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Biomedical subjects

A T Taylor

Publications and source records attributed to A T Taylor.

At least 55 records · Page 3Linked to original sources
PubMed1985

Gallium-67 citrate imaging in underground coal miners.

Twenty-two underground coal workers with 27 or more years of coal dust exposure were studied with gallium-67 citrate (Ga-67) imaging. Radiographic evidence of coal workers pneumoconiosis (CWP) was present in 12 subjects. The Ga-67 scan was abnormal in 11 of 12 with, and 9 of 10 without, CWP. The Ga-67 uptake index was significantly correlated with total dust exposure (p less than 0.01) and approached significant correlation with the radiographic profusion of the nodules (0.10 greater than p greater than 0.05). There was no correlation between Ga-67 uptake and spirometric function, which was normal in this group of patients; furthermore, increased lung uptake of gallium did not indicate a poor prognosis in subjects no longer exposed to coal dust. While coal dust exposure may be associated with positive Ga-67 lung scan in coal miners with many years of coal dust exposure, the scan provided no information not already available from a careful exposure history and a chest radiograph. Since Ga-67 scanning is a relatively expensive procedure we would recommend that its use in subjects with asymptomatic CWP be limited to an investigative role and not be made part of a routine evaluation.

Aged↗
PubMed1985

Gastric emptying measurements: delayed and complex emptying patterns without appropriate correction.

Anteriorly acquired and geometric mean corrected gastric emptying curves of solids and liquid isotopic-labeled meals were compared in 37 subjects given 61 meals of three different sizes. Anterior data alone consistently and significantly underestimated solid-phase gastric emptying rates with all meal sizes when compared to geometric mean acquired data. However, with liquids there were only slight differences between anterior and anterior and posterior geometric mean corrected emptying-rates. The difference probably reflects greater attenuation of the 140 kev photon of 99mTc compared to the 247 keV photon of 111In. With anterior data alone, an apparent early delay in emptying of solids was present with all meal sizes and the resultant emptying curves were nonlinear in shape. Geometric mean correction resulted in the linearization of the solid-phase emptying curves and essentially eliminated the apparent delay in emptying or lag phase noted with the anterior data alone. Based on our results, geometric mean correction techniques are necessary for accurate assessment of radioisotopic-labeled solid meals.

Adult↗
PubMed1984

Comparative effects of diltiazem, propranolol, and placebo on exercise performance using radionuclide ventriculography in patients with symptomatic coronary artery disease: results of a double-blind, randomized, crossover study.

The effects of oral diltiazem (120 mg), propranolol (100 mg), and placebo on exercise performance and left ventricular function were compared before and during symptom-limited supine bicycle exercise by means of multigated radionuclide ventriculography in 12 patients with documented, symptomatic coronary artery disease; a double-blind, randomized crossover protocol was used. Diltiazem increased ejection fraction (EF) at submaximal exercise (+7.0 absolute percentage points, p less than 0.02) and maximal exercise (+8.1 percentage points, p less than 0.01). Exercise EF was increased by 13.6 percentage points (p less than 0.02) in patients with decreased ventricular function (resting EF less than 50%). Propranolol had no effect on exercise EF at any stage, even when patients with EF less than 50% were excluded. The increase in total exercise time was significant after diltiazem (+27%, p less than 0.01) but not after propranolol (+16%, p = NS). As expected, propranolol decreased both resting (-9 bpm, p less than 0.01) and exercise heart rates (-27 bpm, p less than 0.001), whereas diltiazem had no significant effect. Propranolol decreased resting diastolic blood pressure (-8 mm Hg, p less than 0.02), exercise systolic (-27 mm Hg, p less than 0.001) and diastolic (-9 mm Hg, p less than 0.01) blood pressures, and rest (p less than 0.01) and exercise (p less than 0.001) double product. Diltiazem decreased resting systolic blood pressure (-9 mm Hg, p less than 0.01) and both resting (-8 mm Hg, p less than 0.001) and exercise (-9 mm Hg, p less than 0.01) diastolic blood pressures.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1984

Pulmonary uptake in indium-111 leukocyte imaging: clinical significance in patients with suspected occult infections.

