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1.
EMBO J ; 42(9): e111762, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36943004

RESUMO

Senescence and altered differentiation potential of bone marrow stromal cells (BMSCs) lead to age-related bone loss. As an important posttranscriptional regulatory pathway, alternative splicing (AS) regulates the diversity of gene expression and has been linked to induction of cellular senescence. However, the role of splicing factors in BMSCs during aging remains poorly defined. Herein, we found that the expression of the splicing factor Y-box binding protein 1 (YBX1) in BMSCs decreased with aging in mice and humans. YBX1 deficiency resulted in mis-splicing in genes linked to BMSC osteogenic differentiation and senescence, such as Fn1, Nrp2, Sirt2, Sp7, and Spp1, thus contributing to BMSC senescence and differentiation shift during aging. Deletion of Ybx1 in BMSCs accelerated bone loss in mice, while its overexpression stimulated bone formation. Finally, we identified a small compound, sciadopitysin, which attenuated the degradation of YBX1 and bone loss in old mice. Our study demonstrated that YBX1 governs cell fate of BMSCs via fine control of RNA splicing and provides a potential therapeutic target for age-related osteoporosis.


Assuntos
Células-Tronco Mesenquimais , Osteoporose , Humanos , Camundongos , Animais , Osteogênese/genética , Envelhecimento/metabolismo , Senescência Celular , Diferenciação Celular/genética , Osteoporose/metabolismo , Células da Medula Óssea , Proteína 1 de Ligação a Y-Box/metabolismo
2.
Nat Mater ; 22(10): 1253-1260, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37604908

RESUMO

Hydrogel materials show promise for diverse applications, particular as biocompatible materials due to their high water content. Despite advances in hydrogel technology in recent years, their application is often severely limited by inadequate mechanical properties and time-consuming fabrication processes. Here we report a rapid hydrogel preparation strategy that achieves the simultaneous photo-crosslinking and establishment of biomimetic soft-hard material interface microstructures. These biomimetic interfacial-bonding nanocomposite hydrogels are prepared within seconds and feature clearly separated phases but have a strongly bonded interface. Due to effective interphase load transfer, biomimetic interfacial-bonding nanocomposite gels achieve an ultrahigh toughness (138 MJ m-3) and exceptional tensile strength (15.31 MPa) while maintaining a structural stability that rivals or surpasses that of commonly used elastomer (non-hydrated) materials. Biomimetic interfacial-bonding nanocomposite gels can be fabricated into arbitrarily complex structures via three-dimensional printing with micrometre-level precision. Overall, this work presents a generalizable preparation strategy for hydrogel materials and acrylic elastomers that will foster potential advances in soft materials.

3.
BMC Musculoskelet Disord ; 25(1): 191, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431558

RESUMO

BACKGROUND: Plantar fasciitis (PF) is the most common cause of heel pain. Among conservative treatments, extracorporeal shock wave therapy (ESWT) is considered effective for refractory PF. Studies have shown that applying ESWT to the trigger points (TrPs) in the triceps surae may play an important role in pain treatment in patients with PF. Therefore, the purpose of this study was to combine the concept of trigger points and ESWT to explore the effect of this combination on plantar temperature and pressure in patients with PF. METHODS: After applying inclusion and exclusion criteria, 86 patients with PF were recruited from the pain clinic of Huadong Hospital, Fudan University and randomly divided into experimental (n = 43) and control groups (n = 43). The experimental group was treated with extracorporeal shock waves to treat the medial heel pain point and the gastrocnemius and soleus TrPs. The control group was only treated with extracorporeal shock waves at the medial heel pain point. The two groups were treated twice with an interval of 1 week. Primary measurements included a numerical rating scale (NRS) score (overall, first step, heel pain during daily activities), and secondary measurements included heel temperature, Roles-Maudsley score (RMS), and plantar pressure. All assessments were performed before treatment (i.e., baseline) and 6 and 12 weeks after treatment. RESULTS: During the trial, 3 patients in the experimental group withdrew from the study, 2 due to interruption of the course of treatment by the COVID-19 epidemic and 1 due to personal reasons. In the control group, 3 patients fell and were removed due to swelling of the heel. Therefore, only 80 patients with PF were finally included. After treatment, the two groups showed good results in NRS score (overall, first step, heel pain during daily activities), RMS, and plantar temperature, especially in the experimental group, who showed a significantly better effect than the control group. CONCLUSION: ESWT of the heel combined with the triceps trigger point of the calf can more effectively improve the pain, function and quality of life of refractory PF than ESWT of the heel alone. In addition, ESWT of the heel combined with the triceps trigger point of the calf can effectively reduce the skin temperature of the heel on the symptomatic side, indicating that the heel temperature as measured by infrared thermal imaging may be used as an independent tool to evaluate the therapeutic effect for patients with chronic PF. Although extracorporeal shock waves combined with TrPs treatment can cause changes in the patients' gait structure, plantar pressure is still difficult to use as an independent tool to evaluate the therapeutic effect for PF. TRIAL REGISTRATION: Registered in the Chinese Clinical Trial Registry ( www.chictr.org.cn ) on 12/17/2021 with the following code: ChiCTR-INR-2,100,054,439.


