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1.
Immunity ; 56(2): 320-335.e9, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36693372

RESUMEN

Neuronal signals have emerged as pivotal regulators of group 2 innate lymphoid cells (ILC2s) that regulate tissue homeostasis and allergic inflammation. The molecular pathways underlying the neuronal regulation of ILC2 responses in lungs remain to be fully elucidated. Here, we found that the abundance of neurotransmitter dopamine was negatively correlated with circulating ILC2 numbers and positively associated with pulmonary function in humans. Dopamine potently suppressed lung ILC2 responses in a DRD1-receptor-dependent manner. Genetic deletion of Drd1 or local ablation of dopaminergic neurons augmented ILC2 responses and allergic lung inflammation. Transcriptome and metabolic analyses revealed that dopamine impaired the mitochondrial oxidative phosphorylation (OXPHOS) pathway in ILC2s. Augmentation of OXPHOS activity with oltipraz antagonized the inhibitory effect of dopamine. Local administration of dopamine alleviated allergen-induced ILC2 responses and airway inflammation. These findings demonstrate that dopamine represents an inhibitory regulator of ILC2 responses in allergic airway inflammation.


Asunto(s)
Inmunidad Innata , Neumonía , Humanos , Dopamina/metabolismo , Linfocitos , Pulmón/metabolismo , Neumonía/metabolismo , Inflamación/metabolismo , Interleucina-33/metabolismo
3.
Immunology ; 172(2): 226-234, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38409805

RESUMEN

Group 2 innate lymphoid cells (ILC2s) play critical roles in driving the pathogenesis of allergic airway inflammation. The mechanisms underlying the regulation of ILC2s remain to be fully understood. Here, we identified neuropilin-1 (NRP1) as a surface marker of ILC2s in response to IL-33 stimulation. NRP1 was abundantly expressed in ILC2s from lung under steady state, which was significantly reduced upon IL-33 stimulation. ILC2s with high expression of NRP1 (NRP1high) displayed lower response to IL-33, as compared with NRP1low ILC2s. Transcriptional profiling and flow cytometric analysis showed that downregulation of AKT-mTOR signalling participated in the diminished functionality of NRP1high ILC2s. These observations revealed a potential role of NRP1 in ILC2s responses under allergic inflammatory condition.


Asunto(s)
Regulación hacia Abajo , Inmunidad Innata , Interleucina-33 , Linfocitos , Neuropilina-1 , Transducción de Señal , Interleucina-33/metabolismo , Interleucina-33/inmunología , Animales , Neuropilina-1/metabolismo , Neuropilina-1/genética , Ratones , Linfocitos/inmunología , Linfocitos/metabolismo , Pulmón/inmunología , Pulmón/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones Endogámicos C57BL
4.
Small ; 20(12): e2307565, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37946670

RESUMEN

Liquid crystal elastomers (LCEs) with promising applications in the field of actuators and soft robotics are reported. However, most of them are activated by external heating or light illumination. The examples of electroactive LCEs are still limited; moreover, they are monofunctional with one type of deformation (bending or contraction). Here, the study reports on trilayer electroactive LCE (eLCE) by intimate combination of LCE and ionic electroactive polymer device (i-EAD). This eLCE is bi-functional and can perform either bending or contractile deformations by the control of the low-voltage stimulation. By applying a voltage of ±2 V at 0.1 Hz, the redox behavior and associated ionic motion provide a bending strain difference of 0.80%. Besides, by applying a voltage of ±6 V at 10 Hz, the ionic current-induced Joule heating triggers the muscle-like linear contraction with 20% strain for eLCE without load. With load, eLCE can lift a weight of 270 times of eLCE-actuator weight, while keeping 20% strain and affording 5.38 kJ·m-3 work capacity. This approach of combining two smart polymer technologies (LCE and i-EAD) in a single device is promising for the development of smart materials with multiple degrees of freedom in soft robotics, electronic devices, and sensors.

5.
Nano Lett ; 23(5): 1954-1960, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36790322

RESUMEN

Highly efficient perovskite optoelectronics (POEs) have been limited by nonradiative recombination. We report a strategy to inhibit the nonradiative recombination of 2D triphenylamine polymers in the hole transport layer (HTL) via introducing electron-donating groups to enhance the conjugation effect and electron cloud density. The conjugated systems with electron-donating groups present smaller energy level oscillation compared to the ones with electron-absorbing groups, as confirmed by nonadiabatic molecular dynamics (NAMD) calculation. Further study reveals that the introduction of low-frequency phonons in the electron-donating group systems shortens the nonadiabatic coupling and inhibits the nonradiative recombination. Such electron-donating groups can decrease the valence band maximum of 2D polymers and promote hole transport. Our report provides a new design strategy to suppress nonradiative recombination in HTL for application in efficient POEs.

