Formalization of the MESF unit of fluorescence intensity

This report summarizes the work performed during the past two years at the National Institute of Standards and Technology (NIST) in the refinement and formal definition of the MESF unit of fluorescence intensity. In addition to the theory underlying the MESF unit, considerations of error analysis are also presented. The details of this work may be found in the three publications of the NIST Journal of Research (www.nist.gov) listed as the references 2-4. The use of the fluorescence intensity unit provides a tool to compare quantitative fluorescence intensity measurements over time and across platforms.

Setting a local research agenda for women's health: The National Centers of Excellence in Women's Health

Although women's health research expanded greatly in the past 10 years, significant gaps in knowledge remain. Prioritization and promotion of research will help assure continuing progress in closing such gaps and improving the health of women. Although a comprehensive agenda for the new millennium has been developed at the national level, the process for establishing a local research agenda is not well defined. The purpose of this study was to describe criteria for and barriers to establishing a local research agenda in women's health. A secondary aim was to describe mechanisms for identifying women's health researchers and for facilitating multidisciplinary research. Directors of Research at National Centers of Excellence in Women's Health (CoEs) (n = 18) were surveyed by mail for this information. The results indicate that the local research agenda should emphasize health issues that are prevalent in women, research that is likely to establish treatment, psychosocial/cultural factors, and quality of life issues. The process of setting a research agenda should include input from the communities served as well as from scientists. Critical evaluation of scientific strengths and weaknesses is an essential preliminary step in prioritizing research opportunities in order to implement and evaluate a research agenda in women's health.

Involving minority and underrepresented women in clinical trials: the National Centers of Excellence in Women's Health

Recent attention to reducing health disparities among population groups has focused on the need to include in clinical studies, especially clinical trials, participants who represent the diversity of the populations to which study results will be applied. While scientists generally applaud the goal of broadening the characteristics of participants in clinical trials, they are faced with multiple challenges as they seek to include historically underrepresented populations in their research. This article examines the historical and sociocultural context of participation by underrepresented groups, especially women and minorities, in clinical trials, identifies major barriers and challenges facing researchers, and suggests strategies for meeting these challenges. The article draws upon the experiences of the investigators affiliated with the National Centers of Excellence of Women's Health (CoEs).

Attenuation of injury due to unilateral renal ischemia: delayed effects of contralateral nephrectomy

The functional abnormalities associated with unilateral postischemic acute renal failure in the rat, as produced by 60 min of complete renal artery occlusion, are influenced by the presence or absence of the contralateral kidney. When the contralateral kidney is removed prior to the ischemia, reflow of blood to the postischemic kidney is more complete. To determine whether this maneuver influenced the ultimate severity of the injury and, if so, to investigate the mechanism by which this occurred, studies were performed conjointly at Tel-Hashomer, Israel, and Chapel Hill, N.C., in uninephrectomized (UNx) and sham-operated (Sh) rats. At Tel-Hashomer, V from UNx rats was nearly double that found in Sh rats at 1 to 3, 3 to 5, and 24 hr after ischemia. By 24 hr, CCr was substantially greater in UNx rats and was similar to that from the nonischemic kidney of Sh rats. Differences in tubular function were also noted. In UNx rats, FENa at 24 hr was significantly less and TCH2O was significantly greater than the corresponding values determined in Sh rats. At Chapel Hill, by 24 hr, RBF and PGCe in UNx rats were significantly greater than the corresponding values in Sh rats, although both were less than values obtained in nonischemic kidneys. In UNx rats, RT and RPG were considerably less than the corresponding values in Sh rats and similar to the values obtained in nonischemic kidneys. Microscopic examination at 24 hr revealed widespread tubular epithelial cell necrosis in Sh rats. In contrast, tubular epithelial cell structures were preserved in UNx rats. These data indicate that substantive differences exist in the response to temporary unilateral renal ischemia, which depend in part on the absence of the contralateral kidney and which result in less severe reduction in RBF and CCr and the preservation of tubular epithelial structure and function.

Structural and functional response of toad urinary bladder to LiCl

The physiological and morphological response of toad urinary bladder was examined during mucosal exposure of LiCl both with and without vasopressin (VP). With 20 or 100 mU/ml of VP in the serosal bath there was a decrease in Jv between the first and second VP stimulation in LiCl-treated bladders (VP20, -14 +/- 6%; VP100, -16 +/- 5%) that was not different from that observed without LiCl (VP20, -8 +/- 3%, P = NS). However, with 1 mU/ml of VP, a significant decrease in Jv was evident in LiCl-treated (-30 +/- 10%) versus control sacs (+6 +/- 8%; P less than 0.02). At all VP concentrations tested, a significant decrease in SCC and PD was observed between the first stimulation without LiCl and the second stimulation with LiCl. Both osmotic (Pf) and diffusional water permeability (Pd) were increased significantly with 11 mM LiCl only, while neither basal nor VP-stimulated urea permeability (Pu) was affected. Morphological changes paralleled the physiological alterations induced by LiCl. These data demonstrate that LiCl interferes with the osmotic response of the toad bladder to low concentrations of VP, and increases both Pf and Pd while leaving Pu unaffected. These findings coupled with the cell swelling and intracellular vacuolization suggest the presence of a defect in transepithelial water movement somewhere beyond the apical membrane of the granular cell exposed to LiCl.

Effects of endogenous antidiuretic hormone (ADH) on macrophage phagocytosis

Although several studies have indicated that antidiuretic hormone (ADH) enhances the phagocytic function of the reticuloendothelial system (RES) in shock syndromes, it remains unknown what influence ADH exerts upon the individual phagocytic components of this system. The present investigation was designed to evaluate the effects of endogenous ADH on the phagocytic activity of peritoneal macrophage cells. As a phagocytic stimuli, fluorescent methacrylate microbeads were injected intraperitoneally into Brattleboro (ADH deficient) and normal Long Evans rats in the presence and absence of exogenous ADH. Peritoneal cells were harvested 19-22 hr after the administration of the microbeads and the percent phagocytosis was determined in macrophage cells using a fluorescence-activated cell sorter (FACS II). Our results indicate that the percentage of peritoneal macrophages ingesting the fluorescent methacrylate microbeads was significantly reduced in the absence of ADH (Brattleboro rats: 5.4 +/- 0.6% versus Long Evans rats: 16.8 +/- 2.3%; p less than 0.001). In addition, our data demonstrate that exogenous administration of ADH significantly enhanced macrophage phagocytosis in Brattleboro (14.7 +/- 2.2%) and normal Long Evans (49.6 +/- 4.5%) rats. These data suggest, for the first time, that endogenous ADH might play a modulatory role in the phagocytic activity of a specific component of the RES, namely, the macrophage cell.