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Full-Text Articles in Life Sciences

Toward Target 2 Of The Global Strategy For Plant Conservation: An Expert Analysis Of The Puerto Rican Flora To Validate New Streamlined Methods For Assessing Conservation Status, James S. Miller, Gary A. Krupnick, Hannah Stevens, Holly Porter-Morgan, Brian Boom, Pedro Acevedo-Rodríguez, James Ackerman, Duane Kolterman, Eugenio Santiago, Christian Torres, Jeanine Velez Dec 2013

Toward Target 2 Of The Global Strategy For Plant Conservation: An Expert Analysis Of The Puerto Rican Flora To Validate New Streamlined Methods For Assessing Conservation Status, James S. Miller, Gary A. Krupnick, Hannah Stevens, Holly Porter-Morgan, Brian Boom, Pedro Acevedo-Rodríguez, James Ackerman, Duane Kolterman, Eugenio Santiago, Christian Torres, Jeanine Velez

Publications and Research

Target 2 of the 2020 Global Strategy for Plant Conservation (GSPC) calls for a comprehensive list of the world's threatened plant species. The lack of such a list is one of the greatest impediments to protecting the full complement of the world's plant species, and work to achieve this has been slow. An efficient system for identifying those species that are at risk of extinction could help to achieve this goal in a time frame sensitive to today's conservation needs. Two systems that efficiently use available data to assess conservation status were tested against a provisional International Union for Conservation …


Transformation Of Stimulus Correlations By The Retina, Kristina D. Simmons, Jason Prentice, Gašper Tkačik, Jan Homann, Heather K. Yee, Stephanie E. Palmer, Philip C. Nelson, Vijay Balasubramanian Dec 2013

Transformation Of Stimulus Correlations By The Retina, Kristina D. Simmons, Jason Prentice, Gašper Tkačik, Jan Homann, Heather K. Yee, Stephanie E. Palmer, Philip C. Nelson, Vijay Balasubramanian

Publications and Research

Redundancies and correlations in the responses of sensory neurons may seem to waste neural resources, but they can also carry cues about structured stimuli and may help the brain to correct for response errors. To investigate the effect of stimulus structure on redundancy in retina, we measured simultaneous responses from populations of retinal ganglion cells presented with natural and artificial stimuli that varied greatly in correlation structure; these stimuli and recordings are publicly available online. Responding to spatio-temporally structured stimuli such as natural movies, pairs of ganglion cells were modestly more correlated than in response to white noise checkerboards, but …


Microfluidic Generated Egf-Gradients Induce Chemokinesis Of Transplantable Retinal Progenitor Cells Via The Jak/Stat And Pi3kinase Signaling Pathways, Uchenna J. Unachukwu, Moira Sauane, Maribel Vazquez, Stephen Redenti Dec 2013

Microfluidic Generated Egf-Gradients Induce Chemokinesis Of Transplantable Retinal Progenitor Cells Via The Jak/Stat And Pi3kinase Signaling Pathways, Uchenna J. Unachukwu, Moira Sauane, Maribel Vazquez, Stephen Redenti

Publications and Research

A growing number of studies are evaluating retinal progenitor cell (RPC) transplantation as an approach to repair retinal degeneration and restore visual function. To advance cell-replacement strategies for a practical retinal therapy, it is important to define the molecular and biochemical mechanisms guiding RPC motility. We have analyzed RPC expression of the epidermal growth factor receptor (EGFR) and evaluated whether exposure to epidermal growth factor (EGF) can coordinate motogenic activity in vitro. Using Boyden chamber analysis as an initial highthroughput screen, we determined that RPC motility was optimally stimulated by EGF concentrations in the range of 20-400ng/ml, with decreased stimulation …


