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1.
Int Arch Allergy Immunol ; 184(8): 727-735, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37231959

RESUMO

INTRODUCTION: Allergic rhinitis (AR) is identified as a multifactorial disease caused by the interaction of genes and surroundings, which is difficult to cure. MicroRNAs were reported to be engaged in AR development. Here, we aimed to seek the anti-inflammatory effects and regulatory mechanism of miR-193b-3p in AR. METHODS: Mucosal tissues from AR patients and healthy volunteers were collected, and human nasal epithelial cells (HNECs) were treated with IL-13 to establish a cell model of AR. The gene expression of miR-193b-3p, ETS1, TLR4, GM-CSF, eotaxin, and MUC5AC was determined by RT-qPCR. The protein levels of ETS1 and TLR4 were examined using Western blot. Enzyme-linked immunosorbent assay was performed to measure protein concentration of GM-CSF, eotaxin, and MUC5AC in cell supernatant. Dual luciferase assay was applied to verify the interaction among miR-193b-3p, ETS1, and TLR4. RESULTS: The expression of miR-193b-3p was declined in clinical samples from AR patients and in IL-13-induced HNECs, while the mRNA and protein levels of ETS1 and TLR4 were elevated. MiR-193b-3p overexpression or ETS1 silencing notably decreased the mRNA and protein levels of GM-CSF, eotaxin, and MUC5AC in IL-13-treated HNECs. Mechanistically, miR-193b-3p directly combined with ETS1 to silence ETS1 expression. ETS1 promoted the transcriptional activity of TLR4 through interacting with TLR4 promoter. Furthermore, rescue experiments revealed that ETS1 overexpression abolished miR-193b-3p sufficiency-mediated suppression of the mRNA and protein levels of GM-CSF, eotaxin, and MUC5AC in IL-13-treated HNECs. Similarly, TLR4 overexpression compromised the inhibitory impacts of ETS1 downregulation on the mRNA and protein levels of GM-CSF, eotaxin, and MUC5AC in IL-13-induced HNECs. DISCUSSION: MiR-193b-3p repressed IL-13-induced inflammatory response in HNECs by suppressing ETS1/TLR4 axis, which indicated that miR-193b-3p might be a therapeutic target for AR treatment.


Assuntos
MicroRNAs , Rinite Alérgica , Humanos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Receptor 4 Toll-Like/genética , Interleucina-13 , MicroRNAs/genética , MicroRNAs/metabolismo , Rinite Alérgica/genética , Inflamação , RNA Mensageiro , Proteína Proto-Oncogênica c-ets-1/genética
2.
Inflammopharmacology ; 31(3): 1551-1558, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37010717

RESUMO

INTRODUCTION: Endometritis is the inflammatory condition of the uterus. Citral, a component of lemongrass oil, is known to exhibit anti-inflammatory activity. AIM: The effects of citral on LPS-induced endometritis were tested and the mechanisms were investigated. METHODS: LPS-induced endometritis mice model was established and the effects of citral were detected using this model. Inflammatory cytokines were tested by ELISA. Ferroptosis was assessed by detecting GSH, ATP, MDA, and Fe2+ levels. Signaling pathway was tested by western blot analysis. RESULTS: Citral prevented LPS-induced endometritis through attenuating uterine pathological changes and inflammatory cytokine release. Meanwhile, citral prevents LPS-induced ferroptosis through attenuating MDA and Fe2+ levels, as well as increasing ATP and GSH levels. Furthermore, citral up-regulated Nrf2 and HO-1 expression and attenuated NF-κB activation. In addition, in Nrf2 knockdown mice, the inhibitory roles of citral on ferroptosis and endometritis were largely reversed. CONCLUSION: Taken together, citral inhibited LPS-induced endometritis through preventing ferroptosis, which were regulated by Nrf2 signaling pathway.


