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2012

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Full-Text Articles in Life Sciences

Nursing Females Are More Prone To Heat Stress: Demography Matters When Managing Flying-Foxes For Climate Change, Stephanie T. Snoyman, Jasmina Munich, Culum Brown Dec 2012

Nursing Females Are More Prone To Heat Stress: Demography Matters When Managing Flying-Foxes For Climate Change, Stephanie T. Snoyman, Jasmina Munich, Culum Brown

Ecological Impacts of Climate Change Collection

Determining the underlying mechanisms responsible for species-specific responses to climate change is important from a species management perspective. The grey-headed flying-fox, Pteropus poliocephalus, is listed as vulnerable but it also a significant pest species for orchardists and thereby presents an interesting management conundrum. Over the last century, the abundance of the grey-headed flying-fox, P. poliocephalus, in Australia has decreased due to a variety of threatening processes but has increased in abundance in urban areas. These flying-foxes are highly susceptible to extreme heat events which are predicted to increase in the future under climate change scenarios. Exceptionally hot days result in …


The Lyme Disease Spirochete In Tick Species Collected From Warren County, Kentucky, Cheryl C. Onwu Dec 2012

The Lyme Disease Spirochete In Tick Species Collected From Warren County, Kentucky, Cheryl C. Onwu

Mahurin Honors College Capstone Experience/Thesis Projects

The overall goal of this present study was to determine the prevalence of the Lyme disease spirochete, Borrelia burgdorferi, in south central Kentucky. A survey of ticks collected from a single location in Warren County, Kentucky was conducted between the months of April and June, 2010. A total of 293 ticks were collected. Three species were identified: 264 (91.7 %) of the ticks were Amblyoma americanum, 18 (6.6%) were Dermacentor variabilis, and 1 (0.35%) was Ixodes scapularis. The ten remaining ticks were immature nymphs and could not be identified. After identifying the species and sex of …


What's That Hooting Sound? A Survey On Novel Sound Producing Mechanisms In Chameleons, Keyana Boka Dec 2012

What's That Hooting Sound? A Survey On Novel Sound Producing Mechanisms In Chameleons, Keyana Boka

Mahurin Honors College Capstone Experience/Thesis Projects

This research project seeks to study how chameleons generate low frequency vibrations, some audible and some not. The mechanism responsible for this 'hoot' is unknown. A modified tracheal appendage we termed “the resonator” has been hypothesized as the potential source of this sound. An anatomical survey was conducted on various chameleon species including, Chameleo melleri (Meller), Chamaeleo pardalis (Ambanja, Nosy Be, Panther, Sambava), Furcifer rhinoceratus, Chamaeleo dilepis (Flapneck), Chamaeleo rudis (Side-striped), Chamaeleo calyptratus (Veiled), Chamaeleo jacksonii (Jackson’s), Chamaeleo quadricornicus (4-horned), Chamaeleo quilensis (Flapneck), Chamaeleo senegalensis (Senegal), Chamaeleo jacksonii xantholophus (giant Jackson’s), and Rhampholean brevicaudatus (Pygmy). Each chameleon was dissected …


Assimilating Altimetric Data Into A South China Sea Model, Chau-Ron Wu, Ping-Tung Shaw, Shenn-Yu Chao Dec 2012

Assimilating Altimetric Data Into A South China Sea Model, Chau-Ron Wu, Ping-Tung Shaw, Shenn-Yu Chao

Faculty Publications

Sea surface heights from the TOPEX/Poseidon altimeter are assimilated into a three-dimensional primitive equation model to derive the circulation in the South China Sea. With data assimilation the model resolves not only the basinwide circulation but also a dipole off Vietnam and a low/high feature near the Luzon Strait. Mesoscale features are missing in the simulation without data assimilation because of poor resolution in the wind field and inadequate knowledge of the transport through the Luzon Strait. Compared to the case without data assimilation, data assimilation reduces the root mean square error between the simulated and observed sea surface heights …


