Search PubMed⌕ Search

Biomedical subjects

A Le Treut

Publications and source records attributed to A Le Treut.

At least 37 records · Page 2Linked to original sources
PubMed1989

Pathophysiological variations in the rat liver plasma membrane serine proteinase activity.

The effects of fasting, diabetes, cholestasis, two-third hepatectomy and adrenalectomy on the rat liver plasma membrane serine proteinase activity were studied. Our results show a significant decrease of the enzyme activity during fasting (-50%), during experimental diabetes (-50%), in regenerating liver after partial hepatectomy (-70%) and after extrahepatic cholestasis (-70%). No modifications are noted when the rats are bilaterally adrenalectomized. These findings suggest that the enzyme activity may be linked to the level of circulating insulin, and may be regulated in physiological cellular proliferation so as to prevent undesirable protein degradation.

Adrenalectomy↗
PubMed1989

[Diagnosis of bilateral secondary tumors of the kidney. Contribution of cytology. Apropos of 2 cases].

The authors report bilateral secondary tumors of the kidney in two patients: one previously treated for an epidermoid tumor, the other for an anaplastic bronchial tumor. In both patients, clinical and radiological features were those of a malignant process. Scan-guided percutaneous fine needle aspiration provided the material necessary to make a definitive cytological diagnosis; it was thus possible to assess the malignancy and recognize the histological type of lesions.

Adult↗
PubMed1989

Effects of perhexiline maleate on asialo-orosomucoid receptor endocytosis and recycling in HTC cells.

Perhexiline is a lysosomotropic agent which has proved to be very valuable to certain patients suffering from angina pectoris. However long-term administration of the drug may induce hepato- and neuro-toxicity. Using HTC cells (a rat hepatoma-derived cell line) whose plasma membranes were labeled with NaB[3H]4 after oxidation by NaIO4, endocytosis and recycling of labeled asialo-orosomucoid (ASOR) receptors were investigated in the presence of 50 mumols/l perhexiline maleate. The results demonstrate that the drug induces a significant decrease of the rate of both the internalization and the recycling of ASOR receptors. The mechanisms responsible for these effects have not yet been elucidated. However, the current findings may be related to the previously observed inhibitory effect of perhexiline on cellular (Na+, K+)-ATPase and Mg++-ATPase activities. Our findings would then reflect insufficient cellular energy production, resulting from depressed ATP hydrolysis in the presence of perhexiline.

Animals↗
PubMed1989

[Adrenal myelolipoma and Castleman's pseudotumor. A case of association in a retroperitoneal tumor].

The authors report a case of a voluminous retroperitoneal tumor as an incidental finding in a patient with acute urine retention induced by an ovarian compressive cyst. Radiological findings supported the hypothesis of a malignant tumor. The histological examination of the surgical specimen only permitted the diagnosis and showed the association of an adrenal myelolipoma with a Castleman's pseudo-tumor.

Adrenal Gland Neoplasms↗
PubMed1988

Adjuvant trial for stage II receptor-positive breast cancer: CMF vs. CMF + tamoxifen in a single centre.

The purpose of a randomized trial achieved in a single centre (Fondation Bergonié, Bordeaux, France) was to compare chemotherapy alone (intravenous CMF) versus chemotherapy and hormonotherapy (CMF plus tamoxifen-30 mg per day during 2 years), for patients with stage II breast carcinoma and positive values of estrogen and/or progesterone receptor (EPR) (greater than 10 and greater than 15 fmoles mg protein-1 respectively). Three hundred and thirty four women treated by surgery +/- radiotherapy are included in this trial from 06.01.81 to 12.31.84. No patient is lost for follow-up. Eight are excluded. Three hundred and twenty six patients are evaluable with a 38 month median follow-up. For EPR assay, the dextran charcoal micromethod was used in the same centre. The two groups are identical as far as age, hormonal status, TNM, EPR values, and histological features are concerned. Analysis of results shows a significant improvement of relapse free survival (p = 0.018) and also overall survival (p = 0.04) for the CMF+ tamoxifen group.

Adult↗
PubMed1988

Inhibition of (Na+,K+)-ATPase and Mg++-ATPase by a lysosomotropic drug: perhexiline maleate.

Human clinical observations and in vivo studies have shown that the amphiphilic drug perhexiline maleate is responsible for lipidosis storage disorders. When the drug was incubated in vivo with rat brain homogenates, the ouabain-sensitive (Na+,K+)-ATPase and the Mg++-ATPase activities were inhibited. 50% inhibition occurred at the drug concentrations 5.10(-5) M for (Na+,K+)-ATPase and at 10(-4) M for Mg++-ATPase, respectively. Kinetic studies performed on rat brain homogenates showed a mixed type inhibition of these enzymes by perhexiline maleate. The effect of other lysosomotropic drugs (imipramine, chlorpromazine, thioridazine and tamoxifen) on (Na+,K+)-ATPase and on Mg++-ATPase activities was found to be similar to that induced by perhexiline maleate. These results indicate that the inhibitory effect of perhexiline maleate on (Na+,K+)-ATPase and Mg++-ATPase may be a common feature shared by the lysosomotropic drugs.

Animals↗
PubMed1988

[The coefficient of saturation of iron in transferrin].

Theoretical iron fixation capacity of transferrin (FCT) can be calculated on its immunochemical titration: (FCT (mumol/l = transferrin (g/l) x 25). Today, its reckoning is more advisable to serum total iron binding capacity measurement. The authors studied the effects of this new proceeding upon usual values interval of transferrin saturation (i.e. serum iron/FCT ratio). The mean value and the distribution of transferrin saturation appear displaced with regard to those achieved by chemical measurement of serum total iron binding capacity. We discuss interpretation of transferrin saturation related to its methods of determination and its semiological interest.

