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1.
Chem Rev ; 124(4): 1464-1534, 2024 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-38314694

RESUMEN

Haptic human-machine interfaces (HHMIs) combine tactile sensation and haptic feedback to allow humans to interact closely with machines and robots, providing immersive experiences and convenient lifestyles. Significant progress has been made in developing wearable sensors that accurately detect physical and electrophysiological stimuli with improved softness, functionality, reliability, and selectivity. In addition, soft actuating systems have been developed to provide high-quality haptic feedback by precisely controlling force, displacement, frequency, and spatial resolution. In this Review, we discuss the latest technological advances of soft sensors and actuators for the demonstration of wearable HHMIs. We particularly focus on highlighting material and structural approaches that enable desired sensing and feedback properties necessary for effective wearable HHMIs. Furthermore, promising practical applications of current HHMI technology in various areas such as the metaverse, robotics, and user-interactive devices are discussed in detail. Finally, this Review further concludes by discussing the outlook for next-generation HHMI technology.


Asunto(s)
Dispositivos Electrónicos Vestibles , Humanos , Reproducibilidad de los Resultados
2.
Soft Robot ; 11(2): 270-281, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38112297

RESUMEN

A human can intuitively perceive and comprehend complicated tactile information because the cutaneous receptors distributed in the fingertip skin receive different tactile stimuli simultaneously and the tactile signals are immediately transmitted to the brain. Although many research groups have attempted to mimic the structure and function of human skin, it remains a challenge to implement human-like tactile perception process inside one system. In this study, we developed a real-time and multimodal tactile system that mimics the function of cutaneous receptors and the transduction of tactile stimuli from receptors to the brain, by using multiple sensors, a signal processing and transmission circuit module, and a signal analysis module. The proposed system is capable of simultaneously acquiring four types of decoupled tactile information with a compact system, thereby enabling differentiation between various tactile stimuli, texture characteristics, and consecutive complex motions. This skin-like three-dimensional integrated design provides further opportunities in multimodal tactile sensing systems.


Asunto(s)
Piel , Percepción del Tacto , Humanos , Tacto/fisiología , Dedos , Encéfalo
3.
Gland Surg ; 12(7): 905-916, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37727334

RESUMEN

Background: SurgiGuard® is an absorbent hemostatic agent based on oxidized regenerated cellulose. The efficacy, effects and safety of SurgiGuard® are equivalent to existing hemostatic agents in animal experiments. This study was designed to confirm that the use of SurgiGuard® alone is effective, safe and feasible compared to combination with other hemostatic methods. Methods: We retrospectively reviewed clinical data from 12 surgery departments in seven tertiary centers in South Korea nationwide. All surgeries were performed between January and December 2018. Results: A total of 807 patients were enrolled; 447 patients (55.4%) had comorbidities. The rate of major surgery (operative time ≥4 hours) was 44% (n=355 patients). Regarding the type of SurgiGuard® used in surgery, more than 70% of minor surgeries used non-woven types. In major surgery, more than five SurgiGuards® were used in 7.3% (26 patients), and the proportion of co-usage (with four other hemostatic products) was 19.7% (70 patients). The effectiveness score was higher when SurgiGuard® was used alone in both major (5.3±0.5 vs. 5.1±0.6, P=0.048) and minor surgery (5.4±0.6 vs. 5.2±0.4, P<0.001). Seven patients had immediate re-bleeding, and all of them used SurgiGuard® and other products together. Nine patients reported adverse effects, such as abscess, bleeding, or leg swelling, but we found no direct correlation with SurgiGuard®. Conclusions: SurgiGuard® exhibited greater effectiveness when used alone. No direct adverse effects associated with SurgiGuard® use were reported, and SurgiGuard® had stable feasibility. Prospective comparative studies are needed in the future.

