Search PubMed⌕ Search

Biomedical subjects

R F Taylor

Publications and source records attributed to R F Taylor.

At least 91 records · Page 5Linked to original sources
PubMed1977

Late recurrence of cancer in the larynx and hypopharynx after irradiation.

11 cases of recurrent laryngeal or hypopharyngeal carcinoma, occurring 5 or more years after radiotherapy for carcinoma, are reported. The possible pathological mechanisms involved include persistence of the original carcinoma, second primary due to the original factors, and radiation-induced carcinoma. The last-mentioned possibility is of vital importance and requires further investigation. If radiation-induced carcinoma is as common as some recent series suggest, then primary treatment of T1 laryngeal carcinoma must be re-thought. However, this author believes that convincing evidence is lacking that irradiation is a common cause of late recurrent carcinoma.

Adult↗
PubMed1977

An outbreak of toxoplasmosis in wallaroos (Macropus robustus) in a California zoo.

Four wallaroos (Macropus robustus) from a central California zoo colony of 22 died within a three week period. Histopathologic findings in all four cases were suggestive of toxoplasmosis. Brain, lung and heart were the most frequently involved organs. Within 4 months of the last death sera from nine colony members were tested for antibodies against Toxoplasma gondii using the indirect hemagglutination test. All nine had serological titers ranging from 1:64 to 1:131,072.

Animals↗
PubMed1977

Feline brain abscesses due to Cladosporium trichoides.

Cladosporium trichoides was isolated from brain abscesses of two cats. No obvious route of entry was found in either case. The brain was the only organ cultured. No other significant lesions were observed during necropsy. These are the first reported cases of such infection in animals.

Animals↗
PubMed1976

Coarctation of the aorta in adults.

Thirty-six patients, 19 men and 17 women, presented at age 18 or older between 1952 and 1974 with coarctation of the aorta. Of the 14 (39%) who had associated cardiovascular disease, 12 had aortic stenosis or insufficiency or both. Three patients had infections-two, endocarditis (aortic valve) and one, endarteritis. Three of the seven patients who did not undergo an operation are alive, two at more than 50 years of age. Five patients had myocardial infarctions, two at 35 years of age. Twenty-nine (80%) had operations; in eight instances the patient was over age 40. All 18 patients undergoing repair of isolated coarctation survived, while only 7 of the 11 patients with associated cardiovascular lesions who underwent repair recovered. Aortic valvular disease and myocardial infarction are serious complicating factors in coarctation of the aorta.

Adolescent↗
PubMed1976

The influence of culture conditions on carotenogenesis in Streptococcus faecium UNH564P.

The growth of Streptococcus faecium UNH564P and its production of triterpenoid carotenoids under a variety of culture conditions were examined. Total extractable cell lipid and carotenoid levels increased with culture age and paralleled the growth curve of the bacterium. Variations of the medium glucose concentration produced significant changes in both cell growth and carotenoid production, with the xanthophyll content decreasing at high glucose concentrations. Carotenoid degradation products were found in highly aerated cultures although a high glucose concentration appeared to have a sparing effect on oxidative degradation. Culture age appeared to have little effect on carotene:xanthophyll ratios. The significance of the production of total and individual carotenoids under the various culture conditions is discussed and related to a postulated scheme of triterpenoid carotenoid biosynthesis in the organism.

Carotenoids↗
PubMed1976

Abolition of ischemic response to atrial pacing following aortocoronary bypass surgery.

To determine the effect of successful aortocoronary bypass surgery (ACBS) on left ventricular (LV) function, the ischemic response to right atrial pacing (RAP) was studied in 22 angina patients before and 3.8 +/- 1.1 months after surgery. All patients were free of angina after ACBS and had at least one patent graft. Before ACBS, RAP induced angina in 15 patients (Group 1) but not in 7 patients (Group 2). After ACBS, no patient had angina with RAP despite the increased maximum rate of pacing. Post-pacing LV end-diastolic pressure (LVEDP) after ACBS decreased in Group 1 from 25 +/- 6 to 15 +/- 6 mm Hg (P less than 0.01), but not in Group 2. Changes in ejection fraction, cardiac output, resting LVEDP, or LVEDP after LV angiography were not significant in either group and were therefore not useful in evaluating the result of ACBS. However the ischemic response to right atrial pacing was abolished by successful aortocoronary bypass surgery, suggesting improved myocardial perfusion during stress.

Angina Pectoris↗
PubMed1975

Gas-liquid chromatography of carotenoids and other terpenoids.

The retention behaviour of over seventy terpenoids on three silicone polymer liquid phases under both isothermal and temperature-programmed conditions is reported. Terpenoids with conjugated unsaturation (e.g., carotenoids) were hydrogenated prior to analysis in order to prevent thermal decomposition. Analyses of the acetates and TMS ethers of both the natural hydroxycarotenoids and their perhydroderivatives are also reported. In addition, a system is described for the routine analysis of terpenols, including those whose pyrophosphates are intermediates in sterol and carotenoid biosynthesis.

Acetylation↗
PubMed1974

Triterpenoid carotenoids and related lipids. The triterpenoid carotenes of Streptococcus faecium UNH 564P.

1. The occurrence of a novel series of triterpenoid carotenes in Streptococcus faecium UNH 564P is reported. 2. This series, which comprises the C(30) analogues of phytoene, phytofluene, zeta-carotene, 7,8,11,12-tetrahydrolycopene and neurosporene, appears to be analogous to the C(40) Porter-Lincoln series and a pathway of triterpenoid carotene dehydrogenation is proposed to account for the formation of these compounds. 3. Two cis isomers of the C(30) analogue of neurosporene are described. 4. An appropriate system of nomenclature for these novel compounds is proposed.

Carotenoids↗
PubMed1974

Triterpenoid carotenoids and related lipids. Triterpenoid monohydroxy- and monoglucosyloxy-carotenoids from Streptococcus faecium UNH 564P.

1. The characterization of two novel triterpenoid xanthophylls occurring in Streptococcus faecium UNH 564P is described. 2. Both are derived formally, and probably biosynthetically, from the C(30) analogue of neurosporene and have been identified as 4-hydroxy-4,4'-diaponeurosporene and its glucoside, 4-d-glucopyranosyloxy-4,4'-diaponeurosporene. 3. Problems associated with the use of specific glucosidases in defining the anomerism of carotenoid glucosides are discussed.

Acetylation↗