Essays On The U.S Biofuel Policies: Welfare Impacts And The Potential For Reduction Of Ghg Emission, Kassu Wamisho Hossiso Dec 2012

Essays On The U.S Biofuel Policies: Welfare Impacts And The Potential For Reduction Of Ghg Emission, Kassu Wamisho Hossiso

Department of Agricultural Economics: Dissertations, Theses, and Student Research

This dissertation study investigates the impact of the US biofuel policies related to greenhouse gas (GHG) emission regulation, tax credit and renewable fuel standard (RFS2) mandate over production and consumption of ethanol as well as technical and environmental performance of corn ethanol plants. The study develops analytical models and provides quantitative estimation of the impact of various biofuel policies in each of the three chapters.

Chapter 1 of this dissertation examines the tradeoff between achieving the environmental goal of minimizing life cycle GHG emissions and minimizing production costs in recently built dry-grind corn ethanol plants. The results indicate that the …


Depth-Variable Settlement Patterns And Predation Influence On Newly Settled Reef Fishes (Haemulon Spp., Haemulidae), Lance K.B. Jordan, Kenyon C. Lindeman, Richard E. Spieler Dec 2012

Depth-Variable Settlement Patterns And Predation Influence On Newly Settled Reef Fishes (Haemulon Spp., Haemulidae), Lance K.B. Jordan, Kenyon C. Lindeman, Richard E. Spieler

Ocean Engineering and Marine Sciences Faculty Publications

During early demersal ontogeny, many marine fishes display complex habitat-use patterns. Grunts of the speciose genus Haemulon are among the most abundant fishes on western North Atlantic coral reefs, with most species settling to shallow habitats (≤12 m). To gain understanding into cross-shelf distributional patterns exhibited by newly settled stages of grunts (<2 cm total length), we examined: 1) depth-specific distributions of congeners at settlement among sites at 8 m, 12 m, and 21 m, and 2) depth-variable predation pressure on newly settled individuals (species pooled). Of the six species identified from collections of newly settled specimens (n = 2125), Haemulon aurolineatum (tomtate), H. flavolineatum (French grunt), and H. striatum (striped grunt) comprised 98% of the total abundance; with the first two species present at all sites. Prevalence of H. aurolineatum and H. flavolineatum decreased substantially from the 8-m site to the two deeper sites. In contrast, H. striatum was absent from the 8-m site and exhibited its highest frequency at the 21-m site. Comparison of newly settled grunt delta density for all species on caged (predator exclusion) and control artificial reefs at the shallowest site (8-m) revealed no difference, while the 12-m and 21-m sites exhibited significantly greater delta densities on the caged treatment. This result, along with significantly higher abundances of co-occurring piscivorous fishes at the deeper sites, indicated lower predation pressure at the 8-m site. This study suggests habitat-use patterns of newly settled stages of some coral reef fishes that undergo ontogenetic shifts are a function of depth-variable predation pressure while, for at least one deeper-water species, proximity to adult habitat appears to be an important factor affecting settlement distribution.


Depth-Variable Settlement Patterns And Predation Influence On Newly Settled Reef Fishes (Haemulon Spp., Haemulidae), Lance K. B. Jordan, Kenyon C. Lindeman, Richard E. Spieler Dec 2012

Depth-Variable Settlement Patterns And Predation Influence On Newly Settled Reef Fishes (Haemulon Spp., Haemulidae), Lance K. B. Jordan, Kenyon C. Lindeman, Richard E. Spieler