Assuntos
Endometrite , Ferroptose , Humanos , Feminino , Camundongos , Animais , Endometrite/induzido quimicamente , Endometrite/prevenção & controle , Lipopolissacarídeos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Citocinas/metabolismo , Trifosfato de Adenosina
3.
Appl Opt ; 61(29): 8678-8687, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36256004

RESUMO

Evaluating the stress field based on photoelasticity is of vital significance in engineering fields. To achieve the goal of efficiently demodulating stress distribution and to overcome the limitations of conventional methods, it is essential to develop a deep learning method to simplify and accelerate the process of image acquisition and processing. A framework is proposed to enhance prediction accuracy. By adopting Resnet as the backbone, applying U-Net architecture, and adding a physical constraint module, our model recovers the stress field with higher structural similarity. Under different conditions, our model performs robustly despite complicated geometry and a large stress range. The results prove the universality and effectiveness of our model and offer an opportunity for instant stress detection.

4.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2617-2622, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34047111

RESUMO

The origins of 9 species of the Chinese medicinal materials in the 2015 edition of the Chinese pharmacopoeia(ChP) has revised in the 2020 edition of ChP. The revision is based on the investigation and textual research on the problems found after screening the original plants, animals or minerals of all the Chinese medicinal materials in the 2015 edition. Among them the Chinese names of Alismatis Rhizoma, Cassiae Semen, Coicis Semen, Corydalis Bungeanae Herba and Echinopsis Radix all do not match to the Latin scientific names, and also do not match the name of the actual medicinal origins. In addition, Alismatis Rhizoma has the omission of original plant. There is confusion about the Chinese name and the family name of the original insect of Cera Chinensis. The original mineral of Gypsum Fibrosum has the wrong group names. Alumstone and melanterite, the original mineral of Alumen and Melanteritum respectively, of which the group names are missing. To solve these problems, field survey and literature research were conducted on the medicinal materials and their origins. The source of these problems are explored. The correct origins and the Chinese names or Latin names are all determined according to the research results to the situation, in which the Chinese and Latin names of the original plants of the medicinal materials do not match. The correct family name and group name are obtained through textual research by taxonomy if the names are confused or mis-sing. The scientific evidence and correct results of revision in the 2020 edition of ChP are determined at last.


Assuntos
Coix , Medicamentos de Ervas Chinesas , Animais , China , Medicina Tradicional Chinesa , Rizoma
5.
Zhongguo Zhong Yao Za Zhi ; 43(21): 4361-4364, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30583642

RESUMO

The original plant species of Fructus Aurantii are multitudinous and complex, and their requirements to the growing environment is strict. In order to clarify the original plant species and geographical distribution of Fructus Aurantii which recorded in the standards and circulated, used in commodity. The national and local standards of Chinese medicinal materials were collected and the original plants of Fructus Aurantii recoded in standards were found. Ten original plant species of Fructus Aurantii (including varieties of cultivars, the same below) were recorded in the Chinese pharmacopoeia and six local standards of Zhejiang, Yunnan and Guizhou etc. The producing areas and commodity in markets of Fructus Aurantii were investigated. The growth environment and geographical distribution of them were analyzed. There are six types of Fructus Aurantii i.e., Fructus Aurantii Chuan, Fructus Aurantii Xiang, Fructus Aurantii Jiang, Fructus Aurantii Qu, Fructus Aurantii Su, Fructus Aurantii Wen, and nineteen species of original plants in the practical commodities. There are four major Fructus Aurantii producing areas: Sichuan Basin, Dongting Lake Plain, Poyang Lake Plain, Jinqu Basin and its surrounding hilly areas. All of them are located in the area of the east longitude 104° to 121° and the northern latitudes 27° to 31°. There is a certain difference between the actual commodity and the standards of medicinal materials. It is suggested that the traditional mainstream types of Fructus Aurantii with fine quality should be accepted into Chinese Pharmacopoeia, and the types with poor quality should be withdrawn from Chinese Pharmacopoeia.


Assuntos
Citrus/classificação , Citrus/crescimento & desenvolvimento , China , Medicamentos de Ervas Chinesas , Frutas , Geografia
6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(5): 733-739, 2018 10 25.
Artigo em Chinês | MEDLINE | ID: mdl-30370712

RESUMO

The performance of intelligent prosthetic knee has an important effect on the realization of physiological gait of transfemoral amputees. A new type of single axis hydraulic damping knee prosthesis was designed based on the analysis of physiological gait. The training methods of the stance and swing phase were proposed. Knee prosthesis test was done through simulation and measurement device. The control target of peak flexion angle during swing of knee prosthesis is chosen to be 60-70°. When the damper valve closure was 0%, maximum swing-phase knee flexion angle of knee prosthesis were (86±2)°, (91±3)° and (97±3)° with the speed of 0.8 m/s, 1.2 m/s and 1.8 m/s, respectively. Once the valve closure was changed, maximum swing-phase knee flexion angle with different speeds could be adjusted between 60° and 70° and the required valve closure percentage were separately 25%, 40% and 70%. The damping adjustment law of intelligent knee prosthesis to achieve physiological gait was revealed.

