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1.
Sensors (Basel) ; 21(3)2021 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-33530391

RESUMEN

Surface-enhanced Raman spectroscopy (SERS) technology is an attractive method for the prompt and accurate on-site screening of illicit drugs. As portable Raman systems are available for on-site screening, the readiness of SERS technology for sensing applications is predominantly dependent on the accuracy, stability and cost-effectiveness of the SERS strip. An atmospheric-pressure plasma-assisted chemical deposition process that can deposit an even distribution of nanogold particles in a one-step process has been developed. The process was used to print a nanogold film on a paper-based substrate using a HAuCl4 solution precursor. X-ray photoelectron spectroscopy (XPS) analysis demonstrates that the gold has been fully reduced and that subsequent plasma post-treatment decreases the carbon content of the film. Results for cocaine detection using this substrate were compared with two commercial SERS substrates, one based on nanogold on paper and the currently available best commercial SERS substrate based on an Ag pillar structure. A larger number of bands associated with cocaine was detected using the plasma-printed substrate than the commercial substrates across a range of cocaine concentrations from 1 to 5000 ng/mL. A detection limit as low as 1 ng/mL cocaine with high spatial uniformity was demonstrated with the plasma-printed substrate. It is shown that the plasma-printed substrate can be produced at a much lower cost than the price of the commercial substrate.

2.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 45(2): 126-31, 2016 03.
Artículo en Zh | MEDLINE | ID: mdl-27273985

RESUMEN

OBJECTIVE: To fabricate organic-inorganic composite tissue engineering scaffolds for reconstructing calcified cartilage layer based on three-dimensional (3D) printing technique. METHODS: The scaffolds were developed by 3D-printing technique with highly bioactive calcium-magnesium silicate ultrafine particles of 1%, 3% and 5% of mass fraction, in which the organic phases were composed of type I collagen and sodium hyaluronate. The 3D-printed scaffolds were then crosslinked and solidified by alginate and CaCl2 aerosol. The pore size and distribution of inorganic phase were observed with scanning electron microscope (SEM); the mechanical properties were tested with universal material testing machine, and the porosity of scaffolds was also measured. RESULTS: Pore size was approximately (212.3 ± 34.2) µm with a porosity of (48.3 ± 5.9)%, the compressive modulus of the scaffolds was (7.2 ± 1.2) MPa, which was irrelevant to the percentage changes of calcium-magnesium silicate, the compressive modulus was between that of cartilage and subchondral bone. CONCLUSION: The porous scaffolds for calcified cartilage layer have been successfully fabricated, which would be used for multi-layered composite scaffolds in osteochondral injury.


Asunto(s)
Bioimpresión , Cartílago/crecimiento & desarrollo , Impresión Tridimensional , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Ensayo de Materiales , Porosidad
3.
Opt Express ; 22(13): 15530-41, 2014 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-24977811

RESUMEN

A finite element method is applied to study the coupling between a nitrogen vacancy (NV) single photon emitter in nanodiamond and surface plasmons in a silver nanowire embedded in an alumina nanochannel template. We investigate the effective parameters in the coupled system and present detailed optimization for the maximum transmitted power at a selected optical frequency (650 nm). The studied parameters include nanowire length, nanowire diameter, distance between the dipole and the nanowire, orientation of the emitter and refractive index of the surrounding. It is found that the diameter of the nanowire has a strong influence on the propagation of the surface plasmon polaritons and emission power from the bottom and top endings of the nanowire.

4.
Sci Technol Adv Mater ; 15(4): 045004, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27877705

RESUMEN

A novel interfacial structure consisting of long (up to 5 µm), thin (about 300 nm), highly-ordered, free-standing, highly-reproducible aluminum oxide nanobottles and long tubular nanocapsules attached to a rigid, thin (less than 1 µm) nanoporous anodic alumina membrane is fabricated by simple, fast, catalyst-free, environmentally friendly voltage-pulse anodization. A growth mechanism is proposed based on the formation of straight channels in alumina membrane by anodization, followed by neck formation due to a sophisticated voltage control during the process. This process can be used for the fabrication of alumina nanocontainers with highly controllable geometrical size and volume, vitally important for various applications such as material and energy storage, targeted drug and diagnostic agent delivery, controlled drug and active agent release, gene and biomolecule reservoirs, micro-biologically protected platforms, nano-bioreactors, tissue engineering and hydrogen storage.

