Digital Commons Network^™

Micrornas: Tiny Regulators With Great Potential, Victor Ambros

Victor R. Ambros

Animal genomes contain an abundance of small genes that produce regulatory RNAs of about 22 nucleotides in length. These microRNAs are diverse in sequence and expression patterns, and are evolutionarily widespread, suggesting that they may participate in a wide range of genetic regulatory pathways.

Growth And Metabolism Of Larval Zebrafish: Effects Of Swim Training, Brian P. Bagatto, B. Pelster, W. W. Burggren

Brian P. Bagatto

Larval zebrafish (Danio rerio) of three different age classes ('yolk-sac' larvae, 96 h; 'swim-up' larvae, 9 days old; and 'free-swimming' larvae, 21 days old) were trained for 2, 6 and 11 days, respectively, to swim at 0 body lengths per second (BL s(-1)), 2 BL s(-1) and 5 BL s(-1). Survival was significantly diminished in larvae trained at 5 BL s(-1) compared to controls (0 BL s(-1)). Although training produced no significant differences in mass and length, the youngest larvae absorbed their yolk at a faster rate during training. Routine oxygen consumption (M(O2r)) and mass-specific routine oxygen consumption (MO(2r,m)) were …

Antigen Polymorphism In Borrelia Hermsii, A Clonal Pathogenic Bacterium, Stephen M. Rich, Stanley A. Sawyer, Alan G. Barbour

Stephen M. Rich

The relapsing fever spirochete, Borrelia hermsii, escapes immune selection by alternating expression of surface lipoprotein alleles. The switch results from a duplicative transposition of one of several surface lipoprotein-encoding nucleotide sequences into the singular expression site. These nucleotide sequences constitute a large gene family whose diversity originated, in some cases, before the major divergences of Borrelia species. We have examined the B. hermsii vsp subfamily of alleles, which are carried on linear plasmids within each cell and maintained in several diverse copies as an antigenic archive. Each encodes a distinct serotype-specific protein. We sequenced more than 90% of the alleles …

Protective Killed Leptospira Borgpetersenii Vaccine Induces Potent Th1 Immunity Comprising Responses By Cd4 And Gammadelta T Lymphocytes, B. M. Naiman, D. Alt, C. A. Bolin, R. Zuerner, Cynthia Baldwin

Cynthia Baldwin

Leptospira borgpetersenii serovar hardjo is the most common cause of bovine leptospirosis and also causes zoonotic infections of humans. A protective killed vaccine against serovar hardjo was shown to induce strong antigen-specific proliferative responses by peripheral blood mononuclear cells (PBMC) from vaccinated cattle by 2 months after the first dose of vaccine. This response was absent from nonvaccinated control cattle. The mean response peaked by 2 months after completion of the two-dose vaccination regimen, and substantial proliferation was measured in in vitro cultures throughout the 7 months of the study period. Variations in magnitude of the response occurred among the …

Effect Of Combination Therapy Including Protease Inhibitors On Mortality Among Children And Adolescents With Hiv-1

Joseph Cervia

No abstract provided.

Blood-Squirting Variability In Horned Lizards (Phrynosoma), Wade Sherbrooke, George Middendorf, C. Guyer

George Middendorf

Use Of Molecular Probes To Assess Geographic Distribution Of Pfiesteria Species, Torstein Tengs

Dr. Torstein Tengs

We have developed multiple polymerase chain reaction (PCR)-based methods for the detection of Pfiesteria sp. in cultures and environmental samples. More than 2,100 water and sediment samples from estuarine sites of the U.S. Atlantic and gulf coasts were assayed for the presence of Pfiesteria piscicida Steidinger & Burkholder and Pfiesteria shumwayae Glasgow & Burkholder by PCR probing of extracted DNA. Positive results were found in about 3% of samples derived from routine monitoring of coastal waters and about 8% of sediments. The geographic range of both species was the same, ranging from New York to Texas. Pfiesteria spp. are likely …

Classification And Identification Of Pfiesteria And Pfiesteria-Like Species, Torstein Tengs

