Tethering: fragment-based drug discovery.

The genomics revolution has provided a deluge of new targets for drug discovery. To facilitate the drug discovery process, many researchers are turning to fragment-based approaches to find lead molecules more efficiently. One such method, Tethering1, allows for the identification of small-molecule fragments that bind to specific regions of a protein target.

Mechanistic diversity of cytokine receptor signaling across cell membranes.

Circulating cytokines bind to specific receptors on the cell outer surface to evoke responses inside the cell. Binding of cytokines alters the association between receptor molecules that often cross the membrane only once in a single alpha-helical segment. As a consequence, association of protein domains on the inside of the membrane are also altered.

Mental health impact of 9/11 Pentagon attack: validation of a rapid assessment tool.

Background: Following the tragic events of 9/11/2001, the Pentagon Post Disaster Health Assessment (PPDHA) survey was created to identify healthcare needs and concerns among Pentagon personnel and to assure that appropriate care and information was provided. The PPDHA was fielded from October 15, 2001, to January 15, 2002. Fundamental in this assessment was the evaluation of the mental health impact as a result of the attack.

Potent small-molecule binding to a dynamic hot spot on IL-2.

The complexes between IL-2 and two similar small molecules, one a lead compound and the other a potent, affinity-optimized compound, were determined by X-ray crystallography. The lead compound (IC50 = 6 muM) bound to a hot spot on IL-2 in a groove that is not apparent in either the unliganded protein or a complex between IL-2 and a weakly bound drug fragment. The affinity-optimized compound (IC50 = 0.

Endonuclease G is required for early embryogenesis and normal apoptosis in mice.

Endonuclease G (EndoG) is a nuclear-encoded mitochondrial protein reported to be important for both nuclear DNA fragmentation during apoptosis and mitochondrial DNA replication. To evaluate the in vivo function of EndoG, we have investigated the effects of EndoG deficiency in cells and mice. We found that EndoG homozygous mutant embryos die between embryonic days 2.

Global expression analysis of gene regulatory pathways during endocrine pancreatic development.

To define genetic pathways that regulate development of the endocrine pancreas, we generated transcriptional profiles of enriched cells isolated from four biologically significant stages of endocrine pancreas development: endoderm before pancreas specification, early pancreatic progenitor cells, endocrine progenitor cells and adult islets of Langerhans. These analyses implicate new signaling pathways in endocrine pancreas development, and identified sets of known and novel genes that are temporally regulated, as well as genes that spatially define developing endocrine cells from their neighbors. The differential expression of several genes from each time point was verified by RT-PCR and in situ hybridization.

Monomers and oligomers of the M2 muscarinic cholinergic receptor purified from Sf9 cells.

G protein-coupled receptors are known to form oligomers. To probe the nature of such aggregates, as well as the role and prevalence of monomers, epitope-tagged forms of the M(2) muscarinic receptor have been isolated as oligomers and monomers from Sf9 cells. Membranes from cells coexpressing the c-Myc- and FLAG-tagged receptor were solubilized in digitonin-cholate, and the receptor was purified by successive passage through DEAE-Sepharose, the affinity resin 3-(2'-aminobenzhydryloxy)tropane (ABT)-Sepharose, and hydroxyapatite.

Long-term stewardship of the environmental legacy at restored sites within the Department of Energy nuclear weapons complex.

It is readily apparent, as the Department of Energy Office of Environmental Management proceeds in remediating its vast network of contaminated nuclear weapons facilities, that final cleanup at many facilities will not be performed to a level allowing unrestricted use of the facility. Instead, these facilities must rely on engineering, administrative, and institutional controls to ensure the level of cleanup performed at the site remains adequately protective of public health and the environment. In order for these controls to remain effective, however, a plan for long-term stewardship of these sites must be developed that is approved by the U.

Direct activation of the apoptosis machinery as a mechanism to target cancer cells.

Apoptosis plays a pivotal role in the cytotoxic activity of most chemotherapeutic drugs, and defects in this pathway provide a basis for drug resistance in many cancers. Thus the ability to restore apoptosis by using small molecules could have important therapeutic implications. Using a cell-free assay to simultaneously target multiple components of the apoptosis pathway, we identified a class of compounds that activate caspases in a cytochrome c-dependent manner and induce apoptosis in whole cells.

Genes expressed in the developing endocrine pancreas and their importance for stem cell and diabetes research.

