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Biomedical subjects

T W O'Rourke

Publications and source records attributed to T W O'Rourke.

At least 19 recordsLinked to original sources
PubMed2001

Heterologous expression and properties of the gamma-subunit of the Fe-only hydrogenase from Thermotoga maritima.

Thermotoga maritima is a hyperthermophilic bacterium that contains a complex, heterotrimeric (alpha(beta)gamma) Fe-only hydrogenase. Sequence analysis indicates that the gene encoding the smallest subunit (gamma), hydC, contains a predicted iron-sulfur cluster binding motif. However, characterization of the native gamma-subunit has been hampered by interference from and the inability to separate intact gamma-subunit from the other two subunits (alpha and beta). To investigate the function and properties of the isolated gamma-subunit, the gene encoding HydG was expressed in Escherichia coli. Two forms of the recombinant protein were obtained with molecular masses of 10 and 18 kDa, respectively. Both contained a single [2Fe-2S] cluster based on metal analysis, EPR and UV-visible spectroscopy. NH2-terminal sequencing revealed that the 10 kDa protein is a truncated form of the intact gamma-subunit and lacks the first 65 amino acid residues. The midpoint potential of the 18 kDa form was -356 mV at pH 7.0 and 25 degrees C, as measured by direct electrochemistry, and was pH dependent with a pK(ox) of 7.5 and a pK(red) of 7.7. The oxidized, recombinant gamma-subunit was stable at 80 degrees C under anaerobic conditions with a half-life greater than 24 h, as judged by the UV-visible spectrum of the [2Fe-2S] cluster. In the presence of air the protein was less stable and denatured with a half-life of approx. 2.5 h. The recombinant gamma-subunit was electron transfer competent and was efficiently reduced by pyruvate ferredoxin oxidoreductase from Pyrococcus furiosus, with a Km of 5microM and a Vmax of 9 U/mg. In contrast, native T. maritima hydrogenase holoenzyme and its separated alpha-subunit were much less effective electron donors for the gamma-subunit, with a V(max) of 0.01 U/mg and 0.1 U/mg, respectively.

Amino Acid Sequence↗
PubMed1996

Kids at increased risk in a changing environment--challenges, responses, and opportunities.

These are only a few of the possible examples of challenging our thinking and approaches which guide our actions. As previously mentioned, challenges inevitably are accompanied by opportunities which are essential not only to survive but thrive. In the year ahead, I challenge each of you on a personal level, and ASHA at an organizational level, to meet both imposed and self-initiated challenges. The results will be positive, both for you and ASHA, and especially for our chief concern, the children who bind all of us together and our future.

Adolescent↗
PubMed1991

Effects of cost sharing in health insurance on disability days.

We assess how cost sharing for medical services affects restricted activity days (RADs) and work loss disability days (WLDs), using data from a controlled experiment. We grouped the experimental insurance plans into four categories, one providing free care and the other three requiring varying amounts of cost sharing. RADs per person per year decreased by one to two days with greater cost sharing, with the strongest effects among those of average or poor health status, especially the non-poor. Unlike RADs, WLDs showed no systematic differences by plan.

Absenteeism↗
PubMed1989

Ethical issues in research and publication.

Ethical considerations inherent in the process of research and publication represent one issue of particular concern to professionals. Members of a profession usually are guided by a code of ethics that specifies standards for practice. However, rarely do professional preparation programs sufficiently prepare students to deal with the concerns associated with research and professional publication. The authors address three specific areas of concern for health educators: the student-professor relationship, joint authorship, and ethics in publishing. Potential problems are discussed, and implications for the profession are cited.

Authorship↗
PubMed1985

Detection of neutral amino acid substitutions in proteins.

The field of biochemical genetics relies heavily upon the detection by electrophoresis of genetically determined variants of proteins. Most of these variants differ by substitutions that involve charged amino acids. Genetic variants of another large class, ones that involve substitutions among neutral amino acids, are not easily detected and are often ignored. Ampholyte isoelectric focusing in some cases can separate proteins indistinguishable by standard electrophoresis, including genetic variants of mouse hemoglobins that differ only by neutral amino acid substitutions. A revolutionary variation of isoelectric focusing, in which gradients covering a small pH range are fixed into place in a polyacrylamide gel, provides greater resolution of these nearly identical proteins. Mouse hemoglobin tetramers that differ only by the substitution of alanine for glycine in the alpha-globin chains are resolved by several millimeters with the new technique; by comparison, these tetramers are imperfectly resolved on a standard pH 7-9 isoelectric focusing gel. This improved technique of isoelectric focusing was used to identify a variety of previously unreported genetic variants of mouse hemoglobin alpha chains. Immobilized gradients tailored to the requirements of the proteins being analyzed will extend greatly the ranges of protein variations that can be easily recognized for diverse applications, including genetic quality-control analyses and in studies of genetics, mutagenesis, and evolution.

Amino Acid Sequence↗
PubMed1985

Enriching professional preparation in school health through international study.

This article describes how to develop, market, implement, and evaluate an international health education travel study course. The experiences described reflect an international travel study tour of England and Scotland conducted by the authors with 25 undergraduate and graduate students. The trip enhanced both the appreciation and professional knowledge of the students of a variety of perspectives in the health area. International study provides unique opportunities for student development and contributes significantly to the quality of professional preparation of school health personnel. These experiences complement traditional professional preparation programs and can result in improved health instruction and health services in schools.

Cross-Cultural Comparison↗
PubMed1978

Comparison of task performance of master's and bachelor's degree social workers in hospitals.

The purpose of this article is to report on the current practice of social work in the hospitals in a 16-county area of central Illinois. A comparison was made between the master's degree workers' and bachelor's degree workers' perceived importance of selected social service tasks and their view of the frequency with which these tasks were carried out. The data indicate no significant difference between the attitudes of master's degree workers and bachelor's degree workers toward the importance of the tasks; however, there were several significant differences in the frequency with which some of these tasks were performed. The implications of these findings to social work practice and education are discussed.

Education, Graduate↗
PubMed1976

Knowledge, behavior, and attitudes of sixth-grade students toward family life education.

Although certain exceptions may be noted with respect to sex and type of school, generally lower socioeconomic students obtained lower mean scores on the knowledge and attitude sections of the survey instrument than their counterparts from the higher economic strata. Disadvantaged children from lower socioeconomic levels are reared in an atmosphere hardly conducive to study. Their homes are overcrowded; the children are often hungry, obtain insufficent rest, and possess little interest or motivation for the future--they just live for today. The lower socioeconomic child suffers most when he comes to school. His experiences in living have not prepared him for the demands of the typical school. Shaped by his environment, seeing himself as a person of little worth, he is called upon to conform and communicate. His value system that was bred in deprivation shows sharp contrast to the established "middle class" value system held by the school. Furthermore, disadvantaged children enter school with habits and attitudes that may conflict with many of the traditional modes of teaching. They have had few opportunities to learn the relationship between effort and achievement or to observe that learning has its own reward. Educators have a responsibility to provide the best type of family life education program to meet the needs of all youth. Innovative and challenging ways must be found to make family life education programs relevant to all socioeconomic strata. It would appear essential that educators should possess a thorough knowledge of the economic, social, and cultural conditions that exist in the area in which the educational process is to be conducted.

Attitude↗