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1.
J Econ Entomol ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38757660

RESUMEN

The sweetpotato whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is challenging to control using chemical pesticides owing to its resistance to many insecticides. Thus, there has been an increasing demand for alternative control measures. Thus, this study evaluated the efficacy of a newly designed pest suction machine to manage whiteflies on tomato plants (Solanum lycopersicum L.) (Solanales: Solanaceae) in greenhouses over 2 seasons. The suction machine comprised a battery-powered cart with a mounted suction unit, an ultrasonic device, and green lights. Ultrasonic irradiation provided non-contact vibration, facilitating the movement of adult whiteflies away from the plants, and green lights attracted them to the suction device. This combination effectively captured whitefly adults, even with a weak suction force, saving electricity consumption. The efficacy of suction machine was further evaluated by measuring the number of whitefly adults caught by the machine and the number of adults and nymphs remaining on the tomato leaves. The whitefly population was considerably lower in the treated blocks than in the non-treated blocks in the autumn trial. The machine reduced the density of whitefly adults without using chemical pesticides. Although a lot of optimizations would be required, suction control is an additional and alternative strategy that may be incorporated in the integrated pest management of whiteflies on greenhouse tomato plants.

2.
PNAS Nexus ; 2(7): pgad207, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37404834

RESUMEN

Applications in chemistry, biology, medicine, and engineering require the large-scale manipulation of a wide range of chemicals, samples, and specimens. To achieve maximum efficiency, parallel control of microlitre droplets using automated techniques is essential. Electrowetting-on-dielectric (EWOD), which manipulates droplets using the imbalance of wetting on a substrate, is the most widely employed method. However, EWOD is limited in its capability to make droplets detach from the substrate (jumping), which hinders throughput and device integration. Here, we propose a novel microfluidic system based on focused ultrasound passing through a hydrophobic mesh with droplets resting on top. A phased array dynamically creates foci to manipulate droplets of up to 300 µL. This platform offers a jump height of up to 10 cm, a 27-fold improvement over conventional EWOD systems. In addition, droplets can be merged or split by pushing them against a hydrophobic knife. We demonstrate Suzuki-Miyaura cross-coupling using our platform, showing its potential for a wide range of chemical experiments. Biofouling in our system was lower than in conventional EWOD, demonstrating its high suitability for biological experiments. Focused ultrasound allows the manipulation of both solid and liquid targets. Our platform provides a foundation for the advancement of micro-robotics, additive manufacturing, and laboratory automation.

4.
Free Radic Biol Med ; 183: 89-103, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35318102

RESUMEN

Selenoprotein P (SELENOP) is a major selenium (Se)-containing protein (selenoprotein) in human plasma that is mainly synthesized in the liver. SELENOP transports Se to the cells, while SELENOP synthesized in peripheral tissues is incorporated in a paracrine/autocrine manner to maintain the levels of cellular selenoproteins, called the SELENOP cycle. Pancreatic ß cells, responsible for the synthesis and secretion of insulin, are known to express SELENOP. Here, using MIN6 cells as a mouse model for pancreatic ß cells and Selenop small interfering (si)RNA, we found that Selenop gene knockdown (KD) resulted in decreased cell viability, cellular pro/insulin levels, insulin secretion, and levels of several cellular selenoproteins, including glutathione peroxidase 4 (Gpx4) and selenoprotein K (Selenok). These dysfunctions induced by Selenop siRNA were recovered by the addition of Se. Ferroptosis-like cell death, regulated by Gpx4, was involved in the decrease of cell viability by Selenop KD, while stress-induced nascent granule degradation (SINGD), regulated by Selenok, was responsible for the decrease in proinsulin. SINGD was also observed in the pancreatic ß cells of Selenop knockout mice. These findings indicate a significant role of SELENOP expression for the function of pancreatic ß cells by maintaining the levels of cellular selenoproteins such as GPX4 and SELENOK.


