bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective management of smoking in an oral dysplasia clinic in London
Authors: Poate TWJ , Warnakulasuriya S
Published: November 2005

Background:  Precancerous lesions precede the development of oral cancer; of several clinical types the most common is leukoplakia. The risk factors include tobacco and excess alcohol use and diets low in antioxidants. Studies concerning the management of risk factors related to oral precancer are meager.

Objectives:  We investigated the effectiveness of smoking cessation at a dysplasia clinic among patients followed up for at least for 12 months.

Methods:  Data from case notes relating to180 patients with white and red patches of oral mucosa (excluding other benign disorders confirmed by biopsy findings) attending a dysplasia clinic at a teaching hospital in London and seen by one consultant between 1993 and 2003 were transcribed. Effect of referring to a smoker's clinic to receive specialist help was evaluated against brief advice given at the dysplasia clinic ± medications.

Results:  The mean age at the first visit was 48.5 years (±12.5), 65% were male, and 88% were white European. One hundred and sixty‐two patients (90%) had used tobacco and 83% were current smokers. Of the smokers 95% had smoked over 10 years, the majority smoking over 10 cigarettes per day. Nine were alcohol misusers including two binge drinkers. One hundred and forty‐six were diagnosed with oral leukoplakia, 16 with non‐homogeneous types (speckled or nodular). Three patients were diagnosed with an erythroplakia. Nineteen per cent exhibited the presence of dysplasia and one subject had in situ carcinoma. Five patients in the sample quit smoking prior to arrival in the dysplasia clinic. Twenty‐seven cases (20%) with oral leukoplakia quit smoking while registered as a patient at the dysplasia clinic: 17 of 100 subjects quit with brief advice ± medications and 10 of 30 following referral to the smoker's clinic. The difference between the two groups was significant for point prevalence abstinence at the last visit to the clinic (minimum 12 months follow up). Out of a total of 180 precancer cases managed in the dysplasia clinic (mean follow up 4.2 years) three patients subsequently developed invasive carcinoma during follow up.

Conclusions:  Smoking cessation needs to be an integral component of management of cases attending a dysplasia clinic and referring to smoker's clinics could help to improve the effectiveness of managing patients with oral precancer to quit smoking.
Relationship of periodontal bacteria and Porphyromonas gingivalis fimA variations with phenytoin‐induced gingival overgrowth
Authors: Akiyama S , Amano A , Kato T , Takada Y , Kimura KR , Morisaki I
Published: November 2005

Objectives:  We investigated the relationship between phenytoin‐induced gingival overgrowth (GO) and the harboring of periodontal bacteria.

Materials and methods:  Periodontal conditions and subgingival bacterial profiles were examined in 450 sites of 75 subjects. A polymerase chain reaction method was used to detect six bacterial species; Porphyromonas gingivalis (Pg), Actinobacillus actinomycetemcomitans (Aa), Tannerella forsythia, Treponema denticola (Td), Prevotella intermedia (Pi), and Prevotella nigrescens (Pn). Genetic variations of the Pg fimA gene were also examined. Bacterial occurrence was compared with the severity of GO, and alterations in the bacterial occurrence rate and quantities were monitored following periodontal treatment.

Results:  The occurrences of Aa, Td, Pi, Pn, and Pg with type II fimA (type II Pg) were significantly associated with the severity of GO. Td occurrence was reduced in association with gingival improvement following ultrasonic scaling, however, no such relationship was observed with Aa, Pi, Pn, and Pg. In addition, Pg and Pi markedly persisted after treatment. Clinical improvement of the sites, following an Er:YAG laser treatment, significantly associated with quantitative reduction of Pg in improved sites, however, not that of Pi.

Conclusion:  Type II Pg and Td were each found to have a significant relationship with the development and deterioration of GO.
A Point Mutation within the Replicase Gene Differentially Affects Coronavirus Genome versus Minigenome Replication
Authors: Galán Carmen , Enjuanes Luis , Almazán Fernando
Published: November 2005

During the construction of the
transmissible gastroenteritis virus
(TGEV) full-length cDNA clone, a point mutation at position 637 that was present in the defective minigenome DI-C was maintained as a genetic marker. Sequence analysis of the recovered viruses showed a reversion at this position to the original virus sequence. The effect of point mutations at nucleotide 637 was analyzed by reverse genetics using a TGEV full-length cDNA clone and cDNAs from TGEV-derived minigenomes. The replacement of nucleotide 637 of TGEV genome by a T, as in the DI-C sequence, or an A severely affected virus recovery from the cDNA, yielding mutant viruses with low titers and small plaques compared to those of the wild type. In contrast, T or A at position 637 was required for minigenome rescue in
trans
by the helper virus. No relationship between these observations and RNA secondary-structure predictions was found, indicating that mutations at nucleotide 637 most likely had an effect at the protein level. Nucleotide 637 occupies the second codon position at amino acid 108 of the pp1a polyprotein. This position is predicted to map in the N-terminal polyprotein papain-like proteinase (PLP-1) cleavage site at the p9/p87 junction. Replacement of G-637 by A, which causes a drastic amino acid change (Gly to Asp) at position 108, affected PLP-1-mediated cleavage in vitro. A correlation was found between predicted cleaving and noncleaving mutations and efficient virus rescue from cDNA and minigenome amplification, respectively.
Kaposi's Sarcoma-Associated Herpesvirus Induction of AP-1 and Interleukin 6 during Primary Infection Mediated by Multiple Mitogen-Activated Protein Kinase Pathways
Authors: Xie Jianping , Pan Hongyi , Yoo Seungmin , Gao Shou-Jiang
Published: November 2005

