Hormone Replacement Therapy and Risk of Severe Asthma Exacerbation in Perimenopausal and Postmenopausal Women : 17-Year National Cohort Study

This work was supported by Asthma UK, grant number: AUK-IG-2016-346 and Health Data Research UK. We thank Optimum Patient Care (OPC) and Observational and Pragmatic Research Institute Pte Ltd (OPRI) for making the OPCRD database (www.opcrd.co.uk) available free of charge. B. I. Nwaru acknowledges the support of Knut and Alice Wallenberg Foundation, the Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden, and the VBG Group Herman Krefting Foundation on Asthma and Allergy. A. Sheikh acknowledges support of Health Data Research UK (BREATHE).Peer reviewedPublisher PD

Hormone replacement therapy and asthma onset in menopausal women: National cohort study

© 2020 The Authors Background: There is uncertainty about the role of hormonal replacement therapy (HRT) in the development of asthma. Objective: We investigated whether use of HRT and duration of use was associated with risk of development of asthma in perimenopausal and postmenopausal women. Methods: We constructed a 17-year (from January 1, 2000, to December 31, 2016) open cohort of 353,173 women (aged 46-70 years) from the Optimum Patient Care Database, a longitudinal primary care database from across the United Kingdom. HRT use, subtypes, and duration of use; confounding variables; and asthma onset were defined by using the Read Clinical Classification System. We fitted multilevel Cox regression models to estimate hazard ratios (HRs) with 95% CIs. Results: During the 17-year follow-up (1,340,423 person years), 7,614 new asthma cases occurred, giving an incidence rate of 5.7 (95% CI = 5.5-5.8) per 1,000 person years. Compared with nonuse of HRT, previous use of any (HR = 0.83; 95% CI = 0.76-0.88), estrogen-only (HR = 0.89; 95% CI = 0.84-0.95), or combined estrogen and progestogen (HR = 0.82; 95% CI = 0.76-0.88) HRT was associated with a reduced risk of asthma onset. This was also the case with current use of any (HR = 0.79; 95% CI = 0.74-0.85), estrogen-only (HR = 0.80; 95% CI = 0.73-0.87), and combined estrogen and progestogen (HR = 0.78; 95% CI = 0.70-0.87) HRT. Longer duration of HRT use (1-2 years [HR = 0.93; 95% CI = 0.87-0.99]; 3-4 years [HR = 0.77; 95% CI = 0.70-0.84]; and ≥5 years [HR = 0.71; 95% CI = 0.64-0.78]) was associated with a dose-response reduced risk of asthma onset.Conclusion: We found that HRT was associated with a reduced risk of development of late onset asthma in menopausal women. Further cohort studies are needed to confirm these findings

Optimising monitoring in the management of Crohn's disease: a physician's perspective.

Management of Crohn's disease has traditionally placed high value on subjective symptom assessment; however, it is increasingly appreciated that patient symptoms and objective parameters of inflammation can be disconnected. Therefore, strategies that objectively monitor inflammatory activity should be utilised throughout the disease course to optimise patient management. Initially, a thorough assessment of the severity, location and extent of disease is needed to ensure a correct diagnosis, identify any complications, help assess prognosis and select appropriate therapy. During follow-up, clinical decision-making should be driven by disease activity monitoring, with the aim of optimising treatment for tight disease control. However, few data exist to guide the choice of monitoring tools and the frequency of their use. Furthermore, adaption of monitoring strategies for symptomatic, asymptomatic and post-operative patients has not been well defined. The Annual excHangE on the ADvances in Inflammatory Bowel Disease (IBD Ahead) 2011 educational programme, which included approximately 600 gastroenterologists from 36 countries, has developed practice recommendations for the optimal monitoring of Crohn's disease based on evidence and/or expert opinion. These recommendations address the need to incorporate different modalities of disease assessment (symptom and endoscopic assessment, measurement of biomarkers of inflammatory activity and cross-sectional imaging) into robust monitoring. Furthermore, the importance of measuring and recording parameters in a standardised fashion to enable longitudinal evaluation of disease activity is highlighted.Peer reviewe

