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1.
Small ; : e2311736, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552227

RESUMO

Nanomaterial-based yarns have been actively developed owing to their advantageous features, namely, high surface-area-to-volume ratios, flexibility, and unusual material characteristics such as anisotropy in electrical/thermal conductivity. The superior properties of the nanomaterials can be directly imparted and scaled-up to macro-sized structures. However, most nanomaterial-based yarns have thus far, been fabricated with only organic materials such as polymers, graphene, and carbon nanotubes. This paper presents a novel fabrication method for fully inorganic nanoribbon yarn, expanding its applicability by bundling highly aligned and suspended nanoribbons made from various inorganic materials (e.g., Au, Pd, Ni, Al, Pt, WO3, SnO2, NiO, In2O3, and CuO). The process involves depositing the target inorganic material on a nanoline mold, followed by suspension through plasma etching of the nanoline mold, and twisting using a custom-built yarning machine. Nanoribbon yarn structures of various functional inorganic materials are utilized for chemical sensors (Pd-based H2 and metal oxides (MOx)-based green gas sensors) and green energy transducers (water splitting electrodes/triboelectric nanogenerators). This method is expected to provide a comprehensive fabrication strategy for versatile inorganic nanomaterials-based yarns.

2.
Molecules ; 26(8)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918660

RESUMO

Angelica gigas Nakai root contains decursin which exerts beneficial properties such as anti-amnesic and anti-inflammatory activities. Until now, however, the neuroprotective effects of decursin against transient ischemic injury in the forebrain have been insufficiently investigated. Here, we revealed that post-treatment with decursin and the root extract saved pyramidal neurons in the hippocampus following transient ischemia for 5 min in gerbil forebrain. Through high-performance liquid chromatography, we defined that decursin was contained in the extract as 7.3 ± 0.2%. Based on this, we post-treated with 350 mg/kg of extract, which is the corresponding dosage of 25 mg/kg of decursin that exerted neuroprotection in gerbil hippocampus against the ischemia. In addition, behavioral tests were conducted to evaluate ischemia-induced dysfunctions via tests of spatial memory (by the 8-arm radial maze test) and learning memory (by the passive avoidance test), and post-treatment with the extract and decursin attenuated ischemia-induced memory impairments. Furthermore, we carried out histochemistry, immunohistochemistry, and double immunohistofluorescence. Pyramidal neurons located in the subfield cornu ammonis 1 (CA1) among the hippocampal subfields were dead at 5 days after the ischemia; however, treatment with the extract and decursin saved the pyramidal neurons after ischemia. Immunoglobulin G (IgG, an indicator of extravasation), which is not found in the parenchyma in normal brain tissue, was apparently shown in CA1 parenchyma from 2 days after the ischemia, but IgG leakage was dramatically attenuated in the CA1 parenchyma treated with the extract and decursin. Furthermore, astrocyte endfeet, which are a component of the blood-brain barrier (BBB), were severely damaged at 5 days after the ischemia; however, post-treatment with the extract and decursin dramatically attenuated the damage of the endfeet. In brief, therapeutic treatment of the extract of Angelica gigas Nakai root and decursin after 5 min transient forebrain ischemia protected hippocampal neurons from the ischemia, showing that ischemia-induced BBB leakage and damage of astrocyte endfeet was significantly attenuated by the extract and decursin. Based on these findings, we suggest that Angelica gigas Nakai root containing decursin can be employed as a pharmaceutical composition to develop a therapeutic strategy for brain ischemic injury.


Assuntos
Angelica/química , Astrócitos/patologia , Benzopiranos/uso terapêutico , Barreira Hematoencefálica/patologia , Butiratos/uso terapêutico , Ataque Isquêmico Transitório/patologia , Extratos Vegetais/uso terapêutico , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Benzopiranos/química , Benzopiranos/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Butiratos/química , Butiratos/farmacologia , Gerbillinae , Proteína Glial Fibrilar Ácida/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Imunoglobulina G/metabolismo , Masculino , Neuraminidase/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/farmacologia , Padrões de Referência , Memória Espacial/efeitos dos fármacos
3.
Molecules ; 26(18)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34576901

