bluuebunny/crossref_metadata_2025_split huggingface dataset:
Balancing Trained Immunity with Persistent Immune Activation and the Risk of Simian Immunodeficiency Virus Infection in Infant Macaques Vaccinated with Attenuated Mycobacterium tuberculosis or Mycobacterium bovis BCG Vaccine
Authors: Jensen Kara , dela Pena-Ponce Myra Grace , Piatak Michael , Shoemaker Rebecca , Oswald Kelli , Jacobs William R. , Fennelly Glenn , Lucero Carissa , Mollan Katie R. , Hudgens Michael G. , Amedee Angela , Kozlowski Pamela A. , Estes Jacob D. , Lifson Jeffrey D. , Van Rompay Koen K. A. , Larsen Michelle , De Paris Kristina 
Published: September 2016

ABSTRACTOur goal is to develop a pediatric combination vaccine to protect the vulnerable infant population against human immunodeficiency virus type 1 (HIV-1) and tuberculosis (TB) infections. The vaccine consists of an auxotrophMycobacterium tuberculosisstrain that coexpresses HIV antigens. Utilizing an infant rhesus macaque model, we have previously shown that this attenuatedM. tuberculosis(AMtb)-simian immunodeficiency virus (SIV) vaccine is immunogenic, and although the vaccine did not prevent oral SIV infection, a subset of vaccinated animals was able to partially control virus replication. However, unexpectedly, vaccinated infants required fewer SIV exposures to become infected compared to naive controls. Considering that the current TB vaccine,Mycobacterium bovisbacillus Calmette-Guérin (BCG), can induce potent innate immune responses and confer pathogen-unspecific trained immunity, we hypothesized that an imbalance between enhanced myeloid cell function and immune activation might have influenced the outcome of oral SIV challenge in AMtb-SIV-vaccinated infants. To address this question, we used archived samples from unchallenged animals from our previous AMtb-SIV vaccine studies and vaccinated additional infant macaques with BCG or AMtbonly. Our results show that vaccinated infants, regardless of vaccine strain or regimen, had enhanced myeloid cell responses. However, CD4+T cells were concurrently activated, and the persistence of these activated target cells in oral and/or gastrointestinal tissues may have facilitated oral SIV infection. Immune activation was more pronounced in BCG-vaccinated infant macaques than in AMtb-vaccinated infant macaques, indicating a role for vaccine attenuation. These findings underline the importance of understanding the interplay of vaccine-induced immunity and immune activation and its effect on HIV acquisition risk and outcome in infants.
Convallatoxin-Induced Reduction of Methionine Import Effectively Inhibits Human Cytomegalovirus Infection and Replication
Authors: Cohen Tobias , Williams John D. , Opperman Timothy J. , Sanchez Roberto , Lurain Nell S. , Tortorella Domenico 
Published: September 2016

ABSTRACT

Cytomegalovirus (CMV) is a ubiquitous human pathogen that increases the morbidity and mortality of immunocompromised individuals. The current FDA-approved treatments for CMV infection are intended to be virus specific, yet they have significant adverse side effects, including nephrotoxicity and hematological toxicity. Thus, there is a medical need for safer and more effective CMV therapeutics. Using a high-content screen, we identified the cardiac glycoside convallatoxin as an effective compound that inhibits CMV infection. Using a panel of cardiac glycoside variants, we assessed the structural elements critical for anti-CMV activity by both experimental and
in silico
methods. Analysis of the antiviral effects, toxicities, and pharmacodynamics of different variants of cardiac glycosides identified the mechanism of inhibition as reduction of methionine import, leading to decreased immediate-early gene translation without significant toxicity. Also, convallatoxin was found to dramatically reduce the proliferation of clinical CMV strains, implying that its mechanism of action is an effective strategy to block CMV dissemination. Our study has uncovered the mechanism and structural elements of convallatoxin, which are important for effectively inhibiting CMV infection by targeting the expression of immediate-early genes.