The genes that regulate endocrine pancreas development, maintain adult endocrine cells, and stimulate progenitor/stem cells during regeneration remain largely unstudied. There is ample evidence that many of the genes involved in endocrine pancreas development also function in the homeostasis of the adult islet. In light of the potential benefits to diabetic research, it is surprising that there is little information about the genes expressed throughout the ontogeny of the endocrine pancreas.

Development and application of a polymerase chain reaction assay for the detection and enumeration of bile acid 7alpha-dehydroxylating bacteria in human feces.

Background: Secondary bile acids are synthesized in the human colon from the bacterial 7alpha-dehydroxylation of primary bile acids. Increased levels of secondary bile acids have been correlated with an increased risk of colon cancer and cholesterol gallstone disease. Based on 16s rDNA sequence analysis, stock cultures of bacterial strains with bile acid 7alpha-dehydroxylation all belong to the genus Clostridium.

Binding of small molecules to an adaptive protein-protein interface.

Understanding binding properties at protein-protein interfaces has been limited to structural and mutational analyses of natural binding partners or small peptides identified by phage display. Here, we present a high-resolution analysis of a nonpeptidyl small molecule, previously discovered by medicinal chemistry [Tilley, J. W.

Estimating seat belt effectiveness using matched-pair cohort methods.

Using US data for 1986-1998 fatal crashes, we employed matched-pair analysis methods to estimate that the relative risk of death among belted compared with unbelted occupants was 0.39 (95% confidence interval (CI) 0.37-0.

The U.S. Army Center for Health Promotion and Preventive Medicine response to the Pentagon attack: a multipronged prevention-based approach.

Personnel of the U.S. Army Center for Health Promotion and Preventive Medicine responded to the September 11, 2001 terrorist attack on the Pentagon with in a multipronged approach that encompassed the areas of environmental science, behavioral health, occupational and preventive medicine, risk communication, epidemiology, and medical surveillance.

Effects of N-ethylmaleimide on conformational equilibria in purified cardiac muscarinic receptors.

Muscarinic receptors purified from porcine atria and devoid of G protein underwent a 9-27-fold decrease in their apparent affinity for the antagonists quinuclidinyl benzilate, N-methylscopolamine, and scopolamine when treated with the thiol-selective reagent N-ethylmaleimide. Their apparent affinity for the agonists carbachol and oxotremorine-M was unchanged. Conversely, the rate of alkylation by N-ethylmaleimide, as monitored by the binding of [(3)H]quinuclidinyl benzilate, was decreased by antagonists while agonists were without effect.

Biomechanics of growth and development in the healthy human infant: a pilot study.

Detailed measurements were acquired from 168 healthy subjects who were brought to the West Virginia School of Osteopathic Medicine's Robert C. Byrd Clinic in Lewisburg, WVa, during 1998 and 1999 by their parents for routine well-baby visits. Measurements of body-segment length, diameter, circumference, and skinfold thickness were taken at several segment locations.

Cooperativity and oligomeric status of cardiac muscarinic cholinergic receptors.

Muscarinic cholinergic receptors can appear to be more numerous when labeled by [(3)H]quinuclidinylbenzilate (QNB) than by N-[(3)H]methylscopolamine (NMS). The nature of the implied heterogeneity has been studied with M(2) receptors in detergent-solubilized extracts of porcine atria. The relative capacity for [(3)H]NMS and [(3)H]QNB was about 1 in digitonin-cholate, 0.

The Recruit assessment Program: a program to collect comprehensive baseline health data from U.S. military personnel.

Pilot testing has begun on the Recruit Assessment Program (RAP). The RAP is a proposed Department of Defense (DoD) program for the routine collection of baseline demographic, medical, psychosocial, occupational, and health risk factor data from all U.S.

Measurement of body segment mass, center of gravity, and determination of moments of inertia by double pendulum in Lemur fulvus.

The collection of data on physical parameters of body segments is a preliminary critical step in studying the biomechanics of locomotion. Little data on nonhuman body segment parameters has been published. The lack of standardization of techniques for data collection and presentation has made the comparative use of these data difficult and at times impossible.

Positional and activity behavior in a captive slow loris: A quantitative assessment.

This study examines the positional and activity behavior of a captive slow loris, Nycticebus coucang. The male individual was housed in a primate facility providing a seminatural environment and was subjected to a series of videotape recordings from which 1,878 point observations were taken. The enclosure was designed to allow maximum flexibility of substrate use.