A retrospective review was undertaken to evaluate the frequency and significance of pulmonary activity noted on 306 indium-111 leukocyte studies involving 232 patients with suspected occult infections. Forty-eight studies showed pulmonary activity in one of two patterns of uptake, focal or diffuse. Fourteen of 27 studies (52%) with focal uptake and two of 21 studies (10%) with diffuse uptake were associated with infectious processes. Lung uptake of indium-111-labeled leukocytes was a poor predictor of pulmonary infection in patients studied for occult infection, although the focal pattern was more likely than the diffuse pattern to be associated with infection.

Adolescent↗
PubMed1984

Chemical carcinogenicity and the antineoplastic agents.

The subject of chemical carcinogenicity is reviewed with discussions of the involved environmental factors, proposed mechanisms of mutagenesis and carcinogenesis, dose-response considerations, secondary tumor development, and an emphasis on the potential carcinogenicity of antineoplastic agents. Although the causes of various cancers are complex, 70-90% of human cancers are thought to be caused by environmental factors. The factors that have been strongly implicated are excessive cigarette use, heavy alcohol consumption, and disordered dietary practices. Of the minor possible causes of cancer, the administration of prescribed pharmaceutical agents such as the antineoplastic drugs accounts for a suspected 1% of total cancer deaths in the United States. Chemical carcinogenesis involves a multistep process of initiation, promotion, and progression. The development of cancer in man usually takes several years and may be associated with specific tissue susceptibility. Although antineoplastic agents have been recognized for their potential ability to cause cancer, it is difficult to assess from the literature their actual carcinogenic effects in man. Important determinants that modify the ability of the host to deal with carcinogenic substances and the subsequent effects have not been fully evaluated. The control of chemical carcinogenesis must involve reduction of exposure to potential hazards wherever possible. To reduce the risks involved in handling antineoplastic agents, health-care professionals should follow a method of systematic avoidance by adhering to appropriate procedures.

Animals↗
PubMed1983

Lack of influence of commonly used drugs on bioassay indicator organisms.

Many commonly used pharmaceutical agents have been found to inhibit bacterial growth in vitro. Determinations of antimicrobial concentrations in sera of patients taking nonrecognized antibacterial agents could possibly be altered if bioassay systems are utilized for the determinations. We therefore attempted to determine the in vitro effect of commonly used drugs on bioassay indicator organisms. Fifty-one different agents (antihistamines, anticholinergics, central nervous system agents, cardiovascular agents, analgesics, steroids, muscle blockers, and other miscellaneous agents) were tested for inhibition or enhancement of the growth of Bacillus subtilis, Staphylococcus aureus, Micrococcus luteus, and Klebsiella pneumoniae. None of the agents tested exhibited any effect on standard in vitro bioassay organisms. Nortriptyline hydrochloride inhibited the growth of B. subtilis and M. luteus at a concentration of 500 micrograms/ml (zones of inhibition, 14 and 13 mm, respectively), but no inhibition was observed with concentrations of 50 micrograms/ml or lower.

Bacteria↗
PubMed1983

Computer-assisted versus visual lung gallium-67 index in normal subjects and in patients with interstitial lung disorders.

The pulmonary uptake of 87Ga citrate has been proposed as an index that assists clinical decision-making in patients with certain interstitial lung diseases. Such use, however, requires definition of the range of normal values, the range of values in patients with various interstitial diseases, and interobserver and intraobserver variability. We studied 9 normal subjects and 15 patients with interstitial lung diseases. The 87Ga indexes were determined by visual analysis and by a computer-assisted method. We found that the variation among experienced observers in visual index values was substantial in both normal subjects and patients, and that the computer-assisted indexes were less variable. These data suggest that if this approach is to be used in clinical decision-making: (1) the variability of visual indexes, and of normal values, should be recognized; (2) consideration should be given to a less subjective, computer-assisted method of index calculation; (3) each institution should establish standardized methodology and consider determination of its range of variability and normal index values.

Adult↗
PubMed1983

Treatment of L-asparaginase allergic reaction.

The treatment of an allergic reaction to L-asparaginase is discussed in the presentation of a case of a 26-year-old man with chronic myelogenous leukemia who was undergoing methotrexate-L-asparaginase rescue therapy. The possible mechanism of action of L-asparaginase is reviewed, and precautions for use of L-asparaginase in combination therapy with methotrexate are presented.

