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1.
Langmuir ; 39(19): 6780-6793, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37140431

RESUMEN

Aerogels are becoming a promising platform to fabricate photothermal materials for use in solar steam generation (SSG), which have remarkable application potential in solar desalination, due to their excellent thermal management, salt resistance, and considerable water evaporation rate. In this work, a novel photothermal material is fabricated by forming a suspension between sugarcane bagasse fibers (SBF) and poly(vinyl alcohol), tannic acid (TA), and Fe3+ solutions via hydrogen bonds of hydroxyl groups. After freeze drying, the fabricated SBF aerogel-based photothermal (SBFAP) material possesses a 3D interconnected porous microstructure, which could enhance water transportation ability, reduce thermal conductivity, and quickly dissolve salt crystals on the SBFAP surface. Thanks to the formation of micro/nanosized complexes between TA and Fe3+ ions on the SBFAP material, the SBFAP exhibits high light capture and water evaporation rate (2.28 kg m-2 h-1). In particular, due to strong hydrogen bonding and the SBF, the SBFAP material is reinforced, thereby exhibiting excellent structural stability in seawater. Moreover, the high salt tolerance of SBFAP favors its high desalination performance for at least 76 days of continuous evaporation under actual conditions. This research paves the way for the fabrication of natural cellulose fiber-based photothermal materials for application in solar desalination.

2.
J Allergy Clin Immunol ; 147(4): 1464-1477.e11, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32920093

RESUMEN

BACKGROUND: Autophagy plays an important role in causing inflammatory responses initiated by environmental pollutants and respiratory tract infection. OBJECTIVE: We sought to investigate the role of cockroach allergen-induced excessive activation of autophagy in allergic airway inflammation and its underlying molecular mechanisms. METHODS: Environmental allergen-induced autophagy was investigated in the primary human bronchial epithelial cells (HBECs) and lung tissues of asthmatic mouse model and patients. The role of autophagy in asthma development was examined by using autophagy inhibitor 3-methyladenine in an asthma mouse model. Furthermore, the involvements of reactive oxygen species (ROS) and oxidized Ca2+/calmodulin-dependent protein kinase II (ox-CaMKII) signaling in regulating autophagy during asthma were examined in allergen-treated HBECs and mouse model. RESULTS: Cockroach allergen activated autophagy in HBECs and in the lung tissues from asthmatic patients and mice. Autophagy inhibitor 3-methyladenine significantly attenuated airway hyperresponsiveness, TH2-associated lung inflammation, and ROS generation. Mechanistically, we demonstrated a pathological feedforward circuit between cockroach allergen-induced ROS and autophagy that is mediated through CaMKII oxidation. Furthermore, transgenic mice with ROS-resistant CaMKII MM-VVδ showed attenuation of TH2-associated lung inflammation and autophagy. Mitochondrial ox-CaMKII inhibition induced by adenovirus carrying mitochondrial-targeted inhibitor peptide CaMKIIN suppresses cockroach allergen-induced autophagy, mitochondrial dysfunction, mitophagy, and cytokine production in HBECs. Finally, mitochondrial CaMKII inhibition suppressed the expression of one of the key ubiquitin-binding autophagy receptors, optineurin, and its recruitment to fragmented mitochondria. Optineurin knockdown inhibited cockroach allergy-induced mitophagy. CONCLUSIONS: Our data suggest a previously uncovered axis of allergen-ROS-ox-CaMKII-mitophagy in the development of allergic airway inflammation and asthma.


Asunto(s)
Alérgenos/inmunología , Asma/inmunología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/inmunología , Cucarachas/inmunología , Células Epiteliales/inmunología , Mitofagia , Animales , Bronquios/citología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Células Cultivadas , Citocinas/inmunología , Femenino , Humanos , Pulmón/inmunología , Masculino , Ratones Endogámicos C57BL , Ratones Mutantes , Oxidación-Reducción , Especies Reactivas de Oxígeno/inmunología
3.
J Immunol ; 201(3): 916-929, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29967100

