bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rabies Virus-Based Vectors Expressing Human Immunodeficiency Virus Type 1 (HIV-1) Envelope Protein Induce a Strong, Cross-Reactive Cytotoxic T-Lymphocyte Response against Envelope Proteins from Different HIV-1 Isolates
Authors: McGettigan James P. , Foley Heather D. , Belyakov Igor M. , Berzofsky Jay A. , Pomerantz Roger J. , Schnell Matthias J. 
Published: July 2002

ABSTRACTNovel viral vectors that are able to induce both strong and long-lasting immune responses may be required as effective vaccines for human immunodeficiency virus type 1 (HIV-1) infection. Our previous experiments with a replication-competent vaccine strain-based rabies virus (RV) expressing HIV-1 envelope protein from a laboratory-adapted HIV-1 strain (NL4–3) and a primary HIV-1 isolate (89.6) showed that RV-based vectors are excellent for B-cell priming. Here we report that cytotoxic T-lymphocyte (CTL) responses against HIV-1 gp160 are induced by recombinant RVs. Our results indicated that a single inoculation of mice with an RV expressing HIV-1 gp160 induced a solid and long-lasting memory CTL response specific for HIV-1 envelope protein. Moreover, CTLs from immunized mice were not restricted to the homologous HIV-1 envelope protein and were able to cross-kill target cells expressing HIV-1 gp160 from heterologous HIV-1 strains. These studies further suggest promise for RV-based vectors to elicit a persistent immune response against HIV-1 and their potential utility as efficacious anti-HIV-1 vaccines.
Interleukin-1α Released from Epithelial Cells after Adenovirus Type 37 Infection Activates Intercellular Adhesion Molecule 1 Expression on Human Vascular Endothelial Cells
Authors: Chang Cheng-Hsien , Huang Yan , Issekutz Andrew C. , Griffith May , Lin Kuei-Hsiang , Anderson Robert 
Published: July 2002

ABSTRACT
A key event in virus-induced inflammation (leukocyte extravasation through the endothelium) is the local activation of endothelial cells, as indicated by the expression of adhesion molecules such as intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin. In order to identify triggers of inflammation in adenovirus infection, we inoculated respiratory and ocular epithelial cells with adenovirus type 37 (Ad37), a human pathogen associated with keratoconjunctivitis as well as urogenital and respiratory infections. Fluids from virus-infected epithelial cells activated ICAM-1 (and to a lesser extent, VCAM-1) expression on cultured human umbilical vein endothelial cells. Blocking studies with anticytokine antibodies implicated interleukin-1α (IL-1α) as the epithelial cell-derived factor which activated endothelial cell ICAM-1 expression. The results thus identify epithelial cell-derived IL-1α as a potentially important activator of endothelial cells in Ad37-induced inflammation.
Envelope-Induced Cell Transformation by Ovine Betaretroviruses
Authors: Alberti Alberto , Murgia Claudio , Liu Shan-Lu , Mura Manuela , Cousens Chris , Sharp Mike , Miller A. Dusty , Palmarini Massimo 
Published: July 2002

