bluuebunny/crossref_metadata_2025_split huggingface dataset:
Induction of Broadly Reactive Anti-Hemagglutinin Stalk Antibodies by an H5N1 Vaccine in Humans
Authors: Nachbagauer Raffael , Wohlbold Teddy John , Hirsh Ariana , Hai Rong , Sjursen Haakon , Palese Peter , Cox Rebecca J. , Krammer Florian 
Published: September 2014

ABSTRACT
Influenza virus infections are a major public health concern and cause significant morbidity and mortality worldwide. Current vaccines are effective but strain specific due to their focus on the immunodominant globular head domain of the hemagglutinin (HA). It has been hypothesized that sequential exposure of humans to hemagglutinins with divergent globular head domains but conserved stalk domains could refocus the immune response to broadly neutralizing epitopes in the stalk. Humans have preexisting immunity against H1 (group 1 hemagglutinin), and vaccination with H5 HA (also group 1)—which has a divergent globular head domain but a similar stalk domain—represents one such sequential-exposure scenario. To test this hypothesis, we used novel reagents based on chimeric hemagglutinins to screen sera from an H5N1 clinical trial for induction of stalk-specific antibodies by quantitative enzyme-linked immunosorbent assay (ELISA) and neutralization assays. Importantly, we also investigated the biological activity of these antibodies in a passive transfer in a mouse challenge model. We found that the H5N1 vaccine induced high titers of stalk-reactive antibodies which were biologically active and protective in the passive-transfer experiment. The induced response showed exceptional breadth toward divergent group 1 hemagglutinins but did not extend to group 2 hemagglutinins. These data provide evidence for the hypothesis that sequential exposure to hemagglutinins with divergent globular head domains but conserved stalk domains can refocus the immune response toward the conserved stalk domain. Furthermore, the results support the concept of a chimeric hemagglutinin universal influenza virus vaccine strategy that is based on the same principle.

IMPORTANCE
Influenza virus vaccines have to be reformulated and readministered on an annual basis. The development of a universal influenza virus vaccine could abolish the need for this cumbersome and costly process and would also enhance our pandemic preparedness. This study addressed the following questions, which are essential for the development of a hemagglutinin stalk-based universal influenza virus vaccine. (i) Can stalk-reactive antibodies be boosted by vaccination with divergent HAs that share conserved epitopes? (ii) How long-lived are these vaccine-induced stalk-reactive antibody responses? (iii) What is the breadth of this reactivity? (iv) Are these antibodies functional and protective? Our results further strengthen the concept of induction of stalk-reactive antibodies by sequential exposure to hemagglutinin immunogens with conserved stalk and divergent head domains. A universal influenza virus vaccine based on the same principles seems possible and might have a significant impact on global human health.
Cholesterol-Dependent Membrane Fusion Induced by the gp41 Membrane-Proximal External Region–Transmembrane Domain Connection Suggests a Mechanism for Broad HIV-1 Neutralization
Authors: Apellániz Beatriz , Rujas Edurne , Carravilla Pablo , Requejo-Isidro José , Huarte Nerea , Domene Carmen , Nieva José L. 
Published: September 2014

ABSTRACT
The HIV-1 glycoprotein 41 promotes fusion of the viral membrane with that of the target cell. Structural, biochemical, and biophysical studies suggest that its membrane-proximal external region (MPER) may interact with the HIV-1 membrane and induce its disruption and/or deformation during the process. However, the high cholesterol content of the envelope (ca. 40 to 50 mol%) imparts high rigidity, thereby acting against lipid bilayer restructuring. Here, based on the outcome of vesicle stability assays, all-atom molecular dynamics simulations, and atomic force microscopy observations, we propose that the conserved sequence connecting the MPER with the N-terminal residues of the transmembrane domain (TMD) is involved in HIV-1 fusion. This junction would function by inducing phospholipid protrusion and acyl-chain splay in the cholesterol-enriched rigid envelope. Supporting the functional relevance of such a mechanism, membrane fusion was inhibited by the broadly neutralizing 4E10 antibody but not by a nonneutralizing variant with the CDR-H3 loop deleted. We conclude that the MPER-TMD junction embodies an envelope-disrupting C-terminal fusion peptide that can be targeted by broadly neutralizing antibodies.

