Search PubMed⌕ Search

Biomedical subjects

R C Noble

Publications and source records attributed to R C Noble.

At least 109 records · Page 6Linked to original sources
PubMed1982

Fatty acid biosynthesis in sheep placenta and maternal and fetal adipose tissue.

The rates of fatty acid synthesis from 3H2O and [1-14C]-acetate as substrates have been determined in sheep placental tissue and maternal and fetal adipose tissues in vitro. The tissue was obtained from sheep approximately 28 or 3 days from parturition. Placental tissue synthesised fatty acids at an appreciable rate and newly synthesised fatty acids were apparently transferred from the tissue to the incubation medium. When the results were expressed per unit of tissue weight, fetal adipose tissue synthesised fatty acids much more rapidly than did placental tissue but because there was much more of the latter tissue, the total amounts of fatty acids synthesised by each were comparable. However, it appeared that most of the fatty acids (approximately 80%) in the fetus must have been derived from the maternal plasma. The nature of the fatty acids synthesised de novo was investigated, as was the manner of their esterification.

Acetates↗
PubMed1981

The metabolism of 18:0 and 18:2(n-6) by the ovine placenta at 120 and 150 days of gestation.

The effects of approach of parturition in the sheep on the incorporation of 18:0 and 18:2(n-6) into the placenta lipids and on the activities of the delta 9- and delta 6-desaturase enzymes of placental tissue have been studied in vitro. The incorporation of 18:0 into the esterified lipids of placental tissue between the 120th and 150th days of gestation declined markedly; the high level of incorporation of 18:2(n-6) into the esterified lipids of the placenta (some 2-fold higher than 18:0) remained constant over the gestational period. While placental delta 9-desaturase activity was the same at 150 days as at 120 days of gestation, the activity of the delta 6-desaturase enzyme increased significantly. These results are discussed in relation to the fetal demand for fatty acids near term and the differences that exist between the mechanisms of maternal-fetal transfer of 18:0 and 18:2(n-6) in the sheep.

Animals↗
PubMed1981

Detection of estrus with cows administered testosterone via injections and/or silastic implants.

Over a three year period 8 cows and 2 heifers were administered testosterone via injections and/or silastic implants. During and subsequent to treatments, blood samples were collected for determination of testosterone and cows were observed for male sex behavior. Male sex behavior was induced by administering 200 mg of testosterone propionate every other day for 20 days, and once induced, male sex behavior was maintained by injections of 200 mg of testosterone propionate every 10 days or by two 15 cm silastic implants containing testosterone propionate. Male sex behavior was also induced and maintained by administering an injection of testosterone enanthate (1 gm) and testosterone propionate (200 mg) and two 15 cm silastic implants containing testosterone propionate at the same time. Cows which are administered testosterone in this manner detected 94% of 231 females that were in estrus 342 times.

Journal Article↗
PubMed1981

Trimethoprim-sulfamethoxazole therapy for infective endocarditis.

A man with stenosis of the aortic valve acquired endocarditis after abdominal surgery. Klebsiella pneumoniae and Acinetobacter calcoaceticus were cultured from his blood. The blood cultures remained positive despite intravenous gentamicin and cephalothin to which the organisms were sensitive in vitro. Ultimately, the blood was sterilized by a combination of gentamicin and trimethoprim-sulfamethoxazole taken orally. The course of the patient was complicated by cardiac arrest and pericardial tamponade caused by a valve ring abscess and a dissecting mycotic aneurysm of the coronary sinus of Valsalva. Aortic valve replacement and right coronary artery bypass were performed. A prolonged course of trimethoprim-sulfamethoxazole was given postoperatively, and the patient has had no evidence of recurrent infection after five years. Trimethoprim-sulfamethoxazole, in combination with other antibiotics, has been successfully used to treat other patients with bacterial endocarditis and thus may be an alternative for patients in whom conventional therapy has failed.

Acinetobacter Infections↗
PubMed1981

The maternal diet and its effect on the lipid composition and osmotic fragility of neonatal ovine erythrocytes.

