bluuebunny/crossref_metadata_2025_split huggingface dataset:
The N Terminus of Andes Virus L Protein Suppresses mRNA and Protein Expression in Mammalian Cells
Authors: Heinemann Patrick , Schmidt-Chanasit Jonas , Günther Stephan 
Published: April 2013

ABSTRACT
Little is known about the structure and function of the 250-kDa L protein of hantaviruses, although it plays a central role in virus genome transcription and replication. When attempting to study Andes virus (ANDV) L protein in mammalian cells, we encountered difficulties. Even in a strong overexpression system, ANDV L protein could not be detected by immunoblotting. Deletion analysis revealed that the 534 N-terminal amino acid residues determine the low-expression phenotype. Inhibition of translation due to RNA secondary structures around the start codon, rapid proteasomal degradation, and reduced half-life time were excluded. However, ANDV L protein expression could be rescued upon mutation of the catalytic PD-E-K motif and further conserved residues of the putative endonuclease at the N terminus of the protein. In addition, wild-type ANDV L rather than expressible L mutants suppressed the level of L mRNA, as well as reporter mRNAs. Wild-type L protein also reduced the synthesis of cellular proteins in the high-molecular-weight range. Using expressible ANDV L mutants as a tool for localization studies, we show that L protein colocalizes with ANDV N and NSs but not Gc protein. A fraction of L protein also colocalized with the cellular processing (P) body component DCP1a. Overall, these data suggest that ANDV L protein possesses a highly active endonuclease at the N terminus suppressing the level of its own as well as heterologous mRNAs upon recombinant expression in mammalian cells.
Chimeric Hemagglutinin Influenza Virus Vaccine Constructs Elicit Broadly Protective Stalk-Specific Antibodies
Authors: Krammer Florian , Pica Natalie , Hai Rong , Margine Irina , Palese Peter 
Published: April 2013

ABSTRACT

Current influenza virus vaccine strategies stimulate immune responses toward the globular head domain of the hemagglutinin protein in order to inhibit key steps of the virus life cycle. Because this domain is highly variable across strains, new vaccine formulations are required in most years. Here we demonstrate a novel vaccine strategy that generates immunity to the highly conserved stalk domain by using chimeric hemagglutinin constructs that express unique head and stalk combinations. By repeatedly immunizing mice with constructs that expressed the same stalk but an irrelevant head, we specifically stimulated a stalk-directed response that provided broad-based heterologous and heterosubtypic immunity in mice. Notably, our vaccination scheme provides a universal vaccine approach that protects against challenge with an H5 subtype virus. Furthermore, through
in vivo
studies using passively transferred antibodies or depletion of CD8
+
T cells, we demonstrated the critical role that humoral mechanisms of immunity play in the protection observed. The present data suggest that a vaccine strategy based on the stalk domain of the hemagglutinin protein could be used in humans to broadly protect against a variety of influenza virus subtypes.
Structure of Severe Fever with Thrombocytopenia Syndrome Virus Nucleocapsid Protein in Complex with Suramin Reveals Therapeutic Potential
Authors: Jiao Lianying , Ouyang Songying , Liang Mifang , Niu Fengfeng , Shaw Neil , Wu Wei , Ding Wei , Jin Cong , Peng Yao , Zhu Yanping , Zhang Fushun , Wang Tao , Li Chuan , Zuo Xiaobing , Luan Chi-Hao , Li Dexin , Liu Zhi-Jie 
Published: April 2013

ABSTRACT

Severe fever with thrombocytopenia syndrome is an emerging infectious disease caused by a novel bunyavirus (SFTSV). Lack of vaccines and inadequate therapeutic treatments have made the spread of the virus a global concern. Viral nucleocapsid protein (N) is essential for its transcription and replication. Here, we present the crystal structures of N from SFTSV and its homologs from Buenaventura (BUE) and Granada (GRA) viruses. The structures reveal that phleboviral N folds into a compact core domain and an extended N-terminal arm that mediates oligomerization, such as tetramer, pentamer, and hexamer of N assemblies. Structural superimposition indicates that phleboviral N adopts a conserved architecture and uses a similar RNA encapsidation strategy as that of RVFV-N. The RNA binding cavity runs along the inner edge of the ring-like assembly. A triple mutant of SFTSV-N, R64D/K67D/K74D, almost lost its ability to bind RNA
in vitro
, is deficient in its ability to transcribe and replicate. Structural studies of the mutant reveal that both alterations in quaternary assembly and the charge distribution contribute to the loss of RNA binding. In the screening of inhibitors Suramin was identified to bind phleboviral N specifically. The complex crystal structure of SFTSV-N with Suramin was refined to a 2.30-Å resolution. Suramin was found sitting in the putative RNA binding cavity of SFTSV-N. The inhibitory effect of Suramin on SFTSV replication was confirmed in Vero cells. Therefore, a common Suramin-based therapeutic approach targeting SFTSV-N and its homologs could be developed for containing phleboviral outbreaks.
Syndecan-1 Serves as the Major Receptor for Attachment of Hepatitis C Virus to the Surfaces of Hepatocytes
Authors: Shi Qing , Jiang Jieyun , Luo Guangxiang 
Published: April 2013