Kaposi's sarcoma is an angioproliferative disseminated tumor of endothelial cells linked to infection with Kaposi's sarcoma-associated herpesvirus (KSHV). AP-1 transcription factors are involved in diverse biological processes, including infection and replication of viruses, cell growth, oncogenesis, angiogenesis, and invasion of cancer cells. Here we show that KSHV activates AP-1 during primary infection. The activation of AP-1 at the early stage of KSHV infection is mainly mediated by virus entry events. Concurrently, KSHV infection strongly activates MEK, JNK, and to a lesser extent, p38 mitogen-activated protein kinase (MAPK) pathways. Specific inhibitors or dominant negative constructs of MEK and JNK completely abolish AP-1 activation by KSHV, while those of p38 reduce it by half. Furthermore, individual MAPK pathways differentially regulate KSHV activation of AP-1 components. KSHV activation of AP-1 leads to the transcriptional induction of interleukin 6 (IL-6), which is inhibited by inhibitors or dominant negative constructs of MAPK pathways. Together, these results demonstrate that KSHV induces AP-1 and IL-6 during primary infection by modulating multiple MAPK pathways. Because of the diverse roles of IL-6, AP-1, and MAPK pathways in viral infection and tumor induction and promotion, these results have important implications in the pathogenesis of KSHV-induced malignancies.
A Vesicular Stomatitis Virus Recombinant Expressing Granulocyte-Macrophage Colony-Stimulating Factor Induces Enhanced T-Cell Responses and Is Highly Attenuated for Replication in Animals
Authors: Ramsburg Elizabeth , Publicover Jean , Buonocore Linda , Poholek Amanda , Robek Michael , Palin Amy , Rose John K.
Published: November 2005

Live attenuated vectors based on recombinant vesicular stomatitis viruses (rVSVs) expressing foreign antigens are highly effective vaccines in animal models. In this study, we report that an rVSV (VSV-GMCSF1) expressing high levels of murine granulocyte-macrophage colony-stimulating factor (GM-CSF) from the first position in the viral genome is highly attenuated in terms of viral dissemination and pathogenesis after intranasal delivery to mice. However, this highly attenuated virus generated antibody and T-cell responses equivalent to those induced by a control virus expressing enhanced green fluorescent protein (EGFP) from the first position (VSV-EGFP1). The better containment and clearance of VSV-GMCSF1 may be due to enhanced recruitment of macrophages to the site of infection but is not explained by a greater induction of interferons. The primary CD8 T-cell and neutralizing antibody responses to VSV-GMCSF1 were equivalent to those generated by VSV-EGFP1, while the CD8 T-cell memory and recall responses to the vector were enhanced in mice infected with VSV-GMCSF1. It is likely that the GM-CSF produced by immunization with this virus results in an enhanced recruitment of antigen-presenting cells, leading to better acute and long-term T-cell responses. This recruitment appears to cancel out any negative effect of viral attenuation on immunogenicity.
Humoral and Cellular Immune Response to RNA Immunization with Flavivirus Replicons Derived from Tick-Borne Encephalitis Virus
Authors: Aberle Judith H. , Aberle Stephan W. , Kofler Regina M. , Mandl Christian W.
Published: November 2005

A new vaccination principle against flaviviruses, based on a tick-borne encephalitis virus (TBEV) self-replicating noninfectious RNA vaccine that produces subviral particles, has recently been introduced (R. M. Kofler, J. H. Aberle, S. W. Aberle, S. L. Allison, F. X. Heinz, and C. W. Mandl, Proc. Natl. Acad. Sci. USA7:1951-1956, 2004). In this study, we evaluated the potential of the self-replicating RNA vaccine in mice in comparison to those of live, attenuated vaccines and a formalin-inactivated whole-virus vaccine (ImmunInject). For this purpose, mice were immunized using gene gun-mediated application of the RNA vaccine and tested for CD8+T-cell responses, long-term duration, neutralizing capacity, and isotype profile of specific antibodies and protection against lethal virus challenge. We demonstrate that the self-replicating RNA vaccine induced a broad-based, humoral and cellular (Th1 and CD8+T-cell response) immune response comparable to that induced by live vaccines and that it protected mice from challenge. Even a single immunization with 1 μg of the replicon induced a long-lasting antibody response, characterized by high neutralizing antibody titers, which were sustained for at least 1 year. Nevertheless, it was possible to boost this response further by a second injection with the RNA vaccine, even in the presence of a concomitant CD8+T-cell response. In this way it was possible to induce a balanced humoral and cellular immune response, similar to infection-induced immunity but without the safety hazards of infectious agents. The results also demonstrate the value of TBEV replicon RNA for inducing protective long-lasting antiviral responses.
Restriction of Feline Immunodeficiency Virus by Ref1, Lv1, and Primate TRIM5α Proteins
Authors: Saenz Dyana T. , Teo Wulin , Olsen John C. , Poeschla Eric M.
Published: November 2005

