bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Amino Acid Substitutions Supporting Antigenic Change of Influenza A(H1N1)pdm09 Viruses
Authors: Koel Björn F. , Mögling Ramona , Chutinimitkul Salin , Fraaij Pieter L. , Burke David F. , van der Vliet Stefan , de Wit Emmie , Bestebroer Theo M. , Rimmelzwaan Guus F. , Osterhaus Albert D. M. E. , Smith Derek J. , Fouchier Ron A. M. , de Graaf Miranda 
Published: January 2015

ABSTRACTThe majority of currently circulating influenza A(H1N1) viruses are antigenically similar to the virus that caused the 2009 influenza pandemic. However, antigenic variants are expected to emerge as population immunity increases. Amino acid substitutions in the hemagglutinin protein can result in escape from neutralizing antibodies, affect viral fitness, and change receptor preference. In this study, we constructed mutants with substitutions in the hemagglutinin of A/Netherlands/602/09 in an attenuated backbone to explore amino acid changes that may contribute to emergence of antigenic variants in the human population. Our analysis revealed that single substitutions affecting the loop that consists of amino acid positions 151 to 159 located adjacent to the receptor binding site caused escape from ferret and human antibodies elicited after primary A(H1N1)pdm09 virus infection. The majority of these substitutions resulted in similar or increased replication efficiencyin vitrocompared to that of the virus carrying the wild-type hemagglutinin and did not result in a change of receptor preference. However, none of the substitutions was sufficient for escape from the antibodies in sera from individuals that experienced both seasonal and pandemic A(H1N1) virus infections. These results suggest that antibodies directed against epitopes on seasonal A(H1N1) viruses contribute to neutralization of A(H1N1)pdm09 antigenic variants, thereby limiting the number of possible substitutions that could lead to escape from population immunity.IMPORTANCEInfluenza A viruses can cause significant morbidity and mortality in humans. Amino acid substitutions in the hemagglutinin protein can result in escape from antibody-mediated neutralization. This allows the virus to reinfect individuals that have acquired immunity to previously circulating strains through infection or vaccination. To date, the vast majority of A(H1N1)pdm09 strains remain antigenically similar to the virus that caused the 2009 influenza pandemic. However, antigenic variants are expected to emerge as a result of increasing population immunity. We show that single amino acid substitutions near the receptor binding site were sufficient to escape from antibodies specific for A(H1N1)pdm09 viruses but not from antibodies elicited in response to infections with seasonal A(H1N1) and A(H1N1)pdm09 viruses. This study identified substitutions in A(H1N1)pdm09 viruses that support escape from population immunity but also suggested that the number of potential escape variants is limited by previous exposure to seasonal A(H1N1) viruses.
Control of Hepatitis C Virus Replication in Mouse Liver-Derived Cells by MAVS-Dependent Production of Type I and Type III Interferons
Authors: Anggakusuma  , Frentzen Anne , Gürlevik Engin , Yuan Qinggong , Steinmann Eike , Ott Michael , Staeheli Peter , Schmid-Burgk Jonathan , Schmidt Tobias , Hornung Veit , Kuehnel Florian , Pietschmann Thomas 
Published: January 2015

