PubMed Health⌕ Search

Biomedical subjects

A Steer

Publications and source records attributed to A Steer.

At least 19 recordsLinked to original sources

Cryosolvents useful for protein and enzyme studies below -100 degrees C.

For the study of protein structure, dynamics, and function, at very low temperatures it is desirable to use cryosolvents that resist phase separation and crystallisation. We have examined these properties in a variety of cryosolvents. Using visual and X-ray diffraction criteria, methanol:ethanediol (70%:10%), methanol:glycerol (70%:10%), acetone:methoxy-ethanol:ethanediol (35%:35%:10%), dimethylformamide:ethanediol (70%:10%), dimethylformamide (80%), methoxyethanol (80%), and methoxyethanol:ethanediol (70%:10%) were all found to be free of phase-changes down to at least -160 degrees C. The least viscous of these, methanol:ethanediol (70%:10%), was miscible down to -125 degrees C and showed no exo or endothermic transitions when examined using DSC. It is therefore potentially particularly suitable for very low temperature cryoenzymology.

Cryoprotective Agents↗

Autopsy study of small cardiac scars in Japanese men who lived in Hiroshima, Japan and Honolulu, Hawaii.

Japanese men long resident in Honolulu, Hawaii have significantly more ischemic heart disease but significantly fewer small cardiac scars than men in Hiroshima, Japan. These scars occur in three forms:(1)small scars in the mural myocardium which account for the difference in frequency of small lesions in the two cities and are of uncertain etiology; (2)areas of diffuse fibrosis in the papillary muscles. These are equally frequent in the two cities and are associated with advancing age and sclerosis of papillary muscle arteries; and(3)focal scars in the papillary muscles. These are more frequent in Honolulu than Hiroshima. They are healed infarcts due to ischemic heart disease and are associated with a severe degree of extramural coronary artery atherosclerosis. Small mural myocardial scars, when present, are usually found in multiple sites. Their increased frequency in Hiroshima is not explained by differences in age or heart weight. They are more common in the presence of sclerosis of intramural small arteries, but this association also fails to explain the intercity difference. It is supected that the excess of these small cardiac scars in Hiroshima males reflects past privation. There is no evidence that is is related to A-bomb radiation exposure.

Aging↗

Small cardiac lesions. Fibrosis of papillary muscles and focal cardiac myocytolysis.

Three types of small cardiac lesions were described and illustrated: (1) focal type of papillary muscle fibrosis, evidently a healed infarct of the papillary muscle present in 13% of autopsies, is a histologically characteristic lesion associated with coronary artery disease and healed myocardial infarction, (2) diffuse type of papillary muscle fibrosis, probably an aging change present in almost half of the autopsies, is associated with sclerosis of the arteries in the papillary muscle, is identifiable histologically, and apparently is not associated with any cardiac abnormality, and (3) focal cardiac myocytolysis, a unique histologic lesion, usually multifocal without predilection for any area of the heart, is associated with ischemic heard disease, death due to cancer complicated by nonbacterial thrombotic endocarditis and microthrombi in small cardiac arteries as well as with other diseases. Differentiation of the 2 types of papillary muscle fibrosis is important in the study of papillary muscle and mitral valve dysfunction. Focal cardiac myocytolysis may contribute to the fatal extension of myocardial infarcts.

Aged↗

Accuracy of diagnosis of cancer among autopsy cases: JNIH--ABCC population for Hiroshima and Nagasaki.

The accuracy of death certificate diagnoses of cancer in the fixed population of about 100,000 samples in Hiroshima and Nagasaki was determined for the period 1961 approximately 1970 by comparison with autopsy findings. In general, when the death certificate listed cancer as a cause of death it was found at autopsy in a high proportion of cases. However, cancer was not always reported on death certificates, indicating that cancer occurs more frequently than recorded by official mortality statistics. Older persons, persons who die at home, and persons with certain cancers are more likely not to have cancer named on their death certificates. It is estimated that in the 10,749 deaths occurring at home or in hospital, there were 32% more deaths due to cancer than certified on death certificates (3,095 vs. 2,345) and for persons aged 70 or more dying at home it is estimated there were 55% more stomach cancer (269 estimated vs. 174 listed) and 244% more lung cancer (141 estimated vs. 41 listed) than were certified on death certificates. The death certificate is not a good source of information for cancer of the cervix because many cases of this disease reported on death certificates as cancer of the uterus. This practice needs to be taken into account in the use of mortality data for cervical cancer in Japan.

Age Factors↗

A comparative pathology study of myocardial lesions and atherosclerosis in Japanese men living in Hiroshima, Japan and Honolulu, Hawaii.

Autopsies were conducted on Japanese men from 45 to 71 years of age in Hiroshima, Japan (191 patients) and in Honolulu, Hawaii (298 patients). They were performed according to a common protocol. In both locations the patients studied were representative of decedents from population-based cohorts with respect to age and cause of death. The degree of atherosclerosis in the coronary arteries and aorta, assessed according to the panel method, was found to be substantially more severe in men in Hawaii than in those in Japan. Areas of recent myocardial necrosis were 3.5 times more frequent in men in Honolulu than in those in Hiroshima. Large myocardial scars were 1.5 times more frequent in the men in Honolulu. It was characteristic of men in Honolulu that severe atherosclerosis and myocardial lesions appeared at younger ages than in those in Hiroshima. These data demonstrate that there is an increase in the frequency and severity of ischemic lesion in the myocardium of Japanese who have migrated to Hawaii and that this increase is the result of atherosclerosis of the extramural segments of the coronary arteries.

Aged↗

Lung cancer at autopsy in A-bomd survivors and controls, Hiroshima and Nagasaki, 1961-1970. II. Smoking, occupation, and A-bomb exposure.

The apparent effect of ionizing radiation on lung cancer in A-bomb survivors has not been large enough to still doubts as to its validity. It has seemed essential to determine whether the apparent radiation effect could have resulted from a confounding of heavy smoking and high radiation dose, or if the occupational exposure of high-dose subjects with lung cancer was suggestive of the influence of environmental hazards other than radiation. The available series consists of 204 subjects with lung cancer verified by autopsy, 61 of whom were low-dose (less than 1 rad) and 13 high-dose (200 + rads) subjects. No evidence could be found that the influence of either smoking or occupational exposure upon lung cancer was exerted so as to suggest that the apparent radiation effect is other than real. The study also provides additional evidence of the relationship between lung cancer and smoking in Japanese.

Aged↗

Other tumors.

Explore the source record for details and available documents.

Bile Duct Neoplasms↗