Communication And Common Interest, Peter Godfrey-Smith, Manolo Martínez Nov 2013

Communication And Common Interest, Peter Godfrey-Smith, Manolo Martínez

Publications and Research

Explaining the maintenance of communicative behavior in the face of incentives to deceive, conceal information, or exaggerate is an important problem in behavioral biology. When the interests of agents diverge, some form of signal cost is often seen as essential to maintaining honesty. Here, novel computational methods are used to investigate the role of common interest between the sender and receiver of messages in maintaining cost-free informative signaling in a signaling game. Two measures of common interest are defined. These quantify the divergence between sender and receiver in their preference orderings over acts the receiver might perform in each state …


Are Characiform Fishes Gondwanan In Origin? Insights From A Time-Scaled Molecular Phylogeny Of The Citharinoidei (Ostariophysi: Characiformes), Jairo Arroyave, John S. S. Denton, Melanie L. J. Stiassny Oct 2013

Are Characiform Fishes Gondwanan In Origin? Insights From A Time-Scaled Molecular Phylogeny Of The Citharinoidei (Ostariophysi: Characiformes), Jairo Arroyave, John S. S. Denton, Melanie L. J. Stiassny

Publications and Research

Fishes of the order Characiformes are a diverse and economically important teleost clade whose extant members are found exclusively in African and Neotropical freshwaters. Although their transatlantic distribution has been primarily attributed to the Early Cretaceous fragmentation of western Gondwana, vicariance has not been tested with temporal information beyond that contained in their fragmentary fossil record and a recent time-scaled phylogeny focused on the African family Alestidae. Because members of the suborder Citharinoidei constitute the sister lineage to the entire remaining Afro-Neotropical characiform radiation, we inferred a time-calibrated molecular phylogeny of citharinoids using a popular Bayesian approach to molecular dating …


Cervicothoracic Multisegmental Transpinal Evoked Potentials In Humans, Jonathan Einhorn, Alan Li, Royi Hazan, Maria Knikou Oct 2013

Cervicothoracic Multisegmental Transpinal Evoked Potentials In Humans, Jonathan Einhorn, Alan Li, Royi Hazan, Maria Knikou

Publications and Research

The objectives of this study were to establish the neurophysiological properties of the transpinal evoked potentials (TEPs) following transcutaneous electric stimulation of the spine (tsESS) over the cervicothoracic region, changes in the amplitude of the TEPs preceded by median nerve stimulation at group I threshold, and the effects of tsESS on the flexor carpi radialis (FCR) H-reflex in thirteen healthy human subjects while seated. Two re-usable self-adhering electrodes, connected to function as one electrode (cathode), were placed bilaterally on the clavicles. A re-usable electrode (anode) was placed on the cervicothoracic region covering from Cervical 4 – Thoracic 2 and held …


Fast Quantitative Real-Time Pcr-Based Screening For Common Chromosomal Aneuploidies In Mouse Embryonic Stem Cells, Charlotte D'Hulst, Irena Parvanova, Delia Tomoiaga, Maria L. Sapar, Paul Feinstein Sep 2013

Fast Quantitative Real-Time Pcr-Based Screening For Common Chromosomal Aneuploidies In Mouse Embryonic Stem Cells, Charlotte D'Hulst, Irena Parvanova, Delia Tomoiaga, Maria L. Sapar, Paul Feinstein

Publications and Research

Chromosomal integrity has been known for many years to affect the ability of mouse embryonic stem cells (mESCs) to contribute to the germline of chimeric mice. Abnormal chromosomes are generally detected by standard cytogenetic karyotyping. However, this method is expensive, time consuming, and often omitted prior to blastocyst injection, consequently reducing the frequency of mESC-derived offspring. Here, we show a fast, accurate, and inexpensive screen for identifying the two most common aneuploidies (Trisomy 8 and loss of chromosome Y) in genetically manipulated mESCs using quantitative real-time PCR (qPCR). Screening against these two aneuploidies significantly increases the fraction of normal mESC …


Signatures Of Rapid Evolution In Urban And Rural Transcriptomes Of White-Footed Mice (Peromyscus Leucopus) In The New York Metropolitan Area, Stephen Edward Harris, Jason Munshi-South, Craig Oberfell, Rachel O'Neill Aug 2013

