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Articles 32521 - 32550 of 39346

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Wing Shape In House Finches Differs Relative To Migratory Habit In Eastern And Western North America, Jeremy R. Egbert, James R. Belthoff Nov 2003

Wing Shape In House Finches Differs Relative To Migratory Habit In Eastern And Western North America, Jeremy R. Egbert, James R. Belthoff

Biology Faculty Publications and Presentations

We investigated whether wing morphology differed between the sedentary House Finches (Carpodacus mexicanus) of western North America and the introduced population of eastern North America, as the latter has developed migratory behavior since its inception. Wing morphology differed between eastern and western House Finches. Eastern House Finches had shorter proximal primaries and a longer outer primary, perhaps reflecting a thinner and more pointed wing, although no disparity in wing length was detected. Since we interpret these differences in wing shape as modifications for flight capability, we believe that initial evidence for morphological divergence relative to migratory habit between eastern and …

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Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral, Amit Singh, Kwang-Wook Choi Nov 2003

Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral, Amit Singh, Kwang-Wook Choi

Biology Faculty Publications

Dorsoventral (DV) patterning is crucial for eye development in invertebrates and higher animals. DV lineage restriction is the primary event in undifferentiated early eye primordia of Drosophila. InDrosophila eye disc, a dorsal-specific GATA family transcription factor pannier (pnr) controls Iroquois-Complex (Iro-C) genes to establish the dorsal eye fate whereas Lobe (L), which is involved in controlling a Notch ligand Serrate (Ser), is specifically required for ventral growth. However, fate of eye disc cells before the onset of dorsal expression of pnr and Iro-C is not known. We show that L/Ser …

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Convergent Habitat Segregation Of Aedes Aegypti And Aedes Albopictus (Diptera : Culicidae) In Southeastern Brazil And Florida, Marieta A H Braks, Ricardo Lourenco-De-Oliveira, Steven A. Juliano, Nildimar A. Honorio, L Philip Lounibos Nov 2003

Convergent Habitat Segregation Of Aedes Aegypti And Aedes Albopictus (Diptera : Culicidae) In Southeastern Brazil And Florida, Marieta A H Braks, Ricardo Lourenco-De-Oliveira, Steven A. Juliano, Nildimar A. Honorio, L Philip Lounibos

Faculty Publications – Biological Sciences

During the rainy season of 2001, the incidence of the dengue vectors Aedes aegypti and Ae. albopictus was examined in different habitats of two cities (Rio de Janeiro and Nova Iguacu) in Rio de Janeiro State, Brazil, and in two cities (Palm Beach and Boca Raton) in Florida. Oviposition trap collections were performed in urban, suburban, and rural habitats in both areas. Our hypothesis that the abundances and frequencies of occurrence of Ae. aegypti and Ae albopictus are affected in opposite ways by increasing urbanization was only partially supported. City, habitat, and their interaction significantly affected the abundance of both …

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Comprehensive Analysis Of Class I And Class Ii Hla Antigens And Chronic Hepatitis B Virus Infection, Chloe L. Thio, David L. Thomas, Peter Karacki, Xiaojiang Gao, Darlene Marti, Richard A. Kaslow, James J. Goedert, Margaret Hilgartner, Steffanie A. Strathdee, Priya Duggal, Stephen J. O'Brien, Jacquie Astemborski, Mary Carrington Nov 2003

Comprehensive Analysis Of Class I And Class Ii Hla Antigens And Chronic Hepatitis B Virus Infection, Chloe L. Thio, David L. Thomas, Peter Karacki, Xiaojiang Gao, Darlene Marti, Richard A. Kaslow, James J. Goedert, Margaret Hilgartner, Steffanie A. Strathdee, Priya Duggal, Stephen J. O'Brien, Jacquie Astemborski, Mary Carrington

Biology Faculty Articles

Following an acute hepatitis B virus (HBV) infection, clearance or persistence is determined in part by the vigor and breadth of the host immune response. Since the human leukocyte antigen system (HLA) is an integral component of the immune response, we hypothesized that the highly polymorphic HLA genes are key determinants of viral clearance. HLA class I and II genes were molecularly typed in 194 Caucasian individuals with viral persistence and 342 matched controls who had cleared the virus. A single class I allele, A*0301 (odds ratio [OR], 0.47; 95% confidence interval [CI], 0.30 to 0.72; P = 0.0005) was …