4.
Adv Mater ; 35(46): e2306637, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37740254

RESUMEN

Film-type shape-configurable speakers with tunable sound directivity are in high demand for wearable electronics. Flexible, thin thermoacoustic (TA) loudspeakers-which are free from bulky vibrating diaphragms-show promise in this regard. However, configuring thin TA loudspeakers into arbitrary shapes is challenging because of their low sound pressure level (SPL) under mechanical deformations and low conformability to other surfaces. By carefully controlling the heat capacity per unit area and thermal effusivity of an MXene conductor and substrates, respectively, it fabricates an ultrathin MXene-based TA loudspeaker exhibiting high SPL output (74.5 dB at 15 kHz) and stable sound performance for 14 days. Loudspeakers with the parylene substrate, whose thickness is less than the thermal penetration depth, generated bidirectional and deformation-independent sound in bent, twisted, cylindrical, and stretched-kirigami configurations. Furthermore, it constructs parabolic and spherical versions of ultrathin, large-area (20 cm × 20 cm) MXene-based TA loudspeakers, which display sound-focusing and 3D omnidirectional-sound-generating attributes, respectively.

5.
Hear Res ; 433: 108770, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37104990

RESUMEN

Selective auditory attention has been shown to modulate the cortical representation of speech. This effect has been well documented in acoustically more challenging environments. However, the influence of top-down factors, in particular topic familiarity, on this process remains unclear, despite evidence that semantic information can promote speech-in-noise perception. Apart from individual features forming a static listening condition, dynamic and irregular changes of auditory scenes-volatile listening environments-have been less studied. To address these gaps, we explored the influence of topic familiarity and volatile listening on the selective auditory attention process during dichotic listening using electroencephalography. When stories with unfamiliar topics were presented, participants' comprehension was severely degraded. However, their cortical activity selectively tracked the speech of the target story well. This implies that topic familiarity hardly influences the speech tracking neural index, possibly when the bottom-up information is sufficient. However, when the listening environment was volatile and the listeners had to re-engage in new speech whenever auditory scenes altered, the neural correlates of the attended speech were degraded. In particular, the cortical response to the attended speech and the spatial asymmetry of the response to the left and right attention were significantly attenuated around 100-200 ms after the speech onset. These findings suggest that volatile listening environments could adversely affect the modulation effect of selective attention, possibly by hampering proper attention due to increased perceptual load.


Asunto(s)
Percepción Auditiva , Percepción del Habla , Humanos , Percepción del Habla/fisiología , Audición , Electroencefalografía , Atención/fisiología
6.
Sci Adv ; 8(12): eabj9220, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35333568

RESUMEN

Accurate transmission of biosignals without interference of surrounding noises is a key factor for the realization of human-machine interfaces (HMIs). We propose frequency-selective acoustic and haptic sensors for dual-mode HMIs based on triboelectric sensors with hierarchical macrodome/micropore/nanoparticle structure of ferroelectric composites. Our sensor shows a high sensitivity and linearity under a wide range of dynamic pressures and resonance frequency, which enables high acoustic frequency selectivity in a wide frequency range (145 to 9000 Hz), thus rendering noise-independent voice recognition possible. Our frequency-selective multichannel acoustic sensor array combined with an artificial neural network demonstrates over 95% accurate voice recognition for different frequency noises ranging from 100 to 8000 Hz. We demonstrate that our dual-mode sensor with linear response and frequency selectivity over a wide range of dynamic pressures facilitates the differentiation of surface texture and control of an avatar robot using both acoustic and mechanical inputs without interference from surrounding noise.

7.
ACS Nano ; 16(1): 1208-1219, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35020369

RESUMEN

When we touch an object, thermosensation allows us to perceive not only the temperature but also wetness and types of materials with different thermophysical properties (i.e., thermal conductivity and heat capacity) of objects. Emulation of such sensory abilities is important in robots, wearables, and haptic interfaces, but it is challenging because they are not directly perceptible sensations but rather learned abilities via sensory experiences. Emulating the thermosensation of human skin, we introduce an artificial thermosensation based on an intelligent thermo-/calorimeter (TCM) that can objectively differentiate types of contact materials and solvents with different thermophysical properties. We demonstrate a TCM based on pyroresistive composites with ultrahigh sensitivity (11.2% °C-1) and high accuracy (<0.1 °C) by precisely controlling the melt-induced volume expansion of a semicrystalline polymer, as well as the negative temperature coefficient of reduced graphene oxide. In addition, the ultrathin TCM with coplanar electrode design shows deformation-insensitive temperature sensing, facilitating wearable skin temperature monitoring with accuracy higher than a commercial thermometer. Moreover, the TCM with a high pyroresistivity can objectively differentiate types of contact materials and solvents with different thermophysical properties. In a proof-of-principle application, our intelligent TCM, coupled with a machine-learning algorithm, enables objective evaluation of the thermal attributes (coolness and wetness) of skincare products.


