Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 919
Filtrar
1.
Zhen Ci Yan Jiu ; 45(1): 57-61, 2020 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-32144910

RESUMO

OBJECTIVE: The present study is to investigate the characteristic distribution of primary pain points and referred pain areas in patients with knee-joint pain diseases, therefore revealing the correlation between the myofascial trigger point and acupoint sensitization. METHODS: A total of 483 patients (320 men and 163 women, 36 to 72 years in age) with knee-joint pain recruited from 4 clinical centers were observed from July, 2017 to April, 2019 in the present study. The areas of primary and referred pain in these patients were detected by thumb-pressing and marked on human anatomic atlas. RESULTS: Of the 483 enrolled participants, 336 had lesion sites or tender points around the injured knee joint, and 147 with myofascial pain syndrome showed referred pain spots (zones) in the knee joint area. In 105 patients with patellar tendonitis, epiphysitis of the tibial tubero-sity, or quadriceps tendonitis, the pain area was mainly distributed in the anterior region of the knee. In 76 patients with medial collateral ligament injury, medial meniscal lesion, goose foot bursitis or semimembranosus ending-point inflammation, the pain points mainly occurred in the medial area of the knee. In 127 patients with lateral collateral ligament, lateral meniscus lesion, iliotibial band tendonitis, popliteus or triceps tendinitis, the pain spots were found in the lateral region of the knee. In 28 patients with posterior cruciate ligament injury or popliteal fossa tendonitis, the local pain was found to be at the back of the knee. Referred pain areas were normally detected in the lateral femoral muscles (43 cases), anterior femoral muscles (39 cases), adductor group of femur (26 cases), posterior popliteal fossa muscles group (15 cases), hamstrings (13 cases) and medial leg (11 cases).. CONCLUSION: The primary pain areas or spots of the knee injury mainly distribute around the joint, whereas those of each muscle group lesion are often located in their respective skeletal muscle. Most of the referred pain areas often occur in the distal end of skeletal muscle and around the knee joint. Primary myofascial trigger points may be considered to be an indicator of acupoint sensitization.


Assuntos
Pontos de Acupuntura , Pontos-Gatilho , Adulto , Idoso , Feminino , Fêmur , Humanos , Articulação do Joelho , Masculino , Pessoa de Meia-Idade , Tíbia
2.
Nanoscale Horiz ; 5(3): 523-529, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32118213

RESUMO

Super-resolution imaging technology has been a powerful tool for revealing fine biological structures and functions. Its high-quality imaging always needs highly accurate labeling. Here, by exploiting the high specificity and affinity of natural substrates to transporters, we developed one set of substrate-based small molecule fluorescent probes for labeling membrane transporters. A glucose-based probe (Glu-probe) and tyrosine-based probe (Tyr-probe) were synthesized as two examples. Confocal imaging showed that the Glu-probe could label glucose transporters on live cells by being stuck into the binding site. Compared with antibody-probe labeling, the labeling advantages of the Glu-probe were revealed. High specificity of the Glu-probe or Tyr-probe was examined by a colocalization experiment and glucose replacement or amino acid (AA) blocking. The synthetic probes were also tested on imaging HeLa cells to confirm their wide labeling application. Additionally, we found that membrane transporters were mostly in the clustered state on cellular membranes, changing their assembly pattern to regulate the transport effectiveness. These results suggest that the substrate-based probes can serve as valuable tools for investigating the spatial information of membrane transporters.

3.
Science ; 367(6484): 1352-1358, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32193323

RESUMO

We report the profiling of spatial and energetic distributions of trap states in metal halide perovskite single-crystalline and polycrystalline solar cells. The trap densities in single crystals varied by five orders of magnitude, with a lowest value of 2 × 1011 per cubic centimeter and most of the deep traps located at crystal surfaces. The charge trap densities of all depths of the interfaces of the polycrystalline films were one to two orders of magnitude greater than that of the film interior, and the trap density at the film interior was still two to three orders of magnitude greater than that in high-quality single crystals. Suprisingly, after surface passivation, most deep traps were detected near the interface of perovskites and hole transport layers, where a large density of nanocrystals were embedded, limiting the efficiency of solar cells.

