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1.
Zhongguo Gu Shang ; 33(5): 465-9, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32452187

RESUMO

OBJECTIVE: To evaluate the cartilage regeneration in the knee joint by arthroscopy after high tibial osteotomy. METHODS: Eleven patients were included in the study who were treated with high tibial osteotomy and underwent microscopy when the internal fixation was unloaded from September 2017 to September 2019. Among them, there were 2 males and 9 females, aged from 55 to 64 years old. The internal and external compartment pictures of the knee were taken before and after surgery of removing the internal fixation and the International Cartilage Repair Society (ICRS) grading systerm was used to evaluate the degree of cartilage damage on the medial and lateral femoralcondyles and tibial plateau. The Westrn Ontarioand Mcmaster Universities osteoarthritis index (WOMAC) and the weight bearing line (WBL) were used to evaluate the function of the knee and the alignment of the lower limb. RESULTS: All 8 patients were followed up for more than 12 months, ranging from 12 to 22 months. The degenerated cartilage of the medial femoral condyle and medial tibial plateau was covered by newly regenerated cartilage. WOMAC score decreased from 102-127 to 41-52 and WBL was improved from 17%-34% to 58%-64%. All incisions healed in stageⅠ, and no complications such as internal fixation rupture and infection occurred during and after the operation. CONCLUSION: High tibial osteotomy can relieve the pain of the knee and the dysfunction by adjusting lower limb alignment, and the degenerated cartilage could be regenerated in the medial femoral condyle and medial tibial plateau.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32380829

RESUMO

Three-dimensional (3D) plasmonic nanostructures are emerging as excellent surface-enhanced Raman spectroscopy (SERS) substrates for chemical and biomedical applications. However, the correlation of the 3D (including both of the in-plane and out-of-plane) plasmonic coupling with the SERS properties to deepen the understanding of 3D SERS substrates remains a challenge. Here, we perform correlated studies of 3D plasmonic coupling and SERS properties of the 3D hierarchical SERS substrates by tuning the multiscale structural elements. The effect of 0D (the size of building blocks), 1D (the thickness of the 3D substrates) and 2D (the composition of individual monolayers) structural elements on 3D plasmonic coupling are studied by measuring the UV-Vis-NIR spectroscopy and SERS performance. It shows that both of the extinction spectra and SERS enhancement are tuned at the 3D structural level. It is demonstrated that the plasmonic resonance wavelength (PRW) stemmed from the 3D plasmonic coupling is correlated with the SERS averaged surface enhancement factor (ASEF), and which is improved by over 10-fold at the optimum 3D nanostructure. The optimized substrate is used to quantitatively analyze two small biological molecules. Moreover, as a proof-of-concept study, the substrate is first applied to differentiate between living liver normal and cancer cells with a high prediction accuracy through the spectral features of the cell membranes and the metabolites secreted outside the cells. We expect that the tuning of plasmonic coupling at 3D level can open up new routes to design high performance SERS substrates for wide applications.

3.
Zhongguo Gu Shang ; 33(3): 214-8, 2020 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-32233246

RESUMO

OBJECTIVE: To observe early clinical effect of high tibial osteotomy combined with arthroscopy for elderly patients with knee osteoarthritis of medial compartment. METHODS: Sixty-one elderly patients with medial compartment knee osteoarthritis were treated with high tibial osteotomy combined with arthroscopy from August 2017 to October 2018. Among them, including 17 males and 44 females, aged from 60 to 83 years old with an average of (67.87±6.45) years old. Weight bearing line (WBL) and femora-tibial angle (FTA) were analyzed to assess lower limb alignment before and 12 months after surgery. Visual analogue scale (VAS) score and Hospital for Special Surgery (HSS) score were used to evaluate knee pain and function before and 1, 3, 12 months after surgery. RESULTS: All patients were followed up from 12 to 19 months with an average of (14.27±4.69) months. WBL was improved from (14.79±5.61) % before operation to (59.33±7.82) % at 12 months after operation (t=2.294, P<0.05), FTA was improved from (182.14±2.19) ° before operation to (171.54±3.16) ° at 12 months after operation (t=1.827, P<0.05) . VAS score decreased from 6.14±2.21 before operation to 3.64±0.92, 2.02±0.63 and 0.93±0.61 at 1, 3 and 12 months after operation (F=458.24, P<0.001), HSS score increased from 49.66±13.79 to 58.39±9.26, 71.82±6.06 and 82.71±6.97 at 1, 3 and 12 months after operation (F=266.45, P<0.001) . Three patients had contralateral cortical fracture during surgery, whose osteotomy area healed well at 12 months after surgery. The incision healing of 4 cases was slow, while all healed at 3 to 4 weeks after surgery. CONCLUSION: High tibial osteotomy combined with arthroscopy could adjust lower limb alignment effectively, relieve knee pain and functional dysfunction, which indicated a significant short term efficacy on the elderly patients with knee osteoarthritis of medial compartment.


