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Matrix Metalloproteinases, New Insights Into The Understanding Of Neurodegenerative Disorders, Yoon-Seong Kim, Tong J. Joh Jan 2012

Matrix Metalloproteinases, New Insights Into The Understanding Of Neurodegenerative Disorders, Yoon-Seong Kim, Tong J. Joh

Faculty Bibliography 2010s

Matrix metalloproteinases (MMPs) are a subfamily of zinc-dependent proteases that are re-sponsible for degradation and remodeling of extracellular matrix proteins. The activity of MMPs is tightly regulated at several levels including cleavage of prodomain, allosteric activation, com-partmentalization and complex formation with tissue inhibitor of metalloproteinases (TIMPs). In the central nervous system (CNS), MMPs play a wide variety of roles ranging from brain devel-opment, synaptic plasticity and repair after injury to the pathogenesis of various brain disorders. Following general discussion on the domain structure and the regulation of activity of MMPs, we emphasize their implication in various brain disorder conditions such …

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Purification, Crystallization And X-Ray Diffraction Analysis Of Human Dynamin-Related Protein 1 Gtpase-Ged Fusion Protein, Eva Klinglmayr, Julia Wenger, Sandra Mayr, Ella Bossy-Wetzel, Sandra Puehringer Jan 2012

Purification, Crystallization And X-Ray Diffraction Analysis Of Human Dynamin-Related Protein 1 Gtpase-Ged Fusion Protein, Eva Klinglmayr, Julia Wenger, Sandra Mayr, Ella Bossy-Wetzel, Sandra Puehringer

Faculty Bibliography 2010s

The mechano-enzyme dynamin-related protein 1 plays an important role in mitochondrial fission and is implicated in cell physiology. Dysregulation of Drp1 is associated with abnormal mitochondrial dynamics and neuronal damage. Drp1 shares structural and functional similarities with dynamin 1 with respect to domain organization, ability to self-assemble into spiral-like oligomers and GTP-cycle-dependent membrane scission. Structural studies of human dynamin-1 have greatly improved the understanding of this prototypical member of the dynamin superfamily. However, high-resolution structural information for full-length human Drp1 covering the GTPase domain, the middle domain and the GTPase effector domain (GED) is still lacking. In order to obtain …

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Exposure To Exogenous Enkephalins Disrupts Reproductive Development In The Eastern Lubber Grasshopper, Romalea Microptera (Insecta: Orthoptera), Sandeep Kumar, Purnachandra Nagaraju Ganji, Hojun Song, Laurence Von Kalm, David W. Borst Jan 2012

Exposure To Exogenous Enkephalins Disrupts Reproductive Development In The Eastern Lubber Grasshopper, Romalea Microptera (Insecta: Orthoptera), Sandeep Kumar, Purnachandra Nagaraju Ganji, Hojun Song, Laurence Von Kalm, David W. Borst

Faculty Bibliography 2010s

Enkephalins play a major role in reproductive physiology in crustaceans; however their role in reproductive development in insects is largely unknown. We investigated the effect of exposure to exogenous leucine-enkephalin (Leu-Enk), methionine-enkephalin (Met-Enk), and the opioid antagonist naloxone on gonad development in the Eastern lubber grasshopper, Romalea microptera. Injection of either Leu-Enk or naloxone alone significantly increased the testicular index and testicular follicular diameter in males, and the ovarian index, oocyte length, and oocyte diameter in females. In contrast, injection of Met-Enk inhibited all measures of reproductive development in both sexes. Surprisingly, co-injection of naloxone with either enkephalin enhanced the …

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Phylogenetic Relationships Among Staphylococcus Species And Refinement Of Cluster Groups Based On Multilocus Data, Ryan P. Lamers, Gowrishankar Muthukrishnan, Todd A. Castoe, Sergio Tafur, Alexander M. Cole, Christopher L. Parkinson Jan 2012

Phylogenetic Relationships Among Staphylococcus Species And Refinement Of Cluster Groups Based On Multilocus Data, Ryan P. Lamers, Gowrishankar Muthukrishnan, Todd A. Castoe, Sergio Tafur, Alexander M. Cole, Christopher L. Parkinson

