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PubMed1987

The changing role and legitimate boundaries of epidemiology: community-based prevention programmes.

Epidemiology is the basic science of public health. It combines medical and social sciences, both of which are developing with new inventions. Therefore, the role of epidemiology and its boundaries are also changing over time. An important role of epidemiology is to develop and implement community-based control programmes for major diseases in the community. Such programmes are essential for large scale public health policy. It is necessary that epidemiological research can as freely as possible test new methods of disease prevention and health promotion. The first community-based control programme for cardiovascular diseases, the North Karelia Project is reviewed against this background. At present, it is still possible to define the boundaries of epidemiology geographically and culturally, but in the future, however, it will become more difficult. There is no doubt that epidemiology will remain as the basic science of public health but the scope of public health problems are growing much wider. These include the prevention of the final epidemic--the destruction of our planet by nuclear bombs. In the control of the existing epidemics and in the prevention of new ones the boundaries of epidemiology cannot stay rigid but they must be changing as new facts about the emerging public health problems are identified.

Cardiovascular Diseases↗
PubMed1987

Hot and cold in women's ethnotherapeutics: the American-Mexican West.

The purpose of this paper is to report the current status of hot/cold principles in the ethnotherapeutics of women of southwestern U.S.A., northwestern Mexico. The paper presents a secondary data analysis from three studies, including a data bank of Women's Ethnotherapeutic Agents derived from literature searches, interviews of women in research of Mexican American Grandmothers as Health Care Advisors, and research in the historical roots of the ethnotherapeutic agents used in contemporary domestic medicine. This report presents women's home remedies, what these remedies are believed to do, and the sources of this domestic therapy knowledge. It concentrates on persistence and change in one aspect of the theoretical base of these remedies, their humoral complexional classification. In the analysis of data from these studies, continuation of aspects of the hot/cold theory is demonstrated. It is suggested that the persistence is tacit, with the lack of articulated knowledge of humoral theory today stemming from the content of contemporary remedy books. Instead of arguing either diffusion or independent invention, commonly held ethnophysiological concepts are offered as a possible explanation for the persistence of hot and cold therapy practices.

Cold Temperature↗
PubMed1993

Social research in health and the American sociopolitical context: the changing fortunes of medical sociology.

The fortunes of medical sociology, like other public policy-relevant disciplines, are shaped by political dynamics and prevailing values and attitudes. In the 1980s the field, which views disease and disability as consequences to a substantial degree of material conditions, social stratification, and inequalities among varying strata, lost ground to economics as societal attention focused on cost containment issues. Sociological concern with social structures clashed with dominant conservative and individualistic perspectives and the increased focus on personal responsibility and market strategies. There was decreasing tolerance in policy circles for the view that health, and the problems affecting disenfranchised groups such as the poor, the homeless, the uninsured and people with disabilities, were more due to our politics and social arrangements than the personal characteristics of those affected. Thus, little attention has been given in public health discourse to how life imperatives and social opportunities and constraints shape behavior. The paper documents the important role of the social sciences in health services research with special attention to examining the social context of the RAND Health Insurance Experiment. Although many of the questions medical sociology address sit on the periphery of policy-makers' concerns, a strong case is made for the revitalization of a critical scholarly role in medical sociology. I conclude, given the short and longterm problems we face in medicine and health, that we would have to invent a vigorous critical medical sociological enterprise if we did not already have one.

Forecasting↗
PubMed1993

Strategies of influence in medical authorship.