ABSTRACTHepatitis C virus (HCV) efficiently infects only humans and chimpanzees. Although the detailed mechanisms responsible for this narrow species tropism remain elusive, recent evidence has shown that murine innate immune responses efficiently suppress HCV replication. Therefore, poor adaptation of HCV to evade and/or counteract innate immune responses may prevent HCV replication in mice. The HCV NS3-4A protease cleaves human MAVS, a key cellular adaptor protein required for RIG-I-like receptor (RLR)-dependent innate immune signaling. However, it is unclear if HCV interferes with mouse MAVS function equally well. Moreover, MAVS-dependent signaling events that restrict HCV replication in mouse cells were incompletely defined. Thus, we quantified the ability of HCV NS3-4A to counteract mouse and human MAVS. HCV NS3-4A similarly diminished both human and mouse MAVS-dependent signaling in human and mouse cells. Moreover, replicon-encoded protease cleaved a similar fraction of both MAVS variants. Finally, FLAG-tagged MAVS proteins repressed HCV replication to similar degrees. Depending on MAVS expression, HCV replication in mouse liver cells triggered not only type I but also type III IFNs, which cooperatively repressed HCV replication. Mouse liver cells lacking both type I and III IFN receptors were refractory to MAVS-dependent antiviral effects, indicating that the HCV-induced MAVS-dependent antiviral state depends on both type I and III IFN receptor signaling.IMPORTANCEIn this study, we found that HCV NS3-4A similarly diminished both human and mouse MAVS-dependent signaling in human and mouse cells. Therefore, it is unlikely that ineffective cleavage of mouse MAVSper seprecludes HCV propagation in immunocompetent mouse liver cells. Hence, approaches to reinforce HCV replication in mouse liver cells (e.g., by expression of essential human replication cofactors) should not be thwarted by the poor ability of HCV to counteract MAVS-dependent antiviral signaling. In addition, we show that mouse MAVS induces both type I and type III IFNs, which together control HCV replication. Characterization of type I or type III-dependent interferon-stimulated genes in these cells should help to identify key murine restriction factors that preclude HCV propagation in immunocompetent mouse liver cells.
Severe Acute Respiratory Syndrome Coronaviruses with Mutations in the E Protein Are Attenuated and Promising Vaccine Candidates
Authors: Regla-Nava Jose A. , Nieto-Torres Jose L. , Jimenez-Guardeño Jose M. , Fernandez-Delgado Raul , Fett Craig , Castaño-Rodríguez Carlos , Perlman Stanley , Enjuanes Luis , DeDiego Marta L. 
Published: January 2015

ABSTRACTSevere acute respiratory syndrome coronavirus (SARS-CoV) causes a respiratory disease with a mortality rate of 10%. A mouse-adapted SARS-CoV (SARS-CoV-MA15) lacking the envelope (E) protein (rSARS-CoV-MA15-ΔE) is attenuatedin vivo. To identify E protein regions and host responses that contribute to rSARS-CoV-MA15-ΔE attenuation, several mutants (rSARS-CoV-MA15-E*) containing point mutations or deletions in the amino-terminal or the carboxy-terminal regions of the E protein were generated. Amino acid substitutions in the amino terminus, or deletion of regions in the internal carboxy-terminal region of E protein, led to virus attenuation. Attenuated viruses induced minimal lung injury, diminished limited neutrophil influx, and increased CD4+and CD8+T cell counts in the lungs of BALB/c mice, compared to mice infected with the wild-type virus. To analyze the host responses leading to rSARS-CoV-MA15-E* attenuation, differences in gene expression elicited by the native and mutant viruses in the lungs of infected mice were determined. Expression levels of a large number of proinflammatory cytokines associated with lung injury were reduced in the lungs of rSARS-CoV-MA15-E*-infected mice, whereas the levels of anti-inflammatory cytokines were increased, both at the mRNA and protein levels. These results suggested that the reduction in lung inflammation together with a more robust antiviral T cell response contributed to rSARS-CoV-MA15-E* attenuation. The attenuated viruses completely protected mice against challenge with the lethal parental virus, indicating that these viruses are promising vaccine candidates.IMPORTANCEHuman coronaviruses are important zoonotic pathogens. SARS-CoV caused a worldwide epidemic infecting more than 8,000 people with a mortality of around 10%. Therefore, understanding the virulence mechanisms of this pathogen and developing efficacious vaccines are of high importance to prevent epidemics from this and other human coronaviruses. Previously, we demonstrated that a SARS-CoV lacking the E protein was attenuatedin vivo. Here, we show that small deletions and modifications within the E protein led to virus attenuation, manifested by minimal lung injury, limited neutrophil influx to the lungs, reduced expression of proinflammatory cytokines, increased anti-inflammatory cytokine levels, and enhanced CD4+and CD8+T cell countsin vivo, suggesting that these phenomena contribute to virus attenuation. The attenuated mutants fully protected mice from challenge with virulent virus. These studies show that mutations in the E protein are not well tolerated and indicate that this protein is an excellent target for vaccine development.
High Secretion of Interferons by Human Plasmacytoid Dendritic Cells upon Recognition of Middle East Respiratory Syndrome Coronavirus
Authors: Scheuplein Vivian A. , Seifried Janna , Malczyk Anna H. , Miller Lilija , Höcker Lena , Vergara-Alert Júlia , Dolnik Olga , Zielecki Florian , Becker Björn , Spreitzer Ingo , König Renate , Becker Stephan , Waibler Zoe , Mühlebach Michael D. 
Published: January 2015

