PubMed HealthSearch

Biomedical subjects

K McCarty

Publications and source records attributed to K McCarty.

17 recordsLinked to original sources

A survey of medical directors of life insurance companies concerning use of genetic information.

Rapid advances in our ability to test persons presymptomatically for genetic diseases have generated increasing concern that genetic information will be abused by insurance companies. Reasoning that the insurance companies may have the strongest interest in using genetic data and that the medical directors of those companies with responsibility for rating applicants would be a good source of information on the use of such data, we conducted a large survey of medical directors of North American life insurance companies. We received responses from 27 medical directors. Our results suggest that (1) few insurers perform genetic tests on applicants, but most are interested in accessing genetic test information about applicants that already exists; (2) the degree of insurers' interest in using genetic test results may depend on the face amount of the policy applied for and on the specificity and sensitivity of the test; (3) many companies employ underwriting guidelines with respect to certain genetic conditions but may not always have specific actuarial data in house to support their rating decisions; (4) a considerable degree of subjectivity is involved in most insurers' rating decisions; and (5) some of the medical directors who responded to our survey are not fully informed about certain basic principles of medical genetics.

Ethics, Medical

A survey of state insurance commissioners concerning genetic testing and life insurance.

Rapid advances in genetic testing have stimulated growing concern about the potential for misuse of genetic data by insurance companies, employers, and other third parties. Thus far, reports of genetically based discrimination in life insurance have been anecdotal. Reasoning that state insurance commissioners were likely to be aware of (1) the extent of current use of and interest in genetic tests by life insurers and (2) consumer complaints about insurance being denied because of genetic condition or because of genetic test results, we conducted a survey of that group. We received responses from 42 of the 51 jurisdictions. Our results suggest (1) that those who regulate the life insurance industry do not yet perceive genetic testing to pose a significant problem in how insurers rate applicants, (2) that life insurers have much legal latitude to require genetic tests, and (3) that so far few consumers have formally complained to commissioners about the use of genetic data by life insurers.

Adult

Ethical issues in the care of cancer patients.

Nearly all the topics considered by medical ethics generally present themselves to those caring for cancer patients. Although most attention may be given to questions of resource allocation and limiting treatment, other issues are of equal importance. Providing respect and compassion for patients may be even more important. The day-to-day treatment of the patient that recognizes the practical autonomy of the patient and legitimizes the patient's involvement in deciding about his or her own care may do more to preserve the integrity of the patient as a person than anything else that happens to someone who accepts the cancer diagnosis. The physician who can accept the patient's judgment and participation and who can help the patient find positive meaning in what can be a personally and socially devastating disease experience has enacted a highly laudatory ethical standard of patient care.

Beneficence

Correlation between Korotkoff's sounds and ultrasonics of the brachial artery in healthy and normotensive subjects.

The clinical measurement of blood pressure is generally obtained by auscultation for Korotkoff's sounds over the brachial artery using a sphygmomanometer and cuff. Real-time two dimensional ultrasound and Doppler techniques were used to study the brachial artery movements and blood flow patterns during these pressure measurements. Simultaneous recordings of Korotkoff's sounds were obtained. A strong correlation in time was demonstrated between Korotkoff's five phases, brachial artery wall movements and specific blood flow patterns. The evidence largely supports what to date has been speculation as to the origin of Korotkoff's sounds in that Korotkoff's phases 1 and 3 appear to be produced by vigorous arterial wall motion and phase 5 by cessation of this movement. Phase 2 is produced by blood flow disturbance. Furthermore, the lack of correlation between phase 4 and any specific vascular event may go some way to explaining why in clinical practice phase 5 readings are now preferred for diastolic pressure.

Adult

Pathologic considerations in the high-risk breast patient.

An understanding of the spectrum of benign breast changes is necessary to optimize diagnosis and treatment. To evaluate the relative risk for developing cancer with benign breast lesions, each of the entities included in the category of benign breast conditions is discussed individually.

Adenofibroma

Purification and characterization of mouse uterine estrogen receptor under conditions of varying hormonal status.

Mouse uterine estrogen receptor (ER) was purified about 11,000-fold from normal mouse uteri by affinity chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified ER demonstrated a major component of 65,000 mol wt with minor fragments of the 54,000- and 37,000-dalton species, as judged by affinity labeling with [3H]tamoxifen aziridine and immunodetection with an ER monoclonal antibody (H-222). The minor fragments were not detected with additional monoclonals (H-226 or D-547), which recognize different domains on the ER molecule. Two-dimensional gel electrophoresis revealed that the major component with a mol wt of 65,000 had a pI of about 6.5. The 54,000- and 37,000-dalton components had similar pI values. Saturation binding and Scatchard plot analysis of purified ER yielded one class of binding sites with an apparent dissociation constant of about 1.4 nM. Changes in the hormonal status resulted in changes in the size of the ER even in the presence of molybdate and leupeptin.

Animals

Measurement of volume flow in the human common femoral artery using a duplex ultrasound system.

