Humidity sensors are essential components in wearable electronics for monitoring of environmental condition and physical state. In this work, a unique humidity sensing layer composed of ...nitrogen‐doped reduced graphene oxide (nRGO) fiber on colorless polyimide film is proposed. Ultralong graphene oxide (GO) fibers are synthesized by solution assembly of large GO sheets assisted by lyotropic liquid crystal behavior. Chemical modification by nitrogen‐doping is carried out under thermal annealing in H2(4%)/N2(96%) ambient to obtain highly conductive nRGO fiber. Very small (≈2 nm) Pt nanoparticles are tightly anchored on the surface of the nRGO fiber as water dissociation catalysts by an optical sintering process. As a result, nRGO fiber can effectively detect wide humidity levels in the range of 6.1–66.4% relative humidity (RH). Furthermore, a 1.36‐fold higher sensitivity (4.51%) at 66.4% RH is achieved using a Pt functionalized nRGO fiber (i.e., Pt‐nRGO fiber) compared with the sensitivity (3.53% at 66.4% RH) of pure nRGO fiber. Real‐time and portable humidity sensing characteristics are successfully demonstrated toward exhaled breath using Pt‐nRGO fiber integrated on a portable sensing module. The Pt‐nRGO fiber with high sensitivity and wide range of humidity detection levels offers a new sensing platform for wearable humidity sensors.
Nitrogen‐doped graphene fiber functionalized by Pt nanoparticles (Pt‐nRGO fiber) is integrated on a flexible and transparent polyimide substrate for application in real‐time and on‐site monitoring of humidity. This work demonstrates the humidity sensing characteristic of Pt‐nRGO fiber, which further expands versatility of graphene‐based fiber in wearable sensing electronics.
Due to the urgent need of a therapeutic treatment for coronavirus (CoV) disease 2019 (COVID-19) patients, a number of FDA-approved/repurposed drugs have been suggested as antiviral candidates at ...clinics, without sufficient information. Furthermore, there have been extensive debates over antiviral candidates for their effectiveness and safety against severe acute respiratory syndrome CoV 2 (SARS-CoV-2), suggesting that rapid preclinical animal studies are required to identify potential antiviral candidates for human trials. To this end, the antiviral efficacies of lopinavir-ritonavir, hydroxychloroquine sulfate, and emtricitabine-tenofovir for SARS-CoV-2 infection were assessed in the ferret infection model. While the lopinavir-ritonavir-, hydroxychloroquine sulfate-, or emtricitabine-tenofovir-treated group exhibited lower overall clinical scores than the phosphate-buffered saline (PBS)-treated control group, the virus titers in nasal washes, stool specimens, and respiratory tissues were similar between all three antiviral-candidate-treated groups and the PBS-treated control group. Only the emtricitabine-tenofovir-treated group showed lower virus titers in nasal washes at 8 days postinfection (dpi) than the PBS-treated control group. To further explore the effect of immune suppression on viral infection and clinical outcome, ferrets were treated with azathioprine, an immunosuppressive drug. Compared to the PBS-treated control group, azathioprine-immunosuppressed ferrets exhibited a longer period of clinical illness, higher virus titers in nasal turbinate, delayed virus clearance, and significantly lower serum neutralization (SN) antibody titers. Taken together, all antiviral drugs tested marginally reduced the overall clinical scores of infected ferrets but did not significantly affect
virus titers. Despite the potential discrepancy of drug efficacies between animals and humans, these preclinical ferret data should be highly informative to future therapeutic treatment of COVID-19 patients.
The SARS-CoV-2 pandemic continues to spread worldwide, with rapidly increasing numbers of mortalities, placing increasing strain on health care systems. Despite serious public health concerns, no effective vaccines or therapeutics have been approved by regulatory agencies. In this study, we tested the FDA-approved drugs lopinavir-ritonavir, hydroxychloroquine sulfate, and emtricitabine-tenofovir against SARS-CoV-2 infection in a highly susceptible ferret infection model. While most of the drug treatments marginally reduced clinical symptoms, they did not reduce virus titers, with the exception of emtricitabine-tenofovir treatment, which led to diminished virus titers in nasal washes at 8 dpi. Further, the azathioprine-treated immunosuppressed ferrets showed delayed virus clearance and low SN titers, resulting in a prolonged infection. As several FDA-approved or repurposed drugs are being tested as antiviral candidates at clinics without sufficient information, rapid preclinical animal studies should proceed to identify therapeutic drug candidates with strong antiviral potential and high safety prior to a human efficacy trial.
Effects of Air Pollutants on Airway Diseases Lee, Yun-Gi; Lee, Pureun-Haneul; Choi, Seon-Muk ...
