Mechanistic insights into the activation of the IKK kinase complex by the Kaposi’s Sarcoma Herpes virus oncoprotein vFLIP

Constitutive activation of the canonical NF-κB signaling pathway is a major factor in Kaposi’s Sarcoma Herpes virus (KSHV) pathogenesis where it is essential for the survival of primary effusion lymphoma (PEL). Central to this process is persistent upregulation of the inhibitor of κB kinase (IKK) kinase complex by the virally encoded oncoprotein vFLIP. Although the physical interaction between vFLIP and the IKK kinase regulatory component essential for persistent activation, IKKγ, has been well characterized, it remains unclear how the kinase subunits are rendered active mechanistically. Using a combination of cell-based assays, biophysical techniques, and structural biology, we demonstrate here that vFLIP alone is sufficient to activate the IKK kinase complex. Furthermore, we identify weakly stabilised, high molecular weight vFLIP-IKKγ assemblies that are key to the activation process. Taken together, our results are the first to reveal that vFLIP induced NF-κB activation pivots on the formation of structurally specific vFLIP-IKKγ multimers which have an important role in rendering the kinase subunits active through a process of autophosphorylation. This mechanism of NF-κB activation is in contrast to those utilised by endogenous cytokines and cellular FLIP homologues

Association between Sexual Activity and Human Papillomavirus (HPV) Vaccine Initiation and Completion among College Students

HPV vaccination is most effective if received before initiation of sexual activity. Previous studies suggested that young adult women who were not sexually active were not interested in receiving the vaccine because they did not think it was necessary. Whether this misperception is still prevalent today-and also shared by men-is unknown. This study examined whether sexual activity was associated with HPV vaccine uptake (initiation and completion) among university students. A cross-sectional study was conducted between February and May 2021 among students (n = 951) at a public Midwestern University. Sexual activity was categorized as never or ever had oral and/or vaginal sex. Outcome variables were HPV vaccine initiation, defined as receipt of ≥1 dose, and completion, defined as receipt of ≥3 doses. Multivariable logistic regression models estimated the association between sexual activity and HPV vaccine uptake, adjusting for sociodemographic factors. Approximately 18% of students reported never engaging in sexual activity. Overall, 45.5% initiated the HPV vaccine, and 16.5% completed the vaccine series. After adjusting for covariates, compared to students that reported never engaging in sexual activity, those that had ever engaged in sexual activity were more likely to have initiated the vaccine series (aOR = 2.06, 95% CI: 1.34-3.17); however, no difference was observed for completion. HPV vaccination was low; sexually naïve students were less likely to initiate the HPV vaccine. Since sexually naïve students may benefit from receiving the HPV vaccination, targeted interventions should be implemented towards this population to help increase vaccination rates and prevent HPV-associated diseases

Using Village Health Teams for Effective Ultrasound Education in Rural Uganda

Maternal and child health conditions, many of which can be detected by ultrasound, represent the highest burden of disease in Uganda. Imaging the World (ITW) is a not-for-profit organization which integrates high quality, affordable ultrasound services into rural health facilities. Of all the challenges faced with implementation of ITW programs in Uganda, lack of sensitization to ultrasound represented the greatest barrier. The Village Health Team (VHT) is an existing public health “train the trainer” model sponsored by the Uganda Ministry of Health which provides public health training to community volunteers. Trained VHT members were recruited to help with ultrasound community outreach and education. These VHT members were successful in achieving dramatic community acceptance and increased utilization of ultrasound services in rural communities. This has led to significant contributions in improving population health in low-resource settings

Probing the Solution Structure of IκB Kinase (IKK) Subunit γ and Its Interaction with Kaposi Sarcoma-associated Herpes Virus Flice-interacting Protein and IKK Subunit β by EPR Spectroscopy.

Viral flice-interacting protein (vFLIP), encoded by the oncogenic Kaposi sarcoma-associated herpes virus (KSHV), constitutively activates the canonical nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) pathway. This is achieved through subversion of the IκB kinase (IKK) complex (or signalosome), which involves a physical interaction between vFLIP and the modulatory subunit IKKγ. Although this interaction has been examined both in vivo and in vitro, the mechanism by which vFLIP activates the kinase remains to be determined. Because IKKγ functions as a scaffold, recruiting both vFLIP and the IKKα/β subunits, it has been proposed that binding of vFLIP could trigger a structural rearrangement in IKKγ conducive to activation. To investigate this hypothesis we engineered a series of mutants along the length of the IKKγ molecule that could be individually modified with nitroxide spin labels. Subsequent distance measurements using electron paramagnetic resonance spectroscopy combined with molecular modeling and molecular dynamics simulations revealed that IKKγ is a parallel coiled-coil whose response to binding of vFLIP or IKKβ is localized twisting/stiffening and not large-scale rearrangements. The coiled-coil comprises N- and C-terminal regions with distinct registers accommodated by a twist: this structural motif is exploited by vFLIP, allowing it to bind and subsequently activate the NF-κB pathway. In vivo assays confirm that NF-κB activation by vFLIP only requires the N-terminal region up to the transition between the registers, which is located directly C-terminal of the vFLIP binding site

Claudin-10 is required for relay of left–right patterning cues from Hensen’s node to the lateral plate mesoderm

AbstractSpecies-specific symmetry-breaking events at the left–right organizer (LRO) drive an evolutionarily-conserved cascade of gene expression in the lateral plate mesoderm that is required for the asymmetric positioning of organs within the body cavity. The mechanisms underlying the transfer of the left and right laterality information from the LRO to the lateral plate mesoderm are poorly understood. Here, we investigate the role of Claudin-10, a tight junction protein, in facilitating the transfer of left–right identity from the LRO to the lateral plate mesoderm. Claudin-10 is asymmetrically expressed on the right side of the chick LRO, Hensen’s node. Gain- and loss-of-function studies demonstrated that right-sided expression of Claudin-10 is essential for normal rightward heart tube looping, the first morphological asymmetry during organogenesis. Manipulation of Claudin-10 expression did not perturb asymmetric gene expression at Hensen’s node, but did disrupt asymmetric gene expression in the lateral plate mesoderm. Bilateral expression of Claudin-10 at Hensen’s node prevented expression of Nodal, Lefty-2 and Pitx2c in the left lateral plate mesoderm, while morpholino knockdown of Claudin-10 inhibited expression of Snail1 in the right lateral plate mesoderm. We also determined that amino acids that are predicted to affect ion selectivity and protein interactions that bridge Claudin-10 to the actin cytoskeleton were essential for its left–right patterning function. Collectively, our data demonstrate a novel role for Claudin-10 during the transmission of laterality information from Hensen’s node to both the left and right sides of the embryo and demonstrate that tight junctions have a critical role during the relay of left–right patterning cues from Hensen’s node to the lateral plate mesoderm

Interpretative Phenomenological Analysis of Soldiers’ Experiences of Being Married and Serving in the British Army

© 2016, Copyright © Taylor & Francis Group, LLC. ABSTRACT: Research suggests certain aspects of military life, especially operational deployments, may negatively impact military marriages. However, much of this research is from the United States and uses deductive quantitative methods. Qualitative research investigating the lived experiences of forming and maintaining marriages was conducted with six male U.K. Army personnel. Semistructured interviews were analyzed, using Interpretative Phenomenological Analysis, identifying five themes, each representing different dilemmas the soldiers’ had to balance to maintain successful marriages and Army careers. These five themes are best understood as practical, emotional, and cultural dilemmas that can be alleviated with practical and emotional methods; such factors could be used to build resilience in soldier’s marriages. These possible resilience factors could shape the content of interventions to increase resiliency in military marriages

Prompt atmospheric neutrino fluxes: perturbative QCD models and nuclear effects

We evaluate the prompt atmospheric neutrino flux at high energies using three different frameworks for calculating the heavy quark production cross section in QCD: NLO perturbative QCD, $k_T$ factorization including low-$x$ resummation, and the dipole model including parton saturation. We use QCD parameters, the value for the charm quark mass and the range for the factorization and renormalization scales that provide the best description of the total charm cross section measured at fixed target experiments, at RHIC and at LHC. Using these parameters we calculate differential cross sections for charm and bottom production and compare with the latest data on forward charm meson production from LHCb at $7$ TeV and at $13$ TeV, finding good agreement with the data. In addition, we investigate the role of nuclear shadowing by including nuclear parton distribution functions (PDF) for the target air nucleus using two different nuclear PDF schemes. Depending on the scheme used, we find the reduction of the flux due to nuclear effects varies from $10\%$ to $50 \%$ at the highest energies. Finally, we compare our results with the IceCube limit on the prompt neutrino flux, which is already providing valuable information about some of the QCD models.Comment: 61 pages, 25 figures, 11 table