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1.
J Sep Sci ; 45(3): 752-759, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34856052

RESUMEN

In this paper, a flower-like molybdenum disulfide material was prepared by hydrothermal method and was first used as adsorbents in the solid-phase extraction process for enriching N-nitrosoamines. Molybdenum disulfide exhibited three-dimensional petal-like microspheres with about 500 nm in diameter. The relevant analyte extraction and elution parameters (sample volumes, solution pH, washing solvents, elution solvents, and elution volumes) were optimized to improve the solid-phase extraction efficiency. The solid-phase extraction process coupled with high-performance liquid chromatography-tandem mass spectrometry for determining N-nitrosoamines in environmental water samples was established. The limits of detection were in the range of 0.01-0.05 ng/mL. The satisfactory recoveries (68.9-106.1%) were obtained at three different spiked concentrations (2, 5, and 8 ng/mL) in water samples, and the relative standard deviations were between 1.96 and 8.38%. This proposed method not only showed high sensitivity and good reusability but also provided a new adsorbent for enriching trace N-nitrosoamines in environmental water samples.

2.
Methods ; 168: 76-83, 2019 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-31301376

RESUMEN

Biocompatible fluorescent carbon dots (CDs) were prepared via a simple and green route using duck breasts as a natural carbon source. The CDs from duck breasts were well dispersed, and their mean particle size decreased from 2.59 to 1.95 nm when the roasting temperature increased from 200 to 300 °C. Abundant functional groups such as OH, COOH, and NH2 were observed on the surface of the CDs, providing the CDs with good water solubility. These CDs emitted strong fluorescence under ultraviolet light irradiation and exhibited superior photostability. The absolute fluorescence quantum yield of CDs rose from 10.53% to 38.05% when the relative nitrogen content of CDs increased from 7.18% to 12.73%. The CDs showed low toxicity to PC12 cells for prolonged exposure. Therefore, the duck CDs were successfully developed as fluorescent probes for in vitro PC12 cells and in vivo Caenorhabditis elegans imaging. These results indicated that the CDs derived from roast duck were biocompatible and can potentially be used as probes in bio-imaging.


Asunto(s)
Caenorhabditis elegans/aislamiento & purificación , Carbono/química , Carne , Puntos Cuánticos/química , Animales , Materiales Biocompatibles/química , Culinaria , Patos , Fluorescencia , Concentración de Iones de Hidrógeno , Iones , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión , Nitrógeno , Células PC12 , Aves de Corral , Ratas , Solubilidad , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Temperatura
3.
Cell Biochem Funct ; 38(2): 231-238, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31710120

RESUMEN

Regeneration remains a major challenge in skeletal muscle repair after injury. Recently, transforming growth factor-ß (TGF-ß)/Smad pathway was found to play an important role in inhibiting myogenesis, a crucial stage in skeletal muscle regeneration. In our previous study, microRNA-122-5p (miR-122) was proved to have the function of downregulating TGF-ß/Smad pathway. Theoretically, miR-122 might also be involved in the process of skeletal muscle myogenesis through the regulation of TGF-ß/Smad pathway. In this study, we aimed to investigate the impact of miR-122 on skeletal muscle myogenesis and explore its underlying mechanism. Results showed that miR-122 and myogenic markers were downregulated in C2C12 cells after TGF-ß stimulation, and miR-122 overexpression could restore the myogenesis inhibited by TGF-ß. We then located TGFBR2 as the direct target of miR-122 and discovered the effect of miR-122 overexpression could be rescued by TGFBR2 overexpression. Further, the downstream molecules of TGFBR2 in the TGF-ß/Smad pathway were found to be suppressed by miR-122. In conclusion, miR-122 could suppress the TGF-ß/Smad signalling pathway by directly targeting TGFBR2 and, consequently, restore myogenesis. SIGNIFICANCE OF THE STUDY: Regeneration remains a major challenge in skeletal muscle repair after injury. In this study, it was found that miR-122 could suppress the TGF-ß/Smad signalling pathway by directly targeting TGFBR2 and, consequently, restore myogenesis. Our findings could inspire future experiments on the role of miRs in skeletal muscle diseases and future translational studies on potential novel gene therapy for skeletal muscle injury.


