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1.
Artigo em Inglês | MEDLINE | ID: mdl-37030735

RESUMO

Contralateral controlled functional electrical stimulation (CCFES) can induce simultaneous movements in patients' bilateral hands. It has been clinically proven to be effective in improving hand motor control and dexterity. sEMG and bending sensor-based data gloves for detecting patients' motor intent have been developed with limitations. sEMG sensor signals are unstable and susceptible to noise. Data gloves composed of bending sensors require complicated calibration and tend to have data drift. In this paper, a LiDAR-based system for hand CCFES is proposed. The method utilized LiDAR to detect the patient's motion intention without contact in CCFES systems. It has been clinically proven that LiDARs can effectively distinguish the different motion amplitudes of hand gestures as quantitative evaluation sensors of functional electrical stimulation (FES). Training data for classifiers were collected from 9 healthy individuals and 15 stroke patients performing 4 gestures, including hand opening, fist clenching, wrist extension, and wrist flexion. The support vector machine (SVM), linear discriminant analysis (LDA), and k-nearest neighbor (kNN) were verified for their classification performance in offline hand gesture recognition tests. Experiments were also conducted on 6 stroke volunteers to evaluate gestures triggered by FES. The SVM classifier showed excellent classification performance for four hand gestures, with an average F1-score of 0.97 ± 0.05 in offline tests. As for online gesture recognition, an average F1-score of 0.92 ± 0.09 was obtained. In the evaluation experiments, between data from 50% and 100% movement amplitude, paired t-tests showed significant differences. The experimental results indicated that the proposed system showed promise for hand rehabilitation.


Assuntos
Acidente Vascular Cerebral , Extremidade Superior , Humanos , Punho/fisiologia , Movimento/fisiologia , Movimento (Física) , Gestos , Mãos , Eletromiografia/métodos , Algoritmos
2.
IEEE Trans Biomed Eng ; 70(6): 1815-1825, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37015681

RESUMO

OBJECTIVE: This paper aimed to develop an orthosis to apply a compensating force to improve the stability of the glenohumeral joint without resisting arm movement. METHODS: The proposed orthosis was based on a parallelogram structure to provide a pair of compensating forces to the glenohumeral joint center. Theoretical analysis was used to evaluate the additional moments caused by glenohumeral joint center shifting. Then, an experimental evaluation platform, composed of a torque sensor, a force sensor, and a 3D printed arm, was set up to assess the additional moments and compensating force. Finally, the proposed orthosis was compared with the traditional orthosis to compare the subluxation reduction and the movement restriction when worn by stroke patients. RESULTS: There was only a maximum additional moment of 0.87 Nm for the glenohumeral center shifting. During 3D printed arm movement, the moment correlation coefficient between with and without the proposed orthosis was greater than 0.98, and the compensating force was larger than 90% of the arm weight. The proposed orthosis reduced subluxation by 12.5±3.5 mm, and the traditional orthosis reduced subluxation by 7.7±2.2 mm, indicating that the subluxation reduction of the proposed orthosis was more effective ( ). Meanwhile, the proposed orthosis's motion restriction joint was significantly smaller than traditional orthosis ( ). CONCLUSION: The proposed orthosis provided sufficient gravity compensation without resisting arm movement. SIGNIFICANCE: The proposed orthosis can improve the shoulder's stability during shoulder movement, potentially improving the rehabilitation effect of patients with shoulder subluxation.


Assuntos
Luxação do Ombro , Articulação do Ombro , Humanos , Ombro , Luxação do Ombro/terapia , Luxação do Ombro/etiologia , Aparelhos Ortopédicos/efeitos adversos , Extremidade Superior , Fenômenos Biomecânicos , Amplitude de Movimento Articular
3.
Cell Res ; 32(12): 1047-1067, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36307579

RESUMO

Pituitary neuroendocrine tumor (PitNET) is one of the most common intracranial tumors. Due to its extensive tumor heterogeneity and the lack of high-quality tissues for biomarker discovery, the causative molecular mechanisms are far from being fully defined. Therefore, more studies are needed to improve the current clinicopathological classification system, and advanced treatment strategies such as targeted therapy and immunotherapy are yet to be explored. Here, we performed the largest integrative genomics, transcriptomics, proteomics, and phosphoproteomics analysis reported to date for a cohort of 200 PitNET patients. Genomics data indicate that GNAS copy number gain can serve as a reliable diagnostic marker for hyperproliferation of the PIT1 lineage. Proteomics-based classification of PitNETs identified 7 clusters, among which, tumors overexpressing epithelial-mesenchymal transition (EMT) markers clustered into a more invasive subgroup. Further analysis identified potential therapeutic targets, including CDK6, TWIST1, EGFR, and VEGFR2, for different clusters. Immune subtyping to explore the potential for application of immunotherapy in PitNET identified an association between alterations in the JAK1-STAT1-PDL1 axis and immune exhaustion, and between changes in the JAK3-STAT6-FOS/JUN axis and immune infiltration. These identified molecular markers and alternations in various clusters/subtypes were further confirmed in an independent cohort of 750 PitNET patients. This proteogenomic analysis across traditional histological boundaries improves our current understanding of PitNET pathophysiology and suggests novel therapeutic targets and strategies.