Assuntos
Osteoartrite do Joelho , Idoso , Idoso de 80 Anos ou mais , Artroscopia , Feminino , Humanos , Articulação do Joelho , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Osteotomia , Tíbia , Resultado do Tratamento
4.
Biosens Bioelectron ; 154: 112067, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32056962

RESUMO

The creatinine concentration of human urine is closely related to human kidney health and its rapid, quantitative, and low-cost detection has always been demanded. Herein, a surface-enhanced Raman spectroscopic (SERS) method for rapid and cost-effective quantification of creatinine concentrations in human urine was developed. A Au nanoparticle solution (Au sol) was used as a SERS substrate and the influence of different agglomerating salts on its sensitivity toward detecting creatinine concentrations was studied and optimized, as well as the effect of both the salt and Au sol concentrations. The variation in creatinine spectra over time on different substrates was also examined, demonstrating reproducible quantitative analysis of creatinine concentrations in solution. By adjusting the pH, a simple liquid-liquid solvent extraction procedure, which extracted creatinine from human urine, was used to increase the SERS detection selectivity toward creatinine in complex matrices. The quantitative results were compared to those obtained with a clinically validated enzymatic "creatinine kit (CK)." The limit of detection (LOD) for the SERS technique was 1.45 mg L-1, compared with 3.4 mg L-1 for the CK method. Furthermore, cross-comparing the results from the two methods, the average difference was 5.84% and the whole SERS detection process could be completed within 2 min compared with 11 min for the CK, indicating the practicality of the quantitative SERS technique. This novel quantitative technique shows promises as a high-throughput platform for relevant clinical and forensic analysis.

5.
Anal Chem ; 90(12): 7275-7282, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29772173

RESUMO

The realization of surface-enhanced Raman spectroscopy (SERS) to be a reliable quantitative analytical technique requires sensitive and reproducible enhancing substrates. Here, uniform three-dimensional (3D) Ag nanorod (AgNR) substrates with well-defined interlayer spacings are prepared through the air-liquid interface-assisted self-assembly of AgNR in a layer-by-layer manner. The correlation of the SERS performance with the 3D AgNR structures is performed by SERS mapping the substrates. SERS mapping reveals the excellent enhancement uniformity of the 3D substrates with the relative standard deviation (RSD) less than 10%. It finds that both of the number of layers (NL) and the length of the AgNR have effects on the SERS performance of the 3D AgNR substrates. It is demonstrated that the intergaps between layers contribute much to the SERS intensity of the 3D AgNR by creating the interlayer (out-of-plane) plasmonic coupling. The impact of the excitation wavelengths (532, 633, and 785 nm) on SERS performance is also determined. The optimal 3D AgNR structures achieved by the correlation study is further used to detect a set of related molecules (l-tryptophan (Trp), l-phenylalanine (Phe), urea, and melamine). The 3D AgNR SERS of the analytes exhibits linear responses over wide concentration ranges. The sensitivity of the 3D AgNR SERS is proved by comparing to that of the current methods. Moreover, the 3D AgNR substrates maintain the performance stability during 4 weeks of storage.