6.
Phys Chem Chem Phys ; 25(13): 9123-9130, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36938685

RESUMEN

In order to accelerate the application of quaternary optoelectronic materials in the field of luminescence, it is crucial to develop new quaternary semiconductor materials with excellent properties. However, faced with vast alternative quaternary semiconductors, traditional trial-and-error methods tend to be laborious and inefficient. Here, we combined machine learning (ML) with density functional theory (DFT) calculation to predict the bandgaps of 2180 quaternary semiconductors, most of which were undeveloped but environmentally friendly. The evaluation coefficient (R2) of the model using a random forest algorithm was up to 0.93 in ML. Four novel quaternary semiconductors with direct bandgaps: Ag2InGaS4, AgZn2InS4, Ag2ZnSnS4, and AgZn2GaS4, were selected from the ML model. Then their electronic structures and optical properties were further verified and studied by DFT calculations, which demonstrated that the four quaternary semiconductors had direct bandgaps, a small effective mass, and a large exciton binding energy and Stokes shift. Our calculation could significantly speed up the discovery of novel optoelectronic semiconductors and has a certain reference value for the study of luminescent materials and devices.

7.
Nanotechnology ; 33(34)2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35584638

RESUMEN

All-inorganic lead-free perovskite CsSnBr3, has been proved good stability and optoelectronic properties in theory and experiment. However, the interfacial electronic properties of metal/CsSnBr3are still unclear in electronic devices. Herein, we systematically investigate the interfacial properties of metal electrodes (Al, Ag and Au) and CsSnBr3with different atomic terminals (SnBr2-T and CsBr-T) through the first-principles calculation. SnBr2-T and CsBr-T have various contact types and Schottky barriers due to their different interaction strengths with metals. In particular, the moderate interlayer coupling strength with Al leads to the ultra-low Schottky barrier and tunneling barrier, which makes Al possess the best contact performance among the studied metals. Furthermore, the external electric field can be effective in regulating the Schottky barrier and realizing the Ohmic contact. These findings provide useful guidance for the design of perovskite-based nanoelectronic devices with high performance.

8.
J Immunol ; 205(1): 36-44, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32444391

RESUMEN

Group 2 innate lymphoid cells (ILC2s) play an important role in the control of tissue inflammation and homeostasis. However, the role of ILC2s in patients with end-stage renal disease (ESRD) has never been illustrated. In this study, we investigated ILC2s in ESRD patients and their clinical significance. Results showed that the frequencies and absolute numbers of ILC2s, not group 1 innate lymphoid cells or innate lymphoid cell precursors, were significantly elevated in the peripheral blood of ESRD patients when compared with those from healthy donor controls. Moreover, ILC2s from ESRD patients displayed enhanced type 2 cytokine production and cell proliferation. Plasma from ESRD patients significantly increased ILC2 levels and enhanced their effector function after in vitro treatment. The expression of phosphorylation of STAT5 in ILC2s, as well as the amounts of IL-2 in plasma, were increased in ESRD patients when compared with those from healthy donors. Clinically, ESRD patients with higher ILC2 frequencies displayed lower incidence of infectious complications during a mean of 21 month follow-up study. The proportions of ILC2s were negatively correlated with the prognostic biomarkers of chronic kidney disease, including serum parathyroid hormone, creatinine, and phosphorus, whereas they were positively correlated with serum calcium. These observations indicate that ILC2s may play a protective role in ESRD.


Asunto(s)
Inmunidad Innata , Fallo Renal Crónico/inmunología , Subgrupos Linfocitarios/inmunología , Adulto , Animales , Biomarcadores/sangre , Estudios de Casos y Controles , Proliferación Celular , Células Cultivadas , Citocinas/metabolismo , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Voluntarios Sanos , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/terapia , Recuento de Linfocitos , Subgrupos Linfocitarios/metabolismo , Masculino , Persona de Mediana Edad , Cultivo Primario de Células , Pronóstico , Diálisis Renal/estadística & datos numéricos
9.
Front Immunol ; 15: 1367230, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919617