Signatures Of Rapid Evolution In Urban And Rural Transcriptomes Of White-Footed Mice (Peromyscus Leucopus) In The New York Metropolitan Area, Stephen Edward Harris, Jason Munshi-South, Craig Oberfell, Rachel O'Neill

Publications and Research

Urbanization is a major cause of ecological degradation around the world, and human settlement in large cities is accelerating. New York City (NYC) is one of the oldest and most urbanized cities in North America, but still maintains 20% vegetation cover and substantial populations of some native wildlife. The white-footed mouse, Peromyscus leucopus, is a common resident of NYC’s forest fragments and an emerging model system for examining the evolutionary consequences of urbanization. In this study, we developed transcriptomic resources for urban P. leucopus to examine evolutionary changes in protein-coding regions for an exemplar “urban adapter.” We used Roche 454 …


Genome-Wide Analyses Of Shavenbaby Target Genes Reveals Distinct Features Of Enhancer Organization, Delphine Menoret, Marc Santolini, Isabelle Fernandes, Rebecca Spokony, Jennifer Zanet, Ignacio Gonzalez, Yvan Latapie, Pierre Ferrer, Hervé Rouault, Kevin P. White, Philippe Besse, Vincent Hakim, Stein Aerts, Francois Payre, Serge Plaza Aug 2013

Genome-Wide Analyses Of Shavenbaby Target Genes Reveals Distinct Features Of Enhancer Organization, Delphine Menoret, Marc Santolini, Isabelle Fernandes, Rebecca Spokony, Jennifer Zanet, Ignacio Gonzalez, Yvan Latapie, Pierre Ferrer, Hervé Rouault, Kevin P. White, Philippe Besse, Vincent Hakim, Stein Aerts, Francois Payre, Serge Plaza

Publications and Research

Background: Developmental programs are implemented by regulatory interactions between Transcription Factors (TFs) and their target genes, which remain poorly understood. While recent studies have focused on regulatory cascades of TFs that govern early development, little is known about how the ultimate effectors of cell differentiation are selected and controlled. We addressed this question during late Drosophila embryogenesis, when the finely tuned expression of the TF Ovo/Shavenbaby (Svb) triggers the morphological differentiation of epidermal trichomes.

Results: We defined a sizeable set of genes downstream of Svb and used in vivo assays to delineate 14 enhancers driving their specific expression in trichome …


Taxonomic Revision Of The Olingos (Bassaricyon), With Description Of A New Species, The Olinguito, Kristofer M. Helgen, C. Miguel Pinto, Roland Kays, Laura E. Helgen, Mirian T. N. Tsuchiya, Aleta Quinn, Don E. Wilson, Jesús E. Maldonado Aug 2013

Taxonomic Revision Of The Olingos (Bassaricyon), With Description Of A New Species, The Olinguito, Kristofer M. Helgen, C. Miguel Pinto, Roland Kays, Laura E. Helgen, Mirian T. N. Tsuchiya, Aleta Quinn, Don E. Wilson, Jesús E. Maldonado

Publications and Research

We present the first comprehensive taxonomic revision and review the biology of the olingos, the endemic Neotropical procyonid genus Bassaricyon, based on most specimens available in museums, and with data derived from anatomy, morphometrics, mitochondrial and nuclear DNA, field observations, and geographic range modeling. Species of Bassaricyon are primarily forest-living, arboreal, nocturnal, frugivorous, and solitary, and have one young at a time. We demonstrate that four olingo species can be recognized, including a Central American species (B. gabbii), lowland species with eastern, cis-Andean (B. alleni) and western, trans- Andean (B. medius) distributions, and a species endemic to cloud forests in …


Candidatus Syngnamydia Venezia, A Novel Member Of The Phylum Chlamydiae From The Broad Nosed Pipefish, Syngnathustyphle Typhle, Alexander Fehr, Elisabeth Walther, Heike Schmidt-Posthaus, Lisbeth Nufer, Anthony B. Wilson, Miroslav Svercel, Denis Richter, Helmut Segner, Andreas Pospischil, Lloyd Vaughan Aug 2013

