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1.
Article En | MEDLINE | ID: mdl-38635834

BACKGROUND: The anti-IgE monoclonal, omalizumab, is widely used for severe asthma. This study aimed to identify biomarkers that predict clinical improvement during one year of omalizumab treatment. METHODS: 1-year, open-label, Study of Mechanisms of action of Omalizumab in Severe Asthma (SoMOSA) involving 216 severe (GINA step 4/5) uncontrolled atopic asthmatics (≥2 severe exacerbations in previous year) on high-dose inhaled corticosteroids, long-acting ß-agonists, ± mOCS. It had two phases: 0-16 weeks, to assess early clinical improvement by Global Evaluation of Therapeutic Effectiveness (GETE), and 16-52 weeks, to assess late responses by ≥50% reduction in exacerbations or dose of maintenance oral corticosteroids (mOCS). All participants provided samples (exhaled breath, blood, sputum, urine) before and after 16 weeks of omalizumab treatment. RESULTS: 191 patients completed phase 1; 63% had early improvement. Of 173 who completed phase 2, 69% had reduced exacerbations by ≥50%, while 57% (37/65) on mOCS reduced their dose by ≥50%. The primary outcome 2, 3-dinor-11-ß-PGF2α, GETE and standard clinical biomarkers (blood and sputum eosinophils, exhaled nitric oxide, serum IgE) did not predict either clinical response. Five breathomics (GC-MS) and 5 plasma lipid biomarkers strongly predicted the ≥50% reduction in exacerbations (receiver operating characteristic area under the curve (AUC): 0.780 and 0.922, respectively) and early responses (AUC:0.835 and 0.949, respectively). In independent cohorts, the GC-MS biomarkers differentiated between severe and mild asthma. Conclusions This is the first discovery of omics biomarkers that predict improvement to a biologic for asthma. Their prospective validation and development for clinical use is justified. This article is open access and distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/).

2.
Article En | MEDLINE | ID: mdl-38520148

The cell's ability to change shape is a central feature in many cellular processes, including cytokinesis, motility, migration, and tissue formation. The cell constructs a network of contractile proteins underneath the cell membrane to form the cortex, and the reorganization of these components directly contributes to cellular shape changes. The desire to mimic these cell shape changes to aid in the creation of a synthetic cell has been increasing. Therefore, membrane-based reconstitution experiments have flourished, furthering our understanding of the minimal components the cell uses throughout these processes. Although biochemical approaches increased our understanding of actin, myosin II, and actin-associated proteins, using membrane-based reconstituted systems has further expanded our understanding of actin structures and functions because membrane-cortex interactions can be analyzed. In this review, we highlight the recent developments in membrane-based reconstitution techniques. We examine the current findings on the minimal components needed to recapitulate distinct actin structures and functions and how they relate to the cortex's impact on cellular mechanical properties. We also explore how co-processing of computational models with wet-lab experiments enhances our understanding of these properties. Finally, we emphasize the benefits and challenges inherent to membrane-based, reconstitution assays, ranging from the advantage of precise control over the system to the difficulty of integrating these findings into the complex cellular environment.

3.
bioRxiv ; 2024 Feb 13.
Article En | MEDLINE | ID: mdl-38405988

To move through complex environments, cells must constantly integrate chemical and mechanical cues. Signaling networks, such as those comprising Ras and PI3K, transmit chemical cues to the cytoskeleton, but the cytoskeleton must also relay mechanical information back to those signaling systems. Using novel synthetic tools to acutely control specific elements of the cytoskeleton in Dictyostelium and neutrophils, we delineate feedback mechanisms that alter the signaling network and promote front- or back-states of the cell membrane and cortex. First, increasing branched actin assembly increases Ras/PI3K activation while reducing polymeric actin levels overall decreases activation. Second, reducing myosin II assembly immediately increases Ras/PI3K activation and sensitivity to chemotactic stimuli. Third, inhibiting branched actin alone increases cortical actin assembly and strongly blocks Ras/PI3K activation. This effect is mitigated by reducing filamentous actin levels and in cells lacking myosin II. Finally, increasing actin crosslinking with a controllable activator of cytoskeletal regulator RacE leads to a large decrease in Ras activation both globally and locally. Curiously, RacE activation can trigger cell spreading and protrusion with no detectable activation of branched actin nucleators. Taken together with legacy data that Ras/PI3K promotes branched actin assembly and myosin II disassembly, our results define front- and back-promoting positive feedback loops. We propose that these loops play a crucial role in establishing cell polarity and mediating signal integration by controlling the excitable state of the signal transduction networks in respective regions of the membrane and cortex. This interplay enables cells to navigate intricate topologies like tissues containing other cells, the extracellular matrix, and fluids.

