Summary
Background
Autophagy and neutrophil extracellular DNA traps (NETs) are implicated in asthma; however, their roles in asthma pathogenesis have not been elucidated.
Objectives
We compared ...autophagy and NET production levels from peripheral blood neutrophils (PBNs) of patients with severe asthma (SA) and non‐severe asthma (NSA). Additionally, we investigated the inflammatory effects of NETs on human airway epithelial cells (AECs) and peripheral blood eosinophils (PBEs).
Methods
Peripheral blood neutrophils from patients with SA (n = 30) and NSA (n = 38) were treated with interleukin (IL)‐8 (100 ng/mL). Autophagy (light chain 3‐II expression) and NET production levels were evaluated by Western blot, immunofluorescence microscopy, and PicoGreen assay. The effects of NETs on AECs were assessed by investigating cell death, cell detachment, expression of occludin and claudin‐1, and IL‐8 production; the effects of NETs on PBEs were examined by investigating the activation and release of eosinophil cationic protein (ECP) and eosinophil‐derived neurotoxin (EDN).
Results
Untreated and IL‐8‐treated PBNs from the SA group produced higher autophagy and NET levels compared with those from the NSA group (P < 0.01). IL‐8 increased autophagy and NET levels in PBNs from the SA group, but not from the NSA group. NET levels were correlated with autophagy levels in PBNs (P < 0.001). IL‐8‐induced NET production levels negatively were correlated with FEV1/FVC (r = −0.700, P = 0.016). NETs induced cell death, detachment, degradation of occludin and claudin‐1, and IL‐8 production from AECs. Higher levels of NET‐induced ECP and EDN were released from PBEs in SA compared with NSA groups.
Conclusions and Clinical Relevance
Neutrophil autophagy and NETs could enhance asthma severity by damaging airway epithelium and triggering inflammatory responses of AECs and PBEs. Modulating neutrophil autophagy and NET production may be a new target therapy for SA.
Quantification of rill erosion processes is of great importance in both model parameter estimations for process-based rill erosion models and in model performance verification. This study presents a ...mathematical method to determine a physics-based rill erosion process derived from the feedback relationship of transport capacity and detachment capacity. Experimental data sets were used to determine transport capacities under steep slope gradients of 15°, 20°, and 25° and the detachment capacities. The estimated transport and detachment capacities were then used to determine the sediment delivery processes under different hydraulic regimes. The sediment concentrations along the rill determined with the mathematical method were compared with the experimental measurements to verify the methodology and the mathematics. Results showed that the mathematical model results agreed well with the experimental data in references. The predicted detachment capacity calculated by the new method was capable of predicting saturated, unsaturated, and thawed slope, but incapable of partially thawed soil. This study not only supports the analytical solution to the differential equation of rill erosion, but also verifies that the experimental method was fit well with the mathematical concept. The new method provides a useful and efficient way to quantify rill erosion processes.
Summary
Background
Autophagy and genetic predisposition have been suggested to potentially play roles in the development of asthma. However, little is known about the role of autophagy in the ...pathogenesis of severe asthma.
Objective
We compared autophagy in the sputum granulocytes, peripheral blood cells (PBCs) and peripheral blood eosinophils (PBEs) between patients with severe asthma and those with non‐severe asthma and investigated the functional effects of autophagy.
Methods
We enrolled 36 patients with severe asthma, 14 with non‐severe asthma and 23 normal healthy controls in this study. Sputum granulocytes, PBCs and PBEs were isolated from each subject. Autophagy was evaluated based on the expression of microtubule‐associated protein light chain 3 (LC3) by Western blot, confocal microscopy, transmission electron microscopy and flow cytometry. IL‐8 levels were measured by ELISA. To induce autophagy, HL‐60 cells, human primary small airway epithelial cells (SAECs) and A549 cells were treated with IL‐5, IL‐1β and TNF‐α. To inhibit autophagy, PI3K inhibitors (LY29400 and 3‐methyladenine 3‐MA) and hydroxychloroquine (HCQ) were used. Knockdown of ATG5 and Beclin‐1 was performed in A549 cells, and the therapeutic effects of dexamethasone were evaluated.
