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Full-Text Articles in Life Sciences

Azidothymidine And Interferon-Α Induce Apoptosis In Herpesvirus-Associated Lymphomas, Richard K. Lee, Jian-Ping Cai, Vadim Deyev, Parkash Gill, Lisa Cabral, Charles Wood, Ram Agarwal, Wenle Xia, Lawrence Boise, Eckhard Podack, William Harrington Jr. Nov 1999

Azidothymidine And Interferon-Α Induce Apoptosis In Herpesvirus-Associated Lymphomas, Richard K. Lee, Jian-Ping Cai, Vadim Deyev, Parkash Gill, Lisa Cabral, Charles Wood, Ram Agarwal, Wenle Xia, Lawrence Boise, Eckhard Podack, William Harrington Jr.

Nebraska Center for Virology: Faculty Publications

Lymphoproliferative diseases that occur in immunocompromised patients are frequently associated with herpesviruses. These patients often fare poorly after treatment with conventional chemotherapy. We reported previously that patients with AIDS-related Burkitt’s lymphoma (BL) responded to parenteral azidothymidine (AZT) and IFN-α. We found that EBV-positive lymphoma cells derived from these patients cultured with AZT express CD95 and undergo apoptosis. AZT-mediated apoptosis was caspase dependent and occurred despite Fas receptor blockade. In contrast, EBV-negative lymphomas were resistant to AZT-induced apoptosis, as were EBV-positive lymphomas that expressed high levels of bcl-2. Primary effusion lymphoma (PEL) cell lines infected with human herpesvirus type 8 required …


Lymphotropic Virions Affect Chemokine Receptor-Mediated Neural Signaling And Apoptosis: Implications For Human Immunodeficiency Virus Type 1-Associated Dementia, Jialin Zheng, Anuja Ghorpade, Douglas Niemann, Robin L. Cotter, Michael R. Thylin, Leon Epstein, Jennifer Swartz, Robin B. Shepard, Xiaojuan Liu, Adeline Nukuna, Howard E. Gendelman Oct 1999

Lymphotropic Virions Affect Chemokine Receptor-Mediated Neural Signaling And Apoptosis: Implications For Human Immunodeficiency Virus Type 1-Associated Dementia, Jialin Zheng, Anuja Ghorpade, Douglas Niemann, Robin L. Cotter, Michael R. Thylin, Leon Epstein, Jennifer Swartz, Robin B. Shepard, Xiaojuan Liu, Adeline Nukuna, Howard E. Gendelman

Nebraska Center for Virology: Faculty Publications

Chemokine receptors pivotal for human immunodeficiency virus type 1 (HIV-1) infection in lymphocytes and macrophages (CCR3, CCR5, and CXCR4) are expressed on neural cells (microglia, astrocytes, and/or neurons). It is these cells which are damaged during progressive HIV-1 infection of the central nervous system. We theorize that viral coreceptors could effect neural cell damage during HIV-1-associated dementia (HAD) without simultaneously affecting viral replication. To these ends, we studied the ability of diverse viral strains to affect intracellular signaling and apoptosis of neurons, astrocytes, and monocyte-derived macrophages. Inhibition of cyclic AMP, activation of inositol 1,4,5-trisphosphate, and apoptosis were induced by diverse …


Evolutionary Endocrinology Of Juvenile Hormone Esterase: Functional Relationship With Wing Polymorphism In The Cricket, Gryllus Firmus, Anthony J. Zera, Yuan Huang Aug 1999

Evolutionary Endocrinology Of Juvenile Hormone Esterase: Functional Relationship With Wing Polymorphism In The Cricket, Gryllus Firmus, Anthony J. Zera, Yuan Huang

Anthony Zera Publications

The existence, nature, and physiological consequences of genetic variation for juvenile hormone esterase (JHE) activity was studied in the wing-polymorphic cricket, Gryllus firmus. Hemolymph (blood) JHE activity was sixfold lower in nascent short-winged (SW) females, relative to nascent long-winged (LW) females, during the last juvenile stadium (stage). Morph-associated genetic variation for JHE activity had two causes, variation in loci: (1) regulating whole-organism enzyme activity; and (2) controlling the degree to which JHE is secreted into the blood. Reduced JHE activity in nascent SW-selected individuals was associated with reduced in vivo juvenile hormone catabolism. This suggests that variation in JHE …


The Endocrine Genetics Of Wing Polymorphism In Gryllus: Critique Of Recent Studies And State Of The Art, Anthony J. Zera Aug 1999

The Endocrine Genetics Of Wing Polymorphism In Gryllus: Critique Of Recent Studies And State Of The Art, Anthony J. Zera