Dr. Torstein Tengs

Dinoflagellates can be classified both botanically and zoologically; however, they are typically put in the botanical division Pyrrhophyta. As a group they appear most related to the protistan ciliates and apicomplexans at the ultrastructure level. Within the Pyrrhophyta are both unarmored and armored forms of the dominant, motile flagellated stage. Unarmored dinoflagellates do not have thecal or wall plates arranged in specific series, whereas armored species have plates that vary in thickness but are specific in number and arrangement. In armored dinoflagellates, the plate pattern and tabulation is a diagnostic character at the family, subfamily, and even genus levels. In …

Quarrington’S Hockey Schtick: A Literary Analysis, Don Morrow

Donald Morrow

No abstract provided.

Cloning Of Canine Γ-Tubulin (Tubg1) Cdna And Mapping To Cfa9, Duska J. Sidjanin, F Xue, J Mcelwee, Jennifer L. Johnson, C Holmgren, Cathryn S. Mellersh, Elaine A. Ostrander, Gregory M. Acland, Gustavo D. Aguirre

Gustavo D. Aguirre, VMD, PhD

No abstract provided.

A Conserved Ubiquitin Ligase Of The Nuclear Envelope/Endoplasmic Reticulum That Functions In Both Er-Associated And Mat A2 Repressor Degradation, Rob Swanson

Rob Swanson

Substrate discrimination in the ubiquitin–proteasome system is believed to be dictated by specific combinations of ubiquitin–protein ligases (E3s) and ubiquitin-conjugating enzymes (E2s). Here we identify Doa10/Ssm4 as a yeast E3 that is embedded in the endoplasmic reticulum (ER)/nuclear envelope yet can target the soluble transcription factor Mat2. Doa10 contains an unusual RING finger, which has ubiquitin-ligase activity in vitro and is essential in vivo for degradation of 2 via its Deg1 degradation signal. Doa10 functions with two E2s, Ubc6 and Ubc7, to ubiquitinate Deg1-bearing substrates, and it is also required for the degradation of at least one ER membrane protein. …

Influential Parameters Of Job Stress - A Regression Analysis Of Women Scientists In Indian Agricultural Research System, Aneeja Guttikonda

aneeja guttikonda

No abstract provided.

Development. Dicing Up Rnas, Victor Ambros

Victor R. Ambros

Comment on: A cellular function for the RNA-interference enzyme Dicer in the maturation of the let-7 small temporal RNA. [Science. 2001]

A Genetic And Molecular Analysis Of Spermiogenesis Initiation In Caenorhabditis Elegans, Paul J. Muhlrad

Paul J Muhlrad

How do cells acquire and regulate their specialized forms and functions? This is the fundamental question underlying the experiments described in this dissertation. To examine this question, I have peered deeply into an exquisitely specialized cell from a genetically tractable organism: the spermatozoon of the nematode, Caenorhabditis elegans. C. elegans sperm orchestrate a fantastic morphogenetic transformation under severe constraints of time and cellular resources. In response to an external signal, spermatids reorganize their membranes and cytoskeleton to form crawling spermatozoa.This maturation, termed spermiogenesis, ensues without any new gene expression. To better understand this signaling pathway, I isolated suppressors of a …

Influence Of Fermentation And Cowpea Steaming On Some Quality Characteristics Of Maize-Cowpea Blends, Samuel Sefa-Dedeh, Yvonne Kluvitse, Emmanuel Ohene Afoakwa

Professor Emmanuel Ohene Afoakwa

Fermentation and cowpea steaming can be used to improve the protein quality and quantity of fermented maize dough. In the production of maize-cowpea blends, it is important that the quality characteristics are evaluated to determine their functionality in the products. A 5x4x2x2 factorial experiment with cowpea level, fermentation time, cowpea steaming time and fermentation method as the variable was performed. The cowpeas were dehulled, steamed, dried at 65EC for 24 hours and milled into flours. Maize was soaked in water (18 hours), drained and milled into flour. The maize-cowpea blends were made into a 50% moisture dough, fermented for the …

