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T Jamieson

Publications and source records attributed to T Jamieson.

11 recordsLinked to original sources
PubMed1999

Granulocyte macrophage colony-stimulating factor and interleukin-3 regulate chemokine and chemokine receptor expression in bone marrow macrophages.

The beta-chemokine macrophage inflammatory protein-1 alpha (MIP-1alpha) and its associated receptors are involved in the regulation of pro-inflammatory and haemopoietic processes. This study was designed to investigate regulation of expression MIP-1alpha and its receptors by other haemopoietic cytokines. Murine bone marrow macrophages (BMM) were treated with or without GM-CSF or IL-3 and expression of MIP-1alpha, other chemokines and their receptors examined by Northern blotting. Receptor levels were also examined using Scatchard analysis and functional tests. Treatment of BMM with GM-CSF revealed a striking increase in MIP-1alpha mRNA levels, relative to untreated cells with a corresponding increase in MIP-1alpha protein. A similar increase in mRNA levels was found when BMM were treated with IL-3. An increase in the expression of three other beta-chemokines namely MIP-1beta, MCP-1 and MCP-3, was also found following treatment with GM-CSF or IL-3. We have additionally examined the expression of the known beta-chemokine receptors in BMM and observed an increase in CCR1 mRNA levels following treatment with GM-CSF and IL-3, but no change was seen in the level of CCR5 expression. The increase in CCR1 expression was reflected in an increase in the number of cell surface receptors for MIP-1alpha on the GM-CSF treated BMM and in an enhanced response of the GM-CSF treated BMM to CCR1 ligands. These data suggest that GM-CSF and IL-3 may be involved in mechanisms regulating expression levels of MIP-1alpha and its receptors.

Animals↗
PubMed1998

Hemizygosity of the MAX gene locus in HL60 cells.

The oncogenic activity of c-MYC is well known, and genetic aberrations in this locus are associated with a variety of human neoplasms. Because the encoded MYC protein has transcriptional activity only when dimerized with MAX, it is possible that mutations of MAX also could have phenotypic consequences. We have now found, by fluorescence in situ hybridization and quantified Southern blot analyses, that the MAX gene has been reduced to hemizygosity in HL60 cells. Although the sequence of the coding region of the remaining allele of the MAX gene is not mutated, this reduction in gene dosage may be the cause of a lower abundance of MAX protein in these cells that could result in an imbalance in the complex transcription factor network in which MAX has a pivotal role.

Basic Helix-Loop-Helix Leucine Zipper Transcriptio↗
PubMed1993

Cognitive function in hypertension: a community based study.

Cognitive function was investigated in a random sample of subjects on the general practitioners' registry of hypertensive patients in an inner city area and matched with normotensive controls. The response rate was 66% giving 90 matched pairs, average age 63 yrs, with 47% men. There was no difference in educational background or measures of reading ability between the two groups. Cognitive function tests showed a consistent trend of poorer performance in hypertensives, with significant differences in Verbal Learning (immediate recall and retention). Age was inversely related to cognitive function, but no additional deterioration with increasing age was shown in hypertensives.

Adult↗
PubMed1990

Regulation of the relative abundances of c-myc mRNAs in human promyelocytic HL60 cells.

Transcription of the c-myc gene is initiated mainly from two promoters, P1 and P2. By S1 nuclease analysis we found that there is 8 times more P2- than P1-initiated RNA in total RNA from HL60 cells. The half-lives of P1- and P2-initiated transcripts are 26 and 18 min, respectively, so the difference in the relative abundance of the mRNAs is not due to differences in their stabilities. The relative rates of transcription from the P1 and P2 promoters, estimated by in vitro nuclear run-on analysis, were found to differ by about 10-fold, sufficient to account for the difference in the steady-state levels of the two mRNAs. The abundance of c-myc mRNA changes dramatically during differentiation of HL60 cells. Dimethyl sulphoxide causes a very rapid reduction in total c-myc mRNA, while with phorbol ester a transient increase occurs followed by a more gradual decline. At no time during these dramatic alterations were significant changes detected in the relative abundance of P1- and P2-initiated mRNAs, or in their stabilities.

Cell Transformation, Neoplastic↗
PubMed1986

Corticosteroids for rheumatic disease. 1. Physiology, pharmacology, and therapeutic strategies.

Of the corticosteroid preparations available, the intermediate-acting agents are the preparations most commonly used in the rheumatic diseases. Careful tailoring of dosage is important to avoid adrenal atrophy and signs of adrenocortical hypofunction. The best regimen in a given patient depends on the amount of antiinflammatory and immunosuppressive activity required. The therapeutic strategies in use include pulse therapy, daily high-dose therapy, daily low-dose therapy, and alternate-day dosing. The latter two methods are preferable because of the decreased likelihood of adverse reactions, yet are not sufficient in cases of fulminant systemic inflammatory processes.

Adrenal Cortex↗