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Biomedical subjects

Gary D Byrd

Publications and source records attributed to Gary D Byrd.

10 recordsLinked to original sources

The synthesis and biological evaluation of dopamine transporter inhibiting activity of substituted diphenylmethoxypiperidines.

The synthesis of potent 4-aryl methoxypiperidinol inhibitors of the dopamine transporter is described. Symmetrical para substituents of the benzene rings are important for high potency in binding to the dopamine transporter. 4-[Bis(4-fluorophenyl) methoxy]-1-methylpiperidine has an IC50 of 22.1+/-5.73 nM and increases locomotor activity in mice.

Dopamine Plasma Membrane Transport Proteins↗

Effect of creatinine and specific gravity normalization techniques on xenobiotic biomarkers in smokers' spot and 24-h urines.

Renal excretion mechanisms are xenobiotic-specific; therefore, accurate exposure assessment requires an understanding of relationships of xenobiotic biomarker concentration and excretion rate to urine flow, specific gravity and creatinine concentration. Twenty-four-hour urine collection for xenobiotic exposure assessment is considered the "gold standard" procedure. Random spot-urine collection is convenient and minimizes subject compliance concerns but requires that normalization techniques be employed to account for diuresis and diurnal variation in xenobiotic biomarker excretion. This paper examines and makes recommendations concerning normalization techniques and conditions under which spot-urine results most accurately reflect 24-h urine results. Specific gravity, creatinine, and xenobiotic biomarkers were determined in smokers' spot and 24-h urines. Normalization techniques were applied, variance-component analyses were performed to estimate variability, spot urines were pooled mathematically to simulate 24-h urines and analyses of variance were performed to evaluate spot urines' ability to reflect 24-h urine concentrations. For each xenobiotic biomarker concentration, log-linear relationships were observed with urine flow, specific gravity, and creatinine. For most xenobiotic biomarker excretion rates, log-linear relationships were observed with urine flow; creatinine, however, was unaffected by urine flow. The conventional creatinine ratio-normalization technique demonstrated greater variability (within-day, between-day and between-subject) than other normalization techniques. Comparisons of simulated 24-h urines to spot urines suggest that spot-urine collection be performed only between 2 p.m. and 2 a.m. and that the modified specific-gravity-adjusted-creatinine ratio-normalization technique and the creatinine-regression normalization technique yield the best agreement between spot- and simulated 24-h urine results.

Biomarkers↗

Evaluating the effectiveness of clinical medical librarian programs: a systematic review of the literature.

OBJECTIVE: This study was undertaken to determine if a systematic review of the evidence from thirty years of literature evaluating clinical medical librarian (CML) programs could help clarify the effectiveness of this outreach service model. METHODS: A descriptive review of the CML literature describes the general characteristics of these services as they have been implemented, primarily in teaching-hospital settings. Comprehensive searches for CML studies using quantitative or qualitative evaluation methods were conducted in the medical, allied health, librarianship, and social sciences literature. FINDINGS: Thirty-five studies published between 1974 and 2001 met the review criteria. Most (30) evaluated single, active programs and used descriptive research methods (e.g., use statistics or surveys/questionnaires). A weighted average of 89% of users in twelve studies found CML services useful and of high quality, and 65% of users in another overlapping, but not identical, twelve studies said these services contributed to improved patient care. CONCLUSIONS: The total amount of research evidence for CML program effectiveness is not great and most of it is descriptive rather than comparative or analytically qualitative. Standards are needed to consistently evaluate CML or informationist programs in the future. A carefully structured multiprogram study including three to five of the best current programs is needed to define the true value of these services.

Clinical Medicine↗

Liquid chromatographic/tandem mass spectrometric method for the determination of the tobacco-specific nitrosamine metabolite NNAL in smokers' urine.