RESUMO

Transient ischemia in brains causes neuronal damage, gliosis, and blood-brain barrier (BBB) breakdown, which is related to ischemia-induced brain dysfunction. Populus species have various pharmacological properties including antioxidant and anti-inflammatory activities. In this study, we found that phenolic compounds were rich in Populus tomentiglandulosa extract and examined the effects of Populus tomentiglandulosa extract on neuronal damage/death, astrogliosis, and BBB breakdown in the striatum, which is related to motor behavior, following 15-min transient ischemia in the forebrain in gerbils. The gerbils were pre-treated with 50, 100, and 200 mg/kg of the extract. The latter showed significant effects against ischemia-reperfusion injury. Ischemia-induced hyperactivity using spontaneous motor activity test was significantly attenuated by the treatment. Striatal cells (neurons) were dead at five days after the ischemia; however, pre-treatment with the extract protected the striatal cells from ischemia/reperfusion injury. Ischemia-induced reactive astrogliosis was significantly alleviated, in particular, astrocyte end feet, which are a component of BBB, were significantly preserved. Immunoglobulin G, which is not found in intact brain parenchyma, was apparently shown (an indicator of extravasation) in striatal parenchyma at five days after the ischemia, but IgG leakage was dramatically attenuated in the parenchyma by the pre-treatment. Based on these findings, we suggest that Populus tomentiglandulosa extract rich in phenolic compounds can be employed as a pharmaceutical composition to develop a preventive material against brain ischemic injury.


Assuntos
Astrócitos , Barreira Hematoencefálica , Gerbillinae , Polifenóis , Populus , Animais , Morte Celular/efeitos dos fármacos , Hipocampo/metabolismo , Neurônios/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico
4.
Adv Sci (Weinh) ; 10(35): e2302775, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37752815

RESUMO

The growing demand for soft intelligent systems, which have the potential to be used in a variety of fields such as wearable technology and human-robot interaction systems, has spurred the development of advanced soft transducers. Among soft systems, sensor-actuator hybrid systems are considered the most promising due to their effective and efficient performance, resulting from the synergistic and complementary interaction between their sensor and actuator components. Recent research on integrated sensor and actuator systems has resulted in a range of conceptual and practical soft systems. This review article provides a comprehensive analysis of recent advances in sensor and actuator integrated systems, which are grouped into three categories based on their primary functions: i) actuator-assisted sensors for intelligent detection, ii) sensor-assisted actuators for intelligent movement, and iii) sensor-actuator interactive devices for a hybrid of intelligent detection and movement. In addition, several bottlenecks in current studies are discussed, and prospective outlooks, including potential applications, are presented. This categorization and analysis will pave the way for the advancement and commercialization of sensor and actuator-integrated systems.

5.
Microsc Res Tech ; 85(1): 364-372, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34453869

RESUMO

Preclinical experiments to analyze the trabecular space of spongy bones using small animals are required for the evaluation and treatment of patients with osteoporosis (OP). We performed ovariectomy to create OP models. A total of four mice were used. Ovariectomized group (OVX, n = 2) in which both ovaries were resected at random, and the sham operated group (SHAM, n = 2) performed surgery without resecting the ovaries. We propose a study that enables OP analysis by analyzing tibia microstructures of OVX and SHAM using synchrotron radiation (SR). SR imaging is a technology capable of irradiating an extremely small object in the order of several tens of nanometers using a nondestructive method at the microscopic level. Unlike previous imaging diagnoses (staining, micro-CT [Computed Tomography]) it was possible to preserve the real shape and analyze bone microstructures in real-time and analyze and evaluate spongy bones to secure data and increase the reliability of OP analysis. We were able to confirm the possibility of OP diagnosis through experimental animals for spongy bone damage related to bone mineral density. Therefore, we aimed to provide a rehabilitation and medicine therapy intervention method through basic research on the evaluation of OP diagnosis through human-based segmentation of challenging spongy bones while supplementing the limitations of existing imaging methods. RESEARCH HIGHLIGHTS: We present an analysis of osteoporosis through spongy bone using phase-contrast X-ray source. Unlike existing methods, it is possible to analyze the internal microstructure of the tibia with this method. This is an objective mechanism for OP and a basis for rehabilitation.