Anthony Zera Publications

In a series of papers, the most recent of which was published in Evolution, quantitative-genetic experiments were undertaken on reproductive and physiological correlates of wing polymorphism in the sand cricket, Gryllus firmus (Fairbairn 1994; Fairbairn and Yadlowski 1997; Roff et al. 1997). A goal of these studies was to determine the physiological causes underlying: (1) genetic variation for an ecologically important threshold trait (wing polymorphism); and (2) genetic correlations between wing morph and other reproductive and migratory features, such as fecundity and flight muscle histolysis. These authors concluded that genetic variation for the activity of the endocrine regulator, juvenile hormone …


Broad-Spectrum Protection Against Tombusviruses Elicited By Defective Interfering Rnas In Transgenic Plants, Teresa Rubio, Marise Borja, Herman Scholthof, Paul A. Feldstein, Thomas Jack Morris, Andrew O. Jackson Jun 1999

Broad-Spectrum Protection Against Tombusviruses Elicited By Defective Interfering Rnas In Transgenic Plants, Teresa Rubio, Marise Borja, Herman Scholthof, Paul A. Feldstein, Thomas Jack Morris, Andrew O. Jackson

Nebraska Center for Virology: Faculty Publications

We have designed a DNA cassette to transcribe defective interfering (DI) RNAs of tomato bushy stunt virus (TBSV) and have investigated their potential to protect transgenic Nicotiana benthamiana plants from tombusvirus infections. To produce RNAs with authentic 5’ and 3’ termini identical to those of the native B10 DI RNA, the DI RNA sequences were flanked by ribozymes (RzDI). When RzDI RNAs transcribed in vitro were mixed with parental TBSV transcripts and inoculated into protoplasts or plants, they became amplified, reduced the accumulation of the parental RNA, and mediated attenuation of the lethal syndrome characteristic of TBSV infections. Analysis of …


Multicenter Comparison Of Pcr Assays For Detection Of Human Herpesvirus 8 Dna In Semen, Philip E. Pellett, Thomas J. Spira, Omar Bagasra, Chris Boshoff, Lawrence Corey, Laura De Lellis, Meei-Li Huang, Jung-Chung Lin, Steve Matthews, Paolo Monini, Paola Romessi, Carlos Sosa, Charles Wood, John A. Stewart May 1999

Multicenter Comparison Of Pcr Assays For Detection Of Human Herpesvirus 8 Dna In Semen, Philip E. Pellett, Thomas J. Spira, Omar Bagasra, Chris Boshoff, Lawrence Corey, Laura De Lellis, Meei-Li Huang, Jung-Chung Lin, Steve Matthews, Paolo Monini, Paola Romessi, Carlos Sosa, Charles Wood, John A. Stewart

Nebraska Center for Virology: Faculty Publications

Reported prevalences of human herpesvirus 8 (HHV-8) (Kaposi’s sarcoma-associated herpesvirus) in semen have ranged widely. This is possibly due to differences in assay sensitivity, geographic or population-based differences in the true presence of the virus in semen, and PCR contamination. This study assessed interlaboratory sensitivity and reproducibility in the analysis of blinded experimental panels, each consisting of 48 specimens and being composed of semen specimens from different healthy artificial-insemination donors (n = 30) and human immunodeficiency virus (HIV)-infected patients (n= 7) plus positive (n = 4) and negative (n = 7) controls. The experimental panels analyzed in each laboratory were …


Microbiology Of The Oil Fly, Helaeomyia Petrolei, Dana R. Kadavy, Bradley A. Plantz, Christopher A. Shaw, Jill Myatt, Tyler A. Kokjohn, Kenneth Nickerson Apr 1999

Microbiology Of The Oil Fly, Helaeomyia Petrolei, Dana R. Kadavy, Bradley A. Plantz, Christopher A. Shaw, Jill Myatt, Tyler A. Kokjohn, Kenneth Nickerson

Papers in Microbiology

Helaeomyia petrolei larvae isolated from the asphalt seeps of Rancho La Brea in Los Angeles, Calif., were examined for microbial gut contents. Standard counts on Luria-Bertani, MacConkey, and blood agar plates indicated ca. 2 x 105 heterotrophic bacteria per larva. The culturable bacteria represented 15 to 20% of the total population as determined by acridine orange staining. The gut itself contained large amounts of the oil, had no observable ceca, and maintained a slightly acidic pH of 6.3 to 6.5. Despite the ingestion of large amounts of potentially toxic asphalt by the larvae, their guts sustained the growth of …


Interferon Regulatory Factor 2 Represses The Epstein-Barr Virus BamHi Q Latency Promoter In Type Iii Latency, Luwen Zhang, Joseph S. Pagano Apr 1999

Interferon Regulatory Factor 2 Represses The Epstein-Barr Virus BamHi Q Latency Promoter In Type Iii Latency, Luwen Zhang, Joseph S. Pagano

