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Biomedical subjects

C Scheiner

Publications and source records attributed to C Scheiner.

At least 55 records · Page 3Linked to original sources
PubMed1989

[Detection of acute rejection by Doppler echocardiography in orthotopic cardiac transplantation. Prospective comparative study with endomyocardial biopsy].

In a prospective study of 23 patients who had undergone orthotopic heart transplantation we tried to assess the value of doppler-echocardiography in the detection of acute graft rejection. For this purpose, 220 echocardiographic records were compared with the results of endomyocardial biopsies performed at an interval of less than 12 hours. The parameters investigated by TM and two-dimensional echocardiography were: morphological parameters (including septal echodensity), left ventricular mass and systolic function parameters. Diastolic parameters (isovolumetric relaxation time [IVR], transmitral gradient half-decrease time [T 1/2] and proto-end-diastolic mitral velocity ratio [E/A] were measured by TM echocardiography and pulsed doppler velocimetry. The best doppler-echocardiographic criteria for graft rejection were a more than 15 ms reduction of IVR, a more than 15 p. 100 increase of myocardial mass, and a more than 30 p. 100 increase of teh E/A ratio, the corresponding sensitivities for histological rejection being 82, 76 and 74 p. 100 respectively. In contrast, T 1/2 and systolic function studies seemed to be disappointing. Finally, the increase of septal echodensity enabled rejection to be diagnosed with an excellent (92 p. 100) specificity but an insufficient sensitivity. Thus, none of the parameters measured were sensitive enough, taken separetely, to replace endomyocardial biopsy. However, the combined use of the most sensitive of them should make it possible to reduce the frequency of systematic biopsies.

Acute Disease↗
PubMed1985

[Registry of cancers in children in the regions of Provence, the Alps, Côte d'Azur and Corsica. Setting up and evaluation of the year 1984].

Epidemiology is a promising clinical way for research on cancer. A population based pediatric cancer registry was opened since January 1984 in 2 regions of south-eastern France. Its purpose is to analyse childhood cancer incidence and possible variations. A case-control study on risk factors was set up at the same time. Registration procedures and 1984 data are reported. The observed incidence is 11.86 new cancer cases/10(5) children/year.

Adolescent↗
PubMed1983

[Pseudomyxoma peritonei: a case with multiple metastases. Ultrastructural study and chemical analysis of the mucoid substance].

A patient with spreading pseudomyxoma peritonei probably caused by a tumor of the appendix showing suggestive clinical features is presented. The long evolution was marked by the discovery of gelatinous substance in the stools and in the lumen of the gut, and the appearance of distant metastasis in the lungs, adrenal glands and lymph nodes. Histochemical studies showed that periodic Shiff acid and Alcian blue were fixed by the mucoid substance. The use of toluidin blue (pH 1) revealed metachromosia. Electron microscopy ascertained the presence of enterocytes and mucous cells and revealed a more obvious nuclear disorganisation than by histological microscopy. Biochemical study showed that the mucoid substance extracted from the pseudomyxoma was rich in carbohydrates and could be identified as a mucin on the basis of the composition of its monosaccarides and of the alkali-lability of its glycanprotein linkages. The mucin was weakly hydrolysed by trypsin in vitro but was deeply attacked by the same enzyme after desialylation. These results: a) confirm the possibility of observing spreading distant metastasis in the pseudomyxoma peritonei; b) underline the potential interest of electron microscopic study in case of wavering diagnosis; c) show that the mucoid substance belongs to the group of neutral sulfomucins; d) legitimate, in the future, a trial of palliative treatment by neuraminidase in such cases.

Humans↗
PubMed1982

[Pseudo-tumorous panniculitis of the mesentery. An unusual initial stage of acute lupus erythematosus in a 10-year-old girl].

Lupus panniculitis usually affects the hypodermis and the dermis profundus (Irgang's lupus profundus). In our case, the systemic lupus erythematosus was preceded by an intraabdominal panniculitis, occurring as a voluminous tumor. Histological examination showed the usual picture of panniculitis, but there were also severe fibrinoid necrotic lesions, which should have alerted us. Lupus must be included among the etiologies of intraabdominal panniculitis.

Acute Disease↗
PubMed1980

A beta-like DNA polymerase activity in the slime mold Dictyostelium discoideum.

Two distinct DNA polymerases (DNA nucleotidyltransferases) have been partially purified from exponentially growing cells of the slime mold Dictyostelium discoideum. The major DNA polymerase activity, DNA polymerase A, has physical and enzymatic properties similar to DNA polymerase alpha from vertebrate cells. DNA polymerase B, representing less than 10% of the polymerase activity in homogenates, is similar to DNA polymerase beta from vertebrate cells in that its activity is not inhibited by N-ethylmaleimide, aphidicolin, or KCl at a concentration below 200 mM. Like DNA polymerase beta, the activity of Dictyostelium DNA polymerase B is sensitive to 2', 3'-dideoxythymidine 5'-triphosphate. However, it differs from vertebrate DNA polymerase beta in that it chromatographs as an acidic protein and has an apparent molecular weight of 70,000. Previous reports of the absence of a beta-like DNA polymerase in D. discoideum apparently resulted from inadequate extraction and assay conditions for the enzyme. It seems quite probable from the results of this study and those of other studies (e.g., yeast and Tetrahymena pyriformis) that lower eukaryotic organisms, as well as vertebrates and prokaryotes, contain more than one form of DNA polymerase.

Aphidicolin↗
PubMed1980

Plasminogen activator and the membrane of transformed cells.

Studies have been conducted on the enzyme plasminogen activator (PA) in cultures of RSV transformed CEF. The enzyme exists in two forms, a soluble extracellular form (PAex) and a cell-associated form that is firmly bound to specific membranes (PAmem) when cell homogenates are subfractionated. Both forms of the enzyme are induced in a synergistic fashion by treatment of RSVCEF with the tumor promoter phorbol myristate acetate (PMA). The induction of the enzyme by PMA has allowed for the purification of PAex. In addition, PMA treatment of RSVCEF causes pronounced morphological alterations in culture. The use of protease inhibitors, [3H]-DFP, and a direct fluorometric assay for PA indicate that the morphological changes are due to the direct catalytic action of PA, independent of plasminogen, until now its only known natural substrate. Recent experiments suggest that PAmem is responsible for the morphological changes and that residual amounts of LETS protein are lost from the cell surface and substratum coincident with the morphological changes. The possible role of serine proteases in regulatory cellular behavior in transformed or tumor promoter-treated cells is discussed.

Animals↗