The Ref1 and Lv1 postentry restrictions in human and monkey cells have been analyzed for lentiviruses in the primate and ungulate groups, but no data exist for the third (feline) group. We compared feline immunodeficiency virus (FIV) to other restricted (human immunodeficiency virus type 1 [HIV-1], equine infectious anemia virus [EIAV]) and unrestricted (NB-tropic murine leukemia virus [NB-MLV]) retroviruses across wide ranges of viral inputs in cells from multiple primate and nonprimate species. We also characterized restrictions conferred to permissive feline and canine cells engineered to express rhesus and human TRIM5α proteins and performed RNA interference (RNAi) against endogenous TRIM5α. We find that expression of rhesus or human TRIM5α proteins in feline cells restricts FIV, impairing pseudotyped vector transduction and viral replication, but rhesus TRIM5α is more restricting than human TRIM5α. Notably, however, canine cells did not support restriction by human TRIM5α and supported minimal restriction by rhesus TRIM5α, suggesting that these proteins may not function autonomously or that a canine factor interferes. Stable RNAi knockdown of endogenous rhesus TRIM5α resulted in marked increases in FIV and HIV-1 infectivities while having no effect on NB-MLV. A panel of nonprimate cell lines varied widely in susceptibility to lentiviral vector transduction, but normalized FIV and HIV-1 vectors varied concordantly. In contrast, in human and monkey cells, relative restriction of FIV compared to HIV-1 varied from none to substantial, with the greatest relative infectivity deficit for FIV vectors observed in human T-cell lines. Endogenous and introduced TRIM5α restrictions of FIV could be titrated by coinfections with FIV, HIV-1, or EIAV virus-like particles. Arsenic trioxide had complex and TRIM5α-independent enhancing effects on lentiviral but not NB-MLV infection. Implications for human gene therapy are discussed.
Contributions of Matrix and Large Protein Genes of the Measles Virus Edmonston Strain to Growth in Cultured Cells as Revealed by Recombinant Viruses
Authors: Tahara Maino , Takeda Makoto , Yanagi Yusuke
Published: November 2005

The Edmonston strain of measles virus (MV) was obtained by sequential passages of the original isolate in various cultured cells. Although attenuated in vivo, it grows efficiently in most primate cell lines. Previous studies have revealed that MV tropism cannot be solely explained by the use of CD150 and/or CD46 as a cellular receptor. In order to evaluate the contributions of individual genes of the Edmonston strain to growth in cultured cells, we generated a series of recombinant viruses in which part of the genome of the clinical isolate IC-B (which uses CD150 as a receptor) was replaced with the corresponding sequences of the Edmonston strain. The recombinant virus possessing the Edmonston hemagglutinin (H) gene (encoding the receptor-binding protein) grew as efficiently in Vero cells as the Edmonston strain. Those viruses having either the matrix (M) or large (L) protein gene from the Edmonston strain could also replicate well in Vero cells, although they entered them at low efficiencies. P64S and E89K substitutions were responsible for the ability of the M protein to make virus grow efficiently in Vero cells, while the first half of the Edmonston L gene was important for better replication. Despite efficient growth in Vero cells, the recombinant viruses with these mutations had growth disadvantage in CD150-positive lymphoid B95a cells. Thus, not only the H gene but also the M and L genes contribute to efficient replication of the Edmonston strain in some cultured cells.
Modulation of HLA-G Expression in Human Neural Cells after Neurotropic Viral Infections
Authors: Lafon Monique , Prehaud Christophe , Megret Françoise , Lafage Mireille , Mouillot Gaël , Roa Michèle , Moreau Philippe , Rouas-Freiss Nathalie , Carosella Edgardo D.
Published: November 2005

HLA-G is a nonclassical human major histocompatibility complex class I molecule. It may promote tolerance, leading to acceptance of the semiallogeneic fetus and tumor immune escape. We show here that two viruses—herpes simplex virus type 1 (HSV-1), a neuronotropic virus inducing acute infection and neuron latency; and rabies virus (RABV), a neuronotropic virus triggering acute neuron infection—upregulate the neuronal expression of several HLA-G isoforms, including HLA-G1 and HLA-G5, the two main biologically active isoforms. RABV induces mostly HLA-G1, and HSV-1 induces mostly HLA-G3 and HLA-G5. HLA-G expression is upregulated in infected cells and neighboring uninfected cells. Soluble mediators, such as beta interferon (IFN-β) and IFN-γ, upregulate HLA-G expression in uninfected cells. The membrane-bound HLA-G1 isoform was detected on the surface of cultured RABV-infected neurons but not on the surface of HSV-1-infected cells. Thus, neuronotropic viruses that escape the host immune response totally (RABV) or partially (HSV-1) regulate HLA-G expression on human neuronal cells differentially. HLA-G may therefore be involved in the escape of certain viruses from the immune response in the nervous system.
Episomal Maintenance of Plasmids with Hybrid Origins in Mouse Cells
Authors: Silla Toomas , Hääl Ingrid , Geimanen Jelizaveta , Janikson Kadri , Abroi Aare , Ustav Ene , Ustav Mart
Published: November 2005

Bovine papillomavirus type 1 (BPV1), Epstein-Barr virus (EBV), and human herpesvirus 8 genomes are stably maintained as episomes in dividing host cells during latent infection. The mitotic segregation/partitioning function of these episomes is dependent on single viral protein with specific DNA-binding activity and its multimeric binding sites in the viral genome. In this study we show that, in the presence of all essential viral
trans
factors, the segregation/partitioning elements from both BPV1 and EBV can provide the stable maintenance function to the mouse polyomavirus (PyV) core origin plasmids but fail to do so in the case of complete PyV origin. Our study is the first which follows BPV1 E2- and minichromosome maintenance element (MME)-dependent stable maintenance function with heterologous replication origins. In mouse fibroblast cell lines expressing PyV large T antigen (LT) and either BPV1 E2 or EBV EBNA1, the long-term episomal replication of plasmids carrying the PyV minimal origin together with the MME or family of repeats (FR) element can be monitored easily for 1 month under nonselective conditions. Our data demonstrate clearly that the PyV LT-dependent replication function and the segregation/partitioning function of the BPV1 or EBV are compatible in certain, but not all, configurations. The quantitative analysis indicates a loss rate of 6% per cell, doubling in the case of MME-dependent plasmids, and 13% in the case of FR-dependent plasmids in nonselective conditions. Our data clearly indicate that maintenance functions from different viruses are principally interexchangeable and can provide a segregation/partitioning function to different heterologous origins in a variety of cells.
Soluble Receptor-Mediated Targeting of Mouse Hepatitis Coronavirus to the Human Epidermal Growth Factor Receptor
Authors: Würdinger T. , Verheije M. H. , Broen K. , Bosch B. J. , Haijema B. J. , de Haan C. A. M. , van Beusechem V. W. , Gerritsen W. R. , Rottier P. J. M.
Published: November 2005