7.
J Surg Res ; 200(1): 315-23, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26375505

RESUMO

BACKGROUND: Sepsis is a major clinical challenge in modern medicine, representing one of the leading causes of death in developed countries. The syndrome is a consequence of a dysregulated immune response, including early uncontrolled systemic inflammation and prolonged immunosuppression in the late phase. The present study was conducted to investigate the therapeutic effects of astragaloside IV (ASI-IV) on the cecal ligation and puncture (CLP)-induced sepsis in mice. MATERIALS AND METHODS: C57BL/6 mice were randomly divided into sham control + vehicle, CLP + vehicle, and CLP + ASI-IV groups. ASI-IV (3 mg/kg) was intravenously injected 1 h after CLP surgery. Survival rate, bacterial clearance, inflammatory mediators, phagocytes emigration, histopathology, and lymphocyte apoptosis were examined. The effects of ASI-IV on peritoneal macrophage activation and its underlying mechanisms were also evaluated. RESULTS: We reported that treatment with ASI-IV significantly improved survival in septic mice. In agreement with this protective effect, the pathologic damage that was typically seen in lung and spleen was ameliorated; the level of bacterial burden was lessened; inflammatory cytokines and chemokines in circulation were profoundly reduced; lymphocyte apoptosis was inhibited. ASI-IV suppressed LPS-induced macrophage activation through inhibiting NF-κB and ERK1/2 signaling pathways. CONCLUSIONS: ASI-IV protected mice against polymicrobial sepsis by inhibiting inflammatory response and lymphocyte apoptosis. Therefore, ASI-IV might provide a novel therapeutic approach for septic patients.


Assuntos
Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Linfócitos/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Saponinas/farmacologia , Sepse/tratamento farmacológico , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/uso terapêutico , Biomarcadores/metabolismo , Western Blotting , Citocinas/sangue , Medicamentos de Ervas Chinesas/uso terapêutico , Injeções Intravenosas , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Fagócitos/efeitos dos fármacos , Substâncias Protetoras/uso terapêutico , Distribuição Aleatória , Saponinas/uso terapêutico , Sepse/microbiologia , Sepse/mortalidade , Triterpenos/uso terapêutico
8.
Inorg Chem ; 54(1): 183-91, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25526316

RESUMO

Electronic coupling across a bridging ligand between a chromophore and a catalyst center has an important influence on biological and synthetic photocatalytic processes. Structural and associated electronic modifications of ligands may improve the efficiency of photocatalytic transformations of organic substrates. Two ruthenium-based supramolecular assemblies based on a chromophore-catalyst dyad containing a Ru-aqua complex and its chloro form as the catalytic components were synthesized and structurally characterized, and their spectroscopic and electrochemical properties were investigated. Under visible light irradiation and in the presence of [Co(NH3)5Cl]Cl2 as a sacrificial electron acceptor, both complexes exhibited good photocatalytic activity toward oxidation of sulfide into the corresponding sulfoxide with high efficiency and >99% product selectivity in neutral aqueous solution. The Ru-aqua complex assembly was more efficient than the chloro complex. Isotopic labeling experiments using (18)O-labeled water demonstrated the oxygen atom transfer from the water to the organic substrate, likely through the formation of an active intermediate, Ru(IV)═O.

9.
Chemistry ; 20(26): 8054-61, 2014 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-24888489

RESUMO

Four new charge-neutral ruthenium(II) complexes containing dianionic Schiff base and isoquinoline or 4-picoline ligands were synthesized and characterized by NMR and ESI-MS spectroscopies, elemental analysis, and X-ray diffraction. The complexes exhibited excellent chemical water oxidation activity and high stability under acidic conditions (pH 1.0) using (NH4)2Ce(NO3)6 as a sacrificial electron acceptor. The high catalytic activities of these complexes for water oxidation were sustained for more than 10 h at low concentrations. High turnover numbers of up to 3200 were achieved. A water nucleophilic attack mechanism was proposed. A Ru(V)=O intermediate was detected during the catalytic cycle by high-resolution mass spectrometry.