ABSTRACTThe Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012 as the causative agent of a severe respiratory disease with a fatality rate of approximately 30%. The high virulence and mortality rate prompted us to analyze aspects of MERS-CoV pathogenesis, especially its interaction with innate immune cells such as antigen-presenting cells (APCs). Particularly, we analyzed secretion of type I and type III interferons (IFNs) by APCs, i.e., B cells, macrophages, monocyte-derived/myeloid dendritic cells (MDDCs/mDCs), and by plasmacytoid dendritic cells (pDCs) of human and murine origin after inoculation with MERS-CoV. Production of large amounts of type I and III IFNs was induced exclusively in human pDCs, which were significantly higher than IFN induction by severe acute respiratory syndrome (SARS)-CoV. Of note, IFNs were secreted in the absence of productive replication. However, receptor binding, endosomal uptake, and probably signaling via Toll-like receptor 7 (TLR7) were critical for sensing of MERS-CoV by pDCs. Furthermore, active transcription of MERS-CoV N RNA and subsequent N protein expression were evident in infected pDCs, indicating abortive infection. Taken together, our results point toward dipeptidyl peptidase 4 (DPP4)-dependent endosomal uptake and subsequent infection of human pDCs by MERS-CoV. However, the replication cycle is stopped after early gene expression. In parallel, human pDCs are potent IFN-producing cells upon MERS-CoV infection. Knowledge of such IFN responses supports our understanding of MERS-CoV pathogenesis and is critical for the choice of treatment options.IMPORTANCEMERS-CoV causes a severe respiratory disease with high fatality rates in human patients. Recently, confirmed human cases have increased dramatically in both number and geographic distribution. Understanding the pathogenesis of this highly pathogenic CoV is crucial for developing successful treatment strategies. This study elucidates the interaction of MERS-CoV with APCs and pDCs, particularly the induction of type I and III IFN secretion. Human pDCs are the immune cell population sensing MERS-CoV but secrete significantly larger amounts of IFNs, especially IFN-α, than in response to SARS-CoV. A model for molecular virus-host interactions is presented outlining IFN induction in pDCs. The massive IFN secretion upon contact suggests a critical role of this mechanism for the high degree of immune activation observed during MERS-CoV infection.
Simian Retrovirus 4 Induces Lethal Acute Thrombocytopenia in Japanese Macaques
Authors: Yoshikawa Rokusuke , Okamoto Munehiro , Sakaguchi Shoichi , Nakagawa So , Miura Tomoyuki , Hirai Hirohisa , Miyazawa Takayuki 
Published: January 2015

ABSTRACT

In 2001-2002, six of seven Japanese macaques (
Macaca fuscata
) died after developing hemorrhagic syndrome at the Kyoto University Primate Research Institute (KUPRI). While the cause of death was unknown at the time, we detected simian retrovirus 4 (SRV-4) in samples obtained from a similar outbreak in 2008-2011, during which 42 of 43 Japanese macaques died after exhibiting hemorrhagic syndrome. In this study, we isolated SRV-4 strain PRI-172 from a Japanese macaque showing severe thrombocytopenia. When inoculated into four Japanese macaques, the isolate induced severe thrombocytopenia in all within 37 days. We then constructed an infectious molecular clone of strain PRI-172, termed pSR415, and inoculated the clone-derived virus into two Japanese macaques. These animals also developed severe thrombocytopenia in just 31 days after inoculation, and the virus was reisolated from blood, bone marrow, and stool. At necropsy, we observed bleeding from the gingivae and subcutaneous bleeding in all animals. SRV-4 infected a variety of tissues, especially in digestive organs, including colon and stomach, as determined by real-time reverse transcription-PCR (RT-PCR) and immunohistochemical staining. Furthermore, we identified the SRV-4 receptor as ASCT2, a neutral amino acid transporter. ASCT2 mRNA was expressed in a variety of tissues, and the distribution of SRV-4 proviruses in infected Japanese macaques correlated well with the expression levels of ASCT2 mRNA. From these results, we conclude that the causative agent of hemorrhagic syndrome in KUPRI Japanese macaques was SRV-4, and its receptor is ASCT2.