Asunto(s)
MicroARNs/metabolismo , Desarrollo de Músculos , Músculo Esquelético/metabolismo , Receptor Tipo II de Factor de Crecimiento Transformador beta/metabolismo , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Células HEK293 , Humanos , Ratones , Regeneración , Transducción de Señal
4.
Entropy (Basel) ; 21(8)2019 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-33267465

RESUMEN

In this paper, we propose a Lyapunov-based state feedback control for state transfer based on the on-line quantum state estimation (OQSE). The OQSE is designed based on continuous weak measurements and compressed sensing. The controlled system is described by quantum master equation for open quantum systems, and the continuous measurement operators are derived according to the dynamic equation of system. The feedback control law is designed based on the Lyapunov stability theorem, and a strict proof of proposed control laws are given. At each sampling time, the state is estimated on-line, which is used to design the control law. The simulation experimental results show the effectiveness of the proposed feedback control strategy.

5.
Food Chem X ; 23: 101530, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-38933991

RESUMEN

Osteoporosis is a systemic bone disease characterized by reduced bone mass and deterioration of the microstructure of bone tissue, leading to an increased risk of fragility fractures and affecting human health worldwide. Food-derived peptides are widely used in functional foods due to their low toxicity, ease of digestion and absorption, and potential to improve osteoporosis. This review summarized and discussed methods of diagnosing osteoporosis, treatment approaches, specific peptides as alternatives to conventional drugs, and the laboratory preparation and identification methods of peptides. It was found that peptides interacting with RGD (arginine-glycine-aspartic acid)-binding active sites in integrin could alleviate osteoporosis, analyzed the interaction sites between these osteogenic peptides and integrin, and further discussed their effects on improving osteoporosis. These may provide new insights for rapid screening of osteogenic peptides, and provide a theoretical basis for their application in bone materials and functional foods.

6.
ScientificWorldJournal ; 2013: 967529, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23766732

RESUMEN

The condition of a quantum Lyapunov-based control which can be well used in a closed quantum system is that the method can make the system convergent but not just stable. In the convergence study of the quantum Lyapunov control, two situations are classified: nondegenerate cases and degenerate cases. For these two situations, respectively, in this paper the target state is divided into four categories: the eigenstate, the mixed state which commutes with the internal Hamiltonian, the superposition state, and the mixed state which does not commute with the internal Hamiltonian. For these four categories, the quantum Lyapunov control methods for the closed quantum systems are summarized and analyzed. Particularly, the convergence of the control system to the different target states is reviewed, and how to make the convergence conditions be satisfied is summarized and analyzed.


Asunto(s)
Algoritmos , Retroalimentación , Modelos Teóricos , Teoría Cuántica , Simulación por Computador
7.
Naunyn Schmiedebergs Arch Pharmacol ; 396(9): 2165-2177, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36961550

RESUMEN

This research used network pharmacology, molecular docking, in vivo studies, and other techniques to investigate the biological activity and mechanism of action of urolithin A (UA) in treating combined allergic rhinitis and asthma syndrome (CARAS). Urolithin A and potential related targets of allergic rhinitis and asthma were searched from the public databases. Then, bioinformatics analyses were given to protein-protein interaction (PPI), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG). Subsequently, molecular docking and molecular dynamic simulation were performed, aiming at predicting the binding of the active compound to the core target. Finally, in vivo experiment was conducted for further validation. A total of 45 common targets of allergic rhinitis and urolithin A and 62 common targets of asthma and urolithin A were identified, among which six common core targets were screened with Cytoscape. Molecular docking indicated that these core targets had good binding activity to urolithin A, which was further confirmed by molecular dynamics simulation. In the CARAS mouse model, urolithin A showed anti-inflammatory properties. The biological activity and regulatory network of UA on CARAS were revealed, and the anti-inflammatory effect of UA was clarified, which could be associated with the equilibrium of the immune system's Th1/Th2 cells.