Asunto(s)
Ferroptosis , Células Secretoras de Insulina , Selenio , Selenoproteína P , Animales , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/metabolismo , Células Secretoras de Insulina/metabolismo , Ratones , Selenio/metabolismo , Selenoproteína P/genética , Selenoproteína P/metabolismo
5.
Nucleic Acids Res ; 49(12): 6893-6907, 2021 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-34142161

RESUMEN

Selenoprotein P (SELENOP) is a major plasma selenoprotein that contains 10 Sec residues, which is encoded by the UGA stop codon. The mRNA for SELENOP has the unique property of containing two Sec insertion sequence (SECIS) elements, which is located in the 3' untranslated region (3'UTR). Here, we coincidentally identified a novel gene, CCDC152, by sequence analysis. This gene was located in the antisense region of the SELENOP gene, including the 3'UTR region in the genome. We demonstrated that this novel gene functioned as a long non-coding RNA (lncRNA) that decreased SELENOP protein levels via translational rather than transcriptional, regulation. We found that the CCDC152 RNA interacted specifically and directly with the SELENOP mRNA and inhibited its binding to the SECIS-binding protein 2, resulting in the decrease of ribosome binding. We termed this novel gene product lncRNA inhibitor of SELENOP translation (L-IST). Finally, we found that epigallocatechin gallate upregulated L-IST in vitro and in vivo, to suppress SELENOP protein levels. Here, we provide a new regulatory mechanism of SELENOP translation by an endogenous long antisense ncRNA.


Asunto(s)
Regulación de la Expresión Génica , Biosíntesis de Proteínas , ARN Largo no Codificante/metabolismo , Selenoproteína P/genética , Catequina/análogos & derivados , Catequina/farmacología , Línea Celular Tumoral , Regulación hacia Abajo , Humanos , ARN Largo no Codificante/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/antagonistas & inhibidores , Selenoproteína P/biosíntesis
6.
Sci Rep ; 11(1): 9832, 2021 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-33972601

RESUMEN

We recently found that tumor necrosis factor-α (TNF-α) may be involved in neuronal cell death induced by methylmercury in the mouse brain. Here, we examined the cells involved in the induction of TNF-α expression by methylmercury in the mouse brain by in situ hybridization. TNF-α-expressing cells were found throughout the brain and were identified as microglia by immunostaining for ionized calcium binding adaptor molecule 1 (Iba1). Methylmercury induced TNF-α expression in mouse primary microglia and mouse microglial cell line BV2. Knockdown of apoptosis signal-regulating kinase 1 (ASK1), an inflammatory cytokine up-regulator that is responsible for reactive oxygen species (ROS), decreased methylmercury-induced TNF-α expression through decreased phosphorylation of p38 MAP kinase in BV2 cells. Suppression of methylmercury-induced reactive oxygen species (ROS) by antioxidant treatment largely abolished the induction of TNF-α expression and phosphorylation of p38 by methylmercury in BV2 cells. Finally, in mouse brain slices, the TNF-α antagonist (WP9QY) inhibited neuronal cell death induced by methylmercury, as did the p38 inhibitor SB203580 and liposomal clodronate (a microglia-depleting agent). These results indicate that methylmercury induces mitochondrial ROS that are involved in activation of the ASK1/p38 pathway in microglia and that this is associated with induction of TNF-α expression and neuronal cell death.


Asunto(s)
Encéfalo/patología , Intoxicación del Sistema Nervioso por Mercurio/patología , Microglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Encéfalo/citología , Línea Celular , Ácido Clodrónico/farmacología , Modelos Animales de Enfermedad , Contaminantes Ambientales/administración & dosificación , Contaminantes Ambientales/toxicidad , Técnicas de Silenciamiento del Gen , Humanos , Imidazoles/farmacología , MAP Quinasa Quinasa Quinasa 5/genética , MAP Quinasa Quinasa Quinasa 5/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Masculino , Intoxicación del Sistema Nervioso por Mercurio/etiología , Compuestos de Metilmercurio/administración & dosificación , Compuestos de Metilmercurio/toxicidad , Ratones , Microglía/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neuronas/patología , Péptidos Cíclicos/farmacología , Fosforilación/efectos de los fármacos , Cultivo Primario de Células , Piridinas/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
7.
Life Sci ; 256: 118031, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32615186