BHPR research: qualitative1. Complex reasoning determines patients' perception of outcome following foot surgery in rheumatoid arhtritis

Background: Foot surgery is common in patients with RA but research into surgical outcomes is limited and conceptually flawed as current outcome measures lack face validity: to date no one has asked patients what is important to them. This study aimed to determine which factors are important to patients when evaluating the success of foot surgery in RA Methods: Semi structured interviews of RA patients who had undergone foot surgery were conducted and transcribed verbatim. Thematic analysis of interviews was conducted to explore issues that were important to patients. Results: 11 RA patients (9 ♂, mean age 59, dis dur = 22yrs, mean of 3 yrs post op) with mixed experiences of foot surgery were interviewed. Patients interpreted outcome in respect to a multitude of factors, frequently positive change in one aspect contrasted with negative opinions about another. Overall, four major themes emerged. Function: Functional ability & participation in valued activities were very important to patients. Walking ability was a key concern but patients interpreted levels of activity in light of other aspects of their disease, reflecting on change in functional ability more than overall level. Positive feelings of improved mobility were often moderated by negative self perception ("I mean, I still walk like a waddling duck”). Appearance: Appearance was important to almost all patients but perhaps the most complex theme of all. Physical appearance, foot shape, and footwear were closely interlinked, yet patients saw these as distinct separate concepts. Patients need to legitimize these feelings was clear and they frequently entered into a defensive repertoire ("it's not cosmetic surgery; it's something that's more important than that, you know?”). Clinician opinion: Surgeons' post operative evaluation of the procedure was very influential. The impact of this appraisal continued to affect patients' lasting impression irrespective of how the outcome compared to their initial goals ("when he'd done it ... he said that hasn't worked as good as he'd wanted to ... but the pain has gone”). Pain: Whilst pain was important to almost all patients, it appeared to be less important than the other themes. Pain was predominately raised when it influenced other themes, such as function; many still felt the need to legitimize their foot pain in order for health professionals to take it seriously ("in the end I went to my GP because it had happened a few times and I went to an orthopaedic surgeon who was quite dismissive of it, it was like what are you complaining about”). Conclusions: Patients interpret the outcome of foot surgery using a multitude of interrelated factors, particularly functional ability, appearance and surgeons' appraisal of the procedure. While pain was often noted, this appeared less important than other factors in the overall outcome of the surgery. Future research into foot surgery should incorporate the complexity of how patients determine their outcome Disclosure statement: All authors have declared no conflicts of interes

Regulation of mRNA decapping across atomic and mesoscopic scales

During transcription in the nucleus, messenger RNA (mRNA) is endowed withmodifications that serve as important markers for its regulation in the cell. This includes the addition of a 7-methylguanosine cap (m7G) at the 5’ end, which is important for nuclear export, translation, and degradation of transcripts. Numerous mRNA quality control pathways end in the degradation of transcripts and pathogens can degrade RNA during infection to favor their survival. Removal of the cap structure, or decapping, commits mRNA to degradation and is a highly controlled step in post-transcriptional regulation. The conserved eukaryotic decapping complex Dcp1/Dcp2 is regulated through an intricate network of protein-protein interactions that can inhibit and accelerate decapping. While many of the interfaces required for these interactions have been studied, a mechanistic understanding of their consequences have not been well-characterized. This work describes a mechanism for autoinhibition of decapping and how the protein cofactors Edc3 and Edc1 relieve this autoinhibition to activate decapping through conformational changes in the Dcp2 active site. Furthermore, these regulatory mechanisms contribute to in vitro phase separation that causes localized sites of repressed and accelerated mRNA decapping. Together, these findings demonstrate how regulation at the ångstrom scale is coupled to microscopic behavior to enhance the catalytic power of decapping, which ensures mRNA degradation occurs only when specific conditions are met