4.
Am J Physiol Heart Circ Physiol ; 326(3): H563-H567, 2024 Mar 01.
Article En | MEDLINE | ID: mdl-38214901

Earning an advanced degree in biomedical sciences can be a challenging experience, and recent data indicate high levels of stress and anxiety among the current generation of learners. We propose here a new illustration for all graduate students to visualize their didactic journey as a coronation process. Before their coronation, trainees must undergo rigorous preparation. During the training, four key attributes, best described by the acronym COST (Credibility, Opportunity, Strength, and Tenacity), are cultivated. Throughout their academic journey, which is a critical period of intellectual and personal growth, the trainees will enhance their understanding of the responsibility of wearing a CROWN, which requires accepting the Cost of earning a diadem, Revolutionizing their thought construct, being Open to innovation and research, acknowledging that Wealth is intrinsically connected to their health, and Never forsaking their aspiration and pursuits. Executing these principles daily will provide a mechanism on which to rise to the stature of achieving individual career goals (i.e., being a Regent of your life). Actualization of this process requires sacrifice, maturity, and a sense of fearlessness. The results of taking this approach will lead to an educational legacy that establishes a pattern of academic success that can be emulated by future learners.

5.
J Asthma ; 61(3): 177-183, 2024 Mar.
Article En | MEDLINE | ID: mdl-37668326

OBJECTIVES: Chronic rhinosinusitis (CRS) with severe asthma are associated with breathing pattern disorder (BPD). Mouth breathing is a sign of breathing pattern disorder, and nose breathing a fundamental part of breathing pattern retraining for BPD. The prevalence of BPD in relation to CRS subtypes and the relationship of nasal obstruction to BPD in CRS and associated severe asthma is unknown. The breathing pattern assessment tool (BPAT) can identify BPD. Our objective was to thus investigate the prevalence of BPD, nasal airflow obstruction and measures of airway disease severity in CRS with (CRSwNP) and without nasal polyps (CRSsNP) in severe asthma. METHODS: We determined whether CRS status, peak nasal inspiratory flow (PNIF) or polyp disease increased BPD prevalence. Demographic factors, measures of airway function and breathlessness in relation to BPD status and CRS subtypes were also evaluated. RESULTS: 130 Patients were evaluated (n = 69 had BPD). The prevalence of BPD in CRS with severe asthma was 53.1%. There was no difference between BPD occurrence between CRSwNP and CRSsNP. The mean polyp grade and PNIF were not statistically different between the BPD and non-BPD group. The presence of nasal polyps did not increase breathlessness. CONCLUSIONS: BPD and CRS are commonly co-associated. CRS status and nasal obstruction per se does not increase BPD prevalence.


Asthma , Nasal Obstruction , Nasal Polyps , Rhinitis , Rhinosinusitis , Sinusitis , Humans , Nasal Polyps/complications , Nasal Polyps/epidemiology , Nasal Polyps/diagnosis , Asthma/complications , Asthma/epidemiology , Prevalence , Nasal Obstruction/epidemiology , Nasal Obstruction/complications , Rhinitis/complications , Sinusitis/complications , Chronic Disease , Dyspnea , Respiration
7.
bioRxiv ; 2023 Sep 23.
Article En | MEDLINE | ID: mdl-37790449