IMPORTANCE
Cytomegalovirus is a highly prevalent virus capable of causing severe disease in certain populations. The current FDA-approved therapeutics all target the same stage of the viral life cycle and induce toxicity and viral resistance. We identified convallatoxin, a novel cell-targeting antiviral that inhibits CMV infection by decreasing the synthesis of viral proteins. At doses low enough for cells to tolerate, convallatoxin was able to inhibit primary isolates of CMV, including those resistant to the anti-CMV drug ganciclovir. In addition to identifying convallatoxin as a novel antiviral, limiting mRNA translation has a dramatic impact on CMV infection and proliferation.
Assessment of the PrP
c
Amino-Terminal Domain in Prion Species Barriers
Authors: Davenport Kristen A. , Henderson Davin M. , Mathiason Candace K. , Hoover Edward A. 
Published: September 2016

ABSTRACT

Chronic wasting disease (CWD) in cervids and bovine spongiform encephalopathy (BSE) in cattle are prion diseases that are caused by the same protein-misfolding mechanism, but they appear to pose different risks to humans. We are interested in understanding the differences between the species barriers of CWD and BSE. We used real-time, quaking-induced conversion (RT-QuIC) to model the central molecular event in prion disease, the templated misfolding of the normal prion protein, PrP
c
, to a pathogenic, amyloid isoform, scrapie prion protein, PrP
Sc
. We examined the role of the PrP
c
amino-terminal domain (N-terminal domain [NTD], amino acids [aa] 23 to 90) in cross-species conversion by comparing the conversion efficiency of various prion seeds in either full-length (aa 23 to 231) or truncated (aa 90 to 231) PrP
c
. We demonstrate that the presence of white-tailed deer and bovine NTDs hindered seeded conversion of PrP
c
, but human and bank vole NTDs did the opposite. Additionally, full-length human and bank vole PrP
c
s were more likely to be converted to amyloid by CWD prions than were their truncated forms. A chimera with replacement of the human NTD by the bovine NTD resembled human PrP
c
. The requirement for an NTD, but not for the specific human sequence, suggests that the NTD interacts with other regions of the human PrP
c
to increase promiscuity. These data contribute to the evidence that, in addition to primary sequence, prion species barriers are controlled by interactions of the substrate NTD with the rest of the substrate PrP
c
molecule.

IMPORTANCE
We demonstrate that the amino-terminal domain of the normal prion protein, PrP
c
, hinders seeded conversion of bovine and white-tailed deer PrP
c
s to the prion forms, but it facilitates conversion of the human and bank vole PrP
c
s to the prion forms. Additionally, we demonstrate that the amino-terminal domain of human and bank vole PrP
c
s requires interaction with the rest of the molecule to facilitate conversion by CWD prions. These data suggest that interactions of the amino-terminal domain with the rest of the PrP
c
molecule play an important role in the susceptibility of humans to CWD prions.
The Cytoskeletal Adaptor Obscurin-Like 1 Interacts with the Human Papillomavirus 16 (HPV16) Capsid Protein L2 and Is Required for HPV16 Endocytosis
Authors: Wüstenhagen Elena , Hampe Laura , Boukhallouk Fatima , Schneider Marc A. , Spoden Gilles A. , Negwer Inka , Koynov Kaloian , Kast W. Martin , Florin Luise 
Published: September 2016

ABSTRACT
The human papillomavirus (HPV) capsid protein L2 is essential for viral entry. To gain a deeper understanding of the role of L2, we searched for novel cellular L2-interacting proteins. A yeast two-hybrid analysis uncovered the actin-depolymerizing factor gelsolin, the membrane glycoprotein dysadherin, the centrosomal protein 68 (Cep68), and the cytoskeletal adaptor protein obscurin-like 1 protein (OBSL1) as putative L2 binding molecules. Pseudovirus (PsV) infection assays identified OBSL1 as a host factor required for gene transduction by three oncogenic human papillomavirus types, HPV16, HPV18, and HPV31. In addition, we detected OBSL1 expression in cervical tissue sections and noted the involvement of OBSL1 during gene transduction of primary keratinocytes by HPV16 PsV. Complex formation of HPV16 L2 with OBSL1 was demonstrated in coimmunofluorescence and coimmunoprecipitation studies after overexpression of L2 or after PsV exposure. We observed a strong colocalization of OBSL1 with HPV16 PsV and tetraspanin CD151 at the plasma membrane, suggesting a role for OBSL1 in viral endocytosis. Indeed, viral entry assays exhibited a reduction of viral endocytosis in OBSL1-depleted cells. Our results suggest OBSL1 as a novel L2-interacting protein and endocytosis factor in HPV infection.

