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D Legrand

Publications and source records attributed to D Legrand.

54 records · Page 3Linked to original sources
PubMed1987

Identification of a major 72 kilodalton surface antigen in twelve isolates of Leishmania braziliensis braziliensis.

The study of the surface antigens of Leishmania braziliensis braziliensis revealed a great homogeneity among ten strains isolated from Bolivia and two reference strains from Brazil and Belize. A 72 kDa major protein, present in all L. b. braziliensis strains, was recognized by both cutaneous and mucocutaneous human sera, but was not recognized by Kala-azar and chagasic sera. No cross-reactive antigens were found among strains of Leishmania braziliensis guyanensis, Leishmania braziliensis panamensis, Leishmania mexicana amazonensis and Leishmania donovani chagasi testing these strains with hamster and human anti-L. b. braziliensis sera. Moreover, these strains possessed major antigens with molecular weights different from those of L. b. braziliensis strains. A microheterogeneity of L. b. braziliensis surface antigens was detected for the high molecular weight antigens and seemed to be related to the isoenzymic microheterogeneity.

Animals↗
PubMed1986

Evidence for interactions between the 30 kDa N- and 50 kDa C-terminal tryptic fragments of human lactotransferrin.

Gel filtration of a mild tryptic digest of diferric human lactotransferrin carried out in presence of 10% (v/v) acetic acid led to the isolation of two fragments, an N-terminal tryptic fragment having an Mr of 30,000 and a C-terminal tryptic fragment having an Mr of 50,000 [Legrand, Mazurier, Montreuil & Spik (1984) Biochim. Biophys. Acta 787, 90-96]. Both fragments possess a degree of organization lower than that of the native protein, as shown by the decrease of about 30% of the alpha-helical content observed by c.d. The two fragments are able to re-associate in neutral solutions, as shown by the isolation, by gel chromatography, of a re-associated 80 kDa N,C-tryptic complex having the chromatographic behaviour of the native lactotransferrin. Computer-based comparison of the measured c.d. spectrum of the mixture of N-tryptic and C-tryptic fragments (molar ratio 1:1) with the spectrum calculated by assuming one molecule of each fragment, shows that the alpha-helix content of lactotransferrin is restored. These results strongly suggest the existence of non-covalent and reversible interactions between the two lobes of lactotransferrin. In addition it was demonstrated that short peptide segments (residues 19-24, 45-58 and 264-276) are involved in the secondary-structure modifications referred to above.

Amino Acids↗
PubMed1986

[Preliminary results in favor of the existence of a major surface antigen, specific for Leishmania braziliensis braziliensis].

The comparative surface antigen study of 10 bolivian strains and 1 brazilian reference strain from L. b. braziliensis sub-species shows an important homogeneity within this group. All the strains tested so far present similar antigenic patterns with a major antigen at 72 kD. On the contrary, the comparative analysis of surface antigens of L. b. braziliensis with those of L. b. guyanensis, L. b. panamensis, L. mexicana amazonensis and L. donovani chagasi shows a large antigenic heterogeneity between the Leishmania sub-species and species we studied. The 72 kD antigen was only detected on L. b. braziliensis surface.

Animals↗
PubMed1985

[Light chain disease with terminal myocardiopathy].

The authors report a case of a 35 year old man with of congestive cardiac failure. Echocardiography showed diffuse hypokinetic wall motion with moderate parietal hypertrophy without dilatation. Post-mortem examination showed intramyocardial deposits of light chains identical to those observed in "in vivo" renal and liver biopsies. This rarely described disease has a poor prognosis. It is characterised by polyvisceral infiltrations of light chain monoclonal immunoglobulins. Renal disease is usually the main problem progressing rapidly to renal failure. Of the extra renal localisations, cardiac involvement would appear to be common and preoccupying in itself. Monoclonal plasmocytic proliferation is observed in all cases, the majority but not all being malignant (myeloma). The incidence of this condition is probably underestimated and may pass undetected if immunofluorescent techniques are not used. Myelomatous light chain cardiac disease could therefore be more common than amyloidosis with which it presents a number of common features.

Adult↗
PubMed1984

Human lactotransferrin: amino acid sequence and structural comparisons with other transferrins.

The complete amino acid sequence (703 amino acid residues) of human lactotransferrin has been determined. The location of the disulfide bridges has also been investigated. Computer analysis established internal homology of the two domains (residues 1-338 and residues 339-703). Each domain contains a single iron-binding site and a single glycosylation site (asparagine residues 137 and 490) located in homologous positions. Prediction of the secondary structure of the two homologous moieties of human lactotransferrin has also been performed. The present results allowed a series of comparisons to be made with human serum transferrin and hen ovotransferrin.

Amino Acid Sequence↗
PubMed1984

Characterization and localization of an iron-binding 18-kDa glycopeptide isolated from the N-terminal half of human lactotransferrin.

Mild treatment of iron-saturated human lactotransferrin by trypsin at pH 8.2 cleaves the molecule into a N-tryptic (Mr approximately equal to 30000) and a C-tryptic (Mr approximately equal to 50000) fragment, which have been isolated. Each of them carries a glycan moiety and keeps the property to bind reversibly one Fe3+. The N-tryptic fragment has been submitted to a second tryptic digestion which led to an iron-binding glycopeptide fragment with a molecular weight of about 18500. This fragment, the smallest iron-binding peptide isolated up to now from a transferrin, includes the ND2 domain of human lactotransferrin.

Carbohydrates↗
PubMed1978

Nuclear scattering radiography of the spine and sphenoid bone.

