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The Unfolded Protein Response Modulates a Phosphoinositide-Binding Protein through the IRE1-bZIP60 Pathway

Phosphoinositides function as lipid signals in plant development and stress tolerance by binding with partner proteins. We previously reported that Arabidopsis (Arabidopsis thaliana) phosphoinositide-specific phospholipase C2 functions in the endoplasmic reticulum (ER) stress response. However, the underlying molecular mechanisms of how phosphoinositides act in the ER stress response remain elusive. Here, we report that a phosphoinositide-binding protein, SMALLER TRICHOMES WITH VARIABLE BRANCHES (SVB), is involved in the ER stress tolerance. SVB contains a DUF538 domain with unknown function; orthologs are exclusively found in Viridiplantae. We established that SVB is ubiquitously expressed in plant tissues and is localized to the ER, Golgi apparatus, prevacuolar compartment, and plasma membrane. The knockout mutants of svb showed enhanced tolerance to ER stress, which was genetically complemented by transducing genomic SVB. SVB showed time-dependent induction after tunicamycin-induced ER stress, which depended on IRE1 and bZIP60 but not bZIP17 and bZIP28 in the unfolded protein response (UPR). A protein–lipid overlay assay showed specific binding of SVB to phosphatidylinositol 3,5-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate. SVB is therefore suggested to be the plant-specific phosphoinositide-binding protein whose expression is controlled by the UPR through the IRE1-bZIP60 pathway in Arabidopsis.




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Arabidopsis DNA Replication Initiates in Intergenic, AT-Rich Open Chromatin

The selection and firing of DNA replication origins play key roles in ensuring that eukaryotes accurately replicate their genomes. This process is not well documented in plants due in large measure to difficulties in working with plant systems. We developed a new functional assay to label and map very early replicating loci that must, by definition, include at least a subset of replication origins. Arabidopsis (Arabidopsis thaliana) cells were briefly labeled with 5-ethynyl-2'-deoxy-uridine, and nuclei were subjected to two-parameter flow sorting. We identified more than 5500 loci as initiation regions (IRs), the first regions to replicate in very early S phase. These were classified as strong or weak IRs based on the strength of their replication signals. Strong initiation regions were evenly spaced along chromosomal arms and depleted in centromeres, while weak initiation regions were enriched in centromeric regions. IRs are AT-rich sequences flanked by more GC-rich regions and located predominantly in intergenic regions. Nuclease sensitivity assays indicated that IRs are associated with accessible chromatin. Based on these observations, initiation of plant DNA replication shows some similarity to, but is also distinct from, initiation in other well-studied eukaryotic systems.




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Phosphomimetic T335D Mutation of Hydroxypyruvate Reductase 1 Modifies Cofactor Specificity and Impacts Arabidopsis Growth in Air

Photorespiration is an essential process in oxygenic photosynthetic organisms triggered by the oxygenase activity of Rubisco. In peroxisomes, photorespiratory HYDROXYPYRUVATE REDUCTASE1 (HPR1) catalyzes the conversion of hydroxypyruvate to glycerate together with the oxidation of a pyridine nucleotide cofactor. HPR1 regulation remains poorly understood; however, HPR1 phosphorylation at T335 has been reported. By comparing the kinetic properties of phosphomimetic (T335D), nonphosphorylatable (T335A), and wild-type recombinant Arabidopsis (Arabidopsis thaliana) HPR1, it was found that HPR1-T335D exhibits reduced NADH-dependent hydroxypyruvate reductase activity while showing improved NADPH-dependent activity. Complementation of the Arabidopsis hpr1-1 mutant by either wild-type HPR1 or HPR1-T335A fully complemented the photorespiratory growth phenotype of hpr1-1 in ambient air, whereas HPR1-T335D-containing hpr1-1 plants remained smaller and had lower photosynthetic CO2 assimilation rates. Metabolite analyses indicated that these phenotypes were associated with subtle perturbations in the photorespiratory cycle of HPR1-T335D-complemented hpr1-1 rosettes compared to all other HPR1-containing lines. Therefore, T335 phosphorylation may play a role in the regulation of HPR1 activity in planta, although it was not required for growth under ambient air controlled conditions. Furthermore, improved NADP-dependent HPR1 activities in peroxisomes could not compensate for the reduced NADH-dependent HPR1 activity.




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Responses of a Newly Evolved Auxotroph of Chlamydomonas to B12 Deprivation

The corrinoid B12 is synthesized only by prokaryotes yet is widely required by eukaryotes as an enzyme cofactor. Microalgae have evolved B12 dependence on multiple occasions, and we previously demonstrated that experimental evolution of the non–B12-requiring alga Chlamydomonas reinhardtii in media supplemented with B12 generated a B12-dependent mutant (hereafter metE7). This clone provides a unique opportunity to study the physiology of a nascent B12 auxotroph. Our analyses demonstrate that B12 deprivation of metE7 disrupts C1 metabolism, causes an accumulation of starch and triacylglycerides, and leads to a decrease in photosynthetic pigments, proteins, and free amino acids. B12 deprivation also caused a substantial increase in reactive oxygen species, which preceded rapid cell death. Survival could be improved without compromising growth by simultaneously depriving the cells of nitrogen, suggesting a type of cross protection. Significantly, we found further improvements in survival under B12 limitation and an increase in B12 use efficiency after metE7 underwent a further period of experimental evolution, this time in coculture with a B12-producing bacterium. Therefore, although an early B12-dependent alga would likely be poorly adapted to coping with B12 deprivation, association with B12-producers can ensure long-term survival whilst also providing a suitable environment for evolving mechanisms to tolerate B12 limitation better.