IMPORTANCE
Human papillomaviruses infect mucosal and cutaneous epithelia, and the high-risk HPV types account for 5% of cancer cases worldwide. As recently discovered, HPV entry occurs by a clathrin-, caveolin-, and dynamin-independent endocytosis via tetraspanin-enriched microdomains. At present, the cellular proteins involved in the underlying mechanism of this type of endocytosis are under investigation. In this study, the cytoskeletal adaptor OBSL1 was discovered as a previously unrecognized interaction partner of the minor capsid protein L2 and was identified as a proviral host factor required for HPV16 endocytosis into target cells. The findings of this study advance the understanding of a so far less well-characterized endocytic pathway that is used by oncogenic HPV subtypes.
Tetherin Antagonism by HIV-1 Group M Nef Proteins
Authors: Arias Juan F. , Colomer-Lluch Marta , von Bredow Benjamin , Greene Justin M. , MacDonald Julie , O'Connor David H. , Serra-Moreno Ruth , Evans David T. 
Published: September 2016

ABSTRACT

Although Nef is the viral gene product used by most simian immunodeficiency viruses to overcome restriction by tetherin, this activity was acquired by the Vpu protein of HIV-1 group M due to the absence of sequences in human tetherin that confer susceptibility to Nef. Thus, it is widely accepted that HIV-1 group M uses Vpu instead of Nef to counteract tetherin. Challenging this paradigm, we identified Nef alleles of HIV-1 group M isolates with significant activity against human tetherin. These Nef proteins promoted virus release and tetherin downmodulation from the cell surface and, in the context of
vpu
-deleted HIV-1 recombinants, enhanced virus replication and resistance to antibody-dependent cell-mediated cytotoxicity (ADCC). Further analysis revealed that the Vpu proteins from several of these viruses lack antitetherin activity, suggesting that under certain circumstances, HIV-1 group M Nef may acquire the ability to counteract tetherin to compensate for the loss of this function by Vpu. These observations illustrate the remarkable plasticity of HIV-1 in overcoming restriction by tetherin and challenge the prevailing view that all HIV-1 group M isolates use Vpu to counteract tetherin.

IMPORTANCE
Most viruses of HIV-1 group M, the main group of HIV-1 responsible for the global AIDS pandemic, use their Vpu proteins to overcome restriction by tetherin (BST-2 or CD317), which is a transmembrane protein that inhibits virus release from infected cells. Here we show that the Nef proteins of certain HIV-1 group M isolates can acquire the ability to counteract tetherin. These results challenge the current paradigm that HIV-1 group M exclusively uses Vpu to counteract tetherin and underscore the importance of tetherin antagonism for efficient viral replication.
Multiple Strategies Reveal a Bidentate Interaction between the Nipah Virus Attachment and Fusion Glycoproteins
Authors: Stone Jacquelyn A. , Vemulapati Bhadra M. , Bradel-Tretheway Birgit , Aguilar Hector C. 
Published: September 2016

ABSTRACT
The paramyxoviral family contains many medically important viruses, including measles virus, mumps virus, parainfluenza viruses, respiratory syncytial virus, human metapneumovirus, and the deadly zoonotic henipaviruses Hendra and Nipah virus (NiV). To both enter host cells and spread from cell to cell within infected hosts, the vast majority of paramyxoviruses utilize two viral envelope glycoproteins: the attachment glycoprotein (G, H, or hemagglutinin-neuraminidase [HN]) and the fusion glycoprotein (F). Binding of G/H/HN to a host cell receptor triggers structural changes in G/H/HN that in turn trigger F to undergo a series of conformational changes that result in virus-cell (viral entry) or cell-cell (syncytium formation) membrane fusion. The actual regions of G/H/HN and F that interact during the membrane fusion process remain relatively unknown though it is generally thought that the paramyxoviral G/H/HN stalk region interacts with the F head region. Studies to determine such interactive regions have relied heavily on coimmunoprecipitation approaches, whose limitations include the use of detergents and the micelle-mediated association of proteins. Here, we developed a flow-cytometric strategy capable of detecting membrane protein-protein interactions by interchangeably using the full-length form of G and a soluble form of F, or vice versa. Using both coimmunoprecipitation and flow-cytometric strategies, we found a bidentate interaction between NiV G and F, where both the stalk and head regions of NiV G interact with F. This is a new structural-biological finding for the paramyxoviruses. Additionally, our studies disclosed regions of the NiV G and F glycoproteins dispensable for the G and F interactions.

IMPORTANCE
Nipah virus (NiV) is a zoonotic paramyxovirus that causes high mortality rates in humans, with no approved treatment or vaccine available for human use. Viral entry into host cells relies on two viral envelope glycoproteins: the attachment (G) and fusion (F) glycoproteins. Binding of G to the ephrinB2 or ephrinB3 cell receptors triggers conformational changes in G that in turn cause F to undergo conformational changes that result in virus-host cell membrane fusion and viral entry. It is currently unknown, however, which specific regions of G and F interact during membrane fusion. Past efforts to determine the interacting regions have relied mainly on coimmunoprecipitation, a technique with some pitfalls. We developed a flow-cytometric assay to study membrane protein-protein interactions, and using this assay we report a bidentate interaction whereby both the head and stalk regions of NiV G interact with NiV F, a new finding for the paramyxovirus family.
Extragenic Suppression of a Mutation in Herpes Simplex Virus 1 UL34 That Affects Lamina Disruption and Nuclear Egress
Authors: Vu Amber , Poyzer Chelsea , Roller Richard 
Published: September 2016

