bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human Cytomegalovirus UL76 Encodes a Novel Virion-Associated Protein That Is Able To Inhibit Viral Replication
Authors: Wang Shang-Kwei , Duh Chang-Yih , Wu Cheng-Wen 
Published: August 2004

ABSTRACTThe human cytomegalovirus (HCMV) UL76 gene encodes a highly conserved herpesvirus protein, pUL76, which is able to modulate gene expression in either activation or repression. In this study, two specific transcripts were found to contain the reading frame of UL76, one a 4.5-kb and the other a 5.5-kb tricistronic mRNA encoding the UL76, UL77, and UL78 open reading frames. Both transcripts were expressed with true late kinetics, as revealed by data showing inhibition of production in the presence of phosphonoformic acid. Immediately after viral infection, pUL76 was found in the nuclear fraction and was detected in cells in the presence of the protein synthesis inhibitor cycloheximide. Subsequent virus particle purification and Western blot analysis revealed that two forms of pUL76 are associated within mature virions. The high-molecular-mass protein (H-pUL76) was verified as originating from a free form of pUL76 by cross-linking with an unknown protein(s). By performing a biochemical fractionation experiment with purified virions, we provide evidence that pUL76 and H-pUL76 are associated with the detergent-soluble (envelope) and -insoluble (tegument/capsid) fractions, respectively. Both results were consistent with the images exhibited by immunoelectron microscopy, which showed that the distribution of gold particles labeled by the anti-pUL76 antibody juxtaposed the compartments of the envelope and the tegument/capsid of the virion. Evidence indicated that expression of pUL76 at the immediate-early phase of the viral replication cycle leads to the inhibition of HCMV production. The viral constituent pUL76, with a dominant-negative effect on replication, may provide a novel mechanism for HCMV's resumption of latency.
Capsid Region Involved in Hepatitis A Virus Binding to Glycophorin A of the Erythrocyte Membrane
Authors: Sánchez Glòria , Aragonès Lluís , Costafreda M. Isabel , Ribes Enric , Bosch Albert , Pintó Rosa M. 
Published: August 2004

ABSTRACT
Hepatitis A virus (HAV) has previously been reported to agglutinate human red blood cells at acidic pHs. Treatment of erythrocytes with different enzymes and chemical reagents indicated that HAV attachment is mediated through an interaction with sialylglycoproteins. HAV hemagglutination could be blocked by incubating the virus with glycophorin A, indicating that this sialylglycoprotein is the erythrocyte receptor. The number of receptors used was estimated to be around 500 per cell. At the same time, HAV-induced hemagglutination could also be blocked by either monoclonal antibody H7C27 or an anti-VP3(102-121) ascitic fluid, indicating that lysine 221 of VP1 and the surrounding VP3 residues lining the capsid pit are involved in HAV binding to erythrocytes.
A Consecutive Priming-Boosting Vaccination of Mice with Simian Immunodeficiency Virus (SIV)gag/polDNA and Recombinant Vaccinia Virus Strain DIs Elicits Effective Anti-SIV Immunity
Authors: Someya Kenji , Xin Ke-Qin , Matsuo Kazuhiro , Okuda Kenji , Yamamoto Naoki , Honda Mitsuo 
Published: August 2004

ABSTRACTTo evaluate immunity induced by a novel DNA prime-boost regimen, we constructed a DNA plasmid encoding thegagandpolgenes from simian immunodeficiency virus (SIV) (SIVgag/polDNA), in addition to a replication-deficient vaccinia virus strain DIs recombinant expressing SIVgagandpolgenes (rDIsSIVgag/pol). In mice, priming with SIVgag/polDNA, followed by rDIsSIVgag/polinduced an SIV-specific lymphoproliferative response that was mediated by a CD4+-T-lymphocyte subset. Immunization with either vaccine alone was insufficient to induce high levels of proliferation or Th1 responses in the animals. The prime-boost regimen also induced SIV Gag-specific cellular responses based on gamma interferon secretion, as well as cytotoxic-T-lymphocyte responses. Thus, the regimen of DNA priming and recombinant DIs boosting induced Th1-type cell-mediated immunity, which was associated with resistance to viral challenge with wild-type vaccinia virus expressing SIVgag/pol, suggesting that this new regimen may hold promise as a safe and effective vaccine against human immunodeficiency virus type 1.
High Levels of Human Immunodeficiency Virus Infection of CD8 Lymphocytes Expressing CD4 In Vivo
Authors: Cochrane Alexandra , Imlach Stuart , Leen Clifford , Scott Gordon , Kennedy Dermot , Simmonds Peter 
Published: August 2004

