Search PubMed⌕ Search

Biomedical subjects

R J Scott

Publications and source records attributed to R J Scott.

At least 127 records · Page 7Linked to original sources
PubMed1987

Response of canine oral carcinomas to heat and radiation.

Thermal enhancement of radiation response improved the probability for local tumor control without increasing the risk for late complications in this study of relatively advanced stage tumors. Thirty-eight dogs with naturally occurring oral carcinomas were randomized to two radiation dose response groups to receive radiation alone or combined with local hyperthermia. Radiation was delivered in 10 fractions over 22 days. Heating was done 3 hours after seven of the radiation doses. The objective was to maintain a minimum tumor temperature of 42 degrees C and a maximum normal tissue temperature of 40 degrees C for 30 minutes. Normal tissue temperatures were usually 40 degrees C or less but there was great heterogeneity in tumor temperatures. Temperatures at tumor margins never exceeded 41.5 degrees C. The TCD50 for radiation was 38 Gy (32-46 Gy, 95% C.I.) and for radiation and heat it was 33 Gy (30-36 Gy, 95% C.I.). The slope of the dose response was much steeper for radiation and heat than for radiation alone indicating that the heterogeneity of tumor response was decreased with heat. All tumors were controlled at 40 and 45 Gy with heat whereas only 57% and 75% were controlled with 40 and 45 Gy radiation only. There were no late necroses for radiation and heat. The tumor control enhancement might be improved with different sequences, number of heatings or other time temperature relationships. It is not possible to predict the optimum treatment scheme because of the lack of knowledge of the influence of hyperthermia on subsequent heat or radiation treatments. That influence could be affected greatly by changes in tumor microcirculation, pH, and oxygenation as well as development and decay of thermotolerance in tumor and normal tissue.

Animals↗
PubMed1987

Attitudes and knowledge of nursing staff in relation to management of postoperative pain.

The effectiveness of pain control following surgery is notoriously difficult to assess, but objective assessment by nursing staff has been found to correlate reasonably well with subjective patient assessment. A study was designed to investigate the attitudes and knowledge of 86 qualified nursing staff in relation to postoperative pain management. Overall knowledge was sound to a point, but there were some obvious deficiencies in practical application; for example, 25% of staff would wait until a patient was in severe pain before using a prescribed (charted) analgesic. Additionally, almost three-quarters of staff felt that, in general, postoperative patients received adequate pain relief, while the great majority felt that prescription writing could be improved, mainly by improved legibility and clarity of actual instructions. The results suggest that the aim of postoperative pain management--that is, the provision of adequate analgesia--may need to be more strongly defined in nursing education.

Analgesics, Opioid↗
PubMed1986

Transfer of antibiotic resistance genes between yeast and mammalian cells under conditions favoring cell fusion.

Antibiotic resistance to G418 has been transferred into Chinese hamster cell lines via a plasmid vector. The same plasmid, which also contained the Leu2 gene, has been used to transform Leu2- yeast (strain MC16) to leucine prototrophy. Subsequent fusion between transformed yeast and untransformed hamster cells demonstrated that plasmid DNA could be transferred and its genes expressed within the mammalian cell genome. The fusion of transformed hamster cells with untransformed MC16 yeast cells demonstrated that DNA integrated within the mammalian cell genome could be transferred to correct the Leu2 deficiency and also confer G418 resistance on some yeast colonies.

Animals↗
PubMed1985

Physiological studies of whole-body hyperthermia of dogs.

Whole body hyperthermia to 42 degrees C was induced in five normal beagles, using a humidity- and temperature-controlled chamber. Core temperatures of 41.2-43.0 degrees C were achieved in 50 min and maintained for 60 min. Cardiopulmonary responses included marked tachypnea and tachycardia. Blood gases underwent progressive drops in both PO2 (mean, 117 torr) and PCO2 (mean, 22 torr), suggesting the possibility of the development of a diffusion barrier during heating. Increased anion gaps in the face of respiratory alkalosis indicated that a metabolic acidosis developed in the heated dogs. Transient but significant drops in serum potassium and phosphorus were also observed during hyperthermia. Other physiological data, including serum chemistries, complete blood count, colony-forming units, and urine electrolyte excretion, did not change significantly.

Animals↗
PubMed1984

The microbiology of selected retail food products with an evaluation of viable counting methods.

In an inter-laboratory survey, the pour plate, surface spread, agar droplet and spiral plate methods were used in parallel with the surface drop method for enumeration of micro-organisms in foods. Good agreement was obtained between all surface methods of enumeration, but there was poor agreement between molten agar methods and the surface drop method. A total of 1143 samples of food that were ready for consumption at the point of retail sale were examined. Eight types of food products were chosen: meat pasties, sausage rolls, real-cream slices, synthetic-cream slices, mayonnaise-based coleslaws, faggots, patés and continental sausages. The results of this survey suggest that the upper limit for an acceptable viable count should vary according to the food product. Salmonellae were not isolated on any occasion. Potentially harmful organisms were not isolated at levels expected to constitute a public health hazard. Information concerning the nature of the product, the total viable count, the presence or absence of pathogenic, toxigenic or indicator organisms, the spectrum of the bacterial flora and the relative predominance of each organism must all be considered when assessing the microbiological acceptability of retail 'ready to eat' products.