ABSTRACT
Our recent studies demonstrated that apolipoprotein E mediates cell attachment of hepatitis C virus (HCV) through interactions with the cell surface heparan sulfate (HS). HS is known to covalently attach to core proteins to form heparan sulfate proteoglycans (HSPGs) on the cell surface. The HSPG core proteins include the membrane-spanning syndecans (SDCs), the lycosylphosphatidylinositol-linked glypicans (GPCs), the basement membrane proteoglycan perlecan (HSPG2), and agrin. In the present study, we have profiled each of the HSPG core proteins in HCV attachment. Substantial evidence derived from our studies demonstrates that SDC1 is the major receptor protein for HCV attachment. The knockdown of SDC1 expression by small interfering RNA (siRNA)-induced gene silence resulted in a significant reduction of HCV attachment to Huh-7.5 cells and stem cell-differentiated human hepatocytes. The silence of SDC2 expression also caused a modest decrease of HCV attachment. In contrast, the siRNA-mediated knockdown of other SDCs, GPCs, HSPG2, and agrin had no effect on HCV attachment. More importantly, ectopic expression of SDC1 was able to completely restore HCV attachment to Huh-7.5 cells in which the endogenous SDC1 expression was silenced by specific siRNAs. Interestingly, mouse SDC1 is also fully functional in mediating HCV attachment when expressed in the SDC1-deficient cells, consistent with recent reports that mouse hepatocytes are also susceptible to HCV infection when expressing other key HCV receptors. Collectively, our findings demonstrate that SDC1 serves as the major receptor protein for HCV attachment to cells, providing another potential target for discovery and development of antiviral drugs against HCV.
Identification of doctors at risk of recurrent complaints: a national study of healthcare complaints in Australia
Authors: Bismark Marie M , Spittal Matthew J , Gurrin Lyle C , Ward Michael , Studdert David M 
Published: April 2013

Objectives(1) To determine the distribution of formal patient complaints across Australia's medical workforce and (2) to identify characteristics of doctors at high risk of incurring recurrent complaints.MethodsWe assembled a national sample of all 18 907 formal patient complaints filed against doctors with health service ombudsmen (‘Commissions’) in Australia over an 11-year period. We analysed the distribution of complaints among practicing doctors. We then used recurrent-event survival analysis to identify characteristics of doctors at high risk of recurrent complaints, and to estimate each individual doctor's risk of incurring future complaints.ResultsThe distribution of complaints among doctors was highly skewed: 3% of Australia's medical workforce accounted for 49% of complaints and 1% accounted for a quarter of complaints. Short-term risks of recurrence varied significantly among doctors: there was a strong dose-response relationship with number of previous complaints and significant differences by doctor specialty and sex. At the practitioner level, risks varied widely, from doctors with <10% risk of further complaints within 2 years to doctors with >80% risk.ConclusionsA small group of doctors accounts for half of all patient complaints lodged with Australian Commissions. It is feasible to predict which doctors are at high risk of incurring more complaints in the near future. Widespread use of this approach to identify high-risk doctors and target quality improvement efforts coupled with effective interventions, could help reduce adverse events and patient dissatisfaction in health systems.
Introduction of the i-gel supraglottic airway device for prehospital airway management in a UK ambulance service
Authors: Duckett Jay , Fell P , Han K , Kimber C , Taylor C 
Published: April 2013

