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Biomedical subjects

R C Noble

Publications and source records attributed to R C Noble.

At least 181 records · Page 10Linked to original sources
PubMed1971

Production of double zones of hemolysis by certain strains of hemolytic streptococci of groups A, B, C, and G on heart infusion agar.

This report describes the appearance of a double zone of hemolysis around surface colonies of certain strains of streptococci of groups A, B, C, and G incubated aerobically on sheep blood-Heart Infusion Agar. The occurrence of the altered hemolytic pattern was related to peroxide production by the organism. Anaerobic conditions and the incorporation of catalase into the agar abolished the double-zone pattern and caused reversion of the organisms to a beta-hemolytic pattern. The double-zone pattern can be confused with alpha hemolysis on surface growth.

Aerobiosis↗
PubMed1970

Acid-precipitated M protein compared with a column-eluted M protein preparation from type 12, group A Streptococci.

An M protein preparation of group A streptococci, precipitated with 0.03 m sodium acetate buffer (pH 4.0) was compared with a column-eluted M protein preparation. Absorption spectra and methyl pentose content were similar in both preparations. Acrylamide gel electrophoresis patterns were different. Gel diffusion demonstrated two lines of fusion in the preparations. More antigens could be demonstrated in both preparations by using immunoelectrophoresis. Neither the pH 4 precipitate nor the column-eluted preparation appeared to be a pure M protein preparation.

Antigens↗
PubMed1968

Adipose tissue and heat production in the new-born ox (Bos taurus).

1. A histological examination of adipose tissue from 1- and 6-day-old calves showed a structure typical of white adipose tissue and no evidence of brown adipose tissue.2. Infusion of noradrenaline (1.0 mug/kg.min I.V.) into 1-to 6-day-old calves affected heart rate and respiratory rate but did not increase heat production, rectal temperature, skin temperature or skin evaporative loss.3. Cold exposure led to shivering and an increased oxygen consumption in the 6-day-old calf.4. Blood samples taken from 6-day-old calves in the cold (-1 degrees C) appeared to have a higher proportion of unesterified fatty acids in the total blood lipid than samples taken in an environment of 20 degrees C, but no change in fatty acid composition was found.5. It has been concluded that there is no non-shivering thermogenesis in the young calf.

Adipose Tissue↗
PubMed1966

An investigation of serum lipoproteins and of their contribution to mild fat in the dairy cow.

1. Tritium-labelled olive-oil triglycerides were introduced into the rumens of lactating cows and the specific activities of the lipids of milk and plasma and of serum lipoproteins were measured. 2. On treatment of serum with dextran sulphate it was found that the lipid of the precipitated beta-lipoproteins consistently had a specific activity-time curve with a maximum comparable in value with, and occurring earlier than, that of the milk fat. 3. On fractionation of the lipids of these lipoproteins it was found that only the triglycerides and diglycerides had specific activity-time curves with maxima greater than that of milk fat, and on radioactivity data alone they are the only blood constituents studied that meet the requirements for being the precursor of milk fat. 4. From a consideration of abundances and the mean specific activities over the period of the experiment it is shown that the contribution of the diglycerides to the radioactivity in the milk fat must have been negligible and that only the triglycerides could have been responsible for all the radioactivity found in it. 5. Although no other fraction could alone have been responsible for all the radioactivity in the milk fat, at least one, the phospholipids, could have made some contribution. 6. It is calculated that 35-48% by weight of milk fat was derived from the beta-lipoprotein triglycerides, according to whether the phospholipids made an improbably large contribution or none at all.

Animals↗