4.
J Diabetes Res ; 2020: 2789209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215270

RESUMO

Objective: To evaluate the role of CCAAT/enhancer-binding protein ß (C/EBP ß (C/EBP. Methods: Rats with OIR were exposed to alternating hypoxic and hyperopic conditions for 14 days. Then, the rats with OIR were assigned randomly to groups that received intravitreal injections of either shRNA lentiviral particles targeting C/EBP ß (C/EBP ß (C/EBP ß (C/EBP ß (C/EBP ß (C/EBP ß (C/EBP. Results: In OIR rats, the expression levels of C/EBP ß (C/EBP P < 0.01). The p-C/EBP ß (C/EBP ß (C/EBP ß (C/EBP ß (C/EBP ß (C/EBP P < 0.01). The p-C/EBP ß (C/EBP ß (C/EBP ß (C/EBP P < 0.01). The p-C/EBP. Conclusions: C/EBP ß shRNA inhibits RNV in OIR. A potential mechanism may be that the activity of C/EBP ß increases with its overexpression, which in turn aggravates the amount of the retinal vascular damage and promotes transcription of VEGF. C/EBP ß might be a new therapeutic target for preventing RNV.ß (C/EBP ß (C/EBP ß (C/EBP.

5.
J Phys Chem Lett ; : 2896-2901, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32212664

RESUMO

Transition-metal-nitrogen/carbon (TM-N/C) materials are promising alternatives to Pt-based oxygen reduction reaction (ORR) electrocatalysts of fuel cells. Identifying the highly active sites is the prerequisite for the design of high-performance electrocatalysts, in which the density functional theory (DFT) calculation is an important tool. However, the DFT simulation was usually conducted with a charge-neutral model, which is far away from the working condition, that is, under certain potentials. Herein, by using the DFT method with the explicit consideration of electrode potential, we systematically compared the activities of the Fe-N/C moieties previously proposed in the literature and identified the best one. This study not only demonstrates the significance of the electrode potential in computational electrochemistry but also suggests a feasible experimental strategy to increase the ORR performance of Fe-N/C electrocatalysts by creating edges defects and coordinating with the axial ligands on the Fe center, which is of practical significance for exploring the advanced non-precious-metal-based ORR electrocatalysts and related devices.

6.
Acta Biomater ; 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32165194

RESUMO

In recent years, Zn-based materials provide a new option as biodegradable metals for orthopedic applications. To improve the low strength and brittle nature of pure Zn, small amounts of alloying element Mn (0.1, 0.4 and 0.8 wt.%) were added into Zn to fabricate binary Zn-Mn alloys. An extremely high elongation (83.96 ± 2.36%) was achieved in the resulting Zn-0.8 wt.%Mn alloy. Moreover, Zn-Mn alloys displayed significantly improved cytocompatibility as compared to pure Zn, according to cell proliferation and morphology analyses. More importantly, a significantly improved osteogenic activity was verified after adding Mn regarding ALP activity and osteogenic expression. Furthermore, Zn-0.8 wt.%Mn alloy scaffolds were implanted into the rat femoral condyle for repairing bone defects with pure Ti as control. Enhanced osteogenic activities were confirmed for Zn-0.8Mn alloy in contrast to pure Ti based on Micro-CT and histological results, and favorable in vivo biosafety of Zn-0.8Mn alloy was verified by H&E staining and blood tests. The exceptional mechanical performance and favorable osteogenic capability render Zn-Mn alloy a promising candidate material in the treatment of bone defects or fracture repair. STATEMENT OF SIGNIFICANCE: The element Mn, on the one hand, as an essential trace element in the human body, promotes cell proliferation, adhesion, spreading, and regulates bone metabolism; on the other hand, it could significantly improve the ductility of Zn alloys. Here, we systematically reported the biocompatibility and biofunctionality of binary biodegradable Zn-Mn alloys in the bone environment. The Zn-Mn alloys promoted MC3T3-E1 cell proliferation, adhesion, spreading, and osteogenic differentiation in vitro. Furthermore, a rat femoral condyle defect model was established; porous Zn-Mn alloy scaffolds were manufactured to repair the bone defects. Significant bone regenerations, considerable bone ingrowth, and desirable biosafety were confirmed in vivo. Therefore, biodegradable Zn-Mn with promising osteogenic properties may become new options for orthopedic implant materials.