Assuntos
Fasciíte Plantar , Humanos , Fasciíte Plantar/complicações , Calcanhar , Pontos-Gatilho , Qualidade de Vida , Temperatura , Resultado do Tratamento , Dor/etiologia
4.
Molecules ; 29(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38611837

RESUMO

Silver (Ag) nanowires, as an important one-dimensional (1D) nanomaterial, have garnered wide attention, owing to their applications in electronics, optoelectronics, sensors, and other fields. In this study, an alternative hydrothermal route was developed to synthesize Ag nanowires via modified reduction of Ag+. Silver sulfamate plays an important role in the formation of Ag nanowires via controlled release of free Ag+. Results of controlled experiments and characterizations such as UV-vis spectroscopy, FTIR, XPS, and 1H NMR revealed that sulfamic acid does not function as a reductant, supporting by the generation of free Ag+ instead of Ag nanostructures in hydrothermally treated silver sulfamate solution. The initial reduction of Ag+ was induced by the combination of poly (vinylpyrrolidone) (PVP) end group and degradation products. This phenomenon was supported by abundant free Ag+ in the mixed preheated silver sulfamatic and preheated PVP aqueous solutions, indicating a second and distinct Ag+ autocatalytic reduction. Thus, the roles of different reagents and Ag+ reduction must be studied for nanomaterial syntheses.

5.
BMC Musculoskelet Disord ; 24(1): 36, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36650486

RESUMO

BACKGROUND: Latent and active myofascial trigger points (MTrPs) in knee-associated muscles may play a key role in pain management among patients with knee osteoarthritis (KOA). The aim of this study was to investigate the effect of dry needling treatment on pain intensity, disability, and range of motion (ROM) in patients with KOA. METHODS: This randomized, single-blinded, clinical trial was carried out for 6 weeks of treatment and 6-month follow-up. A total of 98 patients met the entry criteria and were randomly assigned to the dry needling latent and active myofascial trigger point (MTrPs) with the stretching group or the oral diclofenacwith the stretching group. Numeric Pain Rating Scale (NPRS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and ROM were statistically analyzed before and after treatment and at the 6-month follow-up. RESULTS: A total of 42 patients in the dry needling group (DNG) and 35 patients in the diclofenac group (DG), respectively, completed the study, and there was no significant difference in the general data between the two groups. After treatments, both the groups showed a good effect in knee pain, function, and ROM, However, the DNG showed a significantly better result than the DG. Especially in the results of the 6-month follow-up, the DNG showed much better results than the DG. CONCLUSIONS: Dry needling on latent and active MTrPs combined with stretching and oral diclofenac combined with stretching can effectively relieve pain, improve function, and restore knee ROM affected by KOA. However, the effects of dry needling and stretching are better and longer lasting than those of oral diclofenac and stretching for at least 6 months. TRIAL REGISTRATION: Registered in the Chinese Clinical Trial Registry ( www.chictr.org.cn ) in 17/11/2017 with the following code: ChiCTR-INR-17013432.


