bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relevance of Assembly-Activating Protein for Adeno-associated Virus Vector Production and Capsid Protein Stability in Mammalian and Insect Cells
Authors: Grosse Stefanie , Penaud-Budloo Magalie , Herrmann Anne-Kathrin , Börner Kathleen , Fakhiri Julia , Laketa Vibor , Krämer Chiara , Wiedtke Ellen , Gunkel Manuel , Ménard Lucie , Ayuso Eduard , Grimm Dirk 
Published: August 2017

ABSTRACT
The discovery that adeno-associated virus 2 (AAV2) encodes an eighth protein, called assembly-activating protein (AAP), transformed our understanding of wild-type AAV biology. Concurrently, it raised questions about the role of AAP during production of recombinant vectors based on natural or molecularly engineered AAV capsids. Here, we show that AAP is indeed essential for generation of functional recombinant AAV2 vectors in both mammalian and insect cell-based vector production systems. Surprisingly, we observed that AAV2 capsid proteins VP1 to -3 are unstable in the absence of AAP2, likely due to rapid proteasomal degradation. Inhibition of the proteasome led to an increase of intracellular VP1 to -3 but neither triggered assembly of functional capsids nor promoted nuclear localization of the capsid proteins. Together, this underscores the crucial and unique role of AAP in the AAV life cycle, where it rapidly chaperones capsid assembly, thus preventing degradation of free capsid proteins. An expanded analysis comprising nine alternative AAV serotypes (1, 3 to 9, and rh10) showed that vector production always depends on the presence of AAP, with the exceptions of AAV4 and AAV5, which exhibited AAP-independent, albeit low-level, particle assembly. Interestingly, AAPs from all 10 serotypes could cross-complement AAP-depleted helper plasmids during vector production, despite there being distinct intracellular AAP localization patterns. These were most pronounced for AAP4 and AAP5, congruent with their inability to rescue an AAV2/AAP2 knockout. We conclude that AAP is key for assembly of genuine capsids from at least 10 different AAV serotypes, which has implications for vectors derived from wild-type or synthetic AAV capsids.

IMPORTANCE
Assembly of adeno-associated virus 2 (AAV2) is regulated by the assembly-activating protein (AAP), whose open reading frame overlaps with that of the viral capsid proteins. As the majority of evidence was obtained using virus-like particles composed solely of the major capsid protein VP3, AAP's role in and relevance for assembly of genuine AAV capsids have remained largely unclear. Thus, we established a
trans
-complementation assay permitting assessment of AAP functionality during production of recombinant vectors based on complete AAV capsids and derived from any serotype. We find that AAP is indeed a critical factor not only for AAV2, but also for generation of vectors derived from nine other AAV serotypes. Moreover, we identify a new role of AAP in maintaining capsid protein stability in mammalian and insect cells. Thereby, our study expands our current understanding of AAV/AAP biology, and it concomitantly provides insights into the importance of AAP for AAV vector production.
Inactivated H7 Influenza Virus Vaccines Protect Mice despite Inducing Only Low Levels of Neutralizing Antibodies
Authors: Kamal Ram P. , Blanchfield Kristy , Belser Jessica A. , Music Nedzad , Tzeng Wen-Pin , Holiday Crystal , Burroughs Ashley , Sun Xiangjie , Maines Taronna R. , Levine Min Z. , York Ian A. 
Published: August 2017

