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G Lenoir

Publications and source records attributed to G Lenoir.

At least 91 records · Page 5Linked to original sources
PubMed1995

[Infectious complication after lung transplantation for cystic fibrosis].

The infectious complications after lung transplantation have been studied in 26 patients suffering from mucoviscidosis who had transplants in the Ile-de-France between July 1987 and October 1990. We counted 99 infections (74 bacterial infections, 23 viral infections and two fungal infections) during a cumulative observation period of 127 months. The majority of the infections (48%) were localised to the grafted lung. These infections were responsible for 61% of deaths (50% secondary to bacterial infections and 11% to viral infections). The risk of infection remains even after a considerable time after transplantation in this series. These studies underline the importance of infectious complications in the mortality and morbidity of lung transplant patients suffering from mucoviscidosis.

Adolescent↗
PubMed1995

Endoscopic and CT-scan evaluation of rhinosinusitis in cystic fibrosis.

In order to obtain an accurate evaluation of nasal and paranasal sinus disease in cystic fibrosis patients, 75 patients with a proven cystic fibrosis diagnosis have been investigated using the following standard techniques: questionnaire, ENT examination, endoscopical examination, sinus X-rays, and in 31% of the cases a CT scan. The analysis of results shows that nasal obstruction is the most frequent symptom (32%) and that nasal polyps are present in 43% of the cases. Endoscopic examination seems to be of great interest in giving a more accurate picture of nasal and paranasal sinus disease. Analysis of CT scan images leads the authors to describe a new and specific entity in nasal and paranasal sinus disease in cystic fibrosis patients: the pseudomucocele. In this report, the authors discuss the various aspects of pseudomucocele, attaching particular importance to the CT scan results.

Adolescent↗
PubMed1994

Cytogenetic and molecular analysis of 6q deletions in Burkitt's lymphoma cell lines.

Although abnormalities of chromosome 6 have frequently been observed in Burkitt's lymphoma (BL), they have so far not been defined by modern cytogenetic and molecular methods. By a combination of high-resolution chromosome banding, fluorescence in situ hybridization (FISH), and loss of heterozygosity (LOH) analysis, we have examined the nature of aberrations affecting chromosome 6 in 7 previously established BL cell lines. All cell lines exhibited the characteristic translocations associated with BL; 5 had t(8;14)(q24;q32) and 2 had t(8;22)(q24;q11). Three cell lines had deletions of 6q; 3 others had rearrangements affecting 6q, whereas one cell line had apparently normal chromosomes 6. FISH analysis of the three deletions established that they were interstitial. LOH analysis with probes mapped to the 6q26-27 region confirmed the sub-telomeric interstitial deletion in cell line BL-108, which had a del(6)(q23q27). All informative loci mapped to 6q26-27 (5/7) were deleted in BL-74, which had no apparent cytogenetic abnormality in chromosome 6, thus documenting a sub-microscopic deletion. These data define the cytogenetic and molecular limits of 6q deletions in BL and are consistent with our previous demonstration of LOH analysis of the site of a candidate tumor suppressor gene in the 6q25-27 region.

Adolescent↗
PubMed1994

The gene for hereditary breast-ovarian cancer, BRCA1, maps distal to EDH17B2 in chromosome region 17q12-q21.

A gene for hereditary breast and ovarian cancer, BRCA1, has been mapped to chromosome 17q12-q21. This gene is responsible for cancer susceptibility in the majority of families with multiple cases of ovarian cancer and early-onset breast cancer. We report linkage results of a family with 10 cases of breast cancer and a single case of ovarian cancer. A recombinant event in this family places BRCA1 distal (telomeric) to the locus EDH17B2, which codes for the enzyme estradiol 17 beta-dehydrogenase II. This recombinant is based on the appearance of breast cancer in a 45 year old woman. Under our genetic model, we estimate the probability that this woman carries a BRCA1 mutation to be 94%. These data further reduce the region of assignment of BRCA1 on chromosome 17q12-q21 and should expedite positional cloning of this important gene.

Adult↗
PubMed1994

Insulin responses to intravenous glucose and the hyperglycemic clamp in cystic fibrosis patients with different degrees of glucose tolerance.