ABSTRACT
Ovine betaretroviruses include Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV). JSRV and ENTV represent a unique class of oncogenic retroviruses that induce tumors of the respiratory tract. JSRV and ENTV are highly related but induce different diseases. Expression of the JSRV envelope (Env) induces transformation of rodent fibroblasts in vitro and phosphorylation of Akt, a central player in the phosphatidylinositol 3-kinase (PI-3K)/Akt signal transduction pathway. However, little information is available on the molecular biology of ENTV. In this study, we initially assessed whether the ENTV Env has the same properties as the homologous JSRV protein. We performed entry and interference assays using retroviral vectors pseudotyped with either the JSRV or the ENTV Env and sheep choroid plexus cells, choroid plexus cells stably expressing the JSRV Env protein, human 293T cells, mouse NIH 3T3 cells, or NIH 3T3 cells expressing human hyaluronidase 2 (HYAL2), the cellular receptor for JSRV. The results obtained indicated that ENTV and JSRV share the same receptor in sheep cells and that they can use human HYAL2 as a cellular receptor in mouse cells. The ENTV Env induces transformation of rodent fibroblasts in vitro. As with the JSRV Env, the tyrosine at position 590 is critical for ENTV Env-induced cell transformation, and Akt is phosphorylated in ENTV Env-transformed cells but not in the parental cell lines. Thus, ovine betaretroviruses share a common mechanism of cell transformation. We further investigated the relevance of Akt activation in cells transformed by ovine betaretroviruses. A PI-3K inhibitor blocked Akt phosphorylation in JSRV Env-transformed cells, suggesting a possible involvement of PI-3K in JSRV and ENTV Env-induced cell transformation. In addition, phosphorylated Akt was detected in a cell line derived from a lung tumor of a sheep with naturally occurring ovine pulmonary adenocarcinoma.
Alpha/Beta and Gamma Interferons Are Induced by Infection with Noncytopathic Bovine Viral Diarrhea Virus In Vivo
Authors: Charleston B. , Brackenbury L. S. , Carr B. V. , Fray M. D. , Hope J. C. , Howard C. J. , Morrison W. I. 
Published: July 2002

ABSTRACT
In contrast to the results of previous in vitro studies, experimental infection of calves with noncytopathic bovine viral diarrhea virus (ncpBVDV) was found to induce strong alpha/beta and gamma interferon responses in gnotobiotic animals. These responses were associated with depressed levels of transforming growth factor β (TGF-β) in serum. The results of this study indicate that the immunosuppression caused by ncpBVDV is not associated with low interferon responses or elevated levels of TGF-β.
Cooperation between the Hemagglutinin of Avian Viruses and the Matrix Protein of Human Influenza A Viruses
Authors: Scholtissek Christoph , Stech Jürgen , Krauss Scott , Webster Robert G. 
Published: July 2002

ABSTRACT
To analyze the compatibility of avian influenza A virus hemagglutinins (HAs) and human influenza A virus matrix (M) proteins M1 and M2, we doubly infected Madin-Darby canine kidney cells with amantadine (1-aminoadamantane hydrochloride)-resistant human viruses and amantadine-sensitive avian strains. By using antisera against the human virus HAs and amantadine, we selected reassortants containing the human virus M gene and the avian virus HA gene. In our system, high virus yields and large, well-defined plaques indicated that the avian HAs and the human M gene products could cooperate effectively; low virus yields and small, turbid plaques indicated that cooperation was poor. The M gene products are among the primary components that determine the species specificities of influenza A viruses. Therefore, our system also indicated whether the avian HA genes effectively reassorted into the genome and replaced the HA gene of the prevailing human influenza A viruses. Most of the avian HAs that we tested efficiently cooperated with the M gene products of the early human A/PR/8/34 (H1N1) virus; however, the avian HAs did not effectively cooperate with the most recently isolated human virus that we tested, A/Nanchang/933/95 (H3N2). Cooperation between the avian HAs and the M proteins of the human A/Singapore/57 (H2N2) virus was moderate. These results suggest that the currently prevailing human influenza A viruses might have lost their ability to undergo antigenic shift and therefore are unable to form new pandemic viruses that contain an avian HA, a finding that is of great interest for pandemic planning.
Complement-Mediated Enhancement of Antibody Function for Neutralization of Pseudotype Virus Containing Hepatitis C Virus E2 Chimeric Glycoprotein
Authors: Meyer Keith , Basu Arnab , Przysiecki Craig T. , Lagging L. Martin , Di Bisceglie Adrian M. , Conley Anthony J. , Ray Ranjit 
Published: July 2002