5.
Sci Technol Adv Mater ; 15(5): 055009, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27877721

RESUMEN

Various morphologies of the vertically-aligned graphene flakes were fabricated on the nanoporous templates treated with metal ions in solutions, as well as coated with a thin gold layer and activated in the low-temperature Ar plasma. The thickness and level of structural defects in the graphene flakes could be effectively controlled by a proper selection of the pre-treatment method. We have also demonstrated that various combinations of the flake thickness and defect levels can be obtained, and the morphology and density of the graphene pattern can be effectively controlled. The result obtained could be of interest for various applications requiring fabrication of large graphene networks with controllable properties.

6.
Stem Cell Res Ther ; 15(1): 18, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38229196

RESUMEN

BACKGROUND: Extracellular vesicles (EVs) derived from mesenchymal stromal cells (MSCs) offer promising prospects for stimulating cartilage regeneration. The different formation mechanisms suggest that exosomes and ectosomes possess different biological functions. However, little attention has been paid to the differential effects of EV subsets on cartilage regeneration. METHODS: Our study compared the effects of the two EVs isolated from adipose-derived MSCs (ASCs) on chondrocytes and bone marrow-derived MSCs (BMSCs) in vitro. Additionally, we loaded the two EVs into type I collagen hydrogels to optimize their application for the treatment of osteochondral defects in vivo. RESULTS: In vitro experiments demonstrate that ASC-derived exosomes (ASC-Exos) significantly promoted the proliferation and migration of both cells more effectively than ASC-derived ectosomes (ASC-Ectos). Furthermore, ASC-Exos facilitated a stronger differentiation of BMSCs into chondrogenic cells than ASC-Ectos, but both inhibited chondrocyte apoptosis to a similar extent. In the osteochondral defect model of rats, ASC-Exos promoted cartilage regeneration in situ better than ASC-Ectos. At 8 weeks, the hydrogel containing exosomes group (Gel + Exo group) had higher macroscopic and histological scores, a higher value of trabecular bone volume fraction (BV/TV), a lower value of trabecular thickness (Tb.Sp), and a better remodeling of extracellular matrix than the hydrogel containing ectosomes group (Gel + Ecto group). At 4 and 8 weeks, the expression of CD206 and Arginase-1 in the Gel + Exo group was significantly higher than that in the Gel + Ecto group. CONCLUSION: Our findings indicate that administering ASC-Exos may be a more effective EV strategy for cartilage regeneration than the administration of ASC-Ectos.


Asunto(s)
Micropartículas Derivadas de Células , Exosomas , Células Madre Mesenquimatosas , Ratas , Animales , Exosomas/metabolismo , Cartílago/metabolismo , Células Madre Mesenquimatosas/metabolismo , Hidrogeles
7.
Gels ; 10(2)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38391445

RESUMEN

Meniscus tissue engineering (MTE) has emerged as a promising strategy for meniscus repair and regeneration. As versatile platforms, hydrogels have gained significant attention in this field, as they possess tunable properties that allow them to mimic native extracellular matrices and provide a suitable microenvironment. Additionally, hydrogels can be minimally invasively injected and can be adjusted to match the shape of the implant site. They can conveniently and effectively deliver bioactive additives and demonstrate good compatibility with other functional materials. These inherent qualities have made hydrogel a promising candidate for therapeutic approaches in meniscus repair and regeneration. This article provides a comprehensive review of the advancements made in the research on hydrogel application for meniscus tissue engineering. Firstly, the biomaterials and crosslinking strategies used in the formation of hydrogels are summarized and analyzed. Subsequently, the role of therapeutic additives, including cells, growth factors, and other active products, in facilitating meniscus repair and regeneration is thoroughly discussed. Furthermore, we summarize the key issues for designing hydrogels used in MTE. Finally, we conclude with the current challenges encountered by hydrogel applications and suggest potential solutions for addressing these challenges in the field of MTE. We hope this review provides a resource for researchers and practitioners interested in this field, thereby facilitating the exploration of new design possibilities.