ABSTRACT
Avian influenza viruses of the H7 hemagglutinin (HA) subtype present a significant public health threat, as evidenced by the ongoing outbreak of human A(H7N9) infections in China. When evaluated by hemagglutination inhibition (HI) and microneutralization (MN) assays, H7 viruses and vaccines are found to induce lower level of neutralizing antibodies (nAb) than do their seasonal counterparts, making it difficult to develop and evaluate prepandemic vaccines. We have previously shown that purified recombinant H7 HA appear to be poorly immunogenic in that they induce low levels of HI and MN antibodies. In this study, we immunized mice with whole inactivated reverse genetics reassortant (RG) viruses expressing HA and neuraminidase (NA) from 3 different H7 viruses [A/Shanghai/2/2013(H7N9), A/Netherlands/219/2003(H7N7), and A/New York/107/2003(H7N2)] or with human A(H1N1)pdm09 (A/California/07/2009-like) or A(H3N2) (A/Perth16/2009) viruses. Mice produced equivalent titers of antibodies to all viruses as measured by enzyme-linked immunosorbent assay (ELISA). However, the antibody titers induced by H7 viruses were significantly lower when measured by HI and MN assays. Despite inducing very low levels of nAb, H7 vaccines conferred complete protection against homologous virus challenge in mice, and the serum antibodies directed against the HA head region were capable of mediating protection. The apparently low immunogenicity associated with H7 viruses and vaccines may be at least partly related to measuring antibody titers with the traditional HI and MN assays, which may not provide a true measure of protective immunity associated with H7 immunization. This study underscores the need for development of additional correlates of protection for prepandemic vaccines.

IMPORTANCE
H7 avian influenza viruses present a serious risk to human health. Preparedness efforts include development of prepandemic vaccines. For seasonal influenza viruses, protection is correlated with antibody titers measured by hemagglutination inhibition (HI) and virus microneutralization (MN) assays. Since H7 vaccines typically induce low titers in HI and MN assays, they have been considered to be poorly immunogenic. We show that in mice H7 whole inactivated virus vaccines (WIVs) were as immunogenic as seasonal WIVs, as they induced similar levels of overall serum antibodies. However, a larger fraction of the antibodies induced by H7 WIV was nonneutralizing
in vitro
. Nevertheless, the H7 WIV completely protected mice against homologous viral challenge, and antibodies directed against the HA head were the major contributor toward immune protection. Vaccines against H7 avian influenza viruses may be more effective than HI and virus neutralization assays suggest, and such vaccines may need other methods for evaluation.
Crystal Structure of the N-Terminal Half of the Traffic Controller UL37 from Herpes Simplex Virus 1
Authors: Koenigsberg Andrea L. , Heldwein Ekaterina E. 
Published: August 2017

ABSTRACT
Inner tegument protein UL37 is conserved among all three subfamilies of herpesviruses. Studies of UL37 homologs from two alphaherpesviruses, herpes simplex virus 1 (HSV-1) and pseudorabies virus (PRV), have suggested that UL37 plays an essential albeit poorly defined role in intracellular capsid trafficking. At the same time, HSV and PRV homologs cannot be swapped, which suggests that in addition to a conserved function, UL37 homologs also have divergent virus-specific functions. Accurate dissection of UL37 functions requires detailed maps in the form of atomic-resolution structures. Previously, we reported the crystal structure of the N-terminal half of UL37 (UL37N) from PRV. Here, we report the crystal structure of HSV-1 UL37N. Comparison of the two structures reveals that UL37 homologs differ in their overall shapes, distributions of surface charges, and locations of projecting loops. In contrast, the previously identified R2 surface region is structurally conserved. We propose that within the N-terminal half of UL37, functional conservation is centered within the R2 surface region, whereas divergent structural elements pinpoint regions mediating virus-specific functions and may engage different binding partners. Together, the two structures can now serve as templates for a structure-guided exploration of both conserved and virus-specific functions of UL37.

IMPORTANCE
The ability to move efficiently within host cell cytoplasm is essential for replication in all viruses. It is especially important in the neuroinvasive alphaherpesviruses, such as human herpes simplex virus 1 (HSV-1), HSV-2, and veterinarian pseudorabies virus (PRV), that infect the peripheral nervous system and have to travel long distances along axons. Capsid movement in these viruses is controlled by capsid-associated tegument proteins, yet their specific roles have not yet been defined. Systematic exploration of the roles of tegument proteins in capsid trafficking requires detailed navigational charts in the form of their three-dimensional structures. Here, we determined the crystal structure of the N-terminal half of a conserved tegument protein, UL37, from HSV-1. This structure, along with our previously reported structure of the UL37 homolog from PRV, provides a much needed 3-dimensional template for the dissection of both conserved and virus-specific functions of UL37 in intracellular capsid trafficking.
Room for improvement: a randomised controlled trial with nested qualitative interviews on space, place and treatment delivery
Authors: Sandal Louise F , Thorlund Jonas B , Moore Andrew J , Ulrich Roger S , Dieppe Paul A , Roos Ewa M 
Published: August 2017