Asunto(s)
Grafito , Humanos , Grafito/química , Solventes , Temperatura Cutánea , Tacto , Piel
8.
Adv Sci (Weinh) ; 9(9): e2105423, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35072354

RESUMEN

Multifunctional electronic skins have attracted considerable attention for soft electronics including humanoid robots, wearable devices, and health monitoring systems. Simultaneous detection of multiple stimuli in a single self-powered device is desired to simplify artificial somatosensory systems. Here, inspired by the structure and function of human skin, an ultrasensitive self-powered multimodal sensor is demonstrated based on an interlocked ferroelectric copolymer microstructure. The triboelectric and pyroelectric effects of ferroelectric microstructures enable the simultaneous detection of mechanical and thermal stimuli in a spacer-free single device, overcoming the drawbacks of conventional devices, including complex fabrication, structural complexity, and high-power consumption. Furthermore, the interlocked microstructure induces electric field localization during ferroelectric polarization, leading to enhanced output performance. The multimodal tactile sensor provides ultrasensitive pressure and temperature detection capability (2.2 V kPa-1 , 0.27 nA °C-1 ) over a broad range (0.1-98 kPa, -20 °C < ΔT < 30 °C). Furthermore, multiple simultaneous stimuli can be distinguished based on different response times of triboelectric and pyroelectric effects. The remarkable performance of this sensor enables real-time monitoring of pulse pressure, acoustic wave detection, surface texture analysis, and profiling of multiple stimuli.


Asunto(s)
Tacto , Dispositivos Electrónicos Vestibles , Electrónica , Humanos , Piel/química
9.
Adv Sci (Weinh) ; 8(13): 2005010, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34258158

RESUMEN

High-performance biodegradable electronic devices are being investigated to address the global electronic waste problem. In this work, a fully biodegradable ferroelectric nanogenerator-driven skin sensor with ultrasensitive bimodal sensing capability based on edible porcine skin gelatine is demonstrated. The microstructure and molecular engineering of gelatine induces polarization confinement that gives rise the ferroelectric properties, resulting in a piezoelectric coefficient (d33) of ≈24 pC N-1 and pyroelectric coefficient of ≈13 µC m-2K-1, which are 6 and 11.8 times higher, respectively, than those of the conventional planar gelatine. The ferroelectric gelatine skin sensor has exceptionally high pressure sensitivity (≈41 mV Pa-1) and the lowest detection limit of pressure (≈0.005 Pa) and temperature (≈0.04 K) ever reported for ferroelectric sensors. In proof-of-concept tests, this device is able to sense the spatially resolved pressure, temperature, and surface texture of an unknown object, demonstrating potential for robotic skins and wearable electronics with zero waste footprint.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Diseño de Equipo/métodos , Gelatina/química , Piel/química , Dispositivos Electrónicos Vestibles , Animales , Biodegradación Ambiental , Porcinos
10.
ACS Nano ; 15(1): 1795-1804, 2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33369402

RESUMEN

Hierarchical and gradient structures in biological systems with special mechanical properties have inspired innovations in materials design for construction and mechanical applications. Analogous to the control of stress transfer in gradient mechanical structures, the control of electron transfer in gradient electrical structures should enable the development of high-performance electronics. This paper demonstrates a high performance electronic skin (e-skin) via the simultaneous control of tactile stress transfer to an active sensing area and the corresponding electrical current through the gradient structures. The flexible e-skin sensor has extraordinarily high piezoresistive sensitivity at low power and linearity over a broad pressure range based on the conductivity-gradient multilayer on the stiffness-gradient interlocked microdome geometry. While stiffness-gradient interlocked microdome structures allow the efficient transfer and localization of applied stress to the sensing area, the multilayered structure with gradient conductivity enables the efficient regulation of piezoresistance in response to applied pressure by gradual activation of current pathways from outer to inner layers, resulting in a pressure sensitivity of 3.8 × 105 kPa-1 with linear response over a wide range of up to 100 kPa. In addition, the sensor indicated a rapid response time of 0.016 ms, a low minimum detectable pressure level of 0.025 Pa, a low operating voltage (100 µV), and high durability during 8000 repetitive cycles of pressure application (80 kPa). The high performance of the e-skin sensor enables acoustic wave detection, differentiation of gas characterized by different densities, subtle tactile manipulation of objects, and real-time monitoring of pulse pressure waveform.