Two groups of pregnant ewes were fed either a control diet or one in which part of the concentrate ration was replaced during the last 8 weeks of gestation with a protected polyunsaturated fatty acid (PUFA) supplement. The feeding of the PUFA diet resulted in significantly higher proportions of linoleic acid in the plasma lipids of the ewes and both linoleic and arachidonic acids in the plasma lipids of the lambs. The erythrocytes were composed almost totally of free cholesterol and phospholipids and, although no significant difference was observed in the overall phospholipid compositions of the erythrocytes from the two groups of lambs, there were differences from those of the adult. Fatty acid analysis of the erythrocyte phospholipids showed marked difference between ewes and lambs and also between the two groups of lambs. In particular, the proportions of linoleic and arachidonic acids were higher in the erythrocyte phospholipids from PUFA lambs compared with those from control lambs. This compositional change correlated with a greater resistance to haemolysis and it is suggested that this might be indicative of beneficial effects on the membrane stability of other cells.

Animals↗
PubMed1981

Novel determination of protein, fat, and lactose of milk by liquid scintillation counter.

A method for routine determination of protein, fat, and lactose contents of milk is based on the ability of a scintillation counter to measure coloration or opalescence through attenuation of photons emitted from sealed miniature carbon-14 and hydrogen-3 radioactive standards. A series of simplified and accurate analytical procedures enable full advantage to be taken of the automatic facilities on the modern liquid scintillation counter. The methods provide several advantages over existing procedures. Accuracy of quantification was high as assessed by comparing the results with those derived by recommended Kjeldahl, Gerber, and colorimetric procedures for protein, fat, and lactose determinations, respectively.

Animals↗
PubMed1980

A single-step method for determination of the specific radioactivity of lipids.

The use of a liquid scintillation counter to measure both the mass and the radioactivity content of charred 14C-labeled lipid bands from thin layer chromatoplates has been evaluated. Following lipid mass determination from a measurement of the external standard channels ratio, a suitable choice of counting parameters enabled a reproducible and efficient 14C count to be obtained over virtually the whole range of lipid concentrations tested. Although the charring procedure resulted in some loss of radioactivity, the efficiency of counting remained high enough for accurate dpm measurements.

Carbon Radioisotopes↗
PubMed1980

Auxotypes and antimicrobial susceptibilities of Neisseria gonorrhoeae in black and white patients.

Isolates of Neisseria gonorrhoeae from 100 white and 113 black patients attending a venereal disease clinic were examined for their susceptibility to ampicillin, penicillin, tetracycline, and spectinomycin. The isolates were also characterised by gonococcal auxotyping. Gonococcal isolates from black patients were more resistant to the antibiotics than those from white patients, since the former were infected with the more antibiotic-resistant auxotypes (Pro, Zero, and Arg) whereas the latter were infected with the more antibiotic-susceptible auxotypes (AHU and others). These data indicate a preferential infection by sub-populations of Neisseria gonorrhoeae in two racial groups.

Anti-Bacterial Agents↗
PubMed1980

Relationship of the interval between infections and the similarity of gonococcal strains in recurrent gonorrhoea.

Paired gonococcal isolates from 38 patients with recurrent episodes of gonorrhoea at varying intervals were examined for similarity by means of gonococcal auxotyping and susceptibility to antibiotics. A different gonococcal strain was the cause of the second infection in 53% of the patients. Longer intervals between infections were significantly associated with greater numbers of dissimilar strains as a cause of the second infection. The same strain was usually found in infections occurring within 60 days of each other whereas different strains were more likely to cause infections occurring more than 60 days apart. The isolates causing the second infection were significantly more susceptible to penicillin.

Anti-Bacterial Agents↗
PubMed1980

Gonorrhea in Rotterdam caused by penicillinase-producing gonococci.

Recently the prevalence of strains of penicillinase-producing Neisseria gonorrhoeae (PPNG) in the Netherlands has increased. A study of demographic and clinical data from patients with gonorrhoea due to PPNG strains, and of the biological characteristics of the strains isolated in Rotterdam, show that Asian strains of PPNG seem at present to be endemic in the Netherlands. Spectinomycin was found to be effective in the treatment of patients with gonorrhoeea due to PPNG strains.

Female↗