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F Rey

Publications and source records attributed to F Rey.

At least 73 records · Page 4Linked to original sources
PubMed1992

Time and space clusters of the French-Canadian M1V phenylketonuria mutation in France.

We performed mutation analysis and RFLP haplotype analysis of chromosomes associated with classical phenylketonuria (PKU) in contemporary French families. We also did genealogical reconstructions for seven obligate carriers in five contemporary French-Canadian families living in eastern Quebec, who carry the M1V mutation causing PKU. The M1V mutation, heretofore considered to be associated exclusively with French-Canadians, was found on 4 of 152 independent French chromosomes. The French and Quebec M1V mutations all occurred on RFLP haplotype 2. The contemporary mutant French chromosomes clustered in southern Brittany (Finistère Sud). Genealogical reconstructions of the Quebec families identified 53 shared ancestors and a center of diffusion in the Perche region in 17th century France. The two clusters in France, one historical and the other contemporary, are not incompatible, if one assumes the possibilities that settlers returned from Nouvelle France or moved from Perche to southern Brittany. The M1V mutation is serving as a useful marker for historical demography.

Base Sequence↗
PubMed1991

A 3-base pair in-frame deletion of the phenylalanine hydroxylase gene results in a kinetic variant of phenylketonuria.

Phenylketonuria (PKU) is an autosomal recessive disease due to deficiency of a hepatic enzyme, phenylalanine hydroxylase (PAH). The absence of PAH activity results in typical PKU while persistence of a residual enzyme activity gives rise to variant forms of the disease. We report here a 3-base pair in-frame deletion of the PAH gene (delta 194) in a mild variant, with markedly reduced affinity of the enzyme for phenylalanine (Km = 160 nM), and we provide functional evidence for responsibility of the deletion in the mutant phenotype. Since the deletion was located in the third exon of the gene, which presents no homology with other hydroxylases, we suggest that exon 3 is involved in the specificity of the enzyme for phenylalanine. Finally, since none of the 98 PKU patients tested were found to carry this particular deletion, our study suggests that this molecular event probably occurred recently on the background of a haplotype 2 gene in Portugal.

Base Composition↗
PubMed1991

[Test with ovine corticotropin-releasing hormone (oCRH): clinical application and reference values in the young adult and the postmenopausal women].

CRH (corticotropin-releasing hormone) is a hypothalamic polypeptide that stimulates ACTH secretion by the anterior pituitary and, subsequently, cortisol secretion by the adrenal cortex. CRH test administration is indicated in the differential diagnosis of Cushing syndrome and in the assessment of corticotropic function in different pituitary conditions. Both human CRH (hCRH) and ovine CRH (oCRH) can be used by i.v. injection. Intrinsic ACTH-releasing activities of the two molecular forms are similar. Nevertheless, and contrary to hCRH, oCRH does not interact with the human CRH specific binding protein (CRH-BP) and the use of this ovine form could be useful in testing pituitary function while avoiding possible changes in peptide activity due to protein binding. The present study was conducted in 3 distinct groups of human volunteers to evaluated the ACTH and cortisol responses to i.v. oCRH (1 micrograms per kg body weight) at noon (oCRH test). 24 healthy, nonobese subjects, not under medication, participated in the study. The first group consisted of 8 young men, the second of 8 women of childbearing age and the third of 8 menopausal women. Tolerance to the oCRH test was excellent in all 3 groups. A significant increase in plasma ACTH and cortisol was observed in all the subjects, with peak occurrence for ACTH between 15 and 60 minutes after oCRH and between 20 and 120 minutes for cortisol. The responses were not sex-related among the young subjects, but the menopausal women displayed a higher cortisol increase than the other 2 groups.

Adrenocorticotropic Hormone↗
PubMed1991

Spectrum of phenylketonuria mutations in western Europe and north Africa, and their relation to polymorphic DNA haplotypes at the phenylalanine hydroxylase locus.