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Recovery Of Vegetation Following A Wild Fire On The Margins Of Tidal Flats, Padre Island National Seashore, Texas, Robert I. Lonard, Frank W. Judd, Elizabeth H. Smith Nov 2003

Recovery Of Vegetation Following A Wild Fire On The Margins Of Tidal Flats, Padre Island National Seashore, Texas, Robert I. Lonard, Frank W. Judd, Elizabeth H. Smith

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Recovery of halophytic vegetation on the margin of tidal flats following a wildfire at Padre Island National Seashore, Texas, was studied for 26 months. Species richness, species diversity, species importance, evenness and vegetation abundance were evaluated. Species richness and diversity were restored within 108 days after the fire. Sporobolus virginicus was the dominant species on both burned and non-burned transects. Vegetative cover was slow to recover. It took 19 months for cover of burned areas to equal or exceed cover of non-burned areas. Biomass also was slow to recover and it did not equal biomass of non-burned transects in 26 …

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Skeletal Myosin Heavy Chain Function In Cultured Lung Myofibroblasts, Nancy A. Rice, Leslie A. Leinwand Oct 2003

Skeletal Myosin Heavy Chain Function In Cultured Lung Myofibroblasts, Nancy A. Rice, Leslie A. Leinwand

Biology Faculty Publications

Myofibroblasts are unique contractile cells with both muscle and nonmuscle properties. Typically myofibroblasts are identified by the expression of smooth muscle actin (ASMA); however some myofibroblasts also express sarcomeric proteins. In this study, we show that pulmonary myofibroblasts express three of the eight known sarcomeric myosin heavy chains (MyHCs) (IIa, IId, and embryonic) and that skeletal muscle myosin enzymatic activity is required for pulmonary myofibroblast contractility. Furthermore, inhibition of skeletal myosin activity and myofibroblast contraction results in a decrease in both ASMA and skeletal MyHC promoter activity and ASMA protein expression, suggesting a potential coupling of skeletal myosin activity and …

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The Biology Of Canadian Weeds. 126. Amaranthus Albus L., A. Blitoides S. Watson And A. Blitum L., Mihai Costea, François J. Tardif Oct 2003

The Biology Of Canadian Weeds. 126. Amaranthus Albus L., A. Blitoides S. Watson And A. Blitum L., Mihai Costea, François J. Tardif

Biology Faculty Publications

A review of biological information is provided for three species of the genus Amaranthus: A. albus L., A. blitoides S. Watson and A. blitum L. The last species has been revised taxonomically and a new subspecies for Canada is presented—A. blitum subsp. emarginatus (Moq. ex Uline & Bray) Carretero, Munoz Garmendia & Pedrol. Amaranthus albus and A. blitoides are native to the U.S.A. and introduced to Canada. Both species are annual ruderal and agrestal weeds. During the past 100 yr the two species have spread across most provinces of Canada, but the greatest frequency and abundance have been …

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Complex Co-Substrate Addition Increases Initial Petroleum Degradation Rates During Land Treatment By Altering Bacterial Community Physiology, Christopher W, Kaplan, Brian G. Clement, Alice Hamrick, Robert W. Pease, Carl Flint, Raul J. Cano, Christopher L. Kits Oct 2003

Complex Co-Substrate Addition Increases Initial Petroleum Degradation Rates During Land Treatment By Altering Bacterial Community Physiology, Christopher W, Kaplan, Brian G. Clement, Alice Hamrick, Robert W. Pease, Carl Flint, Raul J. Cano, Christopher L. Kits

Biological Sciences

A pilot-scale land treatment unit (LTU) was constructed at the former Guadalupe oil production field with the purpose of investigating the effect of co-substrate addition on the bacterial community and the resulting rate and extent of total petroleum hydrocarbon (TPH) degradation. The TPH was a weathered mid-cut distillate (C10-C32) excavated from the subsurface and stockpiled before treatment. A control cell (Cell 1) in the LTU was amended with nitrogen and phosphorus while the experimental cell (Cell 2) was amended with additional complex co-substrate—corn steep liquor. During the pilot LTU operation, measurements were taken of TPH, nutrients, moisture, aerobic heterotrophic bacteria …

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Evolution Of Avian Locomotion: Correlates Of Flight Style, Locomotor Modules, Nesting Biology, Body Size, Development, And The Origin Of Flapping Flight, Kenneth P. Dial Oct 2003

Evolution Of Avian Locomotion: Correlates Of Flight Style, Locomotor Modules, Nesting Biology, Body Size, Development, And The Origin Of Flapping Flight, Kenneth P. Dial

Biological Sciences Faculty Publications

No abstract provided.

