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Microbiology

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1996

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Articles 1 - 30 of 36

Full-Text Articles in Life Sciences

The Bradyrhizobium Japonicum Fega Gene Encodes An Iron-Regulated Outer Membrane Protein With Similarity To Hydroxamate-Type Siderophore Receptors., Kristin Levier, Mary Lou Guerinot Dec 1996

The Bradyrhizobium Japonicum Fega Gene Encodes An Iron-Regulated Outer Membrane Protein With Similarity To Hydroxamate-Type Siderophore Receptors., Kristin Levier, Mary Lou Guerinot

Dartmouth Scholarship

Iron is important in the symbiosis between soybean and its nitrogen-fixing endosymbiont Bradyrhizobium japonicum, yet little is known about rhizobial iron acquisition strategies. Analysis of outer membrane proteins (OMPs) from B. japonicum 61A152 identified three iron-regulated OMPs in the size range of several known receptors for Fe(III)-scavenging siderophores. One of the iron-regulated proteins, FegA, was purified and microsequenced, and a reverse genetics approach was used to clone a fegA-containing DNA fragment. Sequencing of this fragment revealed a single open reading frame of 750 amino acids. A putative N-terminal signal sequence of 14 amino acids which would result in a mature …

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About The Cellular Tropism Of The Gammaherpesvirus Bovine Herpesvirus Type 4, Fernando A. Osorio, J. A. Galeota-Wheeler, D. E. Reed, O. Lopez Dec 1996

About The Cellular Tropism Of The Gammaherpesvirus Bovine Herpesvirus Type 4, Fernando A. Osorio, J. A. Galeota-Wheeler, D. E. Reed, O. Lopez

Nebraska Center for Virology: Faculty Publications

We read with interest the recent report by Egyed et al. (4) about the distribution in tissue, in the natural host, of bovine herpesvirus type 4 (BHV-4), a member of the gammaherpesvirus group. Using PCR, those authors were able to trace BHV-4 (Movar strain) in several tissues of experimentally infected cattle (mostly spleen, lung, trachea, and nasal epithelium tissues) at different times, ranging from 3 to 48 days postinfection. The authors also report consistent detection of BHV-4 DNA in what they consider to be a pure population of lymphocytes obtained from peripheral blood of the BHV-4- infected cattle, and then …

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Effect Of Sediment Particle Size And Temperature On Fecal Bacteria Mortality Rates And The Fecal Coliform/Fecal Streptococci Ratio, J. M. Howell, Mark S. Coyne, P. L. Cornelius Nov 1996

Effect Of Sediment Particle Size And Temperature On Fecal Bacteria Mortality Rates And The Fecal Coliform/Fecal Streptococci Ratio, J. M. Howell, Mark S. Coyne, P. L. Cornelius

Plant and Soil Sciences Faculty Publications

Extended survival of fecal bacteria in sediment can obscure the source and extent of fecal contamination in agricultural settings. The variability in fecal coliform/fecal streptococci (FC/FS) ratios with time and discrepancies between observable fecal sources and measured FC/FS ratios in shallow surface water from agricultural watersheds may be explained by examining FC and FS mortality rates in response to ambient temperature and sediment particle size. We measured FC and FS mortality rates at three different temperatures and in three feces-amended sediments with different particle size in a laboratory study. In controlled conditions, using physiological saline to reduce cell death by …

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Human Herpesvirus Type 8 Dna Sequences In Cell-Free Plasma And Mononuclear Cells Of Kaposi's Sarcoma Patients, William J. Harrington, Omar Bagasra, Carlos E. Sosa, Lisa E. Bobroski, Marianna Baum, Xue Lan Wen, Lisa Cabral, Gerald E. Byrne, Roger J. Pomerantz, Charles Wood Nov 1996

Human Herpesvirus Type 8 Dna Sequences In Cell-Free Plasma And Mononuclear Cells Of Kaposi's Sarcoma Patients, William J. Harrington, Omar Bagasra, Carlos E. Sosa, Lisa E. Bobroski, Marianna Baum, Xue Lan Wen, Lisa Cabral, Gerald E. Byrne, Roger J. Pomerantz, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus (HHV) type 8 bas been detected in both classical and AIDS-related Kaposi's sarcoma, body-cavity lymphomas, and other types of tumors. HHV-8 has also been detected in DNA from peripheral blood mononuclear cells (PBMC) of some Kaposi's sarcoma patients and more readily in B cell fractions derived from panned cell subpopulations. Two patients were followed using several methods: in situ hybridization, solution-based polymerase chain reaction (PCR), and in situ PCR. HHV-8 was intermittently detected in plasma and detection correlated with detection in PBMC. In situ PCR demonstrated HHV-8 sequences in both peripheral blood B lymphocytes and, to a lesser …