Assuntos
Tumores Neuroendócrinos , Neoplasias Hipofisárias , Proteogenômica , Humanos , Tumores Neuroendócrinos/genética , Neoplasias Hipofisárias/genética , Transcriptoma/genética , Transição Epitelial-Mesenquimal
4.
Chem Commun (Camb) ; 58(82): 11539-11542, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36155688

RESUMO

A pyridyl-functionalized mesoporous graphene is developed to accommodate sulfur for Al-S batteries, which can significantly reduce the voltage hysteresis to ∼0.43 V. The reaction kinetics of the Al-S battery are accelerated by the catalyst-free carbon host, ascribed to both the mesoporous graphene structure and the covalently functionalized pyridyl groups.

5.
Small ; 18(14): e2107608, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35182010

RESUMO

Titanium-based anode materials have achieved much progress with the wide studies in lithium-ion batteries. However, these known materials usually possess high discharge voltage platforms and limited energy densities. Herein, a titanium-based oxide of Na2 TiGeO5 with layered structure, two-dimensional lamellar frame and exposed highly active (001) facet, exhibiting good electrochemical performance in terms of high capacity (410 mAh g-1 with a current density of 50 mA g-1 ), excellent rate capability and cycling stability with no obvious capacity attenuation after 4000 cycles, is reported. The appropriate discharge voltage plateau at around 0.2 V endows the Na2 TiGeO5 anode material high security compared with graphite and high energy density compared with spinel Li4 Ti5 O12 . Combining the electrochemical tests and the density functional theory calculations, the Li+ storage mechanism of Na2 TiGeO5 is elucidated and the conversion reaction process is revealed. More importantly, this study provides a way to develop low-voltage and high-capacity titanium-based anode materials for efficient energy storage.

6.
Food Funct ; 11(9): 7817-7829, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32808642

RESUMO

It is widely believed that grape seed proanthocyanidin extract (GSPE) exerts antioxidant and anti-inflammatory effects. Dietary supplementation with GSPE has been reported to alleviate colitis signs in mice, but the mechanisms involved require further exploration. The present study investigated how the oral administration of GSPE ameliorates colitis signs and reduces colitis-associated inflammation. C57BL/6 mice were treated with GSPE for 21 days. During the final 7 days of treatment, the mice were administered dextran sulfate sodium (DSS) dissolved in drinking water to induce experimental colitis. We found that GSPE treatment improved DSS-induced colitis, which was evidenced by decreases in disease activity index (DAI) scores, pathological scores, and oxidative stress and increases in zonula occludens-1 (ZO-1), occludin, and claudin-1 mRNA levels of colon tissue. Notably, the proinflammatory cytokines TNF-α and IL-1ß were significantly downregulated as a result of GSPE treatment in colon tissues. GSPE treatment also reduced NLR family pyrin domain-containing 3 (NLRP3) inflammasome mRNA levels of colon tissue. Furthermore, an analysis of 16S rRNA sequences showed that GSPE rebalanced the DSS-damaged gut microbiota, including reducing Bacteroidetes, Dubosiella, and Veillonella, increasing Verrucomicrobia and Akkermansia, and elevating the Firmicutes to Bacteroidetes ratio. In conclusion, GSPE supplementation alleviates DSS-induced colitis by modulating inflammatory cytokines and oxidation stress, maintaining the intestinal barrier, and improving the microbial community. These results indicate that GSPE might be a new dietary strategy for the treatment of ulcerative colitis.