Candidatus Syngnamydia Venezia, A Novel Member Of The Phylum Chlamydiae From The Broad Nosed Pipefish, Syngnathustyphle Typhle, Alexander Fehr, Elisabeth Walther, Heike Schmidt-Posthaus, Lisbeth Nufer, Anthony B. Wilson, Miroslav Svercel, Denis Richter, Helmut Segner, Andreas Pospischil, Lloyd Vaughan

Publications and Research

Chlamydia are obligate intracellular bacteria and important pathogens of humans and animals. Chlamydia-related bacteria are also major fish pathogens, infecting epithelial cells of the gills and skin to cause the disease epitheliocystis. Given the wide distribution, ancient origins and spectacular diversity of bony fishes, this group offers a rich resource for the identification and isolation of novel Chlamydia. The broad-nosed pipefish (Syngnathus typhle) is a widely distributed and genetically diverse temperate fish species, susceptible to epitheliocystis across much of its range. We describe here a new bacterial species, Candidatus Syngnamydia venezia; epitheliocystis agent of S. typhle and close relative to …


Steered Molecular Dynamics Simulations Of A Type Iv Pilus Probe Initial Stages Of A Force-Induced Conformational Transition, Joseph L. Baker, Nicolas Biais, Florence Tama Apr 2013

Steered Molecular Dynamics Simulations Of A Type Iv Pilus Probe Initial Stages Of A Force-Induced Conformational Transition, Joseph L. Baker, Nicolas Biais, Florence Tama

Publications and Research

Type IV pili are long, protein filaments built from a repeating subunit that protrudes from the surface of a wide variety of infectious bacteria. They are implicated in a vast array of functions, ranging from bacterial motility to microcolony formation to infection. One of the most well-studied type IV filaments is the gonococcal type IV pilus (GC-T4P) from Neisseria gonorrhoeae, the causative agent of gonorrhea. Cryo-electron microscopy has been used to construct a model of this filament, offering insights into the structure of type IV pili. In addition, experiments have demonstrated that GC-T4P can withstand very large tension forces, and …


Edges And Overlaps In Northwest Atlantic Phylogeography, Safra Altman, John D. Robinson, James M. Pringle, James E. Byers, John P. Wares Apr 2013

Edges And Overlaps In Northwest Atlantic Phylogeography, Safra Altman, John D. Robinson, James M. Pringle, James E. Byers, John P. Wares

Publications and Research

As marine environments change, the greatest ecological shifts—including resource usage and species interactions—are likely to take place in or near regions of biogeographic and phylogeographic transition. However, our understanding of where these transitional regions exist depends on the defining criteria. Here we evaluate phylogeographic transitions using a bootstrapping procedure that allows us to focus on either the strongest genetic transitions between a pair of contiguous populations, versus evaluation of transitions inclusive of the entire overlap between two intraspecific genetic lineages. We compiled data for the Atlantic coast of the United States, and evaluate taxa with short- and long-dispersing larval phases …


Isoflurane Increases Neuronal Cell Death Vulnerability By Downregulating Mir-214, Hailiang Yan, Tao Xu, Hongfeng Zhao, Kuo-Chieh Lee, Hoau-Yan Wang, Yan Zhang Feb 2013

Isoflurane Increases Neuronal Cell Death Vulnerability By Downregulating Mir-214, Hailiang Yan, Tao Xu, Hongfeng Zhao, Kuo-Chieh Lee, Hoau-Yan Wang, Yan Zhang

