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Biomedical subjects

V MacLeod

Publications and source records attributed to V MacLeod.

7 recordsLinked to original sources
PubMed2000

Molecular cloning and functional characterization of a vasotocin receptor subtype that is expressed in the shell gland and brain of the domestic chicken.

In chickens, oviposition is correlated with increased plasma levels of the neurohypophysial hormone vasotocin, and vasotocin stimulates contraction of uterine strips in vitro. A gene encoding a vasotocin receptor subtype that we have designated the VT1 receptor was cloned from the domestic chicken. The open reading frame encodes a 370-amino acid polypeptide that displays seven segments of hydrophobic amino acids, typical of guanine nucleotide-protein-coupled receptors. Other structural features of the VT1 receptor include two potential N-linked glycosylation sites in the extracellular N-terminal region, a conserved aspartic acid in transmembrane domain 2 that is found in nearly all guanine nucleotide-protein-coupled receptors, and two potential protein kinase C phosphorylation sites in the third intracellular loop and C-terminal tail. Expressed VT1 receptors in COS7 cells bind neurohypophysial hormones with the following rank order of potency: vasotocin congruent with vasopressin > oxytocin congruent with mesotocin > isotocin. In addition, the expressed VT1 receptor mediates vasotocin-induced phosphatidylinositol turnover and Ca(2+) mobilization. In the chicken, expression of VT1 receptor gene transcripts is limited to the shell gland (uterus) and the brain. Thus, the VT1 receptor that we have cloned may mediate contractions of the shell gland during oviposition and activate reproductive behaviors known to be stimulated by vasotocin in lower vertebrates.

Amino Acid Sequence↗
PubMed1997

Evidence for alternative splicing in hepatic alpha 1B-adrenergic receptor gene expression.

The interactions of catecholamines with alpha 1B-adrenergic receptors (alpha 1B-AR) located on the surface of many cell types are responsible for physiologic and pathologic functions in mammalian systems. Transcription of the alpha 1B-AR gene leads to the expression of multiple alpha 1B-AR mRNAs that are distributed in a tissue-specific fashion. The purpose of this study was to define the 5'-untranslated regions of the multiple alpha 1B-AR gene transcripts. Evidence for a previously unidentified intron in the alpha 1B-AR gene upstream of the receptor open reading frame was obtained via rapid amplification of cDNA ends. A product was amplified and was found to be missing the nucleotide interval from -708 to -194, (+1 is the start of translation). Evidence for tissue-specific alternative intron splicing was obtained from ribonuclease protection assays and RT-PCR experiments. Using an RNA probe extending from -240 to +93 and including 45 nucleotides into the putative intron, a single protected fragment was detected in heart RNA while two protected fragments were detected in liver RNA. RT-PCR amplification of the region spanning the intron resulted in detection of two PCR products in liver RNA and no detectable product in heart RNA. These findings emphasize the complexity of alpha 1B-AR gene regulation and suggest that multiple alpha 1B-AR mRNAs with different 5'-UTRs may play a role in regulating alpha 1B-adrenergic responsiveness.

Alternative Splicing↗
PubMed1989

Brain interleukin 1 and S-100 immunoreactivity are elevated in Down syndrome and Alzheimer disease.

Interleukin 1, an immune response-generated cytokine that stimulates astrocyte proliferation and reactivity (astrogliosis), was present in up to 30 times as many glial cells in tissue sections of brain from patients with Down syndrome and Alzheimer disease compared with age-matched control subjects. Most interleukin 1-immunoreactive glia in Down syndrome and Alzheimer disease were classified as microglia. The number of interleukin 1 immunoreactive neurons did not appear to differ in Down syndrome and Alzheimer disease compared with control brain. Numerous temporal lobe astrocytes in Alzheimer disease and postnatal Down syndrome were intensely interleukin 1-, S-100-, and glial fibrillary acidic protein-immunoreactive and had reactive structure. Interleukin 1 levels in Alzheimer disease temporal lobe homogenates were elevated, as were the levels of S-100 and glial fibrillary acidic protein, two proteins reportedly elevated in reactive astrocytes. These data suggest that increased expression of S-100 in Down syndrome, resulting from duplication of the gene on chromosome 21 that encodes the beta subunit of S-100, may be augmented by elevation of interleukin 1. As a corollary, the astrogliosis in Alzheimer disease may be promoted by elevation of interleukin 1.

Adult↗
PubMed1985

Comparing acuity among hospitals. Who has the sickest patients?

A method by which nursing managers can determine the acuity level of their hospitals' patients, relative to other hospitals, is proposed. Without this information, it is difficult to justify higher staffing needs based on a sicker patient population than other hospitals.

Costs and Cost Analysis↗
PubMed1980

Nurse staffing studies: no need to reinvent the wheel.

The authors estimate that hospitals spend $15,000,000 yearly on nurse staffing studies. Unfortunately, much of this annual investment is used to reinvent the wheel. Therefore, this article recommends standardizing the terminology and some of the basic principles for patient classification (the basis of nurse staffing systems) so that directors of nursing can better assess their organizations and make meaningful comparisons with other institutions. This article is adapted from a presentation at the annual meeting of the Hospital Management Systems Society, Tucson, Arizona, February 15, 1979.

Classification↗