8.
Nat Commun ; 15(1): 2651, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38531881

RESUMEN

Despite orientationally variant tears of the meniscus, suture repair is the current clinical gold treatment. However, inaccessible tears in company with re-tears susceptibility remain unresolved. To extend meniscal repair tools from the perspective of adhesion and regeneration, we design a dual functional biologic-released bioadhesive (S-PIL10) comprised of methacrylated silk fibroin crosslinked with phenylboronic acid-ionic liquid loading with growth factor TGF-ß1, which integrates chemo-mechanical restoration with inner meniscal regeneration. Supramolecular interactions of ß-sheets and hydrogen bonds richened by phenylboronic acid-ionic liquid (PIL) result in enhanced wet adhesion, swelling resistance, and anti-fatigue capabilities, compared to neat silk fibroin gel. Besides, elimination of reactive oxygen species (ROS) by S-PIL10 further fortifies localized meniscus tear repair by affecting inflammatory microenvironment with dynamic borate ester bonds, and S-PIL10 continuously releases TGF-ß1 for cell recruitment and bridging of defect edge. In vivo rabbit models functionally evidence the seamless and dense reconstruction of torn meniscus, verifying that the concept of meniscus adhesive is feasible and providing a promising revolutionary strategy for preclinical research to repair meniscus tears.


Asunto(s)
Ácidos Borónicos , Fibroínas , Líquidos Iónicos , Menisco , Animales , Conejos , Hidrogeles , Factor de Crecimiento Transformador beta1
9.
Bioact Mater ; 36: 272-286, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38496034

RESUMEN

Nanoliposomes have a broad range of applications in the treatment of autoimmune inflammatory diseases because of their ability to considerably enhance drug transport. For their clinical application, nanoliposomes must be able to realize on-demand release of drugs at disease sites to maximize drug-delivery efficacy and minimize side effects. Therefore, responsive drug-release strategies for inflammation treatment have been explored; however, no specific design has been realized for a responsive drug-delivery system based on pyroptosis-related inflammation. Herein, we report a pioneering strategy for self-adaptive pyroptosis-responsive liposomes (R8-cardiolipin-containing nanoliposomes encapsulating dimethyl fumarate, RC-NL@DMF) that precisely release encapsulated anti-pyroptotic drugs into pyroptotic cells. The activated key pyroptotic protein, the N-terminal domain of gasdermin E, selectively integrates with the cardiolipin of liposomes, thus forming pores for controlled drug release, pyroptosis, and inflammation inhibition. Therefore, RC-NL@DMF exhibited effective therapeutic efficacies to alleviate autoimmune inflammatory damages in zymosan-induced arthritis mice and dextran sulfate sodium-induced inflammatory bowel disease mice. Our novel approach holds great promise for self-adaptive pyroptosis-responsive on-demand drug delivery, suppressing pyroptosis and treating autoimmune inflammatory diseases.

10.
Small ; 9(23): 3993-9, 2013 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-23813883

RESUMEN

Molecular doping and detection are at the forefront of graphene research, a topic of great interest in physical and materials science. Molecules adsorb strongly on graphene, leading to a change in electrical conductivity at room temperature. However, a common impediment for practical applications reported by all studies to date is the excessively slow rate of desorption of important reactive gases such as ammonia and nitrogen dioxide. Annealing at high temperatures, or exposure to strong ultraviolet light under vacuum, is employed to facilitate desorption of these gases. In this article, the molecules adsorbed on graphene nanoflakes and on chemically derived graphene-nanomesh flakes are displaced rapidly at room temperature in air by the use of gaseous polar molecules such as water and ethanol. The mechanism for desorption is proposed to arise from the electrostatic forces exerted by the polar molecules, which decouples the overlap between substrate defect states, molecule states, and graphene states near the Fermi level. Using chemiresistors prepared from water-based dispersions of single-layer graphene on mesoporous alumina membranes, the study further shows that the edges of the graphene flakes (showing p-type responses to NO2 and NH3) and the edges of graphene nanomesh structures (showing n-type responses to NO2 and NH3) have enhanced sensitivity. The measured responses towards gases are comparable to or better than those which have been obtained using devices that are more sophisticated. The higher sensitivity and rapid regeneration of the sensor at room temperature provides a clear advancement towards practical molecule detection using graphene-based materials.