11.
Global Spine J ; 11(5): 662-668, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32875896

RESUMEN

STUDY DESIGN.: Retrospective study. OBJECTIVE.: Cervical pedicle screw (CPS) placement is technically demanding because of the great variation in pedicle size, dimension, and angulations between cervical levels and patients and the lack of anatomical landmarks. This retrospective study was conducted to analyze novice neurosurgeons' experience of CPS placement by using the technique with direct exposure of pedicle via para-articular minilaminotomy. METHODS.: We retrospectively reviewed 78 CPSs in 22 consecutive patients performed by 2 surgeons. All pedicle screws were inserted under the direct visualization of the pedicle by using para-articular minilaminotomy without any fluoroscopic guidance. We analyzed the direction and grade of pedicle perforation on the postoperative computed tomography scan. The degree of perforation was classified as grade 0 to 3. Grades 0 and 1 were classified as the correct position and the others, as the incorrect position. RESULTS.: In total, the correct position (grade 0 and 1) was found in 72 (92.3%) screws and the incorrect position (grade 2 and 3) in 6 (7.7%). Among the 16 pedicle perforations (grade 1, 2, and 3 perforations), the directions were lateral in 15 (93.8%) and superior in 1 (6.2%). There were no neurovascular complications related to CPS insertion. CONCLUSION.: Free-hand CPS placement by using para-articular minilaminotomy seems to be feasible and reproducible.

12.
ACS Appl Mater Interfaces ; 12(52): 58403-58411, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33342213

RESUMEN

Flexible pressure sensors have been widely explored for their versatile applications in electronic skins, wearable healthcare monitoring devices, and robotics. However, fabrication of sensors with characteristics such as high sensitivity, linearity, and simple fabrication process remains a challenge. Therefore, we propose herein a highly flexible and sensitive pressure sensor based on a conductive binary spiky/spherical nanoparticle film that can be fabricated by a simple spray-coating method. The sea-urchin-shaped spiky nanoparticles are based on the core-shell structures of spherical silica nanoparticles decorated with conductive polyaniline spiky shells. The simple spray coating of binary spiky/spherical nanoparticles enables the formation of uniform conductive nanoparticle-based films with hierarchical nano/microstructures. The two differently shaped particles-based films (namely sea-urchin-shaped and spherical) when interlocked face-to-face to form a bilayer structure can be used as a highly sensitive piezoresistive pressure sensor. Our optimized pressure sensor exhibits high sensitivity (17.5 kPa-1) and linear responsivity over a wide pressure range (0.008-120 kPa), owing to the effects of stress concentration and gradual deformation of the hierarchical microporous structures with sharp nanoscale tips. Moreover, the sensor exhibits high durability over 6000 repeated cycles and practical applicability in wearable devices that can be used for healthcare monitoring and subtle airflow detection (1 L/min).

