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Biomedical subjects

L Black

Publications and source records attributed to L Black.

At least 73 records · Page 4Linked to original sources
PubMed1978

Calcification in an intramyocardial mass lesion: isolated calcification of an accessory papillary muscle in a patient with mitral prolapse.

Cardiac catheterization in a 50-year-old male with mitral leaflet prolapsed revealed a filling defect with calcification in the high posterolateral wall. At surgery, the lesion was found to be a calcified accessory papillary muscle with thickened, calcified chordae to the posterior leaflet. The calcification and fibrosis were felt to be due to friction lesions between elongated chordae and the endocardium. Intracardiac calcification in mitral leaflet prolapsed may suggest calcified mitral apparatus.

Calcinosis↗
PubMed1978

Intraoperative autotransfusion in elective and emergency vascular surgery.

Intraoperative autotransfusion was studied in 62 patients undergoing elective or emergency thoracic or abdominal vascular surgery systemic heparinization. The results in 58 patients who received a mean autotransfusion volume of 1.8 liters were compared with a group of four patients in whom 9 liters of blood was autotransfused. The quality of the autotransfused blood also was studied and was shown to have a normal platelet count (mean, 144,000/cu mm) and normal fibrinogen value (mean, 212 mg%). No significant differences in the hematological or coagulation parameters measured were detected in the groups given moderate or massive autotransfusion. The mean homologous blood requirement during the hospital admission in the "moderate" group was 300 ml and in the "massive" group 1,000 ml. With careful technique excessive hemolysis or pulmonary microaggregate embolism does not occur; 75% of patients required no homologous blood throughout their hospital admission. No complications which would be attributed to autotransfusion were seen in either group. It is concluded that intraoperative autotransfusion is safe and effective and deserves wider application.

Abdomen↗
PubMed1977

Allergy in cattle after foot-and-mouth disease vaccination.

BHK cell derivatives, saponin and aluminium hydroxide, all of which are commonly present in foot-and-mouth disease vaccines, were injected subcutaneously into 10 cattle and the serum levels of anti-BHK reagins and passive haemagglutinating antibodies were followed. The reaginic antibodies rose to a peak titre one to two weeks after the stimuli and waned during the third week. They had a serum half life of about three days, assuming exponential decay, and were generally undetectable four weeks after last contact with antigen. Passive haemagglutinins were slower to develop and two or more stimuli were usually required to produce detectable antibody levels. They were also slower to subside and were demonstrable for at least 10 weeks after last contact with antigen in most cases. Clinical reactions provoked by the intradermal injection of lysate into sensitised cattle were not correlated with the serum reagin or passive haemagglutinin levels or their ratio to one another at time of the reactions. The reasons for this are discussed.

Adjuvants, Immunologic↗
PubMed1977

The adjuvant activity of saponin and aluminium hydroxide for promoting reagins.

Saponin and aluminium hydroxide were compared as adjuvants for promoting serum reagins in cattle using BHK cell lysate as allergen and the passive cutaneous anaphylaxis test to demonstrate the antibodies. Saponin was the better adjuvant and provoked reagins in all the injected cattle while aluminium hydroxide did so in only 2 or 5 animals. The titres were also higher in the former case. A combination of both adjuvants stimulated reagin titres marginally higher than saponin alone while BHK cell lysate without adjuvant failed to provoke demonstrable reagins.

Adjuvants, Immunologic↗
PubMed1976

Turbidimetric and diffusion assay of bacitracin in feeds.

A manual turbidimetric method for determining zinc or methylene disalicylate bacitracin in feeds was developed. When zinc ions (10-4M) were added to the medium and the phosphate ion concentration in standard solutions was decreased to 1%, the median response of Streptococcus faecalis was about 0.038 unit. Feeds analyzed by the turbidimetric assay should be prewashed with petroleum ether and extracted with pyridine as in 42.204. Zinc bacitracin standards added to swine and broiler rations were recovered at 93.1-102.6% by the turbidimetric method. Excellent agreement between the manual turbidimetric method and the plate assay was also obtained for finished feeds containing the zinc or methylene disalicylate salt of the antibiotic. The turbidimetric method appears to have high accuracy and precision. It is more rapid and less costly than the plate assay.

Animal Feed↗
PubMed1975

The evaluation of hypersensitivity tests in cattle after foot-and-mouth disease vaccination.

The response to passive cutaneous anaphylaxis, dermal hypersensitivity and intravenous provocation tests has been compared in 30, 40, 31 and 24 cattle injected with foot-and-mouth disease vaccine 0, 1, 2 and 3 times respectively, using vaccine components and other substances as test materials. Reaginic antibodies demonstrated by passive cutaneous anaphylaxis in goats, were directed against BHK 21 cell extracts (20), hydroxypropylmethylcellulose (3) and an unidentified vaccine component (3), and distributed in 0, 5, 19 and 75 per cent of the cattle vaccinated 0, 1, 2 and 3 times. None of the animals showed clinical signs of allergy after vaccination. When BHK 21 cell extract was injected intradermally a significant correlation was noted between the development of large weals and the presence of reagins although the size of the weals was not correlated with the reagin titres. In the case of hydroxypropylmethylcellulose a similar trend was evident. The majority of cattle with large dermal weals possessed reagins but the number of reactions was too small for statistical evaluation. Dermal reactions to sodium penicillin, sodium carboxymethylcellulose, saponin and whole vaccine occurred in both unvaccinated and vaccinated cattle but BHK 21 cell lysate and normal bovine serum provoked weals which increased in frequency according to the number of vaccinations experienced. Intravenous hydroxypropylmethylcellulose elicited a response in all the animals previously injected with certain batches of vaccine but cell extract intravenously produced a clinical response in half the tested animals which was uncorrelated with the results of the passive cutaneous anaphylaxis or dermal hypersensitivity tests.

1-Propanol↗
PubMed1975

Hypersensitivity in cattle after foot-and-mouth disease vaccination: response to hydroxpropylmethylcellulose.

Intravenous provocation (IVP) tests demonstrated that hydroxypropylmethylcellulose (MC) was able to elicit anaphylactic signs in cattle vaccinated with foot-and-mouth disease (FMD) vaccine produced at one centre but not with similar vaccine produced at another. The former vaccine also provoked serum reagins which were demonstrated by passive cutaneous anaphylaxis (PCA) tests in goats. Reaginic sera which reacted specifically with MC were used in PCA tests to screen samples taken serially from the vaccine production lines. The reactions observed suggested that a substance with MC or similar specificity was present in the antifoaming agent routinely added to vaccines.

Amino Acids↗
PubMed1969

Morbidity, mortality and medical care in the Keewatin area of the Central Arctic--1967.

The available medical facilities in the Keewatin area of Canada's Central Arctic have been described, along with the problems relating to provision of medical care. Causes of death and population statistics for 1967 have been detailed. The more frequent disease conditions have been discussed.Recommendations for improvements in medical care have been made; these include research into various conditions, an increased number of specialist visits and the inclusion of Churchill Hospital in a residency training program. Other recommendations relate to community planning, community sanitation and employment opportunities.

Arctic Regions↗