Non-linear biomolecular interactions on the membranes drive membrane remodeling that underlies fundamental biological processes including chemotaxis, cytokinesis, and endocytosis. The multitude of biomolecules, the redundancy in their interactions, and the importance of spatiotemporal context in membrane organization hampers understanding the physical principles governing membrane mechanics. A minimal, in vitro system that models the functional interactions between molecular signaling and membrane remodeling, while remaining faithful to cellular physiology and geometry is powerful yet remains unachieved. Here, inspired by the biophysical processes underpinning chemotaxis, we reconstituted externally-controlled actin polymerization inside giant unilamellar vesicles, guiding self-organization on the membrane. We show that applying undirected external chemical inputs to this system results in directed actin polymerization and membrane deformation that are uncorrelated with upstream biochemical cues, indicating symmetry breaking. A biophysical model of the dynamics and mechanics of both actin polymerization and membrane shape suggests that inhomogeneous distributions of actin generate membrane shape deformations in a non-linear fashion, a prediction consistent with experimental measurements and subsequent local perturbations. The active protocellular system demonstrates the interplay between actin dynamics and membrane shape in a symmetry breaking context that is relevant to chemotaxis and a suite of other biological processes.

8.
Mol Biol Cell ; 34(7): ar71, 2023 06 01.
Article En | MEDLINE | ID: mdl-37074945

Nonmuscle myosin IIB (NMIIB) is considered a primary force generator during cell motility. Yet many cell types, including motile cells, do not necessarily express NMIIB. Given the potential of cell engineering for the next wave of technologies, adding back NMIIB could be a strategy for creating supercells with strategically altered cell morphology and motility. However, we wondered what unforeseen consequences could arise from such an approach. Here, we leveraged pancreatic cancer cells, which do not express NMIIB. We generated a series of cells where we added back NMIIB and strategic mutants that increase the ADP-bound time or alter the phosphorylation control of bipolar filament assembly. We characterized the cellular phenotypes and conducted RNA-seq analysis. The addition of NMIIB and the different mutants all have specific consequences for cell morphology, metabolism, cortical tension, mechanoresponsiveness, and gene expression. Major modes of ATP production are shifted, including alterations in spare respiratory capacity and the dependence on glycolysis or oxidative phosphorylation. Several metabolic and growth pathways undergo significant changes in gene expression. This work demonstrates that NMIIB is highly integrated with many cellular systems and simple cell engineering has a profound impact that extends beyond the primary contractile activity presumably being added to the cells.


Nonmuscle Myosin Type IIA , Nonmuscle Myosin Type IIB , Nonmuscle Myosin Type IIB/metabolism , Cellular Reprogramming , Cytoskeleton/metabolism , Muscle Contraction , Phosphorylation , Nonmuscle Myosin Type IIA/metabolism
9.
J Allergy Clin Immunol Pract ; 11(4): 1233-1242.e5, 2023 04.
Article En | MEDLINE | ID: mdl-36621603

BACKGROUND: Approximately 5% to 10% of patients with asthma have severe disease, with a consistent preponderance in females. Current asthma guidelines recommend stepwise treatment to achieve symptom control with no differential treatment considerations for either sex. OBJECTIVE: To examine whether patient sex affects outcomes when using a composite T2-biomarker score to adjust corticosteroid (CS) treatment in patients with severe asthma compared with standard care. METHODS: This is a post hoc analysis, stratifying patient outcomes by sex, of a 48-week, multicenter, randomized controlled clinical trial comparing a biomarker-defined treatment algorithm with standard care. The primary outcome was the proportion of patients with a reduction in CS treatment (inhaled and oral corticosteroids). Secondary outcomes included exacerbation rates, hospital admissions, and lung function. RESULTS: Of the 301 patients randomized, 194 (64.5%) were females and 107 (35.5%) were males. The biomarker algorithm led to a greater proportion of females being on a lower CS dose versus standard care, which was not seen in males (effect estimate: females, 3.57; 95% CI, 1.14-11.18 vs males, 0.54; 95% CI, 0.16-1.80). In T2-biomarker-low females, reducing CS dose was not associated with increased exacerbations. Females scored higher in all domains of the 7-item Asthma Control Questionnaire, apart from FEV1, but with no difference when adjusted for body mass index/anxiety and/or depression. Dissociation between symptoms and T2 biomarkers were noted in both sexes, with a higher proportion of females being symptom high/T2-biomarker low (22.8% vs 15.6%; P = .0002), whereas males were symptom low/T2-biomarker high (22.3% vs 11.4%; P < .0001). CONCLUSIONS: This exploratory post hoc analysis identified that females achieved a greater benefit from biomarker-directed CS optimization versus symptom-directed treatment.


