Biomedical subjects
S Seely
Publications and source records attributed to S Seely.
Is calcium excess in western diet a major cause of arterial disease?
The daily requirement of a young adult for calcium is 300-400 mg, the quantity consumed in many third-world countries. The dietary intake can be doubled or trebled by consumption of milk, thus half a litre of milk, consumed by many individuals daily in prosperous countries, adds 600 mg. The need for calcium is greatly reduced in old age, so that the excess from a given intake becomes more pronounced. The potential hazard of a high intake is that a small fraction finds its way into soft tissues. The aorta is notably prone to calcification, resulting in loss of elasticity. The aorta and its large branches constitute an elastic reservoir, distended during systole and contracting in diastole. This contraction provides the energy for the maintenance of diastolic pressure, which decreases with the deterioration of elasticity and needs a continually increasing systolic pressure to restore its normal value. The heart is disadvantaged in two ways. Its work is increased by having to eject the systolic volume into a stiffer reservoir, and the diastolic filling of the coronary arteries is reduced. This is the main cause of hypertension in old age--there is no increase in blood pressure with age in undeveloped countries where intake of calcium is low. The best cure would be prevention: the reduction of intake of calcium in prosperous countries. Failing that, phytic acid is suggested as the best calcium antagonist. Phytic acid, a natural product present in grains, converts dietary calcium into insoluble phosphates which pass unabsorbed through the digestive tract. The presently used calcium antagonists are not so satisfactory.
The gender gap: why do women live longer than men?
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Cardiac muscle: a miracle of creation.
The paper proposes that energy conversion in muscle is a two-step process, chemical energy being first converted into electrical energy which is then converted into mechanical work. The chemo-electrical transducers are, in effect, minute voltaic cells--more precisely calcium-magnesium cells--with the magnesium electrodes on myosin heads and the calcium electrodes on the C subunits of troponin molecules associated with actin filaments. These cells are established when, after the passage of an action potential, calcium ions are admitted to the sarcomere. In an energy-consuming process, calcium ions are bound to troponin molecules, the energy for the process being supplied by hydrolysis of adenosine triphosphate. The electro-mechanical transducer utilises the electrostatic field established between the oppositely charged electrodes of the voltaic cell. As the two are pulled towards each other, doing mechanical work, energy is supplied by the voltaic cells. In the course of this action, calcium ions go back into solution. The action ceases when, after the passage of an action potential, calcium ions are withdrawn into the sarcoplasmic reticulum.
Atherosclerosis or hardening of the arteries?
This paper discusses the consequences of the loss of elasticity by the aorta and large arteries in old age. As the heart compresses its own arteries during contraction, much of the myocardium is perfused only during diastole, so that adequate diastolic pressure is a vital necessity for it. Diastolic pressure depends largely on the elasticity of the aorta and large arteries, constituting the arterial reservoir, which stores energy by its distension during systole and returns it to the system during diastole. Loss of elasticity with advancing age means that the arterial reservoir can store less energy and becomes less effective in evening out the pulsating pressure imposed on the system by the left ventricle. Hence, systolic pressure tends to rise and diastolic pressure to drop. Together with other imperfections developing in old age, and combined with atherosclerotic and thrombotic obstructions, circumstances can arise when the arterial reservoir becomes incapable of producing sufficient pressure for the adequate perfusion of some regions of the heart.
Similarities and differences between the epidemiology and possible dietary causes of coronary arterial disease and strokes.
The findings of a previous statistical study of the relationship between food consumption and mortality from coronary arterial disease are compared with those of a new study of food consumption and cerebrovascular disease. The previous study found strong positive correlation between male mortality from coronary arterial disease and the consumption of two food items, milk and oats. Stroke mortality appears to be linked with the consumption of a wide variety of proteinaceous plants. These can be divided into two groups, one with an apparently strong and the other with an apparently mild effect. The strong group consists of the protein content of pulses, oats, maize and rye, the milder group of the protein content of wheat, rice, barley, potatoes and vegetables. The relative effect of the two groups of proteins is of the order of 6/1, but the proteins with a relatively mild effect are consumed in large quantities in comparison with those having a strong effect so that their effect is not negligible. The correlation coefficient between male cerebrovascular mortality in the younger age groups and the combined consumption of the two groups of plant proteins is 0.91. That between male mortality from coronary arterial disease and the consumption of milk and oats found in the previous study was 0.94.
Diet and coronary arterial disease: a statistical study.