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Parotid Gland Lipoma: A Rare Entity, S Muzaffar, N Kayani, S H. Hasan Nov 1996

Parotid Gland Lipoma: A Rare Entity, S Muzaffar, N Kayani, S H. Hasan

Department of Pathology and Laboratory Medicine

No abstract provided.

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Bacillus Thuringiensis Hd-73 Spores Have Surface-Localized Cry1ac Toxin: Physiological And Pathogenic Consequences, Cheng Du, Kenneth Nickerson Oct 1996

Bacillus Thuringiensis Hd-73 Spores Have Surface-Localized Cry1ac Toxin: Physiological And Pathogenic Consequences, Cheng Du, Kenneth Nickerson

Papers in Microbiology

Spores from Cry+ strains of Bacillus thuringiensis bound fluorescein isothiocyanate-labeled antibodies specific for the 65-kDa activated Cry 1Ac toxin, whereas spores from Bacillus cereus and Cry- strains of B. thuringiensis did not. The Cry+ spores could be activated for germination by alkaline conditions (pH 10.3), whereas Cry- spores could not. Once the surrounding exosporia had been removed or permeabilized, Cry+ spores were able to bind the toxin receptor(s) from insect gut brush border membrane vesicle preparations, and their germination rates were increased ca. threefold in the presence of brush border membrane vesicles. A model is …

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Genetic And Phylogenetic Divergence Of Feline Immunodeficiency Virus In The Puma (Puma Concolor), Margaret A. Carpenter, Eric W. Brown, Melanie Culver, Warren E. Johnson, Jill Pecon-Slattery, Dulce Brousset, Stephen J. O'Brien Oct 1996

Genetic And Phylogenetic Divergence Of Feline Immunodeficiency Virus In The Puma (Puma Concolor), Margaret A. Carpenter, Eric W. Brown, Melanie Culver, Warren E. Johnson, Jill Pecon-Slattery, Dulce Brousset, Stephen J. O'Brien

Biology Faculty Articles

Feline immunodeficiency virus (FIV) is a lentivirus which causes an AIDS-like disease in domestic cats (Felis catus). A number of other felid species, including the puma (Puma concolor), carry a virus closely related to domestic cat FIV. Serological testing revealed the presence of antibodies to FIV in 22% of 434 samples from throughout the geographic range of the puma. FIV-Pco pol gene sequences isolated from pumas revealed extensive sequence diversity, greater than has been documented in the domestic cat. The puma sequences formed two highly divergent groups, analogous to the clades which have been defined for …

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A Role For A Rab4-Like Gtpase In Endocytosis And In Regulation Of Contractile Vacuole Structure And Function In Dictyostelium Discoideum, John Bush, Lesly A. Temesvari, Juan Rodriguez-Paris, Greg Buczynski, James Cardelli Oct 1996

A Role For A Rab4-Like Gtpase In Endocytosis And In Regulation Of Contractile Vacuole Structure And Function In Dictyostelium Discoideum, John Bush, Lesly A. Temesvari, Juan Rodriguez-Paris, Greg Buczynski, James Cardelli

Publications

The small Mr Rab4-like GTPase, RabD, localizes to the endosomal pathway and the contractile vacuole membrane system in Dictyostelium discoideum. Stably transformed cell lines overexpressing a dominant negative functioning RabD internalized fluid phase marker at 50% of the rate of wild-type cells. Mutant cells were also slower at recycling internalized fluid. Microscopic and biochemical approaches indicated that the transport of fluid to large postlysosome vacuoles was delayed in mutant cells, resulting in an accumulation in acidic smaller vesicles, probably lysosomes. Also, RabD N121I-expressing cell lines missorted a small but significant percentage of newly synthesized lysosomal alpha-mannosidase precursor polypeptides. However, the …

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Crystal Protein Expression During Vegetative Growth Of Dictyostelium, Kristy K. Taylor, Catherine P. Chia Sep 1996

Crystal Protein Expression During Vegetative Growth Of Dictyostelium, Kristy K. Taylor, Catherine P. Chia