Marine & Environmental Sciences Faculty Articles

During early demersal ontogeny, many marine fishes display complex habitat-use patterns. Grunts of the speciose genus Haemulon are among the most abundant fishes on western North Atlantic coral reefs, with most species settling to shallow habitats (≤12 m). To gain understanding into cross-shelf distributional patterns exhibited by newly settled stages of grunts (<2 cm total length), we examined: 1) depth-specific distributions of congeners at settlement among sites at 8 m, 12 m, and 21 m, and 2) depth-variable predation pressure on newly settled individuals (species pooled). Of the six species identified from collections of newly settled specimens (n = 2125), Haemulon aurolineatum (tomtate), H. flavolineatum(French grunt), and H. striatum (striped grunt) comprised 98% of the total abundance; with the first two species present at all sites. Prevalence of H. aurolineatum and H. flavolineatumdecreased substantially from the 8-m site to the two deeper sites. In contrast, …


The Contribution Of The Lateral Line To 'Hearing' In Fish, Dennis M. Higgs, C. A. Radford Dec 2012

The Contribution Of The Lateral Line To 'Hearing' In Fish, Dennis M. Higgs, C. A. Radford

Biological Sciences Publications

In the underwater environment, sound propagates both as a pressure wave and as particle displacement, with particle displacement dominating close to the source (the nearfield). At the receptor level, both the fish ear and the neuromast hair cells act as displacement detectors and both are potentially stimulated by the particle motion component of sound sources, especially in the nearfield. A now common way to test ?hearing' in fish involves auditory evoked potentials (AEPs), with recordings made from electrodes implanted near the auditory brainstem. These AEP recordings are typically conducted in enclosed acoustic environments with the fish well within the nearfield, …


Rr13-02 Corn Grain Hybrid Tests In Tennessee 2012, Fred L. Allen, Richard D. Johnson, Robert C. Williams Jr., Angela Thompson Mcclure Dec 2012

Rr13-02 Corn Grain Hybrid Tests In Tennessee 2012, Fred L. Allen, Richard D. Johnson, Robert C. Williams Jr., Angela Thompson Mcclure

Field & Commercial Crops

No abstract provided.


Traversing Swanton Road, 10th Ed., James A. West Dec 2012

Traversing Swanton Road, 10th Ed., James A. West

Academic, Government & Associated Organizational Research Resources

Situated at the northwest end of Santa Cruz County and occupying circa 30 square miles of sharply contrasted terrain, the Scott Creek Watershed concentrates within its geomorphological boundaries, at least 10-12% of California's flora, both native and introduced. Paradoxically, the use/abuse that the watershed has sustained over the past 140+ years, has not necessarily diminished the biodiversity and perhaps parallels the naturally disruptive but biologically energizing processes (fire, flooding, landslides and erosion), which have also been historically documented for the area for +60 years. This is an early edition of an extensive document by James A. West. Please visit the …


Eating Patterns And Physical Activity Characteristics Among Urban And Rural Students In Saudi Arabia, Omar I. Abuzaid Dec 2012

Eating Patterns And Physical Activity Characteristics Among Urban And Rural Students In Saudi Arabia, Omar I. Abuzaid

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Human obesity has become a global phenomenon. The main goal of this study was to investigate the differences in food consumption and physical activity among high school age youth in two diverse geographical locations (urban and rural areas) and the relationship of some of the factors that may lead to overweight and obesity in Saudi Arabia. There were 300 (150 males and 150 females) high school senior grade level students, recruited from the urban city of Riyadh and 300 high school students recruited from the rural areas of Dawadami (150 males and 150 females). Approval for this study was given …


Sp743-C Advance Directives, Alan B. Galloway, Jane Howell Starnes Dec 2012

Sp743-C Advance Directives, Alan B. Galloway, Jane Howell Starnes

Marketing, Finances and Value-Added Agriculture

No abstract provided.


Sp743-D Power Of Attorney, Alan B. Galloway, Christopher Clark, Jane Howell Starnes Dec 2012

Sp743-D Power Of Attorney, Alan B. Galloway, Christopher Clark, Jane Howell Starnes

Marketing, Finances and Value-Added Agriculture

No abstract provided.