Pat1 activates late steps in mRNA decay by multiple mechanisms

Pat1 is a hub for mRNA metabolism, acting in pre-mRNA splicing, translation repression, and mRNA decay. A critical step in all 5'-3' mRNA decay pathways is removal of the 5' cap structure, which precedes and permits digestion of the RNA body by conserved exonucleases. During bulk 5'-3' decay, the Pat1/Lsm1-7 complex engages mRNA at the 3' end and promotes hydrolysis of the cap structure by Dcp1/Dcp2 at the 5' end through an unknown mechanism. We reconstitute Pat1 with 5' and 3' decay factors and show how it activates multiple steps in late mRNA decay. First, we find that Pat1 stabilizes binding of the Lsm1-7 complex to RNA using two conserved short-linear interaction motifs. Second, Pat1 directly activates decapping by binding elements in the disordered C-terminal extension of Dcp2, alleviating autoinhibition and promoting substrate binding. Our results uncover the molecular mechanism of how separate domains of Pat1 coordinate the assembly and activation of a decapping messenger ribonucleoprotein (mRNP) that promotes 5'-3' mRNA degradation

Biomolecular condensates amplify mRNA decapping by biasing enzyme conformation.

Cells organize biochemical processes into biological condensates. P-bodies are cytoplasmic condensates that are enriched in enzymes important for mRNA degradation and have been identified as sites of both storage and decay. How these opposing outcomes can be achieved in condensates remains unresolved. mRNA decapping immediately precedes degradation, and the Dcp1/Dcp2 decapping complex is enriched in P-bodies. Here, we show that Dcp1/Dcp2 activity is modulated in condensates and depends on the interactions promoting phase separation. We find that Dcp1/Dcp2 phase separation stabilizes an inactive conformation in Dcp2 to inhibit decapping. The activator Edc3 causes a conformational change in Dcp2 and rewires the protein-protein interactions to stimulate decapping in condensates. Disruption of the inactive conformation dysregulates decapping in condensates. Our results indicate that the regulation of enzymatic activity in condensates relies on a coupling across length scales ranging from microns to ångstroms. We propose that this regulatory mechanism may control the functional state of P-bodies and related phase-separated compartments

Control of mRNA decapping by autoinhibition.

5' mediated cytoplasmic RNA decay is a conserved cellular process in eukaryotes. While the functions of the structured core domains in this pathway are well-studied, the role of abundant intrinsically disordered regions (IDRs) is lacking. Here we reconstitute the Dcp1:Dcp2 complex containing a portion of the disordered C-terminus and show its activity is autoinhibited by linear interaction motifs. Enhancers of decapping (Edc) 1 and 3 cooperate to activate decapping by different mechanisms: Edc3 alleviates autoinhibition by binding IDRs and destabilizing an inactive form of the enzyme, whereas Edc1 stabilizes the transition state for catalysis. Both activators are required to fully stimulate an autoinhibited Dcp1:Dcp2 as Edc1 alone cannot overcome the decrease in activity attributed to the C-terminal extension. Our data provide a mechanistic framework for combinatorial control of decapping by protein cofactors, a principle that is likely conserved in multiple 5' mRNA decay pathways

Structure of the poxvirus decapping enzyme D9 reveals its mechanism of cap recognition and catalysis

Poxviruses encode decapping enzymes that remove the protective 5' cap from both host and viral mRNAs to commit transcripts for decay by the cellular exonuclease Xrn1. Decapping by these enzymes is critical for poxvirus pathogenicity by means of simultaneously suppressing host protein synthesis and limiting the accumulation of viral double-stranded RNA (dsRNA), a trigger for antiviral responses. Here we present a high-resolution structural view of the vaccinia virus decapping enzyme D9. This Nudix enzyme contains a domain organization different from other decapping enzymes in which a three-helix bundle is inserted into the catalytic Nudix domain. The 5' mRNA cap is positioned in a bipartite active site at the interface of the two domains. Specificity for the methylated guanosine cap is achieved by stacking between conserved aromatic residues in a manner similar to that observed in canonical cap-binding proteins VP39, eIF4E, and CBP20, and distinct from eukaryotic decapping enzyme Dcp2