Asunto(s)
Asma , Rinitis Alérgica , Animales , Ratones , Simulación del Acoplamiento Molecular , Farmacología en Red , Rinitis Alérgica/tratamiento farmacológico , Asma/tratamiento farmacológico
8.
Anal Chim Acta ; 1239: 340654, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36628750

RESUMEN

Novel Fe3O4-Ag-MnO2 composites were successfully synthesized. It was noteworthy that the obtained Fe3O4-Ag-MnO2 composites were found to possess three types of enzyme-mimicking activities, including peroxidase-like, catalase-like and oxidase-like activities. Taking advantage of the oxidase properties of Fe3O4-Ag-MnO2, the direct oxidation of TMB could be catalyzed to generate blue oxidation products without H2O2. The oxidase-like activity of Fe3O4-Ag-MnO2 were carefully studied. Based on the Fe3O4-Ag-MnO2-TMB system, a fast, sensitive and intuitive multicolor colorimetric method for Staphylococcus aureus (S. aureus) detection was established under the optimized conditions. The proposed method allows the detection of S. aureus with a detection limit of 3.7 cfu mL-1 and a linear range of 10-106 cfu mL-1. This new colorimetric method has been successfully proved to be applicable to the detection S. aureus of food samples.


Asunto(s)
Óxidos , Staphylococcus aureus , Colorimetría/métodos , Compuestos de Manganeso , Peróxido de Hidrógeno , Oxidorreductasas
9.
IEEE Trans Cybern ; 52(10): 11213-11225, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34343103

RESUMEN

For stochastic quantum systems with measurement feedback, this article proposes a rapid switching control scheme based on state space partition and realizes the rapid stabilization of an eigenstate of an observable operator. Meanwhile, we apply the proposed scheme to the preparation of typical entangled states in multiqubit systems. In view of the convergence obstacle caused by the symmetric structure of the state space, especially in the case with degenerate observable operators, we first partition the state space into a subset containing the target state and its complement to distinguish the target state from its antipodal points, and then design the corresponding control laws in these two subsets, respectively, by using different Lyapunov functions. The interaction Hamiltonians are also constructed to drive the system state to the desired subset first, and further to the target state. In particular, the control law designed in the undesired subset guarantees the strictly monotonic descent of the corresponding Lyapunov function, which makes the system trajectory switch between the two subsets at most twice and has the potential to speed up the convergence process. We also prove the stability of the closed-loop system with the proposed switching control law based on the stochastic Lyapunov stability theory. By applying the proposed switching control scheme to a three-qubit system, we achieve the preparation of a GHZ state and a W state.

10.
J Clin Med ; 11(15)2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35956163

RESUMEN

Hip arthroscopy is difficult to perform due to the limited arthroscopic view. To solve this problem, the capsulotomy is an important technique. However, the existing capsulotomy approaches were not perfect in the surgical practice. Thus, this study aimed to propose a modified longitudinal capsulotomy by outside-in approach and demonstrate its feasibility and efficacy in arthroscopic femoroplasty and acetabular labrum repair. A retrospective cohort study was performed and twenty-two postoperative patients who underwent hip arthroscopy in our hospital from January 2019 to December 2021 were involved in this study. The patients (14 females and 8 males) had a mean age of 38.26 ± 12.82 years old. All patients were diagnosed cam deformity and labrum tear in the operation and underwent arthroscopic femoroplasty and labrum repair by the modified longitudinal capsulotomy. The mean follow-up time was 10.4 months with a range of 6−12 months. There were no major complications, including infection, neurapraxias, hip instability or revision in any patients. The average mHHS were 74.4 ± 15.2, 78.2 ± 13.7 and 85.7 ± 14.5 in 3 months, 6 months and 12 months after surgery, respectively, which were all better than that before surgery (44.9 ± 8.6) (p < 0.05). The average VAS were 2.8 ± 1.2, 1.5 ± 0.6 and 1.2 ± 0.7 in 3 months, 6 months and 12 months after surgery, respectively, which were all lower than that before surgery (5.5 ± 2.0) (p < 0.05). The modified longitudinal capsulotomy by outside-in approach is proved to be a safe and feasible method for hip arthroscopy considering to the feasibility, efficacy and security. The arthroscopic femoroplasty and labrum repair can be performed conveniently by this approach and the patient reported outcomes after surgery were better that before surgery in short-term follow-up. This new method is promising and suggested to be widely used clinically.