The notion of a rhetoric of science argues that scientific writing is not unproblematically neutral and objective, but rather laden with both theory and value and necessarily persuasive. The nature of persuasion within the profession of medicine is studied here through an analysis of rhetorical strategies at work in medical journal articles. (All articles are on the subject of functional headache and appear after 1982 in such journals as the Journal of the American Medical Association, The Lancet, The New England Journal of Medicine and Headache.) The analysis is organized using the Aristotelian categories of invention (the discovery or creation of arguments), arrangement (their organization in the most persuasive order) and style (including such matters as the use of the passive voice and the avoidance of figurative language). The result of the analysis is a comprehensive inventory of strategies medical authors use in order to influence their peers. The inventory provides a vocabulary and a procedure for analysis of medical rhetoric in general; that is, it goes some way to enabling a medical metadiscourse. The analysis further suggests that rhetorical studies, as a discipline, has much to contribute to medicine's project of examining its own assumptions and scrutinizing its own dominant paradigm. Identifying rhetorical strategies at work in medical journals is one way to articulate medical values and to understand them as instruments of action within the profession.

Authorship↗
PubMed1996

Information as a basic property of the universe.

A theory is proposed which considers information to be a basic property of the universe the way matter and energy are. Operationally--just as energy is defined in terms of its capacity to perform work--so is information defined in terms of its capacity to organize a system. Pure energy can perform no 'useful' (entropy reducing) work without a concomitant input of information. Conversely, all expenditures of energy lead to a reorganization of the universe, hence to a change in its information status. Energy and information are interconvertible; physicists have been able to ignore the information parameter principally for two major reasons. First, historically, just as there was no need to define energy prior to the advent of increasingly complex, powered machinery and cannons (Galileo was a military engineer), so was there no need until the 20th Century to define information. It was the telephone engineers who first preoccupied themselves with developing a theory of information. The second reason is that physicists invented accounting devices such as potential energy and entropy to explain the apparent disappearance of energy yet maintain the law of the conservation of energy. The proposed theory would consider that what is conserved is the sum of information and energy. The mathematical relationship between information and entropy is provided by the equation: I = (Io)e-S/k while the conversion of energy into information involves the relationship: 1 J/degree K = 10(23) bits (approximately) Acceptance of the theory would require paradigm shifts in a number of interrelated areas.

Information Theory↗
PubMed1984

Evolution of myelin sheaths: both lamprey and hagfish lack myelin.

Modern views of agnathan phylogeny consider Petromyzoniformes and Myxiniformes to belong to distinct classes that diverged from a common ancestor at a remote period, perhaps in the lower Cambrian, greater than 600 million years ago. Both are more primitive than elasmobranchs, holocephalans and bony fishes. Myelin is well developed in elasmobranchs and other fishes but was reported to be lacking in the spinal cord of lampreys. In order to search further for possible early myelin in some part of the nervous system of one of the agnathan stems, or for further evidence that it first appeared in chondrichthians, we extended the sampling to many parts of the brain and cord of hagfish. Transmission electron microscopy was used as a nearly ideal criterion. We find no trace or forerunner of the spiral, multilaminate glial wrapping. Many axons are embedded within one or more glial cells, like unmyelinated fibers in other vertebrates, or lie contiguously in bundles without an obviously complete glial investment. True myelin must be presumed to have been invented within the vertebrates, in ancestors of the living cartilaginous fishes after the agnathans branched from the vertebrate stem.

Animals↗
PubMedDate not supplied

Diagnostic accuracy would be improved by developing more categories of "non-disease".

Studies on the ways in which doctors think have shown the importance of intuitive processes in the formulation of a diagnosis. They have also suggested that intuitively generated diagnoses are used to aid the memory of relevant clinical facts during a clinical consultation. Only some symptoms and signs can be ordered into or subsumed under a diagnostic label. Others, which have not been thought of as constituting a disease, will tend to be lost from memory. If a diagnosis were to be thought of, not as the label of a disease but as a mental construct by means of which data are ordered and remembered, that is, as an invention whose utility is to be judged by the degree to which clinical thinking is facilitated, it would become reasonable to develop diagnoses to cover larger areas of clinical phenomenology. Some examples of the usefulness of such diagnoses of "non-disease" are given ant it is suggested that clinical thinking might be improved by the wider use of the concept.

Diagnosis↗
PubMed1981

Dynamic electrocardiography V. The "imaginary cardiac vector" hypothesis: experimental evaluation.