RESUMEN

The transitory emergence of myeloid-derived suppressor cells (MDSCs) in infants is important for the homeostasis of the immune system in early life. The composition and functional heterogeneity of MDSCs in newborns remain elusive, hampering the understanding of the importance of MDSCs in neonates. In this study, we unraveled the maturation trajectory of polymorphonuclear (PMN)-MDSCs from the peripheral blood of human newborns by performing single-cell RNA sequencing. Results indicated that neonatal PMN-MDSCs differentiated from self-renewal progenitors, antimicrobial PMN-MDSCs, and immunosuppressive PMN-MDSCs to late PMN-MDSCs with reduced antimicrobial capacity. We also established a simple framework to distinguish these distinct stages by CD177 and CXCR2. Importantly, preterm newborns displayed a reduced abundance of classical PMN-MDSCs but increased late PMN-MDSCs, consistent with their higher susceptibility to infections and inflammation. Furthermore, newborn PMN-MDSCs were distinct from those from cancer patients, which displayed minimum expression of genes about antimicrobial capacity. This study indicates that the heterogeneity of PMN-MDSCs is associated with the maturity of human newborns.


Asunto(s)
Perfilación de la Expresión Génica , Células Supresoras de Origen Mieloide , Receptores de Interleucina-8B , Análisis de la Célula Individual , Transcriptoma , Humanos , Células Supresoras de Origen Mieloide/inmunología , Células Supresoras de Origen Mieloide/metabolismo , Recién Nacido , Receptores de Interleucina-8B/metabolismo , Receptores de Interleucina-8B/genética , Neutrófilos/inmunología , Neutrófilos/metabolismo , Proteínas Ligadas a GPI/genética , Diferenciación Celular , Femenino , Masculino , Isoantígenos , Receptores de Superficie Celular
10.
J Cell Biol ; 223(3)2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38349334

RESUMEN

The cell cycle is a highly regulated process in which proteins involved in cell cycle progression exhibit periodic expression patterns, controlled by specific mechanisms such as transcription, translation, and degradation. However, the precise mechanisms underlying the oscillations of mRNA levels in cell cycle regulators are not fully understood. In this study, we observed that the stability of cyclin D1 (CCND1) mRNA fluctuates during the cell cycle, with increased stability during interphase and decreased stability during the M phase. Additionally, we identified a key RNA binding protein, positive coactivator 4 (PC4), which plays a crucial role in stabilizing CCND1 mRNA and regulating its periodic expression. Moreover, the binding affinity of PC4 to CCND1 mRNA is modulated by two cell cycle-specific posttranslational modifications: ubiquitination of K68 enhances binding and stabilizes the CCND1 transcript during interphase, while phosphorylation of S17 inhibits binding during the M phase, leading to degradation of CCND1 mRNA. Remarkably, PC4 promotes the transition from G1 to S phase in the cell cycle, and depletion of PC4 enhances the efficacy of CDK4/6 inhibitors in hepatocellular carcinoma, suggesting that PC4 could serve as a potential therapeutic target. These findings provide valuable insights into the intricate regulation of cell cycle dynamics.


Asunto(s)
Ciclo Celular , Ciclina D1 , Estabilidad del ARN , Proteínas de Unión al ARN , Ciclo Celular/genética , División Celular , Ciclina D1/genética , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina , Estabilidad del ARN/genética , ARN Mensajero/genética , Masculino , Animales , Ratones , Ratones Endogámicos BALB C , Humanos , Línea Celular Tumoral , Proteínas de Unión al ARN/genética , Fosforilación , Ubiquitinación
11.
Pathol Res Pract ; 259: 155369, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38820928

RESUMEN

Bladder cancer is a common malignancy with a poor prognosis worldwide. Positive cofactor 4 (PC4) is widely reported to promote malignant phenotypes in various tumors. Nonetheless, the biological function and mechanism of PC4 in bladder cancer remain unclear. Here, for the first time, we report that PC4 is elevated in bladder cancer and is associated with patient survival. Moreover, PC4 deficiency obviously inhibited bladder cancer cell proliferation and metastasis by reducing the expression of genes related to cancer stemness (CD44, CD47, KLF4 and c-Myc). Through RNA-seq and experimental verification, we found that activation of the Wnt5a/ß-catenin pathway is involved in the malignant function of PC4. Mechanistically, PC4 directly interacts with Sp1 to promote Wnt5a transcription. Thus, our study furthers our understanding of the role of PC4 in cancer stemness regulation and provides a promising strategy for bladder cancer therapy.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Factor 4 Similar a Kruppel , Células Madre Neoplásicas , Neoplasias de la Vejiga Urinaria , Proteína Wnt-5a , Animales , Humanos , Ratones , beta Catenina/metabolismo , beta Catenina/genética , Línea Celular Tumoral , Proliferación Celular/genética , Progresión de la Enfermedad , Factor 4 Similar a Kruppel/metabolismo , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/metabolismo , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp1/genética , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/metabolismo , Vía de Señalización Wnt/fisiología , Vía de Señalización Wnt/genética , Proteína Wnt-5a/metabolismo , Proteína Wnt-5a/genética
12.
ACS Appl Mater Interfaces ; 15(43): 50254-50264, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37847863