11.
IEEE Trans Cybern ; 52(5): 2750-2762, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33001823

RESUMEN

Robotic grasping ability lags far behind human skills and poses a significant challenge in the robotics research area. According to the grasping part of an object, humans can select the appropriate grasping postures of their fingers. When humans grasp the same part of an object, different poses of the palm will cause them to select different grasping postures. Inspired by these human skills, in this article, we propose new grasping posture prediction networks (GPPNs) with multiple inputs, which acquire information from the object image and the palm pose of the dexterous hand to predict appropriate grasping postures. The GPPNs are further combined with grasping rectangle detection networks (GRDNs) to construct multilevel convolutional neural networks (ML-CNNs). In this study, a force-closure index was designed to analyze the grasping quality, and force-closure grasping postures were generated in the GraspIt! environment. Depth images of objects were captured in the Gazebo environment to construct the dataset for the GPPNs. Herein, we describe simulation experiments conducted in the GraspIt! environment, and present our study of the influences of the image input and the palm pose input on the GPPNs using a variable-controlling approach. In addition, the ML-CNNs were compared with the existing grasp detection methods. The simulation results verify that the ML-CNNs have a high grasping quality. The grasping experiments were implemented on the Shadow hand platform, and the results show that the ML-CNNs can accurately complete grasping of novel objects with good performance.


Asunto(s)
Aprendizaje Profundo , Robótica , Dedos , Mano , Fuerza de la Mano , Humanos , Robótica/métodos
12.
Artículo en Inglés | MEDLINE | ID: mdl-34911000

RESUMEN

The novel core-shell structural zeolitic imidazolate framework-8 @molecularly imprinted polymers were successfully synthesized by surface imprinting technique and used as adsorbents for solid-phase extraction of organophosphorus pesticides. The obtained hybrid composites were characterized by scanning electron microscopy, transmission electron microscopy and Fourier-transform infrared, and their adsorbing and recognition performance were evaluated by binding experiments. The results showed that zeolitic imidazolate framework-8 @molecularly imprinted polymers presented a typically core-shell structure with molecularly imprinted shell (about 50 nm) homogeneously polymerized on the surface of zeolitic imidazolate framework-8 core, and exhibited specific recognition towards organophosphorus pesticides with fast adsorption capacity. The adsorption and desorption conditions including sample loading solvent, sample pH, washing and elution solvent were optimized. Under optimum conditions, the solid-phase extraction based on zeolitic imidazolate framework-8 @molecularly imprinted polymers combined with high liquid chromatography-tandem mass spectrometry method for determining organophosphorus pesticides was established and exhibited good linearity (R2 ≥ 0.9927) in the range of 1-200 µg/L. With spiked at three different concentration levels in agricultural products (cauliflower, radish, pear, muskmelon), the recoveries ranged from 82.5% to 123.0% with relative standard deviations lower than 8.24%. The developed method was sensitive, convenient and efficient. More importantly, this study could provide a promising strategy for designing new adsorbents with extremely fast mass transfer rate for other potential trace contaminants.


Asunto(s)
Estructuras Metalorgánicas/química , Polímeros Impresos Molecularmente/química , Compuestos Organofosforados , Plaguicidas , Extracción en Fase Sólida/métodos , Adsorción , Cromatografía Líquida de Alta Presión , Límite de Detección , Modelos Lineales , Compuestos Organofosforados/análisis , Compuestos Organofosforados/química , Compuestos Organofosforados/aislamiento & purificación , Plaguicidas/análisis , Plaguicidas/química , Plaguicidas/aislamiento & purificación , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
13.
Foods ; 11(16)2022 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-36010453

RESUMEN

A simple and green strategy has been demonstrated for the synthesis of carbon dots (CDs) from mussels. The chemical structure and optical properties of mussels-derived CDs prepared at different reaction temperatures (140, 160, and 180 °C) were evaluated. The average size of synthesized fluorescent CDs decreased from 2.06 to 1.30 nm as reaction temperatures increased from 140 to 180 °C. The fluorescence quantum yield of CDs could reach up to 15.20%. The surface of CDs was rich in functional groups such as -OH, -NH2, and -COOH, providing CDs with good water solubility and biocompatibility. Furthermore, the mussel-derived CDs have been successfully applied in bio-imaging for onion endothelium cells, HepG2 cells, and zebrafish. In addition, CDs could be employed as a biosensor for riboflavin detection. Therefore, mussels are a promising carbon resource for preparing N-doped CDs for bio-imaging and monitoring riboflavin.