The mouse hepatitis coronavirus (MHV) infects murine cells by binding of its spike (S) protein to murine CEACAM1a. The N-terminal part of this cellular receptor (soR) is sufficient for S binding and for subsequent induction of the conformational changes required for virus-cell membrane fusion. Here we analyzed whether these characteristics can be used to redirect MHV to human cancer cells. To this end, the soR domain was coupled to single-chain monoclonal antibody 425, which is directed against the human epidermal growth factor receptor (EGFR), resulting in a bispecific adapter protein (soR-425). The soR and soR-425 proteins, both produced with the vaccinia virus system, were able to neutralize MHV infection of murine LR7 cells. However, only soR-425 was able to target MHV to human EGFR-expressing cancer cells. Interestingly, the targeted infections induced syncytium formation. Furthermore, the soR-425-mediated infections were blocked by heptad repeat-mimicking peptides, indicating that virus entry requires the regular S protein fusion process. We conclude that the specific spike-binding property of the CEACAM1a N-terminal fragment can be exploited to direct the virus to selected cells by linking it to a moiety able to bind a receptor on those cells. This approach might be useful in the development of tumor-targeted coronaviruses.
Basic Residues in Hypervariable Region 1 of Hepatitis C Virus Envelope Glycoprotein E2 Contribute to Virus Entry
Authors: Callens Nathalie , Ciczora Yann , Bartosch Birke , Vu-Dac Ngoc , Cosset François-Loïc , Pawlotsky Jean-Michel , Penin François , Dubuisson Jean
Published: November 2005

The N terminus of hepatitis C virus (HCV) envelope glycoprotein E2 contains a hypervariable region (HVR1) which has been proposed to play a role in viral entry. Despite strong amino acid variability, HVR1 is globally basic, with basic residues located at specific sequence positions. Here we show by analyzing a large number of HVR1 sequences that the frequency of basic residues at each position is genotype dependent. We also used retroviral pseudotyped particles (HCVpp) harboring genotype 1a envelope glycoproteins to study the role of HVR1 basic residues in entry. Interestingly, HCVpp infectivity globally increased with the number of basic residues in HVR1. However, a shift in position of some charged residues also modulated HCVpp infectivity. In the absence of basic residues, infectivity was reduced to the same level as that of a mutant deleted of HVR1. We also analyzed the effect of these mutations on interactions with some potential HCV receptors. Recognition of CD81 was not affected by changes in the number of charged residues, and we did not find a role for heparan sulfates in HCVpp entry. The involvement of the scavenger receptor class B type I (SR-BI) was indirectly analyzed by measuring the enhancement of infectivity of the mutants in the presence of the natural ligand of SR-BI, high-density lipoproteins (HDL). However, no correlation between the number of basic residues within HVR1 and HDL enhancement effect was observed. Despite the lack of evidence of the involvement of known potential receptors, our results demonstrate that the presence of basic residues in HVR1 facilitates virus entry.
Genetic and Stochastic Influences on the Interaction of Human Immunodeficiency Virus Type 1 and Cytotoxic T Lymphocytes in Identical Twins
Authors: Yang Otto O. , Church Joseph , Kitchen Christina M. R. , Kilpatrick Ryan , Ali Ayub , Geng Yongzhi , Killian M. Scott , Sabado Rachel Lubong , Ng Hwee , Suen Jeffrey , Bryson Yvonne , Jamieson Beth D. , Krogstad Paul
Published: November 2005

Human immunodeficiency virus type 1 (HIV-1) evolves in vivo under selective pressure from CD8
+
T-lymphocyte (CTL) responses, which are in turn determined by host and viral genetic factors, such as restricting major histocompatibility complex molecules and the available viral epitope sequences. However, CTL are derived stochastically through the random gene rearrangements to produce T-cell receptors (TCR), and the relative impact of genetic versus stochastic processes on CTL targeting of HIV and immune-driven viral evolution is unclear. Here we evaluate identical twins infected with HIV-1 as neonates from a common blood transfusion, with subsequently similar environmental exposures, thereby allowing controlled comparisons of CTL targeting and viral evolution. Seventeen years after infection, their CTL targeting of HIV-1 was remarkably similar. In contrast, their overall TCR profiles were highly dissimilar, and a dominant epitope was recognized by distinctly different TCR in each twin. Furthermore, their viral epitopes had diverged, and there was ongoing viral phylogenetic divergence between the twins between 12 and 17 years after infection. These results indicate that while CTL targeting is predominately genetically determined, stochastic influences render the interaction of HIV-1 and host immunity, and therefore viral escape and CTL efficacy, unpredictable.
Division of Labor within Human Immunodeficiency Virus Integrase Complexes: Determinants of Catalysis and Target DNA Capture
Authors: Diamond Tracy L. , Bushman Frederic D.
Published: November 2005

