Biomedical subjects

R Teeter

Publications and source records attributed to R Teeter.

8 recordsLinked to original sources

PubMed2001

The incidence of tuberculosis in drug users with small tuberculin reaction sizes.

SETTING: In persons infected with the human immunodeficiency virus (HIV), a decreased tuberculin reaction cut-point of > or = 5 mm induration is recommended. OBJECTIVE: To determine tuberculosis risk in non-anergic HIV-infected persons with 5-9 mm tuberculin reactions. DESIGN: A prospective study with semi-annual tuberculin and anergy testing, HIV antibody and T cell subset assays, and active surveillance for tuberculosis. RESULTS: Participants were 572 HIV-seronegative and 241 HIV-seropositive non-anergic drug users. No tuberculosis occurred in HIV-seronegative persons. Tuberculosis incidence among HIV-seropositive drug users was 3.3, 7.7, 0, and 0.34 per 100 person-years in those with tuberculin reaction sizes of > or = 10 mm, 5-9 mm, 1-4 mm, and 0 mm, respectively, and was significantly increased in persons with 5-9 mm induration compared with those with 0-4 mm induration (rate ratio 27.7, 95%CI 2.9-268). Among persons with reaction sizes of 5-9 mm, tuberculosis occurred exclusively in those with CD4+ lymphocyte counts <500/mm3 at the time of their 5-9 mm tuberculin reactions. CONCLUSION: HIV-infected persons with tuberculin reaction sizes of 5-9 mm are at increased risk for tuberculosis compared to non-anergic persons with smaller (0-4 mm) reaction sizes. However, this increased risk may be limited to those with low CD4+ lymphocyte counts at the time of tuberculin testing.

Adult↗

PubMed1999

Self-assessment of tuberculin skin test reactions by drug users with or at risk for human immunodeficiency virus infection.

SETTING: Self-assessment of tuberculin test results, if accurate, could enhance tuberculosis screening efforts by reducing the need for follow-up visits for skin test reading. We investigated tuberculin test self-assessment in a longitudinal study of tuberculosis infection among drug users. OBJECTIVE: To determine the accuracy of tuberculin reaction self-assessment by drug users at high risk for tuberculosis infection. DESIGN: Two readings were compared of the same skin test, performed 48-72 hours after placement: 1) self-assessment using a simple yes-no approach to induration, versus 2) trained examiner reading. Self-assessments were performed immediately prior to trained examiner readings. RESULTS: Participants were 137 human immunodeficiency virus (HIV) seropositive and 344 HIV-seronegative current and former drug users. Ten per cent (35/344) of reactions read by participants as 'flat' were read by trained examiners as > or =5 mm (54% of which were > or =10 mm). Twenty-three per cent (19/82) of reactions read by trained examiners as > or =10 mm and 32% (35/110) of reactions read by trained examiners as being > or =5 mm were self-read by participants as 'flat'. Sensitivity (0.68) and specificity (0.83) of self-read tuberculin reactions were sub-optimal. Inter-reader reliability was poorer between participants and trained examiners than between trained examiners. CONCLUSION: Self-assessments of tuberculin skin test responses by drug users with or at risk for HIV infection are not reliable.

Adult↗

PubMed1995

Pre-school responses to the 19th-century youth crisis.

The travails of 19th-century urban youth were a precondition to the invention of modern adolescence and the rise of the modern secondary school. These travails led to a child-saving movement during the last century aimed at taking youth off the streets, putting them in schools, stretching out the normal home-leaving age from 14 to 18 and, in general, prolonging a developmental period. While the ultimate solution to the youth crisis would be the creation of the modern school, other solutions-less expensive, less innovative, and much less effective-were tried first. As unproductive as these attempts were, they nevertheless underscore an increased readiness on the part of the American people to solve the youth problem, not out of egalitarianism or increased moral acuity, but out of social necessity.

Adolescent↗

PubMed1992

Development of countermeasures for medical problems encountered in space flight.