Asunto(s)
Grafito/química , Nanotecnología/métodos , Temperatura
11.
Am J Sports Med ; 50(10): 2740-2752, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35867349

RESUMEN

BACKGROUND: Extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) have gained momentum as a treatment for tendinopathy. Multiple studies have demonstrated significant differences in cargo composition between the 2 subtypes of MSC-EVs (ie, exosomes and ectosomes), which may result in different therapeutic effects. However, the effects of the 2 EV subtypes on tendinopathy have not yet been compared. PURPOSE: To compare the effects of adipose stem cell-derived exosomes (ASC-Exos) and ectosomes (ASC-Ectos) on Achilles tendinopathy. STUDY DESIGN: Controlled laboratory study. METHODS: Rats were administered collagenase injections to generate a model of Achilles tendinopathy. A week later, 36 rats were randomly assigned to 3 groups. In each group, Achilles tendons were injected with equal volumes of ASC-Exos, ASC-Ectos, or saline (12 legs/group). The healing outcomes were evaluated by magnetic resonance imaging, histology, immunohistochemistry, transmission electron microscopy, and biomechanical testing at 3 and 5 weeks after collagenase injection. RESULTS: At 3 and 5 weeks, the ASC-Exo group had better histological scores (P = .0036 and P = .0276, respectively), a lower fibril density (P < .0001 and P = .0310, respectively), and a larger collagen diameter (P = .0052 and P < .0001, respectively) than the ASC-Ecto group. At 5 weeks, the expression of collagen type 1 and CD206 in the ASC-Exo group was significantly higher than that in the ASC-Ecto group (P = .0025 and P = .0010, respectively). Regarding biomechanical testing, the ASC-Exo group showed higher failure load (P = .0005), tensile stress (P < .0001), and elastic modulus (P < .0001) than the ASC-Ecto group. CONCLUSION: ASC-Exos had more beneficial effects on tendon repair than ASC-Ectos in a rat model of Achilles tendinopathy. CLINICAL RELEVANCE: Administration of ASC-EVs may have the potential to treat Achilles tendinopathy, and delivery of ASC-Exos could provide additional benefits. It is necessary to compare the healing responses caused by different EV subtypes to further understand their effects on tendinopathy and to aid clinical decision making.


Asunto(s)
Tendón Calcáneo , Micropartículas Derivadas de Células , Exosomas , Células Madre Mesenquimatosas , Tendinopatía , Tendón Calcáneo/patología , Animales , Micropartículas Derivadas de Células/patología , Colagenasas , Ratas , Tendinopatía/metabolismo
12.
Front Surg ; 8: 826682, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35141272

RESUMEN

PURPOSE: To explore the risk factors of acute respiratory distress syndrome (ARDS) secondary to thoracic trauma and the therapeutic effect of protective lung ventilation in patients with acute respiratory distress syndrome complicated with thoracic trauma. METHODS: We collected 206 patients with thoracic trauma admitted to our hospital from September 2017 to March 2021, counted the incidence of ARDS and analyzed the risk factors of ARDS. To observe the clinical efficacy of the application of lung-protective ventilation therapy in patients with thoracic trauma combined with ARDS. RESULTS: Among 206 patients with thoracic trauma, there were 82 cases of combined ARDS, and its incidence was 39.81%. The 82 patients with ARDS were randomly divided into the control group and the observation group with 42 cases each, and different ventilation methods were used for treatment. The results showed that the mechanical ventilation time (MVT) was shorter in the observation group than in the control group, and the incidence of ventilator-associated lung injury (VALI) and case fatality rate (CFR) were lower than those in the control group (P < 0.05). Arterial partial pressure of oxygen (Pa02), arterial blood carbon dioxide partial pressure (PaCO2), and Oxygenation index (arterial partial pressure of oxygen/Fraction of inspiration O2, PaO2/FiO2) were significantly improved better in both groups after treatment; compared with the control group, patients in the observation group had higher Pa02 levels and lower PaCO2 levels at 8 h and 24 h after ventilation (P < 0.05). Multivariate analysis revealed that blunt trauma, massive blood transfusion, procalcitonin (PCT) level, tumor necrosis factor-α (TNF-α) level, and acute physiology and chronic health score (APACHE II) were all risk factors for Thoracic trauma with ARDS. CONCLUSION: Risk factors for the development of ARDS after thoracic trauma are blunt injuries, massive blood transfusion, high PCT and TNF-α levels, and high APACHE II scores, which can be given active interventions in the early stage of clinical practice to improve patient prognosis. The use of protective lung ventilation therapy can improve the clinical outcome of patients with thoracic trauma combined with ARDS, which is important for improving the ventilation effect and respiratory function of patients.