7.
Cell Signal ; : 109606, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32199935

RESUMO

The proliferation of fibroblasts creates an environment favoring post-operative tendon adhesion, but targeted therapy of this pathology remains in its infancy. In this study, we explored the effect of heat shock protein 72 (HSP72), a major inducible member of the heat shock protein family that can protect cells against many cellular stresses including heat shock, on fibroblast proliferation in tendon adhesion, with its underlying mechanisms investigated. HSP72 expression was examined in an established rat model of tendon injury using RT-qPCR and immunoblot analysis. After conducting ectopic expression and depletion experiments in fibroblast NIH3T3 cells, we determined the effects of HSP72 on the expression of α-SMA and STAT3 signaling pathway-related genes, fibroblast proliferation, as well as collagen production. The mRNA (65.46%) and protein (63.65%) expression of HSP72 was downregulated in the rat model of tendon injury. The in vitro experiments revealed that overexpression of HSP72 inhibited fibroblast proliferation (42.57%) and collagen production (45.60%), as well as reducing α-SMA expression (42.49%) and the extent of STAT3 phosphorylation (55.46%). Moreover, we observed that HSP72 overexpression reduced inflammation as well as the number of inflammatory cell infiltration and fibroblasts in vivo. Furthermore, the inhibited extent of STAT3 phosphorylation contributed to the impaired fibroblast proliferation and collagen production evoked by upregulated HSP72. In summary, the present study unveils an inhibitory role of HSP72 in tendon adhesion via inactivation of the STAT3 signaling pathway. This finding may enable the development of new therapeutic strategies for the prevention against tendon adhesion.

8.
Anal Chim Acta ; 1107: 48-54, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32200901

RESUMO

This work designed an anchored monopodial DNA walker to amplify amperometric biosensing signal for sensitive detection of nucleic acid and protein. The biosensing surface was constructed by self-assembling hairpin DNA1 (H1) and small amount of P1-W (probe DNA1 hybridized with walking DNA) on a gold electrode. In the presence of target molecule, the walker could be triggered by the surface proximity hybridization product of P1, target and P2 to induce the cyclic hybridization of H1 with ferrocene modified hairpin DNA2 (H2-Fc), which took electroactive Fc to the electrode surface for amplified amperometric detection of the target. By linking P1 and P2 with dual specific DNA strands, aptamers or antibodies to recognize the target for proximity hybridization of P1 and P2, the walker amplified amperometric strategy could be used for highly sensitive biosensing of different targets. Using DNA and thrombin as the target models, the proposed biosensing methods achieved the linear range from 0.2 pM to 2 nM with a detection limit of 0.11 pM and 1.0 pM to 10 nM with a detection limit of 0.61 pM, respectively. The specific recognition process endowed the strategy with high selectivity and potential applications.

9.
J Mater Chem B ; 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32207759

RESUMO

It has been proved that silicon-substituted calcium phosphate ceramics possess superior bone regeneration and resorbability to HA, while the synthesis of single-phase nanocrystallized high Si-containing calcium phosphate is still a challenge. In the present work, a novel and facile aqueous precipitation method assisted with ultrasonic irradiation was adopted firstly to synthesise a single-phase nanocrystallized calcium silicophosphate (Ca5(PO4)2SiO4, CPS) biomaterial. Crystallization and morphology of Si-apatite precursors synthesized with or without ultrasonic assistance were primarily investigated and the related mechanism was discussed. Moreover, the sinterability, in vitro bioactivity and osteogenic activity of the synthesized CPS were studied in detail. Results showed that an ultrasonic cavitation effect could be beneficial to form a highly dispersive CPS precursor with a single Si-apatite phase, which greatly reduced the calcination temperature of CPS from 1350 °C to 1000 °C. Nanocrystallized CPS powders were obtained successfully under ultrasound-assisted conditions, which showed superior sinterability, in vitro bioactivity and osteogenic activity than those of micron-sized CPS and HA powders. It might be a promising candidate material for bone tissue regeneration applications.

10.
Protein Cell ; 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32125673

RESUMO

In the original publication the bands in Fig. 1J and Fig. 2B were not visible. The correct versions of Fig. 1J and Fig. 2B are provided in this correction.

13.
Lab Chip ; 20(5): 1002-1011, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32026889

RESUMO

Integration of microfluidics and biosensing functionalities on a single device holds promise in continuous health monitoring and disease diagnosis for point-of-care applications. However, the required functions of fluid handling and biomolecular sensing usually arise from different actuation mechanisms. In this work, we demonstrate that a single acoustofluidic device, based on a flexible thin film platform, is able to generate hybrid wave modes, which can be used for fluidic actuation (Lamb waves) and biosensing (thickness shear waves). On this integrated platform, we show multiple and sequential functions of mixing, transport and disposal of liquid volumes using Lamb waves, whilst the thickness bulk shear waves allow us to sense the chemotherapeutic Imatinib, using an aptamer-based strategy, as would be required for therapy monitoring. Upon binding, the conformation of the aptamer results in a change in coupled mass, which has been detected. This platform architecture has the potential to generate a wide range of simple sample-to-answer biosensing acoustofluidic devices.