AimTo clinically review the use of basic and advanced airway management techniques within the North East Ambulance Service National Health Service Foundation Trust (NEAS) for cardiac arrests following the introduction of the i-gel.MethodTwo retrospective clinical audits were carried out over a monthly period (May 2011 and January 2012) using electronic and paper NEAS patient records.ResultsThis audit confirmed that a range of basic and/or advanced airway management techniques are being successfully used to manage the airways of cardiac arrest patients. I-gel is emerging as a popular choice for maintaining and securing the airway during prehospital cardiopulmonary resuscitation. Success rates for i-gel insertion are higher (94%, 92%) than endotracheal (ET) tube insertion (90%, 86%). Documentation of the airway management method was poor in 11% of the records. The Quality Improvement Officers addressed this by providing individual feedback.ConclusionsI-gel shows a higher success rate in cardiac arrest patients compared to the ET tube. Staff who chose to use methods other than i-gel indicated this was a confidence issue when using new equipment. The re-audit indicated an upward trend in the popularity of i-gel; insertion is faster with a higher success rate, which allows the crew to progress with the other resuscitation measures more promptly. Airway soiling and aspiration beforehand have been reasons staff resort to ET intubation. It is anticipated by the authors that i-gel will emerge as the first choice of airway management device in prehospital cardiac arrests.
Which extended paramedic skills are making an impact in emergency care and can be related to the UK paramedic system? A systematic review of the literature
Authors: Evans Rachel , McGovern Ruth , Birch Jennifer , Newbury-Birch Dorothy 
Published: April 2013

BackgroundIncreasing demand on the UK emergency services is creating interest in reviewing the structure and content of ambulance services. Only 10% of emergency calls have been seen to be life-threatening and, thus, paramedics, as many patients’ first contact with the health service, have the potential to use their skills to reduce the demand on Emergency Departments. This systematic literature review aimed to identify evidence of paramedics trained with extra skills and the impact of this on patient care and interrelating services such as General Practices or Emergency Departments.MethodsInternational literature from Medline, Embase, Cumulative Index of Nursing and Allied Health Literature (CINAHL), ProQuest, Scopus and grey literature from 1990 were included. Articles about any prehospital emergency care provider trained with extra skill(s) beyond their baseline competencies and evaluated in practice were included. Specific procedures for certain conditions and the extensively evaluated UK Emergency Care Practitioner role were excluded.Results8724 articles were identified, of which 19 met the inclusion criteria. 14 articles considered paramedic patient assessment and management skills, two articles considered paramedic safeguarding skills, two health education and learning sharing and one health information. There is valuable evidence for paramedic assessing and managing patients autonomously to reduce Emergency Department conveyance which is acceptable to patients and carers. Evidence for other paramedic skills is less robust, reflecting a difficulty with rigorous research in prehospital emergency care.ConclusionsThis review identifies many viable extra skills for paramedics but the evidence is not strong enough to guide policy. The findings should be used to guide future research, particularly into paramedic care for elderly people.
Inhibition of c-Met Reduces Lymphatic Metastasis in RIP-Tag2 Transgenic Mice
Authors: Sennino Barbara , Ishiguro-Oonuma Toshina , Schriver Brian J. , Christensen James G. , McDonald Donald M. 
Published: April 2013

Abstract
Inhibition of VEGF signaling can promote lymph node metastasis in preclinical models, but the mechanism is not fully understood, and successful methods of prevention have not been found. Signaling of hepatocyte growth factor (HGF) and its receptor c-Met can promote the growth of lymphatics and metastasis of some tumors. We sought to explore the contributions of c-Met signaling to lymph node metastasis after inhibition of VEGF signaling. In particular, we examined whether c-Met is upregulated in lymphatics in or near pancreatic neuroendocrine tumors in RIP-Tag2 transgenic mice and whether lymph node metastasis can be reduced by concurrent inhibition of VEGF and c-Met signaling. Inhibition of VEGF signaling by anti-VEGF antibody or sunitinib in mice from the age of 14 to 17 weeks was accompanied by more intratumoral lymphatics, more tumor cells inside lymphatics, and more lymph node metastases. Under these conditions, lymphatic endothelial cells, like tumor cells, had strong immunoreactivity for c-Met and phospho-c-Met. c-Met blockade by the selective inhibitor, PF-04217903, significantly reduced metastasis to local lymph nodes. Together, these results indicate that inhibition of VEGF signaling in RIP-Tag2 mice upregulates c-Met expression in lymphatic endothelial cells, increases the number of intratumoral lymphatics and number of tumor cells within lymphatics, and promotes metastasis to local lymph nodes. Prevention of lymph node metastasis by PF-04217903 in this setting implicates c-Met signaling in tumor cell spread to lymph nodes. Cancer Res; 73(12); 3692–703. ©2013 AACR.
A Novel Model for Evaluating Therapies Targeting Human Tumor Vasculature and Human Cancer Stem–like Cells
Authors: Burgos-Ojeda Daniela , McLean Karen , Bai Shoumei , Pulaski Heather , Gong Yusong , Silva Ines , Skorecki Karl , Tzukerman Maty , Buckanovich Ronald J. 
Published: April 2013