Following the completion of reverse transcription, the human immunodeficiency virus integrase (IN) enzyme covalently links the viral cDNA to a host cell chromosome. An IN multimer carries out this reaction, but the roles of individual monomers within the complex are mostly unknown. Here we analyzed the distribution of functions for target DNA capture and catalysis within the IN multimer. We used forced complementation between pairs of IN deletion derivatives in vitro as a tool for probing
cis-trans
relationships and analyzed amino acid substitutions affecting either catalysis or target site selection within these complementing complexes. This allowed the demonstration that the IN variant contributing the active catalytic domain was also responsible for recognition of the integration target DNA. We were further able to establish that a single monomer is responsible for both functions by use of assay mixtures containing three different IN genotypes. These data specify the ligands bound at the catalytically relevant IN monomer and allow more-specific modeling of the mechanism of inhibitors that also bind this surface of IN.
Production of Infectious Human Cytomegalovirus Virions Is Inhibited by Drugs That Disrupt Calcium Homeostasis in the Endoplasmic Reticulum
Authors: Isler Jennifer A. , Maguire Tobi Goldberg , Alwine James C.
Published: November 2005

We previously reported that human cytomegalovirus (HCMV) infection induces endoplasmic reticulum (ER) stress, resulting in activation of the unfolded protein response (UPR). Although some normal consequences of UPR activation (e.g., translation attenuation) are detrimental to viral infection, we have previously shown that HCMV infection adapts the UPR to benefit the viral infection (14). For example, UPR-induced translation attenuation is inhibited by viral infection, while potentially beneficial aspects of the UPR are maintained. In the present work, we tested the ability of HCMV to overcome a robust induction of the UPR by the drugs thapsigargin and clotrimazole (CLT), which disrupt ER calcium homeostasis. A 24-h treatment with these drugs beginning at 48, 72, or 96 h postinfection (hpi) completely inhibited further production of infectious virions. HCMV could not overcome the inhibition of global translation by CLT; however, between 48 and 72 hpi, HCMV overcame translational inhibition caused by thapsigargin. Despite the restoration of translation in thapsigargin, the accumulation of immediate-early and early gene products was modestly retarded (50% or less), whereas the accumulation of an early-late and late gene product was significantly retarded. Electron microscopic analysis shows that the drugs severely disrupt the maturation of HCMV virions. This can be accounted for by both the retarded accumulation of late gene products and the drug-induced depletion of ER calcium, which disrupts critical cellular functions needed for maturation.
Overexpression of Tumor Necrosis Factor Alpha by a Recombinant Rabies Virus Attenuates Replication in Neurons and Prevents Lethal Infection in Mice
Authors: Faber Milosz , Bette Michael , Preuss Mirjam A. R. , Pulmanausahakul Rojjanaporn , Rehnelt Jennifer , Schnell Matthias J. , Dietzschold Bernhard , Weihe Eberhard
Published: November 2005

The effect of tumor necrosis factor alpha (TNF-α) on rabies virus (RV) infection of the mouse central nervous system (CNS) was studied, using recombinant RV engineered to express either soluble TNF-α [SPBN-TNF-α(+)] or insoluble membrane-bound TNF-α [SPBN-TNF-α(MEM)]. Growth curves derived from infections of mouse neuroblastoma NA cells revealed significantly less spread and production of SPBN-TNF-α(+) than of SPBN-TNF-α(MEM) or SPBN-TNF-α(−), which carries an inactivated TNF-α gene. The expression of soluble or membrane-bound TNF-α was not associated with increased cell death or induction of alpha/beta interferons. Brains of mice infected intranasally with SPBN-TNF-α(+) showed significantly less virus spread than did mouse brains after SPBN-TNF-α(−) infection, and none of the SPBN-TNF-α(+)-infected mice succumbed to RV infection, whereas 80% of SPBN-TNF-α(−)-infected mice died. Reduced virus spread in SPBN-TNF-α(+)-infected mouse brains was paralleled by enhanced CNS inflammation, including T-cell infiltration and microglial activation. These data suggest that TNF-α exerts its protective activity in the brain directly through an as yet unknown antiviral mechanism and indirectly through the induction of inflammatory processes in the CNS.
Epstein-Barr-Virus-Encoded LMP2A Induces Primary Epithelial Cell Migration and Invasion: Possible Role in Nasopharyngeal Carcinoma Metastasis
Authors: Pegtel Dirk M. , Subramanian Aravind , Sheen Tzung-Shiahn , Tsai Ching-Hwa , Golub Todd R. , Thorley-Lawson David A.
Published: November 2005

Nonkeratinizing nasopharyngeal carcinomas (NPC) are >95% associated with the expression of the Epstein-Barr virus (EBV) LMP2A latent protein. However, the role of EBV, in particular, LMP2A, in tumor progression is not well understood. Using Affymetrix chips and a pattern-matching computational technique (neighborhood analysis), we show that the level of LMP2A expression in NPC biopsy samples correlates with that of a cellular protein, integrin-alpha-6 (ITGα6), that is associated with cellular migration in vitro and metastasis in vivo. We have recently developed a primary epithelial model from tonsil tissue to study EBV infection in epithelial cells. Here we report that LMP2A expression in primary tonsil epithelial cells causes them to become migratory and invasive, that ITGα6 RNA levels are up-regulated in epithelial cells expressing LMP2, and that ITGα6 protein levels are increased in the migrating cells. Blocking antibodies against ITGα6 abrogated LMP2-induced invasion through Matrigel by primary epithelial cells. Our results provide a link between LMP2A expression, ITGα6 expression, epithelial cell migration, and NPC metastasis and suggest that EBV infection may contribute to the high incidence of metastasis in NPC progression.
New Genotype of Avian Influenza H5N1 Viruses Isolated from Tree Sparrows in China
Authors: Kou Z. , Lei F. M. , Yu J. , Fan Z. J. , Yin Z. H. , Jia C. X. , Xiong K. J. , Sun Y. H. , Zhang X. W. , Wu X. M. , Gao X. B. , Li T. X.
Published: November 2005