ObjectiveHealthcare-oriented design in hospitals can promote better clinical outcomes. Creating optimal facilities may increase treatment effects. We investigated the influence of the treatment room on effects of exercise therapy.MethodsIn a mixed-method randomised controlled double-blind trial, middle-aged individuals reporting knee or hip pain performed 8 weeks of exercise therapy in (1) a newly built physically enhanced environment, (2) a standard environment or (3) were waitlisted, receiving no intervention. Participants and therapists were blind to study aim. Primary outcome was participants’ Global Perceived Effect (GPE; seven-point Likert scale). Six nested focus group interviews with participants (n=25) and individual interviews with therapists (n=2) explored experiences of the environments.Results42 people exercised in the physically enhanced environment, 40 in the standard environment, 21 were waitlisted. Contrary to our hypothesis, the treatment response seemed greater in the standard environment for GPE (0.98, 95% CI0.5 to 1.4) than for the physically enhanced environment (0.37, 95% CI −0.2 to 0.9), between-group difference (0.61, 95% CI −0.1 to 1.3) did not reach statistical significance (p=0.07). Waitlist group reported no improvement (−0.05 95% CI −0.5 to 0.4). In interviews, participants from the standard environment expressed greater social cohesion and feeling at home. Qualitative themes identified; reflection, sense of fellowship and transition. Secondary patient-reported outcomes and qualitative findings supported the primary finding, while improvements in muscle strength and aerobic capacity did not differ between exercise groups.ConclusionResults suggest that the physical environment contributes to treatment response. Matching patients’ preferences to treatment rooms may improve patient-reported outcomes.Trial registration numberClinicalTrials.gov identifier:NCT02043613.
Factors influencing the reporting of adverse medical device events: qualitative interviews with physicians about higher risk implantable devices
Authors: Gagliardi Anna R , Ducey Ariel , Lehoux Pascale , Turgeon Thomas , Ross Sue , Trbovich Patricia , Easty Anthony , Bell Chaim , Urbach David 
Published: August 2017

BackgroundPostmarket surveillance of medical devices is reliant on physician reporting of adverse medical device events (AMDEs). Little is known about factors that influence whether and how physicians report AMDEs, an essential step in developing behaviour change interventions. This study explored factors that influence AMDE reporting.MethodsQualitative interviews were conducted with physicians who differed by specialties that implant cardiovascular and orthopaedic devices prone to AMDEs, geography and years in practice. Participants were asked if and how they reported AMDEs, and the influencing factors. Themes were identified inductively using constant comparative technique, and reviewed and discussed by the research team on four occasions.ResultsTwenty-two physicians of varying specialty, region, organisation and career stage perceived AMDE reporting as unnecessary, not possible or futile due to multiple factors. Physicians viewed AMDEs as an expected part of practice that they could manage by switching to different devices or developing work-around strategies for problematic devices. Physician beliefs and behaviour were reinforced by limited healthcare system capacity and industry responsiveness. The healthcare system lacked processes and infrastructure to detect, capture, share and act on information about AMDEs, and constrained device choice through purchasing contracts. The device industry did not respond to reports of AMDEs from physicians or improve their products based on such reports. As a result, participants said they used devices that were less than ideal for a given patient, leading to suboptimal patient outcomes.ConclusionsThere may be little point in solely educating or incentivising individual physicians to report AMDEs unless environmental conditions are conducive to doing so. Future research should explore policies that govern AMDEs and investigate how to design and implement postmarket surveillance systems.
Supporting family carers in home-based end-of-life care: using participatory action research to develop a training programme for support workers and volunteers
Authors: Caswell Glenys , Hardy Beth , Ewing Gail , Kennedy Sheila , Seymour Jane 
Published: August 2017