Adult↗
PubMed1982

A difficult monitoring situation: theophylline toxicity.

The author discusses the mishandling of drugs as one of the difficulties of monitoring serum theophylline levels, citing the case of a 68-year-old woman with long-standing chronic obstructive pulmonary disease, in whom the first three days of aminophylline therapy were prescribed and administered in a manner inconsistent with policy and procedure. The need for pharmacists to participate actively in clinical practice and patient care is stressed.

Aged↗
PubMed1982

Failure to detect extramedullary hematopoiesis during bone-marrow imaging with indium-111 or technetium-99m sulfur colloid.

A patient with postpolycythemic myeloid metaplasia developed an enlarging abdominal mass documented on TCT scanning. To distinguish between lymphoma and extramedullary hematopoiesis, marrow elements were imaged with indium-111 chloride and technetium-99m sulfur colloid. Because the mass failed to accumulate either tracer, a presumptive diagnosis of lymphoma was made and exploratory surgery was performed. The excised mass was found to consist of enlarged lymph nodes containing extramedullary hematopoiesis. Caution should be exercised in the use of In-111 or Tc-99m SC bone-marrow scans to diagnose sites of extramedullary hematopoiesis.

Bone Marrow↗
PubMed1981

Physical assessment series: the thorax and the lungs.

The anatomy of the thorax and lungs and the physiology or respiration are complex. The physical assessment techniques which, on the surface, appear relatively easy to master, require hours of practice of observation, palpation, percussion, and auscultation before the examiner becomes familiar with the more subtle changes of disease process and the wide variations of normal that may be confused with illness. These are skills that may be quickly lost if not regularly applied. But perhaps with the use of such techniques, the pharmacist can play an even greater role in the monitoring of drug therapy.

Adult↗
PubMed1980

Physician acceptance of clinical pharmacy service in a skilled nursing home.

A study was made of physician acceptance of pharmacist-recommended changes in the drug therapy of elderly institutionalized patients. The records of 92 such patients were reviewed by the pharmacist. In 33 instances the pharmacist recommended changes in drug therapy. In 75.8% (25 of these 33 patients) the recommendations were judged appropriate and were accepted by the physician concerned.

Aged↗
PubMed1977

Multiorgan scans for staging lung cancer. Correlation with clinical evaluation.

One hundred consecutive patients with findings suggestive of resectable bronchogenic carcinoma were studied prospectively to determine if routine liver, brain, and bone scans (multiorgan scans) detected metastases which were not suggested by a history, physical examination, and serum chemistries. Multiorgan scans were compared with clinical evaluations in 52 patients found to have operable bronchogenic carcinoma. There was a discordance between scans and clinical evaluations in 25/153 scans (16 per cent). Two of the 22 negative scans in patients with abnormal clinical findings were false negative. Sixteen of the 17 positive scans in patients with normal clinical findings were false positive. One of the 131 scans done in patients with no evidence of metastases on clinical evaluation was true positive. These data indicate that the routine use of multiorgan scans in the initial staging of potentially resectable bronchogenic carcinoma is not justified.

Bone Neoplasms↗
PubMed1976

Intestinal concentration of 99mTc-pertechnetate into isolated loops of rat bowel.

In scanning patients for Meckel's diverticulum, the colon occasionally visualizes more rapidly than would be expected simply from gastric secretion and intestinal transit. To gain a better understanding of the intestinal physiology of pertechnetate and thereby to make a more intelligent interpretation of abdominal scans, segments of the gastrointestinal tract of Sprague-Dawley rats were isolated by transection between double ligations. After abdominal closure, the animals received an intravenous injection of 99mTcO4 and were killed at 30, 45, or 150 min after injection. Technetium concentrations in the stomach, colon, and appendiceal contents increased significantly with time after dosing, and after 30 min technetium could be clearly imaged in the stomach, upper small intestine, appendix, and colon. These results suggest that technetium is actively secreted by the intestinal mucosa. Additionally, the results indicate caution in the interpretation of scans in patients with suspected Meckel's diverticulum since, in the rat and probably in the human, significant amounts of technetium can accumulate in the gut apart from gastric secretion and intestinal transit.

Animals↗