Nuclear scattering radiographs of a portion of a spine and a sphenoid bone have been obtained using a 1 GeV proton beam. The ability of the method to yield three-dimensional representations is illustrated by three series of adjacent pictures corresponding to the three orthogonal planes (elementary volume: 5.2 mm3 and 0.9 mm3). The sensitivity of the method is discussed. Nuclear scattering radiographs are compared with ones obtained by conventional X-ray tomography and computed tomography. Nuclear scattering radiography also may be used to analyze the partition of hydrogen within the tissures. Hydrogen radiographs obtained in this way are shown.

Elementary Particles↗
PubMedDate not supplied

[New blood transfusion partners in France].

The French Blood Agency, created in 1993, controls all aspects of the blood transfusion system. It is responsible for restructuring the blood transfusion system and for Good Manufacturing Practices. All incidences are reported to the blood monitoring system which also obtains further descriptions of such incidents. Blood transfusion policies have been modified to include monitoring of blood-associated morbidity. Successive reforms have led to the establishment of a new public system for blood transfusion. New structures and more formal designation of responsibilities are needed. The function of these new structures is to better control transfusion activities and prevent unknown risk.

Blood Banks↗
PubMedDate not supplied

Characterization of lactotransferrin receptor in epithelial cell lines from non-malignant human breast, benign mastopathies and breast carcinomas.

The aim of this study was to investigate the presence of lactotransferrin receptor on breast non-malignant SV-40 immortalized cells (HBL100 and NB54T), benign mastopathy immortalized cells (NPM14T and NPM21T1), hst oncogene transformed HBL100 cell line (tumorigenic HH9 cells) and breast carcinoma cells (T47D, MCF7, VHB1, BT20 and MDA-MB 231). Flow cytometry analyses of the reversible binding of lactotransferrin labeled on its glycan moiety with fluorescein indicate, for the first time, that all these epithelial breast cell lines, express a specific lactotransferrin receptor. The binding parameters of [125I]-lactotransferrin to non-malignant cells, hst oncogene transformed cells and benign mastopathy cells are of the same order of magnitude as those determined for activated lymphocytes and for cancerous breast cell lines, except for MDA-MB 231 cells. MDA-MB 231 cells bind lactotransferrin with the lowest affinity and, in contrast to other analyzed breast cells, are not recognized by antibodies directed against lymphocyte lactotransferrin receptor. These results suggest that MDA-MB 231 lactotransferrin receptor is different from that characterized at the cell surface of other breast cells. In conclusion, since the lactotransferrin receptor expression was not enhanced at the surface of cancerous cell lines and was not altered by the oncogene transformation of a normal cell (HBL100) to a tumorigenic cell (HH9), the lactotransferrin receptor cannot be considered as a marker of tumor progression.

Breast↗
PubMedDate not supplied

[Coronary artery disease associated to diabetes mellitus].

Diabetes mellitus represents a major coronary risk factor. Diabetes promotes atherosclerotic plaque development through different mechanisms among which oxidative stress induced by hyperglycaemia appears to play a major role. Knowledge of pathophysiologic mechanisms associated with diabetes helps to better understand the rationale for treatment. Besides a tight control of all cardiovascular risk factors, prescription of drugs aiming of stabilization or even reduction of atherosclerosis should be systematically recommended. These drugs include statines, ACE inhibitors and aspirin eventually combined with clopidogrel. The use of beta blockers should be encouraged in case of stable angina. Finally, any patient with symptomatic modification suggesting acute coronary syndrome should be considered for myocardial revascularization.

Angiotensin-Converting Enzyme Inhibitors↗
PubMedDate not supplied

[Intraepithelial carcinoma of the cervix uteri. 1) Cytologic detection in gynecologic practice. Our exerience with 15,000 smears].

The best results in screening for subclinical cancer of the cervix are given by cytological studies. The authors in reviewing their experience in this method of screening studied the result of 15,000 smears which gave a diagnosis of 37 cases of intra-epithelial carcinoma of the cervix, which means 1 case of carcinoma in situ diagnosed in every 400 smears. Although the technique is very simple it has to be carried out according to strict criteria at the time of taking the smear, of fixing it immediately and of staining it. There is a group of patients who are at high risk about the age of forty, when there is a marked influence due to parity. But only a systematic policy will bring about diagnosis of pre-invasive carcinoma in cases where the cervix is clinically healthy. The cytology is usually characteristic, though the diagnosis may be difficult during pregnancy, or when hormone contraception is being used or when there is a trichomonas infection present. This explains why we find false positives in 0.03 per cent of cases in this study and false negatives in 0.03 per cent of cases. Their rarity means that the method is 99.94 per cent reliable. Finally, the cervical smear gives an opportunity for studying the vaginal microbial flora as well as the cyto-hormonal state.

Adult↗
PubMedDate not supplied

[Intra-epithelial carcinoma of the cervix uteri. Our experience with treatment, the role of conization].

The authors re-emphasize that the sure diagnosis of carcinoma of the cervix depends on histology; having considered a series of 15,000 smears in an article on cytological screening for carcinoma of the cervix. They show that the main prop of this histological examination should definitely be conisation. They furthermore prepare an inventory of the different possible methods of treatment of intra-epithelial carcinoma, stating for each method the advantages and disadvantages of the method. Their attitude to treatment is conservative, and they believe that conisation in every case is sufficient when complete removal of the in situ lesion is carried out whatever the age of the patient is. They state the limits of this method and define clearly the contra-indications for such a scheme of treatment, which can only be carried out routinely with the absolutely necessary cooperation of a cytology laboratory and faultless histology.

Adult↗