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D Birnbaum

Publications and source records attributed to D Birnbaum.

At least 289 records · Page 16Linked to original sources
PubMed1987

Localization of the mcf.2 transforming sequence to the X chromosome.

A transforming sequence was identified using co-transfection of DNA from the human mammary carcinoma cell line MCF-7 and of a G418 resistance gene into NIH 3T3 cells, followed by tumor formation in athymic mice. This sequence, named mcf.2, was molecularly cloned. A transforming activity resides in a cosmid clone of 42 kb. mcf.2 did not cross-hybridize with the known oncogenes tested. In situ hybridization localized it on the X chromosome, probably at q27. This localization was confirmed by hybridization to a panel of human--rodent cell line DNAs.

Animals↗
PubMed1987

Large scale physical mapping in the q27 region of the human X chromosome: the coagulation factor IX gene and the mcf.2 transforming sequence are separated by at most 270 kilobase pairs and are surrounded by several 'HTF islands'.

In spite of the large amount of genetic data obtained on the X chromosome and of the availability of many cloned sequences little is known about the physical map of this chromosome. The construction of large-scale restriction maps is now possible with pulsed field gel methods and data has recently been obtained in the region of band Xq28. We present here results of physical mapping in the Xq27 region, i.e. proximal to the fragile site at Xq27.3 associated with mental retardation, and show physical linkage between the coagulation factor IX gene and the mcf.2 transforming sequence recently localized to Xq27. Our data also indicate partial methylation of some sites in this region, and locate several 'HTF islands', i.e. CpG-rich, unmethylated sequences, containing several sites for 'rare cutter' enzymes, which are believed to be associated with expressed 'housekeeping' genes.

Base Composition↗
PubMed1987

Identification of a lys2 mutant of Candida maltosa by means of transformation.

We have isolated five mutants of Candida maltos, which lack the 2-aminoadipate reductase activity, an enzyme involved in the lysine biosynthesis. By means of complementation analysis using protoplast fusion, the isolated mutants were divided into two complementation groups. Thereof the C. maltosa strain G457 could be transformed by the plasmids pDP12 and pDP13, which contain the LYS2-coding gene of Saccharomyces cerevisiae. On the basis of our presented results obtained by studies on hybridization, stability, and recovery of plasmids from C. maltosa transformants, we suggest that transformation does proceed integratively.

Aldehyde Oxidoreductases↗
PubMed1987

[Aortic valve replacement with a bioprosthesis--which type of prosthesis?].

308 patients after aortic valve replacement by bio-prostheses were evaluated by questionnaire. The aim of the study was to estimate factors of risk for morbidity, which could be referred to the different xenogenic valve materials. After an average period of 41 months there was no statistical difference in postoperative status, such as exercise capacity, rate of survival and of freedom from thromboembolic events or repeat surgery. Although results of the early and intermediate postoperative period are satisfying with both types of valve prostheses a longer period of observation is required to draw distinct conclusions for xenogenic material related complications.

Aortic Valve↗
PubMed1987

3-amino-triazole effects on the eye of young and adult rabbits in the presence and absence of hydrogen peroxide.

3-aminotriazole (3AT) is known to reduce catalase levels in ocular tissues when given intravenously or orally. Rabbits were given either 4 ml/kg of a 3M solution of 3AT intravenously or a 2% solution as drinking fluid. Intravenous 3AT administration was followed at 4 hrs by an intracameral injection of hydrogen peroxide (H2O2) to give an aqueous humor concentration of 3.2 mM in young (4-6 weeks of age) and a 3.3 mM in adult (6 months of age) rabbits. Tissues were taken for microscopy at either 6 or 24 hours after intracameral H2O2. Neither oral nor intravenous 3AT alone in adult rabbits, or intravenous 3AT in young rabbits, had any effect on either iris, ciliary process, or corneal endothelial morphology. After oral 3AT in adult rabbits, H2O2 caused highly edematous ciliary processes with dilated vessels; corneal endothelial cells were swollen. Previous studies in adult and young rabbits have shown that intracameral H2O2 alone caused few morphological changes in young, but marked changes in the adult that correlated with the 35 to 50% lower catalase levels found in iris and corneal endothelium, respectively, in adult ocular tissues. Young rabbits pre-treated with intravenous 3AT, when examined at 6 and 24 hours after intracameral H2O2, showed swollen ciliary processes, vessel dilation, alteration of the pigment epithelium and corneal endothelial damage. In non 3AT-treated young rabbits, H2O2 caused only minor morphological changes. In adult animals at 6 and 24 hours after intracameral H2O2 the ciliary processes were edematous in the absence of 3AT; after intravenous 3AT and intracameral H2O2 the changes were even more marked, with very severe swelling of ciliary processes and corneal endothelial damage. It is apparent that the decrease in catalase caused by 3AT allows H2O2 to induce damage even in young animals where it usually does not induce morphological changes. In adult animals, the effects of H2O2 are enhanced in the presence of 3AT.