Assuntos
Agulhamento Seco , Síndromes da Dor Miofascial , Osteoartrite do Joelho , Humanos , Pontos-Gatilho , Diclofenaco/uso terapêutico , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/tratamento farmacológico , Dor , Síndromes da Dor Miofascial/tratamento farmacológico
6.
Anal Chem ; 94(7): 3296-3302, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35143169

RESUMO

Due to near-zero optical background and photobleaching, electrochemiluminescence (ECL), an optical phenomenon excited by electrochemical reactions, has drawn extensive attention, especially for ultrasensitive bioassays. Developing diverse ECL emitters is crucial to unlocking their multiformity and performances but remains a formidable challenge due to the rigorous requirements for ECL. Herein, we report a general strategy to light up ECL-inactive dyes in an aqueous solution via grafting, a well-developed concept for plant propagation since 500 BCE. As a proof of concept, a series of luminol donor-dye acceptor-based ECL emitters were grafted with near-unity resonance energy transfer (RET) efficiency and coarse/fine-tunable emission wavelengths. Rather than the sophisticated design of new skeleton-based molecules to meet all of the prerequisites for ECL in a constrained manner, each unit in the proposed ECL ensemble performed its functions maximally. As a result, beyond traditional two-dimensional (2D) ones, a three-dimensional (3D) coordinate biosensing system, simultaneously showing a calibration curve and selectivity, was established using the new ECL emitter. This lighting up strategy would generally address the scarcity of ECL emitters and enable unprecedented functions.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Técnicas Biossensoriais/métodos , Corantes , Técnicas Eletroquímicas/métodos , Transferência de Energia , Medições Luminescentes/métodos
7.
Anal Chem ; 94(47): 16510-16518, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36374940

RESUMO

Tuning the electrochemiluminescence (ECL) wavelength of carbon dots (CDs) with enhanced efficiency is essential for multiplexed biosensing, bioimaging, and energy applications but remains challenging. Herein, we reported a facile route to finely modulate the ECL wavelength of CDs from 425 to 645 nm, the widest range ever reported, along with a more than 5-fold enhancement of ECL efficiency via phosphorous (P) incorporation. The molecular mechanism was explored experimentally and theoretically, which revealed the unusual dual roles of P dopants in the form of P-C and P-O bonding, that is, importing shallow trapping states and promoting an effective intramolecular charge transfer. This work would allow unlocking the key factors of ECL kinetics for heteroatom-doped CDs appearing out of reach and open a new avenue for the rational design of nanocarbon for desirable applications.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Carbono , Medições Luminescentes/métodos , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos
8.
Cell Biol Int ; 46(5): 755-770, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35077602

RESUMO

Human amniotic epithelial cells (hAECs), one of the stem cells identified from the human placenta, possess numerous advantages and have been considered as an attractive and available cell source for regenerative medicine. Accumulating evidence has showed that cellular senescence was one of the pathogenic hubs of diabetic wound chronicity. Keratinocytes and fibroblasts are the primary cells involved in wound healing. Therefore, in this study, we aimed to investigate the anti-senescence effects of hAECs on keratinocytes and fibroblasts in diabetic wounds. Sustained hyperglycemia impaired cell function and accelerated senescence in vitro. However, this phenotype was rescued by hAECs-conditioned medium (hAECs-CM), with increased migration and proliferation in keratinocytes and fibroblasts and enhanced collagen synthesis and α-smooth muscle actin (α-SMA) production in fibroblasts. In addition, hAECs-CM dramatically inhibited intracellular reactive oxygen species (ROS) and senescence-associated ß-galactosidase (SA-ß-gal) in keratinocytes and fibroblasts under high-glucose (HG) condition. Moreover, hAECs-CM could downregulate the increased RAGE and P21 induced by continuous HG stimulation. Intradermal injection of hAECs in diabetic wounds promoted re-epithelialization and granulation tissue formation, accompanied by decreased P21+ cells and increased PCNA+ cells in epidermis and dermis, as well as promoted collagen deposition and α-SMA expression. Furthermore, CM-Dil-labeled hAECs survived to Day 5 but disappeared by Day 10 in diabetic wounds. These findings indicated that hAECs could inhibit diabetes-induced premature senescence and enhance the function of keratinocytes and fibroblasts via paracrine effects, partly by inhibiting RAGE/P21 signaling pathway. Thus, hAECs targeting cellular senescence induced by a hyperglycemic environment may be a new strategy for the treatment of diabetic wounds.