IMPORTANCE
Fusion of the cholesterol-enriched viral envelope with the cell membrane marks the beginning of the infectious HIV-1 replicative cycle. Consequently, the Env glycoprotein-mediated fusion function constitutes an important clinical target for inhibitors and preventive vaccines. Antibodies 4E10 and 10E8 bind to one Env vulnerability site located at the gp41 membrane-proximal external region (MPER)–transmembrane domain (TMD) junction and block infection. These antibodies display broad viral neutralization, which underscores the conservation and functionality of the MPER-TMD region. In this work, we combined biochemical assays with molecular dynamics simulations and microscopy observations to characterize the unprecedented fusogenic activity of the MPER-TMD junction. The fact that such activity is dependent on cholesterol and inhibited by the broadly neutralizing 4E10 antibody emphasizes its physiological relevance. Discovery of this functional element adds to our understanding of the mechanisms underlying HIV-1 infection and its blocking by antibodies.
Early Preservation of CXCR5
+
PD-1
+
Helper T Cells and B Cell Activation Predict the Breadth of Neutralizing Antibody Responses in Chronic HIV-1 Infection
Authors: Cohen Kristen , Altfeld Marcus , Alter Galit , Stamatatos Leonidas 
Published: September 2014

ABSTRACT

Much is known about the characteristics of broadly neutralizing antibodies (bNAbs) generated during HIV-1 infection, but little is known about immunological mechanisms responsible for their development in only a minority of those infected by HIV-1. By monitoring longitudinally a cohort of HIV-1-infected subjects, we observed that the preservation of CXCR5
+
CD4
+
T helper cell frequencies and activation status of B cells during the first year of infection correlates with the maximum breadth of plasma neutralizing antibody responses during chronic infection independently of viral load. Although, during the first year of infection, no differences were observed in the abilities of peripheral CXCR5
+
CD4
+
T helper cells to induce antibody secretion by autologous naive B cells, higher frequencies of class-switched antibodies were detected in cocultures of CXCR5
+
CD4
+
T and B cells from the subjects who later developed broadly neutralizing antibody responses than those who did not. Furthermore, B cells from the former subjects had higher expression of
AICDA
than B cells from the latter subjects, and transcript levels correlated with the frequency of CXCR5
+
CD4
+
T cells. Thus, the early preservation of CXCR5
+
CD4
+
T cells and B cell function are central to the development of bNAbs. Our study provides a possible explanation for their infrequent generation during HIV-1 infection.

IMPORTANCE
Broadly neutralizing antibodies are developed by HIV-1-infected subjects, but so far (and despite intensive efforts over the past 3 decades) they have not been elicited by immunization. Understanding how bNAbs are generated during natural HIV-1 infection and why only some HIV-1-infected subjects generate such antibodies will assist our efforts to elicit bNAbs by immunization. CXCR5
+
PD-1
+
CD4
+
T cells are critical for the development of high-affinity antigen-specific antibody responses. In our study, we found that the HIV-1-infected subjects who develop bNAbs have a higher frequency of peripheral CXCR5
+
PD-1
+
CD4
+
T cells in early infection and also that this frequency mirrored what was observed in uninfected subjects and correlated with the level of B cell activation across subjects. Our study highlights the critical role helper T cell function has in the elicitation of broadly neutralizing antibody responses in the context of HIV infection.
Herpes Simplex Virus Internalization into Epithelial Cells Requires Na
+
/H
+
Exchangers and p21-Activated Kinases but neither Clathrin- nor Caveolin-Mediated Endocytosis
Authors: Devadas Deepika , Koithan Thalea , Diestel Randi , Prank Ute , Sodeik Beate , Döhner Katinka 
Published: September 2014

