The mechanisms by which ANP32 proteins support the influenza polymerase

Influenza A naturally resides asymptomatically in wild aquatic birds. However, cross over into humans can occur and may result in a pandemic if the virus adapts for efficient replication and transmission between immunologically naïve human hosts. Fortunately, pandemics occur infrequently due to the existence of host range barriers. Poor replication of the influenza genome in the human cell nucleus is one of the main barriers that restricts avian origin influenza virus. The most common mutation which can overcome this block is the E627K mutation in the PB2 subunit of the trimeric influenza polymerase complex. Both the absence of a compatible positive factor or the presence of an inhibitory factor in human hosts have been proposed to explain why a polymerase bearing a glutamic acid at position 627 of PB2 is restricted in human cells. Avian ANP32A has been identified as a host factor which can support the activity of an avian origin viral polymerase. However, this polymerase is not compatible with the shorter human orthologues of this protein, human ANP32A and ANP32B. Since these human proteins have been implicated in supporting the activity of a human adapted influenza polymerase, it is hypothesised that the PB2 E627K mutation is an adaptation towards utilising huANP32A and -B. In this study we investigate how the ANP32A proteins are able to support polymerase activity and why species differences in this protein determine its compatibility with polymerases bearing different mutations. This was primarily examined by assessing differences in the interactions between specific ANP32A proteins and viral polymerases. We found that the interactions with trimeric polymerase complex were dependent on the species of ANP32A. These interactions were stabilised at inactive ribonucleoproteins, but dissociated as replication of the viral genome occurred. However, using multiple methods, we concluded that the ability of viral polymerase to co-opt ANP32A was determined by more than differences in interactions alone. As ANP32A can act as an adapter protein in some cases, we also investigated whether the interactome of the polymerase differed in the presence or absence of avian ANP32A. We further explored the impact of two human proteins, SRPK1 and importin alpha7, which differed in their interaction with avian origin polymerase when chicken ANP32A was co-expressed. Finally, we visualised the viral polymerase by overexpression of PA-GFP in human cells and observed differences between an avian origin polymerase and that with humanising mutations. Specifically, the avian origin polymerase appeared to form speckles in the nucleus of human cells. We explored the requirements for formation of these speckles as well as their relationship with ANP32A. This study has allowed us to gain insight into the mechanism by which ANP32A can support influenza virus polymerase. This was explored via several avenues, which led to the identification of other host factors which may affect polymerase activity. Overall, these data have enhanced our understanding of host restriction of influenza virus polymerase and the interplay between host and viral factors.Open Acces

Novel Method of Measuring Electron Positron Colliding Beam Parameters

Through the simultaneous measurement of the transverse size as a function of longitudinal position, and the longitudinal distribution of luminosity, we are able to measure the $\beta_y^\ast$ (vertical envelope function at the collision point), vertical emittance, and bunch length of colliding beams at the Cornell Electron-positron Storage Ring (CESR). This measurement is possible due to the significant ``hourglass'' effect at CESR and the excellent tracking resolution of the CLEO detector.Comment: 11 pages, 4 figures, submitted to NIM

Mechanical deformations of a liquid crystal elastomer at director angles between 0° and 90°: Deducing an empirical model encompassing anisotropic nonlinearity

Despite the wealth of studies reporting mechanical properties of liquid crystal elastomers (LCEs), no theory can currently describe their complete mechanical anisotropy and nonlinearity. Here, we present the first comprehensive study of mechanical anisotropy in an all‐acrylate LCE via tensile tests that simultaneously track liquid crystal (LC) director rotation. We then use an empirical approach to gain a deeper insight into the LCE's mechanical responses at values of strain, up to 1.5, for initial director orientations between 0° and 90°. Using a method analogous to time–temperature superposition, we create master curves for the LCE's mechanical response and use these to deduce a model that accurately predicts the load curve of the LCE for stresses applied at angles between 15° and 70° relative to the initial LC director. This LCE has been shown to exhibit auxetic behavior for deformations perpendicular to the director. Interestingly, our empirical model predicts that the LCE will further demonstrate auxetic behavior when stressed at angles between 54° and 90° to the director. Our approach could be extended to any LCE; so it represents a significant step forward toward models that would aid the further development of LCE theory and the design and modeling of LCE‐based technologies. © 2019 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 1367–137

Toward Programmed Complex Stress-Induced Mechanical Deformations of Liquid Crystal Elastomers

We prepare a liquid crystal elastomer (LCE) with a spatially patterned liquid crystal director field from an all-acrylate LCE. Mechanical deformations of this material lead to a complex and spatially varying deformation with localised body rotations, shears and extensions. Together, these dictate the evolved shape of the deformed film. Using polarising microscopy, we map the local rotation of the liquid crystal director in Eulerian and Lagrangian frames and use these to determine rules for programming complex, stress-induced mechanical shape deformations of LCEs. Moreover, by applying a recently developed empirical model for the mechanical behaviour of our LCE, we predict the non-uniform stress distributions in our material. These results show the promise of empirical approaches to modelling the anisotropic and nonlinear mechanical responses of LCEs which will be important as the community moves toward realising real-world, LCE-based devices

