Attempt of Definition on Dipping Phenomenon

in Journal of Hypertension (Supplement) (1996), 14(1),

EIT: Extreme-Ultraviolet Imaging Telescope for the SOHO Mission

in Solar Physics (1995), 162

The Extreme-ultraviolet Imaging Telescope (EIT) will provide wide-field images of the corona and transition region on the solar disc and up to 1.5 Ro above the solar limb. Its normal incidence multilayer ... [more ▼]

The Extreme-ultraviolet Imaging Telescope (EIT) will provide wide-field images of the corona and transition region on the solar disc and up to 1.5 Ro above the solar limb. Its normal incidence multilayer-coated optics will select spectral emission lines from Fe IX (171 Å), Fe XII (195 Å), Fe XV (284 Å), and He II (304 Å) to provide sensitive temperature diagnostics in the range from 6 × 10[SUP]4[/SUP] K to 3 × 10[SUP]6[/SUP] K. The telescope has a 45 x 45 arcmin field of view and 2.6 arcsec pixels which will provide approximately 5-arcsec spatial resolution. The EIT will probe the coronal plasma on a global scale, as well as the underlying cooler and turbulent atmosphere, providing the basis for comparative analyses with observations from both the ground and other SOHO instruments. This paper presents details of the EIT instrumentation, its performance and operating modes. [less ▲]

La passion du philosophe

in Avancées (1995)

Co-registration and complex interpolation

in Franceschetti, G.; Oliver, C.; Shiue, J. (Eds.) et al Synthetic Aperture Radar and Passive Microwave Sensing (1995, November 25)

This paper presents a novel and efficient method, based on a modified version of the Chirp-Z transform algorithm, for performing the co-registration of SAR images as required in SAR interferometry. The ... [more ▼]

This paper presents a novel and efficient method, based on a modified version of the Chirp-Z transform algorithm, for performing the co-registration of SAR images as required in SAR interferometry. The method also allows complex interpolation of an entire image, by application, at each point of a bilinear coordinate transformation. [less ▲]

Mutations Affecting the Mitochondrial Genes Encoding the Cytochrome Oxidase Subunit I and Apocytochrome B of Chlamydomonas Reinhardtii

in Molecular & General Genetics [=MGG] (1995), 249(2), 179-84

Mitochondrial mutants of the green alga Chlamydomonas reinhardtii that are inactivated in the cytochrome pathway of respiration have previously been isolated. Despite the fact that the alternative oxidase ... [more ▼]

Mitochondrial mutants of the green alga Chlamydomonas reinhardtii that are inactivated in the cytochrome pathway of respiration have previously been isolated. Despite the fact that the alternative oxidase pathway is still active the mutants have lost the capacity to grow heterotrophically (dark + acetate) and display reduced growth under mixotrophic conditions (light + acetate). In crosses between wild-type and mutant cells, the meiotic progeny only inherit the character transmitted by the mt- parent, which indicates that the mutations are located in the 15.8 kb linear mitochondrial genome. Two new mutants (dum-18 and dum-19) have now been isolated and characterized genetically, biochemically and at the molecular level. In addition, two previously isolated mutants (dum-11 and dum-15) were characterized in more detail. dum-11 contains two types of deleted mitochondrial DNA molecules: 15.1 kb monomers lacking the subterminal part of the genome, downstream of codon 147 of the apocytochrome b (COB) gene, and dimers resulting from head-to-head fusion of asymmetrically deleted monomers (15.1 and 9.5 kb DNA molecules, respectively). As in the wild type, the three other mutants contain only 15.8 kb mitochondrial DNA molecules. dum-15 is mutated at codon 140 of the COB gene, a serine (TCT) being changed into a tyrosine (TAC). dum-18 and dum-19 both inactivate cytochrome c oxidase, as a result of frameshift mutations (addition or deletion of 1 bp) at codons 145 and 152, respectively, of the COX1 gene encoding subunit I of cytochrome c oxidase. In a total of ten respiratory deficient mitochondrial mutants characterized thus far, only mutations located in COB or COX1 have been isolated.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

Factors influencing the immediate and late outcome of cushing-disease treated by transsphenoidal surgery : A retrospective study by the european cushings-disease survey group

in Journal of Clinical Endocrinology and Metabolism (1995), 80(11), 3114-3120

Hypercortisolism attributable to hypersecretion of ACTH by a pituitary adenoma is an uncommon and progressively lethal disease. Because of its rarity, it has been difficult to collect a large series of ... [more ▼]