RESUMEN

Exposure to cockroach allergen is a strong risk factor for developing asthma. Asthma has been associated with allergen-induced airway epithelial damage and heightened oxidant stress. In this study, we investigated cockroach allergen-induced oxidative stress in airway epithelium and its underlying mechanisms. We found that cockroach extract (CRE) could induce reactive oxygen species (ROS) production, particularly mitochondrial-derived ROS, in human bronchial epithelial cells. We then used the RT2 Profiler PCR array and identified that cyclooxygenase-2 (COX-2) was the most significantly upregulated gene related to CRE-induced oxidative stress. miR-155, predicted to target COX-2, was increased in CRE-treated human bronchial epithelial cells, and was showed to regulate COX-2 expression. Moreover, miR-155 can bind COX-2, induce COX-2 reporter activity, and maintain mRNA stability. Furthermore, CRE-treated miR-155-/- mice showed reduced levels of ROS and COX-2 expression in lung tissues and PGE2 in bronchoalveolar lavage fluid compared with wild-type mice. These miR-155-/- mice also showed reduced lung inflammation and Th2/Th17 cytokines. In contrast, when miR-155-/- mice were transfected with adeno-associated virus carrying miR-155, the phenotypic changes in CRE-treated miR-155-/- mice were remarkably reversed, including ROS, COX-2 expression, lung inflammation, and Th2/Th17 cytokines. Importantly, plasma miR-155 levels were elevated in severe asthmatics when compared with nonasthmatics or mild-to-moderate asthmatics. These increased plasma miR-155 levels were also observed in asthmatics with cockroach allergy compared with those without cockroach allergy. Collectively, these findings suggest that COX-2 is a major gene related to cockroach allergen-induced oxidative stress and highlight a novel role of miR-155 in regulating the ROS-COX-2 axis in asthma.


Asunto(s)
Alérgenos/inmunología , Asma/inmunología , Cucarachas/inmunología , Ciclooxigenasa 2/inmunología , MicroARNs/inmunología , Estrés Oxidativo/inmunología , Animales , Bronquios/inmunología , Líquido del Lavado Bronquioalveolar/inmunología , Células Cultivadas , Citocinas/inmunología , Células Epiteliales/inmunología , Humanos , Pulmón/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neumonía/inmunología , Especies Reactivas de Oxígeno/inmunología , Mucosa Respiratoria/inmunología , Células Th17/inmunología , Células Th2/inmunología
4.
J Allergy Clin Immunol ; 143(4): 1560-1574.e6, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30194990

RESUMEN

BACKGROUND: Numbers of mesenchymal stem cells (MSCs) are increased in the airways after allergen challenge. Ras homolog family member A (RhoA)/Rho-associated protein kinase 1 (ROCK) signaling is critical in determining the lineage fate of MSCs in tissue repair/remodeling. OBJECTIVES: We sought to investigate the role of RhoA/ROCK signaling in lineage commitment of MSCs during allergen-induced airway remodeling and delineate the underlying mechanisms. METHODS: Active RhoA expression in lung tissues of asthmatic patients and its role in cockroach allergen-induced airway inflammation and remodeling were investigated. RhoA/ROCK signaling-mediated MSC lineage commitment was assessed in an asthma mouse model by using MSC lineage tracing mice (nestin-Cre; ROSA26-EYFP). The role of RhoA/ROCK in MSC lineage commitment was also examined by using MSCs expressing constitutively active RhoA (RhoA-L63) or dominant negative RhoA (RhoA-N19). Downstream RhoA-regulated genes were identified by using the Stem Cell Signaling Array. RESULTS: Lung tissues from asthmatic mice showed increased expression of active RhoA when compared with those from control mice. Inhibition of RhoA/ROCK signaling with fasudil, a RhoA/ROCK inhibitor, reversed established cockroach allergen-induced airway inflammation and remodeling, as assessed based on greater collagen deposition/fibrosis. Furthermore, fasudil inhibited MSC differentiation into fibroblasts/myofibroblasts but promoted MSC differentiation into epithelial cells in asthmatic nestin-Cre; ROSA26-EYFP mice. Consistently, expression of RhoA-L63 facilitated differentiation of MSCs into fibroblasts/myofibroblasts, whereas expression of RhoA-19 switched the differentiation toward epithelial cells. The gene array identified the Wnt signaling effector lymphoid enhancer-binding factor 1 (Lef1) as the most upregulated gene in RhoA-L63-transfected MSCs. Knockdown of Lef1 induced MSC differentiation away from fibroblasts/myofibroblasts but toward epithelial cells. CONCLUSIONS: These findings uncover a previously unrecognized role of RhoA/ROCK signaling in MSC-involved airway repair/remodeling in the setting of asthma.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/inmunología , Asma/metabolismo , Factor de Unión 1 al Potenciador Linfoide/metabolismo , Células Madre Mesenquimatosas/metabolismo , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Animales , Asma/inmunología , Asma/patología , Linaje de la Célula/inmunología , Factor de Unión 1 al Potenciador Linfoide/inmunología , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/patología , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/inmunología , Quinasas Asociadas a rho/inmunología , Proteína de Unión al GTP rhoA/inmunología
5.
Allergy ; 74(9): 1675-1690, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30982974