Administration, Oral↗
PubMed1987

The quality plan.

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Administrative Personnel↗
PubMed1987

[Activated oncogenes in human tumors].

ras oncogenes are cellular genes altered by point mutation in 10 to 30% of human tumors. Under this mutated form they play a role in the malignant process, probably in association with other oncogenes. The different ras genes identified in human cancers, the point mutations that activate the ras genes and the properties of the ras proteins are described.

Animals↗
PubMed1987

Human ros1 and mas1 oncogenes located in regions of chromosome 6 associated with tumor-specific rearrangements.

Oncogenes have been implicated in tumorigenesis based on their localization to chromosomal sites associated with tumor-specific structural rearrangements. We have mapped the human ros1 (formerly mcf3) and mas1 oncogenes to the distal half of chromosome 6q, within a region frequently rearranged in malignant cells. Chromosomal mapping of these two new human transforming genes may help elucidate the involvement of the long arm of chromosome 6 in diverse tumor types.

Cell Line↗
PubMed1986

Physical mapping and genome organization of mitochondrial DNA from Candida maltosa.

Mitochondrial (mt) DNA of the ascomycetous yeast Candida maltosa was isolated and characterized. The mtDNA is circular and the size estimated from restriction analysis performed with 7 endonucleases was 52 kb pairs. A restriction map was constructed, using the cleavage data of four endonucleases. Using mt genes from Saccharomyces cerevisiae, six structural genes (large rRNA, apocytochrome b, cytochrome c oxidase subunit I and subunit II, ATPase subunit 6 and subunit 9) were located on the C. maltosa chondriome by cross hybridization experiments. The comparison between the mt genomes of C. maltosa and six other yeasts showed differences in the overall genome organization.

Candida↗
PubMed1986

Serum bactericidal activity of two newer quinolones against Salmonella typhi compared with standard therapeutic regimens.

The bactericidal activity of two newer quinolones, ciprofloxacin and ofloxacin, against eight strains of Salmonella typhi was examined by the serum dilution test and studies of bacterial killing kinetics in human serum, and compared to standard regimens. Bactericidal titers for ciprofloxacin ranged from 1:388 to 1:119 two hours and from 1:119 to 1:57 six hours after volunteers received an oral dose of 500 mg. The respective titers obtained after a 200 mg oral dose of ofloxacin were somewhat lower, but still exceeded 1:16 in all instances. Studies of bacterial killing kinetics demonstrated a rapid bactericidal action of both drugs against all strains tested. Compared to the classical anti-typhoid agents chloramphenicol, cotrimoxazole and amoxicillin, the new quinolones showed both markedly higher bactericidal titers and more rapid killing of Salmonella typhi in human serum.

Adult↗
PubMed1986

Characterization of an activated human ros gene.

A human oncogene, mcf3, previously detected by a combination of DNA-mediated gene transfer and a tumorigenicity assay, derives from a human homology of the avian v-ros oncogene. Both v-ros and mcf3 can encode a protein with homology to tyrosine-specific protein kinases, and both mcf3 and v-ros encode a potential transmembrane domain N terminal to the kinase domain. mcf3 probably arose during gene transfer from a normal human ros gene by the loss of a putative extracellular domain. There do not appear to be any other gross rearrangements in the structure of mcf3.

Amino Acid Sequence↗
PubMed1986

[Cardiogenic embolisms following silent anterior wall infarct].

A 33-year-old man had suffered recurrent arterial embolisms. Echocardiography identified as the most likely cause a large mobile mass in the left ventricle. Initially a primary heart tumor was discussed, but the ECG finding of an anterolateral scar and an angiographically proven LAD-stenosis were suspicious of an organized thrombus of the left ventricle. After surgical excision, histological analysis classified the mass as an organized thrombus.

Adult↗