The relationship between altered insulin secretion and impaired glucose tolerance was studied in 32 cystic fibrosis patients, 16 men and 16 women, aged 8-26 y, using oral and i.v. glucose tolerance tests and a hyperglycemic glucose clamp (10 mmol/L). Seven of these subjects were already being treated with insulin; seven had fasting blood glucose levels below 7.2 mmol/L but satisfied diabetic criteria at the oral glucose tolerance test; glucose tolerance was impaired in 13 subjects and normal in five. The insulin responses to the two i.v. glucose stimuli were inversely correlated with the plasma glucose levels (60 and 120 min) and the area under the curve of the oral glucose tolerance test. However, the acute insulin response to i.v. glucose was severely altered in patients with impaired glucose tolerance, whereas plasma insulin levels during the hyperglycemic clamp did not differ from those of healthy subjects. The responses to the two stimuli were dramatically low in the diabetic patients. These results suggest that cystic fibrosis patients with normal or impaired glucose tolerance retain their capacity to secrete insulin. Alterations in the acute phase of glucose-stimulated insulin secretion seem to be principally responsible for the early impairment in glucose tolerance.

Administration, Oral↗
PubMed1994

Germ-line exclusion of a single p53 allele by premature termination of translation in a Li-Fraumeni syndrome family.

Germline p53 mutations have been detected in approximately half of the families affected by the Li-Fraumeni syndrome (LFS), in which they are believed to represent the genetic status predisposing to multiple cancers. Failure to detect mutations in the other half of LFS families suggests that sequence analysis, which has been limited to the p53 gene coding region, have overlooked other genetic events lying outside of this region or/and that alterations in other gene(s) than p53 may also lead to the syndrome. In this report, we present the evidence that a single base pair deletion in the p53 coding sequence, leading to premature signal termination of translation, generates a null allele by preventing transport of mutant allele mRNAs into the cytoplasm. This allelic exclusion which confers a status of unizygote vis-à-vis the wild-type p53 gene to individuals who carry the mutant allele, leads to predisposition to multiple cancers in a Li-Fraumeni family. Thus, the loss of the wild-type p53 allele appears as the rate limiting step in tumor induction.

Alleles↗
PubMed1993

Serum interleukin-10 in non-Hodgkin's lymphoma: a prognostic factor.

Serum interleukin-10 (IL-10) was measured retrospectively in 153 patients with a fully documented history of non-Hodgkin's lymphoma (NHL) using an enzyme-linked immunosorbent assay (ELISA) detecting both human IL-10 and the Epstein-Barr virus (EBV) molecule BCRF1/viral IL-10. IL-10 was detectable in 47 (46%) of the 101 patients with active NHL, 3 of 52 (6%) patients in first partial or complete response, and none of the 60 healthy blood donors. Serum IL-10 was detectable with a similar frequency in all subtypes of NHL and in all clinical stages, as well as in EBV-seropositive and EBV-negative patients. In patients with intermediate or high-grade NHL, the presence of detectable serum IL-10 at diagnosis was correlated to a significantly shorter overall (P = .025) and progression-free (P = .030) survival. Patients with stage IV disease and detectable serum IL-10 had a particularly poor prognosis (4 years of survival: 0%). Multivariate analysis showed that IL-10 was an independent prognosis factor. These results indicate that IL-10 is detectable in a subgroup of patients with active NHL and correlates to a poor survival in patients with intermediate or high-grade NHL.

Adolescent↗
PubMed1993

DNA screening for breast/ovarian cancer susceptibility based on linked markers. A family study.

BACKGROUND: Linkage to chromosome 17q has been identified in hereditary breast cancer and hereditary breast/ovarian cancer syndrome. A hereditary breast/ovarian cancer syndrome kindred was identified that yielded a highly significant lod score (4.20) when 17q markers were studied, enabling us to identify those who probably carried the cancer-associated gene among the high-risk members of the family. METHODS: High-risk members of the hereditary breast/ovarian cancer syndrome kindred were offered counselling on the basis of 17q markers. Family members responding positively received one-to-one genetic counseling in a structured setting. Subjects were educated before disclosure, and the immediate impact of this information was assessed after disclosure. RESULTS: We provided genetic counseling on the basis of linkage findings to 32 relatives (four men and 28 women). Women who were told they were linkage positive expressed an increased motivation for surveillance and prophylactic surgery. Most women who were told they were linkage negative indicated that they would not proceed with prophylactic surgery but would continue careful surveillance. To date, there has been no evidence of serious emotional disturbances resulting from this disclosure. We believe that this experience can be used by cancer geneticists and physicians in developing protocols for genetic counseling in cancer-associated hereditary disorders. CONCLUSIONS: Physicians must understand current developments in cancer genetics and linkage so that they can be applied to genetic counseling and treatment of high-risk patients.