RESUMEN

AIMS: We had previously reported that addition of putrescine to the culture medium was reported to reduce methylmercury toxicity in C17.2 neural stem cells. Here, we have examined the inhibition of methylmercury-induced cytotoxicity by putrescine using ODC1-overexpressing C17.2 cells. MATERIALS AND METHODS: We established stable ODC1-overexpressing C17.2 cells and evaluated methylmercury-induced apoptosis by examining the TUNEL assay and cleaved caspase-3 levels. Mitochondria-mediated apoptosis was also evaluated by reduction of mitochondrial membrane potential and recruitment of Bax and Bak to the mitochondria. KEY FINDINGS: ODC is encoded by ODC1 gene, and putrescine levels in ODC1-overexpressing cells were significantly higher than in control cells. Overexpression of ODC1 and addition of putrescine to the culture medium suppressed DNA fragmentation and caspase-3 activation, which are observed when apoptosis is induced by methylmercury. Moreover, mitochondrial dysfunction and reactive oxygen species (ROS) generation, caused by methylmercury, were also inhibited by the overexpression of ODC1 and putrescine; pretreatment with ODC inhibitor, however, promoted both ROS generation and apoptosis by methylmercury. Finally, we found that Bax and Bak, the apoptosis-promoting factors, to be increased in mitochondria, following methylmercury treatment, and the same was inhibited by overexpression of ODC1. These results suggest that overexpression of ODC1 may prevent mitochondria-mediated apoptosis by methylmercury via increase of putrescine levels. SIGNIFICANCE: Our findings provide important clues to clarify mechanisms involved in the defense against methylmercury toxicity and suggest novel biological functions of putrescine.


Asunto(s)
Compuestos de Metilmercurio/toxicidad , Mitocondrias/efectos de los fármacos , Células-Madre Neurales/efectos de los fármacos , Ornitina Descarboxilasa/genética , Putrescina/farmacología , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Etiquetado Corte-Fin in Situ , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Mitocondrias/patología , Células-Madre Neurales/patología
8.
Plast Reconstr Surg ; 145(2): 348e-359e, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31985636

RESUMEN

BACKGROUND: The authors developed a noncontact low-frequency ultrasound device that delivers high-intensity mechanical force based on phased-array technology. It may aid wound healing because it is likely to be associated with lower risks of infection and heat-induced pain compared with conventional ultrasound methods. The authors hypothesized that the microdeformation it induces accelerates wound epithelialization. Its effects on key wound-healing processes (angiogenesis, collagen accumulation, and angiogenesis-related gene transcription) were also examined. METHODS: Immediately after wounding, bilateral acute wounds in C57BL/6J mice were noncontact low-frequency ultrasound- and sham-stimulated for 1 hour/day for 3 consecutive days (10 Hz/90.6 Pa). Wound closure (epithelialization) was recorded every 2 days as the percentage change in wound area relative to baseline. Wound tissue was procured on days 2, 5, 7, and 14 (five to six per time point) and subjected to histopathology with hematoxylin and eosin and Masson trichrome staining, CD31 immunohistochemistry, and quantitative polymerase-chain reaction analysis. RESULTS: Compared to sham-treated wounds, ultrasound/phased-array-treated wounds exhibited significantly accelerated epithelialization (65 ± 27 percent versus 30 ± 33 percent closure), angiogenesis (4.6 ± 1.7 percent versus 2.2 ± 1.0 percent CD31 area), and collagen deposition (44 ± 14 percent versus 28 ± 13 percent collagen density) on days 5, 2, and 5, respectively (all p < 0.05). The expression of Notch ligand delta-like 1 protein (Dll1) and Notch1, which participate in angiogenesis, was transiently enhanced by treatment on days 2 and 5, respectively. CONCLUSIONS: The authors' noncontact low-frequency ultrasound phased-array device improved the wound-healing rate. It was associated with increased early neovascularization that was followed by high levels of collagen-matrix production and epithelialization. The device may expand the mechanotherapeutic proangiogenesis field, thereby helping stimulate a revolution in infected wound care.


Asunto(s)
Piel/lesiones , Terapia por Ultrasonido/métodos , Cicatrización de Heridas/fisiología , Heridas y Lesiones/terapia , Animales , Colágeno/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica/fisiología , Piel/metabolismo , Heridas y Lesiones/metabolismo , Heridas y Lesiones/patología
9.
Org Lett ; 21(24): 10081-10084, 2019 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-31808701

RESUMEN

A Rh-catalyzed asymmetric intramolecular Buchner ring expansion of α-alkyl-α-diazoesters has been developed. The present protocol generates a 5,7-fused ring system in an enantioselective manner while minimizing ß-hydrogen migration, which has been a competing reaction when using α-alkyl-α-diazoesters. The ester functionality at the bridgehead position would be a useful synthetic handle for further derivatization to complex molecules including natural products.