10.
Chemistry ; 20(43): 13957-64, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25205065

RESUMO

Two mononuclear ruthenium complexes [Ru(H2tcbp)(isoq)2] (1) and [Ru(H2tcbp)(pic)2] (2) (H4tcbp=4,4',6,6'-tetracarboxy-2,2'-bipyridine, isoq=isoquinoline, pic=4-picoline) are synthesized and fully characterized. Two spare carboxyl groups on the 4,4'-positions are introduced to enhance the solubility of 1 and 2 in water and to simultaneously allow them to tether to the electrode surface by an ester linkage. The photochemical, electrochemical, and photoelectrochemical water oxidation performance of 1 in neutral aqueous solution is investigated. Under electrochemical conditions, water oxidation is conducted on the deposited indium-tin-oxide anode, and a turnover number higher than 15,000 per water oxidation catalyst (WOC) 1 is obtained during 10 h of electrolysis under 1.42 V vs. NHE, corresponding to a turnover frequency of 0.41 s(-1). The low overpotential (0.17 V) of electrochemical water oxidation for 1 in the homogeneous solution enables water oxidation under visible light by using [Ru(bpy)3](2+) (P1) (bpy=2,2'-bipyridine) or [Ru(bpy)2(4,4'-(COOEt)2-bpy)](2+) (P2) as a photosensitizer. In a three-component system containing 1 or 2 as a light-driven WOC, P1 or P2 as a photosensitizer, and Na2S2O8 or [CoCl(NH3)5]Cl2 as a sacrificial electron acceptor, a high turnover frequency of 0.81 s(-1) and a turnover number of up to 600 for 1 under different catalytic conditions are achieved. In a photoelectrochemical system, the WOC 1 and photosensitizer are immobilized together on the photoanode. The electrons efficiently transfer from the WOC to the photogenerated oxidizing photosensitizer, and a high photocurrent density of 85 µA cm(-2) is obtained by applying 0.3 V bias vs. NHE.

11.
Front Immunol ; 14: 1178691, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215136

RESUMO

Perioperative neurocognitive disorders (PND) is a common surgical anesthesia complication characterized by impairment of memory, attention, language understanding and social ability, which can lead to a decline in the quality of life of patients, prolong the hospitalization period and increase the mortality rate. PND has a high incidence rate, which has a great impact on postoperative recovery and quality of life of patients, and has caused a heavy economic burden to society and families. In recent years, PND has become an important public health problem. The high risk population of PND is more prone to gut microbiota imbalance, and gut microbiota may also affect the inflammatory response of the central nervous system through the microbiota-gut-brain axis. Meanwhile, Neuroinflammation and immune activation are important mechanisms of PND. Regulating gut microbiota through probiotics or fecal bacteria transplantation can significantly reduce neuroinflammation, reduce the abnormal activation of immune system and prevent the occurrence of PND. This review summarizes the research progress of gut microbiota and PND, providing basis for the prevention and treatment of PND.


Assuntos
Microbioma Gastrointestinal , Qualidade de Vida , Humanos , Doenças Neuroinflamatórias , Transtornos Neurocognitivos , Sistema Nervoso Central
12.
Front Cell Infect Microbiol ; 13: 1142041, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909735

RESUMO

Polycystic ovary syndrome (PCOS) is the most common endocrine diseases in women of childbearing age that leads to menstrual disorders and infertility. The pathogenesis of PCOS is complex and has not yet been fully clarified. Gut microbiota is associated with disorders of lipid, glucose, and steroid hormone metabolish. A large body of studies demonstrated that gut microbiota could regulate the synthesis and secretion of insulin, and affect androgen metabolism and follicle development, providing us a novel idea for unravelling the pathogenesis of PCOS. The relationship between gut microbiota and the pathogenesis of PCOS is particularly important. This study reviewed recent research advances in the roles of gut microbiota in the occurrence and development of PCOS. It is expected to provide a new direction for the treatment of PCOS based on gut microbiota.