Publications and Research

Since accumulating evidence suggests the application of anesthetics may increase the risk of Alzheimer’s disease (AD), we investigated the cytotoxicity of inhaled general anesthesia in neurons and its underlying mechanism. Using primary cultured rat hippocampal neurons as the study model, here we show that isoflurane increases vulnerability to intracellular or extracellular amyloid b with or without serum deprivation. This isoflurane-induced effect is mediated by the downregulation of miR-214 level that lead to an elevated expression of Bax, a prominent target for miR-214. We conclude that isoflurane increases cell death in the presence of amyloid b by increasing Bax level through …


The Passiflora Tripartita (Banana Passion) Fruit: A Source Of Bioactive Flavonoid C-Glycosides Isolated By Hsccc And Characterized By Hplc–Dad–Esi/Ms/Ms, Mario J. Simirgiotis, Guillermo Schmeda-Hirschmann, Jorge Bórquez, Edward J. Kennelly Jan 2013

The Passiflora Tripartita (Banana Passion) Fruit: A Source Of Bioactive Flavonoid C-Glycosides Isolated By Hsccc And Characterized By Hplc–Dad–Esi/Ms/Ms, Mario J. Simirgiotis, Guillermo Schmeda-Hirschmann, Jorge Bórquez, Edward J. Kennelly

Publications and Research

The banana passion fruit (Passiflora tripartita Breiter, Passifloraceae) known as “tumbo” is very appreciated in tropical and subtropical countries of South America. Methanolic extracts from peel and the fruit juice of P. tripartita growing in Chile were analyzed for antioxidant capacity as well as for flavonoid and phenolic content. A chromatographic method was developed for the rapid identification of the main phenolics in the samples by HPLC-DAD and HPLC-MS. The fast fingerprint analysis allowed the detection of eighteen flavonoid C-glycosides and four flavonoid O-glycoside derivatives which were characterized by UV spectra and ESI-MS-MS analysis. Several of the C-glycosides detected are …


Changes In Natural Killer Cell Activation And Function During Primary Hiv-1 Infection, Vivek Naranbhai, Marcus Altfeld, Salim S. Abdool Karim, Thumbi Ndung’U, Quarraisha Abdool Karim, William H. Carr Jan 2013

Changes In Natural Killer Cell Activation And Function During Primary Hiv-1 Infection, Vivek Naranbhai, Marcus Altfeld, Salim S. Abdool Karim, Thumbi Ndung’U, Quarraisha Abdool Karim, William H. Carr

Publications and Research

Background: Recent reports suggest that Natural Killer (NK) cells may modulate pathogenesis of primary HIV-1 infection. However, HIV dysregulates NK-cell responses. We dissected this bi-directional relationship to understand how HIV impacts NK-cell responses during primary HIV-1 infection.

Methodology/Principal Findings: Paired samples from 41 high-risk, initially HIV-uninfected CAPRISA004 participants were analysed prior to HIV acquisition, and during viraemic primary HIV-1 infection. At the time of sampling post-infection five women were seronegative, 11 women were serodiscordant, and 25 women were seropositive by HIV-1 rapid immunoassay. Flow cytometry was used to measure NK and T-cell activation, NK-cell receptor expression, cytotoxic and cytokine-secretory functions, …


Panama Trip Will Explore Biodiversity Hotspot, Aldemaro Romero Jr. Jan 2013

Panama Trip Will Explore Biodiversity Hotspot, Aldemaro Romero Jr.

Publications and Research

No abstract provided.


Carcass Feeding For Captive Vultures: Testing Assumptions About Zoos And Effects On Birds And Visitors, Hannah Gaengler Jan 2013

Carcass Feeding For Captive Vultures: Testing Assumptions About Zoos And Effects On Birds And Visitors, Hannah Gaengler

Dissertations and Theses

Carcass feeding is a potentially controversial feeding method for zoo animals. The common assumption is that many North American zoos refrain from feeding large carcasses to their carnivorous animals because zoo visitors might not approve of this feeding method. However, since there are several species of carnivores in zoos that feed from large carcasses in nature, this food type also has the potential to be beneficial to their welfare. In intelligent and usually inquisitive scavengers like vultures, a lack of activity and behavioral opportunities could be a welfare problem in captivity; providing them with a more complex food item might …