Results
Higher autophagy levels were noted in sputum granulocytes, PBCs and PBEs from patients with severe asthma than from patients with non‐severe asthma and healthy controls (P < 0.05 for all). IL‐5 increased autophagy levels in both PBCs and PBEs (P < 0.05). 3‐MA attenuated the increased expression of LC3‐II and eosinophil cationic protein in HL‐60 cells induced by IL‐5 (P = 0.034 for both). Dexamethasone did not affect autophagy levels in PBEs. IL‐1β increased LC3‐II expression and IL‐8 production (P < 0.01) in SAECs, and this was attenuated by LY294002, 3‐MA, HCQ and knockdown of ATG5 and Beclin‐1 (in A549 cells) (P < 0.01).
Conclusions and Clinical Relevance
Autophagy could play a role in the pathogenesis of severe asthma. Autophagy modulation may be a novel therapeutic target for conventional therapy‐resistant severe asthma.
Background
Surfactant protein D (SPD) is a member of the collectin family that lines the airway epithelial cells with host defense. However, the role of SPD in the pathogenesis of aspirin‐exacerbated ...respiratory disease (AERD) is still unclear.
Methods
The serum SPD level was measured in patients with AERD (n = 336), those with aspirin‐tolerant asthma (ATA, n = 442), and healthy controls (HC, n = 104). Polymorphisms of SFTPD in the study subjects were analyzed. The effect of LTE4 on SPD production through eosinophil infiltration was investigated in BALB/c mice. The protective function of SPD against eosinophils inducing inflammation and remodeling was assessed in vitro/vivo. The potential efficacy of nintedanib against airway remodeling through the production of SPD was evaluated.
Results
The serum SPD level was significantly lower (P < .001) in AERD compared with ATA patients, and negatively correlated with fall in FEV1 (%) after lysine‐aspirin bronchoprovocation test and/or the urinary LTE4 level. In addition, polymorphism of SFTPD at rs721917 was significantly different in the study subjects (odds ratio, 2.124; 95% confidence intervals, 1.310‐3.446; P = .002). LTE4‐exposed mice showed an increased eosinophil count with a decreased SPD level in bronchoalveolar lavage fluid. Eosinophils increased α‐smooth muscle actin expression in airway epithelial cells, which was attenuated by SPD treatment. Furthermore, nintedanib protected the airway epithelial cells against eosinophils by enhancing the production of SPD.
Conclusion
The decreased level of SPD in AERD was associated with airway inflammation/remodeling under the eosinophilic condition, suggesting that modulation of SPD may provide a potential benefit in AERD.
High level of leukotriene E4 induces eosinophil infiltration in the lungs, leading to the reduction of surfactant protein D in patients with AERD. Decreased level of surfactant protein D and increased number of eosinophils enhance airway inflammation/remodeling. Modulation of surfactant protein D may provide a potential benefit in airway epithelium against eosinophils.
The use of an automated external defibrillator (AED) prior to EMS arrival can increase 30-day survival in out-of-hospital cardiac arrest (OHCA) significantly. Drones or unmanned aerial vehicles (UAV) ...can fly with high velocity and potentially transport devices such as AEDs to the site of OHCAs. The aim of this explorative study was to investigate the feasibility of a drone system in decreasing response time and delivering an AED.
Data of Global Positioning System (GPS) coordinates from historical OHCA in Stockholm County was used in a model using a Geographic Information System (GIS) to find suitable placements and visualize response times for the use of an AED equipped drone. Two different geographical models, urban and rural, were calculated using a multi-criteria evaluation (MCE) model. Test-flights with an AED were performed on these locations in rural areas.
In total, based on 3,165 retrospective OHCAs in Stockholm County between 2006-2013, twenty locations were identified for the potential placement of a drone. In a GIS-simulated model of urban OHCA, the drone arrived before EMS in 32 % of cases, and the mean amount of time saved was 1.5 min. In rural OHCA the drone arrived before EMS in 93 % of cases with a mean amount of time saved of 19 min. In these rural locations during (n = 13) test flights, latch-release of the AED from low altitude (3-4 m) or landing the drone on flat ground were the safest ways to deliver an AED to the bystander and were superior to parachute release.