14.
Artículo en Inglés | MEDLINE | ID: mdl-35994993

RESUMEN

The core-shell metal-organic framework coated with molecularly imprinted polymers (ZIF-8@MIPs) were successfully synthesized by surface imprinting technique, and applied as adsorbents for solid-phase extraction of strobilurin fungicides. The obtained hybrid complex was characterized in detail, and their adsorbing and recognition performance were evaluated. The results showed that ZIF-8@MIPs presented typically core-shell structure with MIP shell (about 20 nm), and exhibited larger adsorption capacity (102.5 mg g-1) and fast adsorption ability (only 5 min). Under the optimized conditions, a sensitive, efficient and reliable method for determining six strobilurin fungicides in different agricultural products based on ZIF-8@MIPs coupling with high performance liquid chromatography-tandem mass spectrometry was established. This method showed good linearity with correlation coefficients higher than 0.9990. With spiked at three different concentration levels in agricultural products (apple, pear, banana, Chinese cabbage, cabbage, cucumber), the good recoveries (83.5-129.0%) with relative standard deviations from 0.5 to 10.2% were obtained. The limit of detections and the limit of quantifications were 0.01-1.12 ng g-1 and 0.03-3.73 ng g-1, respectively. Those results demonstrated good potential application of ZIF-8@MIPs for enriching and separating trace strobilurin fungicides in agricultural samples.


Asunto(s)
Fungicidas Industriales , Estructuras Metalorgánicas , Impresión Molecular , Adsorción , Impresión Molecular/métodos , Polímeros Impresos Molecularmente , Polímeros/química , Extracción en Fase Sólida/métodos , Estrobilurinas
15.
Natl Sci Rev ; 9(10): nwac190, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36415316

RESUMEN

The realization of automated chemical experiments by robots unveiled the prelude to an artificial intelligence (AI) laboratory. Several AI-based systems or robots with specific chemical skills have been demonstrated, but conducting all-round scientific research remains challenging. Here, we present an all-round AI-Chemist equipped with scientific data intelligence that is capable of performing basic tasks generally required in chemical research. Based on a service platform, the AI-Chemist is able to automatically read the literatures from a cloud database and propose experimental plans accordingly. It can control a mobile robot in-house or online to automatically execute the complete experimental process on 14 workstations, including synthesis, characterization and performance tests. The experimental data can be simultaneously analysed by the computational brain of the AI-Chemist through machine learning and Bayesian optimization, allowing a new hypothesis for the next iteration to be proposed. The competence of the AI-Chemist has been scrutinized by three different chemical tasks. In the future, the more advanced all-round AI-Chemists equipped with scientific data intelligence may cause changes to the landscape of the chemical laboratory.

16.
Am J Sports Med ; 49(4): 1023-1030, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33592149

RESUMEN

BACKGROUND: Three-dimensional computed tomography (3D-CT) is commonly used for the evaluation of cam deformity; however, it does not display the cam border directly. PURPOSE: To compare the efficacy of the best-fit sphere (BFS) method and the alpha angle marking (AAM) method in 3D-CT evaluation for the cam border. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 3. METHODS: Twenty-six cases of cam deformity, confirmed during hip arthroscopy, were included in this study. All patients underwent a CT scan before surgery. Using multiplanar reconstruction, we obtained reformatted CT images of oblique axial, oblique coronal, and radial views. The alpha angle and femoral head-neck offset ratio (hnoR) were measured on the reformatted CT images. The cam area on 3D-CT was displayed in 4 different ways: by importing the markers from the reformatted CT images of the oblique axial view (cam-oa), the oblique coronal view (cam-oc), or the radial view (cam-r) using the AAM method, or by using the BFS method (cam-bfs). The sizes and locations of the displayed cams were compared. RESULTS: All hips in this study had an alpha angle greater than 60° and an hnoR smaller than 0.17. The radial view measured a larger alpha angle and smaller hnoR than the oblique axial and coronal views (P < .05). The areas of cam-oa, cam-oc, cam-r, and cam-bfs were 161.47 ± 27.96, 89.78 ± 19.23, 241.73 ± 34.55, and 329.75 ± 42.73 mm2, respectively, and their medial-to-lateral ranges along the acetabulum (clockface referents) were 12:30 to 03:00, 11:30 to 01:30, 11:30 to 03:00, and 11:00 to 03:30, respectively. Among the 4 displays, cam-bfs had the largest area and medial-to-lateral range (P < .05), and cam-r had the second largest area and range (P < .05). No significant difference in the mean distances from the acetabular rim to the superior border was detected among the 4 displays (P > .05). CONCLUSION: The cam area displayed by the BFS method on 3D-CT was larger than those evaluated by the AAM method. In the reformatted CT, the sizes and locations of cam deformity differed among the oblique axial, oblique coronal, and radial views, with the radial view showing the greatest area.