This paper experimentally evaluates the "imaginary cardiac vector" hypothesis, that the cardiac vector is not a real vector. We have previously shown on theoretical grounds that the basis of the cardiac vector is invalid in that Einthoven used scalar, not vector, procedures. Attempts by subsequent workers to compensate for the theoretical flaws have not succeeded. The concept of the "cardiac vector" which they have invented has the dimensions of an imaginary entity. Experimental measurement of isopotential maps derived from dipoles in a volume conductor demonstrates that these dipoles do not summate vectorially. Isopotential maps of the thoracic surface confirm that this applies to the human ECG. An imaginary "man-frog" cardiac vector loop is demonstrated using a lead from a man and a lead from a frog. This illustrates that the "imaginary cardiac vector" is a tenable concept. Finally, a crucial test of the hypothesis is reported which demonstrates that exercise causes deviations of the so-called cardiac vector in opposite directions, simultaneously, in different VCG lead systems. Since a physical entity can only be in one place and more in one direction at a particular instant, this experiment invalidates the "real cardiac vector" hypothesis. This strongly suggests that the cardiac vector is a brilliant, but imaginary, construction with immense clinical value, especially in the interpretation of the sequence of depolarization. Nevertheless, it obstructs analysis of the real basis of the electricity of the heart.

Animals↗
PubMed1985

History of microwave electron linear accelerators for radiotherapy.

Some of the far reaching contributions of Henry S. Kaplan are described which helped launch the development, improvement, and widespread use of microwave electron linear accelerators in radiotherapy. These are presented in historical relationship to the fundamental inventions and developments upon which modern medical accelerator technology is based.

England↗
PubMed1992

Does improved depth dose characteristics and treatment planning correlate with a gain in therapeutic results? Evidence from past clinical experience using conventional radiation sources.

Experience with the use of external beam conventional radiation over a period of several decades has shown that in every instance where there has been a major advance in the physical delivery of radiation to the tumor (beam energy and characteristics and precise tumor dose delivery) there has been a corresponding major improvement in the treatment results. The advent of megavoltage sources following the invention and use of Cobalt 60 and medical linear accelerator units during the late 1940's and early 1950's and their major impact on tumor control and patient survival in solid tumors such as carcinoma of the prostate, Hodgkin's Disease, head and neck tumors and cancer of the cervix are being discussed. Most recently, the use of computerized tomography and computer systems for treatment planning is likely to show a further improvement in the therapeutic results.

Humans↗
PubMed1996

Academic research: policies and practice.

The Bayh-Dole Act of 1980 allowed universities in the US to own and manage inventions obtained using federal funds. This Act laid the foundation for university technology transfer activities in most major research universities of the country. Consequently, the interaction between universities and industry has increased, and so has the sophistication in university intellectual property management. UIC's model for managing its intellectual property is efficient and successful, and is the one increasingly used by university technology transfer offices. The model deals with all aspects of UIC's intellectual property: disclosure, protection, marketing, negotiating and licensing, as well as intellectual property provisions in UIC's research agreements, material transfer agreements, option agreements, licensing agreements and others. In a pioneer effort, UIC has developed a policy on contracts for collecting natural product samples for drug discovery which includes royalty sharing and other important provisions. Accompanying this policy we have also drafted a standard contractual agreement for collectors.

Authorship↗
PubMed1994

Studies of fluid transport in porous rocks by echo-planar MRI.

Attempts to quantify the permeability constant that appears in Darcy's equation in terms of the porosity, tortuosity and surface area have been made by Kozeny and Carman. These results in turn have been translated by Seevers into expressions involving spin-lattice relaxation times. When this work was done originally in the mid-1960s, NMR imaging and spatially localised T1 maps had not been invented. Therefore, bulk T1 average values were used and it is not surprising to see substantial deviations from predicted permeabilities in bore core material. In this paper we re-examine the Kozeny-Carman and Seevers theories in the light of new techniques development for the localised measurement of both T1 maps and fluid velocity maps. New results show spatially correlated T1 and flow maps obtained from Bentheimer sandstone samples. These are discussed in terms of a localised permeability constant. By this means we show that the relationship between T1 and permeability does not hold at the local level for isolated pixels within a larger specimen.