13.
Sci Rep ; 10(1): 11070, 2020 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-32632123

RESUMEN

We investigated the anti-angiogenic and pro-apoptotic effects of robustaflavone (RF), a naturally occurring biflavonoid, on human umbilical vein endothelial cells (HUVECs). RF inhibited HUVEC proliferation and showed cytotoxicity that inhibited HUVEC viability. RF-induced apoptosis was characterized by flow cytometry and caspase 3 analysis. We found that RF increased the number of sub-G1 cells and terminal deoxynucleotidyl transferase dUTP nick end-labeled cells. Additionally, RF induced caspase 3 and poly (ADP-ribose) polymerase activation. Potential molecular targets were identified using a human apoptosis antibody array. RF upregulated Bax, Bad, cleaved caspase 3, p21, and phosphorylated p53 levels. RF induced mitochondrial membrane potential loss and the release of cytochrome c and apoptosis-inducing factor. Cell cycle arrest at G0/G1 phase and the downregulation of Cdk4, Cdk6, and cyclin D1 expression were induced by RF. In vivo anti-angiogenic effects were investigated using a tumor allograft animal model and a Matrigel plug assay. RF reduced the volumes and weights of CT-26 cell-derived tumors. The blood vessel density was significantly decreased in RF-treated tumors. RF also inhibited VEGF-A-stimulated blood vessel formation in vivo in Matrigel plugs. These results suggest that RF can potentially inhibit angiogenesis-dependent tumor growth and metastasis.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Apoptosis/efectos de los fármacos , Biflavonoides/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Neoplasias del Colon/patología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Neovascularización Patológica/tratamiento farmacológico , Animales , Proliferación Celular , Neoplasias del Colon/irrigación sanguínea , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Femenino , Fase G1 , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fase de Descanso del Ciclo Celular , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Artículo en Inglés | MEDLINE | ID: mdl-32664696

RESUMEN

Although participating in regular physical activity has many benefits, female Korean college students tend to have much lower participation rates than their male counterparts. An effective means of increasing physical activity among female college students is sport participation. The purpose of this study is to incorporate three types of psychological needs from self-determination theory as precursor background variables into the theory of planned behavior to predict sport participation among female Korean college students. Our dataset consisted of 494 female undergraduate students attending Kyung Hee University in South Korea. Using structural equation modeling, the direct and indirect effects of attitude, subjective norm, perceived behavioral control, and psychological needs satisfaction such as competency, relatedness, and autonomy were examined. Although attitude towards and perceived behavioral control over sport participation were significantly associated with intention in all three models, subjective norm was not significantly associated with intention in any model. Satisfaction of the psychological needs for competency, relatedness, and autonomy had positive indirect effects on sport participation. This study underscores the importance of addressing the satisfaction of these three basic psychological needs when designing future sport promotion interventions for female college students.


Asunto(s)
Intención , Deportes/psicología , Estudiantes/psicología , Pueblo Asiatico , Actitud Frente a la Salud/etnología , Femenino , Humanos , Masculino , Modelos Psicológicos , República de Corea , Encuestas y Cuestionarios , Universidades
15.
ACS Nano ; 14(6): 7101-7110, 2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32501001

RESUMEN

Although ferroelectric composites have been reported to enhance the performance of triboelectric (TE) devices, their performances are still limited owing to randomly dispersed particles. Herein, we introduce high-performance TE sensors (TESs) based on ferroelectric multilayer nanocomposites with alternating poly(vinylidenefluoride-co-trifluoroethylene) (PVDF-TrFE) and BaTiO3 (BTO) nanoparticle (NP) layers. The multilayers comprising alternating soft/hard layers can induce stress concentration and increase the effective stress-induced polarization and interfacial polarization between organic and inorganic materials, leading to a dielectric constant (17.06) that is higher than those of pure PVDF-TrFE films (13.9) and single PVDF-TrFE/BTO nanocomposites (15.9) at 10 kHz. As a result, the multilayered TESs with alternating BTO NP layers exhibit TE currents increased by 2.3 and 1.5 times compared to pure PVDF-TrFE without BTO NPs and PVDF-TrFE/BTO nanocomposites without multilayer structures, respectively. The multilayered TESs exhibit a high pressure sensitivity of 0.94 V/kPa (48.7 nA/kPa) and output power density of 29.4 µWcm-2, enabling their application in the fabrication of highly sensitive healthcare monitoring devices and high-performance acoustic sensors. The suggested architecture of ferroelectric multilayer nanocomposites provides a robust platform for TE devices and self-powered wearable electronics.