BackgroundFamily carers are crucial in enabling dying people to stay at home, but are often not prepared for their caring role, receiving little support from formal health and social care services. It is increasingly likely that any help or support family carers receive will be provided by a third sector organisation on either a voluntary basis or by untrained carer support workers.ObjectivesTo produce a training programme designed to equip carer support workers and volunteers with the basic skills and knowledge needed to support family carers.Process of developmentParticipatory action research, a collaborative form of working in which those who are affected by an issue take a lead role in the research, was used. Bereaved carers acting as research partners, support workers and representatives of third sector organisations took an active part in designing, developing, piloting and refining the programme in a number of interlinked stages. During development, the programme was piloted on four occasions and evaluated by 36 trainees and 3 trainers.Final training programmeThe outcome of the project is an innovative, 1-day training programme, offering an introduction to supporting family carers who are looking after someone approaching the end of life. The use of participatory action research methods enabled the development of a programme that addresses support needs identified by bereaved carers and training needs identified by carer support workers.The finished programme includes all the materials necessary to run a training day for support workers and volunteers: facilitator’s notes, trainee workbook, slides, promotional poster and pre-course reading for trainees. Knowledge of issues involved in end-of-life and palliative care is not required, although some experience in delivering training is advisable.ConclusionThe programme evaluated well during development, but further research is required to examine the transfer of learning into the workplace.
Running training experience attenuates disuse atrophy in fast-twitch skeletal muscles of rats
Authors: Nakamura Keisuke , Ohsawa Ikumi , Masuzawa Ryo , Konno Ryotaro , Watanabe Atsuya , Kawano Fuminori 
Published: August 2017

Responsiveness to physiological stimuli, such as exercise and muscular inactivation, differs in individuals. However, the mechanisms responsible for these individual differences remain poorly understood. We tested whether a prior experience of exercise training affects the responses of skeletal muscles to unloading. Young rats were assigned to perform daily running training with a treadmill for 8 wk. After an additional 8 wk of normal habitation, the rats were hindlimb unloaded by tail suspension for 1 wk. Fast-twitch plantaris, gastrocnemius, and tibialis anterior muscles did not atrophy after unloading in rats with training experience, although soleus muscle lost weight similar to sedentary rats. We also analyzed the transcriptome in plantaris muscle with RNA sequencing followed by hierarchical clustering analysis and found that a subset of genes that were generally upregulated in sedentary rats after unloading were less responsive in rats with training experience. The distribution of histone 3 was diminished at the loci of these genes during the training period. Although the deposition of histone 3 was restored after an additional period of normal habitation, the incorporation of H3.3 variant was promoted in rats with training experience. This remodeling of nucleosomes closely correlated to the conformational changes of chromatin and suppressed gene expression in response to unloading. These results suggest that exercise training stimulated the early turnover of histone components, which may alter the responsiveness of gene transcription to physiological stimuli. NEW & NOTEWORTHY The present study demonstrates that disuse atrophy was suppressed in fast-twitch skeletal muscles of rats with training experience in early life. We also found a subset of genes that were less responsive to unloading in the muscle of rats with training experience. It was further determined that exercise training caused an early turnover of nucleosome components, which may alter the responsiveness of genes to stimulus in later life.
A latent low-dimensional common input drives a pool of motor neurons: a probabilistic latent state-space model
Authors: Feeney Daniel F. , Meyer François G. , Noone Nicholas , Enoka Roger M. 
Published: August 2017