Papers in Microbiology

We are studying interactions between membrane proteins and the cytoskeleton of Dictyostelium discoideum. Detergent (Triton X-100) -insoluble cytoskeletons from vegetative (AX2) amebae are enriched in a 70 kDa Concanavalin A (Con A)-binding protein (gp70). An enriched fraction of gp70 was prepared by Con A affinity chromatography of cytoskeletons from axenically-grown cells. N-terminal amino acid sequence of gel-purified gp70 established its identity to a 69 kDa 'crystal protein' previously characterized by Bomblies, et al. (1990, J. Cell Biol. 110:669 -679). Enzymatic deglycosylation of gp70 resulted in a 65 kDa product that did not bind Con A, verifying the predicted number …

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Activation Of The Human Thymidine Kinase (Tk) Promoter By Simian Virus 40 Large T Antigen Requires Both The T Antigen Prb Family-Binding Domain And Tk Promoter Sequences Resembling E2f-Binding Sites., Michelle M. Anderson, Jun Chen, Charles N. Cole, Susan E. Conrad Sep 1996

Activation Of The Human Thymidine Kinase (Tk) Promoter By Simian Virus 40 Large T Antigen Requires Both The T Antigen Prb Family-Binding Domain And Tk Promoter Sequences Resembling E2f-Binding Sites., Michelle M. Anderson, Jun Chen, Charles N. Cole, Susan E. Conrad

Dartmouth Scholarship

Infection of quiescent cells with the DNA tumor virus simian virus 40 induces expression of the cellular thymidine kinase (TK) gene a minimum of 10- to 20-fold, and this induction depends upon the viral protein large T antigen (T-Ag). To define both human TK promoter elements and T-Ag functional domains required for transcriptional induction, we have established a system in which stable Rat-1 transfectants harboring TK promoter-luciferase hybrid genes are infected with recombinant adenoviruses expressing either wild-type or mutant forms of T-Ag and luciferase expression is measured as an indicator of promoter activity. The results show that (i) a 135-bp …

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In Vivo Detection Of Porcine Reproductive And Respiratory Syndrome Virus Rna By In Situ Hybridization At Different Times Post-Infection, Jung-Hyang Sur, Vicki Cooper, Judith A. Galeota, Richard A. Hesse, Alan R. Doster, Fernando A. Osorio Sep 1996

In Vivo Detection Of Porcine Reproductive And Respiratory Syndrome Virus Rna By In Situ Hybridization At Different Times Post-Infection, Jung-Hyang Sur, Vicki Cooper, Judith A. Galeota, Richard A. Hesse, Alan R. Doster, Fernando A. Osorio

Nebraska Center for Virology: Faculty Publications

We studied the distribution of porcine reproductive and respiratory syndrome virus (PRRSV) RNA in tissues by in situ hybridization at different times postinfection (p.i.). The probe used for in situ hybridization was prepared by reverse transcription of PRRSV RNA, followed by PCR amplification of the cDNA. The sequence amplified corresponded to 433 bp from PRRSV open reading frame 7, which is contained in the nucleocapsid protein gene and which is highly conserved in both European and American strains (H. Mardassi, L. Wilson, S. Mounir, and S. Dea, J. Clin. Microbiol. 32:2197–2203, 1994). An immunohistochemical technique was used to detect PRRSV …

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The Bacillus Thuringiensis Insecticidal Toxin Binds Biotin-Containing Proteins, Cheng Du, Kenneth Nickerson Aug 1996

The Bacillus Thuringiensis Insecticidal Toxin Binds Biotin-Containing Proteins, Cheng Du, Kenneth Nickerson

Papers in Microbiology

Brush border membrane vesicles from larvae of the tobacco hornworm, Manduca sexta, contain protein bands of 85 and 120 kDa which react directly with streptavidin conjugated to alkaline phosphatase. The binding could be prevented either by including 10 μM biotin in the reaction mixture or by prior incubation of the brush border membrane vesicles with an activated 60- to 65-kDa toxin from Bacillus thuringiensis HD-73. The ability of B. thuringiensis toxins to recognize biotin-containing proteins was confirmed by their binding to pyruvate carboxylase, a biotin-containing enzyme, as well as to biotinylated ovalbumin and biotinylated bovine serum albumin but not …