Assuntos
Diabetes Mellitus , Queratinócitos , Células Cultivadas , Diabetes Mellitus/metabolismo , Fibroblastos/metabolismo , Glucose/metabolismo , Glucose/farmacologia , Humanos , Queratinócitos/metabolismo , Cicatrização
9.
J Nanobiotechnology ; 20(1): 304, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761332

RESUMO

Muscle atrophy is a frequently observed complication, characterized by the loss of muscle mass and strength, which diminishes the quality of life and survival. No effective therapy except exercise is currently available. In our previous study, repressing miR-29b has been shown to reduce muscle atrophy. In our current study, we have constructed artificially engineered extracellular vesicles for the delivery of CRISPR/Cas9 to target miR-29b (EVs-Cas9-29b). EVs-Cas9-29b has shown a favorable functional effect with respect to miR-29b repression in a specific and rapid manner by gene editing. In in vitro conditions, EVs-Cas9-29b could protect against muscle atrophy induced by dexamethasone (Dex), angiotensin II (AngII), and tumor necrosis factor-alpha (TNF-α). And EVs-Cas9-29b introduced in vivo preserved muscle function in the well-established immobilization and denervation-induced muscle atrophy mice model. Our work demonstrates an engineered extracellular vesicles delivery of the miR-29b editing system, which could be potentially used for muscle atrophy therapy.


Assuntos
Vesículas Extracelulares , MicroRNAs , Atrofia Muscular , Animais , Sistemas CRISPR-Cas , Camundongos , MicroRNAs/genética , Atrofia Muscular/genética , Atrofia Muscular/terapia , Fator de Necrose Tumoral alfa
10.
Anal Chem ; 93(25): 8971-8977, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34138530

RESUMO

The development of electrochemiluminescent (ECL) emitters with both intense ECL and excellent film-forming properties is highly desirable for biosensing applications. Herein, a facile one-pot preparation strategy was proposed for the synthesis of a self-enhanced ECL emitter by co-doping Ru(bpy)32+ and (diethylaminomethyl)triethoxysilane (DEAMTES) into an in situ-produced silica nanohybrid (DEAMTES@RuSiO2). DEAMTES@RuSiO2 not only possessed improved ECL properties but also exhibited outstanding film-forming ability, which are both critical for the construction of ECL biosensors. By coupling branched catalytic hairpin assembly with efficient signal amplification peculiarity, a label-free ECL biosensor was further constructed for the convenient and highly sensitive detection of miRNA-21. The as-fabricated ECL biosensor displayed a detection limit of 8.19 fM, much lower than those in previous reports for miRNA-21 and showed superior reliability for detecting miRNA-21-spiked human serum sample, demonstrating its potential for applications in miRNA-associated fundamental research and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Técnicas Eletroquímicas , Humanos , Medições Luminescentes , Reprodutibilidade dos Testes
11.
Pain Pract ; 21(2): 160-170, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32700432

RESUMO

OBJECTIVES: To compare the long-term efficacy between pulsed radiofrequency (PRF) combined with passive stretching (PRF-PS) exercise and PS exercise alone in reducing pain and improving quadriceps muscle strength and knee function. METHODS: Sixty-two participants were randomly assigned with a 1:1 allocation to the PRF-PS exercise group or the PS exercise group. Level of pain, muscle strength, and knee function were assessed from baseline to the first, third, and sixth months after treatment using the VAS, peak torque (PT), and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), respectively. RESULTS: There were no significant differences at baseline between the 2 groups. Compared to exercise alone, participants achieved superior efficacy with PRF-PS in pain relief, improvement of muscle strength, and knee function. Moreover, the improvement of all variables was maintained for a longer period of time in the PRF-PS group. The reduction in participants' VAS pain intensity scores was superior for PRF-PS vs. PS with overall estimation (adjusted mean difference: -1.85 cm; 95% confidence interval [CI] -2.25, -1.45 cm; P = 0.000). The increase in participants' PT scores was superior for PRF-PS vs. PS with overall estimation (adjusted mean difference: 15.53 N. m; 95% CI 7.07, 23.98 N. m; P = 0.000; and 12.62 N. m; 95% CI 0.96, 24.28 N. m; P = 0.000 for PT 60 degrees/s and PT 180 degrees/s, respectively). The reduction in participants' WOMAC scores was superior for PRF-PS vs. PS with overall estimation (adjusted mean difference: -16.43; 95% CI -22.22, -10.64; P = 0.000). DISCUSSION: The improvement in pain relief and knee function might be associated with restoration of muscle strength after PRF-PS exercise by overcoming muscle inhibition.