Assuntos
Osteoporose , Síncrotrons , Animais , Densidade Óssea , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Modelos Animais , Osteoporose/diagnóstico por imagem , Ovariectomia , Reprodutibilidade dos Testes , Tíbia/diagnóstico por imagem , Microtomografia por Raio-X
6.
Antioxidants (Basel) ; 10(4)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924188

RESUMO

Salicin is a major natural compound of willow bark and displays diverse beneficial biological properties, such as antioxidant activity. However, little information available for the neuroprotective potential of salicin against ischemic brain injury has been reported. Thus, this study was performed to investigate the neuroprotective potential of salicin against ischemia and reperfusion (IR) injury and its mechanisms in the hippocampus using a gerbil model of 5-min transient ischemia (TI) in the forebrain, in which a massive loss (death) of pyramidal neurons cells occurred in the subfield Cornu Ammonis 1 (CA1) among the hippocampal subregions (CA1-3) at 5 days after TI. To examine neuroprotection by salicin, gerbils were pretreated with salicin alone or together with LY294002, which is a phosphatidylinositol 3-kinase (PI3K) inhibitor, once daily for 3 days before TI. Treatment with 20 mg/kg of salicin significantly protected CA1 pyramidal neurons against the ischemic injury. Treatment with 20 mg/kg of salicin significantly reduced the TI-induced increase in superoxide anion generation and lipid peroxidation in the CA1 pyramidal neurons after TI. The treatment also reinstated the TI-induced decrease in superoxide dismutases (SOD1 and SOD2), catalase, and glutathione peroxidase in the CA1 pyramidal cells after TI. Moreover, salicin treatment significantly elevated the levels of phosphorylation of Akt and glycogen synthase kinase-3ß (GSK3ß), which is a major downstream target of PI3K, in the ischemic CA1. Notably, the neuroprotective effect of salicin was abolished by LY294002. Taken together, these findings clearly indicate that salicin protects against ischemic brain injury by attenuating oxidative stress and activating the PI3K/Akt/GSK3ß pathway.

7.
Chin Med J (Engl) ; 128(12): 1649-54, 2015 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-26063368

RESUMO

BACKGROUND: Oenanthe javanica (O. javanica) has been known to have high antioxidant properties via scavenging reactive oxygen species. We examined the effect of O. javanica extract (OJE) on antioxidant enzymes in the rat liver. METHODS: We examined the effect of the OJE on copper, zinc-superoxide dismutase (SOD1), manganese superoxide dismutase (SOD2), catalase (CAT), and glutathione peroxidase (GPx) in the rat liver using immunohistochemistry and western blot analysis. Sprague-Dawley rats were randomly assigned to three groups; (1) normal diet fed group (normal-group), (2) diet containing ascorbic acid (AA)-fed group (AA-group) as a positive control, (3) diet containing OJE-fed group (OJE-group). RESULTS: In this study, no histopathological finding in the rat liver was found in all the experimental groups. Numbers of SOD1, SOD2, CAT, and GPx immunoreactive cells and their protein levels were significantly increased in the AA-fed group compared with those in the normal-group. On the other hand, in the OJE-group, numbers of SOD1, SOD2, CAT, and GPx immunoreactive cells in the liver were significantly increased by about 190%, 478%, 685%, and 346%, respectively, compared with those in the AA-group. In addition, protein levels of SOD1, SOD2, CAT, and GPx in the OJE-group were also significantly much higher than those in the AA-group. CONCLUSION: OJE significantly increased expressions of SOD1 and SOD2, CAT, and GPx in the liver cells of the rat, and these suggests that significant enhancements of endogenous enzymatic antioxidants by OJE might be a legitimate strategy for decreasing oxidative stresses in the liver.


Assuntos
Fígado/efeitos dos fármacos , Fígado/enzimologia , Oenanthe/química , Extratos Vegetais/farmacologia , Animais , Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Imuno-Histoquímica , Fígado/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Glutationa Peroxidase GPX1
8.
Lab Anim Res ; 28(3): 165-70, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23091516

RESUMO

Alpha-synuclein (α-syn) is a presynaptic protein that is richly expressed in the central and peripheral nervous systems of mammals, and it is related to the pathogenesis of Parkinson's disease and other neurodegenerative disorders. In the present study, we compared the distribution of the immunoreactivity of α-syn and its related gliosis in the spinal cord of young adult (2-3 years) and aged (10-12 years) beagle dogs. We discovered that α-syn immunoreactivity was present in many neurons in the thoracic level of the aged spinal cord, however, its protein level was not distinct inform that of the adult spinal cord. In addition, ionized calcium-binding adapter molecule-1 (a marker for microglia) immunoreactivity, and not glial fibrillary acidic protein (a marker for astrocytes) immunoreactivity, was somewhat increased in the aged group compared to the adult group. These results indicate that α-syn immunoreactivity was not dramatically changed in the dog spinal cord during aging.

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