RESUMEN

I-III-VI quantum dots (QDs) and derivatives (I, III, and VI are Ag+/Cu+, Ga3+/In3+, and S2-/Se2-, respectively) are the ideal candidates to replace II-VI (e.g., CdSe) and perovskite QDs due to their nontoxicity, pure color, high photoluminescence quantum yield (PLQY), and full visible coverage. However, the chaotic cation alignment in multielement systems can easily lead to the formation of multiple surface vacancies, highlighted as VI and VVI, leading to nonradiative recombination and nonequilibrium carrier distribution, which severely limit the performance improvement of materials and devices. Here, based on Zn-Ag-In-Ga-S QDs, we construct an ultrathin indium sulfide shell that can passivate electron vacancies and convert donor/acceptor level concentrations. The optimized In-rich 2-layer indium sulfide structure not only enhances the radiative recombination rate by preventing further VS formation but also achieves the typical DAP emission enhancement, achieving a significant increase in PLQY to 86.2% at 628 nm. Moreover, the optimized structure can mitigate the lattice distortion and make the carrier distribution in the interior of the QDs more balanced. On this basis, red QD light-emitting diodes (QLEDs) with the highest external quantum efficiency (EQE; 5.32%) to date were obtained, providing a novel scheme for improving I-III-VI QD-based QLED efficiency.

13.
Front Psychol ; 14: 1170669, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37560098

RESUMEN

Introduction: Though the important effect of cultural identity on subjective well-being is widely acknowledged, the details of how different cultures' unique features influence well-being remain to be revealed. To address this issue in the context of Chinese culture, the present study investigates whether and how the prominent features of Chinese culture-collectivism and red culture-shape Chinese people's subjective well-being. Methods: The Red Cultural Identity Scale, Subjective Well-Being Scale, Collectivism Scale, and Perspective-Taking Scale were used to assess 1,045 Chinese residents. Results: The results showed that red cultural identity positively predicted participants' subjective well-being through the mediated role of collectivism. Furthermore, perspective-taking was found to moderate the mediating effect of collectivism. Discussion: These results demonstrate that the way cultural identity predicts subjective well-being is highly correlated to specific cultural features, e.g., the opinion of values, which was significant in practice with a cross-cultural background.

14.
Adv Mater ; 35(35): e2301914, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37171937

RESUMEN

Thermochromic fluorescent materials (TFMs) characterized by noticeable emission color variation with temperature have attracted pervasive attention for their frontier application in stimulus-response and optical encryption technologies. However, existing TFMs typically suffer from weak PL reversibility as well as limited mild operating temperature and severe temperature PL quenching. PL switching under extreme conditions such as high temperature will undoubtedly improve encryption security, while it is still challenging for present TFMs. In this work, high-temperature thermochromic fluorescence up to 473 K and robust structural and optical reversibility of 80 cycles are observed in Rb2 MnBr4 (H2 O)2 and related crystals, which is seldom reported for PL changes at such a high temperature. Temperature-driven nonluminous, red and green light emission states can be achieved at specific temperatures and the modulation mechanism is verified by in situ optical and structural measurements and single particle transition. By virtue of this unique feature, a multicolor anti-counterfeiting label based on a broad temperature gradient and multidimensional information encryption applications are demonstrated. This work opens a window for the design of inorganic materials with multi-PL change and the development of advanced encryption strategies with extreme stimuli source.

