Testing extraction and storage parameters for a fecal hormone method

Four experiments were conducted to test different aspects of a “field-friendly” fecal hormone extraction method that utilizes methanol extraction in the field followed by storage on C18 solid-phase extraction cartridges. Fecal samples were collected from geladas ( Theropithecus gelada ) housed at the Bronx Zoo, and the experiments were conducted in a laboratory setting to ensure maximum control. The experiments were designed to either simulate the conditions to which fecal samples are subjected during fieldwork or improve on an existing protocol. The experiments tested the relationship between fecal hormone metabolite preservation/recovery and: (1) the amount of time a sample is stored at ambient temperature; (2) the number of freeze/thaw cycles a sample undergoes; (3) the effectiveness of different extraction solutions; and (4) the effectiveness of different cartridge washes. For each experiment, samples were assayed by radioimmunoassay for fecal glucocorticoid (GC) and testosterone (T) metabolites. Results for each of the experiments were as follows. First, storage at ambient temperature did not affect hormone levels until 4 weeks of storage, with significant increases for both GC and T metabolites at 4 weeks. Second, hormone levels significantly decreased in samples after two freeze/thaw cycles for GCs and six freeze/thaws cycles for T. Third, for both GCs and T, hormone extraction using various methanol solutions was significantly higher than using 100% ethanol. Finally, using a 20% methanol solution to wash cartridges significantly increased GC levels but had no effect on T levels. These results suggest that, when utilizing C18 cartridges for fecal steroid storage, researchers should consider several methodological options to optimize hormone preservation and recovery from fecal samples. Am. J. Primatol. 72:934–941, 2010. © 2010 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78062/1/20859_ftp.pd

Summary Report for the Initiation of Compact Development for Particles with 425-micron Kernels

The purpose of this research was the initiation of overcoating TRISO particles with 425 {micro}m kernels. In the AGR-1 task, the overcoating process was optimized for particles with an outer diameter (OD) of 780 {micro}m and a 350 {micro}m kernel. Therefore it needed to be determined how well the overcoating process used to fabricate AGR-1 compacts would perform on particles with an 855 {micro}m OD and a 425 {micro}m kernel. The matrix properties and overcoating procedures were altered from the AGR-1 processes in order to attempt to optimize the overcoating of TRISO particles with 425 {micro}m kernels. This report summarizes the changes that were made to the matrix and the overcoating process in order to achieve successful overcoating of the larger particles

The Reproductive Trajectories of Bachelor Geladas.

Sexual selection strongly influences patterns of male behavior. Fertilizations cannot be shared, therefore male-male relationships tend to be agonistic rather than affiliative. Despite this fact, males in many species form all-male groups that vary in composition and stability. All-male groups have been observed in many mammalian taxa including cetaceans, ungulates, and primates. Because few studies have examined these groups directly, we know little of how they form, the social relationships between the males that comprise them, or if such relationships influence future reproductive success. Geladas (Theropithecus gelada) are an Old World monkey species where males disperse from their natal units and join all-male groups prior to acquiring reproductive access to females. In this study, I examine the behavioral, hormonal, and genetic factors that shape the reproductive trajectories of bachelor geladas living in all-male groups. This study has four major components. First, I address how gelada all-male groups form. I demonstrate that relatedness influences all-male group formation, although only few pairs of males were considered close kin. Second, I ask how bachelors interact within their groups. I show that bachelors form stratified social bonds within their all-male groups. These bonds were strongest between males that were closely related and similar in age. Third, I attempt to answer how bachelors become dominant “leader” males. Males that eventually became dominant had higher testosterone levels during the bachelor period. I draw on extended field-based observations of wild geladas (2006-2011) as well as hormonal and genetic data to answer my study questions. These findings represent the first study of gelada all-male groups and one of the few studies on such groups in related species.PhDAnthropologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/102358/1/pappano_1.pd

Antibacterial Efficacy of Dihydroxylated Chalcones in Binary and Ternary Combinations with Nalidixic Acid and Nalidix Acid-Rutin Against Escherichia coli ATCC 25 922

In order to determine the existence of synergism, the bacteriostatic action of flavonoids against Escherichia coli ATCC 25 922 between dihydroxylated chalcones and a clinically interesting conventional antibiotic, binary combinations of 2′,3-dihydroxychalcone, 2′,4-dihydroxychalcone and 2′,4′-dihydroxychalcone with nalidixic acid and its ternary combinations with rutin (inactive flavonoid) were assayed against this Gram negative bacterium. Using a kinetic-turbidimetric method, growth kinetics were monitored in broths containing variable amounts of dihydroxychalcone alone, combinations of dihydroxychalcone variable concentration-nalidixic acid constant concentration and dihydroxychalcone variable concentration-nalidixic acid constant concentration-rutin constant concentration, respectively. The minimum inhibitory concentrations of dihydroxychalcones alone and its binary and ternary combinations were evaluated. All chalcones, and their binary and ternary combinations showed antibacterial activity, being rutin an excellent synergizing for the dihydroxychalcone-nalidixic acid binary combination against E. coli ATCC 25 922. Thus, this synergistic effect is an important way that could lead to the development of new combination antibiotics against infections caused by E. coli.Fil: Talia, Juan Manuel. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Tonn, Carlos Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: Debattista, Nora Beatriz. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; ArgentinaFil: Pappano, Nora Beatriz. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentin

Research & Action Report, Fall/Winter 2007

In this issue: Women and Children: The Human Rights Relationship Adolescent Literacy and Achievement: Widening the Path to Success Is Literacy Enough? Squeeze Play: Why Title IX Is Not Enoughhttps://repository.wellesley.edu/researchandactionreport/1011/thumbnail.jp

Biosynthesis and enzymology of the Caenorhabditis elegans cuticle: identification and characterization of a novel serine protease inhibitor.

The nematode Caenorhabditis elegans represents an excellent model in which to examine nematode gene expression and function. A completed genome, straightforward transgenesis, available mutants and practical genome-wide RNAi approaches provide an invaluable toolkit in the characterization of nematode genes. We have performed a targeted RNAi screen in an attempt to identify components of the cuticle collagen biosynthetic pathway. Collagen biosynthesis and cuticle assembly are multi-step processes that involve numerous key enzymes involved in post-translational modification, trimer folding, procollagen processing and subsequent cross-linking stages. Many of these steps, the modifications and the enzymes are unique to nematodes and may represent attractive targets for the control of parasitic nematodes. A novel serine protease inhibitor was uncovered during our targeted screen, which is involved in collagen maturation, proper cuticle assembly and the moulting process. We have confirmed a link between this inhibitor and the previously uncharacterized bli-5 locus in C. elegans. The mutant phenotype, spatial expression pattern and the over-expression phenotype of the BLI-5 protease inhibitor and their relevance to collagen biosynthesis are discussed