Hypercortisolism attributable to hypersecretion of ACTH by a pituitary adenoma is an uncommon and progressively lethal disease. Because of its rarity, it has been difficult to collect a large series of patients in order to identify the prognostic factors influencing the outcome after transsphenoidal surgery. We conducted a multicenter, retrospective analysis of the early and late results of surgical treatment of Cushing's disease. Files of patients with Cushing's disease who underwent transsphenoidal surgery between 1975 and 1990 were collected from 25 institutions throughout Europe. Data from 668 of 716 patients were suitable for statistical analyses. Surgical mortality was 1.9%, and major morbidity occurred in 97 patients (14.5%). Clinical and biochemical remission of Cushing's disease after surgery occurred in 510 cases (76.3%). Identification of the tumor by neuroradiological imaging or at operation with histopathological corroboration was associated with remission of hypercortisolism. Recurrence of the disease occurred in 65 (12.7%) of 510 patients in remission after surgery at a mean time of 39.3 months (range 6-104 months). The distribution of the recurrences did not show any apparent plateau or cluster throughout the follow-up period. Low postoperative steroid levels, absence of cortisol response to CRH, and the need for long-term glucocorticoid substitution therapy were all associated with a high probability of long-term remission. Our study demonstrates that transsphenoidal surgery is a safe and effective treatment for patients with Cushing's disease. However, after successful surgery there is a steady increase in the percentage of recurrences, which continues with time. Patients who after operation had hypoadrenocorticism and needed long-term glucocorticoid substitution therapy had the lowest risk of relapse. [less ▲]

Procédures d'évaluation adaptées à de grands groupes d'étudiants universitaires : enjeux et solutions pratiquées à la FAPSE-ULg

(1995, November)

The prevalence of colonic polyps in acromegaly : a prospective colonoscopic and pathological study in 103 patients.

in Journal of Clinical Endocrinology and Metabolism (1995), 80(11), 3223-3226

Patients with acromegaly are reported to be at risk of developing adenomatous colonic polyps, which are considered to be preneoplastic lesions. This assumption is, however, usually drawn from results ... [more ▼]

Patients with acromegaly are reported to be at risk of developing adenomatous colonic polyps, which are considered to be preneoplastic lesions. This assumption is, however, usually drawn from results obtained in rather small series of patients or without a control group. We, therefore, undertook a prospective colonoscopic and pathological study comprising 103 acromegalic patients and 138 nonacromegalic control subjects referred for irritable bowel syndrome. The prevalence of adenomatous colonic polyps was significantly increased in acromegalic patients compared to that in control subjects (22.3% vs. 8.0%; P = 0.0024). The significance was similarly present in male acromegalic patients (28.6% vs. 5.5% in male control subjects; P = 0.0026), but was absent in female acromegalic patients. The prevalence of colonic polyps was also significantly increased in the group of acromegalic patients under 55 yr of age (20.0% vs. 3.0% in the control group of the same age; P = 0.0026). Other characteristics of adenomatous colonic polyps in acromegaly were the multiplicity and the presence proximal to the splenic flexure. No difference in the duration of acromegaly was found between patients with or without adenomatous polyps. The prevalence of hyperplastic colonic polyps was also significantly increased to 24.3% in acromegalic patients vs 4.4% in control subjects (P < 0.001). In conclusion, in view of the increased incidence of adenomatous colonic polyps, colonoscopy should be part of the follow-up examination in acromegaly. [less ▲]

Retinoic Acid Induces Three Newly Cloned Hoxa1 Transcripts in Mcf7 Breast Cancer Cells

in Biochemical and Biophysical Research Communications (1995), 215(2), 713-20

Coordinated expression of genes involved in development, differentiation and malignant transformation is regulated by transcription factors including homeodomain-containing proteins. However, most of ... [more ▼]

Coordinated expression of genes involved in development, differentiation and malignant transformation is regulated by transcription factors including homeodomain-containing proteins. However, most of their cDNA sequences are still unknown. We report here the molecular characterization of three newly cloned HOXA1 transcripts from human breast cancer cells. In addition, we provide evidence that these alternatively spliced transcripts encode one homeodomain-containing protein and two products lacking the conserved DNA-binding domain. Moreover, we demonstrate that all three HOXA1 transcripts are induced by retinoic acid in MCF7 cells. Taken together, our results suggest that HOXA1 gene may be a key element in the establishment of the breast cancer cell phenotype. [less ▲]

Tentative definition of dipping phenomenom

Conference (1995, October 07)