Crystal Structures And Kinetics Of Monofunctional Proline Dehydrogenase Provide Insight Into Substrate Recognition And Conformational Changes Associated With Flavin Reduction And Product Release, Min Luo, Benjamin W. Arentson, Dhiraj Srivastava, Donald F. Becker, John J. Tanner Dec 2012

Crystal Structures And Kinetics Of Monofunctional Proline Dehydrogenase Provide Insight Into Substrate Recognition And Conformational Changes Associated With Flavin Reduction And Product Release, Min Luo, Benjamin W. Arentson, Dhiraj Srivastava, Donald F. Becker, John J. Tanner

Department of Biochemistry: Faculty Publications

Proline dehydrogenase catalyzes the FAD-dependent oxidation of proline to Δ1- pyrroline-5- carboxylate, which is the first step of proline catabolism. Here, we report the structures of proline dehydrogenase from Deinococcus radiodurans in the oxidized state complexed with the proline analog L-tetrahydrofuroic acid and in the reduced state with the proline site vacant. The analog binds against the si face of the FAD isoalloxazine and is protected from bulk solvent by the α8 helix and the β1-α1 loop. The FAD ribityl chain adopts two conformations in the E-S complex, which is unprecedented for flavoenzymes. One of the conformations is novel for …


U.S. Drought Monitor, December 11, 2012, Rich Tinker Dec 2012

U.S. Drought Monitor, December 11, 2012, Rich Tinker

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 11, 2012 (12/11/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


Compositions And Methods For Synergistic Manipulation Of Plant And Insect Defenses, Graham Moores, Georgina Bingham Dec 2012

Compositions And Methods For Synergistic Manipulation Of Plant And Insect Defenses, Graham Moores, Georgina Bingham

Department of Entomology: Faculty Publications

This invention relates to the control of plant pests, such as aphid and whitefly by treating plants with a compound which inhibits the plant pests ability to overcome plant defense responses, such as piperonyl butoxide or propyl gallate, in combination with a compound which activates plant defense responses, such as cis-Jasmone or beta-aminobutyric acid.


Adenosine Deaminase Enhances The Immunogenicity Of Human Dendritic Cells From Healthy And Hiv-Infected Individuals, Víctor Casanova, Isaac Isaac Naval-Macabuhay, Marta Massanella, Marta Rodríguez-García Dec 2012

Adenosine Deaminase Enhances The Immunogenicity Of Human Dendritic Cells From Healthy And Hiv-Infected Individuals, Víctor Casanova, Isaac Isaac Naval-Macabuhay, Marta Massanella, Marta Rodríguez-García

Dartmouth Scholarship

ADA is an enzyme implicated in purine metabolism, and is critical to ensure normal immune function. Its congenital deficit leads to severe combined immunodeficiency (SCID). ADA binding to adenosine receptors on dendritic cell surface enables T-cell costimulation through CD26 crosslinking, which enhances T-cell activation and proliferation. Despite a large body of work on the actions of the ecto-enzyme ADA on T-cell activation, questions arise on whether ADA can also modulate dendritic cell maturation. To this end we investigated the effects of ADA on human monocyte derived dendritic cell biology. Our results show that both the enzymatic and non-enzymatic activities of …


Walmart's Sustainability Journey: Peter Redmond And The Search For Sustainable Seafood, David G. Hyatt Dec 2012

Walmart's Sustainability Journey: Peter Redmond And The Search For Sustainable Seafood, David G. Hyatt

Wal-Mart Sustainability Case Project

In “Peter Redmond and the Search for Sustainable Seafood,” students examine the responses of Peter Redmond, Vice President and Divisional Merchandise Manager of Deli and Seafood, to organizational pressures to make seafood more sustainable at Walmart.