ABSTRACT

Herpes simplex virus 1 (HSV-1) is an alphaherpesvirus that has been reported to infect some epithelial cell types by fusion at the plasma membrane but others by endocytosis. To determine the molecular mechanisms of productive HSV-1 cell entry, we perturbed key endocytosis host factors using specific inhibitors, RNA interference (RNAi), or overexpression of dominant negative proteins and investigated their effects on HSV-1 infection in the permissive epithelial cell lines Vero, HeLa, HEp-2, and PtK
2
. HSV-1 internalization required neither endosomal acidification nor clathrin- or caveolin-mediated endocytosis. In contrast, HSV-1 gene expression and internalization were significantly reduced after treatment with 5-(
N
-ethyl-
N
-isopropyl)amiloride (EIPA). EIPA blocks the activity of Na
+
/H
+
exchangers, which are plasma membrane proteins implicated in all forms of macropinocytosis. HSV-1 internalization furthermore required the function of p21-activated kinases that contribute to macropinosome formation. However, in contrast to some forms of macropinocytosis, HSV-1 did not enlist the activities of protein kinase C (PKC), tyrosine kinases, C-terminal binding protein 1, or dynamin to activate its internalization. These data suggest that HSV-1 depends on Na
+
/H
+
exchangers and p21-activated kinases either for macropinocytosis or for local actin rearrangements required for fusion at the plasma membrane or subsequent passage through the actin cortex underneath the plasma membrane.

IMPORTANCE
After initial replication in epithelial cells, herpes simplex viruses (HSVs) establish latent infections in neurons innervating these regions. Upon primary infection and reactivation from latency, HSVs cause many human skin and neurological diseases, particularly in immunocompromised hosts, despite the availability of effective antiviral drugs. Many viruses use macropinocytosis for virus internalization, and many host factors mediating this entry route have been identified, although the specific perturbation profiles vary for different host and viral cargo. In addition to an established entry pathway via acidic endosomes, we show here that HSV-1 internalization depended on sodium-proton exchangers at the plasma membrane and p21-activated kinases. These results suggest that HSV-1 requires a reorganization of the cortical actin cytoskeleton, either for productive cell entry via pH-independent fusion from macropinosomes or for fusion at the plasma membrane, and subsequent cytosolic passage to microtubules that mediate capsid transport to the nucleus for genome uncoating and replication.
Transcutaneous electrical nerve stimulation as adjunct to primary care management for tennis elbow: pragmatic randomised controlled trial (TATE trial)
Authors: Chesterton Linda S , Lewis A Martyn , Sim Julius , Mallen Christian D , Mason Elizabeth E , Hay Elaine M , van der Windt Daniëlle A 
Published: September 2014

STUDY QUESTIONCan transcutaneous electrical nerve stimulation (TENS), as a patient controlled adjunct to primary care management for tennis elbow, provide superior pain relief to primary care management alone.SUMMARY ANSWERTENS conferred no additional clinical benefit over primary care management consisting of information and advice on analgesia and exercise for patients with tennis elbow, probably partly owing to poor adherence to treatment recommendations.WHAT IS KNOWN AND WHAT THIS PAPER ADDSA need exists for safe, self administered interventions to provide pain relief for patients with tennis elbow. TENS as an adjunct to primary care management failed to show any additional pain relief compared with primary care management alone.
Barriers and facilitators to implementation of the Liverpool Care Pathway in the Netherlands: a qualitative study
Authors: Raijmakers Natasja , Dekkers Anneke , Galesloot Cilia , van Zuylen Lia , van der Heide Agnes 
Published: September 2014

ObjectivesThe Liverpool Care Pathway (LCP) is a quality instrument for the dying patient. This study evaluates barriers and facilitators to its implementation in the Netherlands from the perspective of key stakeholders, to inform future implementation processes.MethodsAn interview study was conducted among 28 stakeholders involved in implementation of the LCP in the Netherlands, followed by a consecutive focus group with 8 interviewees to discuss and validate the findings of the interview study. Interviews were conducted by telephone and the notes taken during the interviews and focus group were transcribed into non-verbatim transcripts. Data collected during the interviews and focus group were evaluated using thematic analysis.ResultsAccording to the stakeholders, a context analysis prior to implementation was useful to find the appropriate orientation to adequately motivate healthcare professionals as well as management. The main contributing factors were the quality of the LCP (including its evidence-based character and completeness), and that it fitted the needs of healthcare professionals. During the implementation phase, a multidisciplinary project team, competent support and continuous monitoring were identified as important facilitators. Furthermore, for successful implementation, a facilitator working in liaison with others was helpful. To guarantee sustainability of the use of the LCP, it was important to disentangle tasks from the project leader and formally integrate these into the quality systems of the organisation.ConclusionsThe Dutch experience with large-scale implementation of the LCP has identified important barriers and facilitators to the implementation of a quality instrument within palliative care. To successfully implement such a promising instrument, liaison with others is important. The sense of being part of a process of improvement is valuable, while consolidation of this idea contributes to successful implementation.
Qualification of a Noninvasive Magnetic Resonance Imaging Biomarker to Assess Tumor Oxygenation
Authors: Colliez Florence , Neveu Marie-Aline , Magat Julie , Cao Pham Thanh Trang , Gallez Bernard , Jordan Bénédicte F. 
Published: September 2014

