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1.
Adv Healthc Mater ; : e2402492, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363803

RESUMO

Smooth muscle cells (SMCs) sense and respond to mechanical stimuli in their extracellular microenvironments (ECMs), playing a crucial role in muscle tissue engineering. Increasing evidence from topological cues-mediated mechanotransduction of SMCs in ECMs has suggested some potential underlying mechanisms of how SMC functions and maturation are regulated by their mechanosensing leading to transduction. However, how the expression of yes-associated protein 1 (YAP) influences the phenotypic shift from synthetic to contractile is still controversial. Here, pseudo-3D topological alignments mimicking native muscle tissues are generated using laser-cutter engraving to explore the influence of topological cues on SMC mechanotransduction and maturation. The analysis of topological cue-mediated mechanotransduction and maturation marker expression revealed YAP is involved in mechanotransduction for SMCs cultured on cross-patterned substrates in the presence of cell-cell interactions. Moreover, these SMCs with YAP-linked mechanosensing showed higher expression of calponin, indicating a shift toward contractile phenotypes in vitro and in vivo. Furthermore, it showed skeletal muscle cells has different mechanosensing and maturation mechanisms compared to SMCs, revealing muscle type-dependent different sensing of topological cues, and converting into maturation-associated signaling cascades. This study provides insights into the regulation of SMC mechanotransduction and maturation by topological cues, suggesting the involvement of YAP-linked signaling pathways in this process.

3.
Sci Rep ; 12(1): 19149, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352018

RESUMO

With the development of wearable devices and soft electronics, the demand for stretchable piezoelectric energy harvesters (SPEHs) has increased. Energy harvesting can provide energy when large batteries or power sources cannot be employed, and stretchability provides a user-friendly experience. However, the performance of SPEHs remains low, which limits their application. In this study, a wearable SPEH is developed by adopting a kirigami structure on a polyvinylidene fluoride film. The performance of the SPEH is improved by rearranging the stress distribution throughout the film. This is conducted using two approaches: topological depolarization, which eliminates the opposite charge generation by thermal treatment, and optimization of the neutral axis, which maximizes the stress applied at the surface of the piezoelectric film. The SPEH performance is experimentally measured and compared with that of existing SPEHs. Using these two approaches, the stress was rearranged in both the x-y plane and z-direction, and the output voltage increased by 21.57% compared with that of the original film with the same stretching motion. The generated energy harvester was successfully applied to smart transmittance-changing contact lenses.

4.
Sci Total Environ ; 799: 149357, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34364280

RESUMO

In this study, the thermodynamic and structural characteristics of natural gas hydrates (NGHs) retrieved from gas hydrate mounds (ARAON Mound 03 (AM03) and ARAON Mound 06 (AM06)) in the Chukchi Sea in the Arctic region were investigated. The gas compositions, crystalline structure, and cage occupancy of the NGHs at AM03 and AM06 were experimentally measured using gas chromatography (GC), 13C nuclear magnetic resonance (NMR), Raman spectroscopy, and powder X-ray diffraction (PXRD). In the NGHs from AM03 and AM06, a significantly large fraction of CH4 (> 99%) and a very small amount of H2S were enclathrated in small (512) and large (51262) cages of sI hydrate. The NGHs from AM03 and AM06 were almost identical in composition, guest distributions, and existing environment to each other. The salinity of the residual pore water in the hydrate-bearing sediment (AM06) was measured to be 50.32‰, which was much higher than that of seawater (34.88‰). This abnormal salinity enrichment in the pore water of the low-permeability sediment might induce the dissociation of NGHs at a lower temperature than expected. The saturation changes in the NGHs that corresponded with an increase in the seawater temperature were also predicted on the basis of the salinity changes in the pore water. The experimental and predicted results of this study would be helpful for understanding the thermodynamic stability of NGHs and potential CH4-releasing phenomena in the Arctic region.


Assuntos
Gás Natural , Água , Dióxido de Carbono/análise , Salinidade , Termodinâmica
5.
ACS Nano ; 14(5): 5392-5399, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32275387

RESUMO

Structural colors that can be changed dynamically, using either plasmonic nanostructures or photonic crystals, are rapidly emerging research areas for stretchable sensors. Despite the wide applications of various techniques to achieve strain-responsive structural colors, important factors in the feasibility of strain sensors-such as their sensing mechanism, stability, and reproducibility-have not yet been explored. Here, we introduce a stretchable, diffractive, color-based wireless strain sensor that can measure strain using the entire visible spectrum, based on an array of cone-shaped nanostructures on the surface of an elastomeric substrate. By stretching or compressing the substrate, the diffractive color can be tuned according to the changing grating pitch. Using the proposed method, we designed three types of strain-sensing modes: large-deformation (maximum 100%) tensile strain, biaxial 2D strain, and shear strain (maximum 78%). The strain sensors were fabricated, and applicability to strain-sensing was evaluated.