RESUMEN

BACKGROUND: Environmental pollutants, which coexist with allergens, have been associated with the exacerbation of asthma. However, the underlying molecular mechanisms remain elusive. We sought to determine whether benzo(a)pyrene (BaP) co-exposure with dermatophagoides group 1 allergen (Der f 1) can potentiate Der f 1-induced asthma and its underlying mechanisms. METHODS: The effect of BaP was investigated in Der f 1-induced mouse model of asthma, including airway hyper-responsiveness, allergic inflammation, and epithelial-derived cytokines. The impact of BaP on Der f 1-induced airway epithelial cell oxidative stress (ROS) and cytokine release was further analyzed. The role of aryl hydrocarbon receptor (AhR) signaling in BaP-promoted Der f 1-induced ROS, cytokine production, and allergic inflammation was also investigated. RESULTS: Compared with Der f 1, BaP co-exposure with Der f 1 led to airway hyper-responsiveness and increased lung inflammation in mouse model of asthma. Increased expression of TSLP, IL-33, and IL-25 was also found in the airways of these mice. Moreover, BaP co-exposure with Der f 1 activated AhR signaling with increased expression of AhR and CYP1A1 and promoted airway epithelial ROS generation and TSLP and IL-33, but not IL-25, expression. Interestingly, AhR antagonist CH223191 or cells with AhR knockdown abrogated the increased expression of ROS, TSLP, and IL-33. Furthermore, ROS inhibitor N-acetyl-L-cysteine (NAC) also suppressed BaP co-exposure-induced expression of epithelial TSLP, IL-33, and IL-25. Finally, AhR antagonist CH223191 and NAC inhibited BaP co-exposure with Der f 1-induced lung inflammation. CONCLUSIONS: Our findings suggest that BaP facilitates Der f 1-induced epithelial cytokine release through the AhR-ROS axis.


Asunto(s)
Antígenos Dermatofagoides/inmunología , Proteínas de Artrópodos/inmunología , Asma/etiología , Asma/metabolismo , Benzo(a)pireno/efectos adversos , Cisteína Endopeptidasas/inmunología , Citocinas/biosíntesis , Receptores de Hidrocarburo de Aril/metabolismo , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Alérgenos/inmunología , Animales , Modelos Animales de Enfermedad , Contaminantes Ambientales/efectos adversos , Células Epiteliales/metabolismo , Humanos , Ratones , Especies Reactivas de Oxígeno/metabolismo
6.
J Allergy Clin Immunol ; 141(2): 586-600.e6, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28689792

RESUMEN

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with mast cell-mediated inflammation and heightened oxidant stress. Kynurenine (KYN), an endogenous tryptophan metabolite, can promote allergen-induced mast cell activation through the aryl hydrocarbon receptor (AhR). OBJECTIVES: We sought to determine the role of the KYN/AhR axis and oxidant stress in mast cell activation and the development of CRSwNP. METHODS: We measured the expression of indoleamine 2,3-dioxygenase 1, tryptophan 2,3-dioxygenase, KYN, and oxidized calmodulin-dependent protein kinase II (ox-CaMKII) in nasal polyps and controls. KYN-potentiated ovalbumin (OVA)-induced ROS generation, cell activation, and ox-CaMKII expression were investigated in wild-type and AhR-deficient (AhR-/-) mast cells. The role of ox-CaMKII in mast cell activation was further investigated. RESULTS: Nasal polyps in CRSwNP showed an increased expression of indoleamine 2,3-dioxygenase 1, tryptophan2,3-dioxygenase, and KYN compared with controls. AhR was predominantly expressed in mast cells in nasal polyps. Activated mast cells and local IgE levels were substantially increased in eosinophilic polyps compared with noneosinophilic polyps and controls. Furthermore, KYN potentiated OVA-induced ROS generation, intracellular Ca2+ levels, cell activation, and expression of ox-CaMKII in wild-type, but not in AhR-/- mast cells. Compared with noneosinophilic polyps and controls, eosinophilic polyps showed increased expression of ox-CaMKII in mast cells. Mast cells from ROS-resistant CaMKII MMVVδ mice or pretreated with CaMKII inhibitor showed protection against KYN-promoted OVA-induced mast cell activation. CONCLUSIONS: These studies support a potentially critical but previously unidentified function of the KYN/AhR axis in regulating IgE-mediated mast cell activation through ROS and ox-CaMKII in CRSwNP.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Pólipos Nasales/inmunología , Receptores de Hidrocarburo de Aril/inmunología , Receptores de Glutamato/inmunología , Rinitis/inmunología , Sinusitis/inmunología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/inmunología , Enfermedad Crónica , Eosinófilos/inmunología , Eosinófilos/patología , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Mastocitos/inmunología , Mastocitos/patología , Ratones , Ratones Noqueados , Pólipos Nasales/genética , Pólipos Nasales/patología , Receptores de Hidrocarburo de Aril/genética , Receptores de Glutamato/genética , Rinitis/genética , Rinitis/patología , Transducción de Señal/genética , Transducción de Señal/inmunología , Sinusitis/genética , Sinusitis/patología
7.
J Allergy Clin Immunol ; 141(1): 350-364.e8, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28629744