The Expression Of The Transcription Factor Broad And Rna-Binding Factors In The Midgut Of The Mosquito Aedes Aegypti During Metamorphosis, Kathryn Ray Jan 2013

The Expression Of The Transcription Factor Broad And Rna-Binding Factors In The Midgut Of The Mosquito Aedes Aegypti During Metamorphosis, Kathryn Ray

Dissertations, Theses, and Capstone Projects

Transcription factors, microRNAs and RNA binding factors frequently interact to coordinate gene expression during development. The transcription factor BROAD (BR) is a global regulator of insect gene transcription and governs the timing of the commitment to pupate. I determined BR expression in the Ae. aegypti midgut by qPCR, and correlated its expression with that of nine miRNAs and three RNA-binding factors. During midgut metamorphosis the expression of these factors was dynamic and reproducible.

To better understand the changes in expression patterns, I evaluated the effects of hormone analogs on expression. Using this approach I uncovered concurrent up-regulation of BR, miR-34 …


Medicinal Plants Of Northern Thailand For The Treatment Of Cognitive Impairment In The Elderly, Lisa C. Offringa Jan 2013

Medicinal Plants Of Northern Thailand For The Treatment Of Cognitive Impairment In The Elderly, Lisa C. Offringa

Dissertations, Theses, and Capstone Projects

Dementia is a progressive neurological disease affecting memory and behavior. The diagnosis of dementia is increasing exponentially worldwide and with it the potential risk for a severe social and economic burden of caring for an increasing debilitated elderly population. Cognitive impairment, and especially memory loss, can be the first indication of dementia. This study documents the treatment of cognitive impairment in the elderly by Thai traditional healers in northern Thailand usingmedicinal plants. Interviews were conducted from 2008-2012 to investigate the etiology of dementia in Thai Traditional Medicine and identify plants used to treat memory loss in the pharmacopeia of northern …


Understanding A Pest: Phylogeography And Systematics Of The Plum Curculio (Conotrachelus Nenuphar), Samuel N. Crane Jan 2013

Understanding A Pest: Phylogeography And Systematics Of The Plum Curculio (Conotrachelus Nenuphar), Samuel N. Crane

Dissertations, Theses, and Capstone Projects

The plum curculio (Conotrachelus nenuphar Herbst) (Coleoptera: Curculionidae) is an economically and ecologically important pest in North America but is understudied despite having a long history in the scientific literature. Its chemical ecology, life history habits, and distribution are all well characterized. However, there is a dearth of knowledge concerning the population structure and evolutionary history of the species. This study aims to use methods from evolutionary biology to better understand an agricultural pest species and provide tools to aid in its management.

Existing taxonomic classifications of North American Conotrachelus species have been tested for the first time. Using …


Diversity, Resource Partitioning, And Species Turnover In Neotropical Saproxylic Beetles (Coleoptera: Cerambycidae, Curculionidae) Associated With Trees In The Brazil Nut Family (Lecythidaceae), Joyce Lynn Fassbender Jan 2013

Diversity, Resource Partitioning, And Species Turnover In Neotropical Saproxylic Beetles (Coleoptera: Cerambycidae, Curculionidae) Associated With Trees In The Brazil Nut Family (Lecythidaceae), Joyce Lynn Fassbender

Dissertations, Theses, and Capstone Projects

Deforestation and global changes in temperature and moisture associated with rising levels of greenhouse gases are expected to have strong, direct effects on abundance of wood-boring beetles through loss of larval feeding substrates, and indirect effects through climate and microclimate change. This dissertation examines Neotropical saproxylic beetle (Coleoptera: Curculionidae) diversity, niche breadth, and resource partitioning, and predicts possible impacts of climate change. Data from beetle rearing experiments conducted in French Guiana and Peru were analyzed to assess species richness, abundance, host specificity, seasonality and stratification of wood-boring beetles associated with the Brazil nut family (Lecythidaceae). Niche stability was assessed over …