10.
Environ Toxicol Pharmacol ; 71: 103216, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31260942

RESUMEN

Methylmercury is an environmental pollutant that shows selective toxicity to the central nervous system. We previously reported that brain-specific expression of chemokine CCL3 increases in mice administered methylmercury. However, the relationship between CCL3 and methylmercury toxicity has not been elucidated. Here, we confirmed that induction of CCL3 expression occurs before pathological change by methylmercury treatment was observed in the mouse brain. This induction was also observed in C17.2 mouse neural stem cells before methylmercury-induced cytotoxicity. In addition, cells in which CCL3 was knocked-down showed higher methylmercury sensitivity than did control cells. Moreover, activation of transcription factor NF-κB was observed following methylmercury treatment, and methylmercury-mediated induction of CCL3 expression was partially suppressed by knockdown of p65, an NF-κB subunit. Our results suggest that NF-κB plays a role in the induction of methylmercury-mediated CCL3 expression and that this action may be a cellular response to methylmercury toxicity.


Asunto(s)
Quimiocina CCL3/biosíntesis , Contaminantes Ambientales/toxicidad , Compuestos de Metilmercurio/toxicidad , FN-kappa B/biosíntesis , Células-Madre Neurales/efectos de los fármacos , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cerebelo/efectos de los fármacos , Cerebelo/metabolismo , Cerebelo/patología , Cerebro/efectos de los fármacos , Cerebro/metabolismo , Cerebro/patología , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Células-Madre Neurales/metabolismo , Células-Madre Neurales/patología
11.
J Toxicol Sci ; 44(7): 471-479, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31270303

RESUMEN

M1-microglia (neurotoxic microglia) regulate neuronal development and cell death and are involved in many pathologies in the brain. Although organotypic brain slice cultures are widely used to study the crosstalk between neurons and microglia, little is known about the properties of microglia in the mouse cerebral cortex slices. Here, we aimed to optimize the mouse cerebral slice cultures that reflect microglial functions and evaluate the effects of neurotoxic metals on M1-microglial activation. Most microglia in the cerebral slices prepared from postnatal day (P) 7 mice were similar to mature microglia in adult mice brains, but those in the slices prepared from P2 mice were immature, which is a conventional preparation condition. The degree of expression of M1-microglial markers (CD16 and CD32) and inflammatory cytokines (tumor necrosis factor-α and interleukin-1ß) by lipopolysaccharide, a representative microglia activator, in the cerebral slices of P7 mice were higher than that in the slices of P2 mice. These results indicate that M1-microglial activation can be evaluated more accurately in the cerebral slices of P7 mice than in those of P2 mice. Therefore, we next examined the effects of various neurotoxic metals on M1-microglial activation using the cerebral slices of P7 mice and found that methylmercury stimulated the activation to M1-microglia, but arsenite, lead, and tributyltin did not induce such activation. Altogether, the optimized mouse cerebral slice cultures used in this study can be a helpful tool to study the influence of various chemicals on the central nervous system in the presence of functionally mature microglia.


Asunto(s)
Corteza Cerebral/citología , Metales/toxicidad , Microglía/efectos de los fármacos , Microglía/fisiología , Animales , Animales Recién Nacidos , Arsenitos/toxicidad , Células Cultivadas , Corteza Cerebral/metabolismo , Citocinas/metabolismo , Expresión Génica , Mediadores de Inflamación/metabolismo , Plomo/toxicidad , Compuestos de Metilmercurio/toxicidad , Ratones Endogámicos C57BL , Microglía/metabolismo , Neuronas/fisiología , Receptores de IgG/genética , Receptores de IgG/metabolismo , Compuestos de Trialquiltina/toxicidad
12.
Sci Rep ; 9(1): 4631, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30874621