Faculty Bibliography 2010s

Background: Estimates of relationships among Staphylococcus species have been hampered by poor and inconsistent resolution of phylogenies based largely on single gene analyses incorporating only a limited taxon sample. As such, the evolutionary relationships and hierarchical classification schemes among species have not been confidently established. Here, we address these points through analyses of DNA sequence data from multiple loci (16S rRNA gene, dnaJ, rpoB, and tuf gene fragments) using multiple Bayesian and maximum likelihood phylogenetic approaches that incorporate nearly all recognized Staphylococcus taxa. Results: We estimated the phylogeny of fifty-seven Staphylococcus taxa using partitioned-model Bayesian and maximum likelihood analysis, as …

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Gadd45 Alpha Inhibition Of Dnmt1 Dependent Dna Methylation During Homology Directed Dna Repair, Bongyong Lee, Annalisa Morano, Antonio Porecellini, Mark T. Muller Jan 2012

Gadd45 Alpha Inhibition Of Dnmt1 Dependent Dna Methylation During Homology Directed Dna Repair, Bongyong Lee, Annalisa Morano, Antonio Porecellini, Mark T. Muller

Faculty Bibliography 2010s

In this work, we examine regulation of DNA methyltransferase 1 (DNMT1) by the DNA damage inducible protein, GADD45 alpha. We used a system to induce homologous recombination (HR) at a unique double-strand DNA break in a GFP reporter in mammalian cells. After HR, the repaired DNA is hypermethylated in recombinant clones showing low GFP expression (HR-L expressor class), while in high expressor recombinants (HR-H clones) previous methylation patterns are erased. GADD45 alpha, which is transiently induced by double-strand breaks, binds to chromatin undergoing HR repair. Ectopic overexpression of GADD45 alpha during repair increases the HR-H fraction of cells (hypomethylated repaired …

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Theta-Defensins: Cyclic Peptides With Endless Potential, Robert I. Lehrer, Alex M. Cole, Michael E. Selsted Jan 2012

Theta-Defensins: Cyclic Peptides With Endless Potential, Robert I. Lehrer, Alex M. Cole, Michael E. Selsted

Faculty Bibliography 2010s

theta-Defensins, the only cyclic peptides of animal origin, have been isolated from the leukocytes of rhesus macaques and baboons. Their biogenesis is unusual because each peptide is an 18-residue chimera formed by the head-to-tail splicing of nonapeptides derived from two separate precursors. theta-Defensins have multiple arginines and a ladder-like tridisulfide array spanning their two antiparallel beta-strands. Human theta-defensin genes contain a premature stop codon that prevents effective translation of the needed precursors; consequently, these peptides are not present in human leukocytes. Synthetic theta-defensins with sequences that correspond to those encoded within the human pseudogenes are called retrocyclins. Retrocyclin-1 inhibits the …

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Hiv-Neutralizing Activity Of Cationic Polypeptides In Cervicovaginal Secretions Of Women In Hiv-Serodiscordant Relationships, Pauline Levinson, Robert Y. Choi, Amy L. Cole, Taha Hirbod, Samuel Rhedin, Barbara Payne, Brandon L. Guthrie, Rose Bosire, Alexander M. Cole, Carey Farquhar, Kristina Broliden Jan 2012

Hiv-Neutralizing Activity Of Cationic Polypeptides In Cervicovaginal Secretions Of Women In Hiv-Serodiscordant Relationships, Pauline Levinson, Robert Y. Choi, Amy L. Cole, Taha Hirbod, Samuel Rhedin, Barbara Payne, Brandon L. Guthrie, Rose Bosire, Alexander M. Cole, Carey Farquhar, Kristina Broliden

Faculty Bibliography 2010s

Background: HIV exposed seronegative (HESN) women represent the population most in need of a prophylactic antiviral strategy. Mucosal cationic polypeptides can potentially be regulated for this purpose and we here aimed to determine their endogenous expression and HIV neutralizing activity in genital secretions of women at risk of HIV infection. Methodology/Principal Findings: Cervicovaginal secretions (CVS) of Kenyan women in HIV-serodiscordant relationships (HESN, n = 164; HIV seropositive, n = 60) and low-risk controls (n = 72) were assessed for the cationic polypeptides HNP1-3, LL-37 and SLPI by ELISA and for HIV neutralizing activity by a PBMC-based assay using an HIV …

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Predicting Folding Pathways Between Rna Conformational Structures Guided By Rna Stacks, Yuan Li, Shaojie Zhang Jan 2012

Predicting Folding Pathways Between Rna Conformational Structures Guided By Rna Stacks, Yuan Li, Shaojie Zhang

Faculty Bibliography 2010s

Background: Accurately predicting low energy barrier folding pathways between conformational secondary structures of an RNA molecule can provide valuable information for understanding its catalytic and regulatory functions. Most existing heuristic algorithms guide the construction of folding pathways by free energies of intermediate structures in the next move during the folding. However due to the size and ruggedness of RNA energy landscape, energy-guided search can become trapped in local optima. Results: In this paper, we propose an algorithm that guides the construction of folding pathways through the formation and destruction of RNA stacks. Guiding the construction of folding pathways by coarse …

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Transforming Online Learning Through Narrative And Student Agency, Robb Lindgren, Rudy Mcdaniel Jan 2012

Transforming Online Learning Through Narrative And Student Agency, Robb Lindgren, Rudy Mcdaniel

Faculty Bibliography 2010s

Efforts to improve online learning have focused primarily on the technology platform for delivering educational content and supporting student discourse. In this paper we describe an alternative approach that invokes two powerful forces behind human learning: narrative and agency. Each of these constructs and their potential impacts on learning is reviewed, and the design of a large-enrollment online undergraduate course that leverages these elements is described. A study of student learning and engagement was conducted using surveys and an analysis of student projects on 96 students enrolled in the new course. Surveys were also administered to 129 students taking a …

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Degradation Of Dc Characteristics Of Inaln/Gan High Electron Mobility Transistors By 5 Mev Proton Irradiation, Chien-Fong Lo, L. Liu, T. S. Kang, Fan Ren, C. Schwarz, E. Flitsiyan, L. Chernyak, Hong-Yeol Kim, Jihyun Kim, Sang Pil Yun, O. Laboutin, Y. Cao, J. W. Johnson, S. J. Pearton Jan 2012

Degradation Of Dc Characteristics Of Inaln/Gan High Electron Mobility Transistors By 5 Mev Proton Irradiation, Chien-Fong Lo, L. Liu, T. S. Kang, Fan Ren, C. Schwarz, E. Flitsiyan, L. Chernyak, Hong-Yeol Kim, Jihyun Kim, Sang Pil Yun, O. Laboutin, Y. Cao, J. W. Johnson, S. J. Pearton

Faculty Bibliography 2010s

The dc characteristics of InAlN/GaN high electron mobility transistors were measured before and after irradiation with 5 MeV protons at doses up to 2 x 10(15) cm(-2). The on/off ratio degraded by two orders of magnitude for the highest dose, while the subthreshold slope increased from 77 to 122 mV/decade under these conditions. There was little change in transconductance or gate or drain currents for doses up to 2 x 10(13) cm(-2), but for the highest dose the drain current and transconductance decreased by, similar to 40% while the reverse gate current increased by a factor of similar to 6. …

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A Novel Role Of Kruppel-Like Factor 8 In Dna Repair In Breast Cancer Cells, Heng Lu, Liu Hu, Tianshu Li, Satadru Lahiri, Chao Shen, Melissa S. Wason, Debarati Mukherjee, Hui Xie, Lin Yu, Jihe Zao Jan 2012

A Novel Role Of Kruppel-Like Factor 8 In Dna Repair In Breast Cancer Cells, Heng Lu, Liu Hu, Tianshu Li, Satadru Lahiri, Chao Shen, Melissa S. Wason, Debarati Mukherjee, Hui Xie, Lin Yu, Jihe Zao

Faculty Bibliography 2010s

Kruppel-like factor 8 (KLF8) regulates critical gene transcription and cellular events associated with cancer. However, the role of KLF8 in cancer remains largely unknown. Here, we report a surprisingly novel role for KLF8 inDNArepair in breast cancer cells. Comet, clonogenic, and WST-1 assays showed that KLF8 expression is required for protecting human breast cancer cells from doxorubicin-induced DNA damage and cell death. Western blotting indicated that overexpression of ectopic KLF8 attenuated the levels of the DNA damage marker gamma H2A.X in doxorubicin-treated PARP-1(+/+) but not PARP-1(-/-) mouse embryonic fibroblasts, whereas the PARP-1-binding-defective KLF8 mutant failed to do so. Interestingly, in …

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Pump-To-Stokes Relative Intensity Noise Transfer And Analytical Modeling Of Mid-Infrared Silicon Raman Lasers, J. Ma, S. Fathpour Jan 2012

Pump-To-Stokes Relative Intensity Noise Transfer And Analytical Modeling Of Mid-Infrared Silicon Raman Lasers, J. Ma, S. Fathpour

Faculty Bibliography 2010s

An analytical model for mid-infrared (mid-IR) silicon Raman lasers (SRLs) is developed. The relative intensity noise (RIN) transfer from the pump to the Stokes in the lasers is also investigated. The analytical model can be used as a versatile and efficient tool for analysis, design and optimization of mid-IR SRLs. It is shown that conversion efficiency of 70% is attainable and the low-frequency RIN transfer may be suppressed to below 1 dB by pumping low-loss waveguides at high intensities.