13.
Orthop J Sports Med ; 9(2): 2325967120982139, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33718499

RESUMEN

BACKGROUND: Matrix-associated autologous chondrocyte implantation (MACI) has been proven to provide favorable short-term results for chondral defects in knees. However, it remains unclear whether the clinical benefits of MACI persist in the longer term. PURPOSE: The purpose of this prospective study was to evaluate the clinical and radiological outcomes, at short- and midterm follow-up, for patients undergoing MACI for focal chondral defects of the knee. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 30 consecutive patients (31 knees) were treated using MACI between October 2010 and March 2018. There were 24 male patients and 6 female patients with an average age of 26 years (range, 12-48 years). The areas of the cartilage defect were consistently >2 cm2. All patients underwent MACI for a focal chondral defect of the femoral condyles or trochlea in the knee. These patients had been evaluated for up to 5 years, with an average follow-up of 44 months (range, 6-60 months) postoperatively.The International Knee Documentation Committee (IKDC) score, Lysholm score, and magnetic resonance imaging (MRI) with T2 mapping were used to assess the outcomes. RESULTS: No patients were lost to follow-up. Mean IKDC scores improved from 58.6 (range, 40.2-80.5) to 79.1 (range, 39.1-94.3) at 12 months and up to 88.4 (range, 83.9-100) at 5 years; mean Lysholm scores improved from 67.3 (range, 46-95) to 90.6 (range, 71-100) at 12 months and up to 95.9 (range, 85-100) at 5 years. The MRI with T2 mapping value of the transplanted area was evaluated for 21 knees, which revealed no differences compared with the normal area at 12 months postoperatively. CONCLUSION: From the first year onward, the clinical outcome scores and MRI with T2 mapping values showed continuous and marked improvement, suggesting that MACI is a valid option for localized cartilage defects in the knee.

14.
Sci Total Environ ; 698: 134175, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31518786

RESUMEN

Although jarosite and visible light are important factors for the formation of acid mine drainage (AMD), the effects of combined jarosite and visible light on chalcopyrite biodissolution have not been explored until now. In order to fill this knowledge gap, the combined effects of jarosite and visible light on chalcopyrite dissolution mediated by Acidithiobacillus ferrooxidans were investigated. The results indicated that jarosite and visible light could significantly accelerate chalcopyrite biodissolution, thus releasing more copper ions, iron ions and producing more acid. This in turn suggests enhanced generation of AMD under these conditions. Biodissolution results, mineral surface morphology, mineralogical phase and elemental composition analyses revealed that the promotion of chalcopyrite dissolution by additional jarosite and visible light was mainly attributed to the acceleration of ferric iron/ferrous iron cycling and the inhibition of the formation of a passivation layer (jarosite and Sn2-/S0) on the surface of chalcopyrite. This study provides a better understanding of the effects of jarosite and visible light on chalcopyrite biodissolution. In the future, the influences of jarosite and visible light on chalcopyrite dissolution should be considered in AMD evaluation to ensure reliability.


Asunto(s)
Acidithiobacillus/metabolismo , Biodegradación Ambiental , Cobre/química , Compuestos Férricos/química , Sulfatos/química , Luz
15.
Nanotechnology ; 20(6): 065706, 2009 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-19417400

RESUMEN

Free standing, nanoporous alumina templates were fabricated as transmission masks from aluminium using a two-step anodization process followed by acid etching. The resulting membrane comprises self-ordered, periodic arrays of non-connecting circular channels which can be prepared with pore diameters <100 nm and with minimal occlusion. Aspect ratios greater than 300:1 were measured directly using electron transmission and the channels were shown to be highly aligned (angular) over membrane thicknesses of tens of microns. Also evident is some local order associated with both azimuthal and angular domain structure giving rise to local channel tilt which has not previously been reported. Transmission electron microscopy has been shown to be an important characterization tool for these nanomasks as the channels are transparent to electrons, providing a means of directly measuring their thickness and aspect ratio. Expressions for determining their thickness and aspect ratio are also presented and evaluated in this work. These membranes are well suited for use as nanotemplates in transmission lithography applications including ion implantation and ion or electron beam collimation.

16.
World J Clin Cases ; 7(16): 2134-2142, 2019 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-31531309

RESUMEN

It has been found that obese people have a higher proportion in suffering from osteoarthritis (OA), not only in the weight-bearing joints like knee and hip joints, even in non-weight-bearing joints such as hand joints. One of the reasons is because the large amount of adipose tissue secretes some factors, which can promote the occurrence of arthritis. As an important structure of the knee joint, the infrapatellar fat pad (IPFP) is actually a piece of adipose tissue. The aim of this review is to offer a comprehensive view of the anatomy and physiological characteristics of IPFP and its relationship with the pathological process of OA, indicating the important function of IPFP in OA. At the same time, with the development of adipose derived stem cells in the treatment of OA, owing to its special advantages, the IPFP is becoming a kind of important, minimally invasive fat stem cell source, providing a new approach for the treatment of OA. We hope that this review will offer an overview of all published data regarding the IPFP and will indicate novel directions for future research.