Asunto(s)
Pinzamiento Femoroacetabular , Estudios de Cohortes , Pinzamiento Femoroacetabular/diagnóstico por imagen , Cabeza Femoral , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/cirugía , Humanos , Tomografía Computarizada por Rayos X
17.
NanoImpact ; 21: 100290, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-35559779

RESUMEN

Fluorescence nanoparticles (FNs) are a type of nano-dots generated during baking process, and their safety on organism is unclear and little is known to their cytotoxicity. In this study, the FNs from instant coffee were purified and characterized. The FNs with an average size about 2.08 nm emitted bright blue fluorescence with lifetime about 2.74 ns. The element and functional groups were analyzed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy, respectively. The results indicated that these FNs were internalized in lysosomes and induced apoptosis of normal rat kidney (NRK) and Caco-2 cells. While, the pan-caspase inhibitor, Z-VAD-FMK didn't decrease the rate of apoptosis and cell death of the FNs-treated NRK and Caco-2 cells. These internalized FNs enlarged lysosomes, decreased lysosomal enzyme degradation activity and increased lysosomal pH value. Partial co-localization of receptor-interacting serine-threonine kinase 3 (RIPK3) to lysosomes in FNs-treated cells was observed, and the amount of RIPK1 and RIPK3 increased after treatment with FNs. The results demonstrated that the FNs from instant coffee induced lysosomal membrane permeabilization and initiated necroptosis.


Asunto(s)
Nanopartículas , Necroptosis , Animales , Células CACO-2 , Muerte Celular , Café/metabolismo , Fluorescencia , Humanos , Lisosomas/metabolismo , Ratas
18.
Int J Biol Macromol ; 167: 415-422, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33278433

RESUMEN

Foodborne nanoparticles have attracted considerable interest due to their distinctive fluorescence and physicochemical properties. The discovery of vinegar carbon dots (VCDs) has drawn our attention to study their effect on human plasma protein. Herein, spectral, constructional, morphological, and enzymatic activity assessments were carried out to investigate the interaction of VCDs with human hemoglobin (HHb). The intrinsic fluorescence of HHb was quenched significantly by the VCDs through a static quenching process. Furthermore, binding constants and important thermodynamic parameters were calculated, the negative enthalpy and entropy changes were accompanied by a negative Gibbs energy, which proposed the binding between VCDs with HHb was spontaneous. Moreover, negative enthalpy and entropy change corroborated the involvement of van der Waals force and hydrogen bonds in the binding process. Results from FTIR, atomic force microscopy and circular dichroism revealed change of HHB after binding with VCDs although their essential morphological features were unaffected. The esterase activity of HHb decreased after VCDs treatment in a dose-dependent manner, which further confirmed the effect of VCDs on HHb. The results offered detailed information about the interaction between VCDs and HHb.


Asunto(s)
Ácido Acético/química , Carbono/química , Fluorescencia , Hemoglobinas/química , Fenómenos Químicos , Dicroismo Circular , Activación Enzimática , Humanos , Microscopía de Fuerza Atómica , Unión Proteica , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Análisis Espectral , Termodinámica
19.
Am J Sports Med ; 48(8): 1826-1836, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32453629