International journal of environmental research and public health,
09/2021, Letnik:
18, Številka:
18
Journal Article
Recenzirano
Odprti dostop
Air pollutants include toxic particles and gases emitted in large quantities from many different combustible materials. They also include particulate matter (PM) and ozone, and biological ...contaminants, such as viruses and bacteria, which can penetrate the human airway and reach the bloodstream, triggering airway inflammation, dysfunction, and fibrosis. Pollutants that accumulate in the lungs exacerbate symptoms of respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). Asthma, a heterogeneous disease with complex pathological mechanisms, is characterized by particular symptoms such as shortness of breath, a tight chest, coughing, and wheezing. Patients with COPD often experience exacerbations and worsening of symptoms, which may result in hospitalization and disease progression. PM varies in terms of composition, and can include solid and liquid particles of various sizes. PM concentrations are higher in urban areas. Ozone is one of the most toxic photochemical air pollutants. In general, air pollution decreases quality of life and life expectancy. It exacerbates acute and chronic respiratory symptoms in patients with chronic airway diseases, and increases the morbidity and risk of hospitalization associated with respiratory diseases. However, the mechanisms underlying these effects remain unclear. Therefore, we reviewed the impact of air pollutants on airway diseases such as asthma and COPD, focusing on their underlying mechanisms.
PtO2 nanocatalysts-loaded SnO2 multichannel nanofibers (PtO2-SnO2 MCNFs) were synthesized by single-spinneret electrospinning combined with apoferritin and two immiscible polymers, i.e., ...poly(vinylpyrrolidone) and polyacrylonitrile. The apoferritin, which can encapsulate nanoparticles within a small inner cavity (8 nm), was used as a catalyst loading template for an effective functionalization of the PtO2 catalysts. Taking advantage of the multichannel structure with a high porosity, effective activation of catalysts on both interior and exterior site of MCNFs was realized. As a result, under high humidity condition (95% RH), PtO2-SnO2 MCNFs exhibited a remarkably high acetone response (R air/R gas = 194.15) toward 5 ppm acetone gases, superior selectivity to acetone molecules among various interfering gas species, and excellent stability during 30 cycles of response and recovery toward 1 ppm acetone gases. In this work, we first demonstrate the high suitability of multichannel semiconducting metal oxides structure functionalized by apoferritin-encapsulated catalytic nanoparticles as highly sensitive and selective gas-sensing layer.
Background
Junctional adhesion molecule (JAM)‐A is an immunoglobulin‐like molecule that colocalizes with tight junctions (TJs) in endothelium and epithelium and is also found on blood leukocytes and ...platelets.
Objective
We aimed to elucidate the role of JAM‐A on airway hyperresponsiveness and inflammation in asthma using a murine asthma model, and to check blood level of JAM‐A in asthmatic patients.
Methods;
Using mice sensitized and challenged with OVA, as well as mice sensitized and challenged with saline, we investigated whether Jam‐a be involved in the pathogenesis of bronchial asthma. The level of JAM‐A was checked in the plasma of asthmatic patients and control subjects. The relation of JAM‐A with clinical variables in patients with asthma was searched.
Results
JAM‐A level had higher concentrations in plasma from patients with asthma (n = 19) than that of healthy controls (n = 12). JAM‐A level was correlated with FVC%, FEV1%, FEV1/FVC, total IgE, and blood lymphocyte proportion in patients with asthma. Jam‐a protein expression in lung tissue was significantly increased in OVA/OVA mice compared with control mice. Phospho‐JNK and phosphor‐ERK protein expression in lung tissue was significantly increased in OVA/OVA mice compared with control mice. A western blotting was used NHBE cells treated with HDM extracts for 4, 8 and 24 h. NHBE cells showed that HDM extracts resulted in increased JAM‐A, phospho‐JNK, phospho‐ERK expression.
Conclusion;
These data suggest that JAM‐A be elevated in plasma of patients with asthma, which raise the possibility that JAM‐A be involved in asthma through JNK and ERK pathway.
Protective masks impose variable breathing resistance (BR) on the wearer and may adversely affect exercise performance, yet existing literature shows inconsistent results under different types of ...masks and metabolic demands. The present study was undertaken to determine whether added BR impairs cardiopulmonary function and aerobic performance during exercise. Sixteen young healthy men completed a graded exercise test on a cycle ergometer under the four conditions of BR using a customized breathing resistor at no breathing resistance (CON), 18.9 (BR1), 22.2 (BR2), and 29.9 Pa (BR3). The results showed that BR significantly elevates respiratory pressure (
< 0.001) and impairs ventilatory response to graded exercise (reduced V
;
< 0.001) at a greater degree with an increased level of BR which caused mild to moderate exercise-induced hypoxemia (final mean SpO
: CON = 95.6%, BR1 = 94.4%, BR2 = 91.6%, and BR3 = 90.6%;
< 0.001). Especially, such a marked reduction in SpO
was significantly correlated with maximal oxygen consumption at the volitional fatigue (r = 0.98,
< 0.001) together with exaggerated exertion and breathing discomfort (
< 0.001). In conclusion, added BR commonly experienced when wearing tight-fitting facemasks and/or respirators could significantly impair cardiopulmonary function and aerobic performance at a greater degree with an increasing level of BR.