Nebraska Center for Virology: Faculty Publications

Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA-1) is the essential protein for maintenance of the EBV episome and establishment of latency. The BamHI Q promoter (Qp) is used for the transcription of EBNA-1 mRNA in type I and type II latency, which are EBV infection states exemplified by Burkitt’s lymphoma and nasopharyngeal carcinoma. However, Qp is inactive in type III latency, and other promoters (the BamHI C promoter and/or the BamHI W promoter) are used for EBNA-1. The involvement of interferon regulatory factors (IRFs) in the regulation of Qp is suggested by the presence of an essential interferon-stimulated response element …


Nonspecific Interactions Alter Lipopolysaccharide Patterns And Protein Mobility On Sodium Dodecyl Sulfate Polyacrylamide Gels, Aidong Yuan, R L. Pardy, Catherine P. Chia Mar 1999

Nonspecific Interactions Alter Lipopolysaccharide Patterns And Protein Mobility On Sodium Dodecyl Sulfate Polyacrylamide Gels, Aidong Yuan, R L. Pardy, Catherine P. Chia

Papers in Microbiology

In testing whether bacterial lipopolysaccharide (LPS) was a natural substrate for an esterase from the soil amebae Dictyostelium discoideum, we observed altered banding patterns of the LPS and changed protein mobility on sodium dodecyl sulfate (SDS) polyacrylamide gels after incubation of LPS with the enzyme. The initial interpretation of these results was that the enzyme had removed ester-linked acyl chains from the LPS, leading to a change in its migration on gels. However, esterase inactivated by treatment with either dithiothreitol (DTT), heat, or SDS generated the same mobility shifts. Bovine serum albumin (BSA) also induced the same change in …


Chlorella Virus Pbcv-1 Encodes A Functional Homospermidine Synthase, Annette Kaiser, Michael Vollmert, Dorothea Tholl, Michael V. Graves, James Gurnon, Weimei Xing, Amber D. Lisec, Kenneth Nickerson, James L. Van Etten Jan 1999

Chlorella Virus Pbcv-1 Encodes A Functional Homospermidine Synthase, Annette Kaiser, Michael Vollmert, Dorothea Tholl, Michael V. Graves, James Gurnon, Weimei Xing, Amber D. Lisec, Kenneth Nickerson, James L. Van Etten

Kenneth Nickerson Papers

Sequence analysis of the 330-kb genome of chlorella virus Paramecium bursaria chlorella virus 1 (PBCV-1) revealed an open reading frame, A237R, that encodes a protein with 34% amino acid identity to homospermidine synthase from Rhodopseudomonas viridis. Expression of the a237r gene product in Escherichia coli established that the recombinant enzyme catalyzes the NAD+-dependent formation of homospermidine from two molecules of putrescine. The a237r gene is expressed late in PBCV-1 infection. Both uninfected and PBCV-1-infected chlorella, as well as PBCV-1 virions, contain homospermidine, along with the more common polyamines putrescine, spermidine, and cadaverine. The total number of polyamine …


Characterization Of The Jembrana Disease Virus Tat Gene And The Cis- And Trans-Regulatory Elements In Its Long Terminal Repeats, Hexin Chen, Graham Wilcox, Gde Kertayadnya, Charles Wood Jan 1999

Characterization Of The Jembrana Disease Virus Tat Gene And The Cis- And Trans-Regulatory Elements In Its Long Terminal Repeats, Hexin Chen, Graham Wilcox, Gde Kertayadnya, Charles Wood

Nebraska Center for Virology: Faculty Publications

Jembrana disease virus (JDV) is a newly identified bovine lentivirus that is closely related to the bovine immunodeficiency virus (BIV). JDV contains a tat gene, encoded by two exons, which has potent transactivation activity. Cotransfection of the JDV tat expression plasmid with the JDV promoter chloramphenicol acetyltransferase (CAT) construct pJDV-U3R resulted in a substantial increase in the level of CAT mRNA transcribed from the JDV long terminal repeat (LTR) and a dramatic increase in the CAT protein level. Deletion analysis of the LTR sequences showed that sequences spanning nucleotides 268 to 153, including the TATA box and the predicted first …


Carmoviruses (Tombusviridae), Feng Qu, Thomas Jack Morris Jan 1999

Carmoviruses (Tombusviridae), Feng Qu, Thomas Jack Morris

School of Biological Sciences: Faculty Publications

Carmovirus is one of two officially recognized genera of Tombusviridae. Members of Tombusviridae all have icosahedral virions of about 30 nm in diameter with T = 3 symmetry that consists of 180 coat protein (CP) subunits of about 38- 43 kDa and a single-stranded (ss) RNA genome ranging in size from 4.0 to 4.7 kb. Carmoviruses share recognizable sequence similarity in both the polymerase and structural genes with members of the other genus, Tombusvirus. Sequence comparisons and phylogenetic analysis of these genes support the view that the genera are distinct but closely related. In addition, the genome organization of the …