RESUMEN

BACKGROUND: Mannose receptor (MRC1/CD206) has been suggested to mediate allergic sensitization and asthma to multiple glycoallergens, including cockroach allergens. OBJECTIVE: We sought to determine the existence of a protective mechanism through which MRC1 limits allergic inflammation through its intronic miR-511-3p. METHODS: We examined MRC1-mediated cockroach allergen uptake by lung macrophages and lung inflammation using C57BL/6 wild-type (WT) and Mrc1-/- mice. The role of miR-511-3p in macrophage polarization and cockroach allergen-induced lung inflammation in mice transfected with adeno-associated virus (AAV)-miR-511-3p (AAV-cytomegalovirus-miR-511-3p-enhanced green fluorescent protein) was analyzed. Gene profiling of macrophages with or without miR-511-3p overexpression was also performed. RESULTS: Mrc1-/- lung macrophages showed a significant reduction in cockroach allergen uptake compared with WT mice, and Mrc1-/- mice had an exacerbated lung inflammation with increased levels of cockroach allergen-specific IgE and TH2/TH17 cytokines in a cockroach allergen-induced mouse model compared with WT mice. Macrophages from Mrc1-/- mice showed significantly reduced levels of miR-511-3 and an M1 phenotype, whereas overexpression of miR-511-3p rendered macrophages to exhibit a M2 phenotype. Furthermore, mice transfected with AAV-miR-511-3p showed a significant reduction in cockroach allergen-induced inflammation. Profiling of macrophages with or without miR-511-3p overexpression identified 729 differentially expressed genes, wherein expression of prostaglandin D2 synthase (Ptgds) and its product PGD2 were significantly downregulated by miR-511-3p. Ptgds showed a robust binding to miR-511-3p, which might contribute to the protective effect of miR-511-3p. Plasma levels of miR-511-3p were significantly lower in human asthmatic patients compared with nonasthmatic subjects. CONCLUSION: These studies support a critical but previously unrecognized role of MRC1 and miR-511-3p in protection against allergen-induced lung inflammation.


Asunto(s)
Hipersensibilidad/etiología , Hipersensibilidad/metabolismo , Lectinas Tipo C/metabolismo , Activación de Macrófagos/genética , Activación de Macrófagos/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Lectinas de Unión a Manosa/metabolismo , MicroARNs/genética , Receptores de Superficie Celular/metabolismo , Alérgenos/inmunología , Animales , Asma/etiología , Asma/metabolismo , Asma/patología , Cucarachas/inmunología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Vectores Genéticos/genética , Hipersensibilidad/patología , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/metabolismo , Receptor de Manosa , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Noqueados , Modelos Biológicos , Neumonía/etiología , Neumonía/metabolismo , Neumonía/patología , Interferencia de ARN , Receptores de Superficie Celular/genética , Receptores Inmunológicos
8.
J Immunol ; 195(12): 5539-50, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26561548

RESUMEN

Exposure to cockroach allergen leads to allergic sensitization and increased risk of developing asthma. Aryl hydrocarbon receptor (AhR), a receptor for many common environmental contaminants, can sense not only environmental pollutants but also microbial insults. Mesenchymal stem cells (MSCs) are multipotent progenitor cells with the capacity to modulate immune responses. In this study, we investigated whether AhR can sense cockroach allergens and modulate allergen-induced lung inflammation through MSCs. We found that cockroach allergen-treated AhR-deficient (AhR(-/-)) mice showed exacerbation of lung inflammation when compared with wild-type (WT) mice. In contrast, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an AhR agonist, significantly suppressed allergen-induced mouse lung inflammation. MSCs were significantly reduced in cockroach allergen-challenged AhR(-/-) mice as compared with WT mice, but increased in cockroach allergen-challenged WT mice when treated with TCDD. Moreover, MSCs express AhR, and AhR signaling can be activated by cockroach allergen with increased expression of its downstream genes cyp1a1 and cyp1b1. Furthermore, we tracked the migration of i.v.-injected GFP(+) MSCs and found that cockroach allergen-challenged AhR(-/-) mice displayed less migration of MSCs to the lungs compared with WT. The AhR-mediated MSC migration was further verified by an in vitro Transwell migration assay. Epithelial conditioned medium prepared from cockroach extract-challenged epithelial cells significantly induced MSC migration, which was further enhanced by TCDD. The administration of MSCs significantly attenuated cockroach allergen-induced inflammation, which was abolished by TGF-ß1-neutralizing Ab. These results suggest that AhR plays an important role in protecting lungs from allergen-induced inflammation by modulating MSC recruitment and their immune-suppressive activity.