Assuntos
Colite/induzido quimicamente , Colite/tratamento farmacológico , Citocinas/metabolismo , Sulfato de Dextrana/efeitos adversos , Microbioma Gastrointestinal/efeitos dos fármacos , Extrato de Sementes de Uva/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proantocianidinas/farmacologia , Animais , Colite Ulcerativa , Colo/metabolismo , Fezes/microbiologia , Glutationa , Inflamassomos/metabolismo , Interleucina-1beta , Intestinos/patologia , Masculino , Malondialdeído , Camundongos , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos , RNA Ribossômico 16S , Superóxido Dismutase , Fator de Necrose Tumoral alfa/metabolismo , Proteína da Zônula de Oclusão-1
7.
Food Funct ; 11(5): 3964-3974, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400787

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory bowel disease whose prevalence is increasing globally. A synbiotic has probiotic and prebiotic components and is regarded as a promising candidate for alleviating UC-associated inflammation. The purpose of this study is to determine whether there is an additive efficacy between the probiotic Bifidobacterium infantis (B. infantis) and the prebiotic xylooligosaccharide (XOS) against UC. C57BL/6 mice were treated with B. infantis, XOS, or synbiotic (combination of B. infantis and XOS) for 21 d. During the final 7 d of treatment, the mice were administered dextran sulfate sodium (DSS) dissolved in drinking water to induce colitis. All treatments decreased the disease activity index (DAI) and pathological scores, and synbiotic treatment was more efficacious than either the probiotic or prebiotic alone. Compared with the DSS-induced colitis group, all treatment groups significantly downregulated the proinflammatory cytokines TNF-α and IL-1ß, and synbiotic treatment significantly upregulated the anti-inflammatory cytokine IL-10 in the colon tissues. Furthermore, all treatments significantly reduced the NLR family pyrin domain containing 3 (NLRP3) inflammasome mRNA level in the colon tissues. All treatments significantly inhibited oxidative stress and increased zonula occludens-1 (ZO-1), occludin, and claudin-1 tight junction (TJ) molecule mRNA levels in the colon tissues. Therefore, the observed efficacy of synbiotics against colitis may be explained by the additive combination of the direct anti-inflammatory effects of the probiotic and prebiotic components and their ability to fortify colonic epithelial barrier integrity. Our findings suggest that a synbiotic is a promising dietary supplement or functional food for the effective management of UC.


Assuntos
Bifidobacterium longum subspecies infantis , Colite Ulcerativa/induzido quimicamente , Sulfato de Dextrana/toxicidade , Glucuronatos/administração & dosagem , Oligossacarídeos/administração & dosagem , Simbióticos , Animais , Claudina-1/genética , Claudina-1/metabolismo , Citocinas/genética , Citocinas/metabolismo , Suplementos Nutricionais , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ocludina/genética , Ocludina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína da Zônula de Oclusão-1/genética , Proteína da Zônula de Oclusão-1/metabolismo
8.
Nanomaterials (Basel) ; 8(12)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30486493

RESUMO

TiO2 is one of the most attractive semiconductors for use as a photoanode for photoelectrochemical (PEC) water oxidation. However, the large-scale application of TiO2 photoanodes is restricted due to a short hole diffusion length and low electron mobility, which can be addressed by metal doping and surface decorating. In this paper we report the successful synthesis of hierarchical Ta doped TiO2 nanorod arrays, with nanoparticles on the top (Ta:TiO2), on F-doped tin oxide (FTO) glass by a hydrothermal method, and its application as photoanodes for photoelectrochemical water oxidation. It has been found that the incorporation of Ta5+ in the TiO2 lattice can decrease the diameter of surface TiO2 nanoparticles. Ta:TiO2-140, obtained with a moderate Ta concentration, yields a photocurrent of ∼1.36 mA cm-2 at 1.23 V vs. a reversible hydrogen electrode (RHE) under FTO side illumination. The large photocurrent is attributed to the large interface area of the surface TiO2 nanoparticles and the good electron conductivity due to Ta doping. Besides, the electron trap-free model illustrates that Ta:TiO2 affords higher transport speed and lower electron resistance when under FTO side illumination.

9.
Nanoscale ; 10(41): 19367-19374, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30307005

RESUMO

Owing to its excellent chemical stability and low cost, titanium dioxide (TiO2) has been widely studied as a photoanode for photoelectrochemical (PEC) water splitting. However, TiO2's practical applications in solar energy-to-synthetic fuel conversion processes have been constrained by its inherently poor ability to transport photogenerated electrons and holes. In this paper, we report Ta-doped porous TiO2 nanorod arrays on Ta foil (Ta-PTNA) that do not possess this issue and that can thus efficiently photoelectrocatalyze water oxidation, helping the production of H2 (a clean fuel) from water at the expense of solar light. The materials are synthesized by a new, facile synthetic approach involving the hydrothermal treatment of a TiO2 precursor with Ta foil, without seeds and templates, and followed by calcination of the product. Besides serving as a source of Ta dopant atoms, Ta foil is found to play a vital role in the formation of nanopores in the materials. The material obtained with hydrothermal treatment at 180 °C for 10 h (Ta-PTNA-10), in particular, affords very large photocurrent density and very high photoconversion efficiency (0.32% at 0.79 V vs. RHE, which is better than those of many previously reported photocatalysts and ∼4 times larger than that of undoped TiO2 nanorod arrays). Ta-PTNAs' remarkable PEC catalytic performance is found to be due to their nanoporous structure and high electronic conductivity.