Echo-Planar Imaging↗
PubMed1989

John MacWilliam, evolutionary biology and sudden cardiac death.

Sudden death is frequently of cardiac origin, and its most common electrophysiologic mechanism is ventricular fibrillation. The concept that sudden death in human beings is due to ventricular fibrillation was first proposed by MacWilliam exactly 100 years ago, well before the electrocardiogram was invented. To conduct his experimental work, MacWilliam devised methods that laid the foundations for modern cardiac research and that provided the first comprehensive approach to successful cardiopulmonary resuscitation. He recognized the role of the autonomic nervous system in modulating both the mechanical and the electrical properties of the heart, and was the first to suggest that this effect had a role in the genesis of sudden death. On the centennial of his theory of sudden death, MacWilliam's concepts are reviewed in the context of the effect of Darwinian influence on British physiology. It is suggested that his theorem was based on both sound experimental data and comparative physiology, drawing on the new evolutionary principle of similar structure and function in the hearts of various species. MacWilliam's basic physiologic concepts have survived intact for a century, greatly influencing more than three generations of research and practice in clinical cardiology.

Animals↗
PubMed1991

Arthroscopic laser surgery and suturing for temporomandibular joint disorders: technique and clinical results.

A new surgical technique has been developed to combine arthroscopic laser surgery with suturing to be used clinically in the treatment of temporomandibular joint disorders. This new technique involves the use of a recently invented double-channel cannula needle scope to visualize the lesion. Subsequently, we combined Nd-YAG laser with suturing in the cavity in order to treat the area around the intraarticular wall. The primary use of arthroscopic laser surgery is for treatment of lesions in the inner wall of the joint cavity. In this article, we give an outline of both the arthroscopic laser surgery and the arthroscopic suturing as well as the clinical, postoperative results of these cases.

Adult↗
PubMed1995

Genotypic selection of mitochondrial and oncogenic mutations in human tissue suggests mechanisms of age-related pathophysiology.

The invention of the polymerase chain reaction (PCR) has facilitated the development of a new class of assays to quantify human somatic mutations in vivo, based on genotypic selection of mutants at the DNA level rather than phenotypic selection of mutants at the cell level. Use of these assays has provided new perspectives on the timing, location and distribution of somatic mutagenesis in mitochondrial genes and in oncogenes of the aging human body. This descriptive information has led to the inference and development of new models for age-related pathophysiology and oncogenesis. Mutations of mitochondrial genes rise rapidly with age to frequencies a thousand fold higher than those of nuclear genes. Genotypic selection analysis has revealed that mitochondrial mutations accumulate predominantly in non-mitotic cells whose age-dependent loss is associated with pathology. Random mitochondrial mutation is most likely to inactive Complex I, a deficiency of which induces mitochondrial superoxide formation and cell death. Genotypic selection of oncogenic mutations at the BCL2 and p53 loci has revealed that the cell specificity of oncogenic mutations in persons without cancer correlates well with sites of tumor origin, indicating that cells bearing such mutations are the likely precursors of future tumors. Quantitative variation in human BCL2 mutation frequency is extensive, and BCL2 mutation frequency rises with age, concordant with increased risk for lymphoma. The clonality and persistence of BCL2 mutations suggests two specific testable mechanisms of lymphomagenesis. BCL2 mutation frequency rises in persons exposed to cigarette smoke, and more p53 mutations occur in skin exposed to sunlight than in unexposed skin. Thus, in addition to their likely relevance to future cancer risk, the dose-response relationship between exposure and oncogenic mutations indicates promise for their future use as in vivo biodosimeters of human exposure to carcinogens.

Aging↗
PubMed1996

The copper kettle: a historical perspective.