Assuntos
Terapia por Exercício/métodos , Osteoartrite do Joelho/reabilitação , Tratamento por Radiofrequência Pulsada/métodos , Recuperação de Função Fisiológica , Adolescente , Adulto , Idoso , Feminino , Humanos , Articulação do Joelho , Masculino , Pessoa de Meia-Idade , Manejo da Dor/métodos , Projetos Piloto , Adulto Jovem
12.
Angew Chem Int Ed Engl ; 59(34): 14498-14503, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32515070

RESUMO

Emerging as a cost-effective and robust enzyme mimic, nanozymes have drawn increasing attention with broad applications ranging from cancer therapy to biosensing. Developing nanozymes with both accelerated and inhibited biocatalytic properties in a biological context is intriguing to peruse more advanced functions of natural enzymes, but remains challenging, because most nanozymes are lack of enzyme-like molecular structures. By re-visiting and engineering the well-known Fe-N-C electrocatalyst that has a heme-like Fe-Nx active sites, herein, it is reported that Fe-N-C could not only catalyze drug metabolization but also had inhibition behaviors similar to cytochrome P450 (CYP), endowing it a potential replacement of CYP for preliminary evaluation of massive potential chemicals, drug dosing guide, and outcome prediction. In addition, in contrast to electrocatalysts, the highly graphitic framework of Fe-N-C may not be obligatory for a competitive CYP-like activity.


Assuntos
Carbono/metabolismo , Interações Medicamentosas , Enzimas/metabolismo , Ferro/metabolismo , Nanoestruturas/química , Nitrogênio/metabolismo , Biocatálise , Domínio Catalítico , Microscopia Eletrônica/métodos , Análise Espectral/métodos
13.
Angew Chem Int Ed Engl ; 59(38): 16747-16754, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32524717

RESUMO

The exceptional nature of WO3-x dots has inspired widespread interest, but it is still a significant challenge to synthesize high-quality WO3-x dots without using unstable reactants, expensive equipment, and complex synthetic processes. Herein, the synthesis of ligand-free WO3-x dots is reported that are highly dispersible and rich in oxygen vacancies by a simple but straightforward exfoliation of bulk WS2 and a mild follow-up chemical conversion. Surprisingly, the WO3-x dots emerged as co-reactants for the electrochemiluminescence (ECL) of Ru(bpy)32+ with a comparable ECL efficiency to the well-known Ru(bpy)32+ /tripropylamine (TPrA) system. Moreover, compared to TPrA, whose toxicity remains a critical issue of concern, the WO3-x dots were ca. 300-fold less toxic. The potency of WO3-x dots was further explored in the detection of circulating tumor cells (CTCs) with the most competitive limit of detection so far.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Células Neoplásicas Circulantes/patologia , Compostos Organometálicos/química , Óxidos/química , Propilaminas/química , Tungstênio/química , Humanos , Óxidos/síntese química
14.
Sensors (Basel) ; 19(14)2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31330918

RESUMO

Mobile laser scanning (MLS) is widely used in the mapping of forest environments. It has become important for extracting the parameters of forest trees using the generated environmental map. In this study, a three-dimensional point cloud map of a forest area was generated by using the Velodyne VLP-16 LiDAR system, so as to extract the diameter at breast height (DBH) of individual trees. The Velodyne VLP-16 LiDAR system and inertial measurement units (IMU) were used to construct a mobile measurement platform for generating 3D point cloud maps for forest areas. The 3D point cloud map in the forest area was processed offline, and the ground point cloud was removed by the random sample consensus (RANSAC) algorithm. The trees in the experimental area were segmented by the European clustering algorithm, and the DBH component of the tree point cloud was extracted and projected onto a 2D plane, fitting the DBH of the trees using the RANSAC algorithm in the plane. A three-dimensional point cloud map of 71 trees was generated in the experimental area, and estimated the DBH. The mean and variance of the absolute error were 0.43 cm and 0.50, respectively. The relative error of the whole was 2.27%, the corresponding variance was 15.09, and the root mean square error (RMSE) was 0.70 cm. The experimental results were good and met the requirements of forestry mapping, and the application value and significance were presented.