A total of 252 chromosomes from 126 patients with phenylalanine hydroxylase (PAH) deficiencies were analyzed for both mutant genotypes and restriction fragment length polymorphism (RFLP) haplotypes at the PAH locus. The mutant genes studied originated either from Western Europe (116 alleles) or from Mediterranean countries (136 alleles). Only 27% of all mutant alleles were found to carry identified mutations, particularly mutations at codon 252 (2.3%), 261 (7.5%), 280 (6.3%), 408 (3.5%) and at the splice donor site of intron 12 (6.3%). The mutant genotypes were associated with RFLP haplotypes 7, 1, 38, 2 and 3 at the PAH locus respectively. Except for the splice mutation of intron 12, these associations were preferential, but not exclusive, since the other four mutations were found on the background of at least two RFLP haplotypes. These results, together with the observation that 85% of PAH deficient patients are heterozygotes for their mutant genotypes, emphasize the great heterogeneity of PAH deficiencies in Mediterranean countries and hamper systematic DNA testing for carrier status in this population.

Africa, Northern↗
PubMed1991

Dissociated recovery of cortisol and dehydroepiandrosterone sulphate after treatment for Cushing's syndrome.

We have studied the variation of ACTH, cortisol and DHEA-S plasma levels in 6 patients before and up to 15 months after surgical remission of Cushing's syndrome in order to compare the relative dependency of cortisol and adrenal androgens towards ACTH. Three patients with adrenal adenoma were treated by unilateral adrenalectomy. Three other patients with Cushing's disease underwent transsphenoidal pituitary tumorectomy. Preoperative ACTH was undetectable in patients with adrenal adenoma and high-normal or elevated in patients with Cushing's disease. All patients became rapidly hypocortisolemic after surgery and ACTH and cortisol levels eventually recovered at different intervals. Patients with adrenal adenoma had an initially low DHEA-S which failed to normalize for the entire follow-up period. Patients with Cushing's disease had normal or high-normal DHEA-S which became low immediately after surgery, following ACTH decrease, and it remained low during the entire follow-up period. In conclusion, after removal of corticotropic inhibition secondary to excess cortisol, DHEA-S remains suppressed for a longer period of time than cortisol. Moreover it only takes a short period of relatively low ACTH (after pituitary tumor excision) to induce a long lasting DHEA-S inhibition. Therefore the DHEA-S secreting adrenal cells seem to be more sensitive to the lack of corticotropic stimulation than cortisol secreting cells.

Adrenal Gland Neoplasms↗
PubMed1991

CV 205-502 treatment of macroprolactinomas.

CV 205-502, a benzoquinoline, is a new nonergot dopamine agonist compound which has been shown to be effective in lowering PRL levels in normal volunteers and in hyperprolactinemic women. Seven patients (4 men and 3 women) presenting with hyperprolactinemia due to macroprolactinoma were treated with CV 205-502 given as a single daily dose at bedtime for up to 12 months. Six patients presented with impaired gonadal function and 2 with galactorrhea. All patients but one had previously been treated with bromocriptine and 4 had undergone pituitary surgery (3 with complementary radiotherapy). Six patients responded within a few weeks to CV 205-502 treatment, PRL levels being normalized (4 patients, 0.075 to 0.150 mg/day) or significantly reduced to restore normal gonadal function (2 patients, 0.225 mg/day). The seventh patient, who had previously been resistant to bromocriptine, also failed to respond to CV 205-502 treatment even after high doses (0.450 mg/day). Under CV 205-502 treatment, follow-up with magnetic resonance imaging revealed a reduction in tumor size of up to 52% of the initial volume in the "PRL-responders" whereas an increase in tumor size was observed in the "nonresponding" patient. No biological disturbance appeared during CV 205-502 treatment and the drug tolerance was very good, with mild side-effects being reported by only 2 patients. In conclusion, CV 205-502, given once daily, appears to be a safe and effective alternative to other dopamine agonists in the treatment of macroprolactinoma, by reducing hyperprolactinemia and tumor size. It was, however, of no benefit in the one patient whose macroprolactinoma had been resistant to bromocriptine.

Adult↗
PubMed1991

Productive infection of CD4+ cells by selected HIV strains is not inhibited by anti-CD4 monoclonal antibodies.

Differential susceptibility of four diverse HIV strains to inhibition of infection of CD4+ CEM cells by anti-CD4 monoclonal antibodies was studied. The highly cytopathic HIV-1 246 and NDK strains were able to infect CEM cells and undergo several cycles of replication at saturating doses of LEU3-A, OKT4-A, and 13B8-2 monoclonal antibodies, whereas propagation of reference HIV-1 BRU and weakly cytopathic strain HIV-1 PAS was inhibited. Postadsorption treatment by anti-CD4 antibodies had stronger inhibitory effect than did treatment during the virus adsorption period. In parallel experiments, the same monoclonal antibodies successfully blocked syncytium formation between uninfected MT4 cells and CEM cells infected by all four HIV-1 virus strains tested. To explain these seemingly contradictory data we have postulated that anti-CD4 antibodies efficiently inhibit cell-to-cell but not virus-to-cell infection.

Antibodies, Monoclonal↗
PubMed1991

The flavivirus envelope protein E: isolation of a soluble form from tick-borne encephalitis virus and its crystallization.

By the use of limited trypsin digestion of purified virions, we generated a membrane anchor-free and crystallizable form of the tick-borne encephalitis virus envelope glycoprotein E. It retained its reactivity with a panel of monoclonal antibodies, and only subtle structural differences from the native protein E were recognized. Treatment with the bifunctional cross-linker dimethylsuberimidate resulted in the formation of a dimer. Crystallization experiments yielded hexagonal rod-shaped crystals suitable for X-ray diffraction analysis.

Amino Acid Sequence↗
PubMed1991

Two distinct mutations at a single BamHI site in phenylketonuria.

Classical phenylketonuria is an autosomal recessive disease caused by a deficiency of hepatic phenylalanine hydroxylase (PAH). The abolition of an invariant BamHI site located in the coding sequence of the PAH gene (exon 7) led to the recognition of two new point mutations at codon 272 and 273 (272gly----stop and 273ser----phe, respectively). Both mutations were detected in north eastern France or Belgium and occurred on the background of RFLP haplotype 7 alleles. The present study supports the view that the clinical heterogeneity in PKU is accounted for by the large variety of mutant genotypes associated with PAH deficiencies.

Base Sequence↗
PubMed1991

Glycosaminoglycans, albuminuria and hydrocarbon exposure.

The value of the glycosaminoglycans (GAG) determination in urine was examined in a population of hydrocarbon-exposed workers and compared to the usefulness of the fractional albumin clearance (FAC). Blood pressure and hydrocarbon exposure interact to increase the FAC but the GAG concentration seems less useful because too many other variables influence it as well.

Adolescent↗
PubMed1991

Single-strand conformation polymorphism for detection of mutations and base substitutions in phenylketonuria.

In the past few years, more than 20 different mutations have been reported in hyperphenylalaninemias. In southwestern Europe and Mediterranean countries, however, the mutant genotypes reported account for only a fraction (27%) of all mutant alleles at the phenylalanine hydroxylase (PAH) locus, and most of the mutations causing the disease remain unknown. In order to develop a strategy for rapid detection of mutation-containing exons, we applied the single-strand conformation-polymorphism (SSCP) technique to exons 3, 5, 7, and 12 of the PAH gene. We observed five abnormal patterns of migration in mutant PAH genes, and we consistently found base substitutions in the corresponding exons, with no false-positive results. By this procedure, two novel putative mutations were detected in the seventh exon of the PAH gene, (A259V and Y277D) and we were able to demonstrate that the delta I94, R158Q, R408W, and E280K mutations were easily detectable by the SSCP technique. This procedure is therefore of particular interest for rapid detection of mutation-containing exons and for determination of further genotype-phenotype correlations in hyperphenylalaninemias.

Base Sequence↗
PubMed1990

Free testosterone levels in plasma and saliva as determined by a direct solid-phase radioimmunoassay: a critical evaluation.