Adolescent↗
PubMed1988

[Imaging of sarcomas of soft tissue].

Modern imaging of soft tissue sarcomas now includes ultrasounds, CT and MRI. These new techniques allow a better evaluation of initial local extension, of the response to treatment and are able to detect local recurrences early.

Follow-Up Studies↗
PubMed1988

[Imaging of bone sarcomas].

Radiological study of bone sarcomas has been improved for the last ten years. Standard X-ray analysis is now more precise. CT and MRI are presently playing an important role for pretreatment local evaluation, assessment of treatment effectiveness and detection of recurrences.

Bone Neoplasms↗
PubMed1986

Partial purification and characterization of a serine endopeptidase from rat liver plasma membranes.

A serine endopeptidase was partially purified from rat liver plasma membranes by using a four-step procedure: solubilization with N-lauroylsarcosine; Ultrogel AcA-34 chromatography; CM Affi-Gel blue chromatography; agarose-soybean trypsin inhibitor chromatography. This enzyme was found to hydrolyze casein and various chromogenic peptide substrates; highest activity occurred with H-D-Val-Leu-Arg-p-nitroanilide, reported to be a specific substrate for human glandular kallikreins. The enzyme was heat-sensitive, showed a pH optimum between 8.0 and 9.0 and was inhibited by D-Phe-L-Phe-L-Arg-CH2Cl, aprotinin, diisopropyl fluorophosphate (DFP), soybean trypsin inhibitor, phenylmethylsulphonyl fluoride, leupeptin, antipain and dithiothreitol. This liver plasma membrane proteinase has an apparent molecular weight of about 30 000 as determined by Ultrogel AcA-34 chromatography and by autoradiography of [3H]DFP-labelled protein electrophoresis.

Animals↗
PubMed1986

[Radiographic aspects of galactoceles].

The authors report two cases of galactoceles with unusual radiographic patterns, different from those ordinarily described either (opacity or radiocrescent); that is an aspect with a clear superior crescent related to a level between milk and fat, included in a localized galactophoric dilatation.

Adult↗
PubMed1984

Complex structure of human bronchial mucus glycoprotein.

Human bronchial mucus glycoproteins or mucins were isolated from the sputum of two patients by a method avoiding reducing agents and involving water extraction and gel filtration on Sepharose CL-2B in 6 M guanidinium chloride. The chemical analysis indicated approximately 25-40% lipid. The amino acid and carbohydrate analysis differ quantitatively from that of mucins purified after prior reduction of mucus. These fractions also have a higher proportion of aspartic and glutamic acids than that of the mucins from reduced sputum. These mucins are still contaminated by small amounts of peptides but do not seem to contain disulfide-attached cross-linking protein. Human bronchial mucins have a strong tendency to form aggregates except in 6 M guanidinium chloride. Electron microscopy performed with various procedures indicates the presence of both micelles and flexible threads measuring 200-1000 nm. Delipidation removes most of the micellar forms. Thereafter mucins appear mainly as polydisperse flexible extended threads and also as aggregates. These features of bronchial mucins do not fit with the generally accepted idea of mucin subunits linked by disulfide bridges (unless they are linked end to end) and alternatively favour a model where mucin molecules behave like filaments that could easily aggregate according to the solvent system (mucin concentration, absence of dissociating conditions).

Amino Acids↗
PubMed1983

Serum angiotensin-converting enzyme levels in patients with chronic renal failure.

Disagreement concerning serum angiotensin-converting enzyme (ACE) levels in patients with chronic renal failure has been observed in recent reports. Because ACE is considered as a useful tool for the diagnosis and management of sarcoidosis, and because chronic renal failure may be associated with sarcoidosis, the present work was designed to reinvestigate the possible changes of serum angiotensin-converting enzyme activity in a series of 36 non-hemodialysed consecutive patients with chronic non-sarcoid renal failure. Enzyme activity was significantly lower (p less than 0.004) in the patients (15.8 +/- 5.0 units/ml, mean value +/- 1 SD) than in 47 healthy controls (20.2 +/- 7.6 units/ml, mean value +/- 1 SD). Serum angiotensin-converting enzyme and creatinine clearance values were significantly correlated in these patients (p less than 0.0002). These results indicate that, in non-hemodialysed patients with chronic renal failure, serum angiotensin-converting enzyme levels may not be useful in establishing the diagnosis of sarcoidosis.

Adolescent↗
PubMed1982

Serum lysosomal acid hydrolase activities in Graves' disease.

The activities of seven lysosomal enzymes (alpha-D-glucosidase, beta-D-galactosidase, beta-D-glucuronidase, hexosaminidase, alpha-L-fucosidase, alpha-D-mannosidase, acid phosphatases) were studied in the serum of 31 untreated patients with Graves' disease, 30 treated hyperthyroid patients whose clinical abnormalities had disappeared and whose hormones had returned to euthyroid levels, and 34 controls. The hyperthyroid state is characterized by increased serum levels of alpha-D-glucosidase, beta-D-glucuronidase, hexosaminidase and especially of alpha-L-glucosidase and alpha-D-mannosidase. In contrast, neither beta-D-galactosidase nor acid phosphatases serum levels were significantly modified. After antithyroid treatment, the activities of these enzymes returned to normal levels, except for alpha-D-mannosidase. The interpretation of these changes in serum acid hydrolases activities is controversial.

Acid Phosphatase↗