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The Occurrence of Sulfated Salicinoids in Poplar and Their Formation by Sulfotransferase1

Salicinoids form a specific class of phenolic glycosides characteristic of the Salicaceae. Although salicinoids accumulate in large amounts and have been shown to be involved in plant defense, their biosynthesis is unclear. We identified two sulfated salicinoids, salicin-7-sulfate and salirepin-7-sulfate, in black cottonwood (Populus trichocarpa). Both compounds accumulated in high amounts in above-ground tissues including leaves, petioles, and stems, but were also found at lower concentrations in roots. A survey of salicin-7-sulfate and salirepin-7-sulfate in a subset of poplar (Populus sp.) and willow (Salix sp.) species revealed a broader distribution within the Salicaceae. To elucidate the formation of these compounds, we studied the sulfotransferase (SOT) gene family in P. trichocarpa (PtSOT). One of the identified genes, PtSOT1, was shown to encode an enzyme able to convert salicin and salirepin into salicin-7-sulfate and salirepin-7-sulfate, respectively. The expression of PtSOT1 in different organs of P. trichocarpa matched the accumulation of sulfated salicinoids in planta. Moreover, RNA interference-mediated knockdown of SOT1 in gray poplar (Populus x canescens) resulted in decreased levels of sulfated salicinoids in comparison to wild-type plants, indicating that SOT1 is responsible for their formation in planta. The presence of a nonfunctional SOT1 allele in black poplar (Populus nigra) was shown to correlate with the absence of salicin-7-sulfate and salirepin-7-sulfate in this species. Food choice experiments with leaves from wild-type and SOT1 knockdown trees suggest that sulfated salicinoids do not affect the feeding preference of the generalist caterpillar Lymantria dispar. A potential role of the sulfated salicinoids in sulfur storage and homeostasis is discussed.




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Dehydroascorbate Reductases and Glutathione Set a Threshold for High-Light-Induced Ascorbate Accumulation

Plants require a high concentration of ascorbate as a redox buffer for survival under stress conditions, such as high light. Dehydroascorbate reductases (DHARs) are enzymes that catalyze the reduction of DHA to ascorbate using reduced glutathione (GSH) as an electron donor, allowing rapid ascorbate recycling. However, a recent study using an Arabidopsis (Arabidopsis thaliana) triple mutant lacking all three DHAR genes (herein called dhar) did not find evidence for their role in ascorbate recycling under oxidative stress. To further study the function of DHARs, we generated dhar Arabidopsis plants as well as a quadruple mutant line combining dhar with an additional vtc2 mutation that causes ascorbate deficiency. Measurements of ascorbate in these mutants under low- or high-light conditions indicated that DHARs have a nonnegligible impact on full ascorbate accumulation under high light, but that they are dispensable when ascorbate concentrations are low to moderate. Because GSH itself can reduce DHA nonenzymatically, we used the pad2 mutant that contains ~30% of the wild-type GSH level. The pad2 mutant accumulated ascorbate at a wild-type level under high light; however, when the pad2 mutation was combined with dhar, there was near-complete inhibition of high-light–dependent ascorbate accumulation. The lack of ascorbate accumulation was consistent with a marked increase in the ascorbate degradation product threonate. These findings indicate that ascorbate recycling capacity is limited in dhar pad2 plants, and that both DHAR activity and GSH content set a threshold for high-light–induced ascorbate accumulation.




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Transcription Factors BLH2 and BLH4 Regulate Demethylesterification of Homogalacturonan in Seed Mucilage

The polysaccharide pectin is a major component of the plant cell wall. The pectic glycan homogalacturonan (HG) is a proportionally small but important component of a specialized seed cell wall called mucilage. HG is synthesized in a highly methylesterified form, and, following secretion, is de-methylesterified by pectin methylesterases (PMEs). The degree of methylesterification of HG determines the structural and functional properties of pectin, but how methylesterification is regulated remains largely unknown. Here, we identified two BEL1-Like homeodomain (BLH) transcription factors, BLH2 and BLH4, as positive regulators of HG de-methylesterification in Arabidopsis (Arabidopsis thaliana) seed coat mucilage. BLH2 and BLH4 were significantly expressed in mucilage secretory cells during seed mucilage production. BLH2 and BLH4 single mutants exhibited no obvious mucilage phenotype, but the blh2 blh4 double mutant displayed significantly reduced mucilage adherence to the seed. Reduced mucilage adherence in blh2 blh4 was caused by decreased PME activity in the seed coat, which increased the degree of methylesterification of HG in mucilage. The expression of several PME metabolism-related genes, including PME58, PECTIN METHYLESTERASE INHIBITOR6, SEEDSTICK, and MYB52 was significantly altered in blh2 blh4 seeds. BLH2 and BLH4 directly activated PME58 expression by binding to its TGACAGGT cis-element. Moreover, pme58 mutants exhibited reduced mucilage adherence similar to that of blh2 blh4, and the blh2 blh4 pme58 triple mutant exhibited no additional mucilage adherence defects. Furthermore, overexpression of PME58 in blh2 blh4 rescued the mucilage adherence defect. Together, these results demonstrate that BLH2 and BLH4 redundantly regulate de-methylesterification of HG in seed mucilage by directly activating PME58.