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Mitochondrial Dynamics And Bioenergetic Dysfunction Is Associated With Synaptic Alterations In Mutant Sod1 Motor Neurons, Jordi Magrané, Mary Anne Sahawneh, Serge Przedborski, Álvaro G. Estévez, Giovanni Manfredi Jan 2012

Mitochondrial Dynamics And Bioenergetic Dysfunction Is Associated With Synaptic Alterations In Mutant Sod1 Motor Neurons, Jordi Magrané, Mary Anne Sahawneh, Serge Przedborski, Álvaro G. Estévez, Giovanni Manfredi

Faculty Bibliography 2010s

Mutations in Cu,Zn superoxide dismutase (SOD1) cause familial amyotrophic lateral sclerosis (FALS), a rapidly fatal motor neuron disease. Mutant SOD1 has pleiotropic toxic effects on motor neurons, among which mitochondrial dysfunction has been proposed as one of the contributing factors in motor neuron demise. Mitochondria are highly dynamic in neurons; they are constantly reshaped by fusion and move along neurites to localize at sites of high-energy utilization, such as synapses. The finding of abnormal mitochondria accumulation in neuromuscular junctions, where the SOD1-FALS degenerative process is though to initiate, suggests that impaired mitochondrial dynamics in motor neurons may be involved in …

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The Effect Of A Dietary Supplement (N-Oleyl-Phosphatidyl-Ethanolamine And Epigallocatechin Gallate) On Dietary Compliance And Body Fat Loss In Adults Who Are Overweight: A Double-Blind, Randomized Control Trial, Gerald T. Mangine, Adam M. Gonzalez, Adam J. Wells, William P. Mccormack, Maren S. Fragala, Jeffrey R. Stout, Jay R. Hoffman Jan 2012

The Effect Of A Dietary Supplement (N-Oleyl-Phosphatidyl-Ethanolamine And Epigallocatechin Gallate) On Dietary Compliance And Body Fat Loss In Adults Who Are Overweight: A Double-Blind, Randomized Control Trial, Gerald T. Mangine, Adam M. Gonzalez, Adam J. Wells, William P. Mccormack, Maren S. Fragala, Jeffrey R. Stout, Jay R. Hoffman

Faculty Bibliography 2010s

Background: A dietary supplement containing a blend of 170 mg of N-oleyl-phosphatidylethanolamine (NOPE) and 100 mg of epigallocatechin-3-gallate (EGCG) has been shown to improve compliance to low caloric diets. Considering the cost of dietary ingredients, many manufacturers attempt to determine the lowest efficacious dose. Thus, the purpose of this study was to evaluate the efficacy of 8-weeks of supplementation with a daily intake of 120 mg of NOPE and 105 mg of EGCG in conjunction with a low caloric diet and regular, moderate exercise on dietary compliance in healthy, overweight adults. An additional purpose was to examine the effect of …

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Metabolic Effects Of Intra-Abdominal Fat In Ghrko Mice, Michal M. Masternak, Andrzej Bartke, Feiya Wang, Adam Spong, Adam Gesing, Yimin Fang, Adam B. Salmon, Larry F. Hughes, Teresa Liberati, Ravneet Boparai, John J. Kopchick, Reyhan Westbrook Jan 2012

Metabolic Effects Of Intra-Abdominal Fat In Ghrko Mice, Michal M. Masternak, Andrzej Bartke, Feiya Wang, Adam Spong, Adam Gesing, Yimin Fang, Adam B. Salmon, Larry F. Hughes, Teresa Liberati, Ravneet Boparai, John J. Kopchick, Reyhan Westbrook