Reductive Presipitation Of Gold By Dissimilatory Fe(Iii)-Reducing Bacteria And Archaea, Kazem Kashefi, Jason M. Tor, Kelly P. Nevin, Derek Lovley

Kelly Nevin

Studies with a diversity of hyperthermophilic and mesophilic dissimilatory Fe(III)-reducing Bacteria andArchaea demonstrated that some of these organisms are capable of precipitating gold by reducing Au(III) to Au(0) with hydrogen as the electron donor. These studies suggest that models for the formation of gold deposits in both hydrothermal and cooler environments should consider the possibility that dissimilatory metal-reducing microorganisms can reductively precipitate gold from solution.

Liquid Dairy Waste Transport And Land Application Cost Comparisons Considering Herd Size, Transport Distance, And Nitrogen Versus Phosphorus Application Rates, Robert T. Burns, A. S. Daugherty, T. L. Cross, D. Raj Raman, G. F. Grandle

D. Raj Raman

This study provides cost comparisons for the transport and application of dairy waste slurries based on both phosphorus and nitrogen application rates. Estimated cost comparisons are made for several commonly used systems for dairy waste transport and application. Five dairy sizes ranging from 50 to 2,000 cows using 13 transport and application systems were evaluated. For each dairy size, the costs associated with the transport and application system combinations were determined for transport distances of 0.5, 1.5, and 4.5 miles for both nitrogen and phosphorus-based application rates. Total annual system cost, cost per acre, cost per cow, and manure value …

Incidence Of Escherichia Coli O157:H7, Listeria Monocytogenes , And Salmonella Species On A Tennessee Dairy Farm, T. L. Ervin, R. E. Yoder, F. A. Draughon, Robert T. Burns, D. Raj Raman

D. Raj Raman

In response to public awareness of foodborne pathogens due to recent outbreaks of illness, a study was conducted on the incidence of Escherichia coli O157:H7, Listeria monocytogenes , and Salmonella species on a dairy farm in middle Tennessee. Sampling locations included water samples from up- and down-stream in a creek running through the farm, free stall bedding, silage, separator liquids, separator solids, pumped liquid from a holding pond, feed, and bulk tank milk. Three samples were taken monthly at each location for 12 months. These samples were tested to determine the incidence of pathogens on the dairy farm and to …

Invasion Terminology: Should Ecologists Define Their Terms Differently Than Others? No, Not If We Want To Be Of Any Help!, Mark Davis, K Thompson

Mark Davis

No abstract provided.

Β-Lactoglobulin Molten Globule Induced By High Pressure, Jian Yang, A. Keith Dunker, Joseph R. Powers, Stephanie Clark, Barry G. Swanson

Stephanie Clark

Beta-lactoglobulin (beta-LG) was treated with high hydrostatic pressure (HHP) at 600 MPa and 50 degrees C for selected times as long as 64 min. The intrinsic tryptophan fluorescence of beta-LG indicated that HHP treatment conditions induced a conformational change. HHP treatment conditions also promote a 3-fold increase in the extrinsic fluorescence of 1-anilinonaphthalene-8-sulfonate and a 2.6-fold decrease for cis-paraneric acid, suggesting an increase in accessible aromatic hydrophobicity and a decrease in aliphatic hydrophobicity. Far-ultraviolet circular dichroism (CD) spectra reveal that the secondary structure of beta-LG converts from native beta-sheets to non-native alpha-helices following HHP treatment, whereas near-ultraviolet CD spectra reveal …

Book Review Of "Ecology And Conservation Of Grassland Birds Of The Western Hemisphere", Eric K. Bollinger

Eric K. Bollinger

This book review appeared in The Auk, Volume 118 No. 3 (July 2001).