Abstract
Human tumor vessels express tumor vascular markers (TVM), proteins that are not expressed in normal blood vessels. Antibodies targeting TVMs could act as potent therapeutics. Unfortunately, preclinical in vivo studies testing anti-human TVM therapies have been difficult to do due to a lack of in vivo models with confirmed expression of human TVMs. We therefore evaluated TVM expression in a human embryonic stem cell–derived teratoma (hESCT) tumor model previously shown to have human vessels. We now report that in the presence of tumor cells, hESCT tumor vessels express human TVMs. The addition of mouse embryonic fibroblasts and human tumor endothelial cells significantly increases the number of human tumor vessels. TVM induction is mostly tumor-type–specific with ovarian cancer cells inducing primarily ovarian TVMs, whereas breast cancer cells induce breast cancer specific TVMs. We show the use of this model to test an anti-human specific TVM immunotherapeutics; anti-human Thy1 TVM immunotherapy results in central tumor necrosis and a three-fold reduction in human tumor vascular density. Finally, we tested the ability of the hESCT model, with human tumor vascular niche, to enhance the engraftment rate of primary human ovarian cancer stem–like cells (CSC). ALDH+ CSC from patients (n = 6) engrafted in hESCT within 4 to 12 weeks whereas none engrafted in the flank. ALDH− ovarian cancer cells showed no engraftment in the hESCT or flank (n = 3). Thus, this model represents a useful tool to test anti-human TVM therapy and evaluate in vivo human CSC tumor biology. Cancer Res; 73(12); 3555–65. ©2013 AACR.
ING5 Is a Tip60 Cofactor That Acetylates p53 in Response to DNA Damage
Authors: Liu Nansong , Wang Jiadong , Wang Jifeng , Wang Rukai , Liu Zhongle , Yu Yao , Lu Hong 
Published: April 2013

Abstract
Posttranslational modification of p53 is a critical event in regulating the expression of its target genes. p53 is acetylated at lysine 120 (K120) by acetyltranferases Tip60 (KAT5) and hMOF (KAT8) in response to DNA damage. Identification of cofactors for these two enzymes will shed light on the mechanism by which cells make a choice between cell-cycle arrest and apoptosis. It has been reported that ING5, a member of the inhibitor of growth (ING) family, is involved in p53-dependent pathways, but its exact role is unknown. In this study, we found that ING5 expression was significantly increased and that ING5 assisted Tip60, but not hMOF, in acetylating p53 at K120 in response to DNA damage. ING5 had no effect on acetylation of p53 at K373/382, but it formed a complex with p53 and Tip60. ING5 was required for acetylation of p53 at K120, and p53 acetylated at K120 subsequently bound to the promoters of its target apoptotic genes, BAX and GADD45, to promote their expression and lead to apoptosis. Mutation of K120 to K120R abolished the effects of ING5 on p53-induced gene expression. Thus, we conclude that ING5 functions as a cofactor of Tip60 in the acetylation of p53 at K120 in response to DNA damage. Cancer Res; 73(12); 3749–60. ©2013 AACR.
Mathematical Modeling of Tumor Cell Proliferation Kinetics and Label Retention in a Mouse Model of Lung Cancer
Authors: Zheng Yanyan , Moore Helen , Piryatinska Alexandra , Solis Trinidad , Sweet-Cordero E. Alejandro 
Published: April 2013