ABSTRACT
We previously reported a number of features of hepatitis C virus (HCV) chimeric glycoproteins related to pseudotype virus entry into mammalian cells. In this study, pseudotype virus was neutralized by HCV E2 glycoprotein-specific antibodies and infected human sera. Neutralization (50% reduction of pseudotype virus plaque formation) was observed with two human immunoglobulin G1 monoclonal antibodies (MAbs) at concentrations of between 2.5 and 10 μg/ml. A hyperimmune rabbit antiserum to an E2 hypervariable region 1 (HVR1) mimotope also exhibited an HCV E2 pseudotype virus neutralization titer of ∼1/50. An E1 pseudotype virus used as a negative control was not neutralized to a significant level (<1/10) by these MAbs or rabbit antiserum to E2 HVR1. Since HCV probably has a lipid envelope, the role of complement in antibody-mediated virus neutralization was examined. Significant increases in the neutralization titers of the human MAbs (∼60- to 160-fold higher) and rabbit antiserum to HVR1 mimotopes (∼10-fold higher) were observed upon addition of guinea pig complement. Further, these studies suggested that complement activation occured primarily by the classical pathway, since a deficiency in the C4 component led to a significant decrease in the level of virus neutralization. This same decrease was not observed with factor B-deficient complement. We also determined that 9 of 56 HCV-infected patient sera (16%) had detectable pseudotype virus neutralization activity at serum dilutions of between 1/20 and 1/50 and that complement addition enhanced the neutralization activity of some of the HCV-infected human sera. Taken together, these results suggest that during infection, HCV E2 glycoprotein induces a weak neutralizing antibody response, that those antibodies can be measured in vitro by the surrogate pseudotype virus plaque reduction assay, and that neutralization function can be augmented by complement.
SUMO-1 Modification of Human Cytomegalovirus IE1/IE72
Authors: Spengler Mary L. , Kurapatwinski Karen , Black Adrian R. , Azizkhan-Clifford Jane 
Published: July 2002

ABSTRACT

Human cytomegalovirus (HCMV) immediate-early protein IE1/IE72 is involved in undermining many cellular processes including cell cycle regulation, apoptosis, nuclear architecture, and gene expression. The multifunctional nature of IE72 suggests that posttranslational modifications may modulate its activities. IE72 is a phosphoprotein and has intrinsic kinase activity (S. Pajovic, E. L. Wong, A. R. Black, and J. C. Azizkhan, Mol. Cell. Biol. 17:6459-6464, 1997). We now demonstrate that IE72 is covalently conjugated to the small ubiquitin-like modifier (SUMO-1). SUMO-1 is an 11.5-kDa protein that is conjugated to multiple proteins and has been reported to exhibit multiple effects, including modulation of protein stability, subcellular localization, and gene expression. A covalently modified protein migrating at ∼92 kDa, which is stabilized by a SUMO-1 hydrolase inhibitor, is revealed by Western blotting with anti-IE72 of lysates from cells infected with HCMV or cells expressing IE72. SUMO modification of IE72 was confirmed by immunoprecipitation with anti-IE72 and anti-SUMO-1 followed by Western blotting with anti-SUMO-1 and anti-IE72, respectively. Lysine 450 is within a sumoylation consensus site (I,V,L)KXE; changing lysine 450 to arginine by point mutation abolishes SUMO-1 modification of IE72. Inhibition of protein phosphatase 1 and 2A, which increases the phosphorylation of IE72, suppresses the formation of SUMO-1-IE72 conjugates. Both wild-type IE72 and IE72
K450R
localize to nuclear PML oncogenic domains and disrupt them. Studies of protein stability, transactivation, and complementation of IE72-deficient HCMV (CR208) have revealed no significant differences between wild-type IE72 and IE72
K450R
.
Selectable Subgenomic and Genome-Length Dicistronic RNAs Derived from an Infectious Molecular Clone of the HCV-N Strain of Hepatitis C Virus Replicate Efficiently in Cultured Huh7 Cells
Authors: Ikeda Masanori , Yi MinKyung , Li Kui , Lemon Stanley M. 
Published: July 2002

ABSTRACT
Dicistronic, selectable subgenomic replicons derived from the Con1 strain of hepatitis C virus (HCV) are capable of autonomous replication in cultured Huh7 cells (Lohmann et al., Science 285:110-113, 1999). However, adaptive mutations in the NS3, NS5A, and/or NS5B proteins are required for efficient replication of these RNAs and increase by orders of magnitude the numbers of G418-resistant colonies selected following transfection of Huh7 cells. Here, we demonstrate that a subgenomic replicon (NNeo/3-5B) derived from an infectious molecular clone of a second genotype 1b virus, HCV-N (Beard et al., Hepatology 30:316-324, 1999) is also capable of efficient replication in Huh7 cells. G418-resistant cells selected following transfection with NNeo/3-5B RNA contained abundant NS5A antigen and HCV RNA detectable by Northern analysis. Replicon RNA in one of three clonally isolated cell lines contained no mutations in the NS3-NS5B polyprotein, confirming that adaptive mutations are not required for efficient replication in these cells. However, the deletion of a unique 4-amino-acid insertion that is present within the interferon sensitivity-determining region (ISDR) of the NS5A protein in wild-type HCV-N drastically decreased the number of G418-resistant colonies obtained following transfection of Huh7 cells. This effect could be reversed by inclusion of a previously described Con1 cell culture-adaptive mutation (S2005→I), confirming that this natural insertion has a controlling role in determining the replication capacity of wild-type HCV-N RNA in Huh7 cells. Additional selectable, dicistronic RNAs encoding NS2-NS5B, E1-NS5B, or the full-length HCV polyprotein were also capable of replication and gave rise to G418-resistant cell clones following transfection of Huh7 cells. We conclude that RNA derived from this documented infectious molecular clone has a unique capacity for replication in Huh7 cells in the absence of additional cell culture-adaptive mutations.
The M184V Mutation Reduces the Selective Excision of Zidovudine 5′-Monophosphate (AZTMP) by the Reverse Transcriptase of Human Immunodeficiency Virus Type 1
Authors: Boyer Paul L. , Sarafianos Stefan G. , Arnold Edward , Hughes Stephen H. 
Published: July 2002

ABSTRACTThe M184V mutation in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) causes resistance to lamivudine, but it also increases the sensitivity of the virus to zidovudine (3′-azido-3′-deoxythymidine; AZT). This sensitization to AZT is seen both in the presence and the absence of the mutations that confer resistance to AZT. AZT resistance is due to enhanced excision of AZT 5′-monophosphate (AZTMP) from the end of the primer by the RT of the resistant virus. Published data suggest that the excision reaction involves pyrophosphorolysis but that the likely in vivo pyrophosphate donor is not pyrophosphate but ATP. The mutations that lead to AZT resistance enhance ATP binding and, in so doing, enhance pyrophosphorolysis. The excision reaction is specific for AZT because HIV-1 RT, which can form a closed complex with a dideoxy-terminated primer and an incoming deoxynucleoside triphosphate (dNTP), does not form the closed complex with an AZTMP-terminated primer and an incoming dNTP. This means that an AZTMP-terminated primer has better access to the site where it can be excised. The M184V mutation alters the polymerase active site in a fashion that specifically interferes with ATP-mediated excision of AZTMP from the end of the primer strand. The M184V mutation does not affect the incorporation of AZT 5′-triphosphate (AZTTP), either in the presence or the absence of mutations that enhance AZTMP excision. However, in the presence of ATP, the M184V mutation does decrease the ability of HIV-1 RT to carry out AZTMP excision. Based on these results, and on the results of other excision experiments, we present a model to explain how the M184V mutation affects AZTMP excision.
Human T-Lymphotropic Virus Type 1 Oncoprotein Tax Promotes S-Phase Entry but Blocks Mitosis
Authors: Liang Min-Hui , Geisbert Thomas , Yao Yao , Hinrichs Steven H. , Giam Chou-Zen 
Published: July 2002