Faculty Bibliography 2010s

Mice with targeted deletion of the growth hormone receptor (GHRKO mice) are growth hormone (GH) resistant, small, obese, hypoinsulinemic, highly insulin sensitive and remarkably long-lived. To elucidate the unexpected coexistence of adiposity with improved insulin sensitivity and extended longevity, we examined effects of surgical removal of visceral (epididymal and perinephric) fat on metabolic traits related to insulin signaling and longevity. Comparison of results obtained in GHRKO mice and in normal animals from the same strain revealed disparate effects of visceral fat removal (VFR) on insulin and glucose tolerance, adiponectin levels, accumulation of ectopic fat, phosphorylation of insulin signaling intermediates, body …

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Loss Of Ccdc6, The First Identified Ret Partner Gene, Affects Ph2ax S139 Levels And Accelerates Mitotic Entry Upon Dna Damage, Francesco Merolla, Chiara Luise, Mark T. Muller, Roberto Pacelli, Alfredo Fusco, Angela Celetti Jan 2012

Loss Of Ccdc6, The First Identified Ret Partner Gene, Affects Ph2ax S139 Levels And Accelerates Mitotic Entry Upon Dna Damage, Francesco Merolla, Chiara Luise, Mark T. Muller, Roberto Pacelli, Alfredo Fusco, Angela Celetti

Faculty Bibliography 2010s

CCDC6 was originally identified in chimeric genes caused by chromosomal translocation involving the RET proto-oncogene in some thryoid tumors mostly upon ionizing radiation exposure. Recognised as a pro-apoptotic phosphoprotein that negatively regulates CREB1-dependent transcription, CCDC6 is an ATM substrate that is responsive to genotoxic stress. Here we report that following genotoxic stress, loss or inactivation of CCDC6 in cancers that carry the CCDC6 fusion, accelerates the dephosphorylation of pH2AX S139, resulting in defective G2 arrest and premature mitotic entry. Moreover, we show that CCDC6 depleted cells appear to repair DNA damaged in a shorter time compared to controls, based on …

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Role Of Atg16l, Nod2 And Il23r In Crohn's Disease Pathogenesis, Saleh A. Naser, Melissa Arce, Anam Khaja, Marlene Fernandez, Najih Naser, Sammer Elwasila, Saisathya Thanigachalam Jan 2012

Role Of Atg16l, Nod2 And Il23r In Crohn's Disease Pathogenesis, Saleh A. Naser, Melissa Arce, Anam Khaja, Marlene Fernandez, Najih Naser, Sammer Elwasila, Saisathya Thanigachalam

Faculty Bibliography 2010s

Inflammatory bowel disease is a group of diseases that includes Crohn's disease (CD) and ulcerative colitis. CD is characterized as a chronic inflammatory disease of the gastrointestinal tract, ranging from the mouth to the anus. Although there are gross pathological and histological similarities between CD and Johne's disease of cattle, the cause of CD remains controversial. It is vital to understand fully the cause of this disease because it affects approximately 500 000 people in North America and Europe. It ranges from 27 to 48 cases per 100 000 people. There are many theories on the cause of CD ranging …

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Complete Chloroplast Genome Sequence Of An Orchid Model Plant Candidate: Erycina Pusilla Apply In Tropical Oncidium Breeding, I-Chun Pan, Der-Chih Liao, Fu-Huei Wu, Henry Daniell, Nameirakpam Dolendro Singh, Chen Chang, Ming-Che Shih, Ming-Tsair Chan, Choun-Sea Lin Jan 2012

Complete Chloroplast Genome Sequence Of An Orchid Model Plant Candidate: Erycina Pusilla Apply In Tropical Oncidium Breeding, I-Chun Pan, Der-Chih Liao, Fu-Huei Wu, Henry Daniell, Nameirakpam Dolendro Singh, Chen Chang, Ming-Che Shih, Ming-Tsair Chan, Choun-Sea Lin

Faculty Bibliography 2010s

Oncidium is an important ornamental plant but the study of its functional genomics is difficult. Erycina pusilla is a fast-growing Oncidiinae species. Several characteristics including low chromosome number, small genome size, short growth period, and its ability to complete its life cycle in vitro make E. pusilla a good model candidate and parent for hybridization for orchids. Although genetic information remains limited, systematic molecular analysis of its chloroplast genome might provide useful genetic information. By combining bacterial artificial chromosome (BAC) clones and next-generation sequencing (NGS), the chloroplast (cp) genome of E. pusilla was sequenced accurately, efficiently and economically. The cp …

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Probing Grain Boundaries In Ceramic Scintillators Using X-Ray Radioluminescence Microscopy, Stephen R. Podowitz, Romain M. Gaumé, Robert S. Feigelson Jan 2012

