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Biomedical subjects

D Raben

Publications and source records attributed to D Raben.

25 records · Page 2Linked to original sources
PubMed1989

Molecular characterization and comparison of simian immunodeficiency virus isolates from macaques, mangabeys, and African green monkeys.

Simian immunodeficiency virus (SIV)/Mne has been inoculated into three species of macaques and into baboons. Virus was isolated from all the macaques who subsequently died at 15 to 120 weeks (mean 80 weeks) with various manifestations of immune deficiency. Individual animals varied in their viral antibody profile as a function of time after infection. Independent SIV isolates obtained from African green monkeys and magabeys were compared to SIV/Mne for their ability to replicate in lymphocytes and macrophages and with respect to the immunological relatedness of their viral proteins. Antibodies present in human immunodeficiency virus-2 (HIV-2)-infected individuals were readily detected by the virus produced by a single-cell clone of SIV/Mne.

Animals↗
PubMed1981

Growth inhibitory protein(s) in the 3T3 cell plasma membrane. Partial purification and dissociation of growth inhibitory events from inhibition of amino acid transport.

It has been reported previously that a plasma membrane-enriched fraction from 3T3 cells arrests the growth of sparse 3T3 cells early in the G1 phase of growth (Whittenberger et al., '78, '79). Addition of membranes to sparse 3T3 cells also results in a decrease of the rate of transport of alpha-aminoisobutyric acid (Lieberman et al., '79). We have partially purified the growth-inhibitory proteins from plasma membrane of 3T3 cells. These growth-inhibitory proteins behave as intrinsic membrane proteins and do not require membrane lipids for activity. The partially purified proteins arrest cell growth without affecting the rate of alpha-aminoisobutyric transport; thus, inhibition of both transport and cell growth are not obligatorily coupled events.

Aminoisobutyric Acids↗
PubMed1979

Regulation of the cell cycle of 3T3 cells in culture by a surface membrane-enriched cell fraction.

Addition of a suspension of a surface membrane enriched fraction prepared from confluent 3T3 cells to sparse 3T3 cells in culture results in a concentration dependent and saturable decrease in the rate of DNA synthesis. The inhibition of cell growth by membranes resembles the inhibition of cell growth observed at confluent cell densities by a number of criteria: 1) In both cases the cells are arrested in the G1 portion of the cell cycle; 2) the inhibition by membranes or by high local cell density can to a large extent be compensated for by raising the serum concentration or by addition of fibroblast growth factor plus dexamethasone. Membranes prepared from sparse cultures inhibit less well than membranes from confluent cultures in a manner which suggests that binding of membranes to cells is not by itself sufficient to cause inhibition of cell growth. The inhibitory activity has a subcellular distribution similar to phosphodiesterase (a plasma membrane marker) and appears to reside in one or more intrinsic membrane components. Maximally, membranes can arrest about 40% of the cell population in each cell cycle. Plasma membranes obtained from sparse 3T3 cells are less inhibitory than membranes obtained from confluent cells. This suggests either that the inhibitory component(s) in the plasma membrane responsible for growth inhibition may be in part induced by high cell density, or that this component(s) may be lost from these membranes during purification.

Animals↗
PubMed1979

Growth control by cell to cell contact.

Control of cell growth by cell to cell contact is reviewed with particular emphasis on two systems--contact inhibition of growth observed with Swiss 3T3 cells and the mitogenic stimulation of Schwann cells by dorsal root ganglia neurites. In both cases the biological effect can be reproduced by the addition of surface membranes to the corresponding cells. In the case of contact inhibition of 3T3 cells, biological activity appears to correlate with membrane binding to the cells. An octylglucoside extract of 3T3 plasma membranes retains the biological activity (growth inhibition) of the original membranes.

Aminoisobutyric Acids↗
PubMed1978

Inhibition of growth of 3T3 cells by extract of surface membranes.

The growth of Swiss 3T3 cells can be inhibited by the addition of a plasma membrane enriched fraction from 3T3 cells [Whittenberger, B & Glaser, L. (1977) Proc. Natl. Acad. Sci. USA 74, 2251--2255]. We report conditions for the extraction of the inhibitory components from the membranes with octylglucoside. The solubilized components reversibly inhibit the rate of cell division of 3T3 but not of simian virus 40-transformed 3T3 cells. The inhibitory activity is heat labile and nondialyzable. The inhibition observed with the soluble extract can be reversed by mitogenic factors present in serum.

Cell Division↗
PubMedDate not supplied

The clinical use of multimodality therapy in the management of cancer.

The essential challenge in managing malignant disease with intent of cure is to eradicate the last malignant cell without imposing unacceptable burdens regarding toxicity, functional loss, or damaged cosmesis. In this review we examine the strengths and limitations of surgery, radiotherapy, and systemic chemotherapy when used as single modalities and the unique features of each that allow their advantageous combination. Finally, we consider newer developments in the antineoplastic armamentarium which may soon contribute to the challenges of achieving cure with acceptable sequelae.

Antineoplastic Combined Chemotherapy Protocols↗