Asunto(s)
Asma/prevención & control , Cucarachas/inmunología , Células Epiteliales/inmunología , Hipersensibilidad/inmunología , Células Madre Mesenquimatosas/fisiología , Receptores de Hidrocarburo de Aril/administración & dosificación , Alérgenos/inmunología , Animales , Anticuerpos Bloqueadores/farmacología , Asma/etiología , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Citocromo P-450 CYP1A1 , Citocromo P-450 CYP1B1 , Células Epiteliales/efectos de los fármacos , Hipersensibilidad/complicaciones , Inmunización , Proteínas de Insectos/administración & dosificación , Ratones , Ratones Noqueados , Neumonía/tratamiento farmacológico , Dibenzodioxinas Policloradas/administración & dosificación , Dibenzodioxinas Policloradas/farmacología , Receptores de Hidrocarburo de Aril/agonistas , Receptores de Hidrocarburo de Aril/genética , Factor de Crecimiento Transformador beta/farmacología
10.
ACS Appl Mater Interfaces ; 16(22): 29421-29438, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38776481

RESUMEN

2D/2D step-scheme (S-scheme) piezo-photocatalysts for the production of fine chemicals, such as hydrogen peroxide (H2O2), have attracted significant attention of global scientists owing to the efficiency in utilizing surface piezoelectric effects from 2D materials to overcome rapid charge recombination in photocatalytic processes. In this research, we reported the fabrication of 2D S-doped VOx deposited on 2D g-C3N4 to produce H2O2 via the piezo-photocatalytic process with high production yields at 20.19 mmol g-1 h-1, which was 1.75 and 4.87 times higher than that from solely piezo-catalytic and photocatalytic H2O2 generation. The finding pointed out that adding sulfur (S) to VOx can help to improve the catalytic outcomes by modifying the electronic properties of pristine VOx. In addition, when coupled with g-C3N4, the presence of S limits the formation of graphene in the VOx/g-C3N4 composites, causing shielding effects and pushing the cascade reactions toward water generation in the materials. Besides, the research also sheds light on the charge transport between g-C3N4 and S-VOx under irradiation and how the composites work to trigger the formation of H2O2. The presence of S in the composite systems enhances charge transfer between two semiconductors by strengthening the internal electric fields (IEF) to drive electrons moving in one direction, as demonstrated by density functional theory (DFT) calculations. Moreover, the formation of H2O2 significantly relies on the reduction of oxygen to generate oxygenic radical species at the g-C3N4 sites. Meanwhile, S-VOx provides oxidative sites in the composites to oxidize water molecules to directly or indirectly generate H2O2 or O2, which will further participate in the reactions to produce the final products. This study confirms the validation of S-scheme piezo-photocatalysts, thus encouraging further research on developing heterojunction materials with high catalytic efficiency, which can be used in practical conditions.

11.
Small Methods ; : e2400797, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39082067

RESUMEN

Hydrogen peroxide (H2O2) production via oxygen (O2) reduction reaction (ORR) in pure water (H2O) through graphitic carbon nitrides (g-C3N4)-based piezo-photocatalysts is an exciting approach in many current studies. However, the low Lewis-acid properties of g-C3N4 limited the catalytic performance because of the low O2 adsorption efficacy. To overcome this challenge, the interaction of g-C3N4 precursors with various solvents are utilized to synthesize g-C3N4, possessing multiple nitrogen-vacant species via thermal shocking polymerization. These results suggest that the lack of nitrogen in g-C3N4 and the incident introduction of oxygen-functional groups enhance the Lewis acid-base interactions and polarize the g-C3N4 lattices, leading to the enormous enhancement. Furthermore, the catalytic mechanisms are thoroughly studied, with the formation of H2O2 proceeding via radical and water oxidation pathways, in which the roles of light and ultrasound are carefully investigated. Thus, these findings not only reinforce the potential view of metal-free photocatalysts, accelerating the understanding of g-C3N4 working principles to generate H2O2 based on the oxygen reduction and water oxidation reactions, but also propose a facile one-step way for fabricating highly efficient and scalable photocatalysts to produce H2O2 without using sacrificial agents, pushing the practical application of in situ solar H2O2 toward real-world scenarios.

12.
RSC Adv ; 13(11): 7372-7379, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36895775

RESUMEN

A novel facile combination of precipitation and plasma discharge reaction is successfully employed for one-step synthesis of an α-Fe2O3-Fe3O4 graphene nanocomposite (GFs). The co-existence and anchoring of hematite (α-Fe2O3) and magnetite (Fe3O4) nanoparticles onto a graphene sheet in the as synthesized GFs were verified by results of XRD, Raman, SEM, TEM, and XPS. HRTEM characterization was used for confirming the bonding between α-Fe2O3/Fe3O4 nanoparticles and the graphene sheet. Consequently, GFs shows superior photodegrading performance towards methylene blue (MB), compared to individual α-Fe2O3/Fe3O4 nanoparticles, as a result of band gap narrowing and the electron-hole pair recombination rate reducing. Moreover, GFs allows a good possibility of separating and recycling under an external-magnetic field, suggesting potential in visible-light-promoted photocatalytic applications.