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Nitric Oxide Mediates Seasonal Muscle Potentiation In Clam Gills, Louis F. Gainey Jr., Michael J. Greenberg Oct 2003

Nitric Oxide Mediates Seasonal Muscle Potentiation In Clam Gills, Louis F. Gainey Jr., Michael J. Greenberg

Faculty Publications

The physiology and timing of gill muscle potentiation were explored in the clam Mercenaria mercenaria. When isolated demibranchs were exposed twice (with an intervening wash) to the same concentration of 5-hydroxytryptamine, the second contraction was larger than the first. This potentiation was seasonal: it was present from November through June, and absent from July through October. Potentiation was not affected by the geographic origin of the clams, nor by their acclimation temperature. Potentiation was inhibited by the nitric oxide synthase (NOS) inhibitor L-NAME and mimicked by the nitric oxide (NO) donor DEANO. During the season of potentiation, immunoreactive NOS appeared …

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Configuration For Micro Ph Sensor, Young-Jin Kim, Young-Chul Lee, Byung-Ki Sohn, Chang-Soo Kim, Jung-Hee Lee Oct 2003

Configuration For Micro Ph Sensor, Young-Jin Kim, Young-Chul Lee, Byung-Ki Sohn, Chang-Soo Kim, Jung-Hee Lee

Electrical and Computer Engineering Faculty Research & Creative Works

A fully integrated pH sensor with a built-in reference electrode is proposed. An iridium oxide microelectrode and a pH-insensitive field-effect transistor are used as a pH sensor and a reference electrode, respectively. The sensitivity of the proposed device matches well with the estimated value to within 0.3 mV/pH deviation.

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Creating A Geographical Information System For Freshwater Crabs And Fishes In Greece, Eugene G. Maurakis, Walter R.T. Witschey, Panos S. Economidis, Dimitra Bobori Oct 2003

Creating A Geographical Information System For Freshwater Crabs And Fishes In Greece, Eugene G. Maurakis, Walter R.T. Witschey, Panos S. Economidis, Dimitra Bobori

Virginia Journal of Science

A geographical information system (GIS) for freshwater crabs and fishes in Greece was created in response to the European Environmental Agency's (EEA) biodiversity initiative for European Union countries. A total of 1931 collections, made with seines, dipnets, and backpack electroshockers in 32 drainages of Greece, yielded 126 species of fishes and crabs in 2,359 data records including species, latitude, longitude, drainage, prefecture, and locality, 731 also include stream order, elevation, gradient, stream width and depth, pH, temperature, and distance to river mouth. Our GIS indicates current distributions of species, species rich and poor areas, anomalous species distributions, areas warranting further …

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The Hyperthermophilic Archaeon Sulfolobus: From Exploration To Exploitation, Stan J.J. Brouns, Thijs J.G. Ettema, Kenneth M. Stedman, Jasper Walther, Hauke Smith, Ambrosius P.L. Snijders, Mark Young, Rolf Bernander, Phillip C. Wright, Betina Siebers, John Van Der Oost Oct 2003

The Hyperthermophilic Archaeon Sulfolobus: From Exploration To Exploitation, Stan J.J. Brouns, Thijs J.G. Ettema, Kenneth M. Stedman, Jasper Walther, Hauke Smith, Ambrosius P.L. Snijders, Mark Young, Rolf Bernander, Phillip C. Wright, Betina Siebers, John Van Der Oost

Biology Faculty Publications and Presentations

In the early 1970s, Sulfolobus was first isolated by Thomas Brock and co-workers from sulfur-rich acidic hot springs in Yellowstone National Park. Sulfolobus became one of the model organisms of Archaea in general, and of Crenarchaea in particular. Many of its unusual physiological characteristics have been investigated, and several of its thermostable enzymes have been studied in considerable detail. For fundamental reasons, and because of its potential for industrial applications, Sulfolobus has been selected for a genome sequence project. The recent completion of the Sulfolobus solfataricus genome has set the stage for a series of postgenome research lines that will …