Probing Grain Boundaries In Ceramic Scintillators Using X-Ray Radioluminescence Microscopy, Stephen R. Podowitz, Romain M. Gaumé, Robert S. Feigelson

Faculty Bibliography 2010s

X-ray radioluminescence microscopy (XRLM), a novel fluorescence microscopy technique under focused x-ray excitation, was used to characterize micro-scale luminescence of Eu:Y2O3 and Ce:YAG transparent ceramics and bicrystals. The diffusion length of a known semiconductor measured by XRLM was found to be in agreement with previously measured values, illustrating its use for characterizing charge carrier transport. Emission intensity was found to drop at the boundaries in both Eu:Y2O3 and Ce:YAG ceramics and bicrystals. The depletion in emission at grain boundaries was ultimately found to be related to charge carrier depletion (through either deep trapping or non-radiative recombination). A charge carrier diffusion …

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Lipid Rafts Alter The Stability And Activity Of The Cholera Toxin A1 Subunit, Supriyo Ray, Michael Taylor, Tuhina Banerjee, Suren A. Tatulian, Ken Teter Jan 2012

Lipid Rafts Alter The Stability And Activity Of The Cholera Toxin A1 Subunit, Supriyo Ray, Michael Taylor, Tuhina Banerjee, Suren A. Tatulian, Ken Teter

Faculty Bibliography 2010s

Cholera toxin (CT) travels from the cell surface to the endoplasmic reticulum (ER) as an AB holotoxin. ER-specific conditions then promote the dissociation of the catalytic CTA1 subunit from the rest of the toxin. CTA1 is held in a stable conformation by its assembly in the CT holotoxin, but the dissociated CTA1 subunit is an unstable protein that spontaneously assumes a disordered state at physiological temperature. This unfolding event triggers the ER-to-cytosol translocation of CTA1 through the quality control mechanism of ER-associated degradation. The translocated pool of CTA1 must regain a folded, active structure to modify its G protein target …

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An Enhanced Hypercube-Based Encoding For Evolving The Placement, Density, And Connectivity Of Neurons, Sebastian Risi, Kenneth O. Stanley Jan 2012

An Enhanced Hypercube-Based Encoding For Evolving The Placement, Density, And Connectivity Of Neurons, Sebastian Risi, Kenneth O. Stanley

Faculty Bibliography 2010s

Intelligence in nature is the product of living brains, which are themselves the product of natural evolution. Although researchers in the field of neuroevolution (NE) attempt to recapitulate this process, artificial neural networks (ANNs) so far evolved through NE algorithms do not match the distinctive capabilities of biological brains. The recently introduced hypercube-based neuroevolution of augmenting topologies (HyperNEAT) approach narrowed this gap by demonstrating that the pattern of weights across the connectivity of an ANN can be generated as a function of its geometry, thereby allowing large ANNs to be evolved for high-dimensional problems. Yet the positions and number of …

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A Pseudo-Trna Modulates Antibiotic Resistance In Bacillus Cereus, Theresa E. Rogers, Sandro F. Ataide, Kiley Dare, Assaf Katz, Stephanie Seveau, Hervé Roy, Michael Ibba Jan 2012

A Pseudo-Trna Modulates Antibiotic Resistance In Bacillus Cereus, Theresa E. Rogers, Sandro F. Ataide, Kiley Dare, Assaf Katz, Stephanie Seveau, Hervé Roy, Michael Ibba

Faculty Bibliography 2010s

Bacterial genomic islands are often flanked by tRNA genes, which act as sites for the integration of foreign DNA into the host chromosome. For example, Bacillus cereus ATCC14579 contains a pathogenicity island flanked by a predicted pseudo-tRNA, tRNA(Other), which does not function in translation. Deletion of tRNA(Other) led to significant changes in cell wall morphology and antibiotic resistance and was accompanied by changes in the expression of numerous genes involved in oxidative stress responses, several of which contain significant complementarities to sequences surrounding tRNA(Other). This suggested that tRNA(Other) might be expressed as part of a larger RNA, and RACE analysis …

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Linking The Transcriptional Profiles And The Physiological States Of Mycobacterium Tuberculosis During An Extended Intracellular Infection, Kyle H. Rohde, Diogo F. T. Veiga, Shannon Caldwell, Gábor Balázsi, David G. Russell Jan 2012