17.
Cell Transplant ; 28(12): 1709-1720, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31565996

RESUMEN

Osteoarthritis (OA) poses a tough challenge worldwide. Adipose-derived stem cells (ASCs) have been proved to play a promising role in cartilage repair. However, enzymatic digestion, ex vivo culture and expansion, with significant senescence and decline in multipotency, limit their application. The present study was designed to obtain micro-fragmented adipose tissue (MFAT) through gentle mechanical force and determine the effect of this stem cell-based natural scaffold on repair of full-thickness cartilage defects. In this study, ASCs sprouted from MFAT were characterized by multi-differentiation induction and flow cytometry. Scratch and transwell migration assays were operated to determine whether MFAT could promote migration of chondrocytes in vitro. In a rat model, cartilage defects were created on the femoral groove and treated with intra-articular injection of MFAT or PBS for 6 weeks and 12 weeks (n = 12). At the time points, the degree of cartilage repair was evaluated by histological staining, immunohistochemistry and scoring, respectively. Two unoperated age-matched animals served as native controls. ASCs derived from MFAT possessed properties to differentiate into adipocytes, osteocytes and chondrocytes, with expression of mesenchymal stem cell markers (CD29, 44, 90) and no expression of hematopoietic markers (CD31, 34, 45). In addition, MFAT could significantly promote migration of chondrocytes. MFAT-treated defects showed improved macroscopic appearance and histological evaluation compared with PBS-treated defects at both time points. After 12 weeks of treatment, MFAT-treated defects displayed regular surface, high amount of hyaline cartilage, intact subchondral bone reconstruction and corresponding formation of type I, II, and VI collagen, which resembled the normal cartilage. This study demonstrates the efficacy of MFAT on cartilage repair in an animal model for the first time, and the utility of MFAT as a ready-to-use therapeutic alternative to traditional stem cell therapy.


Asunto(s)
Tejido Adiposo/metabolismo , Cartílago , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Andamios del Tejido , Aloinjertos , Animales , Autoinjertos , Cartílago/lesiones , Cartílago/metabolismo , Cartílago/patología , Condrocitos/metabolismo , Condrocitos/patología , Modelos Animales de Enfermedad , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Ratas , Ratas Sprague-Dawley
18.
Medicine (Baltimore) ; 98(34): e16837, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31441856

RESUMEN

INTRODUCTION: Alkaptonuria (AKU) is a rare disease caused by deficiency of homogentisate 1,2-dioxygenase which results in deposition of homogentisic acid (HGA). Ochronotic arthritis, the deposition of excess oxidized HGA in the connective tissues, causes pigmentation and degeneration of the joint tissues ultimately resulting in chronic inflammation and osteoarthritis. The ochronotic arthritis has similar clinical features with osteoarthritis. There is currently no specific treatment for AKU and management is usually symptomatic. In severe cases, total joint arthroplasty is the major treatment approaches. It is rarely reported in China. PATIENT CONCERNS: Here we reported a case of a patient with bilateral knee pain for more than 1 year. He complained of a 20-year history of chronic, nonspecific low back pain and stiffness. His urine was black since he was a child. Six years after the knee surgery, his Achilles tendon ruptured. DIAGNOSIS: Specific radiographic and magnetic resonance imaging manifestations were observed. Darkly pigmented full-thickness cartilage and subchondral bone were found during the operation. Histological investigation also manifested dark stains in meniscus and synovial tissues. Black-denatured tendon tissue was also found during the operation. The patient was diagnosed as AKU. INTERVENTIONS: Total knee arthroplasty and Achilles tendon repair were operated separately after the disease was diagnosed. OUTCOMES: The patient recovered very well after the second surgery. He returned to full activities, described no knee pain, and presented to the clinic walking without any aid. Physical examination revealed 0 to 20 of plantar flexion and 0 to 15 of dorsiflexion of the ankle. CONCLUSIONS: Ochronosis is a very rare disease in Asia. This paper supplies new information for study of this disease. The mechanism is still unknown right now. Further studies will be necessary.


