PubMed Health⌕ Search

Biomedical subjects

L Donner

Publications and source records attributed to L Donner.

At least 19 recordsLinked to original sources

Reduction to homozygosity at the SIS/PDGF-2 locus in human mesenchymal tumors.

Enhanced expression of the human SIS/PDGF-2 gene has been reported in a number of human cell lines, sarcomas, and glioblastomas. We have analyzed the SIS/PDGF-2 gene for structural alterations in fresh human tumors. DNA samples from 79 patients with solid tumors (63 mesenchymal tumors, 12 lung carcinomas, 4 breast carcinomas) were examined and compared with DNA samples from 50 leukemia patients and 14 unrelated individuals without malignant neoplasms. When DNA samples were digested with a HindIII restriction endonuclease, Southern blot analysis demonstrated two distinct bands (21kb and 18kb) after hybridization to the SIS/PDGF-2 gene probe. A pedigree analysis of a 43-member family indicated that these allelic variants segregated in a Mendelian fashion. There was, however, tumor specific allele loss in 18% of the mesenchymal tumors analyzed, which may indicate a common etiology for this tumor type.

Cell Line↗

Some fibrinolytic properties of the human arteries and veins walls.

The plasminogen activator of normal and atherosclerotic different arteries was studied with the histochemical method of Todd. An increase of plasminogen activator in atherosclerotic arteries of adventitia was found. The inhibition of plasmin fibrinolysis of intima-media and adventitia of normal and atherosclerotic different arteries was studied by means of the slide sandwich technique according to Noordhoek Hegt. In atherosclerotic arteries there was an increase of plasmin inhibitory activity of the intima-media layer in comparison with normal arteries. The mean plasmin inhibitory activity was higher in the vein wall of lower part of the body than in the higher one.

Arteries↗

Immunoreactivity of paraffin-embedded normal tissues and mesenchymal tumors for smooth muscle myosin.

Immunohistochemical study of smooth muscle myosin, a protein distinct from skeletal, cardiac, or nonmyogenous myosins in paraffin-embedded normal tissues and benign and malignant mesenchymal tumors revealed its strong expression in normal smooth muscle, capillary endothelium, and pericytes. All benign smooth muscle tumors with exception of gastric leiomyomas and few other leiomyomas of the gastrointestinal tract displayed strong or moderate immunoreactivity. On the other hand, strong or moderate immunoreactivity was detected in only eight of 28 spindle-cell leiomyosarcomas, as well as in 13 out of 27 malignant fibrous histiocytomas and three out of nine malignant hemangiopericytomas, while epithelioid leiomyosarcomas, fibrosarcomas, malignant schwannomas, and synovial sarcomas were negative or only weakly positive. Our results demonstrate that, while smooth muscle myosin is a very good marker of normal smooth muscle and benign smooth muscle tumors, it is expressed in diagnostically significant amounts in less than a third of spindle-cell leiomyosarcomas and none of the studied epithelioid leiomyosarcomas.

Female↗

McDonough feline sarcoma virus: characterization of the molecularly cloned provirus and its feline oncogene (v-fms).

The genetic structure of the McDonough strain of feline sarcoma virus (SM-FeSV) was deduced by analysis of molecularly cloned, transforming proviral DNA. The 8.2-kilobase pair SM-FeSV provirus is longer than those of other feline sarcoma viruses and contains a transforming gene (v-fms) flanked by sequences derived from feline leukemia virus. The order of genes with respect to viral RNA is 5'-gag-fms-env-3', in which the entire feline leukemia virus env gene and an almost complete gag sequence are represented. Transfection of NIH/3T3 cells with cloned SM-FeSV proviral DNA induced foci of morphologically transformed cells which expressed SM-FeSV gene products and contained rescuable sarcoma viral genomes. Cells transformed by viral infection or after transfection with cloned proviral DNA expressed the polyprotein (P170gag-fms) characteristic of the SM-FeSV strain. Two proteolytic cleavage products (P120fms and pp55gag) were also found in immunoprecipitates from metabolically labeled, transformed cells. An additional polypeptide, detected at comparatively low levels in SM-FeSV transformants, was indistinguishable in size and antigenicity from the envelope precursor (gPr85env) of feline leukemia virus. The complexity of the v-fms gene (3.1 +/- 0.3 kilobase pairs) is approximately twofold greater than the viral oncogene sequences (v-fes) of Snyder-Theilen and Gardner-Arnstein FeSV. By heteroduplex, restriction enzyme, and nucleic acid hybridization analyses, v-fms and v-fes sequences showed no detectable homology to one another. Radiolabeled DNA fragments representing portions of the two viral oncogenes hybridized to different EcoRI and HindIII fragments of normal cat cellular DNA. Cellular sequences related to v-fms (designated c-fms) were much more complex than c-fes and were distributed segmentally over more than 40 kilobase pairs in cat DNA. Comparative structural studies of the molecularly cloned proviruses of Synder-Theilen, Gardner-Arnstein, and SM-FeSV showed that a region of the feline-leukemia virus genome derived from the pol-env junction is represented adjacent to v-onc sequences in each FeSV strain and may have provided sequences preferred for recombination with cellular genes.

Animals↗

Tracking: an answer to psychiatry's recruitment problem?

Part of psychiatry's recruitment problem stems from large-scale defections among students who were planning careers in psychiatry when they entered medical school. The authors present data indicating that University of Maryland freshmen who preferred psychiatry were more than four times as likely to enter psychiatric residency training if they participated in the Combined Accelerated Program in Psychiatry, a continuous 4-year medical school track, than if they pursued the regular undergraduate psychiatry program. The authors believe that an enthusiastic psychiatric faculty intimately involved with students over an extended period of time was the crucial factor neutralizing antipsychiatric socialization experiences in medical school.

Attitude↗

Management of advanced Hodgkin's disease in remission.

Patients with Hodgkin's disease (stage IIIB and IV) after being rendered with combination chemotherapy disease-free, were alternatively allocated to either a group receiving levamisole treatment (Decaris) or to a control group receiving no further therapy until there was evidence of recurrent disease. Laboratory examinations showed that impaired cell mediated immune responses found after termination of intensive chemotherapy were favourably influenced by levamisole treatment. In addition, the duration of remission seems to be longer in the levamisole treated group, although the limited number of patients in the study do not allow a definite conclusions to be drawn.

Cell Migration Inhibition↗