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Specific Lhc Proteins Are Bound to PSI or PSII Supercomplexes in the Diatom Thalassiosira pseudonana

Despite the ecological relevance of diatoms, many aspects of their photosynthetic machinery remain poorly understood. Diatoms differ from the green lineage of oxygenic organisms by their photosynthetic pigments and light-harvesting complex (Lhc) proteins, the latter of which are also called fucoxanthin-chlorophyll proteins (FCP). These are composed of three groups of proteins: Lhcf as the main group, Lhcr that are PSI associated, and Lhcx that are involved in photoprotection. The FCP complexes are assembled in trimers and higher oligomers. Several studies have investigated the biochemical properties of purified FCP complexes, but limited knowledge is available about their interaction with the photosystem cores. In this study, isolation of stable supercomplexes from the centric diatom Thalassiosira pseudonana was achieved. To preserve in vivo structure, the separation of thylakoid complexes was performed by native PAGE and sucrose density centrifugation. Different subpopulations of PSI and PSII supercomplexes were isolated and their subunits identified. Analysis of Lhc antenna composition identified Lhc(s) specific for either PSI (Lhcr 1, 3, 4, 7, 10–14, and Lhcf10) or PSII (Lhcf 1–7, 11, and Lhcr2). Lhcx6_1 was reproducibly found in PSII supercomplexes, whereas its association with PSI was unclear. No evidence was found for the interaction between photosystems and higher oligomeric FCPs, comprising Lhcf8 as the main component. Although the subunit composition of the PSII supercomplexes in comparison with that of the trimeric FCP complexes indicated a close mutual association, the higher oligomeric pool is only weakly associated with the photosystems, albeit its abundance in the thylakoid membrane.




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Sensory-Directed Genetic and Biochemical Characterization of Volatile Terpene Production in Kiwifruit

Terpene volatiles are found in many important fruit crops, but their relationship to flavor is poorly understood. Here, we demonstrate using sensory descriptive and discriminant analysis that 1,8-cineole contributes a key floral/eucalyptus note to the aroma of ripe 'Hort16A’ kiwifruit (Actinidia chinensis). Two quantitative trait loci (QTLs) for 1,8-cineole production were identified on linkage groups 27 and 29a in a segregating A. chinensis population, with the QTL on LG29a colocating with a complex cluster of putative terpene synthase (TPS)-encoding genes. Transient expression in Nicotiana benthamiana and analysis of recombinant proteins expressed in Escherichia coli showed four genes in the cluster (AcTPS1a–AcTPS1d) encoded functional TPS enzymes, which produced predominantly sabinene, 1,8-cineole, geraniol, and springene, respectively. The terpene profile produced by AcTPS1b closely resembled the terpenes detected in red-fleshed A. chinensis. AcTPS1b expression correlated with 1,8-cineole content in developing/ripening fruit and also showed a positive correlation with 1,8-cineole content in the mapping population, indicating the basis for segregation is an expression QTL. Transient overexpression of AcTPS1b in Actinidia eriantha fruit confirmed this gene produced 1,8-cineole in Actinidia. Structure-function analysis showed AcTPS1a and AcTPS1b are natural variants at key TPS catalytic site residues previously shown to change enzyme specificity in vitro. Together, our results indicate that AcTPS1b is a key gene for production of the signature flavor terpene 1,8-cineole in ripe kiwifruit. Using a sensory-directed strategy for compound identification provides a rational approach for applying marker-aided selection to improving flavor in kiwifruit as well as other fruits.




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SUMOylation Stabilizes the Transcription Factor DREB2A to Improve Plant Thermotolerance

Heat stress (HS) has serious effects on plant development, resulting in heavy agricultural losses. A critical transcription factor network is involved in plant adaptation to high temperature. DEHYDRATION RESPONSIVE ELEMENT-BINDING PROTEIN2A (DREB2A) is a key transcription factor that functions in plant thermotolerance. The DREB2A protein is unstable under normal temperature and is degraded by the 26S proteasome; however, the mechanism by which DREB2A protein stability dramatically increases in response to HS remains poorly understood. In this study, we found that the DREB2A protein of Arabidopsis (Arabidopsis thaliana) is stabilized under high temperature by the posttranslational modification SUMOylation. Biochemical data indicated that DREB2A is SUMOylated at K163, a conserved residue adjacent to the negative regulatory domain during HS. SUMOylation of DREB2A suppresses its interaction with BPM2, a ubiquitin ligase component, consequently increasing DREB2A protein stability under high temperature. In addition, analysis of plant heat tolerance and marker gene expression indicated that DREB2A SUMOylation is essential for its function in the HS response. Collectively, our data reveal a role for SUMOylation in the maintenance of DREB2A stability under high temperature, thus improving our understanding of the regulatory mechanisms underlying HS response in plant cells.




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MtSSPdb: A New Database for the Small Secreted Peptide Research Community




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Improving Crop Water-Use Efficiency Requires Optimizing the Circadian Clock




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NIT Proteins Regulate Rice Root Plasticity in Response to Nitrate and Ammonium




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CBL2-CIPK6-TST2-Mediated Regulation of Sugar Homeostasis




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AT the Onset of DNA Replication in Arabidopsis




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Phosphoregulation within the Photorespiratory Cycle: Regulate Smarter, Adapt Better?




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What Are the Roles for Dehydroascorbate Reductases and Glutathione in Sustaining Ascorbate Accumulation?




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Hot on the Trail of DREB2A Protein Stability




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Gibberellin Signaling in Plants: Entry of a new MicroRNA Player




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EPSIN1 Contributes to Plant Immunity by Modulating the Abundance of Pattern Recognition Receptors at the Plasma Membrane




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"Detection of SV40 like viral DNA and viral antigens in malignant pleural mesothelioma." M. Ramael, J. Nagels, H. Heylen, S. De Schepper, J. Paulussen, M. De Maeyer and C. Van Haesendonck. Eur Respir J 1999; 14: 1381-1386.