Motor neurons appear to be activated with a common input signal that modulates the discharge activity of all neurons in the motor nucleus. It has proven difficult for neurophysiologists to quantify the variability in a common input signal, but characterization of such a signal may improve our understanding of how the activation signal varies across motor tasks. Contemporary methods of quantifying the common input to motor neurons rely on compiling discrete action potentials into continuous time series, assuming the motor pool acts as a linear filter, and requiring signals to be of sufficient duration for frequency analysis. We introduce a space-state model in which the discharge activity of motor neurons is modeled as inhomogeneous Poisson processes and propose a method to quantify an abstract latent trajectory that represents the common input received by motor neurons. The approach also approximates the variation in synaptic noise in the common input signal. The model is validated with four data sets: a simulation of 120 motor units, a pair of integrate-and-fire neurons with a Renshaw cell providing inhibitory feedback, the discharge activity of 10 integrate-and-fire neurons, and the discharge times of concurrently active motor units during an isometric voluntary contraction. The simulations revealed that a latent state-space model is able to quantify the trajectory and variability of the common input signal across all four conditions. When compared with the cumulative spike train method of characterizing common input, the state-space approach was more sensitive to the details of the common input current and was less influenced by the duration of the signal. The state-space approach appears to be capable of detecting rather modest changes in common input signals across conditions.NEW & NOTEWORTHY We propose a state-space model that explicitly delineates a common input signal sent to motor neurons and the physiological noise inherent in synaptic signal transmission. This is the first application of a deterministic state-space model to represent the discharge characteristics of motor units during voluntary contractions.
Latency transition of plasminogen activator inhibitor type 1 is evolutionarily conserved
Authors: Jendroszek Agnieszka , Sønnichsen Malene S. , Muñoz Andrés C. , Leyman Kato , Christensen Anni , Petersen Steen , Wang Tobias , Bendixen Christian , Panitz Frank , Andreasen Peter A. , Jensen Jan K. 
Published: August 2017

SummaryPlasminogen activator inhibitor type 1 (PAI-1) is a central regulator of fibrinolysis and tissue remodelling. PAI-1 belongs to the serpin super-family and unlike other inhibitory serpins undergoes a spontaneous inactivation process under physiological conditions, termed latency transition. During latency transition the solvent exposed reactive centre loop is inserted into the central β–sheet A of the molecule, and is no longer accessible to reaction with the protease. More than three decades of research on mammalian PAI-1 has not been able to clarify the evolutionary advantage and physiological relevance of latency transition. In order to study the origin of PAI-1 latency transition, we produced PAI-1 from Spiny dogfish shark (Squalus acanthias) and African lungfish (Protopterus sp.), which represent central species in the evolution of vertebrates. Although human PAI-1 and the non-mammalian PAI-1 variants share only approximately 50 % sequence identity, our results showed that all tested PAI–1 variants undergo latency transition with a similar rate. Since the functional stability of PAI–1 can be greatly increased by substitution of few amino acid residues, we conclude that the ability to undergo latency transition must have been a specific selection criterion for the evolution of PAI-1. It appears that all PAI-1 molecules must harbour latency transition to fulfil their physiological function, stressing the importance to further pursue a complete understanding of this molecular phenomenon with possible implication to pharmacological intervention. Our results provide the next step in understanding how the complete role of this important protease inhibitor evolved along with the fibrinolytic system.Supplementary Material to this article is available online at www.thrombosis-online.com.
Superoxide Dismutase 2 is dispensable for platelet function
Authors: Fidler Trevor P. , Rowley Jesse W. , Araujo Claudia , Boudreau Luc H. , Marti Alex , Souvenir Rhonda , Dale Kali , Boilard Eric , Weyrich Andrew S. , Abel E. Dale 
Published: August 2017

SummaryIncreased intracellular reactive oxygen species (ROS) promote platelet activation. The sources of platelet-derived ROS are diverse and whether or not mitochondrial derived ROS, modulates platelet function is incompletely understood. Studies of platelets from patients with sickle cell disease, and diabetes suggest a correlation between mitochondrial ROS and platelet dysfunction. Therefore, we generated mice with a platelet specific knockout of superoxide dismutase 2 (SOD2-KO) to determine if increased mitochondrial ROS increases platelet activation. SOD2-KO platelets demonstrated decreased SOD2 activity and increased mitochondrial ROS, however total platelet ROS was unchanged. Mitochondrial function and content were maintained in non-stimulated platelets. However SOD2-KO platelets demonstrated decreased mitochondrial function following thrombin stimulation. In vitro platelet activation and spreading was normal and in vivo, deletion of SOD2 did not change tail-bleeding or arterial thrombosis indices. In pathophysiological models mediated by platelet-dependent immune mechanisms such as sepsis and autoimmune inflammatory arthritis, SOD2-KO mice were phenotypically identical to wildtype controls. These data demonstrate that increased mitochondrial ROS does not result in platelet dysfunction.