Linking The Transcriptional Profiles And The Physiological States Of Mycobacterium Tuberculosis During An Extended Intracellular Infection, Kyle H. Rohde, Diogo F. T. Veiga, Shannon Caldwell, Gábor Balázsi, David G. Russell

Faculty Bibliography 2010s

Intracellular pathogens such as Mycobacterium tuberculosis have evolved strategies for coping with the pressures encountered inside host cells. The ability to coordinate global gene expression in response to environmental and internal cues is one key to their success. Prolonged survival and replication within macrophages, a key virulence trait of M. tuberculosis, requires dynamic adaptation to diverse and changing conditions within its phagosomal niche. However, the physiological adaptations during the different phases of this infection process remain poorly understood. To address this knowledge gap, we have developed a multi-tiered approach to define the temporal patterns of gene expression in M. tuberculosis …

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Jund/Ap-1-Mediated Gene Expression Promotes Lymphocyte Growth Dependent On Interleukin-7 Signal Transduction, Shannon M. Ruppert, Mounir Chehtane, Ge Zhang, Haiyan Hu, Xiaoman Li, Annette R. Khaled Jan 2012

Jund/Ap-1-Mediated Gene Expression Promotes Lymphocyte Growth Dependent On Interleukin-7 Signal Transduction, Shannon M. Ruppert, Mounir Chehtane, Ge Zhang, Haiyan Hu, Xiaoman Li, Annette R. Khaled

Faculty Bibliography 2010s

Interleukin-7 (IL-7) is an essential cytokine for lymphocyte growth that has the potential for promoting immune reconstitution. This feature makes IL-7 an ideal candidate for therapeutic development. As with other cytokines, signaling through the IL-7 receptor induces the JAK/STAT pathway. However, the broad scope of IL-7 regulatory targets likely necessitates the use of other signaling components whose identities remain poorly defined. To this end, we used an IL-7 dependent T-cell line to examine how expression of the glycolytic enzyme, Hexokinase II (HXKII) was regulated by IL-7 in a STAT5-independent manner. Our studies revealed that IL-7 promoted the activity of JNK …

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Methane From Uv-Irradiated Carbonaceous Chondrites Under Simulated Martian Conditions, Andrew C. Schuerger, John E. Moores, Christian A. Clausen, Nadine G. Barlow, Daniel T. Britt Jan 2012

Methane From Uv-Irradiated Carbonaceous Chondrites Under Simulated Martian Conditions, Andrew C. Schuerger, John E. Moores, Christian A. Clausen, Nadine G. Barlow, Daniel T. Britt

Faculty Bibliography 2010s

A UV photolytic process was studied for the production of methane from carbonaceous chondrites under simulated Martian conditions. Methane evolution rates from carbonaceous chondrites were found to be positively correlated to temperature (-80 to 20 degrees C) and the concentration of carbon in the chondrites (0.2 to 1.69 wt%); and decreased over time with Murchison samples exposed to Martian conditions. The amount of evolved methane (EM) per unit of UV energy was 7.9 x 10(-13) mol J(-1) for UV irradiation of Murchison (1.69 wt%) samples tested under Martian conditions (6.9 mbar and 20 degrees C). Using a previously described Mars …

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Antibacterial Activity Of Polymer Coated Cerium Oxide Nanoparticles, Vishal Shah, Shreya Shah, Hirsh Shah, Fred J. Rispoli, Kevin T. Mcdonnell, Selam Workeneh, Ajay Karakoti, Amit Kumar, Sudipta Seal Jan 2012

Antibacterial Activity Of Polymer Coated Cerium Oxide Nanoparticles, Vishal Shah, Shreya Shah, Hirsh Shah, Fred J. Rispoli, Kevin T. Mcdonnell, Selam Workeneh, Ajay Karakoti, Amit Kumar, Sudipta Seal

Faculty Bibliography 2010s

Cerium oxide nanoparticles have found numerous applications in the biomedical industry due to their strong antioxidant properties. In the current study, we report the influence of nine different physical and chemical parameters: pH, aeration and, concentrations of MgSO4, CaCl2, KCl, natural organic matter, fructose, nanoparticles and Escherichia coli, on the antibacterial activity of dextran coated cerium oxide nanoparticles. A least-squares quadratic regression model was developed to understand the collective influence of the tested parameters on the anti-bacterial activity and subsequently a computer-based, interactive visualization tool was developed. The visualization allows us to elucidate the effect of each of the parameters …