13.
Wound Repair Regen ; 20(3): 353-66, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22564230

RESUMEN

Proper healing of cutaneous wounds progresses through a series of overlapping phases. Nonhealing wounds are defective in one or more of these processes and represent a major clinical problem. A critical issue in developing treatments for chronic wounds is the paucity of animal models to study the mechanisms underlying the defects in healing. Here we show that deletion of tumor necrosis factor superfamily member 14 (TNFSF14/LIGHT) leads to impaired wounds in mice that have the characteristics of nonchronic and chronic ulcers. These wounds show: (1) excessive production of cytokines, in particular three chemokines (KC/CXCL8, MCP-1/CCL2, IP-10/CXCL10), that may be key to the abnormal initiation and resolution of inflammation; (2) defective basement membranes, explaining blood vessel leakage and disruption of dermal/epidermal interactions; and (3) granulation tissue that contains high levels of Coll III, whereas Coll I is virtually absent and does not form fibrils. We also see major differences between nonchronic and chronic wounds, with the latter populated by bacterial films and producing eotaxin, a chemokine that attracts leukocytes that combat multicellular organisms (which biofilms can be considered to be). This new mouse model captures many defects observed in impaired and chronic human wounds and provides a vehicle to address their underlying cell and molecular mechanisms.


Asunto(s)
Quimiocina CCL2/metabolismo , Quimiocina CXCL10/metabolismo , Eliminación de Gen , Interleucina-8/metabolismo , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/genética , Infección de Heridas/genética , Animales , Biopelículas/crecimiento & desarrollo , Enfermedad Crónica , Modelos Animales de Enfermedad , Ratones , Úlcera Cutánea/genética , Úlcera Cutánea/microbiología , Úlcera Cutánea/patología , Infecciones Cutáneas Estafilocócicas/genética , Infecciones Cutáneas Estafilocócicas/microbiología , Infecciones Cutáneas Estafilocócicas/patología , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/metabolismo , Cicatrización de Heridas/genética , Infección de Heridas/microbiología , Infección de Heridas/patología
14.
J Aerosol Med Pulm Drug Deliv ; 35(6): 296-306, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36318785

RESUMEN

Background: As the COVID-19 pandemic has progressed, numerous variants of SARS-CoV-2 have arisen, with several displaying increased transmissibility. Methods: The present study compared dose-response relationships and disease presentation in nonhuman primates infected with aerosols containing an isolate of the Gamma variant of SARS-CoV-2 to the results of our previous study with the earlier WA-1 isolate of SARS-CoV-2. Results: Disease in Gamma-infected animals was mild, characterized by dose-dependent fever and oronasal shedding of virus. Differences were observed in shedding in the upper respiratory tract between Gamma- and WA-1-infected animals that have the potential to influence disease transmission. Specifically, the estimated median doses for shedding of viral RNA or infectious virus in nasal swabs were approximately 10-fold lower for the Gamma variant than the WA-1 isolate. Given that the median doses for fever were similar, this suggests that there is a greater difference between the median doses for viral shedding and fever for Gamma than for WA-1 and potentially an increased range of doses for Gamma over which asymptomatic shedding and disease transmission are possible. Conclusions: These results complement those of previous studies, which suggested that differences in exposure dose may help to explain the range of clinical disease presentations observed in individuals with COVID-19, highlighting the importance of public health measures designed to limit exposure dose, such as masking and social distancing. The dose-response data provided by this study are important to inform disease transmission and hazard modeling, as well as to inform dose selection in future studies examining the efficacy of therapeutics and vaccines in animal models of inhalational COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Humanos , Pandemias/prevención & control , Administración por Inhalación , Primates
15.
PLoS Pathog ; 5(12): e1000695, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20019801

RESUMEN

Arenaviruses are the causative pathogens of severe hemorrhagic fever and aseptic meningitis in humans, for which no licensed vaccines are currently available. Pathogen heterogeneity within the Arenaviridae family poses a significant challenge for vaccine development. The main hypothesis we tested in the present study was whether it is possible to design a universal vaccine strategy capable of inducing simultaneous HLA-restricted CD8+ T cell responses against 7 pathogenic arenaviruses (including the lymphocytic choriomeningitis, Lassa, Guanarito, Junin, Machupo, Sabia, and Whitewater Arroyo viruses), either through the identification of widely conserved epitopes, or by the identification of a collection of epitopes derived from multiple arenavirus species. By inoculating HLA transgenic mice with a panel of recombinant vaccinia viruses (rVACVs) expressing the different arenavirus proteins, we identified 10 HLA-A02 and 10 HLA-A03-restricted epitopes that are naturally processed in human antigen-presenting cells. For some of these epitopes we were able to demonstrate cross-reactive CD8+ T cell responses, further increasing the coverage afforded by the epitope set against each different arenavirus species. Importantly, we showed that immunization of HLA transgenic mice with an epitope cocktail generated simultaneous CD8+ T cell responses against all 7 arenaviruses, and protected mice against challenge with rVACVs expressing either Old or New World arenavirus glycoproteins. In conclusion, the set of identified epitopes allows broad, non-ethnically biased coverage of all 7 viral species targeted by our studies.