15.
Dose Response ; 20(1): 15593258221081317, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35221823

RESUMEN

During a major radiation event, a large number of people need to be rapidly assessed for radiation damage to ensure effective medical treatment and efficient use of medical resources. However, current techniques cannot meet the requirement of rapid detection of large quantities of samples in an emergency. It is essential to develop rapid and accurate radiation biodosimeters in peripheral blood. Here, we identified radiation sensitive genes in mice by RNA sequencing and evaluated their utility as radiation biodosimeters in human cell lines. Mice were subjected to gamma-irradiation with different doses (0-8 Gy, .85 Gy/min), and the tail venous blood was analyzed by RNA sequencing. We have identified 5 genes with significantly differential expression after radiation exposure. We found that positive cofactor 4(PC4) had well correlation with radiation dose in human lymphoblastoid cell line after irradiation. The relative expression of PC4 gene showed a good linear correlation with the radiation dose after 1-5 Gy irradiation (.85 Gy/min). PC4 gene can be rapidly recruited to the DNA damage sites faster than γ-H2AX after radiation in immunofluorescence detection. In conclusion, PC4 may be represented as new radiation biological dosimeter for early assessment.

16.
Mucosal Immunol ; 15(2): 314-326, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34686839

RESUMEN

Group 2 innate lymphoid cells (ILC2s) play an important role in allergic airway inflammation. Despite recent advances in defining molecular mechanisms that control ILC2 development and function, the role of endogenous metabolites in the regulation of ILC2s remains poorly understood. Herein, we demonstrated that bilirubin, an end product of heme catabolism, was a potent negative regulator of ILC2s. Bilirubin metabolism was found to be significantly induced during airway inflammation in mouse models. The administration of unconjugated bilirubin (UCB) dramatically suppressed ILC2 responses to interleukin (IL)-33 in mice, including cell proliferation and the production of effector cytokines. Furthermore, UCB significantly alleviated ILC2-driven airway inflammation, which was aggravated upon clearance of endogenous UCB. Mechanistic studies showed that the effects of bilirubin on ILC2s were associated with downregulation of ERK phosphorylation and GATA3 expression. Clinically, newborns with hyperbilirubinemia displayed significantly lower levels of ILC2 with impaired function and suppressed ERK signaling. Together, these findings indicate that bilirubin serves as an endogenous suppressor of ILC2s and might have potential therapeutic value in the treatment of allergic airway inflammation.


Asunto(s)
Bilirrubina , Linfocitos , Hipersensibilidad Respiratoria , Animales , Bilirrubina/farmacología , Citocinas/metabolismo , Inmunidad Innata , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Interleucina-33/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Linfocitos/patología , Ratones , Hipersensibilidad Respiratoria/inmunología , Hipersensibilidad Respiratoria/metabolismo , Sistema Respiratorio/inmunología , Sistema Respiratorio/metabolismo
17.
Mucosal Immunol ; 15(2): 338-350, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34921233

RESUMEN

Although group 2 Innate Lymphoid Cells (ILC2s) play important roles in driving the pathogenesis of allergic airway inflammation, the molecular mechanisms regulating ILC2 responses remain to be fully elucidated. Adenosine signaling is emerging as an important factor to limit excessive inflammation and tissue damage, its role in ILC2-driven airway inflammation remains to be understood. Here we identify adenosine as a negative regulator of ILC2s and allergic airway inflammation. Elevation of adenosine was observed in lungs after protease papain challenge. Adenosine receptor A2A was abundantly expressed in lung ILC2s. The adenosine analog NECA significantly suppress ILC2s responses and relieved airway inflammation induced by IL-33 or papain. Conversely, blockage of adenosine synthesis by CD73 inhibitor APCP or deficiency of A2A aggravated murine airway inflammation. Adoptive transfer of ILC2s into immunodeficiency NCG mice demonstrated that the regulation of ILC2 by adenosine was cell intrinsic. Mechanistic studies showed that the effects of adenosine on ILC2s were associated with changes in transcriptional profiling, and the elevation of intracellular cAMP and resulted NF-κB downregulation. These observations indicate that adenosine-A2A signaling is a negative regulator of ILC2s, which confers protection against airway inflammation and represents a novel therapeutic target for controlling asthma.