6.
Clin Spine Surg ; 29(8): E396-400, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27642778

RESUMO

STUDY DESIGN: Retrospective. OBJECTIVES: We determined values for the volume of right lung (Vr), left lung (Vl), total lung volume (Vt), and left/right lung volume ratio (Vl/Vr), allowing comparison between those data measured and those of age-matched controls. To find whether lung volume correlates with preoperative pulmonary function. SUMMARY OF BACKGROUND DATA: To our knowledge, no study on relationship between computed tomographic (CT) scans determined lung volume and pulmonary function test (PFT) in scoliosis have been published. METHODS: All examinations with PFT (31 cases) were identified. Three-dimensional volumetric reconstruction of lung parenchyma was performed on existing preoperative CT scans for 26 idiopathic scoliosis patients. Vl, Vr, Vt, Vl/Vr, and absolute value of right volume minus left volume (|Vr-Vl|) were calculated and correlated with PFTs. To determine if significant difference of preoperative lung volume exists between idiopathic scoliosis patients and controls. Linear regression models, using 3-dimensional lung volume parameters as predictors for vital capacity (VC), forced vital capacity (FVC), and total lung capacity (TLC), were created. RESULTS: Vt was positively correlated with VC, FVC, forced expiratory volume in 1 second (FEV1), TLC, predicted value for FVC (FVC%), predicted value for FEV1 (FEV1%), predicted value for TLC (TLC%), and predicted value for maximal ventilator volume (MVV%) (P<0.05); |Vr-Vl| was not correlated with ventilation parameters (P>0.05); Diffusion parameters were not correlated with CT-reconstructed lung volume parameters (P>0.05); male and female adolescent idiopathic scoliosis patients had less Vt, Vr, and Vl compared with those of age-matched controls (P<0.05). CONCLUSIONS: Vt was positively correlated with VC, FVC, FEV1, TLC, FVC%, FEV1%, TLC%, and MVV%. Vt, Vr, and Vl of adolescent idiopathic scoliosis patients were less than those of age-matched controls.


Assuntos
Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Tecido Parenquimatoso/diagnóstico por imagem , Escoliose/diagnóstico por imagem , Escoliose/fisiopatologia , Tomografia Computadorizada por Raios X , Adolescente , Estudos de Casos e Controles , Criança , Estudos de Coortes , Feminino , Humanos , Imageamento Tridimensional , Modelos Lineares , Masculino , Testes de Função Respiratória , Escoliose/patologia , Adulto Jovem
7.
Nanoscale ; 8(5): 2951-9, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26782014

RESUMO

Nanostructures with symmetry breaking can allow the coupling between dark and bright plasmon modes to induce strong Fano resonance. However, it is still a daunting challenge to prepare bottom-up self-assembled subwavelength asymmetric nanostructures with appropriate gaps between the nanostructures especially below 5 nm in solution. Here we present a viable self-assembly method to prepare symmetry-breaking nanostructures consisting of Ag nanocubes and Au nanospheres both with tunable size (90-250 nm for Au nanospheres; 100-160 nm for Ag nanocubes) and meanwhile control the nanogaps through ultrathin silica shells of 1-5 nm thickness. The Raman tag of 4-mercaptobenzoic acid (MBA) assists the self-assembly process and endows the subwavelength asymmetric nanostructures with surface-enhanced Raman scattering (SERS) activity. Moreover, thick silica shells (above 50 nm thickness) can be coated on the self-assembled nanostructures in situ to stabilize the whole nanostructures, paving the way toward bioapplications. Single particle scattering spectroscopy with a 360° polarization resolution is performed on individual Ag nanocube and Au nanosphere dimers, correlated with high-resolution TEM characterization. The asymmetric dimers exhibit strong configuration and polarization dependence Fano resonance properties. Overall, the solution-based self-assembly method reported here is opening up new opportunities to prepare diverse multicomponent nanomaterials with optimal performance.

8.
Anal Chem ; 87(7): 3791-9, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25751526

RESUMO

Shell-isolated gold nanoparticles (SHINs) were employed to record shell-isolated nanoparticle-enhanced Raman spectra (SHINERS) of a passive layer formed at a gold surface during gold leaching from thiosulfate solutions. The (3-aminopropyl)triethoxysilane (APTES) and a sodium silicate solution were used to coat gold nanoparticles with a protective silica layer. This protective silica layer prevented interactions between the thiosulfate electrolyte and the gold core of the SHINs when the SHINs-modified gold electrode was immersed into the thiosulfate lixiviant. The SHINERS spectra of the passive layer, formed from thiosulfate decomposition, contained bands indicative of hydrolyzed APTES. We have demonstrated how to exploit the presence of these APTES bands as an internal standard to compensate for fluctuations of the surface enhancement of the electric field of the photon. We have also developed a procedure that allows for removal of the interfering APTES bands from the SHINERS spectra. These methodological advancements have enabled us to identify the species forming the passive layer and to determine that the formation of elemental sulfur, cyclo-S8, and polymeric sulfur chains is responsible for inhibition of gold dissolution in oxygen rich thiosulfate solutions.