ABSTRACTHuman immunodeficiency virus (HIV)-infected CD8 lymphocytes have been reported in vivo, but the mechanism of infection remains unclear. Experiments using the thy/hu mouse model support export of intrathymically infected CD8 precursors, while recent in vitro data suggest that mature CD8 lymphocytes upregulate CD4 upon activation (generating a CD8brightCD4dimphenotype) and are susceptible to HIV infection. To determine whether these mechanisms operate in vivo and to assess their relative importance in the generation of circulating HIV-infected CD8 lymphocytes, we quantified HIV long terminal repeat (LTR) DNA in CD8+CD4−and CD8brightCD4dimlymphocytes isolated from HIV-infected individuals by fluorescence-activated cell sorting. HIV infection of CD8 lymphocytes was demonstrated in 17 of 19 subjects, with a significant inverse relationship between level of infection and CD4 lymphocyte count (R= −0.73;P< 0.001). The level of HIV infection of CD8brightCD4dimlymphocytes was significantly higher (median, 1,730 HIV LTR copies/106cells;n= 9) than that of CD8+CD4−lymphocytes (undetectable in seven of nine individuals;P< 0.01) and approached that of CD4 lymphocytes from the same individuals (median, 3,660 HIV LTR copies/106cells). CD8brightCD4dimlymphocytes represented 0.8 to 3.3% of total CD8 lymphocytes and were most prevalent in the memory subset. Thus, HIV-infected CD8 lymphocytes commonly circulate in HIV-infected individuals and are generated through infection of activated CD8 lymphocytes rather than through export of intrathymically infected precursors. The high level of infection of CD8brightCD4dimlymphocytes could have a direct role in the decline in CD8 lymphocyte function that accompanies HIV disease progression.
Rheumatoid Factors Induce Signaling from B Cells, Leading to Epstein-Barr Virus and B-Cell Activation
Authors: Yang Lixin , Hakoda Masayuki , Iwabuchi Kazuya , Takeda Tsuyoshi , Koike Takao , Kamatani Naoyuki , Takada Kenzo 
Published: August 2004

ABSTRACTB-cell antigen receptor signaling is initiated upon binding of the antigen to membrane-bound immunoblobulin (Ig), and the anti-Ig antibody (Ab) mimics this signaling. In B cells latently infected with Epstein-Barr virus (EBV), the same signals induce virus activation. We examine here whether rheumatoid factors (RFs), autoantibodies directed against the Fc portion of IgG, induce EBV and B-cell activation. As a source of RFs, RF-producing lymphoblastoid cell line (LCL) clones were isolated from peripheral blood mononuclear cells (PBMC) and synovial cells from patients with rheumatoid arthritis (RA) by EBV transformation. Burkitt's lymphoma-derived Akata cells, which are highly responsive to EBV activation by anti-Ig Abs, were used for the assay of EBV activation. Akata cells expressed IgG3 as membrane-bound Ig. RFs from a synovium-derived LCL were directed to IgG3 and induced EBV activation in 16 to 18% of Akata cells, whereas RFs from another synovium-derived LCL were directed to IgG1 and did not induce EBV activation. Pretreatment of RFs with the purified Fc fragment of human IgG completely abolished EBV activation. Furthermore, B-cell activation was assessed by incorporation of [3H]thymidine. RFs from synovium-derived LCLs efficiently induced B-cell activation, and the addition of CD40 ligand had a synergistic effect. On the other hand, RFs from PBMC-derived LCLs were polyreactive, had a lower affinity to IgG, and did not induce EBV and B-cell activation. The present findings imply a possible role for RFs as EBV and B-cell activators.
Poly(ADP-Ribose) Polymerase 1 Binds to Kaposi's Sarcoma-Associated Herpesvirus (KSHV) Terminal Repeat Sequence and Modulates KSHV Replication in Latency
Authors: Ohsaki Eriko , Ueda Keiji , Sakakibara Shuhei , Do Eunju , Yada Kaori , Yamanishi Koichi 
Published: August 2004

ABSTRACT

During latency, Kaposi's sarcoma-associated herpesvirus (KSHV) is thought to replicate once and to be partitioned in synchrony with the cell cycle of the host. In this replication cycle, the KSHV terminal repeat (TR) sequence functions as a replication origin, assisted by the latency-associated nuclear antigen (LANA). Thus, TR seems to function as a
cis
element for the replication and partitioning of the KSHV genome. Viral replication and partitioning are also likely to require cellular factors that interact with TR in either a LANA-dependent or -independent manner. Here, we sought to identify factors that associate with TR by using a TR DNA column and found that poly(ADP-ribose) polymerase 1 (PARP1) and known replication factors, including ORC2, CDC6, and Mcm7, bound to TR. PARP1 bound directly to a specific region within TR independent of LANA, and LANA was poly(ADP-ribosyl)ated by PARP1. Drugs such as hydroxyurea and niacinamide, which raise or lower PARP activity, respectively, affected the virus copy number in infected cells. Thus, the poly(ADP-ribosyl)ation status of LANA appears to affect the replication and/or maintenance of the viral genome. Drugs that specifically up-regulate PARP activity may lead to the disappearance of latent KSHV.
Activation of the Tumor-Specific Death Effector Apoptin and Its Kinase by an N-Terminal Determinant of Simian Virus 40 Large T Antigen
Authors: Zhang Ying-Hui , Kooistra Klaas , Pietersen Alexandra , Rohn Jennifer L. , Noteborn Mathieu H. M. 
Published: August 2004

ABSTRACT
Apoptin, a viral death protein derived from chicken anemia virus, displays a number of tumor-specific behaviors. In particular, apoptin is phosphorylated, translocates to the nucleus, and induces apoptosis specifically in tumor or transformed cells, whereas it is nonphosphorylated and remains primarily inactive in the cytoplasm of nontransformed normal cells. Here, we show that in normal cells apoptin can also be activated by the transient transforming signals conferred by ectopically expressed simian virus 40 (SV40) large T antigen (LT), which rapidly induces apoptin's phosphorylation, nuclear accumulation, and the ability to induce apoptosis. Further analyses with mutants of LT showed that the minimum domain capable of inducing all three of apoptin's tumor-specific properties resided in the N-terminal J domain, a sequence which is largely shared by SV40 small t antigen (st). Interestingly, the J domain in st, which lacks its own nuclear localization signal (NLS), required nuclear localization to activate apoptin. These results reveal the existence of a cellular pathway shared by conditions of transient transformation and the stable cancerous or precancerous state, and they support a model whereby a transient transforming signal confers on apoptin both the upstream activity of phosphorylation and the downstream activity of nuclear accumulation and apoptosis induction. Such a pathway may reflect a general lesion contributing to human cancers.
Identification and Characterization of Severe Acute Respiratory Syndrome Coronavirus Replicase Proteins
Authors: Prentice Erik , McAuliffe Josephine , Lu Xiaotao , Subbarao Kanta , Denison Mark R. 
Published: August 2004

ABSTRACT
The severe acute respiratory syndrome coronavirus (SARS-CoV) encodes proteins required for RNA transcription and genome replication as large polyproteins that are proteolytically processed by virus-encoded proteinases to produce mature replicase proteins. In this report, we generated antibodies against SARS-CoV predicted replicase protein and used the antibodies to identify and characterize 12 of the 16 predicted mature replicase proteins (nsp1, nsp2, nsp3, nsp4, nsp5, nsp8, nsp9, nsp12, nsp13, nsp14, nsp15, and nsp16) in SARS-CoV-infected Vero cells. Immunoblot analysis of infected-cell lysates identified proteins of the predicted sizes. Immunofluorescence microscopy detected similar patterns of punctate perinuclear and distributed cytoplasmic foci with all replicase antibodies and as early as 6 h postinfection. Dual-labeling studies demonstrated colocalization of replicase protein nsp8 with nsp2 and nsp3 in cytoplasmic complexes and also with LC3, a protein marker for autophagic vacuoles. Antibodies directed against mouse hepatitis virus (MHV) virions and against the putative RNA-dependent RNA polymerase (Pol) detected SARS-CoV nucleocapsid and nsp12 (Pol), respectively, in SARS-CoV-infected Vero cells. These results confirm the predicted protein processing pattern for mature SARS-CoV replicase proteins, demonstrate localization of replicase proteins to cytoplasmic complexes containing markers for autophagosome membranes, and suggest conservation of protein epitopes in the replicase and nucleocapsid of SARS-CoV and the group II coronavirus, MHV. Further, the results demonstrate the ability of replicase antibodies to detect SARS-CoV-infected cells as early as 6 h postinfection and thus represent important tools for studies of SARS-CoV replication, inhibition, and diagnosis.
A Single Amino Acid Substitution in the Envelope Protein of Chimeric Yellow Fever-Dengue 1 Vaccine Virus Reduces Neurovirulence for Suckling Mice and Viremia/Viscerotropism for Monkeys
Authors: Guirakhoo F. , Zhang Z. , Myers G. , Johnson B. W. , Pugachev K. , Nichols R. , Brown N. , Levenbook I. , Draper K. , Cyrek S. , Lang J. , Fournier C. , Barrere B. , Delagrave S. , Monath T. P. 
Published: August 2004