We compared unbound (free) testosterone radioimmunoassay concentrations in plasma and saliva from men, using a direct radioimmunoassay kit involving a ligand analog of testosterone as tracer. The assay failed to reveal detectable testosterone concentrations in saliva. In plasma the free testosterone levels were about 4 times lower than those obtained by calculation or ultrafiltration methods. Moreover, unexpected similar free testosterone levels were obtained in samples comparable in their total testosterone content but distinct in their steroid binding protein content (buffered testosterone dilutions). We suspect that free testosterone levels determined with this direct radioimmunoassay probably do not reflect the true free testosterone values and conclude that their significance remains to be established.

Adult↗
PubMed1990

[Epidemiology and etiology of mesothelioma].

The early diagnosis of mesothelioma rests on very common clinical evidence, including pleuritis of recent onset, history of contact with asbestos chest pain, often moderate loss of weight and slight changes in old pleural images. The sensitivity of formal diagnostic examinations is 23 p. 100 for pleural fluid cytology, 24 p. 100 Adams' needle biopsy and 93 p. 100 for thoracoscopy, where the only negative results are obtained in patients with adhesive pleuritis. Prognosis depends on several factors, the most favourable ones being the histological type of the lesion (epithelial or mixed), the fact that it is limited to the parietal or diaphragmatic pleura and, on the patient's side and accessorily: female sex, lack of exposure to asbestos, age under 50, good general condition and absence of chest pain.

Asbestos↗
PubMed1990

[Diagnosis and prognosis of malignant mesothelioma].

The early diagnosis of mesothelioma rests on very common clinical evidence, including pleuritis of recent onset, history of contact with asbestos, chest pain, often moderate loss of weight and slight changes in old pleural fluid cytology, 24% for Adams' needle biopsy and 93% for thoracoscopy, where the only negative results are obtained in patients with adhesive pleuritis. Prognosis depends on several factors, the most favourable ones being the histological type of the lesion (epithelial or mixed), the fact that it is limited to the parietal or diaphragmatic pleural and, on the patient's side and accessorily: female sex, lack of exposure to asbestos, age under 50, good general condition and absence of chest pain.

Adult↗
PubMed1990

[Glomerular erythrocytes, albuminuria, glycosaminoglycans and exposure to hydrocarbons].

As part of a study on the possible nephrotoxicity of hydrocarbons, the urinary erythrocyte concentration and the percentage of glomerular erythrocytes were assessed. Albumin excretion rate, glycosaminoglycan and retinol-binding protein concentration, and N-acetyl-beta-glucosaminidase activity were measured simultaneously. The results show that the erythrocyte concentration and the percentage of glomerular erythrocytes tend to increase with hydrocarbon exposure, and that a nephrotoxic effect of occupational hydrocarbon exposure deserves consideration.

Acetylglucosaminidase↗
PubMed1990

Emotional effects of physical or mental injury on Hispanic people living in the U.S.A. as adjudged from the content of their speech.

Twenty Hispanic patients, who sustained a work-related physical injury or emotional stress, were compared with 20 Hispanic control subjects, who had not experienced such a recent injurious event, with regard to their anxiety and hostility scores derived from the content analysis of 5-minute speech samples using the Gottschalk-Gleser scales. The patient group had significantly elevated total anxiety scores compared to the control group.

Accidents, Occupational↗
PubMed1990

Hydrocarbon exposure, hypertension and kidney function tests.

Control and hydrocarbon exposed workers participated in a cross-sectional study about the nephrotoxicity of chronic hydrocarbon exposure. Different markers of glomerular and tubular function as well as the celluria were examined and compared. The results show that the interaction between hypertension and hydrocarbon exposure has an influence on the kidney function. For the clearance the interaction age-exposure seems to play a more important role than age or exposure alone. The most useful markers appear to be the albuminuria, the N-acetyl-beta-D-glucosaminidase activity, the retinol-binding-protein concentration and the creatinine clearance.

Adult↗