Assuntos
Microbioma Gastrointestinal , Resistência à Insulina , Síndrome do Ovário Policístico , Feminino , Humanos , Síndrome do Ovário Policístico/tratamento farmacológico , Microbioma Gastrointestinal/fisiologia , Disbiose/complicações , Insulina
13.
Front Immunol ; 14: 1153851, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033951

RESUMO

Endometritis is a kind of common obstetric disease in women, usually caused by various pathogenic bacteria. Neutrophil infiltration is one of the most important pathological features of endometritis. Neutrophils can reach the uterine cavity through the endometrium, and make early response to the infection caused by the pathogen. Neutrophil extracellular traps (NETs), a meshwork of chromatin fibers extruded by neutrophils, have a role in entrapping microbial pathogens. It has been confirmed that NETs have a strong antibacterial effect and play crucial roles in the occurrence and development of various diseases. However, while killing pathogenic bacteria, excessive NETs formation may cause immune damage to the body. NETs are present in endometrium of female domestic animals in different physiological periods, especially post-mating, postpartum and in the presence of lesions, especially in endometritis. Meanwhile, NETs and its products might contribute to a reduction in physical clearance and persistent endometritis. In brief, NETs is a double-edged sword and it may play a different role in the development of endometritis, which may be beneficial or harmful, and its specific mechanism needs further study. Here we provide an overview of the role of NETs in the development of endometritis and the regulatory role of selenium on NETs formation and endometritis.


Assuntos
Endometrite , Armadilhas Extracelulares , Humanos , Animais , Gravidez , Feminino , Endometrite/microbiologia , Neutrófilos , Endométrio , Animais Domésticos
14.
Int Immunopharmacol ; 118: 110004, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36958214

RESUMO

Endometritis, a common gynecological disease, is the most common cause of infertility. As a natural metabolite of gut microbiota, deoxycholic acid (DCA) has been reported to have anti-inflammatory function. In the current study, the protective role of DCA on Staphylococcus aureus (S.aureus)-induced endometritis was tested. In vivo, DCA inhibited uterine histological change, MPO activity, endometrial barrier disruption, and inflammatory cytokine production induced by S.aureus. In vitro, DCA suppressed S.aureus-induced TNF-α and IL-1ß production in mouse endometrial epithelial cells (mEECs). Also, DCA markedly suppressed S.aureus-induced NF-κB activation. Takeda G protein-coupled receptor 5 (TGR5)is a critical bile acid membranereceptor that mainly regulated the cyclic AMP (cAMP)/protein kinase A (PKA)signaling pathway to inhibit NF-κB activation. We found DCA significantly increased TGR5 and PKA expression and S.aureus-induced inflammatory cytokine production and NF-κB activation were prevented by TGR5 inhibitor and PKA inhibitor. In conclusion, DCA protected S.aureus-induced endometritis by regulating TGR5/PKA/NF-κB signaling pathway.


Assuntos
Endometrite , Humanos , Animais , Feminino , Camundongos , Endometrite/tratamento farmacológico , Endometrite/patologia , NF-kappa B/metabolismo , Staphylococcus aureus/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Ácido Desoxicólico
15.
IEEE Trans Neural Netw Learn Syst ; 34(6): 2767-2780, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34550893

RESUMO

Trust prediction provides valuable support for decision making, information dissemination, and product promotion in online social networks. As a complex concept in the social network community, trust relationships among people can be established virtually based on: 1) their interaction behaviors, e.g., the ratings and comments that they provided; 2) the contextual information associated with their interactions, e.g., location and culture; and 3) the relative temporal features of interactions and the time periods when the trust relationships hold. Most of the existing works only focus on some aspects of trust, and there is not a comprehensive study of user trust development that considers and incorporates 1)-3) in trust prediction. In this article, we propose a context-aware deep trust prediction model C-DeepTrust to fill this gap. First, we conduct user feature modeling to obtain the user's static and dynamic preference features in each context. Static user preference features are obtained from all the ratings and reviews that a user provided, while dynamic user preference features are obtained from the items rated/reviewed by the user in time series. The obtained context-aware user features are then combined and fed into the multilayer projection structure to further mine the context-aware latent features. Finally, the context-aware trust relationships between users are calculated by their context-aware feature vector cosine similarities according to the social homophily theory, which shows a pervasive property of social networks that trust relationships are more likely to be developed among similar people. Extensive experiments conducted on two real-world datasets show the superior performance of our approach compared with the representative baseline methods.