ABSTRACT

Human T-lymphotropic virus type 1 (HTLV-1) Tax exerts pleiotropic effects on multiple cellular regulatory processes to bring about NF-κB activation, aberrant cell cycle progression, and cell transformation. Here we report that Tax stimulates cellular G
1
/S entry but blocks mitosis. Tax expression in naive cells transduced with a retroviral vector, pBabe-Tax, leads to a significant increase in the number of cells in the S phase, with an accompanying rise in the population of cells with a DNA content of 4N or more. In all cell types tested, including BHK-21, mouse NIH 3T3, and human diploid fibroblast WI-38, Tax causes an uncoupling of DNA synthesis from cell division, resulting in the formation of multinucleated giant cells and cells with decondensed, highly convoluted and lobulated nuclei that are reminiscent of the large lymphocytes with cleaved or cerebriform nuclei seen in HTLV-1-positive individuals. This contrasts with the Tax-transformed cell lines, PX1 (fibroblast) and MT4 (lymphocyte), which produce Tax at high levels, but without the accompanying late-stage cell cycle abnormalities. PX1 and MT4 may have been selected to harbor somatic mutations that allow a bypass of the Tax-induced block in mitosis.
New Insights into the Spring-Loaded Conformational Change of Influenza Virus Hemagglutinin
Authors: Gruenke Jennifer A. , Armstrong R. Todd , Newcomb William W. , Brown Jay C. , White Judith M. 
Published: July 2002

ABSTRACT
Influenza virus hemagglutinin undergoes a conformational change in which a loop-to-helix “spring-loaded” conformational change forms a coiled coil that positions the fusion peptide for interaction with the target bilayer. Previous work has shown that two proline mutations designed to disrupt this change disrupt fusion but did not determine the basis for the fusion defect. In this work, we made six additional mutants with single proline substitutions in the region that undergoes the spring-loaded conformational change and two additional mutants with double proline substitutions in this region. All double mutants were fusion inactive. We analyzed one double mutant, F63P/F70P, as an example. We observed that F63P/F70P undergoes key low-pH-induced conformational changes and binds tightly to target membranes. However, limited proteolysis and electron microscopy observations showed that the mutant forms a coiled coil that is only ∼50% the length of the wild type, suggesting that it is splayed in its N-terminal half. This work further supports the hypothesis that the spring-loaded conformational change is necessary for fusion. Our data also indicate that the spring-loaded conformational change has another role beyond presenting the fusion peptide to the target membrane.
The Oncogenic Protein Kinase Tpl-2/Cot Contributes to Epstein-Barr Virus-Encoded Latent Infection Membrane Protein 1-Induced NF-κB Signaling Downstream of TRAF2
Authors: Eliopoulos Aristides G. , Davies Clare , Blake Sarah S. M. , Murray Paul , Najafipour Sohrab , Tsichlis Philip N. , Young Lawrence S. 
Published: July 2002

ABSTRACT
The Epstein-Barr virus-encoded latent infection membrane protein 1 (LMP1) is a pleiotropic protein, the activities of which include effects on cell transformation and phenotype, growth, and survival. The ability of LMP1 to mediate at least some of these phenomena could be attributed to the activation of the transcription factor NF-κB. LMP1 promotes NF-κB activation through the recruitment of the adapter protein TRAF2 and the formation of a dynamic multiprotein complex that includes the NF-κB kinase, the IκB kinases, and their downstream targets, IκBs and p105. In this study, we have identified the oncogenic kinase Tpl-2/Cot as a novel component of LMP1-induced NF-κB signaling. We show that Tpl-2 is expressed in primary biopsies from patients with nasopharyngeal carcinoma and Hodgkin's disease, where LMP1 is also found. Inducible expression of LMP1 promotes the activation of Tpl-2, and a catalytically inactive Tpl-2 mutant suppresses LMP1-induced NF-κB signaling. In colocalization and coimmunoprecipitation experiments, Tpl-2 and TRAF2 were found to interact with Tpl-2 functioning downstream of TRAF2. Consistent with this observation, catalytically inactive Tpl-2 also blocked CD40-mediated NF-κB activation, which largely depends on TRAF2. The ability of Tpl-2 to influence LMP1-induced NF-κB occurs through modulation of both IκBα and p105 functions. Furthermore, Tpl-2 was found to influence the expression of angiogenic mediators, such as COX-2 in LMP1-transfected cells. These data identify Tpl-2 as a component of LMP1 signaling downstream of TRAF2 and as a modulator of LMP1-mediated effects.
Synthesis and Acid-Catalyzed Hydrolysis of Some 3-(4-Methoxyphenyl)propyl Glucuronates
Authors: Poláková Monika , Joniak Dušan , Ďuriš Miloslav 
Published: July 2002