RESUMEN

Methylmercury is an environmental pollutant that causes specific and serious damage to the central nervous system. We have previously shown that C-C motif chemokine ligand 4 (CCL4) protects cultured neural cells from methylmercury toxicity and expression of CCL4 is specifically induced in mouse brain by methylmercury. In this study, we examined the transcriptional regulatory mechanism that induces CCL4 expression by methylmercury using C17.2 mouse neural stem cells. The promoter region of the CCL4 gene was analyzed by a reporter assay, revealing that the region up to 50 bp upstream from the transcription start site was necessary for inducing expression of CCL4 by methylmercury. Nine transcription factors that might bind to this upstream region and be involved in the induction of CCL4 expression by methylmercury were selected, and the induction of CCL4 expression by methylmercury was suppressed by the knockdown of serum response factor (SRF). In addition, the nuclear level of SRF was elevated by methylmercury, and an increase in the amount bound to the CCL4 gene promoter was also observed. Furthermore, we examined the upstream signaling pathway involved in the induction of CCL4 expression by SRF, and confirmed that activation of p38 and ERK, which are part of the MAPK pathway, are involved. These results suggest that methylmercury induces the expression of CCL4 by activating SRF via the p38 and ERK signaling pathway. Our findings are important for elucidating the mechanism involved in the brain-specific induction of CCL4 expression by methylmercury.


Asunto(s)
Quimiocina CCL4/metabolismo , Compuestos de Metilmercurio/efectos adversos , Factor de Respuesta Sérica/metabolismo , Animales , Encéfalo/metabolismo , Línea Celular , Células Cultivadas , Quimiocina CCL4/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Sistema de Señalización de MAP Quinasas , Compuestos de Metilmercurio/metabolismo , Compuestos de Metilmercurio/toxicidad , Ratones , FN-kappa B/metabolismo , Células-Madre Neurales/metabolismo , Regiones Promotoras Genéticas/genética , Factor de Respuesta Sérica/fisiología , Transducción de Señal , Factores de Transcripción/metabolismo
13.
Sci Rep ; 8(1): 13680, 2018 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-30194310

RESUMEN

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

14.
Sci Rep ; 8(1): 11085, 2018 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-30038295

RESUMEN

Rapidly adapting type I (RA-I) mechanoreceptors play an important role in sensing the low-frequency vibration aspects of touch. The structure of the RA-I mechanoreceptor is extremely complex regardless of its small size, limiting our understanding of its mechanotransduction. As a result of the emergence of bioengineering, we previously proposed an in vitro bioengineering approach for RA-I receptors to overcome this limitation. Currently, the in vitro bioengineering approach for the RA-I receptor is not realizable given the lack of knowledge of its morphogenesis. This paper demonstrates our first attempt to interpret the cellular morphogenesis of the RA-I receptor. We found indications of extrinsic mechanical force nearby the RA-I receptor in the developing fingertip. Using a mechanical compression device, the axon of dorsal root ganglion (DRG) neurons buckled in vitro into a profile that resembled the morphology of the RA-I receptor. This work encourages further implementation of this bioengineering approach in tactile receptor-related research.


Asunto(s)
Mecanorreceptores/metabolismo , Tacto/fisiología , Animales , Axones/metabolismo , Fenómenos Biomecánicos , Simulación por Computador , Dermis/metabolismo , Femenino , Colágenos Fibrilares/metabolismo , Ganglios Espinales/metabolismo , Ratones , Embarazo
15.
Sci Rep ; 8(1): 7541, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29765152

RESUMEN

Body ownership can be modulated through illusory visual-tactile integration or visual-motor synchronicity/contingency. Recently, it has been reported that illusory ownership of an invisible body can be induced by illusory visual-tactile integration from a first-person view. We aimed to test whether a similar illusory ownership of the invisible body could be induced by the active method of visual-motor synchronicity and if the illusory invisible body could be experienced in front of and facing away from the observer. Participants observed left and right white gloves and socks in front of them, at a distance of 2 m, in a virtual room through a head-mounted display. The white gloves and socks were synchronized with the observers' actions. In the experiments, we tested the effect of synchronization, and compared this to a whole-body avatar, measuring self-localization drift. We observed that visual hands and feet were sufficient to induce illusory body ownership, and this effect was as strong as using a whole-body avatar.


Asunto(s)
Ilusiones/psicología , Percepción del Tacto/fisiología , Percepción Visual/fisiología , Pie , Mano , Cuerpo Humano , Humanos , Ilusiones/fisiología , Masculino , Propiocepción/fisiología , Percepción Espacial , Adulto Joven
16.
PLoS One ; 12(12): e0189293, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29220415

RESUMEN

The feeling of touch is an essential human sensation. Four types of mechanoreceptors (i.e., FA-I, SA-I, FA-II, and SA-II) in human skin signalize physical properties, such as shape, size, and texture, of an object that is touched and transmit the signal to the brain. Previous studies attempted to investigate the mechanical properties of skin microstructure and their effect on mechanoreceptors by using finite element modeling. However, very few studies have focused on the three-dimensional microstructure of dermal papillae, and this is related to that of FA-I receptors. A gap exists between conventional 2D models of dermal papillae and the natural configuration, which corresponds to a complex and uneven structure with depth. In this study, the three-dimensional microstructure of dermal papillae is modeled, and the differences between two-dimensional and three-dimensional aspects of dermal papillae on the strain energy density at receptor positions are examined. The three-dimensional microstructure has a focalizing effect and a localizing effect. Results also reveal the potential usefulness of these effects for tactile sensor design, and this may improve edge discrimination.