Bacillus cereus↗
PubMed1983

Appearance of the liver form of pyruvate kinase in differentiating cultured foetal hepatocytes.

From about the 16th day of gestation three forms of pyruvate kinase are present in foetal rat liver (L, R, and M2). Hepatocytes isolated from 15-day-old foetuses do not possess the liver form of pyruvate kinase, but after three days in culture this enzyme can be detected. No effect on the appearance of the enzyme could be seen by administration of insulin and fructose. Hepatocytes isolated from 19-day-old foetuses exhibit three forms of the enzyme (L, R, and M2) on day 1 of culture but thereafter only two forms are detectable (L and M2). A decrease in activity of the L form is observed. This could be retarded by administration of insulin and fructose.

Animals↗
PubMed1982

Pneumatically powered vertebral displacement device for dogs.

A pneumatically powered trauma device was developed to produce vertebral displacement and spinal cord injury in dogs. After surgical exposure of the spine, displacement was done without laminectomy or cutting of the intervertebral disc. Trauma resulted in luxation between L1 and L2 or fractures of L1 and L2. Force required to cause displacement was recorded via a load sensing system and ranged between 1,848 and 2,666 newtons. In a few dogs, there was partial return of the displaced segment upon pressure release from the device at posttrauma hour 4. The device was an effective means of producing spinal injuries in dogs, and provides a method for studying spinal column and spinal cord injuries.

Animals↗
PubMed1982

Piretanide (HOE 118) in dogs.

Piretanide, a "loop" diuretic, was administered orally and IV at 3 dose levels to healthy Beagles. The effects were measured over an 8-hour period. A marked diuresis occurred with both methods of administration at all dose levels. It was characterized by increased excretion of Na+, Cl-, and, to a lesser extent, K+. Urine osmolality and specific gravity decreased significantly, while urine Na+ and K+ concentrations decreased concurrently. Changes from base lines were not detected in hematologic values, except for serum K+ which reached below base line with larger doses. Piretanide is a potent diuretic and treated patients should be monitored for hypokalemia.

Administration, Oral↗
PubMed1981

Combined pharmacologic and surgical treatments for acute spinal cord trauma.

Acute spinal cord trauma was induced by the Allen method at T12 in 48 dogs. Six groups of 7 dogs each were treated with combinations of pharmacologic and surgical treatments; a 7th group of 6 dogs remained as traumatized nontreated controls. Results indicate an additive therapeutic effect in those patients treated with myelotomy and dimethyl sulfoxide. Dexamethasone, reserpine, and perfusion with hypertonic dextrose solution were of no benefit.

Acute Disease↗
PubMed1980

Phycomycosis: a cause of bronchial obstruction.

A patient with diabetes mellitus presented with an obstructing mycetoma in the right bronchus intermedius due to Phycomycetes. Review of the literature revealed eight prior case reports of patients with prominent endobronchial disease attributable to phycomycosis. Indolent, obstructing lesions in large bronchi were noted in diabetics. The clinical illness differed from the fulminant fungal pneumonia noted in leukemics but was also lethal because of localized complications such as erosion into the pulmonary artery. The differential diagnosis included mucoid impaction, bronchocentric granulomatosis, and mycotic bronchitis. Surgical resection appears to be the appropriate therapy for well localized bronchial lesions.

Airway Obstruction↗
PubMed1978

A comparative study of T-61 and pentobarbital for euthanasia of dogs.

A comparative study of T-61 and double-strength pentobarbital for euthanasia of dogs was performed. Effects on EEG, ECG, arterial blood pressure, and respiration were monitored, and time to collapse was measured. In most respects, the effects of the 2 agents were similar; however, 3 of 12 dogs given pentobarbital resumed respiration and cardiac function. None of 9 dogs given T-61 evidenced signs of recovery.

Amides↗
PubMed1978

Toxoplasmosis.

Explore the source record for details and available documents.

Animals↗
PubMed1976

Physiological data collection system for field use in trained military dogs.

This research program resulted in synthesis of a complete system for "in the field" collection of dynamic physiologic data from trained military dogs. Sensors and sensor implantation techniques were developed for arterial blood pressure, electroencephalogram, electrooculogram, temperature, and respiratory rate monitoring in dogs under strenuous field conditions. A data acquisition system was developed that provided the capability for recording this physiologic data for later computer analysis, and computer programs were written for evaluation of the data. In the final evaluation of the system, two factors indicated a need for additional refinement: (1) that of reducing EEG signal artifact due to cable capacitance and, (2) signal jitter caused by the casette recorder.

Analog-Digital Conversion↗