Abstract
Purpose: Although hypoxia has been long recognized as a crucial factor impairing tumor response in many therapeutic schemes, atraumatic and reliable methods of individually quantifying tumor oxygenation are still lacking in day-to-day clinical practice. The aim of this work was to investigate the potentially quantitative properties of our recently described noninvasive magnetic resonance (MR) technique “MOBILE” (mapping of oxygen by imaging lipids relaxation enhancement) and to qualify this endogenous contrast as a tumor hypoxia marker.
Experimental Design: The “MOBILE” technique, which assesses the longitudinal MR relaxation rate, R1, of lipid protons, was benchmarked with the parent technique which assesses the global (or water) R1, in response to a hyperoxic challenge (carbogen breathing) and to a hypoxic challenge (combretastatin A4) in MDA-MB-231 xenografts and in NT2 mammary tumors. Electron paramagnetic resonance (EPR) oximetry was used to quantitatively assess the tumor pO2 in matching tumors longitudinally.
Results and Conclusion: Our study evidenced that (i) positive and negative changes in tumor oxygenation can be detected using MOBILE; (ii) a change in the R1 of lipids is positively correlated with a change in the tumor pO2 (P = 0.0217, r = 0.5097); (iii) measured lipid R1 values are positively correlated with absolute pO2 values in both tumor models (P = 0.0275, r = 0.3726); and (iv) changes in the R1 of lipids are more sensitive than changes in the global R1. As this technique presents unique translational properties, it seems promising for the individual longitudinal monitoring of tumor oxygenation in a clinical setting. Clin Cancer Res; 20(21); 5403–11. ©2014 AACR.
Inhibition of NANOG/NANOGP8 Downregulates MCL-1 in Colorectal Cancer Cells and Enhances the Therapeutic Efficacy of BH3 Mimetics
Authors: Mattoo Abid R. , Zhang Jingyu , Espinoza Luis A. , Jessup J. Milburn 
Published: September 2014

Abstract
Purpose: High levels of BCL-2 family members in colorectal carcinoma cause resistance to treatment. Inhibition of NANOG or its paralog NANOGP8 reduces the proliferation, stemness, and tumorigenicity of colorectal carcinoma cells. Our hypothesis was that inhibition of NANOG/NANOGP8 enhances the cytotoxic effect of BH3 mimetics targeting BCL-2 family members in colorectal carcinoma cells through reducing expression of MCL-1, a prosurvival BCL-2 protein.
Experimental Design: Lentiviral vector (LV) shRNA to NANOG (shNG-1) or NANOGP8 (shNp8-1) transduced colorectal carcinoma cells that were also exposed to the BH3 mimetics ABT-737 or ABT-199 in vivo in colorectal carcinoma xenografts and in vitro where proliferation, protein and gene expression, and apoptosis were measured.
Results: Clone A and CX-1 were sensitive to ABT-737 and ABT-199 at IC50s of 2 to 9 μmol/L but LS174T was resistant with IC50s of 18 to 30 μmol/L. Resistance was associated with high MCL-1 expression in LS174T. LVshNG-1 or LVshNp8-1 decreased MCL-1 expression, increased apoptosis, and decreased replating efficiency in colorectal carcinoma cells treated with either ABT-737 or ABT-199 compared with the effects of either BH3 mimetic alone. Inhibition or overexpression of MCL-1 alone replicated the effects of LVshNG-1 or LVshNp8-1 in increasing or decreasing the apoptosis caused with the BH3 mimetic. The combination therapy inhibited the growth of LS174T xenografts in vivo compared with untreated controls or treatment with only LV shRNA or ABT-737.
Conclusions: Inhibition of NANOGP8 or NANOG enhances the cytotoxicity of BH3 mimetics that target BCL-2 family members. Gene therapy targeting the NANOGs may increase the efficacy of BH3 mimetics in colorectal carcinoma. Clin Cancer Res; 20(21); 5446–55. ©2014 AACR.
Effect of aspirin intake at bedtime versus on awakening on circadian rhythm of platelet reactivity
Authors: Saris Anno , van Oostrom Monique , Snoep Jaapjan , Rosendaal Frits , Zwaginga Jaap , Eikenboom Jeroen , van der Meer Pieter , van der Bom Johanna , Bonten Tobias 
Published: September 2014