15.
Anal Bioanal Chem ; 410(24): 6197-6205, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30006725

RESUMO

A sensitive competitive immunoassay with simple operation was developed for the detection of the anti-virus drug amantadine (AMD). The single-chain variable fragment (scFv) antibody against AMD was site-specific biotinylated and overexpressed as a secreted body in Escherichia coli AVB101. Horseradish peroxidase-labeled streptavidin-biotinylated scFv antibody (HRP-SA-BIO-scFv) could specifically bind to AMD-functionalized magnetic beads (MBs) and then the immune complexes were separated from the matrix solution by magnet. The concentration of the AMD could be known by the measurement of the signal produced by the horseradish peroxidase. The newly established assay provides a significant improvement in comparison to the conventional ELISA without SA-BIO signal amplification and MBs separation. The limit of detection and assay time was 0.64 vs. 8.4 ng/mL and 50 vs. 150 min, respectively. The recoveries ranged from 77.8 to 112% with the coefficient of variation less than 13%. The immunoassay exhibited an obvious cross-reactivity to rimantadine (84%), 1-(1-adamantyl)ethylamine (72%), and somantadine (63%). These results demonstrated that the developed immunoassay provided a sensitive, rapid, and accurate approach for the detection of AMD in chicken by employing MBs as solid phase and SA-BIO as signal amplification. When applied in natural chicken samples, the newly established method provided results consistent with those from UPLC-MS/MS, suggesting that the proposed method could be used for rapid screening of the target of interest; the new immunoassay could also be extended to other small molecular contaminants and thus represents a universal strategy for food safety analysis. Graphical abstract ᅟ.


Assuntos
Amantadina/análise , Antivirais/análise , Biotina/química , Ensaio de Imunoadsorção Enzimática/métodos , Magnetismo , Anticorpos de Cadeia Única/imunologia , Amantadina/imunologia , Amantadina/uso terapêutico , Animais , Antivirais/imunologia , Antivirais/uso terapêutico , Galinhas , Cromatografia Líquida de Alta Pressão , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Influenza Aviária/tratamento farmacológico , Influenza Aviária/prevenção & controle , Limite de Detecção , Espectrometria de Massas em Tandem
16.
J Phys Chem A ; 122(26): 5750-5755, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29893562

RESUMO

The acidities of 40 commonly seen cations of ionic liquids (CILs) in dimethyl sulfoxide (DMSO) were investigated by a well-established theoretical method, SMD/M06-2X/6-311++G (2df,2p)//B3LYP/6-31+G(d). The calculated p Ka's agree excellently with the available experimental data and range from 20.0 to 45.8 with an acidity order of 1,3-dialkylimidazolium > amidinium > pyridinium > tetraalkylphosphonium > morpholinium > pyrrolidinium ≈ piperidinium > guanadinim cations. The established acidity scale in this work provides a useful tool, as verified by the acidity comparisons, to assess the stability of ILs under various extent basic conditions, and also reveals the relative basicity of several classical N-heterocyclic carbenes and olefins as well as ylides.

17.
Sensors (Basel) ; 18(9)2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150554

RESUMO

Facing the adolescents and detecting their emotional state is vital for promoting rehabilitation therapy within an E-Healthcare system. Focusing on a novel approach for a sensor-based E-Healthcare system, we propose an eye movement information-based emotion perception algorithm by collecting and analyzing electrooculography (EOG) signals and eye movement video synchronously. Specifically, we extract the time-frequency eye movement features by firstly applying the short-time Fourier transform (STFT) to raw multi-channel EOG signals. Subsequently, in order to integrate time domain eye movement features (i.e., saccade duration, fixation duration, and pupil diameter), we investigate two feature fusion strategies: feature level fusion (FLF) and decision level fusion (DLF). Recognition experiments have been also performed according to three emotional states: positive, neutral, and negative. The average accuracies are 88.64% (the FLF method) and 88.35% (the DLF with maximal rule method), respectively. Experimental results reveal that eye movement information can effectively reflect the emotional state of the adolescences, which provides a promising tool to improve the performance of the E-Healthcare system.


Assuntos
Atenção à Saúde/métodos , Emoções , Movimentos Oculares , Monitorização Fisiológica/métodos , Telemedicina/métodos , Algoritmos , Automação , Eletroculografia , Feminino , Humanos , Masculino , Adulto Jovem
18.
Anal Chem ; 88(22): 10816-10820, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27797499