Study of knowledge, attitude, and practices towards current updates of pharmacovigilance and adverse drug reaction reporting among doctors in a tertiary care teaching hospital of Western India

Background: In general, adverse drug reactions (ADRs) are global problems causing both morbidity and mortality. Spontaneous ADR reporting is important to monitor adverse effects of medicines but under reporting is still very prevalent so, there is a need of constant monitoring and rectification of system of Pharmacovigilance. The objective of this study was to evaluate the knowledge, attitude, and practices (KAP) of the healthcare professionals about Pharmacovigilance and to identify the reason for under reporting of ADRs.Methods: A cross-sectional study was carried out using a pretested questionnaire among doctors with minimum qualification MBBS or B.D.S. including faculties, senior and junior residents. Subsequently, analysis of association between education and experience was done by chi square test at P-value <0.05.Results: A pretested questionnaire was distributed among 403 doctors and 240 (59.16%) responded voluntarily. In general, 131 (54.58%) participants noted lack of time to report ADR while 90 (37.50%) participants noted no benefit of reporting already known ADR. On the other hand, total 104 (43.33%) participants were aware about need to report a serious adverse event during “Clinical Trial” within 24 hours to the Ethics Committee. Only 87 (36.25%) participants noted a need of reporting of already known ADR.Conclusions: Participants had good knowledge and attitude towards pharmacovigilance, but the actual practice of ADR reporting is still deficient among them that can be improved by sensitization training and involvement of grass root level health care workers

The role of adenosine in chondrocyte death in murine osteoarthritis and in a murine chondrocyte cell line

SummaryObjectiveTo investigate the role of adenosine in chondrocyte death in murine osteoarthritis (OA).Methods5′-Nucleotidase (5′NT) generates adenosine. Enzyme activity was measured histochemically in normal murine and osteoarthritic STR/ort strain tibial cartilage. Adenosine-mediated cell death was investigated in MC615 chondrocyte cultures. Adenosine receptors (ARs) were assessed by reverse transcriptase polymerase chain reaction (RT-PCR). Cellular uptake of [3H] adenosine was measured with or without the inhibitor, nitrobenzylthioinosine (NBTI). Cell death was assessed by cell counting and DNA laddering following selective receptor stimulation, or after modulating adenosine metabolism with adenosine deaminase (ADA) or adenosine kinase (AK) inhibitors [erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) and Iodotubericidin (Itub)], or with homocysteine (HC). Markers of apoptosis were assessed by Western blotting. Cell studies were validated by incubating normal murine knee joints in a medium containing adenosine and metabolic inhibitors. Apoptotic chondrocytes were identified with the TUNEL reaction.Results5′NT activity in STR/ort tibial cartilage increased with development of OA, especially close to OA lesions. Adenosine induced MC615 cell death in the presence of ADA inhibition (100μM EHNA), or 1mM HC, or both. Adenosine uptake, mediated by NBTI-sensitive adenosine transporters, was required for cell death. ARs were expressed (A2b>A2a>A1) but were not involved in mediating cell death. Cell death involved the activation of caspase-3 and DNA fragmentation and was prevented by inhibiting caspase activity. However, neither caspase-8 nor caspase-9 was detected. Adenosine+EHNA induced chondrocyte apoptosis in normal murine knee joints.ConclusionIncreased adenosine production may induce chondrocyte apoptosis and play a role in OA in STR/ort mice

Understanding the Reasons behind Anticipated Regret for Missing Regular Physical Activity

Anticipated affective reactions to missing physical activity (PA), often labeled anticipated regret, has reliable evidence as a predictor of PA intention and behavior independent of other standard social cognitive constructs. Despite this evidence, the sources of regret are understudied and may come from many different reasons. The purpose of this study was to theme the reasons for why people responded to anticipated regret over missing regular PA for 2 weeks. Participants were a random sample of 120 university students who were primed on the public health definition of PA, completed measures of regret, and were asked to list their reasons for regret. Ninety-five percent of participants expressed that they would regret not being active and gave a total of 357 reasons. The dominant theme (n = 247; 69%) was a missed opportunity to obtain the benefits of PA, followed by shame/guilt for not being able to follow-through with one’s goals or self-categorized role (n = 99; 28%) with a final theme of perceived pressure from others (n = 11; 3%). From a practical perspective, the diversity of these reasons suggest that more clarity on the source of regret should be present in assessment, while building from both attitude and identity theories may help understand how regret motivates PA in future intervention