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Vif-Negative Human Immunodeficiency Virus Type 1 Persistently Replicates In Primary Macrophages, Producing Attenuated Progeny Virus, Iqbal Chowdhury, Wei Chao, Mary Jane Potash, Pavel Sova, Howard Gendelman, David J. Volsky Aug 1996

Vif-Negative Human Immunodeficiency Virus Type 1 Persistently Replicates In Primary Macrophages, Producing Attenuated Progeny Virus, Iqbal Chowdhury, Wei Chao, Mary Jane Potash, Pavel Sova, Howard Gendelman, David J. Volsky

Nebraska Center for Virology: Faculty Publications

The vif gene of human immunodeficiency virus type 1 (HIV-1) is required for efficient infection of primary T lymphocytes. In this study, we investigated in detail the role of vif in productive infection of primary monocyte-derived macrophages (MDM). Viruses carrying missense or deletion mutations in vif were constructed on the background of the monocytotropic recombinant NLHXADA-GP. Using MDM from multiple donors, we found that vif mutants produced in complementing or partially complementing cell lines were approximately 10% as infectious as wild-type virus when assayed for incomplete, complete, and circularized viral DNA molecules by quantitative PCR amplification or for viral core …

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Resistance Of Blastocystis Hominis Cysts To Chlorine, M Zaki, V Zaman, N A. Sheikh Aug 1996

Resistance Of Blastocystis Hominis Cysts To Chlorine, M Zaki, V Zaman, N A. Sheikh

Department of Pathology and Laboratory Medicine

No abstract provided.

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A Truncated Form Of The Pho80 Cyclin Of Saccharomyces Cerevisiae Induces Expression Of A Small Cytosolic Factor Which Inhibits Vacuole Inheritance., Teresa Nicolson, Barbara Conradt, William Wickner Jul 1996

A Truncated Form Of The Pho80 Cyclin Of Saccharomyces Cerevisiae Induces Expression Of A Small Cytosolic Factor Which Inhibits Vacuole Inheritance., Teresa Nicolson, Barbara Conradt, William Wickner

Dartmouth Scholarship

Vacuoles project streams of vesicles and membranous tubules into the yeast bud where they fuse, founding the daughter cell organelle, vac5-1, which encodes a truncated form of the Pho80 cyclin, inhibits normal vacuole inheritance. An in vitro inheritance assay which measures the fusion of vacuoles serves as a model for several steps of this process. We find that cytosol isolated from the vac5-1 mutant is unable to promote the fusion of wild-type vacuoles in the in vitro assay. Wild-type vacuoles are irreversibly inactivated in a time- and temperature-dependent manner if preincubated with vac5-1 cytosol and ATP, suggesting the presence of …

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Oxidative Stress Detection With Escherichia Coli Harboring A Katg'::Lux Fusion, S. Belkin, D. R. Smulski, Amy Cheng Vollmer, T. K. Van Dyk, R. A. Larossa Jul 1996

Oxidative Stress Detection With Escherichia Coli Harboring A Katg'::Lux Fusion, S. Belkin, D. R. Smulski, Amy Cheng Vollmer, T. K. Van Dyk, R. A. Larossa

Biology Faculty Works

A plasmid containing a transcriptional fusion of the Escherichia coli katG promoter to a truncated Vibrio fischeri lux operon (luxCDABE) was constructed. An E. coli strain bearing this plasmid (strain DPD2511) exhibited low basal levels of luminescence, which increased up to 1,000-fold in the presence of hydrogen peroxide, organic peroxides, redox-cycling agents (methyl viologen and menadione), a hydrogen peroxide-producing enzyme system (xanthine and xanthine oxidase), and cigarette smoke. An oxyR deletion abolished hydrogen peroxide-dependent induction, confirming that oxyR controlled katG'::lux luminescence. Light emission was also induced by ethanol by an unexplained mechanism. A marked synergistic response was observed when cells …

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A Computer-Simulated Restriction Fragment Length Polymorphism Analysis Of Bacterial Small-Subunit Rrna Genes: Efficacy Of Selected Tetrameric Restriction Enzymes For Studies Of Microbial Diversity In Nature, Craig L. Moyer, James M. Tiedje, Fred C. Dobbs, David M. Karl Jul 1996

A Computer-Simulated Restriction Fragment Length Polymorphism Analysis Of Bacterial Small-Subunit Rrna Genes: Efficacy Of Selected Tetrameric Restriction Enzymes For Studies Of Microbial Diversity In Nature, Craig L. Moyer, James M. Tiedje, Fred C. Dobbs, David M. Karl