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Regulation Of Na,K-Atpase By Plms, The Phospholemman-Like Protein From Shark: Molecular Cloning, Expression, Cellular Distribution And Functional Effects Of Plms, Yasser A. Mahmmoud, Gordon Cramb, Arvid B. Maunsbach, Christopher P. Cutler, Lara Meischke, Flemming Cornelius Sep 2003

Regulation Of Na,K-Atpase By Plms, The Phospholemman-Like Protein From Shark: Molecular Cloning, Expression, Cellular Distribution And Functional Effects Of Plms, Yasser A. Mahmmoud, Gordon Cramb, Arvid B. Maunsbach, Christopher P. Cutler, Lara Meischke, Flemming Cornelius

Biology: Faculty Publications

In Na,K-ATPase membrane preparations from shark rectal glands, we have previously identified an FXYD domain-containing protein, phospholemman-like protein from shark, PLMS. This protein was shown to associate and modulate shark Na,K-ATPase activity in vitro. Here we describe the complete coding sequence, expression, and cellular localization of PLMS in the rectal gland of the shark Squalus acanthias. The mature protein contained 74 amino acids, including the N-terminal FXYD motif and a C-terminal protein kinase multisite phosphorylation motif. The sequence is preceded by a 20 amino acid candidate cleavable signal sequence. Immunogold labeling of the Na,K-ATPase …

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Chromosome-Wide Control Of Meiotic Crossing Over In C. Elegans, Kenneth J. Hillers, Anne M. Villeneuve Sep 2003

Chromosome-Wide Control Of Meiotic Crossing Over In C. Elegans, Kenneth J. Hillers, Anne M. Villeneuve

Biological Sciences

A central event in sexual reproduction is the reduction in chromosome number that occurs at the meiosis I division. Most eukaryotes rely on crossing over between homologs, and the resulting chiasmata, to direct meiosis I chromosome segregation, yet make very few crossovers per chromosome pair [1] and [2]. This indicates that meiotic recombination must be tightly regulated to ensure that each chromosome pair enjoys the crossover necessary to ensure correct segregation. Here, we investigate control of meiotic crossing over in Caenorhabditis elegans, which averages only one crossover per chromosome pair per meiosis [3] and [4], by constructing genetic maps …

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Biology Department Publications: 2003, Sam Lindgren Sep 2003

Biology Department Publications: 2003, Sam Lindgren

Biology Department Bibliographies

This document is a noncomprehensive list of publications made by graduate students, post-doctoral researchers, and faculty members in the Biology Department in 2003. It indexes those publications available through major databases, and serves as an archival record of the Department’s robust scholarly contributions.

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Characterization Of Six Polymorphic Microsatellites For The Polychaete Tubeworm Hydroides Elegans And Cross-Species Amplification In The Congener Hydroides Hexagonus, J. B. Pettengill, M. G. Hadfield, M. D. Schug, D. E. Wendt Sep 2003

Characterization Of Six Polymorphic Microsatellites For The Polychaete Tubeworm Hydroides Elegans And Cross-Species Amplification In The Congener Hydroides Hexagonus, J. B. Pettengill, M. G. Hadfield, M. D. Schug, D. E. Wendt

Biological Sciences

We isolated and characterized six polymorphic microsatellite loci for the polychaete tubeworm, Hydroides elegans. Two additional loci were not reliably scorable and estimates of heterozygosity were obtained for the other six. In addition, cross-species amplification was successful for two loci using the congener H. hexagonus. Given that few microsatellite loci are available for polychaetes, these markers will be useful in assessing dispersal and gene flow in H. elegans and probably also other polychaetes.

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Differences In Hyporheic-Zone Microbial Community Structure Along A Heavy-Metal Contamination Gradient, Kevin P. Feris, Philip W. Ramsey, Frazar Chris, Johnnie N. Moore, James E. Gannon, William E. Holben Sep 2003

Differences In Hyporheic-Zone Microbial Community Structure Along A Heavy-Metal Contamination Gradient, Kevin P. Feris, Philip W. Ramsey, Frazar Chris, Johnnie N. Moore, James E. Gannon, William E. Holben