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Severe Pulmonary Hypertension Management Across Europe (PHAROS): an ERS Clinical Research Collaboration

The past 20 years have seen major advances in the understanding and treatment of pulmonary arterial hypertension (PAH; group 1 of the pulmonary hypertension (PH) clinical classification) [1]. A strong basis of knowledge has been acquired in: 1) large randomised clinical trials for drug development; 2) national registries for epidemiology and outcome; and 3) smaller studies on the pathophysiological mechanisms of the disease. This knowledge has been reviewed at World Symposia on Pulmonary Hypertension (the most recent in 2018 [2]) and summarised in European Respiratory Society (ERS)/European Society of Cardiology (ESC) clinical guidelines (the most recent in 2015 [3, 4]). We are, however, much less knowledgeable on specific aspects such as 1) the implementation of guidelines and access to therapies in different European countries; 2) the management of PH crises and progressive (acute on chronic) heart failure; and 3) other groups of PH, such as PH due to lung diseases. Therapeutic strategies also need to be optimised, in particular regarding the combination of drugs, the use of anticoagulants, the place for new medications targeting different pathophysiological pathways, etc.




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Inhaled corticosteroids and COVID-19: a systematic review and clinical perspective

The current coronavirus 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection, raises important questions as to whether pre-morbid use or continued administration of inhaled corticosteroids (ICS) affects the outcomes of acute respiratory infections due to coronavirus. Many physicians are concerned about whether individuals positive for SARS-CoV-2 and taking ICS should continue them or stop them, given that ICS are often regarded as immunosuppressive. A number of key questions arise. Are people with asthma or COPD at increased risk of developing COVID-19? Do ICS modify this risk, either increasing or decreasing it? Do ICS influence the clinical course of COVID-19? (figure 1). Whether ICS modify the risk of developing COVID-19 or the clinical course of COVID-19 in people who do not have lung disease should also be considered (figure 1).




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Looking back to go forward: adherence to inhaled therapy before biologic therapy in severe asthma

For decades inhaled corticosteroids have been central to the management of asthma and are proven to be effective in maintaining symptom control, reducing exacerbations and preserving quality of life through mediation of airway inflammation. However, a small minority of patients have disease which is refractory to high dose inhaled corticosteroid (ICS) therapy and require additional oral corticosteroids to achieve acceptable control of symptoms and exacerbations. Severe asthma represents less than 10% of the total asthma population [1] but is the most serious, life-affecting and costly form of the condition [2].




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A clinically significant bronchodilator response in children: how should it be measured?

We thank F. Guezguez and H. Ben Saad for raising important questions on recommendations for assessing a bronchodilator response (BDR) in children. The authors summarise how recommended outcome measures and cut-offs for BDR in children vary between guidelines, and raise questions about our study [1].




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Predictors of mortality for patients with COVID-19 pneumonia caused by SARS-CoV-2: a prospective cohort study

The aim of this study was to identify factors associated with the death of patients with COVID-19 pneumonia caused by the novel coronavirus SARS-CoV-2.

All clinical and laboratory parameters were collected prospectively from a cohort of patients with COVID-19 pneumonia who were hospitalised to Wuhan Pulmonary Hospital (Wuhan City, Hubei Province, China) between 25 December 2019 and 7 February 2020. Univariate and multivariate logistic regression was performed to investigate the relationship between each variable and the risk of death of COVID-19 pneumonia patients.

In total, 179 patients with COVID-19 pneumonia (97 male and 82 female) were included in the present prospective study, of whom 21 died. Univariate and multivariate logistic regression analysis revealed that age ≥65 years (OR 3.765, 95% CI 1.146-17.394; p=0.023), pre-existing concurrent cardiovascular or cerebrovascular diseases (OR 2.464, 95% CI 0.755-8.044; p=0.007), CD3+CD8+ T-cells ≤75 cells·μL–1 (OR 3.982, 95% CI 1.132-14.006; p<0.001) and cardiac troponin I ≥0.05 ng·mL–1 (OR 4.077, 95% CI 1.166-14.253; p<0.001) were associated with an increase in risk of mortality from COVID-19 pneumonia. In a sex-, age- and comorbid illness-matched case–control study, CD3+CD8+ T-cells ≤75 cells·μL–1 and cardiac troponin I ≥0.05 ng·mL–1 remained as predictors for high mortality from COVID-19 pneumonia.

We identified four risk factors: age ≥65 years, pre-existing concurrent cardiovascular or cerebrovascular diseases, CD3+CD8+ T-cells ≤75 cells·μL–1 and cardiac troponin I ≥0.05 ng·mL–1. The latter two factors, especially, were predictors for mortality of COVID-19 pneumonia patients.




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No association of COVID-19 transmission with temperature or UV radiation in Chinese cities

The coronavirus disease 2019 (COVID-19) epidemic, which was first reported in December 2019 in Wuhan, China, has caused 80 904 confirmed cases as of 9 March 2020, with 28 673 cases being reported outside of China. It has been declared a pandemic by the World Health Organization (WHO), has exhibited human-to-human transmissibility and has spread rapidly across countries [1]. Although the Chinese government has taken various measures to control city-to-city transmission (e.g. shutting down cities, extending holidays) and many other countries have implemented measures (such as airport screening and testing patients who have reported symptoms), the number of cases is still increasing quickly throughout the world.




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The ERS approach to e-cigarettes is entirely rational

The call for the European Respiratory Society (ERS) to change their e-cigarette and vaping policy, from honourable people with decades of experience fighting the evils of tobacco, is unfortunately misconceived. The three issues of greatest concern are acute toxicity, chronic toxicity and, most importantly, the effects on children and young people. The efficacy of e-cigarettes as an adjunct to smoking cessation are outwith the expertise of paediatric specialists, but we would ask for assurances that any benefits really do outweigh the risks to children and young people (below). Our comments on these key issues are as follows:




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A rational approach to e-cigarettes: challenging ERS policy on tobacco harm reduction

We wish to thank J. Britton and co-workers for responding to our editorial and giving us an opportunity to clarify our position as well as correct a few misunderstandings. We definitely share the same goal, which is to relieve Europe and the rest of the world from the terrible results of the tobacco epidemic. We also do not "blankly oppose e-cigarettes"; however, we strongly advocate against a harm reduction strategy including e-cigarettes as well as heated tobacco products [1]. As clinicians we all see reluctant smokers where e-cigarettes can be tried as a last resort for getting off cigarette smoking, but that is of little relevance for a general harm reduction strategy. We also agree that the UK has achieved a lot in the area of smoking cessation but would argue that this has been achieved by impressive tobacco control, not by the use of e-cigarettes, and that a country such as Australia, which has banned nicotine-containing e-cigarettes, has achieved similar results.




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What constitutes a "clinically significant" bronchodilator response in children?

We read with great interest the recent paper of de Jong et al. [1] evaluating the contribution of a detailed history and a variety of diagnostic tests, including spirometry and bronchodilator tests, to diagnosing asthma in 111 children. In the methodology section, with regard to their definition of a "clinically significant" bronchodilator responsiveness (BDR), the authors only considered the forced expiratory volume in 1 s (FEV1) and applied the following two thresholds: ≥10% increase (no reference was cited) and ≥12% increase (according to the National Institute for Health and Care Excellence (NICE) [2]). Their approach could be a source of confusion for at least three reasons.




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A rational approach to e-cigarettes: challenging ERS policy on tobacco harm reduction

The respiratory community is united in its desire to reduce and eliminate the harm caused by tobacco smoking, which is at present on course to kill one billion people in the 21st century. The stated policy of the European Respiratory Society is to strive "constantly to promote strong and evidence-based policies to reduce the burden of tobacco related diseases". In our view, the recent ERS Tobacco Control Committee statement on tobacco harm reduction [1], though well-intentioned, appears to be based on a number of false premises and draws its conclusions from a partial account of available data. It also presents a false dichotomy between the provision of "conventional" tobacco control and harm reduction approaches. We therefore respond, in turn, to the seven arguments presented against the adoption of harm reduction in the Committee's statement.




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Adherence to corticosteroids and clinical outcomes in mepolizumab therapy for severe asthma

Introduction

Inhaled corticosteroids (ICS) achieve disease control in the majority of asthmatic patients, although adherence to prescribed ICS is often poor. Patients with severe eosinophilic asthma may require treatment with oral corticosteroids (OCS) and/or biologic agents such as mepolizumab. It is unknown if ICS adherence changes on, or alters clinical response to, biologic therapy.

Methods

We examined ICS adherence and clinical outcomes in OCS-dependent severe eosinophilic asthma patients who completed 1 year of mepolizumab therapy. The ICS medicines possession ratio (MPR) was calculated (the number of doses of ICS issued on prescription/expected number) for the year before and the year after biologic initiation. Good adherence was defined as MPR >0.75, intermediate 0.74–0.51 and poor <0.5. We examined outcomes after 12 months of biologic therapy, including OCS reduction and annualised exacerbation rate (AER), stratified by adherence to ICS on mepolizumab.

Results

Out of 109 patients commencing mepolizumab, 91 who had completed 12 months of treatment were included in the final analysis. While receiving mepolizumab, 68% had good ICS adherence, with 16 (18%) having poor ICS adherence. ICS use within the cohort remained similar before (MPR 0.81±0.32) and during mepolizumab treatment (0.82±0.32; p=0.78). Patients with good adherence had greater reductions in OCS dose (median (interquartile range) OCS reduction 100 (74–100)% versus 60 (27–100)%; p=0.031) and exacerbations (AER change –2.1±3.1 versus 0.3±2.5; p=0.011) than those with poor adherence. Good ICS adherence predicted the likelihood of stopping maintenance OCS (adjusted OR 3.19, 95% CI 1.02–9.94; p=0.045).

Conclusion

ICS nonadherence is common in severe eosinophilic asthma patients receiving mepolizumab, and is associated with a lesser reduction in OCS requirements and AER.




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Magnetic resonance imaging of pulmonary arterial compliance after pulmonary endarterectomy

Pulmonary endarterectomy (PEA) is the treatment of choice of chronic thromboembolic pulmonary hypertension (CTEPH) [1]. However, successfully operated patients may continue to suffer from dyspnoea and limitation of exercise capacity, despite improvement or even normalisation of pulmonary artery pressure (PAP), cardiac output (CO) and pulmonary vascular resistance (PVR) [2]. This absence of complete symptomatic recovery has been explained by a decreased right ventricular (RV) function reserve due to persistent increased afterload [3, 4], related to decreased pulmonary arterial compliance (PCa) more than to mildly increased PVR [5, 6]. There is therefore interest in assessing PCa in patients during the follow-up of PEA.




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Obstructive sleep apnoea treatment and blood pressure: which phenotypes predict a response? A systematic review and meta-analysis

The treatment for obstructive sleep apnoea (OSA) with continuous positive airway pressure (CPAP) or mandibular advancement devices (MADs) is associated with blood pressure (BP) reduction; however, the overall effect is modest. The aim of this systematic review and meta-analysis of randomised controlled trials (RCTs) comparing the effect of such treatments on BP was to identify subgroups of patients who respond best to treatment.