Anti-Asthmatic Agents , Asthma , Male , Female , Humans , Adrenal Cortex Hormones , Drug Therapy, Combination , Biomarkers
10.
Biophys J ; 121(23): 4600-4614, 2022 12 06.
Article En | MEDLINE | ID: mdl-36273263

Cell shape change processes, such as proliferation, polarization, migration, and cancer metastasis, rely on a dynamic network of macromolecules. The proper function of this network enables mechanosensation, the ability of cells to sense and respond to mechanical cues. Myosin II and cortexillin I, critical elements of the cellular mechanosensory machinery, preassemble in the cytoplasm of Dictyostelium cells into complexes that we have termed contractility kits (CKs). Two IQGAP proteins then differentially regulate the mechanoresponsiveness of the cortexillin I-myosin II elements within CKs. To investigate the mechanism of CK self-assembly and gain insight into possible molecular means for IQGAP regulation, we developed a coarse-grained excluded volume molecular model in which all protein polymers are represented by nm-sized spheres connected by spring-like links. The model is parameterized using experimentally measured parameters acquired through fluorescence cross-correlation spectroscopy and fluorescence correlation spectroscopy, which describe the interaction affinities and diffusion coefficients for individual molecular components, and which have also been validated via several orthogonal methods. Simulations of wild-type and null-mutant conditions implied that the temporal order of assembly of these kits is dominated by myosin II dimer formation and that IQGAP proteins mediate cluster growth. In addition, our simulations predicted the existence of "ambiguous" CKs that incorporate both classes of IQGAPs, and we confirmed this experimentally using fluorescence cross-correlation spectroscopy. The model serves to describe the formation of the CKs and how their assembly enables and regulates mechanosensation at the molecular level.


Dictyostelium
11.
J Cell Biol ; 221(11)2022 11 07.
Article En | MEDLINE | ID: mdl-36165849

Cellular functions, such as division and migration, require cells to undergo robust shape changes. Through their contractility machinery, cells also sense, respond, and adapt to their physical surroundings. In the cytoplasm, the contractility machinery organizes into higher order assemblies termed contractility kits (CKs). Using Dictyostelium discoideum, we previously identified Discoidin I (DscI), a classic secreted lectin, as a CK component through its physical interactions with the actin crosslinker Cortexillin I (CortI) and the scaffolding protein IQGAP2. Here, we find that DscI ensures robust cytokinesis through regulating intracellular components of the contractile machinery. Specifically, DscI is necessary for normal cytokinesis, cortical tension, membrane-cortex connections, and cortical distribution and mechanoresponsiveness of CortI. The dscI deletion mutants also have complex genetic epistatic relationships with CK components, acting as a genetic suppressor of cortI and iqgap1, but as an enhancer of iqgap2. This work underscores the fact that proteins like DiscI contribute in diverse ways to the activities necessary for optimal cell function.