14.
J Mater Chem B ; 8(11): 2363-2370, 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32104865

RESUMO

Ultra-high sensitivity is difficult to achieve using conventional enzymatic glucose biosensors due to the lack of exposed active sites and steric-hinderance effects. Thus, in the present study, we report a photoelectrochemical (PEC) enzymatic glucose biosensor based on 3-dimensional (3D) hollow-out titanium dioxide (TiO2) nanowire cluster (NWc)/glucose oxidase (GOx), providing more number of exposed active sites, thus constructing a sensor with a higher affinity toward glucose reaction. Excellent performance with an ultra-high sensitivity of 58.9 µA mM-1 cm-2 and 0-2 mM linear range with a determination limit of 8.7 µM was obtained for the detection of glucose. This study might provide a new approach to expose active sites efficiently for remarkable photoelectrochemical performances.

15.
J Am Chem Soc ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32031790

RESUMO

State-of-the-art, high-performance perovskite solar cells (PSCs) contain a large amount of iodine to realize smaller bandgaps. However, the presence of numerous iodine vacancies at the surface of the film formed by their evaporation during the thermal annealing process has been broadly shown to induce deep-level defects, incur nonradiative charge recombination, and induce photocurrent hysteresis, all of which limit the efficiency and stability of PSCs. In this work, modifying the defective surface of perovskite films with cadmium iodide (CdI2) effectively reduces the degree of surface iodine deficiency and stabilizes iodine ions via the formation of strong Cd-I ionic bonds. This largely reduces the interfacial charge recombination loss, yielding a high efficiency of 21.9% for blade-coated PSCs with an open-circuit voltage of 1.20 V, corresponding to a record small voltage deficit of 0.31 V. The CdI2 surface treatment also improves the operational stability of the PSCs, retaining 92% efficiency after constant illumination at 1 sun intensity for 1000 h. This work provides a promising strategy to optimize the surface/interface optoelectronic properties of perovskites for more efficient and stable solar cells and other optoelectronic devices.

16.
Radiother Oncol ; 145: 186-192, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32044531

RESUMO

BACKGROUND AND PURPOSE: Manual delineation of clinical target volumes (CTVs) and organs at risk (OARs) is time-consuming, and automatic contouring tools lack clinical validation. We aimed to construct and validate the use of convolutional neural networks (CNNs) to set better contouring standards for rectal cancer radiotherapy. MATERIALS AND METHODS: We retrospectively collected and evaluated computed tomography (CT) scans of 199 rectal cancer patients treated at our hospital from February 2018 to April 2019. Two CNNs-DeepLabv3+ for extracting high-level semantic information and ResUNet for extracting low-level visual features-were used for the CTV and small intestine contouring, and bladder and femoral head contouring, respectively. Contouring quality was compared using the paired t test. Five-point objective grading was performed independently by two experienced radiation oncologists and verified by a third. The CNN manual correction time was recorded. RESULTS: CTVs calculated using DeepLabv3+ (CTVDeepLabv3+) had significant quantitative parameter advantages over CTVResUNet (volumetric Dice coefficient, 0.88 vs 0.87, P = 0.0005; surface Dice coefficient, 0.79 vs 0.78, P = 0.008). Among 315 graded cases, DeepLabv3+ obtained the highest scores with 284 cases, consistent with the objective criteria, whereas CTVResUNet had the minimum mean manual correction time (7.29 min). DeepLabv3+ performed better than ResUNet for small intestine contouring and ResUNet performed better for bladder and femoral head contouring. The manual correction time for OARs was <4 min for both models. CONCLUSION: CNNs at various feature resolution levels well delineate rectal cancer CTVs and OARs, displaying high quality and requiring shorter computation and manual correction time.

17.
Drug Des Devel Ther ; 14: 457-468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099330

RESUMO

Background: Metformin has been shown to inhibit the proliferation and migration of vascular wall cells. However, the mechanism through which metformin acts on atherosclerosis (AS) via the long non-coding RNA taurine up-regulated gene 1 (lncRNA TUG1) is still unknown. Thus, this research investigated the effect of metformin and lncRNA TUG1 on AS. Methods: First, qRT-PCR was used to detect the expression of lncRNA TUG1 in patients with coronary heart disease (CHD). Then, the correlation between metformin and TUG1 expression in vitro and their effects on proliferation, migration, and autophagy in vascular wall cells were examined. Furthermore, in vivo experiments were performed to verify the anti-AS effect of metformin and TUG1 to provide a new strategy for the prevention and treatment of AS. Results: qRT-PCR results suggested that lncRNA TUG1 expression was robustly upregulated in patients with CHD. In vitro experiments indicated that after metformin administration, the expression of lncRNA TUG1 decreased in a time-dependent manner. Metformin and TUG1 knockdown via small interfering RNA both inhibited proliferation and migration while promoted autophagy via the AMPK/mTOR pathway in vascular wall cells. In vivo experiments with a rat AS model further demonstrated that metformin and sh-TUG1 could inhibit the progression of AS. Conclusion: Taken together, our data demonstrate that metformin might function to prevent AS by activating the AMPK/mTOR pathway via lncRNA TUG1.