RESUMEN

BACKGROUND: Graft bridging is used in massive rotator cuff tear (MRCT); however, the integration of graft-tendon and graft-bone is still a challenge. HYPOTHESIS: A co-electrospinning nanoscaffold of polycaprolactone (PCL) with an "enthesis-mimicking" (EM) structure could bridge MRCT, facilitate tendon regeneration, and improve graft-bone healing. STUDY DESIGN: Controlled laboratory study. METHODS: First, we analyzed the cytocompatibility of the electrospinning nanoscaffolds, including aligned PCL (aPCL), nonaligned PCL (nPCL), aPCL-collagen I, nPCL-collagen II, and nPCL-nanohydroxyapatite (nHA). Second, for the EM condition, nPCL-collagen II and nPCL-nHA were electrospun layer by layer at one end of the aPCL-collagen I; for the control condition, the nPCL was electrospun on the aPCL. In 40 mature male rats, resection of both the supraspinatus and infraspinatus tendons was performed to create MRCT, and the animals were divided randomly into EM and control groups. In both groups, one end of the layered structure was fixed on the footprint of the rotator cuff, whereas the other end of the layered structure was sutured with the tendon stump. The animals were euthanized for harvesting of tissues for histologic and biomechanical analysis at 4 weeks or 8 weeks postoperatively. RESULTS: All scaffolds showed good cytocompatibility in vitro. The graft-tendon tissue in the EM group had more regularly arranged cells, denser tissue, a significantly higher tendon maturing score, and more birefringence compared with the control group at 8 weeks after operation. Newly formed fibrocartilage could be observed at the graft-bone interface in both groups by 8 weeks, but the EM group had a higher graft-bone healing score and significantly more newly formed fibrocartilage than the control group. An enthesis-like structure with transitional layers was observed in the EM group at 8 weeks. Biomechanically, the values for maximum failure load and stiffness of the tendon-graft-bone complex were significantly higher in the EM group than in the control group at 8 weeks. CONCLUSION: The co-electrospinning nanoscaffold of aPCL-collagen I could be used as a bridging graft to improve early graft-tendon healing for MRCT in a rat model and enhance early enthesis reconstruction in combination with a multilayered structure of nPCL-collagen II and nPCL-nHA. CLINICAL RELEVANCE: We constructed a graft to bridge MRCT, enhance graft-tendon healing and graft-bone healing, and reconstruct the enthesis structure.


Asunto(s)
Nanoestructuras , Lesiones del Manguito de los Rotadores , Manguito de los Rotadores , Andamios del Tejido , Animales , Fenómenos Biomecánicos , Colágeno , Modelos Animales de Enfermedad , Durapatita , Fibrocartílago , Masculino , Poliésteres , Distribución Aleatoria , Ratas , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/cirugía , Cicatrización de Heridas
20.
Am J Sports Med ; 48(11): 2628-2637, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32804547

RESUMEN

BACKGROUND: No study has reported clinical evidence for cartilage change in the glenohumeral joint or the cause of loss in range of motion (ROM) after arthroscopic Bankart repair with remplissage technique (BR). PURPOSE: To investigate the postoperative features of glenohumeral joint cartilage, ROM, and anchor placement for remplissage at a minimum of 2 years of follow-up after BR and to analyze the correlations. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 21 patients who underwent BR received follow-up for a minimum of 2 years. At both preoperative assessment and final follow-up, passive shoulder ROM, Oxford Shoulder Instability Score, Simple Shoulder Test score, and Single Assessment Numerical Evaluation score were assessed. All patients underwent 3.0-T magnetic resonance imaging (MRI) examination at final follow-up. The clinical outcomes, glenohumeral cartilage or Hill-Sachs lesion-related MRI parameters, and their potential correlations were analyzed. RESULTS: The mean follow-up was 55.0 months (range, 24-119 months). Compared with preoperative assessment, all functional scores significantly improved (P < .001). At the final follow-up, a significant ROM loss (>15°) of external rotation (ER) at the side (ER0) was found in 12 patients, among whom 8 patients had significant ROM loss of ER at 90° of abduction as well. Further, 12 patients with decreased ER had significantly higher signal intensity of cartilage on the anterior, middle, and posterior humeral head (anterior, P = .002; middle, P < .001; posterior, P < .001) than 9 patients with normal ER. The ratio of the width of the remplissage anchor to the diameter of the humeral head (w:d ratio) was significantly greater (P = .031) in the decreased ER group than in the normal ER group. Correlation analysis showed that signal intensity on the posterior humeral head and ER0 loss (ΔER0) had a significantly positive correlation (r = 0.516; P = .034), while the w:d ratio and ΔER0 had a significantly positive correlation (r = 0.519; P = .039). CONCLUSION: At a minimum of 2 years of follow-up, patients who underwent BR showed significant clinical improvement compared with preoperative assessment, except for limitations in ER. The glenohumeral cartilage degeneration (higher signal intensity) after BR had a significantly positive correlation with the postoperative ER loss, which was found to be associated with a relatively medial placement of the remplissage anchor.


Asunto(s)
Lesiones de Bankart , Inestabilidad de la Articulación , Luxación del Hombro , Articulación del Hombro , Artroscopía , Cartílago , Estudios de Casos y Controles , Humanos , Rango del Movimiento Articular , Recurrencia , Luxación del Hombro/cirugía , Anclas para Sutura
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