Dictyostelium , Discoidins , Lectins , Actins/metabolism , Cytoplasm/metabolism , Dictyostelium/genetics , Dictyostelium/metabolism , Discoidins/metabolism , Lectins/metabolism , Microfilament Proteins , Protozoan Proteins/genetics , Protozoan Proteins/metabolism , ras GTPase-Activating Proteins/metabolism
12.
Allergy ; 77(11): 3362-3376, 2022 11.
Article En | MEDLINE | ID: mdl-35778780

BACKGROUND: In T2-mediated severe asthma, biologic therapies, such as mepolizumab, are increasingly used to control disease. Current biomarkers can indicate adequate suppression of T2 inflammation, but it is unclear whether they provide information about airway microbial composition. We investigated the relationships between current T2 biomarkers and microbial profiles, characteristics associated with a ProteobacteriaHIGH microbial profile and the effects of mepolizumab on airway ecology. METHODS: Microbiota sequencing was performed on sputum samples obtained at stable and exacerbation state from 140 subjects with severe asthma participating in two clinical trials. Inflammatory subgroups were compared on the basis of biomarkers, including FeNO and sputum and blood eosinophils. ProteobacteriaHIGH subjects were identified by Proteobacteria to Firmicutes ratio ≥0.485. Where paired sputum from stable visits was available, we compared microbial composition at baseline and following ≥12 weeks of mepolizumab. RESULTS: Microbial composition was not related to inflammatory subgroup based on sputum or blood eosinophils. FeNO ≥50 ppb when stable and at exacerbation indicated a group with less dispersed microbial profiles characterised by high alpha-diversity and low Proteobacteria. ProteobacteriaHIGH subjects were neutrophilic and had a longer time from asthma diagnosis than ProteobacteriaLOW subjects. In those studied, mepolizumab did not alter airway bacterial load or lead to increased Proteobacteria. CONCLUSION: High FeNO could indicate a subgroup of severe asthma less likely to benefit from antimicrobial strategies at exacerbation or in the context of poor control. Where FeNO is <50 ppb, biomarkers of microbial composition are required to identify those likely to respond to microbiome-directed strategies. We found no evidence that mepolizumab alters airway microbial composition.


Asthma , Humans , Asthma/diagnosis , Asthma/drug therapy , Asthma/microbiology , Eosinophils , Sputum/microbiology , Respiratory System/microbiology , Biomarkers
13.
Am J Respir Crit Care Med ; 206(5): 545-553, 2022 09 01.
Article En | MEDLINE | ID: mdl-35549845

Rationale: The past 25 years have seen huge progress in understanding of the pathobiology of type-2 (T2) asthma, identification of measurable biomarkers, and the emergence of novel monoclonal antibody treatments. Although present in a minority of patients with severe asthma, very little is known about the mechanisms underlying T2-low asthma, making it a significant unmet need in asthma research. Objectives: The objective of this study was to explore the differences between study exacerbators and nonexacerbators, to describe physiological changes at exacerbation in those who are T2HIGH and T2LOW at the time of exacerbation, and to evaluate the stability of inflammatory phenotypes when stable and at exacerbation. Methods: Exacerbation assessment was a prespecified secondary analysis of data from a 48-week, multicenter, randomized controlled clinical study comparing the use of biomarkers and symptoms to adjust steroid treatment in a T2-low severe asthma-enriched cohort. Participants were phenotyped as T2LOW (fractional exhaled nitric oxide ⩽ 20 ppb and blood eosinophil count ⩽ 150 cells/µl) or T2HIGH (fractional exhaled nitric oxide > 20 or blood eosinophil count > 150) at study enrollment and at each exacerbation. Here, we report the findings of the exacerbation analyses, including comparison of exacerbators and nonexacerbators, the physiological changes at exacerbation in those who had evidence of T2 biology at exacerbation versus those that did not, and the stability of inflammatory phenotypes when stable and at exacerbation. Measurements and Main Results: Of the 301 participants, 60.8% (183) had one or more self-reported exacerbations (total of 390). Exacerbators were more likely to be female, have a higher body mass index, and have more exacerbations requiring oral corticosteroid and unscheduled primary care attendances for exacerbations. At enrollment, 23.6% (71) were T2LOW and 76.4% (230) T2HIGH. The T2LOW group had more asthma primary care attendances, were more likely to have a previous admission to HDU (high dependency unit)/ICU and to be receiving maintenance oral corticosteroids. At exacerbation, the T2LOW events were indistinguishable from T2HIGH exacerbations in terms of lung function (mean fall in T2LOW FEV1, 200 [400] ml vs. T2HIGH 200 [300] ml; P = 0.93) and symptom increase (ACQ5: T2LOW, 1.4 [0.8] vs. T2HIGH, 1.3 [0.8]; P = 0.72), with no increase in T2 biomarkers from stable to exacerbation state in the T2LOW exacerbations. The inflammatory phenotype within individual patients was dynamic; inflammatory phenotype at study entry did not have a significant association with exacerbation phenotype. Conclusions: Asthma exacerbations demonstrating a T2LOW phenotype were physiologically and symptomatically similar to T2HIGH exacerbations. T2LOW asthma was an unstable phenotype, suggesting that exacerbation phenotyping should occur at the time of exacerbation. The clinically significant exacerbations in participants without evidence of T2 biology at the time of exacerbation highlight the unmet and pressing need to further understand the mechanisms at play in non-T2 asthma. Clinical trial registered with www.clinicaltrials.gov (NCT02717689).