Until 1952, the administration of inhaled volatile anesthetics was inexact because vaporizers in general use were not calibrated for either concentration or volume of vapor produced. These devices diverted a variable portion of fresh gas flow either through or over the liquid to be vaporized, but they lacked vernier or fine control. Therefore, changes in the concentration of the anesthetic vapor were not easily controlled. Dr. Lucien E. Morris standardized the administration of volatile anesthetics with his invention of the Copper Kettle, which produced known volumes of saturated vapor, then diluted to calculated concentrations necessary for anesthesia. To achieve this, modifications had to be made in the liquid container, circuit design, and vaporizing surfaces in use at the time. Morris' design incorporated a separately metered flow of carrier gas through the vaporizer to produce known volumes of saturated vapor for introduction into the fresh gas flow delivery.

Anesthesiology↗
PubMedDate not supplied

A simple method for cryopreservation of purified adult pig pancreatic cells.

Cryopreservation of islet cells may benefit many aspects of islet transplantation including storage, transport of islets, immunomodulation, reduction of the exocrine contaminants. Isolation and purification of islets from large mammalian pancreases have been encountered by many problems. We reported an autodigestion method for preparation of adult pig pancreatic cells. In this paper, we describe a newly invented simple method for cryopreservation of purified adult pig pancreatic cells. The viability and function of islet cells before (precryo.) and after (postcryo.) the cryopreservation procedure were compared. Islet cell harvested by the autodigestion method were suspended in cryoprotectant "Cell banker." A biofreezing vessel "Bicell" containing a cryogenic vial with cell suspension was frozen at -80 degrees C. After 4 wk, the cryogenic vial was rapidly thawed at 37 degrees C water, the islet cells were washed and cultured for overnight. Number of dithizone-stained precryo. and postcryo. cells were 1.71 +/- 0.5 x 10(5) and 1.75 +/- 0.98 x 10(5) cells/pancreas respectively; therefore, the viability was 99%. Insulin release following high and low concentrations of glucose in precryo. (12.02 +/- 3.63 ng/ml: low-glucose, 9.81 +/- 3.59 ng/ml: high glucose) and precryo. (5.57 +/- 4.03 ng/ml: low-glucose, 10.24 +/- 8.88 ng/ml: high glucose) cells showed a marked improvement in response in postcryo. cells. The insulin content of precryo. and postcryo. cells were 914.4 +/- 277.4 and 93.6 +/- 15.4 ng/ml, respectively. This simple and efficient cryopreservation protocol may be applied for a large-scale storage of adult pig islet cells to establish an islet bank for transplantation.

Age Factors↗
PubMed1994

Testing the quality of electron microscope mapping data for DNA molecules with sequence-specific ligands.

A procedure for the testing of Electron Microscope (EM) mapping data for DNA molecules with site-specific bound ligands is suggested. The difficulty of distinguishing DNA molecule ends on electron micrographs indicates that their true orientations are not known. This in turn presents problems in obtaining correct maps relating to their alignment, and complicates checking the maps' validity. For these reasons a computer simulation of the EM study of double-stranded DNA molecules with site-specific bound ligands was carried out. The knowledge of the true orientations of the simulated DNA molecules allowed us to examine their final orientations after alignment. We used the number of improper-oriented molecules as the quantitative measure of the map quality. Detailed investigation based on this parameter permitted us to invent the criterion for the map validity, and to suggest the procedure for the testing of alignment of real DNA molecules. This procedure implies multiple randomization of initial orientations of the DNA molecules and minute analysis of the final maps. Most of the molecular, statistical and experimental parameters inherent to EM investigation of site-specific binding, such as the number of specific binding sites (N), the mean number of bound ligands (A), the length of the DNA molecules (L), the specific/non-specific ratio of binding (K), together with the standard deviation of DNA molecule lengths (HL) were tested for their influence upon the quality of EM mapping data. An empirical equation for the ultimate values of these parameters has been found, allowing us to predict the success of EM mapping.

Algorithms↗