Search PubMed⌕ Search

Biomedical subjects

D Irwin

Publications and source records attributed to D Irwin.

71 records · Page 4Linked to original sources
PubMed1979

A comparision of normal submaxillary gland proteins with proteins obtained from a transplantable murine salivary gland carcinoma (myoepithelioma).

A new transplantable murine salivary gland carcinoma (myoepithelioma) was further characterized by comparing total protein patterns with normal submaxillary gland proteins. Analysis by isoelectric focussing or by labelling studies with radioactive leucine showed considerable differences between tumour and normal proteins. In contrast, analysis of staining patterns after electrophoresis in sodium dodecyl sulphate containing gels revealed a striking similarity between normal proteins, tumour proteins and proteins obtained from metastatic growths. It thus appears that tumour proteins closely resemble the normal proteins from the tissue of origin with respect to molecular size as determined by electrophoretic mobility, while significant differences occur in charge and labelling kinetics.

Animals↗
PubMed1979

Alterations in the relative abundance of specific messenger ribonucleoproteins associated with compensatory renal hypertrophy.

A possible role of messenger RNA (mRNA)-associated proteins during compensatory renal hypertrophy in modulation of mRNA biogenesis has been examined in this investigation. Renal cytoplasmic free messenger ribonucleoprotein (CF mRNP) and polysomal mRNP (PA mRNP) have been isolated from kidney following 48 hours of compensatory renal hypertrophy, and the relative amounts of proteins associated with CF mRNP and PA mRNP in control and hypertrophying mouse kidney are compared. (CF mRNP refers to nonpolysomal messenger ribonucleoprotein found in the subribosomal region of sucrose gradients. PA mRNP or polysome-associated mRNP refers to mRNP released from polysomes.) CF mRNP has a buoyant density of 1.3 to 1.44 gm. per ml., contains RNA that sediments at 5 to 22 Svedberg units, and has a protein moiety comprising at least 15 polypeptides as revealed by sodium dodecyl sulfate polyacrylamide gels. PA mRNP contains three major polypeptides (molecular weights, 77,000, 52,000 and 17,000). Following 48 hours of compensatory renal hypertrophy, the relative amounts of proteins are changed: a 44,000- and 52,000- molecular weight polypeptide in CF mRNP is increased, a 52,000-molecular weight polypeptide in PA mRNP is reduced, and a 17,000-molecular weight polypeptide in PA mRNP is increased.

Animals↗
PubMed1978

The growth kinetics of synovial fibroblastic cells from inflammatory and noninflammatory arthropathies.

The growth kinetics of subcultured human synovial fibroblasts from 16 patients with inflammatory and noninflammatory arthropathies were studied in antibiotic free media. The experimental design allowed a clear distinction between the growth rates and final saturation densities achieved. The effects of refeeding and of the serum concentration were evaluated for each line. Inflammatory lines achieved significantly higher final saturation densities and growth rates than noninflammatory lines for most protocols, but the differences between rheumatoid and nonrheumatoid groups were less marked. Inflammaroty fibroblasts demonstrated a greater independence to nutritional and growth stimulatory factors in their microenvironment than noninflammatory fibroblasts.

Arthritis, Rheumatoid↗
PubMed1977

Ribosomal proteins of mouse kidney: normal status and during compensatory renal hypertrophy.

Ribosomes were isolated from normal and growing kidney and the protein complement was examined by a two-dimensional gel electrophoretic procedure. Proteins were resolved in the first dimension on the basis of charge and, in the second dimension, on the basis of molecular weight. 60S and 40S ribosomal subunits from normal kidney contained respectively 42 and 31 proteins. 80S ribosomes contained 23 proteins not found with either sub-unit. Nineteen of these proteins were removed from the ribosomes when isolated ribosomes were washed in a high salt buffer. Six proteins of the 80S ribosome corresponded to proteins associated with both sub-units. 80S ribosomal proteins were also studied during compensatory renal hypertrophy after 4-96 h of induced growth. The protein complement displayed by electrophoresis was identical to the pattern seen from normal renal cells.

Animals↗
PubMed1977

Serum immunoglobulin levels in neonatal lambs.

The serum immunoglobulin levels of lambs were monitored 24 h post partum using the zinc sulphate turbidity test. There was a wide distribution in the level of circulating maternal immunoglobulin and quite a large proportion of lambs were hypogammaglobulinaemic. Mean levels were highest in single lambs and lowest in triplets.

Animals↗
PubMed1975

Messenger ribonucleoprotein complexes isolated with oligo(dT)-cellulose chromatography from kidney polysomes.