The article search was performed in three different databases with specific search terms and selection criteria. From 2289 articles, we included 68 RCTs that compared CPAP or MADs with either passive or active treatment. When all the studies were pooled together, CPAP and MADs were associated with a mean BP reduction of –2.09 (95% CI –2.78– –1.40) mmHg for systolic BP and –1.92 (95% CI –2.40– –1.43) mmHg for diastolic BP and –1.27 (95% CI –2.34– –0.20) mmHg for systolic BP and –1.11 (95% CI –1.82– –0.41) mmHg for diastolic BP, respectively. The subgroups of patients who showed a greater response were those aged <60 years (systolic BP –2.93 mmHg), with uncontrolled BP at baseline (systolic BP –4.14 mmHg) and with severe oxygen desaturations (minimum arterial oxygen saturation measured by pulse oximetry <77%) at baseline (24-h systolic BP –7.57 mmHg).

Although this meta-analysis shows that the expected reduction of BP by CPAP/MADs is modest, it identifies specific characteristics that may predict a pronounced benefit from CPAP in terms of BP control. These findings should be interpreted with caution; however, they are particularly important in identifying potential phenotypes associated with BP reduction in patients treated for OSA.




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Dissimilarity of the gut-lung axis and dysbiosis of the lower airways in ventilated preterm infants

Background

Chronic lung disease of prematurity (CLD), also called bronchopulmonary dysplasia, is a major consequence of preterm birth, but the role of the microbiome in its development remains unclear. Therefore, we assessed the progression of the bacterial community in ventilated preterm infants over time in the upper and lower airways, and assessed the gut–lung axis by comparing bacterial communities in the upper and lower airways with stool findings. Finally, we assessed whether the bacterial communities were associated with lung inflammation to suggest dysbiosis.

Methods

We serially sampled multiple anatomical sites including the upper airway (nasopharyngeal aspirates), lower airways (tracheal aspirate fluid and bronchoalveolar lavage fluid) and the gut (stool) of ventilated preterm-born infants. Bacterial DNA load was measured in all samples and sequenced using the V3–V4 region of the 16S rRNA gene.

Results

From 1102 (539 nasopharyngeal aspirates, 276 tracheal aspirate fluid, 89 bronchoalveolar lavage, 198 stool) samples from 55 preterm infants, 352 (32%) amplified suitably for 16S RNA gene sequencing. Bacterial load was low at birth and quickly increased with time, but was associated with predominant operational taxonomic units (OTUs) in all sample types. There was dissimilarity in bacterial communities between the upper and lower airways and the gut, with a separate dysbiotic inflammatory process occurring in the lower airways of infants. Individual OTUs were associated with increased inflammatory markers.

Conclusions

Taken together, these findings suggest that targeted treatment of the predominant organisms, including those not routinely treated, such as Ureaplasma spp., may decrease the development of CLD in preterm-born infants.




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Forced oscillation technique for optimising PEEP in ventilated extremely preterm infants

Ventilatory settings are critical in mechanically ventilated extremely preterm newborn infants due to the risk of ventilation-induced lung injury (VILI) and the subsequent development of bronchopulmonary dysplasia (BPD) [1]. Positive end-expiratory pressure (PEEP) settings usually rely on blood gases, oxygen requirement, lung auscultation, evaluation of chest radiograph and assessment of the pressure/volume curves provided by ventilators. Studies of optimal PEEP settings in the surfactant-treated preterm infant in need of mechanical ventilation are limited and evidence-based clinical guidelines are sparse [2, 3]. A bedside method identifying the PEEP value that comprises maximal lung volume recruitment and minimising tissue overdistension could improve real-time optimisation of PEEP and potentially minimise the risk of VILI and BPD [4, 5].




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European Respiratory Journal




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Immediate reactions with glatiramer acetate: Diagnosis of allergy and desensitization protocols

Purpose of review

Diverse adverse events have been associated with administration of glatiramer acetate (GA), mainly local reactions at the injection site. Other, less frequent generalized reactions include isolated postinjection reactions and anaphylaxis, which may lead to discontinuation of GA.

Recent findings

Close collaboration between the allergy and neurology departments is needed to study adverse reactions to GA. The allergy study should include a detailed history and skin prick and intradermal tests with GA and, if possible, determination of specific IgE levels. Furthermore, the implication of other drugs should be ruled out.

Summary

An accurate diagnosis of reactions to GA is essential if we are to confirm or rule out allergy to GA. When an allergy diagnosis is confirmed or firmly suspected based on clinical evidence, desensitization protocols are increasingly seen as safe methods for reintroduction of GA.




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Neurology consults in emergency departments: Opportunities to streamline care

Objective

To use the variations in neurology consultations requested by emergency department (ED) physicians to identify opportunities to implement multidisciplinary interventions in an effort to reduce ED overcrowding.

Methods

We retrospectively analyzed ED visits across 3 urban hospitals to determine the top 10 most common chief complaints leading to neurology consultation. For each complaint, we evaluated the likelihood of consultation, admission rate, admitting services, and provider-to-provider variability of consultation.

Results

Of 145,331 ED encounters analyzed, 3,087 (2.2%) involved a neurology consult, most commonly with chief complaints of acute-onset neurologic deficit, subacute neurologic deficit, or altered mental status. ED providers varied most in their consultation for acute-onset neurologic deficit, dizziness, and headache. Neurology consultation was associated with a 2.3-hour-longer length of stay (LOS) (95% CI: 1.6–3.1). Headache in particular has an average of 6.7-hour-longer ED LOS associated with consultation, followed by weakness or extremity weakness (4.4 hours) and numbness (4.1 hours). The largest estimated cumulative difference (number of patients with the specific consultation multiplied by estimated difference in LOS) belongs to headache, altered mental status, and seizures.