Abstract
Slowly cycling tumor cells that may be present in human tumors may evade cytotoxic therapies, which tend to be more efficient at destroying cells with faster growth rates. However, the proportion and growth rate of slowly cycling tumor cells is often unknown in preclinical model systems used for drug discovery. Here, we report a quantitative approach to quantitate slowly cycling malignant cells in solid tumors, using a well-established mouse model of Kras-induced lung cancer (KrasG12D/+). 5-Bromo-2-deoxyuridine (BrdUrd) was administered to tumor-bearing mice, and samples were collected at defined times during pulse and chase phases. Mathematical and statistical modeling of the label-retention data during the chase phase supported the existence of a slowly cycling label-retaining population in this tumor model and permitted the estimation of its proportion and proliferation rate within a tumor. The doubling time of the slowly cycling population was estimated at approximately 5.7 weeks, and this population represented approximately 31% of the total tumor cells in this model system. The mathematical modeling techniques implemented here may be useful in other tumor models where direct observation of cell-cycle kinetics is difficult and may help evaluate tumor cell subpopulations with distinct cell-cycling rates. Cancer Res; 73(12); 3525–33. ©2013 AACR.
Early B-Cell Differentiation in Merkel Cell Carcinomas: Clues to Cellular Ancestry
Authors: zur Hausen Axel , Rennspiess Dorit , Winnepenninckx Veronique , Speel Ernst-Jan , Kurz Anna Kordelia 
Published: April 2013

AbstractMerkel cell carcinoma (MCC) is a highly malignant neuroendocrine nonmelanoma skin cancer, which is associated with the Merkel cell polyoma virus (MCPyV). Recently, expression of the terminal deoxynucleotidyl transferase (TdT) and the paired box gene 5 (PAX 5) has been consistently reported in the majority of MCCs. We tested 21 MCCs for the expression of MCPyV, TdT, PAX5, IgG, IgM, IgA, kappa, and lambda by immunohistochemistry and assessed IgH and Igk rearrangement in all 21 MCCs. All of the MCCs revealed specific expression of PAX5 and 72.8% of the MCCs expressed TdT. In addition, most of the MCCs revealed specific expression of one or more Ig subclasses and kappa or lambda. One MCC did reveal monoclonal IgH and Igk rearrangement next to two other MCCs showing Igk rearrangement. As coexpression of TdT and PAX5 under physiologic circumstances is restricted to pro/pre- and pre-B cells we propose, on the basis of our results, that the cell of origin of MCCs is a pro/pre- or pre-B cell rather than the postmitotic Merkel cells. MCPyV infection and transformation of pro-/pre-B cells are likely to induce the expression of simple cytokeratins as has been shown for SV40 in other nonepithelial cells. This model of cellular ancestry of MCCs might impact therapy and possibly helps to understand why approximately 20% of MCCs are MCPyV-negative. Cancer Res; 73(16); 4982–7. ©2013 AACR.
Blood Levels of Folate at Birth and Risk of Childhood Leukemia
Authors: Chokkalingam Anand P. , Chun Danielle S. , Noonan Emily J. , Pfeiffer Christine M. , Zhang Mindy , Month Stacy R. , Taggart Denah R. , Wiemels Joseph L. , Metayer Catherine , Buffler Patricia A. 
Published: April 2013

AbstractBackground: A role for folate in cancer etiology has long been suspected because of folate's function as a cofactor in DNA methylation and maintenance of DNA synthesis. Previous case–control studies examining the association between risk of childhood acute lymphoblastic leukemia (ALL) and mothers' self-reported folate intake and supplementation have been inconclusive.Materials and Methods: We used a quantitative microbiologic assay to measure newborn folate concentrations in archived dried bloodspots collected at birth from 313 incident ALL cases, 44 incident acute myeloid leukemia (AML) cases, and 405 matched population-based controls.Results: Overall, we found no difference in hemoglobin-normalized newborn folate concentrations (HbFol, nmol/g) between ALL cases and controls (2.76 vs. 2.77, P = 0.97) or between AML cases and controls (2.93 vs. 2.76, P = 0.32). Null results persisted after stratification by both birth period (1982–94, 1995–98, and 1999–2002) to account for the start of folate fortification of grain products in the United States, and by self-reported maternal prepregnancy supplement use. Similarly, no association was observed for major ALL subgroups.Conclusions: Our results do not support an association between birth folate concentrations and risk of childhood AML or major ALL subgroups.Impact: However, they do not rule out a role for folate through exposures after birth or in early stages of fetal development. Cancer Epidemiol Biomarkers Prev; 22(6); 1088–94. ©2013 AACR.