OES Faculty Publications

An assessment of 10 tetrameric restriction enzymes (TREs) was conducted by using a computer-simulated restriction fragment length polymorphism (RFLP) analysis for over 100 proximally and distally related bacterial small-subunit (SSU) rRNA gene sequences. Screening SSU rDNA clone libraries with TREs has become an effective strategy because of logistic simplicity, commercial availability, and economy. However, the rationale for selecting the type and number of TREs has not been systematically evaluated. Our objective nas to identify the optimal combination of TREs for RnP screening of cloned SSU rRNA genes from undefined bacterial clone libraries. After computer-simulated TRE digestion, the resultant fragments were …

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Subcutaneous Phaeohyphomycosis: Infection With Pigmented Fungi, I N. Soomro, A Kennedy Jul 1996

Subcutaneous Phaeohyphomycosis: Infection With Pigmented Fungi, I N. Soomro, A Kennedy

Department of Pathology and Laboratory Medicine

No abstract provided.

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Molecular Studies On Biv Infection And Its Interaction With Other Bovine Viruses, Charles Wood, Harish Minocha, Yunqi Geng Jun 1996

Molecular Studies On Biv Infection And Its Interaction With Other Bovine Viruses, Charles Wood, Harish Minocha, Yunqi Geng

Nebraska Center for Virology: Faculty Publications

Bovine immunodeficiency virus (BIV) is a bovine lentivirus that infects animals world-wide. The authors have cloned the BIV env and gag proteins and several sub-unit peptides spanning the entire coding regions of the two proteins as fusions to the bacterial trpE protein and expressed them in Escherichia coli (Spindler et al. 1984). These recombinant proteins can readily be expressed but the expression levels of these peptides varied. When these proteins were tested against a panel of bovine sera, only sera from BIV-infected animals reacted specifically. One major antigenic determinant was identified in the cartoxyl terminus of the p26 gag protein …

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Involvement Of The Vacuolar Proton-Translocating Atpase In Multiple Steps Of The Endo-Lysosomal System And In The Contractile Vacuole System Of Dictyostelium Discoideum, Lesly A. Temesvari, Juan M. Rodriguez-Paris, John M. Bush, Linyi Zhang, James A. Cardelli Jun 1996

Involvement Of The Vacuolar Proton-Translocating Atpase In Multiple Steps Of The Endo-Lysosomal System And In The Contractile Vacuole System Of Dictyostelium Discoideum, Lesly A. Temesvari, Juan M. Rodriguez-Paris, John M. Bush, Linyi Zhang, James A. Cardelli

Publications

We have investigated the effects of Concanamycin A (CMA), a specific inhibitor of vacuolar type H(+)-ATPases, on acidification and function of the endo-lysosomal and contractile vacuole (CV) systems of D. discoideum. This drug inhibited acidification and increased the pH of endo-lysosomal vesicles both in vivo and in vitro in a dose dependent manner. Treatment also inhibited endocytosis and exocytosis of fluid phase, and phagocytosis of latex beads. This report also confirms our previous conclusions (Cardelli et al. (1989) J. Biol. Chem. 264, 3454–3463) that maintenance of acidic pH in lumenal compartments is required for efficient processing and targeting of a …

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Longitudinal Studies Of Viral Sequence, Viral Phenotype, And Immunologic Parameters Of Human Immunodeficiency Virus Type 1 Infection In Perinatally Infected Twins With Discordant Disease Courses, Cecelia Hutto, Yi Zhou, Jun He, Rebeca Geffin, Martin Hill, Walter Scott, Charles Wood Jun 1996

Longitudinal Studies Of Viral Sequence, Viral Phenotype, And Immunologic Parameters Of Human Immunodeficiency Virus Type 1 Infection In Perinatally Infected Twins With Discordant Disease Courses, Cecelia Hutto, Yi Zhou, Jun He, Rebeca Geffin, Martin Hill, Walter Scott, Charles Wood

Nebraska Center for Virology: Faculty Publications

Perinatal human immunodeficiency virus type 1 (HIV-1) infections cause a broad spectrum of clinical disease and are variable in both the age of the patient at onset of serious disease and the progression of the clinical course. Heterozygotic perinatally infected twins with a marked difference in their clinical courses were monitored during the first 2 years of life. Twin B, the second-born twin, developed AIDS by 6 months of age and died at 22 months of age, while twin A remained minimally symptomatic through the first 2 years. Sequential blood specimens were obtained from the twins in order to characterize …