9.
Nano Lett ; 13(4): 1816-21, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23458121

RESUMO

Locally probing chemical reactions or catalytic processes on surfaces under realistic reaction conditions has remained one of the main challenges in materials science and heterogeneous catalysis. Where conventional surface interrogation techniques usually require high-vacuum conditions or ensemble average measurements, plasmonic nanoparticles excel in extreme light focusing and can produce highly confined electromagnetic fields in subwavelength volumes without the need for complex near-field microscopes. Here, we demonstrate an all-optical probing technique based on plasmonic smart dust for monitoring local chemical reactions in real time. The silica shell-isolated gold nanoparticles that form the smart dust can work as strong light concentrators and optically report subtle environmental changes at their pinning sites on the probed surface during reaction processes. As a model system, we investigate the hydrogen dissociation and subsequent uptake trajectory in palladium with both "dust-on-film" and "film-on-dust" platforms. Using time-resolved single particle measurements, we demonstrate that our technique can in situ encode chemical reaction information as optical signals for a variety of surface morphologies. The presented technique offers a unique scheme for real-time, label-free, and high-resolution probing of local reaction kinetics in a plethora of important chemical reactions on surfaces, paving the way toward the development of inexpensive and high-output reaction sensors for real-world applications.


Assuntos
Fenômenos Químicos , Ouro/química , Hidrogênio/química , Dióxido de Silício/química , Catálise , Cinética , Microscopia
10.
Nat Protoc ; 8(1): 52-65, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23237829

RESUMO

Surface-enhanced Raman scattering (SERS) is a powerful fingerprint vibrational spectroscopy with a single-molecule detection limit, but its applications are generally restricted to 'free-electron-like' metal substrates such as Au, Ag and Cu nanostructures. We have invented a shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) technique, using Au-core silica-shell nanoparticles (Au@SiO(2) NPs), which makes SERS universally applicable to surfaces with any composition and any morphology. This protocol describes how to prepare shell-isolated nanoparticles (SHINs) with different well-controlled core sizes (55 and 120 nm), shapes (nanospheres, nanorods and nanocubes) and shell thicknesses (1-20 nm). It then describes how to apply SHINs to Pt and Au single-crystal surfaces with different facets in an electrochemical environment, on Si wafer surfaces adsorbed with hydrogen, on ZnO nanorods, and on living bacteria and fruit. With this method, SHINs can be prepared for use in ~3 h, and each subsequent procedure for SHINERS measurement requires 1-2 h.


Assuntos
Nanoconchas/química , Análise Espectral Raman/métodos , Adsorção , Parede Celular/ultraestrutura , Citrus sinensis/química , Frutas/química , Ouro/química , Hidrogênio/química , Microscopia Eletrônica de Transmissão , Nanotubos/química , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/química , Platina/química , Dióxido de Silício/química , Propriedades de Superfície , Leveduras/ultraestrutura , Óxido de Zinco/química
11.
J Agric Food Chem ; 57(21): 10392-8, 2009 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-19827789

RESUMO

Samples from naked oat were steeped and germinated under controlled conditions in an incubator. Changes of phenolic compounds and antioxidant activity were investigated in oats during steeping and germination. Results revealed that phenolic compounds and antioxidant activity of oats varied with the difference in steeping and germination stages. Compared with raw grains, short-term steeping treatment did not show significant effects (p > 0.05) on phenolic content. Germination can significantly result in the decrease in bound phenolic and the increase in free and total phenolics. Main phenolic acids and avenanthramides were isolated and quantified by HPLC analysis. During steeping, phenolic acids decreased (p < 0.05); avenanthramide N-(3',4'-dihydroxy)-(E)-cinnamoyl-5-hydroxyanthranilic acid first decreased and then increased (p < 0.05), while avenanthramides N-(4'-hydroxy)-(E)-cinnamoyl-5-hydroxyanthranilic acid and N-(4'-hydroxy-3'-methoxy)-(E)-cinnamoyl-5-hydroxyanthranilic acid did not change significantly (p > 0.05). During germination, gallic and caffeic acids first increased (p < 0.05) and then decreased, whereas p-coumaric and ferulic acids and avenanthramides increased (p < 0.05). Nevertheless, avenanthramides did not change significantly (p > 0.05) during the last stage of germination. Oat extracts exhibited increasing high antioxidant activity with the steeping and germination going on, which may explain that antioxidant activity correlated (p < 0.01) significantly with the content of phenolic compounds.


Assuntos
Antioxidantes/análise , Avena/química , Avena/fisiologia , Germinação , Fenóis/análise
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