IMPORTANCE
During two separate outbreaks at the KUPRI, in 2001-2002 and 2008-2011, 96% of Japanese macaques (JM) that developed an unknown hemorrhagic syndrome died. Here, we isolated SRV-4 from a JM developing thrombocytopenia. The SRV-4 isolate and a molecularly cloned SRV-4 induced severe thrombocytopenia in virus-inoculated JMs within 37 days. At necropsy, we observed bleeding from gingivae and subcutaneous bleeding in all affected JMs and reisolated SRV-4 from blood, bone marrow, and stool. The distribution of SRV-4 proviruses in tissues correlated with the mRNA expression levels of ASCT2, which we identified as the SRV-4 receptor. From these results, we conclude that SRV-4 was the causative agent of hemorrhagic syndrome in JMs in KUPRI.
Increase in the oxidised low-density lipoprotein level by smoking and the possible inhibitory effect of statin therapy in patients with cardiovascular disease: a retrospective study
Authors: Ogawa Kazuo , Tanaka Toshikazu , Nagoshi Tomohisa , Sekiyama Hiroshi , Arase Satoshi , Minai Kosuke , Ogawa Takayuki , Yoshimura Michihiro 
Published: January 2015

ObjectivesMalondialdehyde-modified low-density lipoprotein (MDA-LDL) level is a marker of oxidative stress and is linked to progression of arteriosclerosis; however, the clinical factors affecting the oxidised LDL level have not been elucidated. We investigate various factors to identify correlation with MDA-LDL level in high-risk patients requiring catheter intervention.SettingSecondary care (cardiology), single-centre study.Participants600 patients who were admitted to our hospital and underwent cardiac catheterisation.Primary and secondary outcome measuresBlood samples were obtained to measure lipid profiles and MDA-LDL level.ResultsWith regard to smoking status, MDA-LDL level was significantly higher in ex-smokers/current smokers compared with non-smokers. Of note, there was no improvement of MDA-LDL level even in patients who had quit smoking. Multiple regression analysis showed that MDA-LDL level was positively correlated with LDL-cholesterol (LDL-C) level, Brinkman index and male gender. The correlation between smoking status and either MDA-LDL or LDL-C level was investigated in two groups: namely, patients with and patients without statin treatment. In the non-statin group, MDA-LDL level and MDA-LDL/LDL-C ratio were significantly higher in ex-smokers/current smokers compared with non-smokers, while no significant correlation was observed between smoking status and LDL-C level. In contrast, in the statin group, there were no significant correlations between smoking status and any of the cholesterol parameters.ConclusionsWe found that MDA-LDL level was affected by multiple factors, such as smoking status, LDL-C level and male gender. The present findings give additional evidence that smoking should be prohibited from a MDA-LDL standpoint. Furthermore, statin therapy might have a beneficial effect on the reduction of MDA-LDL level.
Confusion: delirium and dementia - a smartphone app to improve cognitive assessment
Authors: Sangha Selina , George J , Winthrop Craig , Panchal Sonia 
Published: January 2015

AbstractOlder patients with dementia and delirium are more prone to adverse events in hospital, but formal cognitive assessment to identify these vulnerable patients on admission is often not carried out by junior doctors. A smartphone app was created and provided on hospital wards to facilitate the use of standard cognitive assessments for delirium and dementia. Before the introduction of the app, 36% of patients over 75 years old were assessed cognitively. After the app, the percentage of cognitive assessments improved to 63%. Improvements in cognitive assessments were most marked after individual teaching of the doctors on the wards in the use of the app and on making the app available on the ward tablets. The results of the study suggest that the introduction of a smartphone app for junior doctors can improve performance in cognitive assessment of older people.
How unique is pure erythroid leukaemia? A retrospective analysis of seven cases and review of the literature
Authors: Wong Eric , Ling Victoria , Westerman David , Morgan Susan , Juneja Surender 
Published: January 2015