ABSTRACT
Nuclear egress of herpesviruses is accompanied by changes in the architecture of the nuclear membrane and nuclear lamina that are thought to facilitate capsid access to the inner nuclear membrane (INM) and curvature of patches of the INM around the capsid during budding. Here we report the properties of a point mutant of pUL34 (Q163A) that fails to induce gross changes in nuclear architecture or redistribution of lamin A/C. The UL34(Q163A) mutant shows a roughly 100-fold defect in single-step growth, and it forms small plaques. This mutant has a defect in nuclear egress, and furthermore, it fails to disrupt nuclear shape or cause observable displacement of lamin A/C despite retaining the ability to recruit the pUS3 and PKC protein kinases and to mediate phosphorylation of emerin. Extragenic suppressors of the UL34(Q163A) phenotype were isolated, and all of them carry a single mutation of arginine 229 to leucine in UL31. Surprisingly, although this UL31 mutation largely restores virus replication, it does not correct the lamina disruption defect, suggesting that, in Vero cells, changes in nuclear shape and gross displacements of lamin A/C may facilitate but are unnecessary for nuclear egress.

IMPORTANCE
Herpesvirus nuclear egress is an essential and conserved process that requires close association of the viral capsid with the inner nuclear membrane and budding of the capsid into that membrane. Access to the nuclear membrane and tight curvature of that membrane are thought to require disruption of the nuclear lamina that underlies the inner nuclear membrane, and consistent with this idea, herpesvirus infection induces biochemical and architectural changes at the nuclear membrane. The significance of the nuclear membrane architectural changes is poorly characterized. The results presented here address that deficiency in our understanding and show that a combination of mutations in two of the viral nuclear egress factors results in a failure to accomplish at least two components of lamina disruption while still allowing relatively efficient viral replication, suggesting that changes in nuclear shape and displacement of lamins are not necessary for herpes simplex virus 1 (HSV-1) nuclear egress.
The Glycosylphosphatidylinositol-Anchored Variable Region of Llama Heavy Chain-Only Antibody JM4 Efficiently Blocks both Cell-Free and T Cell-T Cell Transmission of Human Immunodeficiency Virus Type 1
Authors: Liu Lihong , Wang Weiming , Matz Julie , Ye Chaobaihui , Bracq Lucie , Delon Jerome , Kimata Jason T. , Chen Zhiwei , Benichou Serge , Zhou Paul 
Published: September 2016

ABSTRACT

The variable regions (VHHs) of two heavy chain-only antibodies, JM2 and JM4, from llamas that have been immunized with a trimeric gp140 bound to a CD4 mimic have been recently isolated (here referred to as VHH JM2 and VHH JM4, respectively). JM2 binds the CD4-binding site of gp120 and neutralizes HIV-1 strains from subtypes B, C, and G. JM4 binds gp120 and neutralizes HIV-1 strains from subtypes A, B, C, A/E, and G in a CD4-dependent manner. In the present study, we constructed glycosylphosphatidylinositol (GPI)-anchored VHH JM2 and JM4 along with an E4 control and transduced them into human CD4
+
cell lines and primary CD4 T cells. We report that by genetically linking the VHHs with a GPI attachment signal, VHHs are targeted to the lipid rafts of the plasma membranes. Expression of GPI-VHH JM4, but not GPI-VHH E4 and JM2, on the surface of transduced TZM.bl cells potently neutralizes multiple subtypes of HIV-1 isolates, including tier 2 or 3 strains, transmitted founders, quasispecies, and soluble single domain antibody (sdAb) JM4-resistant viruses. Moreover, transduction of CEMss-CCR5 cells with GPI-VHH JM4, but not with GPI-VHH E4, confers resistance to both cell-free and T cell-T cell transmission of HIV-1 and HIV-1 envelope-mediated fusion. Finally, GPI-VHH JM4-transduced human primary CD4 T cells efficiently resist both cell-free and T cell-T cell transmission of HIV-1. Thus, we conclude that VHH JM4, when targeted to the lipid rafts of the plasma membrane, efficiently neutralizes HIV-1 infection via both cell-free and T cell-T cell transmission. Our findings should have important implications for GPI-anchored antibody-based therapy against HIV-1.

