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R Mullins

Publications and source records attributed to R Mullins.

47 records · Page 3Linked to original sources
PubMed1983

Effect of Fluosol-DA on radioimmunoassay results.

Fluosol-DA, an emulsion of perfluorocarbons, is used as a blood substitute. Its presence in samples affects results of certain radioimmunoassays routinely done in our laboratory. In several, added Fluosol-DA caused an upward displacement of the standard curve, the extent of which depended on the structure and quantity of the assayed antigen, the concentration of Fluosol-DA, and the nature of the immunoreagents. Fluosol-DA markedly affected results of assays for triiodothyronine, thyroxin, and digoxin (by one method), but assays for aminoglycosides and protein hormones were unaffected. We determined that Fluosol-DA interacts with unbound labeled (and, presumably, with unlabeled) antigen to form a complex that coprecipitates with the bound antigen-antibody fraction during the separation step. In comparison with the idealized condition we observed an apparent increase in antibody-bound labeled antigen and consequently an apparent underestimation of the measured antigen. Depending on the nature of the immunoreagents, antibodies can extract more or less of their respective antigens from particles of Fluosol-DA emulsion.

Antigen-Antibody Complex↗
PubMed1982

Blood viscosity, glycaemic control and retinopathy in insulin-dependent diabetes.

1. In a cross-sectional study, 32 insulin-treated diabetic patients had elevated low shear (27.1 vs 22.1 mPa s, P less than 0.05) and high shear blood compared with 10 non-diabetic controls. After correction to 45% packed cell volume, the abnormality had a tendency to be greater in patients with proliferative (mean low shear viscosity, 30.8 mPa s) than background (29.2 mPa s) or nil/minimal retinopathy (27.6 mPa s, 0.05 less than P less than 0.97, permutational trend test). 2. The fibrinogen levels were higher in the diabetic group (P less than 0.05) and correlated with the low shear blood viscosity (rs = 0.38, P less than 0.05). 3. In a prospective study, 74 insulin-treated diabetic patients with background retinopathy were randomized into two groups. Thirty-six patients were on attempted improved therapy (A group); in these the mean glycosylated haemoglobin (Hb A1c) fell within 1 year (11.6 to 10.1%, P less than 0.001). both the corrected low shear blood and plasma viscosity fell similarly (P less than 0.001). The fall was greater than in those patients who were kept on usual therapy (U group) and whose glycosylated haemoglobin did not change significantly (11.7 to 11.4% over the year. 4. The effect of diabetes on blood viscosity may not be a direct pathological factor, as the same increased viscosity would be produced by a mean increase of 1.7% in packed cell volume, compared with a population range of 14% packed cell volume.

Adult↗
PubMed1976

Renal prostaglandin synthesis in hypertension induced by deoxycorticosterone and sodium chloride in the rat.

1. The role of renal medullary prostaglandin E has been examined in rats with hypertension induced by sodium chloride and deoxycorticosterone (salt-DOC). 2. Synthesis of prostaglandin E was normal in early salt-DOC hypertension. Indomethacin exacerbated the hypertension, and depressed synthesis of prostaglandin E equally in hypertensive and control rats. 3. Synthesis of prostaglandin E was depressed in rats with late salt-DOC hypertension. 4. The results lend support to the concept that prostaglandin E is involved in the regulation of arterial pressure.

Animals↗
PubMedDate not supplied

Six-year results of annual colonoscopy after resection of colorectal cancer.

Colonoscopy is an important diagnostic and therapeutic tool that may also be useful in the surveillance of patients after curative resection of colorectal cancer. The yield of colonoscopy and the frequency with which it should be performed after operation, however, have not been clearly defined. Over the past 10 years, we have examined these patients annually with colonoscopy or barium enema. This study evaluates the results of a specifically designed protocol that followed 174 patients. Counting all sites, colorectal cancer recurred in 57 of 174 patients, three-quarters within the first 24 months. Nine anastomotic recurrences were detected in the 12-30 month interval; none was reoperated for cure; however, 4 metachronous colon cancers were found and resected for cure. In addition, 30 polyps larger than 1 cm in size and 7 villous adenomas were removed in 30 patients. Combined, these findings represent an interval yield of 3-5% per year. Based on these results and other reports, we recommend that patients undergo colonoscopy annually at least for the first 6 years postresection of colorectal cancer. The detection of new primary tumors and possibly predisposing lesions becomes more important in these patients than detection and cure of recurrent disease.

Colonoscopy↗
PubMedDate not supplied

Clinic- rather than self-monitoring of home blood samples: relevance of day-to-day variability to decision making.

The day-to-day variability of blood glucose concentrations in juvenile diabetes means that it is often more reasonable to aim to achieve a generally good pattern of blood glucose control, rather than regularly to assess the next insulin dose after each blood glucose measurement. This means that immediate assessment by the patient of his blood glucose concentrations is not always necessary. We have investigated control in 22 insulin-requiring diabetic patients by means of a monthly series of four blood samples taken during a day into collector bottles and transported to a laboratory for blood glucose assay. The overall means before breakfast, before lunch, before dinner, and before bed were 6.1, 5.8, 7.3, and 7.2 mmol/L, respectively. In many patients, sufficiently good control can be obtained by this method so that it is not necessary to ask them to measure their own blood glucose concentrations or to ask them to obtain the fairly expensive meters for reading glucose oxidase strips. Control would then probably be best assessed by a series of three daily profiles taken once per month, with, if necessary, the results being discussed with the patient. On the other hand, in more unstable diabetes, home assessment by patients of blood glucose measurements is indicated.

Blood Glucose↗