Asunto(s)
Infecciones por Arenaviridae/terapia , Arenaviridae/inmunología , Vacunas Virales/inmunología , Animales , Antígenos Virales/uso terapéutico , Infecciones por Arenaviridae/prevención & control , Linfocitos T CD8-positivos/inmunología , Reacciones Cruzadas/inmunología , Epítopos/uso terapéutico , Antígenos HLA-A/uso terapéutico , Fiebres Hemorrágicas Virales/prevención & control , Fiebres Hemorrágicas Virales/terapia , Humanos , Inmunización , Ratones , Ratones Transgénicos , Resultado del Tratamiento
16.
Appl Opt ; 50(23): 4664-70, 2011 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-21833145

RESUMEN

We demonstrate the fabrication of a three-dimensional (3D) polymer quadratic nonlinear (χ(2)) grating structure. By performing layer-by-layer direct laser writing (DLW) and spin-coating approaches, desired photobleached grating patterns were embedded in the guest-host dispersed-red-1/poly(methylmethacrylate) (DR1/PMMA) active layers of an active-passive alternative multilayer structure through photobleaching of DR1 molecules. Polyvinyl-alcohol and SU8 thin films were deposited between DR1/PMMA layers serving as a passive layer to separate DR1/PMMA active layers. After applying the corona electric field poling to the multilayer structure, nonbleached DR1 molecules in the active layers formed polar distribution, and a 3D χ(2) grating structure was obtained. The χ(2) grating structures at different DR1/PMMA nonlinear layers were mapped by laser scanning second harmonic (SH) microscopy, and no cross talk was observed between SH images obtained from neighboring nonlinear layers. The layer-by-layer DLW technique is favorable to fabricating hierarchical 3D polymer nonlinear structures for optoelectronic applications with flexible structural design.

17.
Appl Opt ; 50(4): 579-85, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21283250

RESUMEN

We demonstrate a promising method for fabrication of plastic microlens arrays (MLAs) with a controllable ellipticity and structure, by using the combination of multiple-exposure two-beam interference and plastic replication techniques. Multiple exposures of a two-beam interference pattern with a wavelength of 442 nm into a thick positive photoresist (AZ-4620) were used to form different two-dimensional periodic structures. Thanks to the developing effect of the positive photoresist, fabricated structures consisting of hemielliptical- or hemispherical-shaped concave holes were obtained. By controlling the rotation angle between different exposures, both the shape and structure of the holes varied. By adjusting the dosage ratio between different exposures, the shape of the holes was modified while the structure of the holes was unchanged. The photoresist concave microstructures were then transferred to plastic MLAs by employing replication and embossing techniques. The fabricated MLAs were characterized by a scanning electron microscope and atomic force microscope measurements. We show that the ellipticity of the microlenses can be well controlled from 0 (hemispherical) to 0.96 (hemielliptical) by changing the rotation angle or dosage ratio between the two exposures.

18.
Front Immunol ; 12: 643260, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33936062

RESUMEN

We have previously demonstrated that benzo(a)pyrene (BaP) co-exposure with dermatophagoides group 1 allergen (Der f 1) can potentiate Der f 1-induced airway inflammation. The underlying mechanism, however, remains undetermined. Here we investigated the molecular mechanisms underlying the potentiation of BaP exposure on Der f 1-induced airway inflammation in asthma. We found that BaP co-exposure potentiated Der f 1-induced TGFß1 secretion and signaling activation in human bronchial epithelial cells (HBECs) and the airways of asthma mouse model. Moreover, BaP exposure alone or co-exposure with Der f 1-induced aryl hydrocarbon receptor (AhR) activity was determined by using an AhR-dioxin-responsive element reporter plasmid. The BaP and Der f 1 co-exposure-induced TGFß1 expression and signaling activation were attenuated by either AhR antagonist CH223191 or AhR knockdown in HBECs. Furthermore, AhR knockdown led to the reduction of BaP and Der f 1 co-exposure-induced active RhoA. Inhibition of RhoA signaling with fasudil, a RhoA/ROCK inhibitor, suppressed BaP and Der f 1 co-exposure-induced TGFß1 expression and signaling activation. This was further confirmed in HBECs expressing constitutively active RhoA (RhoA-L63) or dominant-negative RhoA (RhoA-N19). Luciferase reporter assays showed prominently increased promoter activities for the AhR binding sites in the promoter region of RhoA. Inhibition of RhoA suppressed BaP and Der f 1 co-exposure-induced airway hyper-responsiveness, Th2-associated airway inflammation, and TGFß1 signaling activation in asthma. Our studies reveal a previously unidentified functional axis of AhR-RhoA in regulating TGFß1 expression and signaling activation, representing a potential therapeutic target for allergic asthma.