Asunto(s)
Mecanorreceptores/metabolismo , Piel/metabolismo , Tacto , Calibración , Análisis de Elementos Finitos , Humanos , Modelos Biológicos , Piel/ultraestructura , Viscosidad
17.
Chem Commun (Camb) ; 53(50): 6784-6787, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28597903

RESUMEN

Dye-sensitized photoelectrochemical cells (DSPECs) composed of a new near-infrared BODIPY dye D1 that is co-deposited with a ruthenium water oxidation catalyst C1 have been fabricated. The devices at pH 7.2 showed an excellent Faradaic efficiency of H2 production (65.8%) that was 5.4 times larger than that of a triphenylamine photosensitizer D2 and C1-coadsorbed cell.

18.
IEEE Trans Haptics ; 9(4): 483-491, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27254872

RESUMEN

Meissner corpuscles are the fast adapting type I (FA-I) mechanoreceptor that locates at the dermal papillae of skin. The Meissner corpuscle is well known for its complex structure, consisting of spiral axons, lamellar cells, and a collagen capsule. Fluorescent microscopy has become a convenient method for observing the Meissner corpuscle and its inner structure. This method requires preparing samples with fingertip cross-sections and performing antibody staining before observation. Various kinds of microscopy can be used for observation, such as confocal microscopy, transmission electron microscopy (TEM), or scanning electron microscopy (SEM). Although the anatomical shape, distribution, and components of Meissner corpuscle are recognized, they have been mostly determined from observations of fixed tissues. Therefore, knowledge of mechanical transduction is limited by the lack of in vivo experiments and individual differences among samples. In this study, we propose a novel less invasive imaging method that incorporates a staining technique with lipophilic carbocyanine [Formula: see text] and two-photon microscopy. This combination allows us to repetitively observe the Meissner corpuscle in a living mouse.


Asunto(s)
Carbocianinas , Colorantes , Miembro Anterior/fisiología , Mecanorreceptores/fisiología , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Dedos del Pie/fisiología , Animales , Ratones , Ratones Endogámicos ICR
19.
IEEE Comput Graph Appl ; 34(4): 42-51, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25051569

RESUMEN

Specular reflection plays an important role in an image's appearance. However, LCDs don't have sufficient contrast to express specular reflection, and ordinary projector screens only have diffuse-reflection surfaces. A new display system projects ultrasound waves to dynamically change the reflection state of a screen made of a colloidal substance--soap film. The system uses time division multiplexing of the diffuse and specular states to produce realistic appearances. It employs an optical illusion that exploits the characteristics of human sight. Optical measurements and a user study validated this approach's effectiveness.

20.
PLoS One ; 9(5): e97590, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24849371

RESUMEN

The essence of levitation technology is the countervailing of gravity. It is known that an ultrasound standing wave is capable of suspending small particles at its sound pressure nodes. The acoustic axis of the ultrasound beam in conventional studies was parallel to the gravitational force, and the levitated objects were manipulated along the fixed axis (i.e. one-dimensionally) by controlling the phases or frequencies of bolted Langevin-type transducers. In the present study, we considered extended acoustic manipulation whereby millimetre-sized particles were levitated and moved three-dimensionally by localised ultrasonic standing waves, which were generated by ultrasonic phased arrays. Our manipulation system has two original features. One is the direction of the ultrasound beam, which is arbitrary because the force acting toward its centre is also utilised. The other is the manipulation principle by which a localised standing wave is generated at an arbitrary position and moved three-dimensionally by opposed and ultrasonic phased arrays. We experimentally confirmed that expanded-polystyrene particles of 0.6 mm, 1 mm, and 2 mm in diameter could be manipulated by our proposed method.


Asunto(s)
Aire , Ultrasonido/instrumentación , Tamaño de la Partícula , Poliestirenos/química
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