Characterization Of Partially Transesterified Poly(Β-Hydroxyalkanoate)S By Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry, Broderick Eribo

Broderick Eribo

G Protein Regulation Of Ion Channels And Abscisic Acid Signaling In Arabidopsis Guard Cells, Hemayet Ullah, Xi-Qing Wang, Alan M. Jones, Sarah M. Assmann

Hemayet Ullah

Isolation And Characterization Of A Soluble Nadph-Dependant Fe(Iii) Reductase From Geobacter Sulfurreducens, Franz Kaufmann, Derek Lovley

Derek Lovley

NADPH is an intermediate in the oxidation of organic compounds coupled to Fe(III) reduction in Geobacter species, but Fe(III) reduction with NADPH as the electron donor has not been studied in these organisms. Crude extracts of Geobacter sulfurreducens catalyzed the NADPH-dependent reduction of Fe(III)-nitrilotriacetic acid (NTA). The responsible enzyme, which was recovered in the soluble protein fraction, was purified to apparent homogeneity in a four-step procedure. Its specific activity for Fe(III) reduction was 65 micromol. min(-1). mg(-1). The soluble Fe(III) reductase was specific for NADPH and did not utilize NADH as an electron donor. Although the enzyme reduced several forms …

Visualizing Rhizosphere Chemistry Of Legumes With Mid-Infrared Synchrotron Radiation, Ted K. Raab, Michael C. Martin

Ted K. Raab

A bright synchrotron light source operated by the Lawrence Berkeley National Laboratory served as an external source for infrared (IR) microscopy of plant root microcosms. Mid-IR light from synchrotrons is 2-3 orders of magnitude brighter than conventional sources, providing contrast based on the chemical information in the reflected signal at a spatial resolution near the diffraction-limit of 3-10 microns. In an experiment using plant root microcosms fitted with zinc selenide IR-transmissive windows (50 mm x 20 mm x 1 mm), we describe chemical differences and similarities within the root zone of mung bean (Vigna radiata L.), grown with or without …

Method For Determining Oxidation Of Vegetable Oils By Near-Infrared Spectroscopy, Gulgun (Yildiz) Tiryaki

Dr. Gülgün YILDIZ TIRYAKI

No abstract provided.

Cobra Encodes A Putative Gpi-Anchored Protein, Which Is Polarly Localized And Necessary For Oriented Cell Expansion In Arabidopsis, Tobias Baskin, G. Schindelman, A. Morikami, J. Jung, N.C. Carpita, P. Derbyshire, M.C. Mccann, P.N. Benfey

Tobias Baskin

To control organ shape, plant cells expand differentially. The organization of the cellulose microfibrils in the cell wall is a key determinant of differential expansion. Mutations in the COBRA (COB) gene of Arabidopsis, known to affect the orientation of cell expansion in the root, are reported here to reduce the amount of crystalline cellulose in cell walls in the root growth zone. The COB gene, identified by map-based cloning, contains a sequence motif found in proteins that are anchored to the extracellular surface of the plasma membrane through a glycosylphosphatidylinositol (GPI) linkage. In animal cells, this lipid linkage is known …

One Hundred - Not Out: Henry Roxborough’S Shaping Of Canadian Sport History, Don Morrow

Donald Morrow

No abstract provided.

Reversible Calcium-Regulated Stopcocks In Legume Sieve Tubes, Michael Knoblauch, Winfried Peters, Katrin Ehlers, Aart Van Bel

Winfried S. Peters

Development Of A Genetic System For Geobacter Sulfurreducens, Maddalena V. Coppi, Ching Leang, Steven J. Sandler, Derek Lovley

Derek Lovley

Members of the genus Geobacter are the dominant metal-reducing microorganisms in a variety of anaerobic subsurface environments and have been shown to be involved in the bioremediation of both organic and metal contaminants. To facilitate the study of the physiology of these organisms, a genetic system was developed forGeobacter sulfurreducens. The antibiotic sensitivity of this organism was characterized, and optimal conditions for plating it at high efficiency were established. A protocol for the introduction of foreign DNA into G. sulfurreducens by electroporation was also developed. Two classes of broad-host-range vectors, IncQ and pBBR1, were found to be capable of replication …