Anti-Asthmatic Agents , Asthma , Adrenal Cortex Hormones/therapeutic use , Anti-Asthmatic Agents/therapeutic use , Biomarkers , Disease Progression , Female , Humans , Male , Phenotype , Risk Factors
14.
Biophys J ; 121(19): 3573-3585, 2022 10 04.
Article En | MEDLINE | ID: mdl-35505610

With the number of cancer cases projected to significantly increase over time, researchers are currently exploring "nontraditional" research fields in the pursuit of novel therapeutics. One emerging area that is steadily gathering interest revolves around cellular mechanical machinery. When looking broadly at the physical properties of cancer, it has been debated whether a cancer could be defined as either stiffer or softer across cancer types. With numerous articles supporting both sides, the evidence instead suggests that cancer is not particularly regimented. Instead, cancer is highly adaptable, allowing it to endure the constantly changing microenvironments cancer cells encounter, such as tumor compression and the shear forces in the vascular system and body. What allows cancer cells to achieve this adaptability are the particular proteins that make up the mechanical network, leading to a particular mechanical program of the cancer cell. Coincidentally, some of these proteins, such as myosin II, α-actinins, filamins, and actin, have either altered expression in cancer and/or some type of direct involvement in cancer progression. For this reason, targeting the mechanical system as a therapeutic strategy may lead to more efficacious treatments in the future. However, targeting the mechanical program is far from trivial. As involved as the mechanical program is in cancer development and metastasis, it also helps drive many other key cellular processes, such as cell division, cell adhesion, metabolism, and motility. Therefore, anti-cancer treatments targeting the mechanical program must take great care to avoid potential side effects. Here, we introduce the potential of targeting the mechanical program while also providing its challenges and shortcomings as a strategy for cancer treatment.


Actins , Neoplasms , Actinin , Actins/metabolism , Filamins , Humans , Myosin Type II/metabolism , Neoplasms/pathology , Tumor Microenvironment
15.
Front Oncol ; 12: 809179, 2022.
Article En | MEDLINE | ID: mdl-35174086

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest cancers due to low therapeutic response rates and poor prognoses. Majority of patients present with symptoms post metastatic spread, which contributes to its overall lethality as the 4th leading cause of cancer-related deaths. Therapeutic approaches thus far target only one or two of the cancer specific hallmarks, such as high proliferation rate, apoptotic evasion, or immune evasion. Recent genomic discoveries reveal that genetic heterogeneity, early micrometastases, and an immunosuppressive tumor microenvironment contribute to the inefficacy of current standard treatments and specific molecular-targeted therapies. To effectively combat cancers like PDAC, we need an innovative approach that can simultaneously impact the multiple hallmarks driving cancer progression. Here, we present the mechanical properties generated by the cell's cortical cytoskeleton, with a spotlight on PDAC, as an ideal therapeutic target that can concurrently attack multiple systems driving cancer. We start with an introduction to cancer cell mechanics and PDAC followed by a compilation of studies connecting the cortical cytoskeleton and mechanical properties to proliferation, metastasis, immune cell interactions, cancer cell stemness, and/or metabolism. We further elaborate on the implications of these findings in disease progression, therapeutic resistance, and clinical relapse. Manipulation of the cancer cell's mechanical system has already been shown to prevent metastasis in preclinical models, but it has greater potential for target exploration since it is a foundational property of the cell that regulates various oncogenic behaviors.