The 2004 outbreaks of highly pathogenic avian influenza H5N1 disease in China led to a great poultry loss and society attention. A survey of avian influenza viruses was conducted on tree sparrows (
Passer montanus
) collected in China in 2004. Four viruses were isolated from free-living tree sparrows. The results of the whole-genome analysis indicated that an H5N1 virus with a new genotype is circulating among tree sparrows. The hemagglutinin and neuraminidase genes of the new genotype were derived from Gs/Gd/96-like viruses and the nuclear protein gene descended from the 2001 genotype A H5N1 viruses, while the other inner genes originated from an unknown influenza virus. In experimental infection, all four viruses were highly pathogenic to chickens but not pathogenic to ducks or mice. The four tree sparrow viruses were different from the 2003 tree sparrow strain (genotype Z) in Hong Kong. The results suggested that H5N1 viruses might be distributed widely in tree sparrows.
Human Cytomegalovirus Infection Induces Specific Hyperphosphorylation of the Carboxyl-Terminal Domain of the Large Subunit of RNA Polymerase II That Is Associated with Changes in the Abundance, Activity, and Localization of cdk9 and cdk7
Authors: Tamrakar Sama , Kapasi Anokhi J. , Spector Deborah H.
Published: November 2005

Human cytomegalovirus infection in the presence of the cyclin-dependent kinase (cdk) inhibitor roscovitine leads to changes in differential splicing and the polyadenylation of immediate early IE1/IE2 and UL37 transcripts (V. Sanchez, A. K. McElroy, J. Yen, S. Tamrakar, C. L. Clark, R. A. Schwartz, and D. H. Spector, J. Virol. 78:11219-11232, 2004). To determine if this was associated with specific phosphorylation of the C-terminal domain (CTD) of the RNA polymerase II (RNAP II) large subunit by cdk7/cyclin H and cdk9/cyclin T1, we examined the expression and localization of these kinases and the various phosphorylated forms of RNAP II. Infection resulted in increased RNAP II CTD phosphorylated on serines 2 and 5 and increased levels of activity of cdk7 and cdk9. At early times, cdk9 localizes with input viral DNA, and aggregates of cdk9 and cdk7 and a subset of Ser2-phosphorylated RNAP II colocalize with IE1/IE2 proteins adjacent to promyelocytic leukemia protein oncogenic domains. Later, cdk9 and Ser2-phosphorylated RNAP II form a nuclear punctate pattern; cdk7 resides in replication centers, and Ser5-phosphorylated RNAP II clusters at the peripheries of replication centers. Roscovitine treatment leads to decreased levels of hyperphosphorylated RNAP II (RNAP IIo) in infected cells and of hypophosphorylated RNAP II in mock-infected and infected cells. The RNAP IIo decrease does not occur if roscovitine is added 8 h postinfection, as was previously observed for processing of IE transcripts. These results suggest that accurate IE gene expression requires specific phosphorylation of the RNAP II CTD early in infection.
Human Cytomegalovirus UL97 Kinase Is Required for the Normal Intranuclear Distribution of pp65 and Virion Morphogenesis
Authors: Prichard Mark N. , Britt William J. , Daily Shannon L. , Hartline Caroll B. , Kern Earl R.
Published: November 2005

Recombinant human cytomegaloviruses that do not express UL97 kinase activity exhibit a distinctive plaque morphology characterized by the formation of highly refractile bodies late in infection. These structures were also observed in infected cells treated with the UL97 kinase inhibitor maribavir. Nuclear inclusions were purified to near homogeneity, and the constituent proteins were identified by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. This analysis demonstrated that the aggregates were formed principally of the tegument proteins pp65 and ppUL25 but also contained additional virion structural proteins including the major capsid protein. Immunoblotting experiments confirmed these results and identified a number of additional viral proteins present in the purified tegument aggregates. Interestingly, the formation of these structures appeared to be dependent on pp65, since it was not induced in cells infected with a recombinant virus with this open reading frame deleted. Morphologically similar aggregates could be reproduced in nuclei of uninfected cells by overexpressing pp65, and their formation was prevented by coexpressing the UL97 kinase. Inhibition of UL97 kinase activity with maribavir or mutation of an essential amino acid in the kinase abolished its ability to prevent aggregate formation. These data taken together suggest that the UL97 kinase impacts the aggregation of pp65 in the nuclei of infected cells. We propose that the kinase plays an important role in the acquisition of tegument during virion morphogenesis in the nucleus and that this activity represents an important step in the production of mature virus particles.
Signal Peptide Cleavage and Internal Targeting Signals Direct the Hepatitis C Virus p7 Protein to Distinct Intracellular Membranes
Authors: Griffin Stephen , Clarke Dean , McCormick Christopher , Rowlands David , Harris Mark
Published: November 2005