IMPORTANCE
Lipid rafts are specialized dynamic microdomains of the plasma membrane and have been shown to be gateways for HIV-1 budding as well as entry into T cells and macrophages. In nature, many glycosylphosphatidylinositol (GPI)-anchored proteins localize in the lipid rafts. In the present study, we developed GPI-anchored variable regions (VHHs) of two heavy chain-only antibodies, JM2 and JM4, from immunized llamas. We show that by genetically linking the VHHs with a GPI attachment signal, VHHs are targeted to the lipid rafts of the plasma membranes. GPI-VHH JM4, but not GPI-VHH JM2, in transduced CD4
+
cell lines and human primary CD4 T cells not only efficiently blocks diverse HIV-1 strains, including tier 2 or 3 strains, transmitted founders, quasispecies, and soluble sdAb JM4-resistant strains, but also efficiently interferes T cell-T cell transmissions of HIV-1 and HIV-1 envelope-mediated fusion. Our findings should have important implications in GPI-anchored antibody-based therapy against HIV-1.
Obesity in adolescents with chronic fatigue syndrome: an observational study
Authors: Norris T , Hawton K , Hamilton-Shield J , Crawley E 
Published: September 2016

ObjectiveIdentify the prevalence of obesity in patients with chronic fatigue syndrome (CFS) compared with healthy adolescents, and those identified with CFS in a population cohort.DesignCross-sectional analysis of multiple imputed data.SettingData from UK paediatric CFS/myalgic encephalomyelitis (CFS/ME) services compared with data collected at two time points in the Avon Longitudinal Study of Parents and Children (ALSPAC).Patients1685 adolescents who attended a CFS/ME specialist service between 2004 and 2014 and 13 978 adolescents aged approximately 13 years and 16 years participating in the ALSPAC study.Main outcome measuresBody mass index (BMI) (kg/m2), sex-specific and age-specific BMI Z-scores (relative to the International Obesity Task Force cut-offs) and prevalence of obesity (%).ResultsAdolescents who had attended specialist CFS/ME services had a higher prevalence of obesity (age 13 years: 9.28%; age 16 years: 16.43%) compared with both adolescents classified as CFS/ME in ALSPAC (age 13 years: 3.72%; age 16 years: 5.46%) and those non-CFS in ALSPAC (age 13 years: 4.18%; age 16 years: 4.46%). The increased odds of obesity in those who attended specialist services (relative to non-CFS in ALSPAC) was apparent at both 13 years (OR: 2.31 (1.54 to 3.48)) and 16 years, with a greater likelihood observed at 16 years (OR: 4.07 (2.04 to 8.11)).ConclusionsWe observed an increased prevalence of obesity in adolescents who were affected severely enough to be referred to a specialist CFS/ME service. Further longitudinal research is required in order to identify the temporal relationship between the two conditions.
Can a mobile app improve the quality of patient care provided by trainee doctors? Analysis of trainees’ case reports
Authors: Webb Katie , Bullock Alison , Dimond Rebecca , Stacey Mark 
Published: September 2016

ObjectivesTo explore how a medical textbook app (‘iDoc’) supports newly qualified doctors in providing high-quality patient care.DesignThe iDoc project, funded by the Wales Deanery, provides new doctors with an app which gives access to key medical textbooks. Participants’ submitted case reports describing self-reported accounts of specific instances of app use. The size of the data set enabled analysis of a subsample of ‘complex’ case reports. Of the 568 case reports submitted by Foundation Year 1s (F1s)/Year 2s (F2s), 142 (25%) detailed instances of diagnostic decision-making and were identified as ‘complex’. We analysed these data against the Quality Improvement (QI) Framework using thematic content analysis.SettingClinical settings across Wales, UK.ParticipantsNewly qualified doctors (2012–2014; n=114), F1 and F2.InterventionsThe iDoc app, powered by Dr Companion software, provided newly qualified doctors in Wales with a selection of key medical textbooks via individuals’ personal smartphone.ResultsDoctors’ use of the iDoc app supported 5 of the 6 QI elements: efficiency, timeliness, effectiveness, safety and patient-centredness. None of the case reports were coded to the equity element. Efficiency was the element which attracted the highest number of case report references. We propose that the QI Framework should be expanding to include ‘learning’ as a 7th element.ConclusionsAccess to key medical textbooks via an app provides trusted and valuable support to newly qualified doctors during a period of transition. On the basis of these doctors’ self-reported accounts, our evidence indicates that the use of the app enhances efficiency, effectiveness and timeliness of patient-care in addition consolidating a safe, patient-centred approach. We propose that there is scope to extend the QI Framework by incorporating ‘learning’ as a 7th element in recognition of the relationship between providing high-quality care through educational engagement.