16.
Eur Respir J ; 59(4)2022 04.
Article En | MEDLINE | ID: mdl-34561291

BACKGROUND: Understanding why patients with severe asthma do not follow healthcare provider (HCP) advice to adjust treatment is critical to achieving personalised disease management. METHODS: We reviewed patient choice to follow HCP advice to adjust asthma treatment in a UK-based randomised, controlled, single-blind (study participant), multicentre, parallel group 48-week clinical study comparing biomarker-directed treatment adjustment with standard care in severe asthma. RESULTS: Of 1572 treatment advisories (291 participants), instructions were followed in 1377 cases (87.6%). Patients were more likely to follow advice to remain on treatment (96.7%) than to either reduce (70.3%) or increase (67.1%) their treatment, with 64% of patients following all treatment advice. Multivariate analysis associated belonging to an ethnic minority group (OR 3.10, 95% CI 1.68-5.73) and prior study medication changes (two or more changes: OR 2.77, 95% CI 1.51-5.10) with failure to follow treatment advice. In contrast, emergency room attendance in the prior year (OR 0.54, 95% CI 0.32-0.92) was associated with following treatment advice. The largest effect was seen with transition onto or off oral corticosteroids (OR 29.28, 95% CI 16.07-53.36) when compared with those requested to maintain treatment. Centre was also an important determinant regarding the likelihood of patients to follow treatment advice. CONCLUSIONS: Belonging to an ethnic minority group and multiple prior treatment adjustments were associated with not following HCP treatment advice. Patients also responded differently to HCP advice across UK specialist centres. These findings have implications for the generalisability of models of care in severe asthma and require further focused studies.


Asthma , Ethnicity , Adrenal Cortex Hormones/therapeutic use , Asthma/drug therapy , Humans , Minority Groups , Single-Blind Method
17.
Emerg Med Pract ; 23(12): 1-28, 2021 Dec.
Article En | MEDLINE | ID: mdl-34787992

Acute aortic syndromes include aortic dissection, penetrating atherosclerotic ulcer, and intramural hematomas, but aortic dissection is the most common and the deadliest. This review summarizes the latest evidence on developing a differential for aortic dissection when common complaints, such as chest pain, abdominal pain, and syncope are also present. Recent evidence on the optimal uses of emergency department imaging studies and risk stratification tools are reviewed, along with special considerations in the management of penetrating atherosclerotic ulcer and intramural hematoma. Pharmacologic therapies for managing hemodynamic parameters and shock, and indications for operative intervention are also reviewed, along with cutting-edge diagnostic and treatment options on the horizon.


Aortic Dissection , Aortic Dissection/diagnosis , Aortic Dissection/therapy , Emergency Service, Hospital , Hematoma/diagnosis , Hematoma/therapy , Humans , Syndrome , Ulcer
18.
Biophys J ; 120(22): 4905-4917, 2021 11 16.
Article En | MEDLINE | ID: mdl-34687718

Computational models of cell mechanics allow the precise interrogation of cell shape change. These morphological changes are required for cells to survive in diverse tissue environments. Here, we present a mesoscale mechanical model of cell-substrate interactions using the level set method based on experimentally measured parameters. By implementing a viscoelastic mechanical equivalent circuit, we accurately model whole-cell deformations that are important for a variety of cellular processes. To effectively model shape changes as a cell interacts with a substrate, we have included receptor-mediated adhesion, which is governed by catch-slip bond behavior. The effect of adhesion was explored by subjecting cells to a variety of different substrates including flat, curved, and deformable surfaces. Finally, we increased the accuracy of our simulations by including a deformable nucleus in our cells. This model sets the foundation for further exploration into computational analyses of multicellular interactions.