A duplex ultrasound system was used to measure volumetric flow in the human common femoral artery. The accuracy of the technique was validated using a flow rig. The average resting common femoral artery flow rate in a population of subjects clinically unaffected by peripheral vascular disease was 350 +/- 141 mls min-1. Although mean common femoral artery diameter was greater in males (10 +/- 0.9 mm) than in females (7.8 +/- 0.7 mm) (p less than 0.01), there was no significant difference in resting blood flow. Repeated measurements in individual subjects showed a high variability, largely due to physiological fluctuations (75 percent of total variability). There was a close correlation between volume flow and the reciprocal of pulsatility index (100/PI). In normal subjects 100/PI represents a simpler method of determining individual changes in blood flow. The temporal variations in volume flow during periods of reactive hyperaemia had a characteristic profile, which was dependent on the duration of circulatory arrest. The data derived from the resting hyperaemia flow profile provides normal ranges for future comparison with patients suffering from peripheral vascular disease.

Adult

Metastatic basal cell carcinoma.

Basal cell carcinoma rarely metastasizes. There are over 130 reported cases, 70% of which involve lymph nodes. In many cases a large, chronic, neglected or inadequately treated basal cell carcinoma preceded the metastasis. We report a case in which a basal cell carcinoma of the cheek metastasized to cervical lymph nodes.

Adult

Aspects of the design of performance measuring test objects.

In order for medical ultrasonics to achieve a high and universal standard of systematic and scientific implementation, methods for assessing the imaging performance of scanners must be developed which are both rigorous and simple to use. The difficulty that has been found in this task comes from the complex interaction of the performance parameters. Measurements of parameters should not be presented in mutual isolation. Further, the performance of a scanner, as measured using electronically generated external stimuli, might not be generalised to realistic acoustic situations. If the assessment is to be relevant to the clinical situation these factors must be taken into account. Test objects employing tissue mimicking materials provide the simplest, and possibly the only way to achieving this. In this paper the authors' designs for such test objects together with an indication of a comprehensive test system are presented.

Acoustics

A simple calibration and evaluation phantom for ultrasound scanners.

It is argued that performance measuring phantoms containing tissue mimicking material should be considered as a series of combined test features. Each test feature should be capable of yielding quantitative data if desired and the inclusion of a comprehensive set of such features in a single phantom would allow the mutual interdependence of performance parameters to be assessed. These ideas are demonstrated in scans of several phantoms which utilise new features for measuring grey scale performance and relative beam width orthogonal to the scan plane. The relation of this work to research on low contrast detectability of lesions is discussed.

Biophysical Phenomena

Subchronic administration of caffeine and theophylline in drinking water: effects on rat liver RNA polymerase I activity.

Administration of caffeine or theophylline, 0.2 mg/ml (an average of 20 mg/kg/d) of drinking water, to male CD rats, 2 months of age, over a 15 week period resulted in the elevation of liver RNA polymerase I activity by 2-3 fold as assayed in isolated nuclei. This increase in activity was already apparent by the fourth week of exposure. The changes in RNA polymerase I activity were accompanied by moderate liver hypertrophy.

Animals

Follicle-stimulating hormone-mediated induction of functional luteinizing hormone/human chorionic gonadotropin receptors during monolayer culture of porcine granulosa cells.

The LH/hCG receptor content of porcine ovarian granulosa cells from 1- to 3-mm follicles can be increases to 4--5 times the preculture level during monolayer culture in serum-containing media supplemented with insulin and FSH. The binding of [125I]iodo-hCG declines during the first 2 days of culture, but then uniformly increases through 6 days, achieving a 14- to 15-fold increase relative to the 2-day level under optimal conditions. Analysis of receptor binding by autoradiography indicates that after 2 days, the number of cells specifically binding [125I]iodo-hCG increases significantly during culture, as does the intensity of binding on receptor-bearing cells. Granulosa cells in monolayer culture exhibit heterogeneous receptor induction, indicating that normalized [125I]iodo-hCG binding data cannot be used to estimate receptor concentration per cell. Receptor affinities in the initial and induced populations are identical. LH/hCG receptors induced in granulosa cells during culture are functional, as demonstrated by specific hCG-stimulated progesterone secretion. 17 beta-Estradiol produces a differential effect in vitro, generally increasing [125I]iodo-hCG binding with respect to FSH-induced levels but consistently depressing the subsequent hCG-stimulated steroidogenic response of cells bearing the induced receptor. The porcine granulosa cell monolayer system thus appears to be a useful model with which to study, in vitro, mechanisms of steroid and gonadotropin regulation of granulosa cell differentiation and overall follicular development.

Animals

Evaluation of tympanic membrane thermometer for use with pediatric patients.

To determine if a tympanic membrane thermometer is of benefit on a pediatric unit. Temperature readings using a tympanic membrane thermometer and an electronic thermometer were compared for 295 paired observations. The electronic temperature readings were done by rectal (n = 32), oral (n = 65), and axillary (n = 198) routes. Differences in tympanic and electronic readings were compared by paired t-tests, and the readings were also correlated. The nursing time in seconds was also compared between electronic and tympanic measurements. Parents and nurses rated their opinion of each type of measurement on a 0-5 Likert scale. Nurses rated the patient's response using the same scale. Results indicate that temperature readings differ by an average of .2- .5 degree between tympanic and electronic thermometers. Correlations are statistically significant but of low-to-moderate strength. Parents and nurses did not rate the types of instruments differently. The nurses rated the electronic axillary method as being more acceptable to toddlers. The tympanic membrane measurement took an average of 30-38 seconds less time to take. Tympanic membrane thermometry saves nursing time. Although the correlations were not strong between electronic and tympanic membrane measurements, the tympanic reading was closer to the electronic rectal reading than to axillary or oral readings.

Adolescent