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J Besson

Publications and source records attributed to J Besson.

At least 37 records · Page 2Linked to original sources
PubMed1996

The genetic code and cyclic codes.

We proposed previously a cyclic code made of 22 triplets, which we now call the AB code. It is made up of the following chain: AUGGUGCCAUUCAAGACUAUGA. The letters A, U, C, G represent the classical symbols of the (purine and pyrimidine) bases of the genetic code. This chain presents the following features: (1) when it is in cyclic form, it begins with the initiation codon AUG, ends with the termination codon UGA, and it can be read triplet after triplet by choosing 1 and only 1 representative of each synonymy class in the classical degenerate genetic code made of 64 triplets. The chain, therefore, possesses 1 and only 1 codon for each amino-acid; (2) except for the doublet CG, triplets of the chain begin with the 15 other possible doublets of bases (satisfying the "wobble" hypothesis presented by Crick); (3) it corresponds (except for 1 base) to the "loop" part of the CEnothera mitochondrial Gly-tRNA; (4) it can be modified, without loss of the properties (1) and (2), in such a way as to have 15 bases in common with the loop part of other mitochondrial tRNA's considered as primitive, like Ala-, Pro- and Arg-tRNA; (5) it contains the most frequent triplets, but not the most rare ones, appearing in the genome of numerous species; (6) it exhibits a coherent internal structure with respect to the molecular weight of its triplets. This structure, also found in the loop part of mitochondrial tRNA's, contains an excess of AU bases with respect to GC bases. This fact has no explanation in the classical probabilistic model of the tRNA's. Therefore, we propose the cyclic AB code as a primitive genetic structure with the essential coding properties of the present genetic code.

Codon↗
PubMed1995

[Psychiatric studies in the migrant].

The psychiatric investigation of foreign patients are important in the understanding of the mechanisms of exclusion. This is a descriptive study on a population of foreign patients consulting an outpatient psychiatric service. The diagnoses and modes of intake are discussed. The psychiatric examination is then analysed underlining what is useful for the physicians to understand foreign patients. Common problems are reviewed. Prevention is possible through adjustment of the frame towards specialized consultations.

Adult↗
PubMed1994

[Alcoholism: from the molecular to public health].

The current knowledge on the interactions between alcohol and the central nervous system moves very quickly. Moreover the scientific advances follow the three axes of our understanding, biological, psychological and sociological, but this implies some dispersion. The present paper focuses on recent advances in neurobiology of alcoholism and shows new perspectives in pharmacological interventions, with new drugs. In the same time, the psychodynamic and systemic understandings are evoked, in a purpose of integration and of public health policy.

Alcohol Deterrents↗
PubMed1993

Pharmacological approach of the treatment of drinking problems: a critical overview.

Many pharmacological agents have been proposed for the treatment of drinking problems. However, there are many pitfalls in the assessment of the clinical interest of those drugs. In this paper, we propose a new classification of drugs of interest for treating alcohol abuse and related problems. We also review the major clinical studies about those pharmacological agents and discuss, through the studies about serotonergic agents, lithium salts, disulfiram and related compounds, some peculiar aspects of those trials that we think to be important to develop better strategies for the evaluation of pharmacotherapy of alcoholism.

Alcohol Deterrents↗
PubMed1993

Treatment evaluation of alcoholism: non pharmacological interventions.

The approach of alcoholism treatment is most frequently multidisciplinary. Beside pharmacological approaches exist a lot of psychotherapeutic and psycho-social treatments. What are the advances in outcome research in these fields: residential treatments, self-help groups, brief interventions, psychotherapies? What is the current status in psychotherapy research and what is the specificity of psychological interventions for alcoholic patients? In this paper we shall make some clarifications on these questions, and we'll show that we need further research with controlled studies of patient-treatment matching.

Alcoholism↗
PubMed1992

Isolation and characterization of sfp: a gene that functions in the production of the lipopeptide biosurfactant, surfactin, in Bacillus subtilis.

The sfp gene is required for cells of Bacillus subtilis to become producers of the lipopeptide antibiotic surfactin. sfp was isolated and its nucleotide sequence was determined. sfp was expressed in Escherichia coli and its putative product was purified for use in antibody production and in amino acid sequence analysis. The gene was plasmid-amplified in B. subtilis, where it conferred a Srf+ phenotype on sfp0 (surfactin non-producing) cells. Overproduction of Sfp in B. subtilis did not cause production of an increased amount of surfactin and resulted in the repression of a lacZ transcriptional fusion of the srfA operon, which encodes enzymes that catalyze surfactin synthesis. We propose that sfp represents an essential component of peptide synthesis systems and also plays a role, either directly or indirectly, in the regulation of surfactin biosynthesis gene expression.

Amino Acid Sequence↗
PubMed1992

One hundred requests for predictive testing for Huntington's disease.

In Grampian region, the first 100 requests for predictive testing for Huntington's disease have been analysed. Forty-five presymptomatic predictive test results have been given, eleven families have made a decision to undergo prenatal exclusion tests, and so far eleven pregnancies have been investigated using chorion villus biopsy. This paper presents the protocol used and a descriptive analysis of those receiving results, those choosing to leave the programme, and those unable to complete it because of an unsuitable family structure or unco-operative relatives.

Adult↗
PubMed1990

Effect of the antiepileptic drug sodium valproate on glutamine and glutamate metabolism in isolated human kidney tubules.

We studied the effects of sodium valproate, a widely used antiepileptic drug and a hyperammonemic agent, on L-[1-14C]glutamine and L-[1-14C]glutamate metabolism in isolated human kidney-cortex tubules. Valproate markedly stimulated glutamine removal as well as the formation of ammonia, 14CO2, pyruvate, lactate and alanine, but it inhibited glucose synthesis; the increase in ammonia formation was explained by a stimulation by valproate mainly of flux through glutaminase (EC 3.5.1.2) and to a much lesser extent of flux through glutamate dehydrogenase (EC 1.4.1.3). By contrast, valproate did not stimulate glutamate removal or ammonia formation, suggesting that the increase in flux through glutamate dehydrogenase observed with glutamine as substrate was secondary to the increase in flux through glutaminase. Accumulation of pyruvate, alanine and lactate in the presence of valproate was less from glutamate than from glutamine. Inhibition by aminooxyacetate of accumulation of alanine from glutamine caused by valproate did not prevent the acceleration of glutamine utilization and the subsequent stimulation of ammonia formation. It is concluded from these data, which are the first concerning the in vitro metabolism of glutamine and glutamate in human kidney-cortex tubules, that the stimulatory effect of valproate is primarily exerted at the level of glutaminase in human renal cortex.

Adult↗