18.
Artigo em Inglês | MEDLINE | ID: mdl-32107913

RESUMO

The development of solution-processed inorganic amorphous electron-transporting layers (ETLs) is important for the future commercialization of perovskite solar cells (PSCs). The formation of such ETLs using low-temperature processing techniques will lower potential production costs and accommodate diverse substrate materials. Herein, a low-temperature (<150 °C) solution process forms amorphous titania nanowire (Am-TNW) thin films on fluorine-doped tin oxide conducting glass substrates. When applied as an ETL in PSCs, the Am-TNW layer achieves a higher average power conversion efficiency (18.3%) relative to that of a nanocrystalline anatase TNW (ATNW) layer obtained after high-temperature (500 °C) heating (16.7%). Compared to the ATNW counterparts, the Am-TNW-based PSCs exhibit inferior charge extraction across the TNW/CH3NH3PbI3 interface but more effectively suppress interfacial charge recombination. The insertion of a fullerene layer between the Am-TNW and CH3NH3PbI3 improves the charge extraction. The Am-TNW-based bilayer ETL gave optimal power conversion efficiencies of 20.3% and 19.0% for PSCs with 0.16 cm2 and 1.00 cm2 apertures, respectively. This is due to the concurrent advantages of enhanced light absorption, facilitated charge extraction, and reduced charge recombination. The use of the Am-TNW as an ETL in PSCs provides a facile, efficient way to increase the effectiveness of PSCs.

19.
J Surg Oncol ; 121(3): 570-577, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31902136

RESUMO

BACKGROUND: Joint-preserving intercalary tumor resection can result in better proprioception and a more normal joint function after reconstruction. However, most reported reconstruction techniques are usually associated with frequent complications. Therefore, the approach of reconstruction following joint-preserving tumor resection warrants further study. METHODS: Between September 2016 and October 2018, 12 patients with metaphyseal malignant bone tumors around the knee joint were treated by joint-preserving intercalary resections with the aid of three-dimensional (3D)-printed osteotomy guide plates and reconstructions using 3D-printed intercalary prostheses. We assessed the accuracy of the resection by comparing the cross sections at the resection plane with 3D-printed matching surface of the prostheses. The functional outcomes, complications and oncological status were also evaluated. RESULTS: All patients were observed for 7 to 32 months with an average follow-up of 22.5 months. The achieved resection was accurate, with accurate matching between the residual bone and prosthesis. The mean MSTS score was 28 (range, 26-30). Superficial infection occurred in two patients. Local recurrence was observed in one patient, while pulmonary metastasis was identified in one patient. CONCLUSIONS: The personalized osteotomy guide plate and prosthesis based on 3D printing technique facilitate joint-preserving tumor resection and functional reconstruction. However, longer follow-up and larger sample size are required to clarify its long-term outcomes. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Doenças Ósseas/cirurgia , Neoplasias Ósseas/cirurgia , Articulação do Joelho/cirurgia , Tratamentos com Preservação do Órgão/métodos , Impressão Tridimensional/instrumentação , Implantação de Prótese , Procedimentos Cirúrgicos Reconstrutivos/métodos , Adolescente , Adulto , Neoplasias Ósseas/patologia , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteotomia , Prognóstico , Desenho de Prótese , Estudos Retrospectivos
20.
Analyst ; 145(4): 1190-1194, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31894761

RESUMO

Graphene oxide (GO) is capable of quenching fluorescence in bound fuel single stranded DNA (ssDNA) labeled with dye. In the presence of target microRNA let-7a, two cascaded toehold-mediated strand displacement reactions (TSDRs) were triggered, thereby desorbing substantial π-π stacking adsorbed fuel DNA from GO through recycling amplification, simultaneously accompanied with the restoration of dye fluorescence. By coupling dsDNA-AuNPs with the GO nanosheet, the proposed strategy achieved a non-enzymatic sensitive assay with a low detection limit of 3.9 pM. Hence, the proposed approach has great potential for applications in early cancer diagnosis and clinical analysis.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA