubMed1992

Identical genetic locus for Baltic and Mediterranean myoclonus.

Genetic linkage analysis shows that Baltic and Mediterranean myoclonus, two forms of progressive myoclonus epilepsy, are closely linked to marker D21S113 on the long arm of chromosome 21. Baltic and Mediterranean myoclonus are most probably due to mutations of the same gene.

Alleles↗
PubMed1992

Confirmation of linkage of benign familial neonatal convulsions to D20S19 and D20S20.

Benign familial neonatal convulsions (BFNC) is an idiopathic form of epilepsy beginning within the first six months of life. Its genetic origin and autosomal dominant mode of inheritance have been suspected since its first description. Recently, the BFNC gene has been localised within chromosome 20q in one large pedigree. For the first time, we confirm here (with D20S19 and D20S20) the close linkage of BFNC to chromosome 20q in six French pedigrees. In addition, the existence in these families of several cases of febrile convulsions (FC), another epileptic syndrome with an autosomal dominant genetic component, led us to study the possibility of a genetic background identical to BFNC. Our results suggest the existence of different susceptibility genes for BFNC and FC.

Blotting, Southern↗
PubMed1992

Failure to replicate linkage between chromosome 5q11-q13 markers and schizophrenia in 28 families.

Sherrington et al. (1988) reported linkage between markers located on the 5q11-q13 region of chromosome 5 and schizophrenia in five Icelandic and two British families. To date, however, all attempts to replicate the initial finding have failed. Using three markers of chromosome 5, we have studied 28 additional French pedigrees. When our data were analyzed both with parametric (i.e., lod scores) and nonparametric methods, we found no evidence of linkage. Thus, we were unable to replicate the earlier report by Sherrington et al.

Chromosomes, Human, Pair 5↗
PubMed1992

Evidence for a pseudoautosomal locus for schizophrenia. II: Replication of a non-random segregation of alleles at the DXYS14 locus.

Because of an association between sexual aneuploidies and schizophrenia, and because schizophrenic siblings have been found to be more often of the same than of the opposite sex, the susceptibility locus for schizophrenia is thought to lie within the pseudoautosomal region of the sex chromosomes. We analysed 33 sibships comprising 18 pairs, 13 trios, and 2 quartets of affected siblings, and found support for non-random segregation of of alleles at the DXYS14 locus in affected siblings. These findings are consistent with the pseudoautosomal hypothesis for schizophrenia and favour a genetic linkage between DXYS14 and the disease.

Alleles↗
PubMed1991

Absence of linkage between chromosome 11p15 markers and manic-depressive illness in a Belgian pedigree.

OBJECTIVE: The original finding of genetic linkage in an Old Order Amish pedigree has been contradicted by the results of several subsequent studies. Using the same genetic parameter values, diagnostic criteria, and 11p15 genetic markers as those used to study the initial Amish population, the authors performed a linkage study of a four-generation informative pedigree in Belgium. METHOD: Recombinant DNA technology was used to analyze three markers for the chromosome 11p15 location: the genes for tyrosine hydroxylase (TH) and insulin (INS) and the c-Harvey-ras oncogene (HRAS). Diagnoses of the relatives of a proband with bipolar affective disorder were determined with the Schedule for Affective Disorders and Schizophrenia--Lifetime Version and based on the Research Diagnostic Criteria. Relatives were considered affected if they had bipolar disorder, unipolar disorder, or cyclothymia; a diagnostic hierarchy was developed to include unipolar disorder and cyclothymia in the linkage analysis. RESULTS: Pairwise analyses of the disease locus and each of the three polymorphisms excluded the possibility of close linkage between manic-depressive illness and the three chromosome 11p15 markers. Multipoint linkage analysis combining the information from all three genes also excluded linkage. CONCLUSIONS: The conflict between the original results from the Amish study and the many negative reports on chromosome 11 linkage of manic-depression has been interpreted as indicating genetic heterogeneity, but heterogeneity has not been documented for the 11p15 locus. Conversely, the linkage approach has major drawbacks, so other genetic strategies should also be considered.

Adolescent↗
PubMed1990

Propagation of improved breeds: the role of artificial insemination and embryo transfer.

Artificial insemination (AI) and embryo transfer (ET) are not just reproductive techniques, but indispensable tools for genetic improvement. In this sense, they play an effective part in propagating improved breeds. Analysis of the development of insemination of French cattle breeds since 1960 shows how breeders can alter their genetic choices to meet economic needs. AI and ET also have their place in selection programmes: evaluating bulls by progeny testing, exerting greater selection pressure on the dams of bulls, and shortening the generation interval of breeding animals. Finally, the income of breeders is closely linked to the genetic level of the livestock which they utilise.

Animals↗
PubMed1986

Facilitation of olfactory bulb kindling after specific destruction of serotoninergic terminals in the olfactory bulb of the rat.

The role of serotonin (5-HT) in the kindling model of epilepsy was investigated by performing specific lesions of the 5-HT innervation at the level of the primary epileptogenic focus. We injected bilaterally 5,6-dihydroxytryptamine in the olfactory bulb (OB) of adult rats which were submitted to electrical stimulations of the OB until the occurrence of stage-5 seizures. Immunohistochemical controls of lesions were realized with a specific anti-5-HT antibody. Results revealed that the lesions facilitated the initial development of kindling (increase of afterdischarge duration and of kindling rate), suggesting that 5-HT terminals exert a modulatory effect on the propagation of the epileptic activity.

Animals↗
PubMedDate not supplied

Benign infantile epilepsy with autosomal dominant inheritance.

Benign cryptogenic infantile epilepsy occurred in 6 infants of 3 families, with similar characteristics suggesting a common physiopathology: onset between 3 and 12 months of age, clusters of brief generalized seizures easily controlled by anti-epileptic drugs, normal psychomotor development, usually normal EEG with, rarely, generalized interictal spike-waves, no recurrence after drug discontinuation, the treatment being no longer than 16 months in most cases. Identical histories were found in parents, uncles and aunts, suggesting an autosomal dominant mode of inheritance. This seems to correspond to an original form of early onset, benign infantile epilepsy.

Age of Onset↗