The difference in response time for EMS between urban and rural areas is substantial, as is the possible amount of time saved using this UAV-system. However, yet another technical device needs to fit into the chain of survival. We know nothing of how productive or even counterproductive this system might be in clinical reality.
To use drones in rural areas to deliver an AED in OHCA may be safe and feasible. Suitable placement of drone systems can be designed by using GIS models. The use of an AED equipped drone may have the potential to reduce time to defibrillation in OHCA.
Summary
Background
A multidrug regimen including isoniazid, rifampicin, pyrazinamide and ethambutol is commonly used as first‐line treatment for tuberculosis. However, this regimen can occasionally ...result in severe adverse drug reactions, such as drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome and drug‐induced liver injury. The culprit drug and mechanistic basis for the hypersensitive reaction are unknown.
Objectives
To investigate drug‐specific T‐cell responses in patients with antituberculosis drug (ATD)‐induced cutaneous hypersensitivity and its underlying mechanism.
Methods
We enrolled eight patients with ATD‐induced maculopapular exanthema and DRESS and performed a lymphocyte transformation test. Subsequently, drug‐specific T‐cell clones were generated from four of the patients who showed proliferation in response to ATDs. We measured the drug‐specific proliferative responses and counted the drug‐specific interferon (IFN)‐γ/granzyme B‐producing cells after drug stimulation. Antihuman leukocyte antigen (HLA) class I and class II blocking antibodies were used to analyse human leukocyte antigen‐restricted T‐cell responses.
Results
Positive proliferative responses to ATDs were mostly found in patients with cutaneous hypersensitivity. Furthermore, we isolated isoniazid/rifampicin‐specific T cells from patients, which consisted primarily of CD4+ T cells. Drug‐specific CD4+ T cells proliferated and secreted IFN‐γ/granzyme B when stimulated with isoniazid or rifampicin, respectively. Isoniazid‐responsive T‐cell clones did not proliferate in the presence of rifampicin and vice versa. Drug‐specific T‐cell responses were blocked in the presence of anti‐HLA class II antibodies.
Conclusions
This study identifies the presence of isoniazid/rifampicin‐specific T cells in patients with ATD‐induced maculopapular exanthema and DRESS. Furthermore, it highlights the important role of drug‐specific T‐cell immune responses in the pathogenesis of these reactions.
What's already known about this topic?
Antituberculosis drug (ATD) treatment often induces severe adverse drug reactions including hepatotoxicity, drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome and maculopapular exanthema.
What does this study add?
This study identified an isoniazid/rifampicin‐specific T‐cell response in patients with ATD‐induced maculopapular exanthema and DRESS.
This study describes the nature of isoniazid/rifampicin‐specific CD4+ T cells and the mechanism of drug‐specific T‐cell activation in ATD‐induced maculopapular exanthema and DRESS syndrome.
What is the translational message?
As the first‐line treatment for tuberculosis is a combination regimen, the culprit drug is frequently not identified.
A lymphocyte transformation test for ATDs would be beneficial to assess the risk of drug hypersensitivity reaction.
Linked Comment: Pavlos et al. Br J Dermatol 2017; 176:292–293.
Summary
Background
To date, there has been no reliable in vitro test to diagnose aspirin‐exacerbated respiratory disease (AERD).
Objective
To investigate potential diagnostic biomarkers for AERD ...using metabolomic analysis.
Methods
An untargeted profile of serum from asthmatics in the first cohort (group 1) comprising 45 AERD, 44 patients with aspirin‐tolerant asthma (ATA), and 28 normal controls was developed using the ultra‐high‐performance liquid chromatography (UHPLC)/Q‐ToF MS system. Metabolites that discriminate AERD from ATA were quantified in both serum and urine, which were collected before (baseline) and after the lysine‐aspirin bronchoprovocation test (Lys‐ASA BPT). The serum metabolites were validated in the second cohort (group 2) comprising 50 patients with AERD and 50 patients with ATA.