Cell Communication , Cell Nucleus , Cell Adhesion , Cell Shape , Stress, Mechanical
19.
Clin Transl Allergy ; 11(1): e12002, 2021 Mar.
Article En | MEDLINE | ID: mdl-33900051

BACKGROUND: Chronic rhinosinusitis (CRS) has a high prevalence of anxiety and depression. It is currently uncertain if treatment in patients with CRS with or without nasal polyps (CRSwNP and CRSsNP) has any impact on improving mental health outcomes. The aims here were to document anxiety and depression in patients with severe CRS and asthma already treated with appropriate medical therapy. We then evaluated whether further maximal treatment with omalizumab improved anxiety and/or depression alongside improvements in CRS and coassociated asthma. METHODS: Hospital Anxiety and Depression Scale (HADS) scores along with measures of CRS and asthma severity were recorded according to CRSwNP and CRSsNP status in n = 95 patients with severe CRS and asthma. Of this group, a further n = 23 had omalizumab for associated allergic asthma. Follow-up measures were collected 16 weeks after omalizumab treatment. RESULTS: HADS anxiety and depression prevalence in CRS were 49.47 % and 38.95%, respectively. Within the CRSwNP and CRSsNP group 53.06% and 45.66% had raised HADS-anxiety scores. Abnormal HADS-depression scores were present in 40.82% and 36.95% of the CRSwNP and CRSsNP groups, respectively. Correlations for sinonasal outcome test-22 (SNOT-22) versus HADS total was r = 0.59 p < 0.0001, HADS-anxiety r = 0.56 p < 0.0001 and HADS-depression r = 0.49 p < 0.0001. Omalizumab improved anxiety in CRS (p < 0.0001) regardless of nasal polyp status (CRSwNP p = 0.0042 and CRSsNP p = 0.0078). Depression scores did not improve in either group. SNOT-22 (p = 0.0006), asthma control questionnaire-7 (p = 0.0019) and mini-asthma quality of life questionnaire including emotional function (p = 0.0003 and p = 0.0009, respectively) all improved in both subgroups. CONCLUSION: In CRS and asthma, anxiety scores but not depression improved after omalizumab treatment. Anxiety may be closely related to airway disease severity, but depression may be independent of airway disease itself. If so, a separate mental health care pathway is needed for CRS patients with depression.

20.
J Cell Sci ; 134(4)2021 02 25.
Article En | MEDLINE | ID: mdl-33526710

Airway hydration and ciliary function are critical to airway homeostasis and dysregulated in chronic obstructive pulmonary disease (COPD), which is impacted by cigarette smoking and has no therapeutic options. We utilized a high-copy cDNA library genetic selection approach in the amoeba Dictyostelium discoideum to identify genetic protectors to cigarette smoke. Members of the mitochondrial ADP/ATP transporter family adenine nucleotide translocase (ANT) are protective against cigarette smoke in Dictyostelium and human bronchial epithelial cells. Gene expression of ANT2 is reduced in lung tissue from COPD patients and in a mouse smoking model, and overexpression of ANT1 and ANT2 resulted in enhanced oxidative respiration and ATP flux. In addition to the presence of ANT proteins in the mitochondria, they reside at the plasma membrane in airway epithelial cells and regulate airway homeostasis. ANT2 overexpression stimulates airway surface hydration by ATP and maintains ciliary beating after exposure to cigarette smoke, both of which are key functions of the airway. Our study highlights a potential for upregulation of ANT proteins and/or of their agonists in the protection from dysfunctional mitochondrial metabolism, airway hydration and ciliary motility in COPD.This article has an associated First Person interview with the first author of the paper.


Dictyostelium , Pulmonary Disease, Chronic Obstructive , Dictyostelium/genetics , Epithelial Cells/metabolism , Humans , Lung , Mitochondria , Mitochondrial ADP, ATP Translocases/metabolism , Pulmonary Disease, Chronic Obstructive/genetics , Pulmonary Disease, Chronic Obstructive/metabolism
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