AimsPure erythroid leukaemia (PEL) is a rare subtype of acute myeloid leukaemia (AML) and its clinicopathological features are not well-defined. The aim of this study was to describe the immunophenotypic, cytogenetic and clinical features of PEL and to compare these with cases of AML with ≥50% erythroblasts.MethodsCases of PEL according to WHO morphological criteria diagnosed at three institutions from 1997 to 2013 were included. A comparison cohort comprised of AML with ≥50% erythroblasts. The clinical, histopathology, immunophenotypic and cytogenetic features of cases were analysed. We also reviewed the existing literature on PEL, and combined our cohort with previously reported cases of PEL in a pooled analysis.ResultsThere were seven cases of PEL diagnosed at our institutions. There was a high incidence of either prior chemoradiotherapy exposure or evolution from pre-existing myelodysplastic syndrome (MDS) (71%). The leukaemic blasts frequently expressed glycophorin C (100%), CD117 (83%) and were myeloperoxidase negative (83%). Complex karyotypes were present in 83% of cases. Median overall survival was 2.9 months. Compared with AML with ≥50% erythroblasts, cases of PEL demonstrated a higher incidence of adverse-risk cytogenetics (p=0.01) and prior exposure to chemoradiotherapy (p=0.01).ConclusionsPEL appears to be a unique entity that is often secondary or therapy related, commonly features a complex karyotype and has a poor prognosis. It is morphologically and immunophenotypically distinct from other cases of AML with erythroid hyperplasia.
Genetic and Pharmacologic Inhibition of eIF4E Reduces Breast Cancer Cell Migration, Invasion, and Metastasis
Authors: Pettersson Filippa , del Rincon Sonia V. , Emond Audrey , Huor Bonnie , Ngan Elaine , Ng Jonathan , Dobocan Monica C. , Siegel Peter M. , Miller Wilson H. 
Published: January 2015

Abstract
The translation initiation factor eIF4E is an oncogene that is commonly overexpressed in primary breast cancers and metastases. In this article, we report that a pharmacologic inhibitor of eIF4E function, ribavirin, safely and potently suppresses breast tumor formation. Ribavirin administration blocked the growth of primary breast tumors in several murine models and reduced the development of lung metastases in an invasive model. Mechanistically, eIF4E silencing or blockade reduced the invasiveness and metastatic capability of breast cancer cells in a manner associated with decreased activity of matrix metalloproteinase (MMP)-3 and MMP-9. Furthermore, eIF4E silencing or ribavirin treatment suppressed features of epithelial-to-mesenchymal transition, a process crucial for metastasis. Our findings offer a preclinical rationale to explore broadening the clinical evaluation of ribavirin, currently being tested in patients with eIF4E-overexpressing leukemia, as a strategy to treat solid tumors such as metastatic breast cancer. Cancer Res; 75(6); 1102–12. ©2015 AACR.
Trabectedin Efficacy in Ewing Sarcoma Is Greatly Increased by Combination with Anti-IGF Signaling Agents
Authors: Amaral Ana Teresa , Garofalo Cecilia , Frapolli Roberta , Manara Maria Cristina , Mancarella Caterina , Uboldi Sarah , Giandomenico Silvana Di , Ordóñez Jose Luis , Sevillano Victoria , Malaguarnera Roberta , Picci Piero , Hassan A. Bass , Alava Enrique De , D'Incalci Maurizio , Scotlandi Katia 
Published: January 2015

Abstract
Purpose: Goal of this study was to identify mechanisms that limit efficacy of trabectedin (ET-743, Yondelis) in Ewing sarcoma (EWS), so as to develop a clinical applicable combination therapy.
Experimental Design: By chromatin immunoprecipitation, we analyzed EWS–FLI1 binding to the promoters of several target genes, such as TGFβR2, CD99, insulin-like growth factor receptor 1 (IGF1R), and IGF1, both in vitro and in xenografts treated with trabectedin or doxorubicin. Combined therapy with trabectedin and anti-IGF1R agents (AVE1642 HAb; OSI-906) was tested in vitro and in xenografts.
Results: We confirm that both trabectedin and doxorubicin were able to strongly reduce EWS–FLI1 (both type I and type II) binding to two representative target genes (TGFβR2 and CD99), both in vitro and in xenografts. However, trabectedin, but not doxorubicin, was also able to increase the occupancy of EWS–FLI1 to IGF1R promoters, leading to IGF1R upregulation. Inhibition of IGF1R either by the specific AVE1642 human antibody or by the dual IGF1R/insulin receptor inhibitor OSI-906 (Linsitinib) greatly potentiate the efficacy of trabectedin in the 13 EWS cell lines here considered as well as in TC-71 and 6647 xenografts. Combined therapy induced synergistic cytotoxic effects. Trabectedin and OSI-906 deliver complementary messages that likely converge on DNA-damage response and repair pathways.
Conclusions: We showed that trabectedin may not only inhibit but also enhance the binding of EWS–FLI1 to certain target genes, leading to upregulation of IGF1R. We here provide the rationale for combining trabectedin to anti-IGF1R inhibitors. Clin Cancer Res; 21(6); 1373–82. ©2015 AACR.