Results
A clear discrimination of metabolomes was found between patients with AERD and ATA. In group 1, serum levels of LTE4 and LTE4/PGF2α ratio before and after the Lys‐ASA BPT were significantly higher in patients with AERD than in patients with ATA (P < 0.05 for each), and urine baseline levels of these two metabolites were significantly higher in patients with AERD. Significant differences of serum metabolite levels between patients with AERD and ATA were replicated in group 2 (P < 0.05 for each). Moreover, serum baseline levels of LTE4 and LTE4/PGF2α ratio discriminated AERD from ATA with 70.5%/71.6% sensitivity and 41.5%/62.8% specificity, respectively (AUC = 0.649 and 0.732, respectively P < 0.001 for each). Urine baseline LTE4 levels were significantly correlated with the fall in FEV1% after the Lys‐ASA BPT in patients with AERD (P = 0.008, r = 0.463).
Conclusions and Clinical Relevance
Serum metabolite level of LTE4 and LTE4/PGF2α ratio was identified as potential in vitro diagnostic biomarkers for AERD using the UHPLC/Q‐ToF MS system, which were closely associated with major pathogenetic mechanisms underlying AERD.
Red coloration of apple (Malus x domestica) skin is an important determinant of consumer preference and marketability. Anthocyanins are responsible for this coloration, and their accumulation is ...positively correlated with the expression level of anthocyanin biosynthetic genes. Regulation of expression of these genes is believed to be controlled by MYB transcription factors, and the MYB transcription factors involved in the activation of anthocyanin biosynthetic genes have been isolated in various plants. In the present study, we isolated and characterized a MYB transcription factor gene (MdMYBA) from apple skin. Characterization of MdMYBA demonstrated that (i) MdMYBA expression was specifically regulated depending on the tissue and cultivar/species; (ii) its expression level was much higher in a deep-red cultivar ('Jonathan') than in a pale-red cultivar ('Tsugaru'); (iii) when cauliflower mosaic virus 35S::MdMYBA was introduced into the cotyledons of apple seedlings by means of a transient assay, reddish-purple spots were induced, and MdMYBA also induced anthocyanin accumulation in reproductive tissues of transgenic tobacco; (iv) the expression of MdMYBA was induced by UV-B irradiation and low-temperature treatment, both of which are known to be important in the promotion of anthocyanin accumulation in apple skin; (v) MdMYBA bound specifically to an anthocyanidin synthase (MdANS) promoter region in a gel-shift assay; and (vi) MdMYBA was mapped to the near region of the BC226-STS (asup(1)) marker for the red skin color locus (Rsub(f)). These results suggest that MdMYBA is a key regulatory gene in anthocyanin biosynthesis in apple skin.
I have learned a great deal by participating in the ICRP dialogue seminars. I will summarise what I have observed and felt regarding the thoughts of the inhabitants of Fukushima over the last four ...and a half years, and what the ICRP dialogue seminars meant to them.
Quantum sensors leverage matter's quantum properties to enable measurements with unprecedented spatial and spectral resolution. Among these sensors, those utilizing nitrogen-vacancy (NV) centers in ...diamond offer the distinct advantage of operating at room temperature. Nevertheless, signals received from NV centers are often complex, making interpretation challenging. This is especially relevant in low magnetic field scenarios, where standard approximations for modeling the system fail. Additionally, NV signals feature a prominent noise component. In this Letter, we present a signal-to-image deep learning model capable of automatically inferring the number of nuclear spins surrounding a NV sensor and the hyperfine couplings between the sensor and the nuclear spins. Our model is trained to operate effectively across various magnetic field scenarios, requires no prior knowledge of the involved nuclei, and is designed to handle noisy signals, leading to fast characterization of nuclear environments in real experimental conditions. With detailed numerical simulations, we test the performance of our model in scenarios involving varying numbers of nuclei, achieving an average error of less than 2 kHz in the estimated hyperfine constants.
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