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An Energetically Beneficial Leader-Linker Interaction Abolishes Ligand-Binding Cooperativity In Glycine Riboswitches, Eileen M. Sherman, Jackie Esquiaqui, Galal Elsayed, Jing-Dong Ye Jan 2012

An Energetically Beneficial Leader-Linker Interaction Abolishes Ligand-Binding Cooperativity In Glycine Riboswitches, Eileen M. Sherman, Jackie Esquiaqui, Galal Elsayed, Jing-Dong Ye

Faculty Bibliography 2010s

Comprised of two aptamers connected by a short nucleotide linker, the glycine riboswitch was the first example of naturally occurring RNA elements reported to bind small organic molecules cooperatively. Earlier works have shown binding of glycine to the second aptamer allows tertiary interactions to be made between the two aptamers, which facilitates binding of a separate glycine molecule to the first aptamer, leading to glycine-binding cooperativity. Prompted by a distinctive protection pattern in the linker region of a minimal glycine riboswitch construct, we have identified a highly conserved ( > 90%) leader-linker duplex involving leader nucleotides upstream of the previously reported …

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Embryonic Stem Cells Improve Cardiac Function In Doxorubicin-Induced Cardiomyopathy Mediated Through Multiple Mechanisms, Dinender K. Singla, Aisha Ahmed, Reetu Singla, Binbin Yan Jan 2012

Embryonic Stem Cells Improve Cardiac Function In Doxorubicin-Induced Cardiomyopathy Mediated Through Multiple Mechanisms, Dinender K. Singla, Aisha Ahmed, Reetu Singla, Binbin Yan

Faculty Bibliography 2010s

Doxorubicin (DOX) is an effective anti neoplastic agent used for the treatment of a variety of cancers. Unfortunately, its use is limited as this drug induces cardiotoxicity and heart failure as a side effect. There is no report that describes whether transplanted embryonic stem (ES) cells or their conditioned medium (CM) in DOX-induced cardiomyopathy (DIC) can repair and regenerate myocardium. Therefore, we transplanted ES cells or CM in DIC to examine apoptosis. fibrosis, cytoplasmic vacuolization, and myofibrillar loss and their associated Akt and ERK pathway. Moreover, we also determined activation of endogenous c-kit(+ve) cardiac stem cells (CSCs), levels of FIGF …

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Wax Ester Synthesis Is Required For Mycobacterium Tuberculosis To Enter In Vitro Dormancy, Tatiana D. Sirakova, Chirajyoti Deb, Jaiyanth Daniel, Harminder D. Singh, Hedia Maamar, Vinod S. Dubey, Pappachan E. Kolattukudy Jan 2012

Wax Ester Synthesis Is Required For Mycobacterium Tuberculosis To Enter In Vitro Dormancy, Tatiana D. Sirakova, Chirajyoti Deb, Jaiyanth Daniel, Harminder D. Singh, Hedia Maamar, Vinod S. Dubey, Pappachan E. Kolattukudy

Faculty Bibliography 2010s

Mycobacterium tuberculosis (Mtb) is known to produce wax esters (WE) when subjected to stress. However, nothing is known about the enzymes involved in biosynthesis of WE and their role in mycobacterial dormancy. We report that two putative Mtb fatty acyl-CoA reductase genes (fcr) expressed in E. coli display catalytic reduction of fatty acyl-CoA to fatty aldehyde and fatty alcohol. Both enzymes (FCR1/Rv3391) and FCR2/Rv1543) showed a requirement for NADPH as the reductant, a preference for oleoyl-CoA over saturated fatty acyl-CoA and were inhibited by thiol-directed reagents. We generated Mtb gene-knockout mutants for each reductase. Metabolic incorporation of C-14-oleate into fatty …

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A Package To Study The Performance Of Step-Up And Step-Down Test Procedures, Paul N. Somerville Jan 2012

A Package To Study The Performance Of Step-Up And Step-Down Test Procedures, Paul N. Somerville

Faculty Bibliography 2010s

The package can be used to analyze the performance of step-up and step-down procedures. It can be used to compare powers, calculate the "false discovery rate", to study the effects of reduced step procedures, and to calculate P[U < = k], where U is the number of rejected true hypotheses. It can be used to determine the maximum number of steps that can be made and still guarantee (with a given probability) that the number of false rejections will not exceed some specified number. The test statistics are assumed to have a multivariate-t distribution. Examples are included.

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