ABSTRACT

A chimeric yellow fever-dengue 1 (ChimeriVax-DEN1) virus was produced by the transfection of Vero cells with chimeric in vitro RNA transcripts. The cell culture supernatant was subjected to plaque purification for the identification of a vaccine candidate without mutations. Of 10 plaque-purified clones, 1 containing no mutation (clone J) was selected for production of the vaccine virus. During subsequent cell culture passaging of this clone for vaccine production, a single amino acid substitution (K to R) occurred in the envelope (E) protein at residue 204 (E204) (F. Guirakhoo, K. Pugachev, Z. Zhang, G. Myers, I. Levenbook, K. Draper, J. Lang, S. Ocran, F. Mitchell, M. Parsons, N. Brown, S. Brandler, C. Fournier, B. Barrere, F. Rizvi, A. Travassos, R. Nichols, D. Trent, and T. Monath, J. Virol.
78:
4761-4775, 2004). The same mutation was observed in another clone (clone E). This mutation attenuated the virus in 4-day-old suckling mice inoculated by the intracerebral (i.c.) route and led to reduced viremia in monkeys inoculated by the subcutaneous or i.c. route. The histopathology scores of lesions in the brain tissue of monkeys inoculated with either the E204K or E204R virus were reduced compared to those for monkeys inoculated with the reference virus, a commercial yellow fever 17D vaccine (YF-VAX). Both viruses grew to significantly lower titers than YF-VAX in HepG2, a human hepatoma cell line. After intrathoracic inoculation into mosquitoes, both viruses grew to a similar level as YF-VAX, which was significantly lower than that of their wild-type DEN1 parent virus. A comparison of the E-protein structures of nonmutant and mutant viruses suggested the appearance of new intramolecular bonds between residues 204R, 261H, and 257E in the mutant virus. These changes may be responsible for virus attenuation through a change in the pH threshold for virus envelope fusion with the host cell membrane.
Minors’ tobacco possession law violations and intentions to smoke: implications for tobacco control
Authors: Gottlieb N H , Loukas A , Corrao M , McAlister A , Snell C , Huang P P 
Published: August 2004

Objectives:To test: (1) whether citation under the Minors in Possession (MIP) law, vicarious citation (knowing someone who was cited), and threat of driving licence suspension are associated with decreased intentions to smoke next year; and (2) whether the policy is differentially enforced.Subjects:28 249 white, Hispanic, and African American students in grades 6–12 (11–18 years old) participated in the study.Method:The 86 item anonymous Texas Youth Tobacco Survey was completed by students attending 37 schools in 14 east and central Texas communities.Results:Hierarchical linear modelling showed that MIP citation was unrelated to the future smoking intentions of most youth. However, there was a negative association between citation and smoking intentions for ever daily smoking youth at four schools. Threat of licence suspension was associated with a lower likelihood of future smoking intentions among ever daily smoking youth and vicarious citation did not deter youth from future smoking. African American and Hispanic youth had a higher probability of being cited than their peers.Conclusions:Threat of driving licence suspension has the intended effect upon youth who are/were committed smokers and MIP citation has the intended effect upon committed smokers at only four schools. However, differential enforcement of the law based on ethnicity may be occurring. Before drawing firm conclusions, current findings must be replicated with longitudinal data to determine the consequences of citation on subsequent tobacco use.
Short term patterns of early smoking acquisition
Authors: Wellman R J , DiFranza J R , Savageau J A , Dussault G F 
Published: August 2004