16.
Clin Chim Acta ; 548: 117463, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37392864

RESUMO

BACKGROUND: Coagulopathy is a common complication of heart failure (HF), but the prognostic significance of coagulation abnormalities for HF is still poorly understood. This investigation sought to elucidate the association between admission prothrombin time activity (PTA) and short-term readmission in HF. METHODS: In this retrospective study, we extracted data from a publicly accessible database for hospitalized HF patients in China. The admission laboratory findings were screened by the least absolute shrinkage and selection operator (LASSO) regression. Afterward, the study population was stratified according to the admission PTA level. In univariate and multivariate analysis, we employed logistics regression model to evaluate the association of admission PTA level with short-term readmission. Subgroup analysis was preformed to examine the interaction effect between admission PTA level and covariates, including age, sex, and systolic blood pressure (SBP). RESULTS: A total of 1505 HF patients were included, of whom 58.7% were female and 35.6% were between 70 and 79 y. In LASSO procedure, admission PTA level was included in optimized models for short-term readmission, and readmitted patients tended to have a lower admission PTA level. Multivariate analysis suggested that the low admission PTA level (admission PTA ≤ 62.3%) was associated with increased risk of 90-day readmission (odds ratio 1.63 [95% CI, 1.09 to 2.46]; P = 0.02) and 180-day readmission (odds ratio 1.65 [95% CI, 1.18 to 2.33]; P = 0.01) compared with patients with the highest admission PTA level (admission PTA ≥ 76.8%) after full adjustment. Moreover, no significant interaction effect was observed in the subgroup analysis, except for admission SBP. CONCLUSION: Low admission PTA level is associated with an increased risk of 90-day and 180-day hospital readmission in patients with HF.


Assuntos
Insuficiência Cardíaca , Readmissão do Paciente , Humanos , Feminino , Masculino , Estudos Retrospectivos , Tempo de Protrombina , Fatores de Risco
17.
ACS Omega ; 5(26): 16183-16188, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32656440

RESUMO

A facile in situ one-step route for the preparation of platinum nanoparticles supported on metal-organic frameworks (MOFs) without adding stabilizing agents was developed. The obtained 10% Pt@MOF-T3 material possessed a large surface area and high crystallinity. Meanwhile, uniform and well-dispersed platinum nanoparticles were formed inside the cavities of MOFs, which could be attributed to the efficient complexation and stabilization effect derived from the dipyridyl groups. The as-synthesized 10% Pt@MOF-T3 sample showed high activity and selectivity in the hydrogenation of 5-hydroxymethylfurfural (HMF). This excellent catalytic performance could be attributed to the synergistic effects of well-dispersed platinum nanoparticles and electron donation offered by MOFs. Meanwhile, the presence of bipyridine ligands in the MOF framework avoided the irreversible adsorption of the hydrocarbon compounds, leading to the enhanced catalytic efficiency. Besides, it was easily recycled and reused at least five times, showing good recyclability.

18.
Biomed Res Int ; 2018: 2898546, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30584532

RESUMO

BACKGROUND: The metabolic energy expenditure (MEE) was the most important assessment standard of intelligent prosthetic knee (IPK). Maximum swing flexion (MSF) angle and gait symmetry (GS) were two control targets representing different developing directions for IPK. However, the few comparisons based on MEE assessment between the MSF and GS limited the development of the IPK design. OBJECTIVES: The aim of the present work was to find out the MEE difference of amputees using IPK with control targets of MSF and GS and determine which target was more suitable for the control of IPK based on the MEE assessment. METHODS: The crossover trial was designed. Six unilateral transfemoral amputees participated in the study. The amputees were assessed when wearing the IPK with different control targets, namely, the maximum swing flexion angle and gait symmetry. The oxygen consumption analysis during walking at different speeds on a treadmill was carried out. RESULTS: All subjects showed increased oxygen consumption as walking speed increased. However, no statistically significant differences were found in oxygen consumption for different control targets. The ANOVA test showed that the overall effects of the control targets of the prosthetic knee on oxygen consumption were not significant across all walking speeds. CONCLUSIONS: The control targets of MSF and GS showed no significant differences on MEE in above-knee amputees using IPK. From perspective of amputee's metabolic costs, either maximum swing flexion or gait symmetry could be suitable control target for the IPK.