Bimodally meso- (2–50 nm) and macroporous (>50 nm) WO3 microbelts (MBs) functionalized with sub-3 nm Pt catalysts were fabricated via the electrospinning technique followed by subsequent calcination. ...Importantly, apoferritin (Apo), tea saponin and polystyrene colloid spheres (750 nm) dispersed in an electrospinning solution acted as forming agents for producing meso- and macropores on WO3 MBs during calcination. Particularly, mesopores provide not only numerous reaction sites for effective chemical reactions, but also facilitate gas diffusion into the interior of the WO3 MBs, dominated by Knudsen diffusion. The macropores further accelerate gas permeability in the interior and on the exterior of the WO3 MBs. In addition, Pt nanoparticles with mean diameters of 2.27 nm were synthesized by using biological protein cages, such as Apo, to further enhance the gas sensing performance. Bimodally porous WO3 MBs functionalized by Pt catalysts showed remarkably high hydrogen sulfide (H2S) response (R air/R gas = 61 @ 1 ppm) and superior selectivity to H2S against other interfering gases, such as acetone (CH3COCH3), ethanol (C2H5OH), ammonia (NH3), and carbon monoxide (CO). These results demonstrate a high potential for the feasibility of catalyst-loaded meso- and macroporous WO3 MBs as new sensing platforms for the possibility of real-time diagnosis of halitosis.
Remote ischemic preconditioning (RIPC) has been shown to minimize subsequent ischemia-reperfusion injury (IRI), whereas obesity has been suggested to attenuate the efficacy of RIPC in animal models. ...The primary objective of this study was to investigate the effect of a single bout of RIPC on the vascular and autonomic response after IRI in young obese men. A total of 16 healthy young men (8 obese and 8 normal weight) underwent two experimental trials: RIPC (three cycles of 5 min ischemia at 180 mmHg + 5 min reperfusion on the left thigh) and SHAM (the same RIPC cycles at resting diastolic pressure) following IRI (20 min ischemia at 180 mmHg + 20 min reperfusion on the right thigh). Heart rate variability (HRV), blood pressure (SBP/DBP), and cutaneous blood flow (CBF) were measured between baseline, post-RIPC/SHAM, and post-IRI. The results showed that RIPC significantly improved the LF/HF ratio (
0.027), SBP (
0.047), MAP (
0.049), CBF (
0.001), cutaneous vascular conductance (
0.003), vascular resistance (
0.001), and sympathetic reactivity (SBP:
0.039; MAP:
0.084) after IRI. However, obesity neither exaggerated the degree of IRI nor attenuated the conditioning effects on the measured outcomes. In conclusion, a single bout of RIPC is an effective means of suppressing subsequent IRI and obesity, at least in Asian young adult men, does not significantly attenuate the efficacy of RIPC.
•AuCl3-doped graphene was used as transparent electrode for perovskite solar cells.•The Fermi level of graphene was controllable by doping concentration of AuCl3.•Highly efficient CH3NH3PbI3 ...perovskite solar cells (17.4–17.9% at 1 Sun) were fabricated.
We employed AuCl3-doped graphene as a p-type transparent conducting electrode (TCE) in an p-i-n type CH3NH3PbI3 perovskite solar cell using poly (3,4-ethylenedioxythiophene):poly(styrene sulfonate) and phenyl-C61-butyric acid methyl ester as the hole and electron transporting layers, respectively, and obtained 17.4–17.9% power conversion efficiency at 1 Sun condition. The work function of the AuCl3-doped graphene TCE was controllable from ∼4.52 to ∼4.86eV. Due to the p-type doping by the AuCl3 treatment, the graphene TCE shows good hole mobility and greatly-improved sheet resistance (∼70ohm/cm2) compared to the pristine graphene TCE (∼890ohm/cm2) but its transmittance was gradually decreased with the doping concentration (nD). Owing to the trade-off correlation between the sheet resistance and the transmittance of the AuCl3-doped graphene TCE, the ratio of DC conductivity and optical conductivity was the highest at nD=7.5mM. Therefore, the highest performance was achievable by using 7.5mM AuCl3-doped graphene TCE.
Respiratory epithelial cells form a selective barrier between the outside environment and underlying tissues. Epithelial cells are polarized and form specialized cell-cell junctions, known as the ...apical junctional complex (AJC). Assembly and disassembly of the AJC regulates epithelial morphogenesis and remodeling processes. The AJC consists of tight and adherens junctions, functions as a barrier and boundary, and plays a role in signal transduction. Endothelial junction proteins play important roles in tissue integrity and vascular permeability, leukocyte extravasation, and angiogenesis. Air pollutants such as particulate matter, ozone, and biologic contaminants penetrate deep into the airways, reaching the bronchioles and alveoli before entering the bloodstream to trigger airway inflammation. Pollutants accumulating in the lungs exacerbate the symptoms of respiratory diseases, including asthma and chronic obstructive lung disease. Biological contaminants include bacteria, viruses, animal dander and cat saliva, house dust mites, cockroaches, and pollen. Allergic inflammation develops in tissues such as the lung and skin with large epithelial surface areas exposed to the environment. Barrier dysfunction in the lung allows allergens and environmental pollutants to activate the epithelium and produce cytokines that promote the induction and development of immune responses. In this article, we review the impact of environmental pollutants on the cell barrier in respiratory diseases.
PDF