Conclusion

A systematic approach to identify variability in neurology consultation utilization and its effect on ED LOS helps pinpoint the conditions most likely to benefit from protocolized pathways.




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Ataxic-hypotonic cerebral palsy in a cerebral palsy registry: Insights into a distinct subtype

Objective

To specifically report on ataxic-hypotonic cerebral palsy (CP) using registry data and to directly compare its features with other CP subtypes.

Methods

Data on prenatal, perinatal, and neonatal characteristics and gross motor function (Gross Motor Function Classification System [GMFCS]) and comorbidities in 35 children with ataxic-hypotonic CP were extracted from the Canadian Cerebral Palsy Registry and compared with 1,804 patients with other subtypes of CP.

Results

Perinatal adversity was detected significantly more frequently in other subtypes of CP (odds ratio [OR] 4.3, 95% confidence interval [CI] 1.5–11.7). The gestational age at birth was higher in ataxic-hypotonic CP (median 39.0 weeks vs 37.0 weeks, p = 0.027). Children with ataxic-hypotonic CP displayed more intrauterine growth restriction (OR 2.6, 95% CI 1.0–6.8) and congenital malformation (OR 2.4, 95% CI 1.2–4.8). MRI was more likely to be either normal (OR 3.8, 95% CI 1.4–10.5) or to show a cerebral malformation (OR 4.2, 95% CI 1.5–11.9) in ataxic-hypotonic CP. There was no significant difference in terms of GMFCS or the presence of comorbidities, except for more frequent communication impairment in ataxic-hypotonic CP (OR 4.2, 95% CI 1.5–11.6).

Conclusions

Our results suggest a predominantly genetic or prenatal etiology for ataxic-hypotonic CP and imply that a diagnosis of ataxic-hypotonic CP does not impart a worse prognosis with respect to comorbidities or functional impairment. This study contributes toward a better understanding of ataxic-hypotonic CP as a distinct nosologic entity within the spectrum of CP with its own pathogenesis, risk factors, clinical profile, and prognosis compared with other CP subtypes.




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Factors associated with 30-day readmission for patients hospitalized for seizures

Background

We sought to determine the cumulative incidence of readmissions after a seizure-related hospitalization and identify risk factors and readmission diagnoses.

Methods

We performed a retrospective cohort study of adult patients hospitalized with a primary discharge diagnosis of seizure (International Classification of Diseases, Ninth Edition, Clinical Modification codes 345.xx and 780.3x) using the State Inpatient Databases across 11 states from 2009 to 2012. Hospital and community characteristics were obtained from the American Hospital Association and Robert Wood Johnson Foundation. We performed logistic regressions to explore effects of patient, hospital, and community factors on readmissions within 30 days of discharge.

Results

Of 98,712 patients, 13,929 (14%) were readmitted within 30 days. Reasons for readmission included epilepsy/convulsions (30% of readmitted patients), mood disorders (5%), schizophrenia (4%), and septicemia (4%). The strongest predictors of readmission were diagnoses of CNS tumor (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.9–2.4) or psychosis (OR 1.8, 95% CI 1.7–1.8), urgent index admission (OR 2.0, 95% CI 1.8–2.2), transfer to nonacute facilities (OR 1.7, 95% CI 1.6–1.8), long length of stay (OR 1.7, 95% CI 1.6–1.8), and for-profit hospitals (OR 1.7, 95% CI 1.6–1.8). Our main model's c-statistic was 0.66. Predictors of readmission for status epilepticus included index admission for status epilepticus (OR 3.5, 95% CI 2.6–4.7), low hospital epilepsy volume (OR 0.4, 95% CI 0.3–0.7), and rural hospitals (OR 4.8, 95% CI 2.1–10.9).

Conclusion

Readmission is common after hospitalization for seizures. Prevention strategies should focus on recurrent seizures, the most common readmission diagnosis. Many factors were associated with readmission, although readmissions remain challenging to predict.




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Cerebral venous thrombosis: Associations between disease severity and cardiac markers

Background

Plasma cardiac troponin (cTn) elevation occurs in acute ischemic stroke and intracranial hemorrhage and can suggest a poor prognosis. Because acute cerebral venous thrombosis (CVT) might lead to venous stasis, which could result in cardiac stress, it is important to evaluate whether cTn elevation occurs in patients with CVT.

Methods

Inpatients at Johns Hopkins Hospital from 2005 to 2015 meeting the following criteria were included: CVT (ICD-9 codes with radiologic confirmation) and available admission electrocardiogram (ECG) and cTn level. In regression models, presence of ECG abnormalities and cTn elevation (>0.06 ng/mL) were evaluated as dependent variables in separate models, with location and severity of CVT involvement as independent variables, adjusted for age, sex, and hypertension.

Results

Of 81 patients with CVST, 53 (66%) met the inclusion criteria. Participants were, on average, aged 42 years, white (71%), and female (66%). The left transverse sinus was most commonly thrombosed (47%), with 66% having >2 veins thrombosed. Twenty-two (41%) had cTn elevation. Odds of cTn elevation increased per each additional vein thrombosed (adjusted OR 2.79, 95% CI [1.08–7.23]). Of those with deep venous involvement, 37.5% had cTn elevation compared with 4.4% without deep clots (p = 0.02). Venous infarction (n = 15) was associated with a higher mean cTn (0.14 vs 0.02 ng/mL, p = 0.009) and was predictive of a higher cTn in adjusted models (β = 0.15, 95% CI [0.06–0.25]).