6.
Appl Opt ; 56(6): 1701-1707, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28234379

RESUMO

We present a magneto-optic sensing system based on the "off-axis" optical probing technique to control the measurement sensitivity of magnets with various field strengths. The magnetic field is experimentally investigated in the absolute scale through a photonic calibration method with a standard electromagnet. Our all-dielectric magnetic field probe has a wide dynamic range (20 mT-3 T) with good responsivity and low probe invasiveness against the magnetic field being measured. Utilizing this magnetic-field-calibrated probing system, we obtain the magnetic field distribution of permanent magnets. Subsequently, we compare our results with numerical analyses to confirm the effectiveness of the probing system. Finally, we measure the intense magnetic field inside the bore of a 3.0-T clinical magnetic resonance imaging system with our probe.

7.
BMC Ophthalmol ; 12: 25, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22817759

RESUMO

BACKGROUND: To report two cases of atypical vitelliform macular dystrophy misdiagnosed as chronic central serous chorioretinopathy. CASE PRESENTATION: Two patients with incidentally discovered abnormalities of the retina without specific symptoms were referred to our hospital for consultation. Bilateral macula atrophic lesions were observed and optical coherence tomography revealed serous retinal detachment in the macula. Fluorescein angiography showed multiple leakages around the central hypofluorescent area and indocyanine green angiography showed partially dilated choroidal vessels. Fundus autofluorescence (FAF) showed a decreasing pattern of autofluorescence in the subretinal fluid area, and increasing autofluorescence at the border of the serous retinal detachment. Both patients were diagnosed with chronic central serous chorioretinopathy. Photodynamic therapy and intravitreal bevacizumab injection were administered for engorged choroidal vessels during follow-up, but neither patient showed improvement in symptoms or ophthalmologic findings. Based on re-evaluation by fundus photography, optical coherence tomography, fluorescein angiography, and comparison of the results of FAF with the first visit, vitelliform macular dystrophy was suspected and a definite diagnosis was made by electrooculography and genetic testing. CONCLUSION: In patients with continuous serous retinal detachment without response to photodynamic therapy or intravitreal bevacizumab injection, careful fundus exam and FAF can be used to diagnose atypical vitelliform macular dystrophy.


Assuntos
Coriorretinopatia Serosa Central/diagnóstico , Distrofia Macular Viteliforme/diagnóstico , Adulto , Doença Crônica , Erros de Diagnóstico , Angiofluoresceinografia , Fluorescência , Humanos , Verde de Indocianina , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica
8.
J Pharmacopuncture ; 15(3): 39-44, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25780646

RESUMO

OBJECTIVE: The purpose of this study is to report the effects of Chukyu (spine-healing) pharmacopuncture treatment in patients with lumbago and skelalgia. METHODS: This clinical study included 45 patients who were treated for lumbago and skelalgia at the Department of Acupuncture and Moxibusition, Dong-Eui University College of Oriental Medicine, from July 5, 2011, to January 31, 2012. Subjects were randomly divided into two groups: Chukyu (spinehealing)- pharmacopuncture-treated group (experimental group, n = 23) and normal saline-pharmacopuncture-treated group (control group, n = 22). Patients in the experimental group were treated with acupuncture and Chukyu (spine-healing) pharmacopuncture while those in the control group were treated with acupuncture and normal saline pharmacopuncture. To estimate the efficacy of controlling pain, we checked the visual analog scale [VAS], and to estimate the improvement of the symptoms, we evaluated by pain rating scale [PRS] and the Oswestry low-back pain disability index [ODI]. RESULTS: A comparison of the experimental and the control groups showed more significant improvements in the VAS, PRS, and ODI for the experimental group than for the control group. CONCLUSIONS: Chukyu (spine-healing) pharmacopuncture can be used for effective treatment in patients with lumbago and skelalgia.

