Regulation of lysyl oxidase expression in lung fibroblasts by transforming growth factor-beta 1 and prostaglandin E2.

The regulation of lysyl oxidase produced by cultured, lipid-enriched, neonatal rat lung fibroblasts was explored. The presence of 40 pM of transforming growth factor-beta 1 (TGF-beta 1) in overnight cultures increased levels of enzyme secreted into the medium by 1.6-fold while steady-state levels of lysyl oxidase mRNA increased similarly.

Retinoic acid-induced inhibition of type I collagen gene expression by human lung fibroblasts.

We examined alpha 1(I) collagen gene expression in all-trans retinoic acid (RA)-treated human lung fibroblast cultures. RA (10(-5)M) decreased steady-state levels for alpha 1(I) collagen mRNA by at least 75% after 24 h. The inhibition was evident within 8 h after addition of RA, was dose dependent and reversible.

Mutant herpes simplex virus induced regression of tumors growing in immunocompetent rats.

Herpes simplex virus (HSV) mutants kill dividing tumor cells but spare non-proliferating, healthy brain tissue and may be useful in developing new treatment strategies for malignant brain tumors. Two HSV mutants, a thymidine kinase deficient virus (TK-) and a ribonucleotide reductase mutant (RR-), killed 7/7 human tumor cell lines in tissue culture. The TK-HSV killed Rat RG2 glioma and W256 carcinoma lines but not the rat C6 glioma in culture.

The effect of retinoic acid on amino acid uptake and protein synthesis by lung fibroblasts.

The effect of retinoic acid (RA) on the uptake and utilization of extracellular amino acids by fetal lung fibroblasts was examined. RA decreased the incorporation of [3H]proline into collagen and other proteins. The effect was maximal at a RA concentration of 10(-5) M; smaller decreases were observed at a RA concentration of 10(-6) M.

Iododeoxyuridine uptake and retention as a measure of tumor growth.

Iodine-131-iododeoxyuridine (IUdR) uptake and retention was measured in two C6 glioma cell lines (C6m and C6a) with different growth characteristics. Animals with intracerebral (i.c.

Kinetics of serum, tear, and corneal antibody responses in resistant and susceptible mice intracorneally infected with Pseudomonas aeruginosa.

The studies described here are aimed at determining the kinetics of antibody responses specific to Pseudomonas aeruginosa ATCC 19660 in sera, tears, and corneas of naturally resistant DBA/2 mice and susceptible C57BL/6 mice after intracorneal infection. Immunoglobulin (IgG) and IgM responses in sera were significantly greater in DBA/2 mice for the first 2 weeks postinfection. Little or no IgA was detected in the sera of mice from either strain.

Serum antibody response to Pseudomonas aeruginosa antigens during corneal infection.

Previous studies in our laboratory have indicated that naturally resistant, inbred DBA/2J mice mount a greater serum antibody response to Pseudomonas aeruginosa 19660 than susceptible C57BL/6J mice. However, the specificity of the antibody produced was not known. The present study examines the specificity and kinetics of the humoral response of these mouse strains to potential virulence factors produced by the organism during both a primary and a secondary corneal infection administered 4 weeks after the primary infection.

Recombinant interleukin-1 beta inhibits elastin formation by a neonatal rat lung fibroblast subtype.

The effect of recombinant interleukin-1 beta (rIL-1 beta) on elastin accumulation by lipid-laden interstitial cells (LIC) derived from neonatal rat lung was examined. The LIC, a fibroblast subtype, synthesized large amounts of elastin which was deposited into the extracellular matrix. This elastin was alkali-resistant and had an amino acid composition typical of adult rat elastin.

Peripheral T cells in diabetes prone (DP) BB rats are CD45R-negative.

Diabetes prone BB (DP BB) rats are known to develop insulin dependent diabetes mellitus. In addition, a number of other immune abnormalities have been observed, like severe T lymphopenia, lack of CD8+ T cells, and lack of RT6+ T cells. Here we report double-labelling studies of lymph node T cells using MRC OX-32 (CD45R), and demonstrate that this T cell subset is absent in young adult DP BB rats.

Cold-induced bronchoconstriction: role of cutaneous reflexes vs. direct airway effects.

To determine the relative contributions of direct airway vs. reflex cutaneous thermal receptor stimulation in cold-induced bronchoconstriction, we isolated these two aspects of cold exposure in 10 asthmatics and 13 normal subjects. Ice packs were applied to the skin of the face, chest, thigh, and upper arm in random sequence while serially measuring specific conductance.

Responses of wild muskrats (Ondatra zibethicus L.) to scented traps.

Free-ranging muskrats were trapped in scented and blank traps in New York State at local ponds during all seasons and at a wildlife refuge in spring and early summer. In a total of 4839 trap-nights, 65 muskrats were caught. Trapping success was 1.

Evaluation of five immunological methods for the assay of serum netilmicin.

Three specific immunological methods for the determination of netilmicin and two enzyme immunoassays for gentamicin were compared for assaying serum netilmicin. The commercial kits we used were Radioimmunoassay (RIA), Substrate Labelled Fluorescence Immunoassay (gentamicin) ( SLFIA ), Homogeneous Enzyme Immunoassay (gentamicin and netilmicin) (EMIT) and Fluorescence Polarization Immunoassay ( FPIA ). After analysing spiked calf serum samples in the range of 0-15.

A Computer Program for a Trilinear Diagram Plot and Analysis of Water Mixing Systems.

The Piper (1953) trilinear diagram has been widely used to graphically represent the dissolved constituents of natural waters and to test for apparent mixtures of waters from different sources. Because of the time required to plot points and calculate the proportional values of mixing, this treatment of data was often quite tedious, particularly in studies involving large numbers of chemical analyses. The PIPER program was written in BASIC to be run on a Hewlett-Packard desktop computer with an X-Y plotter.

The cardiovascular action of oxygen breathing: effect on adrenergic stimulation.

20 anesthetized mechanically ventilated dogs received an infusion of epinephrine, 2 micrograms/kg/min, for 4 h. 10 dogs were ventilated with air for the entire 4-hour period and 10 were ventilated with oxygen for the first hour and then air for 3 h. During the first hour of the epinephrine infusion in the group ventilated with oxygen, as compared to the group ventilated with air, the heart rate decreased (it increased in the dogs ventilated with air); the cardiac output increased less; the systemic vascular resistance decreased less; the pulmonary vascular resistance decreased more; and the pulmonary artery wedge pressure increased (it decreased in the dogs ventilated with air).