Doublesex Target Genes In The Red Flour Beetle, Tribolium Castaneum, Jayendra Nath Shukla, Subba Reddy Palli Dec 2012

Doublesex Target Genes In The Red Flour Beetle, Tribolium Castaneum, Jayendra Nath Shukla, Subba Reddy Palli

Entomology Faculty Publications

Sex determination cascade in insects terminates with the production of sex-specific protein, Doublesex (Dsx). We identified the dsx homolog (Tcdsx) in Tribolium castaneum. The pre-mRNA of Tcdsx is sex-specifically spliced into three female (Tcdsxf1, Tcdsxf2 and Tcdsxf3) and one male-specific (Tcdsxm) isoforms. Cis-regulatory elements potentially involved in sex-specific splicing of the Tcdsx pre-mRNA were identified in the female-specific exon and the adjoining intronic sequences. All the three female-specific TcDsx proteins share common OD1 and OD2 domains and differ in their C-terminal sequences. Knockdown of Tcdsx resulted in a reduction in the oocyte development, egg production and hatching of eggs laid. …


Transcriptional Response Of Two Core Photosystem Genes In Symbiodinium Spp. Exposed To Thermal Stress, Michael P. Mcginley, Matthew D. Aschaffenburg, Daniel D. Pettay, Robin T. Smith, Todd C. Lajeunesse, Mark E. Warner Dec 2012

Transcriptional Response Of Two Core Photosystem Genes In Symbiodinium Spp. Exposed To Thermal Stress, Michael P. Mcginley, Matthew D. Aschaffenburg, Daniel D. Pettay, Robin T. Smith, Todd C. Lajeunesse, Mark E. Warner

Department of Biological Sciences

Mutualistic symbioses between scleractinian corals and endosymbiotic dinoflagellates (Symbiodinium spp.) are the foundation of coral reef ecosystems. For many coral-algal symbioses, prolonged episodes of thermal stress damage the symbiont's photosynthetic capability, resulting in its expulsion from the host. Despite the link between photosynthetic competency and symbiont expulsion, little is known about the effect of thermal stress on the expression of photosystem genes in Symbiodinium. This study used real-time PCR to monitor the transcript abundance of two important photosynthetic reaction center genes, psbA(encoding the D1 protein of photosystem II) and psaA (encoding the P700 protein of photosystem I), …


Characterization Of Atlantic Cod Spawning Habitat And Behavior In Icelandic Coastal Waters, Timothy B. Grabowski, Kevin M. Boswell, Bruce J. Mcadam, R.J. David Wells, Guđrún Marteinsdóttir Dec 2012

Characterization Of Atlantic Cod Spawning Habitat And Behavior In Icelandic Coastal Waters, Timothy B. Grabowski, Kevin M. Boswell, Bruce J. Mcadam, R.J. David Wells, Guđrún Marteinsdóttir

Department of Biological Sciences

The physical habitat used during spawning may potentially be an important factor affecting reproductive output of broadcast spawning marine fishes, particularly for species with complex, substrate-oriented mating systems and behaviors, such as Atlantic cod Gadus morhua. We characterized the habitat use and behavior of spawning Atlantic cod at two locations off the coast of southwestern Iceland during a 2-d research cruise (15–16 April 2009). We simultaneously operated two different active hydroacoustic gear types, a split beam echosounder and a dual frequency imaging sonar (DIDSON), as well as a remotely operated underwater vehicle (ROV). A total of five fish species were …


Final Environmental Data Report December 2012: Technical Support Document For The 2013 State Of Our Estuaries Report, Piscataqua Region Estuaries Partnership Dec 2012

Final Environmental Data Report December 2012: Technical Support Document For The 2013 State Of Our Estuaries Report, Piscataqua Region Estuaries Partnership

PREP Reports & Publications

The Piscataqua Region Estuaries Partnership (PREP) is part of the U.S. Environmental Protection Agency’s National Estuary Program, which is a joint local/state/federal program established under the Clean Water Act with the goal of protecting and enhancing nationally significant estuarine resources. PREP is funded by the EPA and is administered by the University of New Hampshire.