Conclusions

In this single-center cohort study, markers of CVT severity were associated with increased odds of cTn elevation; further investigation is needed to elucidate causality and significance.




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Author response: Functional neurologic disorders: Bringing the informal and hidden curriculum to light

Dr. Sethi raises an excellent point about the term functional neurologic disorder (FND) in his comment on the editorial.1 It seems clear that reticence to use the term functional creates the ambiguity he mentions. Medically unexplained symptoms, categorized in the international classification of diseases as undifferentiated somatoform disorders, are a diagnosis that many providers are loathed to give. Whether that is because of concern about missing a diagnosis is not clear. Having evaluated and treated more than 400 of these individuals in the FND clinic at the University of Colorado, I can attest to the fact that patients arrive confused about their diagnosis. Multiple incorrect diagnoses, as Dr. Sethi points out, pack the medical histories of patients with FND, leading doctors and patients astray. I believe that the commentary by Perez et al.2 gives us the best chance for a way forward, by teaching a new generation of residents and fellows how to approach patients in a nonjudgmental and open-minded fashion. It took 30 years to add Functional Neurologic Disorder to the Diagnostic and Statistical Manual, and it is still parenthetical to the term Conversion.3 Stripping the diagnosis of FND of its stigma and empowering care providers to rule in functional disorders is an actionable step which should be taken.




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Reader response: Functional neurologic disorders: Bringing the informal and hidden curriculum to light

I read with interest the editorial by Strom1 about functional neurologic disorders (FNDs). As a treating physician, I have struggled with the multiple diagnostic labels attached to these patients by physicians of different medical specialties during the course of their clinical disease presentation. A neurologist may assign a patient who presents with chronic fatigue the diagnostic labels of narcolepsy, idiopathic hypersomnia, or chronic Lyme disease. A rheumatologist may assign the label of collagen vascular disease, and a psychiatrist may diagnose depression. This diagnostic ambiguity is troublesome for patients and clinicians alike. I contend that even the term FND needs to be revisited. A patient should be broadly labeled as having a functional disorder and only after characterization sublabeled and referred to an appropriate specialty physician.




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Author response: Symptom burden among individuals with Parkinson disease: A national survey

We appreciate the readers' comments on the prevalence and impact of apathy on quality of life among individuals with Parkinson disease. In constructing our survey instrument, we discussed the inclusion of apathy as a symptom. However, we ultimately opted against inclusion because of concerns about the specificity of terminology in our online survey. Patients and care partners may not be familiar with the term "apathy,"and near-synonyms such as "reduced motivation" have substantial overlap with other nonmotor features. Still, as the readers point out, apathy is extremely common and under-recognized. Similar to many of the nonmotor symptoms identified in our study,1 we agree that clinicians should be screening for apathy among those with Parkinson disease.




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Reader response: Symptom burden among individuals with Parkinson disease: A national survey

We read with great interest the study by Tarolli et al.,1 which explored the burden of disease in Parkinson disease (PD) by evaluating the prevalence of nonmotor symptoms and their association with quality of life. The authors selected nonmotor symptoms based on literature review, expert opinions, and patient interviews. We note that apathy, which has major consequences for patients and carers, was not included as a relevant nonmotor symptom in their study. We performed a subcohort analysis of 60 patients from a study of pain in PD in 110 outpatients (PaCoMo-study, registered trial number: NL6311402917 [toetsingonline.nl]). We retrospectively reviewed the medical records to check whether the clinician identified apathy in these patients in the previous year, which was the case in 15% of the patients (n = 9). Blind to those results, patients were examined with the Apathy Scale (AS).2 In total, 63.3% (n = 38) of the patients scored positive on the AS. Only 18.4% of the patients who scored positive on the AS were also classified or mentioned with apathy in the medical records by clinicians.




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Progressive supranuclear palsy and pawpaw

Consider consumption of annonacin-containing plant products, including pawpaw, as a possible environmental risk factor for atypical parkinsonism.




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Optimizing Resources in Childrens Surgical Care: An Update on the American College of Surgeons' Verification Program

Surgical procedures are performed in the United States in a wide variety of clinical settings and with variation in clinical outcomes. In May 2012, the Task Force for Children’s Surgical Care, an ad hoc multidisciplinary group comprising physicians representing specialties relevant to pediatric perioperative care, was convened to generate recommendations to optimize the delivery of children’s surgical care. This group generated a white paper detailing the consensus opinions of the involved experts. Following these initial recommendations, the American College of Surgeons (ACS), Children’s Hospital Association, and Task Force for Children’s Surgical Care, with input from all related perioperative specialties, developed and published specific and detailed resource and quality standards designed to improve children’s surgical care (https://www.facs.org/quality-programs/childrens-surgery/childrens-surgery-verification). In 2015, with the endorsement of the American Academy of Pediatrics (https://pediatrics.aappublications.org/content/135/6/e1538), the ACS established a pilot verification program. In January 2017, after completion of the pilot program, the ACS Children’s Surgery Verification Quality Improvement Program was officially launched. Verified sites are listed on the program Web site at https://www.facs.org/quality-programs/childrens-surgery/childrens-surgery-verification/centers, and more than 150 are interested in verification. This report provides an update on the ACS Children’s Surgery Verification Quality Improvement Program as it continues to evolve.




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Shellhaas RA, Burns JW, Barks JDE, Fauziya Hassan F, Chervin RD. Maternal Voice and Infant Sleep in the Neonatal Intensive Care Unit. Pediatrics. 2019;144(3):e30190288




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Initial Resuscitation Algorithm for Children