Adult↗
PubMed1993

Routine prostaglandin assay by GC-MS in multiwell tissue culture plates: application to human synoviocytes and chondrocytes.

Prostanoids can be assayed by the highly sensitive and reproducible gas chromatography-negative ion chemical ionization-mass spectrometry (GC-NICI-MS) technique. This paper describes a simplified method applied to the quantification of prostaglandins (PG) in the supernatants of limited amounts of cells, cultured in multiwell plates (30,000 cells/well). The culture medium was extracted on C2 columns and the derivatization was performed in three steps. Prostanoids were then analyzed by GC-NICI-MS within 10 min. The storage conditions at each step were tested in order to achieve maximal yields. This procedure allowed the determination and quantification of PG produced by cultured human synovial cells and chondrocytes at the basal level as well as after interleukin-1 stimulation. PGE2, PGF2 alpha, and 6-keto-PGF1 alpha, the stable form of PGI2, were the main PG detected. Derivatization and GC-MS analyses of 18 samples could easily be performed in 1 day. The simplified GC-NICI-MS method can thus be routinely applied for assaying PG in any cell line cultured in multiwells.

Calibration↗
PubMed1993

The human insulin-like growth factor-binding protein 4 gene maps to chromosome region 17q12-q21.1 and is close to the gene for hereditary breast-ovarian cancer.

The gene for insulin-like growth factor-binding protein 4 (IGFBP4) codes for a serum protein that binds to the family of insulin-like growth factors and modulates their activity. It has been mapped by in situ hybridization to chromosome region 17q12-q21.1. We have developed a CA-repeat polymorphism from a cosmid clone containing IGFBP4. By linkage analysis, IGFBP4 maps to the chromosome 17q interval THRA1-D17S579. This interval also contains the gene for hereditary breast-ovarian cancer, BRCA1. Genetic recombination between IGFBP4 and BRCA1 places IGFBP4 centromeric to the cancer susceptibility gene and effectively excludes it as a candidate gene for BRCA1. IGFBP4 is, however, one of the closest known centromeric markers for BRCA1; the estimated recombination fraction is 0.015. IGFBP4 and D17S579 together define a 2.8-cM interval that contains BRCA1.

Base Sequence↗
PubMed1993

Genetic mapping of the breast-ovarian cancer syndrome to a small interval on chromosome 17q12-21: exclusion of candidate genes EDH17B2 and RARA.

A susceptibility gene for hereditary breast-ovarian cancer, BRCA1, has been assigned by linkage analysis to chromosome 17q21. Candidate genes in this region include EDH17B2, which encodes estradiol 17 beta-hydroxysteroid dehydrogenase II (17 beta-HSD II), and RARA, the gene for retinoic acid receptor alpha. We have typed 22 breast and breast-ovarian cancer families with eight polymorphisms from the chromosome 17q12-21 region, including two in the EDH17B2 gene. Genetic recombination with the breast cancer trait excludes RARA from further consideration as a candidate gene for BRCA1. Both BRCA1 and EDH17B2 map to a 6 cM interval (between THRA1 and D17S579) and no recombination was observed between the two genes. However, direct sequencing of overlapping PCR products containing the entire EDH17B2 gene in four unrelated affected women did not uncover any sequence variation, other than previously described polymorphisms. Mutations in the EDH17B2 gene, therefore do not appear to be responsible for the hereditary breast-ovarian cancer syndrome. Single meiotic crossovers in affected women suggest that BRCA1 is flanked by the loci RARA and D17S78.

17-Hydroxysteroid Dehydrogenases↗