A specific and rapid liquid chromatographic/tandem mass spectrometric (LC/MS/MS) method was developed and validated for NNAL, a metabolite of the tobacco-specific nitrosamine metabolite NNK. The metabolite was detected in smokers' urine with a limit of quantitation (LOQ) of 20 pg ml(-1) and a linear range up to 1000 pg ml(-1). The method features a single solid-phase extraction step and MS/MS monitoring following electrospray ionization. Fragmentation pathways for the protonated molecular ion are proposed. The sample preparation is simpler than that for gas chromatographic methods reported in the literature and maintains sensitivity adequate for determining NNAL in smokers' urine. By using enzyme hydrolysis to determine total NNAL in urine, the amount of NNAL-glucuronide was calculated. A standard pooled smokers' urine sample used for development gave values of 176 +/- 8 pg ml(-1) free NNAL and 675 +/- 26 pg ml(-1) total NNAL following enzyme hydrolysis. The method was applied to a group of seven smokers; the free NNAL level for the group was 101-256 pg ml(-1) with NNAL-glucuronides at 247-566 pg ml(-1). The ratio of conjugated to free NNAL was in the range 0.98-2.95. The variability in total daily amount of NNAL excreted (ng per 24 h) had RSDs of 6-21% for free NNAL, 7-22% for conjugated NNAL and 6-20% for total NNAL excreted. When normalized to the number of cigarettes smoked, the amounts of NNAL excreted per cigarette smoked were in the range of amounts of NNK yields reported for cigarettes in the literature.

Adult↗

The Association of Academic Health Sciences Libraries Annual Statistics: an exploratory twenty-five-year trend analysis.

This paper presents an exploratory trend analysis of the statistics published over the past twenty-four editions of the Annual Statistics of Medical School Libraries in the United States and Canada. The analysis focuses on the small subset of nineteen consistently collected data variables (out of 656 variables collected during the history of the survey) to provide a general picture of the growth and changing dimensions of services and resources provided by academic health sciences libraries over those two and one-half decades. The paper also analyzes survey response patterns for U.S. and Canadian medical school libraries, as well as osteopathic medical school libraries surveyed since 1987. The trends show steady, but not dramatic, increases in annual means for total volumes collected, expenditures for staff, collections and other operating costs, personnel numbers and salaries, interlibrary lending and borrowing, reference questions, and service hours. However, when controlled for inflation, most categories of expenditure have just managed to stay level. The exceptions have been expenditures for staff development and travel and for collections, which have both outpaced inflation. The fill rate for interlibrary lending requests has remained steady at about 75%, but the mean ratio of items lent to items borrowed has decreased by nearly 50%.

Annual Reports as Topic↗

The Association of Academic Health Sciences Libraries Annual Statistics: a thematic history.

The Annual Statistics of Medical School Libraries in the United States and Canada (Annual Statistics) is the most recognizable achievement of the Association of Academic Health Sciences Libraries in its history to date. This article gives a thematic history of the Annual Statistics, emphasizing the leadership role of editors and Editorial Boards, the need for cooperation and membership support to produce comparable data useful for everyday management of academic medical center libraries and the use of technology as a tool for data gathering and publication. The Annual Statistics' origin is recalled, and survey features and content are related to the overall themes. The success of the Annual Statistics is evident in the leadership skills of the first editor, Richard Lyders, executive director of the Houston Academy of Medicine-Texas Medical Center Library. The history shows the development of a survey instrument that strives to produce reliable and valid data for a diverse group of libraries while reflecting the many complex changes in the library environment. The future of the Annual Statistics is assured by the anticipated changes facing academic health sciences libraries, namely the need to reflect the transition from a physical environment to an electronic operation.

Annual Reports as Topic↗

Can the profession of pharmacy serve as a model for health informationist professionals?

Pharmacy could serve as a model for the health informationist profession proposed by Davidoff and Florance in their 2000 editorial in the Annals of Internal Medicine. The current training and practice roles for pharmacists suggest a way to prepare health sciences librarians for work with clinical health care teams. The influences that spurred the transformation of pharmacy parallel in many respects those suggesting the need for more information professionals prepared to practice in clinical health care settings. During the same decades that health sciences librarians have been debating and experimenting with new professional roles such as clinical medical librarians, pharmacy has undergone an intensive review of its core values, mission, practice roles, and educational preparation methods. Until recently, most pharmacists graduated from five-year baccalaureate programs preparing them to understand drug products, sources of supply, and effective ways to dispense them to patients as prescribed by physicians. Today, almost all pharmacy students graduate from six-year doctor of pharmacy programs that prepare them to be the primary providers of what their profession calls "pharmaceutical care." The pharmaceutical care model suggests that health information professionals in clinical settings could be educated and trained to provide what we might call health information care.

Humans↗