16.
ACS Nano ; 14(1): 12-20, 2020 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-31913600

RESUMEN

Transfer printing of electronic functions on arbitrary surfaces is essential for next-generation applications of skin-attachable electronics, wearable sensors, and implantable/medical devices. For transfer printing of electronic functions on multidimensional surfaces, such as curved regions of the skin and different objects, various strategies have been devised based on the materials and structural design of electronic components and transfer stamps, such as ultrathin membranes or in-plane structures of electronic components, soft interfacial glues or adhesives between devices and surfaces, and smart transfer adhesives with bioinspired micro/nanostructures. These techniques enable high conformity of adhesion, mechanical robustness, and high compliance of electronic devices on arbitrary surfaces under mechanical deformation. In this Perspective, we provide an overview of recent transfer printing techniques and discuss their advantages and challenges. In addition, we report a recently developed transfer printing technique based on bioinspired smart adhesives with reversible adhesion, which enables compliant electronics on various arbitrary complex surfaces without performance degradation, providing solutions for various technical challenges remaining in transfer printing. Finally, we present potential applications of transfer printing and future perspectives for this emerging field.


Asunto(s)
Técnicas Biosensibles , Impresión Tridimensional , Dispositivos Electrónicos Vestibles , Electrónica , Humanos , Tamaño de la Partícula , Propiedades de Superficie
17.
Neurosurg Rev ; 43(4): 1163-1171, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31317284

RESUMEN

This study aimed to evaluate the safety and completeness of using intraoperative indocyanine green videoangiography (ICGV) combined with intraoperative angiography (IOA) for aneurysm clipping in a hybrid operating room (hOR). All patients who underwent microsurgical clipping in the hOR were identified from prospectively maintained neurosurgical databases. Medical charts and operative videos with ICGV and IOA were reviewed to determine the adequacy of clipping, and clinical and angiographic outcomes were retrospectively analyzed. Fifty-four cerebral aneurysms (ruptured, 31; unruptured, 23) in 50 patients (mean age, 59.4 ± 10.9 y; M:F, 22:28) were evaluated with ICGV and IOA during clipping. Additional IOA led to a clip adjustment during surgery in 9/54 (16.7%) aneurysms for which ICGV had been initially performed. Post-clip perforator compromise occurred in two (3.7%) cases, with a patient with an unruptured aneurysm experiencing permanent injury (grade 3 hemiparesis) and patient with a ruptured aneurysm experiencing transient deficit. Post-clip parent vessel stenosis occurred in one (1.9%) case; however, an ischemic event did not occur because the flow patency was identified by IOA. No other patients with unruptured aneurysms developed new neurologic deficits at discharge. Favorable outcomes (Glasgow Outcome Score [GOS], 4 or 5) were observed in 26/31 patients with ruptured aneurysms. Five patients had unfavorable outcomes (GOS, 2 or 3) from the initial insult. Post-treatment angiography within 1 week showed complete occlusion in 52 (96.3%) aneurysms and minor remnants in two (3.7%) aneurysms. Using combined ICGV and IOA in a hOR may improve the safety and completeness of microsurgical aneurysm clipping.


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Verde de Indocianina , Aneurisma Intracraneal/cirugía , Procedimientos Neuroquirúrgicos/métodos , Quirófanos/organización & administración , Anciano , Aneurisma Roto/cirugía , Isquemia Encefálica/etiología , Femenino , Escala de Consecuencias de Glasgow , Humanos , Verde de Indocianina/efectos adversos , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/efectos adversos , Seguridad del Paciente , Complicaciones Posoperatorias/epidemiología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resultado del Tratamiento
18.
Phytother Res ; 34(2): 359-367, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31680342

RESUMEN

Tumor angiogenesis and lymphangiogenesis are important processes in tumor progression and metastasis. The inhibitory effects of 3-O-acetyloleanolic acid (3AOA), a pentacyclic triterpenoid compound isolated from Vigna sinensis K., on tumor-induced angiogenesis and lymphangiogenesis in vitro and in vivo were studied. Angiopoietin-1 is an important angiogenic and lymphangiogenic factor secreted from colon carcinoma CT-26 cells under hypoxia conditions. 3AOA inhibited proliferation, migration, and tube formation of angiopoietin-1-treated human umbilical vein endothelial cells (HUVEC) and human lymphatic microvascular endothelial cells (HLMEC). 3AOA reduced angiogenesis and lymphangiogenesis in angiopoietin-1-stimulated Matrigel plugs. Also, 3AOA inhibited tumor growth and tumor-induced angiogenesis and lymphangiogenesis in an angiopoietin-1-induced CT-26 allograft colon carcinoma animal model. 3AOA inhibited activation of the angiopoietin-1 receptor Tie-2 and activation of the downstream signaling factors FAK, AKT, and ERK1/2 that are involved in the angiopoietin-1/Tie-2-signaling pathway. Thus, 3AOA has an inhibitory effect on angiogenesis and lymphangiogenesis induced by angiopoietin-1 both in vitro and in vivo, and the inhibitory effect of 3AOA is probably due to suppression of angiopoietin-1/Tie-2 signaling in HUVEC and HLMEC.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Angiopoyetina 1/metabolismo , Linfangiogénesis/efectos de los fármacos , Neovascularización Patológica/tratamiento farmacológico , Receptor TIE-2/metabolismo , Triterpenos/farmacología , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Femenino , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos BALB C , Neoplasias Experimentales/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos
19.
J Microbiol Biotechnol ; 29(9): 1383-1390, 2019 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-31434174