Biological Sciences Faculty Publications

Heavy metals contaminate numerous freshwater streams and rivers worldwide. Previous work by this group demonstrated a relationship between the structure of hyporheic microbial communities and the fluvial deposition of heavy metals along a contamination gradient during the fall season. Seasonal variation has been documented in microbial communities in numerous terrestrial and aquatic environments, including the hyporheic zone. The current study was designed to assess whether relationships between hyporheic microbial community structure and heavy-metal contamination vary seasonally by monitoring community structure along a heavy-metal contamination gradient for more than a year. No relationship between total bacterial abundance and heavy metals was …

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Selective Plating Underestimates Abundance And Shows Differential Recovery Of Bifidobacterial Species From Human Feces, Juha H. A. Apajalahti, Anu Kettunen, Päivi H. Nurminen, Hanna Jatila, William E. Holben Sep 2003

Selective Plating Underestimates Abundance And Shows Differential Recovery Of Bifidobacterial Species From Human Feces, Juha H. A. Apajalahti, Anu Kettunen, Päivi H. Nurminen, Hanna Jatila, William E. Holben

Biological Sciences Faculty Publications

The aim of the present work was to compare the efficacies and levels of selectivity of different culture-dependent and -independent methods for analyzing bifidobacteria in human stool samples. The three different culture media used here significantly differed from each other, particularly with regard to the recovery of Bifidobacterium adolescentis. Bifidobacterium medium failed to recover B. adolescentis; Beerens medium recovered some B. adolescentis organisms (17% of total bifidobacteria), whereas tomato-Eugon medium recovered mainly B. adolescentis organisms (58% of total bifidobacteria). A culture-independent method that combines GC fractionation of bacterial community DNA and 16S rRNA sequencing indicated that B. adolescentis organisms accounted …

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Phenology Of Acacia Berlandieri, A. Minuata, A. Rigidula, A. Schaffneri, And Chloroleuconebano In The Lower Rio Grande Valley Of Texas During A Drought, Melissa R. Eddy, Frank W. Judd Sep 2003

Phenology Of Acacia Berlandieri, A. Minuata, A. Rigidula, A. Schaffneri, And Chloroleuconebano In The Lower Rio Grande Valley Of Texas During A Drought, Melissa R. Eddy, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Flowering and fruiting phenology of Acacia berlandieri, A. minuata, A. rigidula, A. schaffneri, and Chloroleucon ebano were studied at 3 sites in the Lower Rio Grande Valley of Texas from July 1998 through August 1999. Severe drought conditions prevailed for the 6 months preceding this study, and rainfall was 20% lower during the study than the long-term mean. Acacia berlandieri had the longest flowering period (5 months); each of the other 3 Acacia species flowered for 3 months. All of the Acacia species flowered in winter or spring (at relatively low temperatures and increasing photoperiod). Peak flowering occurred in February …

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Monitoring Immediate-Early Gene Expression Through Firefly Luciferase Imaging Of Hrs/J Hairless Mice, Michael E. Geusz, Anne M. Collaco Aug 2003

Monitoring Immediate-Early Gene Expression Through Firefly Luciferase Imaging Of Hrs/J Hairless Mice, Michael E. Geusz, Anne M. Collaco

Biological Sciences Faculty Publications

Background: Gene promoters fused to the firefly luciferase gene (luc) are useful for examining gene regulation in live transgenic mice and they provide unique views of functioning organs. The dynamics of gene expression in cells and tissues expressing luciferase can be observed by imaging this enzyme's bioluminescent oxidation of luciferin. Neural pathways involved in specific behaviors have been identified by localizing expression of immediate-early genes such as c-fos. A transgenic mouse line with luc controlled by the human c-fos promoter (fos::luc) has enabled gene expression imaging in brain slice cultures. To optimize imaging of immediate-early gene expression throughout intact mice, …

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Repairing The Sickle Cell Mutation. Ii. Effect Of Psoralen Linker Length On Specificity Of Formation And Yield Of Third Strand-Directed Photoproducts With The Mutant Target Sequence, Olga Amosova, Steven Broitman, Jacques R. Fresco Aug 2003

Repairing The Sickle Cell Mutation. Ii. Effect Of Psoralen Linker Length On Specificity Of Formation And Yield Of Third Strand-Directed Photoproducts With The Mutant Target Sequence, Olga Amosova, Steven Broitman, Jacques R. Fresco