9.
Ophthalmologica ; 226(3): 138-44, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21822008

RESUMO

AIM: To compare the effects of intravitreal bevacizumab on different morphologic patterns of diabetic macular edema (DME) classified using optical coherence tomography (OCT). MATERIALS AND METHODS: Medical records for 65 eyes of 48 patients were retrospectively reviewed, and each subject was classified as one of three DME types according to the OCT features: diffuse retinal thickening (DRT), cystoid macular edema (CME), serous retinal detachment (SRD). Subjects were given three monthly intravitreal injections of bevacizumab (1.25 mg/0.05 ml). The clinical course of best-corrected visual acuity (BCVA) with a logarithm of the minimum angle of resolution chart and central foveal thickness (CFT) using OCT was monitored for 12 months after the injections. On follow-up, injections were repeated if DME remained or was aggravated. RESULTS: Of the 65 eyes with DME, 29 eyes were of the DRT type, 21 of the CME type, and 15 of the SRD type. Before the injection, CFT and BCVA were, respectively, 377.1 ± 145.9 µm and 0.54 ± 0.36 in the DRT type, 427.7 ± 143.1 µm and 0.59 ± 0.42 in the CME type, and 485.1 ± 187.1 µm and 0.65 ± 0.27 in the SRD type; there was no significant difference in CFT and BCVA between DME types (p > 0.05). At 6 months, the changes in BCVA and CFT differed significantly between OCT types (p < 0.05). At 12 months, changes in CFT and BCVA from baseline were not significantly different between groups (p > 0.05). The DRT type was associated with a greater reduction in the CFT and greater BCVA improvement than the CME or SRD types. CONCLUSIONS: Three monthly injections of intravitreal bevacizumab seem to be effective treatment in the first 6 months, but the therapeutic effect is temporary and repeated injections of bevacizumab should be considered to maintain the therapeutic effect after 6 months. In addition, intravitreal injection of bevacizumab was more effective in the DRT type than in the CME or SRD types of DME.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Retinopatia Diabética/tratamento farmacológico , Edema Macular/tratamento farmacológico , Tomografia de Coerência Óptica , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Bevacizumab , Retinopatia Diabética/classificação , Retinopatia Diabética/patologia , Feminino , Humanos , Injeções Intravítreas , Edema Macular/classificação , Edema Macular/patologia , Masculino , Pessoa de Meia-Idade , Retratamento , Estudos Retrospectivos , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia
10.
Acta Ophthalmol ; 89(1): e52-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20560888

RESUMO

PURPOSE: To describe findings of spectral domain optical coherence tomography (SD-OCT) in the diagnosis of occult macular dystrophy (OMD). MATERIALS AND METHODS: Five visually disturbed patients who had shown normal findings in full field electroretinogram (ERG), fundus photography and fluorescein angiography but abnormal findings in multifocal ERG had undergone SD-OCT. The morphologic changes in retina and macular thickness were detected and imaged by SD-OCT. We analysed the results of SD-OCT including macular thickness, inner segment and outer segment (IS/OS) boundary and external limiting membrane (ELM). RESULTS: Mean age was 41.6 (22-63) in three male and two female patients in this study. Mean central foveal thickness was 142.9 (76-161) µm. All patients had shown decreased bowing of IS/OS boundary, and five of nine eyes were noted with disrupted IS/OS boundary of the photoreceptors according to SD-OCT. The interruption of external limiting membrane was noted in three of nine eyes. CONCLUSIONS: Spectral domain optical coherence tomography findings are useful in diagnosing OMD. Morphologic changes of the retina including deformity of the OS/IS boundary of the photoreceptors, disruption of the ELM and decreased foveal thickness may be important characteristics to consider when determining the pathophysiology and diagnosing criteria of OMD.


Assuntos
Degeneração Macular/diagnóstico , Tomografia de Coerência Óptica , Adulto , Eletrorretinografia , Feminino , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Retina/patologia , Adulto Jovem
11.
Bioresour Technol ; 101(10): 3602-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20080401

RESUMO

Cost-effective production of bacterial cellulose (BC) by Acetobacter sp. V6 was investigated in shake culture using glycerol as carbon source and its structural and physical properties were determined. In medium containing 3% (w/v) glycerol, BC production was 4.98+/-0.03g/l after 7 days. This value was 3.8-fold higher than the yield in the glucose medium. FT-IR spectra revealed that all the BC samples were highly crystalline and were cellulose type capital I, Ukrainian. The crystallinity index value of the BC produced was 9% higher in the glycerol medium than in the glucose medium. Scanning electron micrographs showed that BC from the glycerol medium was more compact than that from the glucose medium. Water-holding capacity and viscosity of BC from the glycerol medium had 61.3% and 22.4% lower values than those from the glucose medium. These results suggest that glycerol could be a potential low-cost substrate for BC production by Acetobacter sp. V6, leading to the reduction in the production cost.