Assuntos
Amputados/reabilitação , Metabolismo Energético/fisiologia , Marcha/fisiologia , Articulação do Joelho/fisiologia , Joelho/fisiologia , Adulto , Membros Artificiais , Fenômenos Biomecânicos/fisiologia , Estudos Cross-Over , Teste de Esforço/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Desenho de Prótese/métodos , Amplitude de Movimento Articular/fisiologia , Caminhada/fisiologia , Adulto Jovem
19.
Technol Health Care ; 26(1): 133-144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29060946

RESUMO

BACKGROUND: Prosthetic knee is the most important component of lower limb prosthesis. Speed adaptive for prosthetic knee during swing flexion is the key method to realize physiological gait. OBJECTIVE: This study aims to discuss the target of physiological gait, propose a speed adaptive control method during swing flexion and research the damping adjustment law of intelligent hydraulic prosthetic knee. METHODS: According to the physiological gait trials of healthy people, the control target during swing flexion is defined. A new prosthetic knee with fuzzy logical control during swing flexion is designed to realize the damping adjustment automatically. The function simulation and evaluation system of intelligent knee prosthesis is provided. Speed adaptive control test of the intelligent prosthetic knee in different velocities are researched. RESULTS: The maximum swing flexion of the knee angle is set between sixty degree and seventy degree as the target of physiological gait. Preliminary experimental results demonstrate that the prosthetic knee with fuzzy logical control is able to realize physiological gait under different speeds. The faster the walking, the bigger the valve closure percentage of the hydraulic prosthetic knee. CONCLUSIONS: The proposed fuzzy logical control strategy and intelligent hydraulic prosthetic knee are effective for the amputee to achieve physiological gait.


Assuntos
Marcha/fisiologia , Prótese do Joelho , Amplitude de Movimento Articular/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Lógica Fuzzy , Humanos , Masculino , Desenho de Prótese , Velocidade de Caminhada , Adulto Jovem
20.
Technol Health Care ; 26(4): 581-592, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710741

RESUMO

BACKGROUND: The microprocessor-controlled prosthetic knees have been introduced to transfemoral amputees due to advances in biomedical engineering. A body of scientific literature has shown that the microprocessor-controlled prosthetic knees improve the gait and functional abilities of persons with transfemoral amputation. OBJECTIVE: The aim of this study was to propose a new microprocessor-controlled prosthetic knee (MPK) and compare it with non-microprocessor-controlled prosthetic knees (NMPKs) under different walking speeds. METHODS: The microprocessor-controlled prosthetic knee (i-KNEE) with hydraulic damper was developed. The comfortable self-selected walking speeds of 12 subjects with i-KNEE and NMPK were obtained. The maximum swing flexion knee angle and gait symmetry were compared in i-KNEE and NMPK condition. RESULTS: The comfortable self-selected walking speeds of some subjects were higher with i-KNEE while some were not. There was no significant difference in comfortable self-selected walking speed between the i-KNEE and the NMPK condition (P= 0.138). The peak prosthetic knee flexion during swing in the i-KNEE condition was between sixty and seventy degree under any walking speed. In the NMPK condition, the maximum swing flexion knee angle changed significantly. And it increased with walking speed. There is no significant difference in knee kinematic symmetry when the subjects wear the i-KNEE or NMPK. CONCLUSIONS: The results of this study indicated that the new microprocessor-controlled prosthetic knee was suitable for transfemoral amputees. The maximum swing flexion knee angle under different walking speeds showed different properties in the NMPK and i-KNEE condition. The i-KNEE was more adaptive to speed changes. There was little difference of comfortable self-selected walking speed between i-KNEE and NMPK condition.


Assuntos
Amputados , Prótese do Joelho , Microcomputadores , Desenho de Prótese , Velocidade de Caminhada , Adulto , Membros Artificiais , Fenômenos Biomecânicos , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Amplitude de Movimento Articular
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