3-(4-Methoxyphenyl)propyl D-glucuronate, 3-(4-methoxyphenyl)propyl methyl 4-O-methyl-α-Dglucopyranosiduronate, 3-(4-methoxyphenyl)propyl 1,2,3,4-tetra-O-acetyl-α-D-glucopyranuronate and 3-(4-methoxyphenyl)propyl 1,2-(S):3,5-di-O-benzylidene-α-D-glucofuranuronate were prepared as a model substances for the ester lignin-saccharide bonds. Rates of acid-catalyzed hydrolysis of the prepared compounds in 1 M HCl in acetonitrile-water 3 : 1 at 20 °C have been measured by LC-DAD analysis and it showed the low stability of the ester bonds towards acid hydrolysis.
Coupling of Electron Transfer and Bond Dissociation Processes in Dinuclear Complexes with Rhodium and Iridium Reaction Centres Bridged by 2,2'-Bipyrimidine
Authors: Kaim Wolfgang , Reinhardt Ralf , Greulich Stefan , Sieger Monika , Klein Axel , Fiedler Jan 
Published: July 2002

The complexes [{MCl(η5-C5Me5)}2(μ-bpym)](PF6)2, bpym = 2,2'-bipyrimidine and M = Rh or Ir, were obtained as isomerically pure species (M = Ir) or as mixtures of cis/trans isomers (M = Rh). Even though these compounds undergo partial dissociation into the mononuclear bpym- and solvento-complexes in DMF or acetonitrile, cyclic voltammetry and, in part, spectroscopy (NMR, EPR, UV-VIS) could be used to analyze their reduction with up to five electrons. In acetonitrile at room temperature, the dirhodium compound displays two sequential chloride-dissociative two-electron cathodic steps, leading to the very reactive [{Rh(η5-C5Me5)}2(μ-bpym)]. At -15 °C in DMF, the diiridium compound was found to be sufficiently inert towards dissociation; it is then reversibly reduced to an EPR-detectable radical cation [{IrCl(η5-C5Me5)}2(μ-bpym)]•+ before two separated chloride-dissociative steps occur.
Methods of appointment and qualifications of club doctors and physiotherapists in English professional football: some problems and issues
Authors: Waddington I , Roderick M , Naik R 
Published: July 2002

Objective—To examine the methods of appointment, experience, and qualifications of club doctors and physiotherapists in professional football.Methods—Semistructured tape recorded interviews with 12 club doctors, 10 club physiotherapists, and 27 current and former players. A questionnaire was also sent to 90 club doctors; 58 were returned.Results—In almost all clubs, methods of appointment of doctors are informal and reflect poor employment practice: posts are rarely advertised and many doctors are appointed on the basis of personal contacts and without interview. Few club doctors had prior experience or qualifications in sports medicine and very few have a written job description. The club doctor is often not consulted about the appointment of the physiotherapist; physiotherapists are usually appointed informally, often without interview, and often by the manager without involving anyone who is qualified in medicine or physiotherapy. Half of all clubs do not have a qualified (chartered) physiotherapist; such unqualified physiotherapists are in a weak position to resist threats to their clinical autonomy, particularly those arising from managers' attempts to influence clinical decisions.Conclusions—Almost all aspects of the appointment of club doctors and physiotherapists need careful re-examination.