The following sections contain the most recent data for the indicators currently tracked by PREP.


News Of The Department Of Animal Science, Department Of Animal Science Dec 2012

News Of The Department Of Animal Science, Department Of Animal Science

Animal Science Newsletters

No abstract provided.


Reactive Oxygen Species Production And Brugia Pahangi Survivorship In Aedes Polynesiensis With Artificial Wolbachia Infection Types, Elizabeth S. Andrews, Philip R. Crain, Yuqing Fu, Daniel K. Howe, Stephen L. Dobson Dec 2012

Reactive Oxygen Species Production And Brugia Pahangi Survivorship In Aedes Polynesiensis With Artificial Wolbachia Infection Types, Elizabeth S. Andrews, Philip R. Crain, Yuqing Fu, Daniel K. Howe, Stephen L. Dobson

Entomology Faculty Publications

Heterologous transinfection with the endosymbiotic bacterium Wolbachia has been shown previously to induce pathogen interference phenotypes in mosquito hosts. Here we examine an artificially infected strain of Aedes polynesiensis, the primary vector of Wuchereria bancrofti, which is the causative agent of Lymphatic filariasis (LF) throughout much of the South Pacific. Embryonic microinjection was used to transfer the wAlbB infection from Aedes albopictus into an aposymbiotic strain of Ae. polynesiensis. The resulting strain (designated "MTB") experiences a stable artificial infection with high maternal inheritance. Reciprocal crosses of MTB with naturally infected wild-type Ae. polynesiensis demonstrate strong bidirectional incompatibility. Levels of reactive …


Agenda: The Future Of Natural Resources Policy, University Of Colorado Boulder. Natural Resources Law Center Dec 2012

Agenda: The Future Of Natural Resources Policy, University Of Colorado Boulder. Natural Resources Law Center

The Future of Natural Resources Policy (December 6)

This forum will provide a post-election perspective on some of the challenges and opportunities that natural resources, public lands, and energy policymakers in Washington are likely to face in the next four years. An expert panel will discuss the dynamics in the Department of the Interior, the Department of Agriculture, and Congress, and how their evolving policies are likely to affect Colorado in the coming years.

Moderator: Dean Phil Weiser, University of Colorado Law School

Panelists:

Jay Jensen, Associate Director for Land & Water Ecosystems, White House Council on Environmental Quality

Scott Miller, Visiting Assistant Professor, University of Colorado Law …


Background Reading: Department Of Agriculture, 2013 Budget Overview, United States. Forest Service, United States. Department Of Agriculture Dec 2012

Background Reading: Department Of Agriculture, 2013 Budget Overview, United States. Forest Service, United States. Department Of Agriculture

The Future of Natural Resources Policy (December 6)

57 pages.

"Fiscal Year 2013 Budget Overview"

"February 2012"

"Background Reading"

The Future of Natural Resources Policy: This forum will provide a post-election perspective on some of the challenges and opportunities that natural resources, public lands, and energy policymakers in Washington are likely to face in the next four years. An expert panel will discuss the dynamics in the Department of the Interior, the Department of Agriculture, and Congress, and how their evolving policies are likely to affect Colorado in the coming years.


Molecular Characterization Of A Tetraspanin From The Human Liver Fluke, Opisthorchis Viverrini, Supawadee Piratae, Smarn Tesana, Malcolm K. Jones, Paul J. Brindley, Alex Loukas, Erica Lovas, Veerachai Eursitthichai, Banchob Sripa, Sirikanda Thanasuwan, Thewarach Laha Dec 2012

Molecular Characterization Of A Tetraspanin From The Human Liver Fluke, Opisthorchis Viverrini, Supawadee Piratae, Smarn Tesana, Malcolm K. Jones, Paul J. Brindley, Alex Loukas, Erica Lovas, Veerachai Eursitthichai, Banchob Sripa, Sirikanda Thanasuwan, Thewarach Laha