RESUMO

γ-Glutamyltranspetidase (GGT) is a cell-membrane-bound enzyme which selectively catalyzes cleavage of the γ-glutamyl bond of glutathione (GSH). It has been identified to be overexpressed in a number of malignant tumor cells. Therefore, fluorescent probes for fast and selective detection of GGT activities are greatly needed. However, the majority of currently available GGT fluorescent probes based on direct conjugation of a γ-glutamyl group to a specific fluorophore generally has slow enzymatic kinetics due to bulky fluorophore too close to the enzyme's active site. Moreover, the uncaged fluorophore with a free amine group might undergo oxidation or other enzymatic transformation and resulted in a complicated time-dependent fluorescence response. Herein, we reported design of a novel fluorescent GGT probe NM-GSH (2), which incorporated a fast intramolecular transcyclization cascade for rapid detection of GGT activities after enzymatic cleavage of the γ-glutamyl group. This design strategy allows introduction of bulky 1,8-naphthalimide fluorophore with improved enzymatic kinetics and lowered detection limit. The transcyclized product 4 gives more than 200-fold fluorescence increment. The probe NM-GSH showed both good selectivity and fast detection of GGT activities with the detection limit as low as 0.21 mU/mL. In addition, the fluorescent product 4 contains no free amine group and is more stable for detection. Most importantly, cell imaging studies showed that the transcyclized product 4 was enriched in lysosomes for selectively lighting up GGT-overexpressed ovarian cancer cells (OVCAR5) but not normal cells (HUVEC), indicating NM-GSH's potentials as an imaging agent in cancer diagnosis and treatment.


Assuntos
Fluorescência , Corantes Fluorescentes/química , gama-Glutamiltransferase/análise , gama-Glutamiltransferase/metabolismo , Linhagem Celular Tumoral , Ciclização , Corantes Fluorescentes/síntese química , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Microscopia Confocal , Estrutura Molecular
19.
Chemistry ; 22(27): 9247-56, 2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27244367

RESUMO

Differentiation of biologically important thiols, such as cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) is still a challenging task. Herein, we present a novel fluorescent chemodosimeter capable of selectively detecting Cys over other biothiols including Hcy and GSH and other amino acids by a facile thiol-Michael addition/transcyclization rearrangement cascade click process. The unique transcyclization step is critical for the selectivity as a result of the kinetically favorable formation of a six-membered ring with the Cys Michael adduct. Moreover, the probe adopts a distinctive dual quenching mechanism-photoinduced electron transfer (PET) and photoinduced intramolecular charge transfer (ICT) to deliver a drastic turn-on fluorescence response only at the Cys-selective transcylization step. The judicious selection of strong electron-withdrawing naphthalimide fluorophore with maleimide group enhances the electrophilicity and thus reactivity for the cascade process leading to fast detection and ultrasensitivity with a detection limit of 2.0 nm (S/N=3). The probe has demonstrated its practical utility potential in Cys imaging in live cells.


Assuntos
Cisteína/química , Corantes Fluorescentes/química , Química Click , Ciclização , Cisteína/análise , Transporte de Elétrons , Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Glutationa/química , Células HeLa , Homocisteína/química , Humanos , Limite de Detecção , Maleimidas/química , Microscopia de Fluorescência , Teoria Quântica , Espectrometria de Fluorescência
20.
Health Qual Life Outcomes ; 14: 21, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26879341

RESUMO

BACKGROUND: This study sought to statistically map the neck disability index (NDI) to the six-dimension health state short form (SF-6D) to estimate algorithms for use in economic analyses in patients with chronic neck pain (CNP). METHODS: The relationships between NDI and SF-6D scores were estimated by using data from a cohort of patients with chronic neck pain (n = 272). By using ordinary least squares (OLS), generalized linear modeling (GLM), censored least absolute deviations (CLAD) and Tobit regression, scores from all 10 items of the NDI instruments were univariately tested against SF-6D values and retained in a multivariate regression model, if statistically significant. The predictive ability of the model was assessed by mean absolute error (MAE), root mean square error (RMSE) and normalized RMSE. RESULTS: The mean age of the 272 CNP patients was 39.9 ± 12.3 years; 57.8 % of the CNP patients were female. An OLS regression equation that included recreation item of NDI was optimal, with a MAE of 0.04and 0.04 and an RMSE of 0.06and 0.05in the derivation set and validation set, respectively. Predicted utilities accurately represented the observed ones. CONCLUSIONS: We have provided algorithms for the estimation of health state utility values from the response of NDI. Future economic evaluations of the interventions for chronic neck pain could be informed by these algorithms.


Assuntos
Doença Crônica/psicologia , Avaliação da Deficiência , Cervicalgia/fisiopatologia , Cervicalgia/psicologia , Qualidade de Vida , Adulto , Algoritmos , Estudos de Coortes , Feminino , Humanos , Análise dos Mínimos Quadrados , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Inquéritos e Questionários
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