Assuntos
Acetobacter/química , Celulose/química , Glicerol/química , Acetobacter/citologia , Meios de Cultura , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
12.
Cancer Lett ; 261(1): 84-92, 2008 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-18086515

RESUMO

The antimetastatic properties of soybean saponin were investigated by evaluating matrix metalloproteinase (MMP-2 and MMP-9) production in HT-1080 cells. The mRNA expression levels of MMP-2 and MMP-9 were determined by RT-PCR analysis. The levels of secreted MMP-2, MMP-9 and tissue inhibitor of metalloproteinase-2 (TIMP-2) were determined by gelatin zymography and/or ELISA. The invasion of a Matrigel-coated membrane by human fibrosarcoma HT-1080 and HT-29 colon cancer cells was quantitatively assessed by counting the migrated cells. The treatment of HT-1080 cells with soybean saponin inhibited the mRNA expression of and reduced the amounts of secreted MMP-2 and MMP-9, whereas it increased the amount of secreted TIMP-2 dose-dependently. Soybean saponin significantly inhibited the invasion of HT-1080 cells through a Matrigel-coated membrane. The antimetastatic properties by soybean saponin were further confirmed by in vivo mice experiment via the tail vein injection of CT-26 colon cancer cells after feeding the mice the dietary soybean saponin. The incidence of metastatic tumor colonization of lungs of mice moderately decreased 2 weeks after the tail vein injection of CT-26 cells. Our current data support the notion that soybean saponin inhibits tumor cell metastasis by suppressing MMP-2 and MMP-9 productions, and stimulating TIMP-2 secretion, thereby suggesting that soybean saponin has a chemopreventive property against cancer metastasis.


Assuntos
Neoplasias do Colo/enzimologia , Fibrossarcoma/enzimologia , Glycine max/química , Metaloproteinases da Matriz/metabolismo , Metástase Neoplásica/prevenção & controle , Saponinas/farmacologia , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Fibrossarcoma/patologia , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Inibidor Tecidual de Metaloproteinase-2/metabolismo
13.
J Spinal Disord Tech ; 17(5): 405-11, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15385881

RESUMO

OBJECTIVE: To observe metabolic differences between spinal tumor and other diseases in human spinal mass lesions, in vivo 1H magnetic resonance spectroscopy (MRS) was attempted to obtain metabolic signals in patients with various spinal mass lesions. METHODS: 1H nuclear magnetic resonance (NMR) spectra were obtained from 14 patients before surgery using a receive-only surface coil on a 1.5 T clinical magnetic resonance imaging (MRI) unit. MRS findings were compared with the histopathologic results from biopsy. In addition, tumor spectra were compared with the spectra of other benign diseases including disc herniation, which can mimic spinal cord tumor. In vitro 1H-NMR spectra were also collected from perchloric acid extracts of some spinal tumors. RESULTS: Typical water resonance line widths were in the 6- to 10-Hz range, but the metabolic signals observed were sufficiently resolved to be assigned from comparison with the 1H spectra of brain tissue. Choline was detected in all tumor spectra (n = 6) except ependymoma, whereas it was absent in other benign diseases including disc herniation (mimicking spinal cord tumors), dermoid cyst, tuberculosis, and non-multiple sclerosis myelitis. Spectral patterns of meningiomas, schwannomas, metastasis from renal cell carcinoma, and ependymomas in the spinal cord were similar to those of central nervous system (CNS) tumors. It was not possible to observe distinctive metabolic differences between benign diseases owing to relatively larger line broadening of some signals compared with that in CNS tissue. CONCLUSIONS: It appeared that acquisition of in vivo 1H-NMR signals was possible in human spinal mass lesions on a 1.5 T clinical MRI unit. Detection of choline only in the spinal tumors may indicate that there is some potential in using in vivo 1H-MRS to distinguish spinal tumors from disc herniation mimicking spinal cord tumors, non-multiple sclerosis myelitis, and dermoid cysts. On the basis of our NMR findings, however, it was not possible to distinguish between benign diseases.


Assuntos
Cisto Dermoide/diagnóstico , Ependimoma/diagnóstico , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Meningioma/diagnóstico , Neurilemoma/diagnóstico , Neoplasias da Medula Espinal/diagnóstico , Doenças da Coluna Vertebral/diagnóstico , Biomarcadores Tumorais , Biópsia , Colina/metabolismo , Cisto Dermoide/metabolismo , Cisto Dermoide/patologia , Diagnóstico Diferencial , Erros de Diagnóstico/prevenção & controle , Ependimoma/metabolismo , Ependimoma/patologia , Humanos , Deslocamento do Disco Intervertebral/diagnóstico , Deslocamento do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/fisiopatologia , Meningioma/metabolismo , Meningioma/patologia , Neurilemoma/metabolismo , Neurilemoma/patologia , Valor Preditivo dos Testes , Prótons , Reprodutibilidade dos Testes , Neoplasias da Medula Espinal/metabolismo , Neoplasias da Medula Espinal/patologia , Doenças da Coluna Vertebral/patologia
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