Objective:To describe short term patterns of smoking acquisition exhibited by adolescent smokers.Design:Interview records from the prospective development and assessment of nicotine dependence in youth study were examined retrospectively. Interviews were conducted three times per year over 30 months.Subjects:164 students in grades 7–9 (ages 12–15 years, 86 girls, 78 boys) who had used cigarettes at least twice.Main outcome measures:A continuous timeline of smoking activity, beginning with the subject’s first use of tobacco and continuing through follow up, was translated into six patterns—abstinent, sporadic, occasional, daily, escalating, and intermittent. Outcome measures were the proportion of subjects starting/ending in each pattern, and the number of transitions per subject between patterns.Results:There was a general but discontinuous progression from infrequent to more frequent use, with many interspersed periods of not smoking. Escalation to daily smoking was common after the development of dependence symptoms, but was rare among those who did not have symptoms. After the appearance of symptoms, both transitions to heavier daily smoking and attempts at cessation increased.Conclusions:Movement to heavier, more frequent smoking is generally unidirectional, although many youths attempt to quit one or more times. The appearance of any symptom of dependence altered the subsequent pattern of smoking behaviour. Future investigators might consider using more frequent data points and a continuous timeline to track smoking behaviour.
Prevalence and correlates of internet cigarette purchasing among adult smokers in New Jersey
Authors: Hrywna M , Delnevo C D , Staniewska D 
Published: August 2004

Objective:To examine the prevalence and correlates of internet cigarette purchasing among adult smokers.Design:Analysis of internet purchasing in data from a population based telephone survey of New Jersey households. Logistic regression was used to determine factors associated with internet cigarette purchasing, adjusting for year, demographic, and smoking behaviour variables.Participants:3447 current cigarette smokers pooled from three cross sectional surveys conducted in 2000, 2001, and 2002.Main outcome measures:Ever purchasing tobacco and usually buying cigarettes via the internet.Results:Among all current cigarette smokers, ever having purchased tobacco via the internet increased from 1.1% in 2000 to 6.7% in 2002 and usually buying cigarettes via the internet increased from 0.8% in 2000 to 3.1% in 2002. Among current cigarette smokers with internet access, ever having purchased tobacco via the internet was higher among those who reported smoking 31 or more cigarettes per day (adjusted odds ratio (OR) 3.9, 95% confidence interval (CI) 1.5 to 10.2) and those without a past year quit attempt (adjusted OR 1.8, 95% CI 1.1 to 3.0). Usually purchasing cigarettes via the internet was higher among those aged 45–64 years (adjusted OR 4.4, 95% CI 1.1 to 17.1) and who reported having their first cigarette ⩽ 30 minutes after waking (adjusted OR 3.3, 95% CI 1.2 to 9.2).Conclusions:Although higher prices are known to reduce the demand for cigarettes, internet cigarette purchasing is likely to weaken this effect, particularly among heavy, more dependent smokers who are less interested in quitting.
Public health foundations and the tobacco industry: lessons from Minnesota
Authors: Ibrahim J K , Tsoukalas T H , Glantz S A 
Published: August 2004

Objective:To investigate whether private foundations can be created in a way that will insulate them from attacks by the tobacco industry, using the Minnesota Partnership for Action Against Tobacco (MPAAT) as a case study.Design:Information was collected from internal tobacco industry documents, court documents, newspapers, and interviews with health advocates and elected officials.Results:The creation of MPAAT as an independent foundation did not insulate it from attacks by tobacco industry allies. During 2001–2002, MPAAT was repeatedly attacked by Attorney General Mike Hatch and major media, using standard tobacco industry rhetoric. This strategy of attack and demands for information were reminiscent of previous attacks on Minnesota’s Plan for Nonsmoking and Health and the American Stop Smoking Intervention Study (ASSIST). MPAAT was ultimately forced to restructure its programme to abandon effective community norm change interventions around smoke-free policies and replace them with less effective individual cessation interventions. Neither MPAAT nor other health advocates mounted an effective public response to these attacks, instead relying on the insider strategy of responding in court.Conclusion:It is not possible to avoid attacks by the tobacco industry or its political allies. Like programmes administered by government agencies, tobacco control foundations must be prepared for these attacks, including a proactive plan to educate the public about the principles of community based tobacco control. Public health advocates also need to be willing to take prompt action to defend these programmes and hold public officials who attack tobacco control programmes accountable for their actions.