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L Bertrand

Publications and source records attributed to L Bertrand.

14 recordsLinked to original sources
PubMed1991

Cloning and functional characterization of a cocaine-sensitive dopamine transporter.

We report the cloning of a rat cDNA encoding a functional dopamine transporter. This cDNA, derived from an intron-containing gene, encodes a protein of 620 amino acids. Hydropathicity analysis of the protein sequence suggests the presence of 12 putative transmembrane domains. The protein displays considerable identity with transporters for noradrenaline and GABA (64 and 30%, respectively). Transient expression of the cDNA in COS7 cells directs the expression of dopamine uptake activity with appropriate pharmacology and in a sodium-dependent fashion. In situ hybridization reveals that the mRNA for this transporter is expressed in the substantia nigra and ventral tegmental area, regions that contain dopaminergic cell bodies.

Amino Acid Sequence↗
PubMed1991

Cloning, molecular characterization, and chromosomal assignment of a gene encoding a second D1 dopamine receptor subtype: differential expression pattern in rat brain compared with the D1A receptor.

Multiple D1 dopaminergic receptor subtypes have been postulated on the basis of pharmacological, biochemical, and genetic studies. We describe the isolation and characterization of a rat gene encoding a dopamine receptor that is structurally and functionally similar to the D1 dopamine receptor. The coding region, which is intronless, encodes a protein of 475 amino acids (Mr 52,834) with structural features that are consistent with receptors coupled to guanine nucleotide-binding regulatory proteins. The expressed protein binds dopaminergic ligands and mediates stimulation of adenylyl cyclase with pharmacological properties similar to those of the D1 dopamine receptor. The gene encoding the human homologue of this receptor subtype is located to the short arm of chromosome 4 (4p16.3), the same region as the Huntington disease gene. In striking contrast to the previously cloned D1 receptor, little or no mRNA for the receptor described here was observed in striatum, nucleus accumbens, olfactory tubercle, and frontal cortex. High levels of mRNA for this receptor were found in distinct layers of the hippocampus, the mammillary nuclei, and the anterior pretectal nuclei, brain regions that have been shown to exhibit little or no D1 dopamine receptor binding. On the basis of its properties we propose that this dopamine receptor subtype be called D1B.

Amino Acid Sequence↗
PubMed1991

Mouse fetal kidneys in serum-free organ culture: effects of epidermal growth factor and hydrocortisone.

1. The present study was undertaken to determine whether epidermal growth factor (EGF, 100 ng/ml) or hydrocortisone (HC, 10(-8)-10(-5) M) directly influence proliferation and differentiation of mouse fetal kidney maturing in serum-free organ culture. 2. Addition of EGF to the medium significantly stimulated DNA synthesis after 2 and 5 days of culture. Labelled nuclei were mainly localized in the mesenchymal tissue. Protein synthesis remained unchanged. Activities of three hydrolases, markers of brush border differentiation, were reduced. 3. Hydrocortisone (HC), at all concentrations used, significantly inhibited DNA synthesis. Labelled nuclei were distributed in various cell populations of both control and treated explants. Protein synthesis was stimulated by 10(-7) M after 5 days of culture. Hydrolase activities were slightly modified by HC treatment. 4. The present results indicate that EGF stimulates whereas HC decreases proliferation. Both factors have regulatory effects on brush border maturation. 5. Thus, this culture model is a valuable tool for the study of nephrogenesis.

Animals↗
PubMed1978

[Angio-immunoblastic lymphadenopathy].

A report is presented on four cases of angioimmunoblastic lymphadenopathy. In this recently individualized entity, adenomegaly with fever and cutaneous eruption is associated with polyclonal hypergammaglobulinemia and autoimmunization, especially of anti-erythrocytic type. The lymph nodes are homogenized by a lymphoplasmo-immunoblastic granuloma with angiogenesis. The disease could be attributed to hyperplasia of B lymphocytes with a deficit of T cells, which would explain the autoimmunization. It appears in some cases to be triggered by accidents of drug intolerance. Prognosis is poor and the course of the disease is nearly always fatal in the long or short term. It is difficult to ascertain whether prolonged remissions, either spontaneous or therapeutic, can be considered actual cures.

Aged↗
PubMed1978

[Cirrhogenic hepatitis due to perhexiline maleate: general review based upon one new case with ultrastructural study (author's transl)].

The authors describe a case of cirrhogenic hepatitis due to Pexid which was given for 8 months at 400 mg/day for a severe angina pectoris. We find here the anatomo-clinical profile of perhexiline maleate hepatiits already described in approximately 20 cases. There was a cirrhogenic evolution in our case as in 5 others : but here cirrhosis was revealing and seems stabilized since the treatment was stopped. The cirrhogenic evolution could be due to a cumulative effect of the drug and/or to an immuno-allergic mechanism as in alcoholic cirrhosis which is very similar, especially from an anatomical point of view. However cirrhogenic hepatitis differs by a characteristic lysosomal overload : brown pigment under microscopic observation and lipolysosomes with in some cases a lamellar structure under electron microscopic observation. The prescription of such a drug should be limited to cases of refractory angina pectoris and needed a regular clinical and biological survey.

Aged↗
PubMed1977

[Acute alcoholic hepatitis].

Acute alcoholic hepatitis is an anatomical (fatty liver with sclerosing hyaline necrosis) and a clinical (hepatomegaly with a variety of symptoms of hepatic failure) entity arising out of chronic alcoholism, and of a typically 'pre-cirrhotic' state. Although fatal in 25% of acute cases due to failure of homeostasis, it often leaves a centrilobular scarring necrosis which in more than 60% of cases progresses to nodular cirrhosis. Continued alcoholism worsens the prognosis. Alcoholic hepatitis may be confused with acute abdominal catastrophes or with a hepatoma. The characteristic Mallory bodies found on liver biopsy are found rarely in non-alcoholic hepatitis. There is no effective treatment for this disease except reduction of alcohol intake; indeed, the disease may become self-perpetuating.

Acute Disease↗
PubMed1976

Stimulating effect of neutral proteases on cells in vitro.

Some results concerning the stimulatory effect of proteases on lymphocytes and other cells such as Hela cells and fibroblasts are evaluated. Preliminary evidence indicates that such stimulating factors are indeed released from cells during phagocytosis and can be inhibited by aprotinin. The potential role of such proteases in inflammation is discussed.

Animals↗
PubMed1975

[Osteonecrosis, alcoholism and liver steatosis].

Ethylism represents at the present time one of the most frequent etiological factors of primitive osteonecrosis of the femoral head. In relation to a case of osteonecrosis of the femoral head associated with multiple bone infarcts in a chronic alcoholic, also presenting recurring jaundice, alcohol-sensitive hyperlipidaemia, and moderate anaemia, the authors review the role of fatty embolisms in the formation of primitive osteonecrosis of the femoral head. These fatty embolisms may be the result of alcohol-induced hyperlipidaemia, possibly an associated pancreatic disorders, or in particular of hepatic steatosis. A systematic histological study of 10 recent unselected cases of primitive osteonecrosis of the femoral head confirmed the extreme frequency of such embolisms (8 cases out of 10).

Adult↗