By the turn of this century, long-duration space missions, either in low Earth orbit or for got early planetary missions, will become commonplace. From the physiological standpoint, exposure to the weightless environment results in changes in body function, some of which are adaptive in nature and some of which can be life threatening. Important issues such as environmental health, radiation protection, physical deconditioning, and bone and muscle loss are of concern to life scientists and mission designers. Physical conditioning techniques such as exercise are not sufficient to protect future space travellers. A review of past experience with piloted missions has shown that gradual breakdown in bone and muscle tissue, together with fluid losses, despite a vigorous exercise regimen can ultimately lead to increased evidence of renal stones, musculoskeletal injuries, and bone fractures. Biological effects of radiation can, over long periods of time increase the risk of cancer development. Today, a vigorous program of study on the means to provide a complex exercise regimen to the antigravity muscles and skeleton is under study. Additional evaluation of artificial gravity as a mechanism to counteract bone and muscle deconditioning and cardiovascular asthenia is under study. New radiation methods are being developed. This paper will deal with the results of these studies.

Aerospace Medicine↗

PubMed1990

Life sciences issues affecting space exploration.

The U.S. space program is undertaking a serious examination of new initiatives in human space exploration involving permanent colonies on the Moon and an outpost on Mars. Life scientists have major responsibilities to the crew, to assure their health, productivity, and safety throughout the mission and the postflight rehabilitation period; to the mission, to provide a productive working environment; and to the scientific community, to advance knowledge and understanding of human adaptation to the space environment. Critical areas essential to the support of human exploration include protection from the radiation hazards of the space environment, reduced gravity countermeasures, artificial gravity, medical care, life support systems, and behavior, performance, and human factors in an extraterrestrial environment. Developing solutions to these concerns is at the heart of the NASA Life Sciences ground-based and flight research programs. Facilities analogous to planetary outposts are being considered in Antarctica and other remote settings. Closed ecological life support systems will be tested on Earth and Space Station. For short-duration simulations and tests, the Space Shuttle and Spacelab will be used. Space Station Freedom will provide the essential scientific and technological research in areas that require long exposures to reduced gravity conditions. In preparation for Mars missions, research on the Moon will be vital. As the challenges of sustaining humans on space are resolved, advances in fundamental science, medicine and technology will follow.

Adaptation, Physiological↗

PubMed1988

Coming of age on the city streets in 19th-century America.

Broken free of any semblance of family control or community restraints, thousands of American youth roamed entirely at will throughout the cities of 19th-century America and supported themselves alternately from the legitimate street trades and from outright thievery. The invention of modern adolescence was partially a response to this neglected condition of urban youth.

Adolescent↗

PubMed1988

The travails of 19th-century urban youth as a precondition to the invention of modern adolescence.

One of the factors leading up to the "invention" of modern adolescence was what reformers saw as the corruption of youth by the city. It was the plight of these youth--all too visible to reformers, intellectuals, opinion makers, and trend setters--which set the stage for a child-saving movement during the last century aimed at taking youth off the streets, putting them in schools, stretching out the home-leaving age from 14 to 18, and in general, prolonging a developmental period.

History, 19th Century↗

PubMed1987

Scientific origins of adolescent sport.

The prominence of sport in the American secondary school curriculum owes much to 19th-century child development theories, the most prominent of which (Von Baer's Law) originated in embryology, the forerunner of modern psychology. Von Baer's Law held that embryonic development formed a condensed record of human development, that the embryo in the womb represented in miniature the overall organic evolution of man. The "law" held that youth passed through the same developmental gradations ontogenetically that the human race passed through phylogenetically; that youth repeated in their development approximately the development, from barbarity to civilization, of the human race. Indeed, they stood at a primitive developmental level and simply passed through a stage the human race had passed through thousands of years earlier. Von Baer's Law became a scientific rationale for sport in American schools, most particularly, football, which was believed to be spirited enough to "satisfy the racial claim" and mitigate against antisocial aggressiveness.

Adolescent↗