SummaryThe risk of acute cardiovascular events is highest during morning hours, and platelet activity peaks during morning hours. The effect of timing of aspirin intake on circadian rhythm and morning peak of platelet reactivity is not known. It was our objective to evaluate the effect of timing of aspirin intake on circadian rhythm and morning peak of platelet reactivity. A randomised open-label cross-over trial in healthy subjects (n=14) was conducted. Participants used acetylsalicylic acid (80 mg) on awakening or at bedtime for two periods of two weeks, separated by a four-week wash-out period. At the end of both periods blood was drawn every 3 hours to measure COX-1-dependent (VerifyNow- Aspirin; Serum Thromboxane B2 [STxB2]) and COX-1-independent (flow cytometry surface CD62p expression; microaggregation) platelet activity. VerifyNow platelet reactivity over the whole day was similar with intake on awakening and at bedtime (mean difference: –9 [95 % confidence interval (CI) –21 to 4]). However, the morning increase in COX-1-dependent platelet activity was reduced by intake of aspirin at bedtime compared with on awakening (mean difference VerifyNow: –23 Aspirin Reaction Units [CI –50 to 4]; STxB2: –1.7 ng/ml [CI –2.7 to –0.8]). COX-1-independent assays were not affected by aspirin intake or its timing. Low-dose aspirin taken at bedtime compared with intake on awakening reduces COX-1-dependent platelet reactivity during morning hours in healthy subjects. Future clinical trials are required to investigate whether simply switching to aspirin intake at bedtime reduces the risk of cardiovascular events during the high risk morning hours.
Two Further Blood Pressure Loci Identified in Ion Channel Genes With a Genecentric Approach
Authors: McCarthy Nina S. , Vangjeli Ciara , Cavalleri Gianpiero L. , Delanty Norman , Shianna Kevin V. , Surendran Praveen , O’Brien Eoin , Munroe Patricia B. , Masca Nicholas , Tomaszewski Maciej , Samani Nilesh J. , Stanton Alice V. 
Published: September 2014

Background—
Blood pressure (BP) is highly heritable, but our understanding of the genetic causes underlying variations in BP is incomplete. In this study, we explored whether novel loci associated with BP could be identified using a genecentric approach in 3 community-based cohorts with accurate BP measurements.

Methods and Results—

Genotyping of 1857 single nucleotide polymorphisms (SNPs) in 91 ion channel genes was performed in a discovery cohort (n=358). Thirty-four SNPs associated with BP traits (
P
≤0.01) were followed up in an independent population (n=387); significant SNPs from this analysis were looked up in another independent population (n=1010) and meta-analyzed. Repeated clinic and ambulatory measurements were available for all but the discovery cohort (clinic only). Association analyses were performed, with systolic, diastolic, and pulse pressures as quantitative traits, adjusting for age and sex. Quantile–quantile plots indicated that the genecentric approach resulted in an inflation of association signals. Of the 29 SNPs taken forward from the discovery cohort, 2 SNPs were associated with BP phenotypes with the same direction of effect, with experiment-wide significance, in follow-up cohort I. These were rs2228291, in the chloride channel gene
CLCN2
, and rs10513488, in the potassium channel gene
KCNAB1
. Both associations were subsequently replicated in follow-up cohort II.

Conclusions—
Using a genecentric design and 3 well-phenotyped populations, this study identified 2 previously unreported, biologically plausible, genetic associations with BP. These results suggest that dense genotyping of genes, in pathways known to influence BP, could add to candidate-gene and Genome Wide Association studies in further explaining BP heritability.