Asunto(s)
Tendón Calcáneo/lesiones , Alcaptonuria/complicaciones , Ocronosis/complicaciones , Tendón Calcáneo/cirugía , Alcaptonuria/orina , Artroplastia de Reemplazo de Rodilla , Cartílago Articular/patología , Cartílago Articular/cirugía , Progresión de la Enfermedad , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Rotura Espontánea/etiología , Rotura Espontánea/cirugía
19.
Orthop Surg ; 11(5): 857-863, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31532924

RESUMEN

OBJECTIVE: To compare the clinical and radiological outcomes of patients who underwent rotator cuff repair (RCR) concomitant with long head of the biceps tendon (LHBT) tenotomy or subpectoral mini-open tenodesis. METHODS: Prospectively collected data was reviewed on 154 patients, who underwent a LHBT procedure (tenotomy or tenodesis) concomitant with RCR between January 2010 and January 2017. The exclusion criteria were irreparable massive rotator cuff tear, rotator cuff partial tear, subscapular tendon tear, glenohumeral arthritis, and prior shoulder surgery. The two patient groups are as follows: RCR + Tenotomy (Group A) and RCR + Subpectoral mini-open tenodesis (Group B). The visual analog scale (VAS) for pain, Constant Score scale, American Shoulder and Elbow Surgeons (ASES) scores, and the Disabilities of the Arm, Shoulder and Hand (DASH) scores preoperatively and 1 month, 3 months, 6 months, 1 year postoperatively and the latest out-patient clinic were compared between the two groups. RESULTS: Ninety-two patients in Group A and 62 patients in Group B completed the follow-up, with a median follow-up time of 27 and 42 months respectively. At the final follow-up, the VAS, Constant, ASES, and DASH scores in Group A were 0.1 ± 0.2, 87.0 ± 12.8, 96.4 ± 4.3 and 6.6 ± 4.8 respectively, and the VAS, Constant, ASES, and DASH scores in Group B were 0.1 ± 0.3, 92.5 ± 3.9, 96.3 ± 3.6 and 2.9 ± 1.3 respectively. Clinical evaluation scales showed satisfactory results in both groups, and there were no statistically significant differences between the two groups at the same follow-up time. Popeye sign was detected in one case of Group A (1.1%) and in one case of Group B (1.6%, P > 0.05). CONCLUSION: Both tenotomy and subpectoral mini-open tenodesis are effective for concomitant lesions of the LHBT in patients with reparable rotator cuff tears, and subpectoral mini-open tenodesis of the LHBT does not provide any significant clinical or functional improvement than isolated tenotomy.


Asunto(s)
Músculo Esquelético/cirugía , Procedimientos de Cirugía Plástica/métodos , Lesiones del Manguito de los Rotadores/cirugía , Traumatismos de los Tendones/cirugía , Tenodesis/métodos , Tenotomía/métodos , Anciano , Artroscopía , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/lesiones , Dimensión del Dolor , Estudios Prospectivos
20.
Adv Mater ; 30(2)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29152907

RESUMEN

Increasingly intricate in their composition and structural organization, hierarchical multicomponent metamaterials with nonlinear spatially reconfigurable functionalities challenge the intrinsic constraints of natural materials, revealing tremendous potential for the advancement of biochemistry, nanophotonics, and medicine. Recent breakthroughs in high-resolution nanofabrication utilizing ultranarrow, precisely controlled ion or laser beams have enabled assembly of architectures of unprecedented structural and functional complexity, yet costly, time- and energy-consuming high-resolution sequential techniques do not operate effectively at industry-required scale. Inspired by the fictional Baron Munchausen's fruitless attempt to pull himself up, it is demonstrated that metamaterials can undergo intrinsically driven self-assembly, metaphorically pulling themselves up into existence. These internal drivers hold a key to unlocking the potential of metamaterials and mapping a new direction for the large-area, cost-efficient self-organized fabrication of practical devices. A systematic exploration of these efforts is presently missing, and the driving forces governing the intrinsically driven self-assembly are yet to be fully understood. Here, recent progress in the self-organized formation and self-propelled growth of complex hierarchical multicomponent metamaterials is reviewed, with emphasis on key principles, salient features, and potential limitations of this family of approaches. Special stress is placed on self-assembly driven by plasma, current in liquid, ultrasonic, and similar highly energetic effects, which enable self-directed formation of metamaterials with unique properties and structures.

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