Statistical analysis comparing mortality rates from coronary arterial disease with food consumption in 21 countries belonging to the Organisation of Economic Cooperation and Development is presented. In a preliminary process correlation coefficients are calculated for coronary mortality and all food items appearing in statistics collected for food consumption as well as for some combinations of food items. The highest correlations obtain with oats, milk proteins (other than the protein content of cheese), milk fats and sugar. These items are investigated in greater detail with respect to mortality from coronary arterial disease in males and females in various age groups and for various time intervals between the dates of mortality and statistics for food consumption. Correlations tend to increase in the older age groups and with longer time intervals. The highest correlation coefficient found is 0.94 for deaths due to coronary arterial disease for males in the 65-74 age group with the combined consumption of oats and milk proteins.
Errors in mortality statistics.
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An electrodynamic (moving field) theory of muscular contraction.
It is proposed that muscular contraction is the result of electrostatic attraction between oppositely charged areas on actin and myosin filaments. On the latter charged areas are assumed to be moving, always a step ahead of stationary charged areas on actin filaments, the moving charges pulling the stationary charges, hence the actin filaments, with them. It may be noted that electric motors in human technology work on a similar moving field principle. On myosin filaments minute charged areas are assumed to spiral along the surface of the filament on 2 or 3-start helical paths, probably the latter, thus engaging with adjacent actin filaments in a screw-like fashion. The spiralling charges follow each other like peristaltic waves, engaging with an increasing number of static fields on actin filaments as interdigitation proceeds. The source of the electrostatic charges are assumed to be minute voltaic cells, one associated with every myosin head. It is suggested that they could be calcium-magnesium cells, calcium adsorbed by troponin complexes on actin filaments constituting one electrode, and magnesium complexed with ATP on myosin filaments the other. The potential difference that has to exist between actin and myosin filaments, if muscles are to be capable of developing a maximum force of 20 N per cm2, is calculated at about 50 mV.
Relation between pork consumption and cirrhosis.
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Mineral deficiency and atherosclerosis.
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Diet and atherogenesis.
Diet is probably correlated with the prevalence of atherosclerosis in the more prosperous countries of the world. Attempts to discover the responsible items of diet would be facilitated if systematic, statistical comparisons were made between the diets in some high and low risk areas. A particular area which might lend itself for this survey is the block of five countries consisting of Austria, Czechoslovakia, Hungary, Poland and Romania. The first three of these constitute a high risk area, with mortality from ischemic heart disease of the order of 250 per year per 100,000 population, the last two a low risk area with mortality of the order of 75. Many relevant conditions, like standard of living, expectation of life, climate, etc. are reasonably similar in the five countries. Items of diet, the consumption of which is consistently higher in the high risk than in the low risk countries could constitute a short list of suspected atherogens.
Basic principles of cellular organization.
The hypothesis is put forward that the division of the animal body into three germ layers represents not only histological, but also functional specialization, the ectoderm taking over functions through which the animal is in contact with, acted upon or reacts to the external world, the entoderm metabolism and the mesoderm architectural and mechanical organization. This is assumed to mean that the tasks of life have been divided into three large function domains at an early stage of multicellular evolution, each germ layer taking over one domain and developing largely independently of the other two in the further course of phylogeny. The germ layers are autonomous in their own spheres, giving the body, in effect, a tripartite government. The potentiality of conceptual thought is inherent in all germ layers, reaching a high state of development in the entoderm and mesoderm at a much earlier stage of development than in the ectoderm. The animal body, as a whole, is in control of all its biologic activities; it is a self-designing, self-developing and self-perpetuating entity. The control of cellular organization is a mesodermal task.
The mortality or immortality of cell lines.
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The therapeutic effect of hemodialysis on schizophrenia: comments and further possibilities.
Intermittent hemodialysis was recently found to have a therapeutic effect on schizophrenia, pointing to biochemical disturbances and possibly to renal malfunction as the cause of some forms of mental disorder. This paper points out that intermittent hemodialysis is not equally effective for the elimination of all solutes in the plasma. It can dispose of significant quantities of substances for which the normal urine/plasma concentration ratio is small, not of substances which the kidney concentrates in the urine by a large factor. It is further pointed out that for substances with a small urine/plasma concentration ratio thermogenic sweating could also constitute an effective means of disposal and its use is suggested as possible alternative to hemodialysis.
Diet and atherogenesis.
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Blood donors and coronary disease.
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