The hepatitis C virus (HCV) p7 protein forms an amantadine-sensitive ion channel required for viral replication in chimpanzees, though its precise role in the life cycle of HCV is unknown. In an attempt to gain some insights into p7 function, we examined the intracellular localization of p7 using epitope tags and an anti-p7 peptide antibody, antibody 1055. Immunofluorescence labeling of p7 at its C terminus revealed an endoplasmic reticulum (ER) localization independent of the presence of its signal peptide, whereas labeling the N terminus gave a mitochondrial-type distribution in brightly labeled cells. Both of these patterns could be visualized within individual cells, suggestive of separate pools of p7 where the N and C termini differed in accessibility to antibody. These patterns were disrupted by preventing signal peptide cleavage. Subcellular fractionation revealed that p7 was enriched in a heavy membrane fraction associated with mitochondria as well as normal ER-derived microsomes. The complex regulation of the intracellular distribution of p7 suggests that p7 plays multiple roles in the HCV life cycle either intracellularly or as a virion component.
The C Terminus of the Nucleoprotein of Influenza A Virus Delivers Antigens Transduced by Tat to thetrans-Golgi Network and Promotes an Efficient Presentation through HLA Class I
Authors: Bettosini Francesca , Fiorillo Maria Teresa , Magnacca Adriana , Leone Laura , Torrisi Maria Rosaria , Sorrentino Rosa
Published: November 2005

Cytotoxic T lymphocytes (CTLs) are the most powerful weapon of the immune system to eliminate cells infected by intracellular parasites or tumors. However, very often, escape mechanisms overcome CTL immune surveillance by impairing the classical HLA class I antigen-processing pathway. Here, we describe a strategy for CTL activation based on the ability of Tat to mediate transcellular delivery of viral proteins encompassing HLA class I-restricted epitopes. In this system, the recombinant protein TAT-NpFlu containing the transduction domain of Tat of human immunodeficiency virus type 1 fused to the amino acid region 301 to 498 of the nucleoprotein of influenza A virus is proven to sensitize different human cells to lysis by HLA-B27-restricted, Flu 383-391-specific CTL lines. The fusion protein is processed very effectively, since a comparable biological effect is obtained with an amount of protein between 1 and 2 orders of magnitude lower than that of the synthetic peptide. Interestingly, while part of TAT-NpFlu undergoes fast and productive cleavage, a large amount of it remains intact for up to 24 h. Confocal microscopy shows that TAT-NpFlu accumulates in thetrans-Golgi network (TGN), where it starts to be detectable 1 h after transduction. Using TAT-NpFlu mutants and hybrid constructs, we demonstrate that enrichment in the TGN occurs only when the carboxy-terminal region of NpFlu (amino acids 400 to 498) is present. These data disclose an unconventional route for presentation of epitopes restricted for HLA class I molecules.
A Deubiquitinating Activity Is Conserved in the Large Tegument Protein of the
Herpesviridae
Authors: Schlieker Christian , Korbel Gregory A. , Kattenhorn Lisa M. , Ploegh Hidde L.
Published: November 2005

The largest tegument protein of herpes simplex virus 1 (HSV-1), UL36, contains a novel deubiquitinating activity embedded in it. All members of the
Herpesviridae
contain a homologue of HSV-1 UL36, the N-terminal segments of which show perfect conservation of those residues implicated in catalysis. For murine cytomegalovirus and Epstein-Barr virus, chosen as representatives of the beta- and gammaherpesvirus subfamilies, respectively, we here show that the homologous modules indeed display deubiquitinating activity in vitro. The conservation of this activity throughout all subfamilies is indicative of an important, if not essential, function.
Matrix-Induced Inhibition of Membrane Binding Contributes to Human Immunodeficiency Virus Type 1 Particle Assembly Defects in Murine Cells
Authors: Hatziioannou Theodora , Martin-Serrano Juan , Zang Trinity , Bieniasz Paul D.
Published: November 2005

Defective human immunodeficiency virus type 1 (HIV-1) assembly in murine cells is accompanied by poor plasma membrane binding and proteolytic processing of the HIV-1 Gag precursor. Here, we show that such defects are induced by the propensity of the HIV-1 MA globular head to inhibit membrane binding and particle assembly, particularly at the low expression levels observed in murine cells. Simple additions to or deletion of the MA globular head can improve the yield of infectious virions from murine cells by >50-fold. Expression level and autoinhibition can be important confounding variables in studies of HIV-1 assembly and contribute to defects encountered in murine cells.
Stress fractures of the femoral shaft in women’s college lacrosse: a report of seven cases and a review of the literature
Authors: Kang L , Belcher D , Hulstyn M J
Published: November 2005

Background:Stress fractures do not often occur in the shaft of the femur. They are more common in the femoral neck, the tibial shaft, the metatarsals, and other bones of the foot. In female athletes, stress fractures classically afflict the distance runner, the ballerina, the gymnast, and the figure skater.

Objectives:To describe the clinical presentation, diagnosis, treatment, and outcome of seven college female lacrosse players with femoral shaft stress fractures, and review the literature.

Results:The unusual results of this study support the principle that clinical suspicion should be high when treating any female athlete regardless of the sport. In this case series, an abrupt change in the quality of the running surface during the competitive training season was the only underlying common thread among the athletes.

Conclusion:The findings suggest that risk factors for the female athlete are variable and are no longer limited to the undernourished or overtrained.
Evidence for secular trends in children’s physical activity behaviour
Authors: Dollman J , Norton K , Norton L
Published: November 2005

It is not clear whether the global increase in weight problems in children is the result of excessive energy intake or decreasing energy expenditure. Methodological limitations have made it difficult to analyse. There is evidence that at least part of the problem may lie with increasing energy consumption, but it is important to examine the other side of the energy equation also. However, it is not possible to conclusively describe physical activity trends because of the absence of suitable baseline data. One solution is to summate all available evidence in as many areas of daily activities as possible and then draw tentative conclusions. This review summarises available trend data on direct representations of physical activity in a range of contexts, together with indirect measures such as sedentariness, fitness, and attitudes. The conclusions drawn are: physical activity in clearly defined contexts such as active transport, school physical education, and organised sports is declining in many countries; young people would like to be active but are often constrained by external factors such as school policy or curricula, parental rules in relation to safety and convenience, and physical environmental factors.
Effects of inhaled bronchodilators and corticosteroids on exercise induced arterial hypoxaemia in trained male athletes
Authors: Hodges A N H , Lynn B M , Koehle M S , McKenzie D C
Published: November 2005

Objectives:To determine the effect of prophylactic treatment with an inhaled bronchodilator and anti-inflammatory on arterial saturation (Sao2) in trained non-asthmatic male athletes with exercise induced arterial hypoxaemia (EIAH).