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Tyrosine Kinase-Dependent Release Of An Adenovirus Preterminal Protein Complex From The Nuclear Matrix, Peter C. Angeletti, Jeffrey A. Engler May 1996

Tyrosine Kinase-Dependent Release Of An Adenovirus Preterminal Protein Complex From The Nuclear Matrix, Peter C. Angeletti, Jeffrey A. Engler

Nebraska Center for Virology: Faculty Publications

Adenovirus (Ad) replicative complexes form at discrete sites on the nuclear matrix (NM) through the interaction of Ad preterminal protein (pTP). The NM is a highly salt-resistant fibrillar network which is known to anchor transcription, mRNA splicing, and DNA replication complexes. Incubation of rATP with NM to which pTP was bound caused the release of pTP as a pTP-NM complex with a size of 220 to 230 kDa; incubation with 5’ adenylylimidodiphosphate (rAMP-PNP) showed no significant release, indicating that rATP hydrolysis was required. With NM extracts, it was shown that a pTP-NM complex which was capable of binding Ad origin …

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Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation Apr 1996

Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation

Publications (WR)

Field sampling was carried out between 0830 and 1500 beginning at the confluence of Las Vegas Wash and the Inner Las Vegas Bay. Ten (10) locations were sampled, each in a similar manner. Locations of sampling stations are in line from the Wash-Bay confluence to a point midway between Saddle and Black Islands. In addition, sampling was done at a location midway between Sentinel Island and the base of Fortification Hill, and at the buoy line in front of Hoover Dam. Sampling stations are labeled from LV01, at Wash-Bay confluence, to LV17 at Hoover Dam. A significant data collection point …

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Antibody To The Ligand For Cd40 (Gp39) Inhibits Murine Aids-Associated Splenomegaly, Hypergammaglobulinemia, And Immunodeficiency In Disease-Susceptible C57bl/6 Mice., Kathy A. Green, Karen M. Crassi, Jon D. Laman, Arjan Schoneveld, Rendall R. Strawbridge, Teresa M. Foy, Randolph J. Noelle, William R. Green Apr 1996

Antibody To The Ligand For Cd40 (Gp39) Inhibits Murine Aids-Associated Splenomegaly, Hypergammaglobulinemia, And Immunodeficiency In Disease-Susceptible C57bl/6 Mice., Kathy A. Green, Karen M. Crassi, Jon D. Laman, Arjan Schoneveld, Rendall R. Strawbridge, Teresa M. Foy, Randolph J. Noelle, William R. Green

Dartmouth Scholarship

Infection of genetically susceptible C57BL/6 mice with the LP-BM5 isolate of murine retroviruses cause profound splenomegaly, hypergammaglobulinemia, lymphadenopathy, and an immunodeficiency syndrome which includes the development of terminal B-cell lymphomas. Because many of these and the other manifestations of LP-BM5 virus-induced disease are similar to those seen in AIDS, this syndrome has been named murine AIDS, or MAIDS. Previous reports have shown that the onset of MAIDS depends on the presence of both CD41 T cells and B cells and have suggested that CD41 T-cell-B-cell interactions are important to disease pathogenesis. Here, we assessed the possibility that interactions between CD40 …

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Effects Of Sunlight On Bacteriophage Viability And Structure, Ke Wommack, Rt Hill, Ta Muller, Rr Colwell Apr 1996

Effects Of Sunlight On Bacteriophage Viability And Structure, Ke Wommack, Rt Hill, Ta Muller, Rr Colwell

VIMS Articles

Current estimates of viral abundance in natural waters rely on direct counts of virus-like particles (VLPs), using either transmission or epifluorescence microscopy. Direct counts of VLPs, while useful in studies of viral ecology, do not indicate whether the observed VLPs are capable of infection and/or replication. Rapid decay in bacteriophage viability under environmental conditions has been observed. However, it has not been firmly established whether there is a corresponding degradation of the virus particles, To address this question, viable and direct counts were carried out employing two Chesapeake Bay bacteriophages in experimental microcosms incubated for 56 h at two depths …

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Examination Of The Endosomal And Lysosomal Pathways In Dictyostelium Discoideum Myosin I Mutants, Lesly A. Temesvari, John M. Bush, Michelle D. Peterson, Kristine D. Novak, Margaret A. Titus, James A. Cardelli Mar 1996