RESUMEN

In this study, we expressed cotA laccase from Bacillus subtilis on the surface of B. subtilis spores for efficient decolorization of synthetic dyes. The cotE, cotG, and cotY genes were used as anchoring motifs for efficient spore surface display of cotA laccase. Moreover, a His6 tag was inserted at the C-terminal end of cotA for the immunological detection of the expressed fusion protein. Appropriate expression of the CotE-CotA (74 kDa), CotG-CotA (76 kDa), and CotY-CotA (73 kDa) fusion proteins was confirmed by western blot. We verified the surface expression of each fusion protein on B. subtilis spore by flow cytometry. The decoloration rates of Acid Green 25 (anthraquinone dye) for the recombinant DB104 (pSDJH-EA), DB104 (pSDJH-GA), DB104 (pSDJH-YA), and the control DB104 spores were 48.75%, 16.12%, 21.10%, and 9.96%, respectively. DB104 (pSDJH-EA) showed the highest decolorization of Acid Green 25 and was subsequently tested on other synthetic dyes with different structures. The decolorization rates of the DB104 (pSDJH-EA) spore for Acid Red 18 (azo dye) and indigo carmine (indigo dye) were 18.58% and 43.20%, respectively. The optimum temperature for the decolorization of Acid Green 25 by the DB104 (pSDJH-EA) spore was found to be 50°C. Upon treatment with known laccase inhibitors, including EDTA, SDS, and NaN3, the decolorization rate of Acid Green 25 by the DB104 (pSDJH-EA) spore decreased by 23%, 80%, and 36%, respectively.


Asunto(s)
Antraquinonas/metabolismo , Bacillus subtilis/enzimología , Colorantes/metabolismo , Lacasa/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Inhibidores Enzimáticos/química , Expresión Génica , Cinética , Lacasa/antagonistas & inhibidores , Lacasa/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Esporas Bacterianas/enzimología , Esporas Bacterianas/genética , Esporas Bacterianas/metabolismo , Temperatura
20.
Adv Mater ; 31(25): e1808148, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31070272

RESUMEN

Biological tissues are multiresponsive and functional, and similar properties might be possible in synthetic systems by merging responsive polymers with hierarchical soft architectures. For example, mechanochromic polymers have applications in force-responsive colorimetric sensors and soft robotics, but their integration into sensitive, multifunctional devices remains challenging. Herein, a hierarchical nanoparticle-in-micropore (NP-MP) architecture in porous mechanochromic polymers, which enhances the mechanosensitivity and stretchability of mechanochromic electronic skins (e-skins), is reported. The hierarchical NP-MP structure results in stress-concentration-induced mechanochemical activation of mechanophores, significantly improving the mechanochromic sensitivity to both tensile strain and normal force (critical tensile strain: 50% and normal force: 1 N). Furthermore, the porous mechanochromic composites exhibit a reversible mechanochromism under a strain of 250%. This architecture enables a dual-mode mechanochromic e-skin for detecting static/dynamic forces via mechanochromism and triboelectricity. The hierarchical NP-MP architecture provides a general platform to develop mechanochromic composites with high sensitivity and stretchability.


Asunto(s)
Fenómenos Mecánicos , Nanopartículas , Dispositivos Electrónicos Vestibles , Color , Interacciones Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Porosidad , Estrés Mecánico , Resistencia a la Tracción
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