Asunto(s)
Antígenos Dermatofagoides/toxicidad , Proteínas de Artrópodos/toxicidad , Asma , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Benzo(a)pireno/toxicidad , Cisteína Endopeptidasas/toxicidad , Receptores de Hidrocarburo de Aril/inmunología , Transducción de Señal , Factor de Crecimiento Transformador beta1/inmunología , Proteína de Unión al GTP rhoA/inmunología , Animales , Asma/inducido químicamente , Asma/inmunología , Asma/patología , Femenino , Masculino , Ratones , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología
19.
JCI Insight ; 6(14)2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34101619

RESUMEN

The small GTPase RhoA and its downstream effectors are critical regulators in the pathophysiological processes of asthma. The underlying mechanism, however, remains undetermined. Here, we generated an asthma mouse model with RhoA-conditional KO mice (Sftpc-cre;RhoAfl/fl) in type II alveolar epithelial cells (AT2) and demonstrated that AT2 cell-specific deletion of RhoA leads to exacerbation of allergen-induced airway hyperresponsiveness and airway inflammation with elevated Th2 cytokines in bronchoalveolar lavage fluid (BALF). Notably, Sftpc-cre;RhoAfl/fl mice showed a significant reduction in Tgf-ß1 levels in BALF and lung tissues, and administration of recombinant Tgf-ß1 to the mice rescued Tgf-ß1 and alleviated the increased allergic airway inflammation observed in Sftpc-cre;RhoAfl/fl mice. Using RNA sequencing technology, we identified Slc26a4 (pendrin), a transmembrane anion exchange, as the most upregulated gene in RhoA-deficient AT2 cells. The upregulation of SLC26A4 was further confirmed in AT2 cells of asthmatic patients and mouse models and in human airway epithelial cells expressing dominant-negative RHOA (RHOA-N19). SLA26A4 was also elevated in serum from asthmatic patients and negatively associated with the percentage of forced expiratory volume in 1 second (FEV1%). Furthermore, SLC26A4 inhibition promoted epithelial TGF-ß1 release and attenuated allergic airway inflammation. Our study reveals a RhoA/SLC26A4 axis in AT2 cells that functions as a protective mechanism against allergic airway inflammation.


Asunto(s)
Células Epiteliales Alveolares/inmunología , Asma/inmunología , Transportadores de Sulfato/metabolismo , Proteína de Unión al GTP rhoA/deficiencia , Células Epiteliales Alveolares/metabolismo , Animales , Asma/tratamiento farmacológico , Asma/patología , Líquido del Lavado Bronquioalveolar/inmunología , Modelos Animales de Enfermedad , Humanos , Pulmón/citología , Pulmón/inmunología , Pulmón/patología , Ratones , Ovalbúmina/administración & dosificación , Ovalbúmina/inmunología , Proteínas Recombinantes/administración & dosificación , Brote de los Síntomas , Factor de Crecimiento Transformador beta1/administración & dosificación , Factor de Crecimiento Transformador beta1/análisis , Factor de Crecimiento Transformador beta1/metabolismo , Proteína de Unión al GTP rhoA/genética
20.
Nat Commun ; 12(1): 3175, 2021 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-34039988

RESUMEN

Antagonistic pleiotropy is a foundational theory that predicts aging-related diseases are the result of evolved genetic traits conferring advantages early in life. Here we examine CaMKII, a pluripotent signaling molecule that contributes to common aging-related diseases, and find that its activation by reactive oxygen species (ROS) was acquired more than half-a-billion years ago along the vertebrate stem lineage. Functional experiments using genetically engineered mice and flies reveal ancestral vertebrates were poised to benefit from the union of ROS and CaMKII, which conferred physiological advantage by allowing ROS to increase intracellular Ca2+ and activate transcriptional programs important for exercise and immunity. Enhanced sensitivity to the adverse effects of ROS in diseases and aging is thus a trade-off for positive traits that facilitated the early and continued evolutionary success of vertebrates.


Asunto(s)
Envejecimiento/fisiología , Evolución Biológica , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Vertebrados/fisiología , Animales , Animales Modificados Genéticamente , Sistemas CRISPR-Cas/genética , Señalización del Calcio/fisiología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Femenino , Edición Génica , Técnicas de Sustitución del Gen , Masculino , Ratones , Modelos Animales , Oxidación-Reducción , Filogenia , Aptitud Física/fisiología , Mutación Puntual
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