Examination Of The Endosomal And Lysosomal Pathways In Dictyostelium Discoideum Myosin I Mutants, Lesly A. Temesvari, John M. Bush, Michelle D. Peterson, Kristine D. Novak, Margaret A. Titus, James A. Cardelli

Publications

The role of myosin Is in endosomal trafficking and the lysosomal system was investigated in a Dictyostelium discoideum myosin I double mutant myoB-/C-, that has been previously shown to exhibit defects in fluid-phase endocytosis during growth in suspension culture (Novak et al., 1995). Various properties of the endosomal pathway in the myoB-/C- double mutant as well as in the myoB- and myoC- single mutants, including intravesicular pH, and intracellular retention time and exocytosis of a fluid phase marker, were found to be indistinguishable from wild-type parental cells. The intimate connection between the contractile vacuole complex and the endocytic pathway in …

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Artificial Selection On Jhe Activity In Gryllus Assimilis: Nature Of Activity Differences Between Lines And Effect On Jh Binding And Metabolism, Anthony J. Zera, Jeffrey Sall, Robert Schwartz Feb 1996

Artificial Selection On Jhe Activity In Gryllus Assimilis: Nature Of Activity Differences Between Lines And Effect On Jh Binding And Metabolism, Anthony J. Zera, Jeffrey Sall, Robert Schwartz

Anthony Zera Publications

Genetic lines of the cricket Gryllus assimilis selected for elevated vs. decreased activity of hemolymph juvenile hormone esterase (JHE) exhibited a 6.8-fold difference in enzyme activity by the seventh generation of selection. This documents that hemolymph JHE activity has the capability for rapid evolutionary change. This is the only insect endocrine trait for which such data are currently available. The difference in hemolymph JHE activity between the lines was due, to an equivalent degree, to variation in whole-cricket enzyme activity and allocation of JHE activity to the hemolymph compartment. No differences in kinetic or thermostability characteristics were observed between JHEs …

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Infection Of Primary Human Fetal Astrocytes By Human Herpesvirus 6, Jun He, Micheline Mccarthy, Yi Zhou, Bala Chandran, Charles Wood Feb 1996

Infection Of Primary Human Fetal Astrocytes By Human Herpesvirus 6, Jun He, Micheline Mccarthy, Yi Zhou, Bala Chandran, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 6 (HHV-6) is a lymphotropic betaherpesvirus which productively infects human CD4+ T cells and monocytes. HHV-6 is the etiologic agent for exanthem subitum (roseola), and it is well-known that central nervous system complications occur frequently during the course of HHV-6-associated disease. In addition, HHV-6 has been associated with encephalitis or encephalopathy. However, very little is known about its tropism for neural cells. There are reports that HHV-6 may infect some glial cell lines, but whether it can infect any primary neural cells is not known. Our studies show that both HHV-6A (GS) and HHV-6B (Z-29) can infect …

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The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson Jan 1996

The Lipooligosaccharides Of Haemophilus Ducreyi Are Highly Sialylated, William Melaugh, A A. Campagnari, B W. Gibson

Chemistry Faculty Publications

The major lipooligosaccharides of the sexually transmitted pathogen Haemophilus ducreyi 35000 have been previously found to terminate in N-acetyllactosamine and sialyl-N-acetyllactosamine, Neu5Ac alpha 2-->3Gal beta 1-->4GlcNAc (W. Melaugh, N. J. Phillips, A. A. Campagnari, M. V. Tullius, and B. W. Gibson, Biochemistry 33: 13070-13078, 1994). In this study, mass spectrometry and composition analyses have shown that the lipooligosaccharides from three other H. ducreyi strains also contain N-acetyllactosamine and are highly sialylated (approximately 30 to 50%), although one African strain was found to contain neither of these structural features.

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Cyanonews (Vol. 12, No. 2, July 1996), Jeff Elhai Jan 1996

Cyanonews (Vol. 12, No. 2, July 1996), Jeff Elhai

CyanoNews

CyanoNews was a newsletter that served the cyanobacteriological community from 1985 to 2003, with content provided by readers (sort of a blog before there were blogs). The newsletter reported new findings from the lab, summaries of recent meetings (often provided by graduate students and post-docs entering the field), positions sought or available, life transitions, a compendium of recent cyanobacteria-related articles, and other items of interest to those who study cyanobacteria.

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