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

The human liver fluke, Opisthorchis viverrini, is designated as a group 1 carcinogen, and is the major risk factor for cholangiocarcinoma in endemic countries throughout Southeast Asia. Proteins in the excretory-secretory products and tegumental surface membranes of the fluke have been proposed to play pivotal roles in parasite survival in the host, and subsequent pathogenesis. These macromolecules are therefore valid targets for the development of vaccines and new drugs to control the infection. Tetraspanins (TSP) are prominent components of the tegument of blood flukes where they are essential for tegument formation, are directly exposed to the immune system, …


A Hunter Virus That Targets Both Infected Cells And Hiv Free Virions: Implications For Therapy, Cody Greer, Gisela García-Ramos Dec 2012

A Hunter Virus That Targets Both Infected Cells And Hiv Free Virions: Implications For Therapy, Cody Greer, Gisela García-Ramos

Biology Faculty Publications

The design of 'hunter' viruses aimed at destroying human immunodeficiency virus (HIV) infected cells is an active area of research that has produced promising results in vitro. Hunters are designed to target exposed viral envelope proteins in the membranes of infected cells, but there is evidence that the hunter may also target envelope proteins of free HIV, inducing virus-virus fusion. In order to predict the effects of this fusion on therapy outcomes and determine whether fusion ability is advantageous for hunter virus design, we have constructed a model to account for the possibility of hunter-HIV fusion. The study was based …


Selection Of Trna Charging Quality Control Mechanisms That Increase Mistranslation Of The Genetic Code, Srujana S. Yadavalli, Michael Ibba Dec 2012

Selection Of Trna Charging Quality Control Mechanisms That Increase Mistranslation Of The Genetic Code, Srujana S. Yadavalli, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Mistranslation can follow two events during protein synthesis: production of non-cognate amino acid:transfer RNA (tRNA) pairs by aminoacyl-tRNA synthetases (aaRSs) and inaccurate selection of aminoacyl-tRNAs by the ribosome. Many aaRSs actively edit non-cognate amino acids, but editing mechanisms are not evolutionarily conserved, and their physiological significance remains unclear. To address the connection between aaRSs and mistranslation, the evolutionary divergence of tyrosine editing by phenylalanyl-tRNA synthetase (PheRS) was used as a model. Certain PheRSs are naturally error prone, most notably a Mycoplasma example that displayed a low level of specificity consistent with elevated mistranslation of the proteome. Mycoplasma PheRS was found …


Leptin Differentially Regulate Stat3 Activation In Ob/Ob Mouse Adipose Mesenchymal Stem Cells, Zhou Zhou, Manish Neupane, Hui R. Zhou, Dayong Wu, Chia-Cheng Chang, Naima Moustaid-Moussa, Kate J. Claycomb Dec 2012

Leptin Differentially Regulate Stat3 Activation In Ob/Ob Mouse Adipose Mesenchymal Stem Cells, Zhou Zhou, Manish Neupane, Hui R. Zhou, Dayong Wu, Chia-Cheng Chang, Naima Moustaid-Moussa, Kate J. Claycomb

Animal Science Publications and Other Works

Background

Leptin-deficient ob/ob mice exhibit adipocyte hypertrophy and hyperplasia as well as elevated adipose tissue and systemic inflammation. Multipotent stem cells isolated from adult adipose tissue can differentiate into adipocytes ex vivo and thereby contribute toward increased adipocyte cell numbers, obesity, and inflamm ation. Currently, information is lacking regarding regulation of adipose stem cell numbers as well as leptin-induced inflammation and its signaling pathway in ob/ob mice.

Methods

Using leptin deficient ob/ob mice, we investigated whether leptin injection into ob/ob mice increases adipose stem cell numbers and adipose tissue inflammatory marker MCP-1 mRNA and secretion levels. We also determined leptin …