Biology Faculty Publications

Three identical deoxyoligonucleotide third strands with a 3'-terminal psoralen moiety attached by linkers that differ in length (N=16, 6 and 4 atoms) and structure were examined for their ability to form triplex-directed psoralen photoproducts with both the mutant T residue of the Sickle Cell beta-globin gene and the comparable wild-type sequence in linear duplex targets. Specificity and yield of UVA (365 nm) and visible (419 nm) light-induced photoadducts were studied. The total photoproduct yield varies with the linker and includes both monoadducts and crosslinks at various available pyrimidine sites. The specificity of photoadduct formation at the desired mutant T residue …

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Metabolic Responses Of Shorebird Chicks To Cold Stress: Hysteresis Of Cooling And Warming Phases, Robert Ricklefs, Joseph Williams Aug 2003

Metabolic Responses Of Shorebird Chicks To Cold Stress: Hysteresis Of Cooling And Warming Phases, Robert Ricklefs, Joseph Williams

Biology Department Faculty Works

We developed a protocol for determining the maximum rate of oxygen consumption of shorebird chicks (Scolopacidae and Charadriidae) in response to cold challenge. We first subjected the chicks to gradually decreasing temperatures until their metabolism peaked and began to decrease. We ended the cooling phase of a trial when a chick’s body temperature Tb had declined typically to 32–34°C. After this point, we gradually increased the temperature in the metabolism chamber until normal Tb values and thermoneutral resting metabolism were restored. We refer to this cycle as the down–up (DU) protocol. We estimated instantaneous oxygen consumption (V . O∑) using …

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Epidemiology Of Ustilago Bullata Berk. On Bromus Tectorum L. And Implication For Biological Control, Toupta Boguena Aug 2003

Epidemiology Of Ustilago Bullata Berk. On Bromus Tectorum L. And Implication For Biological Control, Toupta Boguena

Theses and Dissertations

The seedling-infecting pathogen Ustilago bullata Berk. is a naturally occurring biological control agent for cheatgrass (Bromus tectorum L.). The effects of temperature and nutrients on pathogen teliospore germination behavior and the effects of temperature on host seed germination were examined. The effects of temperature on sporidial proliferation, host infection in a temperature-controlled environment and in a field setting for eight populations were investigated. The infection success of Ustilago bullata on Bromus tectorum in cultivated fields as a function of seeding date, inoculation method, inoculum density, supplemental watering, and litter was also investigated. Teliospores germinated faster on potato dextrose agar than …

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Phenotype Management: A New Approach To Habitat Restoration, Jason V. Watters, Sean C. Lema, Gabrielle A. Nevitt Aug 2003

Phenotype Management: A New Approach To Habitat Restoration, Jason V. Watters, Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

The goal of habitat restoration is to provide environmental conditions that promote the maintenance and growth of target populations. But rarely is it considered how the allocation of resources influences the diversity of phenotypes in these populations. Here we present a framework for considering how habitat restoration can shape the development and expression of phenotypes. We call this approach phenotype management as it entails restoring the resources in a habitat to manage phenotypic diversity. Phenotype management is achieved by manipulating the spatial and temporal distribution of resources to alter the degree of competition among individuals. Differences in competition, in turn, …

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A Structural Linkage Between The Dimerization And Encapsidation Signals In Hiv-2 Leader Rna, J. M. Lanchy, J. D. Ivanovitch, J. Stephen Lodmell Aug 2003

A Structural Linkage Between The Dimerization And Encapsidation Signals In Hiv-2 Leader Rna, J. M. Lanchy, J. D. Ivanovitch, J. Stephen Lodmell

Biological Sciences Faculty Publications

The 5' untranslated leader region of retroviral RNAs contains noncoding information that is essential for viral replication, including signals for transcriptional transactivation, splicing, primer binding for reverse transcription, dimerization of the genomic RNA, and encapsidation of the viral RNA into virions. These RNA motifs have considerable structural and functional overlap. in this study, we investigate the conformational dynamics associated with the use and silencing of a sequence in HIV-2 RNA that is involved in genomic RNA dimerization called stem-loop 1 (SL1) and its relationship with a flanking sequence that is known to be important for encapsidation of viral RNAs. We …

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Ribosomal Localization Of Translation Initiation Factor If2, Stefano Marzi, William Knight, Letizia Brandi, Enrico Caserta, Natalia Soboleva, Walter E. Hill, Claudio O. Gualerzi, J. Stephen Lodmell Aug 2003