Methods:Nine male athletes (mean (SD) age 26.3 (6.7) years, height 182.6 (7.9) cm, weight 79.3 (10.5) kg, Vo2max62.3 (6.3) ml/kg/min, Sao2min92.5 (1.1)%) with no history of asthma were tested in two experimental conditions. A combination of a therapeutic dose of salbutamol and fluticasone or an inert placebo was administered in a randomised crossover design for seven days before maximal cycling exercise. Oxygen consumption (Vo2), ventilation (Ve), heart rate (HR), power output, and Sao2were monitored during the exercise tests.

Results:There were no significant differences between the drug (D) and placebo (P) conditions for minimal Sao2(D  =  93.6 (1.4), P  =  93.0 (1.1)%; p  =  0.93) Vo2max(D  =  61.5 (7.2), P  =  61.9 (6.3) ml/kg/min; p  =  0.91), peak power (D  =  444.4 (48.3), P  =  449.4 (43.9) W; p  =  0.90), peak Ve(D  =  147.8 (19.1), P  =  149.2 (15.5) litres/min; p  =  0.82), or peak heart rate (D  =  182.3 (10.0), P  =  180.8 (5.5) beats/min; p  =  0.76).

Conclusions:A therapeutic dose of salbutamol and fluticasone did not attenuate EIAH during maximal cycling in a group of trained male non-asthmatic athletes.
Yoga for anxiety: a systematic review of the research evidence
Authors: Kirkwood G , Rampes H , Tuffrey V , Richardson J , Pilkington K
Published: November 2005

Between March and June 2004, a systematic review was carried out of the research evidence on the effectiveness of yoga for the treatment of anxiety and anxiety disorders. Eight studies were reviewed. They reported positive results, although there were many methodological inadequacies. Owing to the diversity of conditions treated and poor quality of most of the studies, it is not possible to say that yoga is effective in treating anxiety or anxiety disorders in general. However, there are encouraging results, particularly with obsessive compulsive disorder. Further well conducted research is necessary which may be most productive if focused on specific anxiety disorders.
Specific incremental test in elite squash players
Authors: Girard O , Sciberras P , Habrard M , Hot P , Chevalier R , Millet G P
Published: November 2005

Objectives:To compare cardiorespiratory responses between incremental treadmill (non-specific) and field (sport specific) tests in elite squash players.

Methods:Seven elite players (ranked 1 to 25 in their national federation including the World number 1) randomly performed an incremental treadmill test (TT) and a squash specific graded test (ST) to exhaustion. The ST consisted of repeated displacements replicating the game of squash, at increasing speed on the court. In both tests, ventilatory variables and heart rate were determined at the ventilatory threshold, respiratory compensation point, and maximal loads (max).

Results:Heart rate and percentage maximal oxygen uptake (V˙o2max) at the ventilatory threshold and respiratory compensation point were not different between the ST and TT, whereas V˙o2maxwas higher in the ST than in the TT (63.6 (3.0)v54.9 (2.5) ml/kg/min; p<0.001). Time to exhaustion was not different between the ST and TT (1056 (180)v962 (71) seconds) but correlated with the ranking of the players only in the ST (r =  −0.96, p<0.001).

Conclusions:V˙o2maxvalues derived from laboratory testing were not relevant for accurately estimating fitness in elite squash players. So the ST may be used as an additional test for determination of training intensity. Improved training advice for prescribing aerobic exercise or perfecting stroke technique may result from these results.
Physiological characteristics of top level off-road motorcyclists
Authors: Gobbi A W , Francisco R A , Tuy B , Kvitne R S
Published: November 2005

Objectives:The study aims to analyse the physiological characteristics of top level off-road motocross, enduro, and desert rally motorcyclists to facilitate the design of a specific training program.

Methods:Twenty seven off-road top level riders participated in this study which measured anthropometric data, maximum aerobic power with incremental tests of both arms and legs, isokinetic dynamometry of the knee and elbow, handgrip strength, heart rate, and blood lactate concentrations during competition.

Results:The physical demands of the various races appear to influence the development of distinct musculoskeletal characteristics, as well as aerobic and anaerobic metabolism. Motocross riders have more muscle mass, higher isokinetic handgrip strength, and greater aerobic power than enduro and desert rally riders. However, there are no significant anthropometric and physiological differences between desert rally and enduro riders. Desert rally riders tend to be overweight with maximum aerobic power similar to that of healthy individuals. The mechanical characteristics of the motorcycle and the technical and tactical skills of the riders seem to be more important for race success than the metabolic capabilities of the rider.

Conclusions:Desert rally and enduro riders present similar anthropometric and physiological characteristics. Both have a maximum aerobic power similar to that of healthy normal individuals, although desert rally riders tend to be overweight. Motocross riders on the other hand, have more muscle mass, more strength, and greater aerobic power. The differences observed suggest the need for a specific training program to address the requirements of different riders to reduce the possibility of injury.