As an initial step towards understanding the role of mRNP complexes in translational regulation during compensatory renal hypertrophy, characteristics of polysome-associated mRNP isolated by affinity chromatography were studied. Renal mRNP contained 15-30 percent of the counts after a 1 hr pulse with -3H-orotic acid; it sedimented mainly between 10S and 100S and had a buoyant density of 1.42-1.44 g/cm-3. RNA derived from the mRNP sedimented between 5S and 40S on sucrose density gradients, with the greatest radioactivity in the region of 15S. After labeling with -3H-adenine for 1 hr, up to 17 percent of the radioactivity present in the mRNP-associated RNA was resistant to digestion by pancreatic and T1 ribonucleases. The mRNP protein moiety contained six polypeptides with molecular weights 69,000, 75,000, 80,000, 100,000, 109,000, and 118,000 daltons, which were undetected in the material not binding to oligo(dT)-cellulose.

Animals↗
PubMed1975

Cell surface sialoglycopeptide metabolism and surface glycosyl transferase activity in the Ehrlich ascites cell.

1. The in vivo incorporation of radioactivity from [3H]glucosamine into a trypsin labile, cell surface sialoglycopeptide fraction (SGP) of Ehrlich ascites cells was studied in the presence and absence of puromycin pretreatment. The results indicated a much more complete inhibition of incorporation into the surface SGP than in the average intracellular acid insoluble glycoproteins. No evidence of turnover of the carbohydrate portion of the surface SGP independent of protein synthesis could be obtained. 2. However, when intact cells were incubated with labelled uridine 5'-diphosphate-N-actely glucosamine or cytidine 5'-monophosphate (CMP)-sialic acid there was some incorporation largely into acid insoluble material, suggesting the presence of glycosyl transferase activity in the surface. Further evidence for surface activity was obtained when neuraminidase pretreatment of intact cells stimulated incorporation of labelled CMP-sialic acid sixfold and almost all of the incorporated counts could be released by subsequent neuraminidase treatment. Furthermore, a much greater proportion of the incorporated counts could be released by papain than by trypsin treatment of the intact cells. These results suggest that the surface acceptor for exogenously added CMP-sialic acid is not identical to the endogenously synthesized trypsin labile surface SGP.

Animals↗
PubMedDate not supplied

Depot medroxyprogesterone. Management of side-effects commonly associated with its contraceptive use.

Depot medroxyprogesterone acetate is one of the most popular, effective methods of contraception used in the United States. Many women experience unpleasant side effects from this method, including episodic vaginal bleeding, hair loss, depression, and weight gain. This Clinical Practice Exchange describes the treatment strategies for these side-effects used by nurse-midwives from a variety of settings and locales. Contraceptive use can be more acceptable for many women if they are better able to cope with unpleasant side effects of the method. This Clinical Practice Exchange provides knowledge to enhance client coping.

Adaptation, Psychological↗
PubMedDate not supplied

The influence of case mix, site selection, and methods biases on costs of hospitalization for acute exacerbations of chronic obstructive airways disease and lower respiratory tract infections.

OBJECTIVE: To compare costs of hospitalization for lower respiratory tract infection (LRTI) in patients who received antibiotics before admission to those who did not, and in patients with and without underlying chronic obstructive airways disease (COAD) or diabetes mellitus. METHODS: All hospitalizations in a population of 366,849 residents in Tayside Scotland from 1993 to 1994 were analyzed. Three groups of patients were identified by primary discharge diagnosis in 1993/94 and previous admissions from 1980 to 1992: 1) acute exacerbation of COAD; 2) LRTI plus a secondary diagnosis of COAD or previous admission with COAD; 3) LRTI but no secondary COAD or previous admission with COAD. Setting specific costs were applied (e.g., general medicine, intensive care, geriatrics). Dispensed antibiotic prescribing in the 28 days before admission was identified from all community pharmacies. Nonparametric statistical tests were used. RESULTS: Patients with COAD were more likely to have received antibiotics before admission: COAD (n = 893) 49%; COAD + LRTI (n = 316) 43%; LRTI only (n = 822) 33%. Patients who received antibiotics before admission had lower hospital costs than patients who did not. Mean total costs per admission: COAD pound1604 versus pound1625 (p = .5); COAD + LRTI pound2281 versus pound2297 (p = .5); LRTI only pound2365 versus pound3233; (p = .009). Increasing age and diabetes mellitus were associated with higher hospital costs in all three groups. CONCLUSION: Economic models of the value of preventing hospital admissions for COAD or LRTI will be subject to case mix bias unless they adjust for age, community antibiotic use, and comorbidity.

Journal Article↗