Ribosomal Localization Of Translation Initiation Factor If2, Stefano Marzi, William Knight, Letizia Brandi, Enrico Caserta, Natalia Soboleva, Walter E. Hill, Claudio O. Gualerzi, J. Stephen Lodmell

Biological Sciences Faculty Publications

Bacterial translation initiation factor IF2 is a GTP-binding protein that catalyzes binding of initiator fMet-tRNA in the ribosomal P site. The topographical localization of IF2 on the ribosomal subunits, a prerequisite for understanding the mechanism of initiation complex formation, has remained elusive. Here, we present a model for the positioning of IF2 in the 70S initiation complex as determined by cleavage of rRNA by the chemical nucleases Cu(II):1,10-orthophenanthroline and Fe(II):EDTA tethered to cysteine residues introduced into IF2. Two specific amino acids in the GII domain of IF2 are in proximity to helices H3, H4, H17, and H18 of 16S rRNA. …

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River Flows And Water Wars: Emerging Science For Environmental Decision Making, N. Leroy Poff, J. David Allan, Margaret A. Palmer, David D. Hart, Brian D. Richter, Angela H. Arthington, Kevin H. Rogers, Judy L. Meyer, Jack Arthur Stanford Aug 2003

River Flows And Water Wars: Emerging Science For Environmental Decision Making, N. Leroy Poff, J. David Allan, Margaret A. Palmer, David D. Hart, Brian D. Richter, Angela H. Arthington, Kevin H. Rogers, Judy L. Meyer, Jack Arthur Stanford

Biological Sciences Faculty Publications

Real and apparent conflicts between ecosystem and human needs for fresh water are contributing to the emergence of an alternative model for conducting river science around the world. The core of this new paradigm emphasizes the need to forge new partnerships between scientists and other stakeholders where shared ecological goals and river visions are developed, and the need for new experimental approaches to advance scientific understanding at the scales relevant to whole-river management. We identify four key elements required to make this model succeed: existing and planned water projects represent opportunities to conduct ecosystem-scale experiments through controlled river flow manipulations; …

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Lipopolysaccharide Induced Septicemia In Chronic Morphine Treated Rats, Frank Ocasio Aug 2003

Lipopolysaccharide Induced Septicemia In Chronic Morphine Treated Rats, Frank Ocasio

Seton Hall University Dissertations and Theses (ETDs)

Opiate-addicts have been known to show increased susceptibility to bacterial infection. Lipopolysaccharide (LPS), which is a cell wall component in gram-negative bacterial, is a potent stimulator of inflammation. We investigated how treatment with morphine alters LPS-induced inflammatory responses in the rat. Chronic morphine exposure alone elevated serum endotoxin levels. Animals treated with morphine and LPS (250 µglkg) developed hypothermia, decreased mean arterial pressure (MAP), increased plasma thrombin anti-thrombin III (TAT) complex, and approximately 67% exhibited progressive intramicrovascular coagulation. Morphine also enhanced LPS­ induced leukocyte endothelial adhesion (LEA), suppressed leukocyte flux and corticosterone production, and elevated interleukin- I�, tumor necrotic factor-a, …

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Receptor Activation Regulates Cortical, But Not Vesicular Localization Of Ndp Kinase, Betty C. Gallagher, Kimberly A.P. Mitchell, Gabor Szabo, Angela De S. Otero Aug 2003

Receptor Activation Regulates Cortical, But Not Vesicular Localization Of Ndp Kinase, Betty C. Gallagher, Kimberly A.P. Mitchell, Gabor Szabo, Angela De S. Otero

Faculty Publications and Presentations

We used immunofluorescence techniques to determine the localization of nucleoside diphosphate (NDP) kinase in NIH-3T3 fibroblasts. We found that cytoplasmic NDP kinase can be separated into two populations according to subcellular localization and response to extracellular stimuli. Specifically, within minutes of stimulation of resting fibroblasts with serum, growth factors or bombesin, a portion of NDP kinase becomes associated with membrane ruffles and lamellipodia. Another pool of NDP kinase accumulates independently of stimulation around intracellular vesicles. Transfection of cells with activated Rac mimics, whereas expression of dominant negative Rac inhibits, the effects of extracellular stimulation on the translocation of NDP kinase …

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