Asunto(s)
Adenosina , Hipersensibilidad , Inmunidad Innata , Linfocitos , Receptor de Adenosina A2A , Adenosina/metabolismo , Animales , Hipersensibilidad/inmunología , Inflamación/inmunología , Interleucina-33/inmunología , Pulmón/inmunología , Linfocitos/inmunología , Ratones , Receptor de Adenosina A2A/inmunología
18.
J Exp Med ; 219(3)2022 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-35044462

RESUMEN

Group 2 innate lymphoid cells (ILC2s) have emerged as critical mediators in driving allergic airway inflammation. Here, we identified angiotensin (Ang) II as a positive regulator of ILC2s. ILC2s expressed higher levels of the Ang II receptor AT1a, and colocalized with lung epithelial cells expressing angiotensinogen. Administration of Ang II significantly enhanced ILC2 responses both in vivo and in vitro, which were almost completely abrogated in AT1a-deficient mice. Deletion of AT1a or pharmacological inhibition of the Ang II-AT1 axis resulted in a remarkable remission of airway inflammation. The regulation of ILC2s by Ang II was cell intrinsic and dependent on interleukin (IL)-33, and was associated with marked changes in transcriptional profiling and up-regulation of ERK1/2 phosphorylation. Furthermore, higher levels of plasma Ang II correlated positively with the abundance of circulating ILC2s as well as disease severity in asthmatic patients. These observations reveal a critical role for Ang II in regulating ILC2 responses and airway inflammation.


Asunto(s)
Angiotensina II/metabolismo , Inmunidad Innata , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/metabolismo , Receptor de Angiotensina Tipo 1/metabolismo , Enfermedades Respiratorias/etiología , Enfermedades Respiratorias/metabolismo , Animales , Biomarcadores , Hiperreactividad Bronquial/etiología , Hiperreactividad Bronquial/metabolismo , Hiperreactividad Bronquial/patología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Inflamación , Interleucina-33/metabolismo , Ratones , Ratones Noqueados , Receptor de Angiotensina Tipo 1/genética , Enfermedades Respiratorias/patología
19.
ACS Appl Mater Interfaces ; 13(45): 54439-54446, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34738782

RESUMEN

Stimuli-responsive liquid crystal elastomers (LCEs), which exhibit sophisticated and versatile shape variations and functions upon stimulations, have constantly interested material science researchers. To date, many challenges still exist in scaling up orientated LCEs with sophisticated physical shapes and multi-functions. Herein, LCEs with various customizable conventional and exotic three-dimensional (3D) shapes and with sizes larger than those previously reported have been prepared by combining magnetic field alignment and soft lithography technology. These LCEs have film, cylinder, ellipsoid, hemispheroid, tube, pyramid, triangle and rectangle frame, grid pattern, cubic frame, and spring shapes. Meanwhile, diversified deformation behaviors such as contraction, expansion, bending, and twisting have been achieved by effectively controlling the alignment directions. Finally, the LCE actuator with hemispheroid shape has been explored for its possible applications in dynamic Braille displays or lenses with adjustable focal length. The simple strategy reported here provides a convenient way to customize multimorphological large-size 3D LCE actuators and their stimuli-responsive deformations. These systems will considerably enlarge the potential applications of LCEs and benefit the development of LCE soft robots and the future special bionic systems.

20.
IEEE Trans Neural Syst Rehabil Eng ; 28(6): 1334-1343, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32286999

RESUMEN

Active transtibial prostheses, orthoses, and exoskeletons hold the promise of improving the mobility of lower-limb impaired or amputated individuals. Locomotion mode identification (LMI) is essential for these devices precisely reproducing the required function in different terrains. In this study, a terrain geometry-based LMI algorithm is proposed. The environment should be built according to the inclination grade of the ground. For example, when the inclination angle is between 7 degrees and 15 degrees, the environment should be a ramp. If the inclination angle is around 30 degrees, the environment is preferred to be equipped with stairs. Given that, the locomotion mode/terrain can be classified by the inclination grade. Besides, human feet always move along the surface of terrain to minimize the energy expenditure for transporting lower limbs and get the required foot clearance. Hence, the foot trajectory estimated by an IMU was used to derive the inclination grade of the terrain that we traverse to identify the locomotion mode. In addition, a novel trigger condition (an elliptical boundary) is proposed to activate the decision-making of the LMI algorithm before the next foot strike thus leaving enough time for performing preparatory work in the swing phase. When the estimated foot trajectory goes across the elliptical boundary, the decision-making will be executed. Experimental results show that the average accuracy for three healthy subjects and three below-knee amputees is 98.5% in five locomotion modes: level-ground walking, up slope, down slope, stair descent, and stair ascent. Besides, all the locomotion modes can be identified before the next foot strike.


Asunto(s)
Amputados , Miembros Artificiales , Dispositivo Exoesqueleto , Fenómenos Biomecánicos , Marcha , Humanos , Locomoción , Aparatos Ortopédicos , Caminata
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