10.
Chem Commun (Camb) ; 54(23): 2858-2861, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29480299

RESUMO

A carbon- and binder-free Ti@Ru material is synthesized through a facile and controllable strategy. A Ti@Ru based Li-O2 battery can effectively avoid the subsidiary reactions, and can be reversibly and continuously cycled for more than 500 cycles with an efficiency ca. 100%, exhibiting an ultra-cycling stability.

11.
Nanoscale ; 9(28): 9913-9920, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28678289

RESUMO

A tri-layered photoelectrode for dye-sensitized solar cells (DSSCs) is assembled using single crystal hollow TiO2 nanoparticles (HTNPs), sub-micro hollow TiO2 mesospheres (SHTMSs) and hierarchical TiO2 microspheres (HTMSs). The bottom layer composed of single crystal hollow TiO2 nanoparticles serves to absorb dye molecules, harvest light due to its hollow structure and keep a better mechanical contact with FTO conducting glass; the middle layer consisting of sub-micro hollow mesospheres works as a multifunctional layer due to its high dye adsorption ability, strong light trapping and scattering ability and slow recombination rates; and the top layer consisting of hierarchical microspheres enhances light scattering. The DSSCs made of photoanodes with a tripartite-layer structure (Film 4) show a superior photoconversion efficiency (PCE) of 9.24%, which is 7.4% higher than a single layered photoanode composed of HTNPs (Film 1: 8.90%), 4.6% higher than a double layer-based electrode consisting of HTNPs and SHTMSs (Film 2: 9.03%) and 2.6% higher than a double layer-based electrode made of HTNPs and HTMSs (Film 3: 9.11%). The significant improvements in the PCE for tri-layered TiO2 photoanodes are mainly because of the combined effects of their higher light scattering ability, long electron lifetime, fast electron transport rate, efficient charge collection and a considerable surface area with high dye-loading capability. This study confirms that the facile tri-layered photoanode is an interesting structure for high-efficiency DSSCs.

12.
ACS Appl Mater Interfaces ; 9(1): 354-361, 2017 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-27976848

RESUMO

Transition metal oxides caused much attention owing to the scientific interests and potential applications in energy storage systems. In this study, a free-standing three-dimensional (3D) chestnut-like TiO2@α-Fe2O3 core-shell nanostructure (TFN) is rationally synthesized and utilized as a carbon-free electrode for lithium-ion batteries (LIBs). Two new interfaces between anatase TiO2 and α-Fe2O3 are observed and supposed to provide synergistic effect. The TiO2 microsphere framework significantly improves the mechanical stability, while the α-Fe2O3 provides large capacity. The abundant boundary structures offer the possibility for interfacial lithium storage and electron transport. The as-prepared TFN delivers a high capacity of 820 mAh g-1 even after 1000 continuous cycles with a Coulombic efficiency of ca. 99% at a current of 500 mA g-1, which is better than the works reported previously. A thin gel-like SEI (solid electrolyte interphase) film and Fe0 phase yielded during charge/discharge cycling have been confirmed which makes it possible to alleviate the volumetric change and enhance the electronic conductivity. This confirmation is helpful for understanding the mechanism of lithium-ion storage in α-Fe2O3-based materials. The as-prepared free-standing TFN with excellent stability and high capacity can be an appropriate candidate for carbon-free anode material in LIBs.

13.
Nanoscale ; 7(33): 13888-97, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26219743

RESUMO

A TiO2 film has been facilely grown on a Ti foil via a general and simple acid vapor oxidation (AVO) strategy. Based on detailed characterization by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), we found that the TiO2 film was composed of anatase nanoarrays highly oriented along their <001> direction, resulting in a large exposed {001} top surface on the film. The growth mechanism based on a topotactic transformation was proposed according to a careful study of time-dependent experimental results. Resulting from the evaluation of photocatalytic performance compared with a commercial TiO2 photocatalyst (Degussa P25), the as-prepared oriented anatase TiO2 film showed higher efficiency for degradation of atrazine and acid orange II (AOII). The performance of photocatalysis is highly relevant to the preferential orientation. The efficient photocatalysis could be attributed to the highly reactive {001} facets on the anatase nanoarrays with super-hydrophilicity.

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