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1.
Opt Express ; 32(5): 8484-8495, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439503

RESUMO

In photonic systems, bilayer or multilayer systems exhibit numerous exciting phenomena induced by twisting. Thus, it is highly desired to explore the twisting effect by engineering the light-matter interactions. Optical torque, an important means in optical micromanipulation, can rotate micro-objects in various ways, enabling a wide range of promising applications. In this study, we present an interesting phenomenon called "pure optical twist" (POT), which emerges when a bilayer structure with specific symmetry is illuminated by counter-propagating lights with opposite spin and/or orbital angular momentum. Remarkably, this leads to zero net optical torque but yet possesses an interesting mechanical effect of bilayer system twisting. The crucial determinant of this phenomenon is the rotational symmetries of each layer, which govern the allowed azimuthal channels of the scattered wave. When the rotational symmetries do not allow these channels to overlap, no resultant torque is observed. Our work will encourage further exploration of the twisting effect through engineered light-matter interactions. This opens up the possibility of creating twisted bilayer systems using optical means, and constructing a stable bilayer optical motor that maintains identical rotation frequencies for both layers.

2.
Bioact Mater ; 36: 272-286, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38496034

RESUMO

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.

3.
Gels ; 10(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38391445

RESUMO

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.

4.
World J Gastroenterol ; 30(2): 115-127, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38312115

RESUMO

Small nucleolar RNAs (snoRNAs) represent a class of non-coding RNAs that play pivotal roles in post-transcriptional RNA processing and modification, thereby contributing significantly to the maintenance of cellular functions related to protein synthesis. SnoRNAs have been discovered to possess the ability to influence cell fate and alter disease progression, holding immense potential in controlling human diseases. It is suggested that the dysregulation of snoRNAs in cancer exhibits differential expression across various cancer types, stages, metastasis, treatment response and/or prognosis in patients. On the other hand, colorectal cancer (CRC), a prevalent malignancy of the digestive system, is characterized by high incidence and mortality rates, ranking as the third most common cancer type. Recent research indicates that snoRNA dysregulation is associated with CRC, as snoRNA expression significantly differs between normal and cancerous conditions. Consequently, assessing snoRNA expression level and function holds promise for the prognosis and diagnosis of CRC. Nevertheless, current comprehension of the potential roles of snoRNAs in CRC remains limited. This review offers a comprehensive survey of the aberrant regulation of snoRNAs in CRC, providing valuable insights into the discovery of novel biomarkers, therapeutic targets, and potential tools for the diagnosis and treatment of CRC and furnishing critical cues for advancing research into CRC and the judicious selection of therapeutic targets.


Assuntos
Neoplasias Colorretais , RNA Nucleolar Pequeno , Humanos , RNA Nucleolar Pequeno/genética , RNA Nucleolar Pequeno/metabolismo , Carcinogênese/genética , Transformação Celular Neoplásica/genética , Prognóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia
5.
Stem Cell Res Ther ; 15(1): 18, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38229196

RESUMO

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.


Assuntos
Micropartículas Derivadas de Células , Exossomos , Células-Tronco Mesenquimais , Ratos , Animais , Exossomos/metabolismo , Cartilagem/metabolismo , Células-Tronco Mesenquimais/metabolismo , Hidrogéis
6.
J Opt Soc Am A Opt Image Sci Vis ; 40(10): 1841-1848, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855539

RESUMO

To address problems such as the lack of accuracy in acquiring depth maps for dynamic fish 3D measurements by usual binocular vision or a time-of-flight (TOF) depth camera, a TOF-assisted binocular vision depth acquisition algorithm is used to obtain high-quality depth maps. The TOF depth energy function is designed to guide the binocular stereo matching process, which improves the correct matching rate of binocular matching in low-texture regions; the TOF and binocular stereo matching confidence weighting functions are designed to achieve the fusion of the two at pixel level to improve the matching quality of fish in the occluded overlapping regions. The experimental results show that the TOF-assisted binocular vision system improves the accuracy of fish size measurement compared to single binocular vision while reducing the measurement error when the fish body has a significant inclination along the depth axis.

7.
Opt Express ; 31(26): 44004-44018, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178482

RESUMO

Evanescent waves, with their high energy density, intricate local momentum, and spatial distribution of spins, have been the subject of extensive recent study. These waves offer promising applications in near-field particle manipulation. Consequently, it becomes imperative to gain a deeper understanding of the impacts of scattering and gradient forces on particles in evanescent waves to enhance and refine the manipulation capabilities. In this study, we employ the multipole expansion theory to present analytical expressions for the scattering and gradient forces exerted on an isotropic sphere of any size and composition in multiple evanescent waves. The investigation of these forces reveals several unusual optomechanical phenomena. It is well known that the scattering force does not exist in counter-propagating homogeneous plane waves. Surprisingly, in multiple pairs of counter-propagating evanescent waves, the scattering force can arise due to the nonzero orbital momentum (OM) density and/or the curl part of the imaginary Poynting momentum (IPM) density. More importantly, it is found that the optical scattering force can be switched on and off by simply tuning the polarization. Furthermore, optical forces typically vary with spatial position in an interference field. However, in the interference field generated by evanescent waves, the gradient force becomes a spatial constant in the propagating plane as the particle's radius increases. This is attributed to the decisive role of the non-interference term of the electromagnetic energy density gradient. Our study establishes a comprehensive and rigorous theoretical foundation, propelling the advancement and optimization of optical manipulation techniques harnessed through multiple evanescent waves. Specifically, these insights hold promise in elevating trapping efficiency through precise control and manipulation of optical scattering and gradient forces, stimulating further explorations.

8.
Opt Express ; 30(12): 20389-20400, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-36224785

RESUMO

Airy beams exhibit intriguing characteristics, such as diffraction-free propagation, self-acceleration, and self-healing, which have aroused great research interest. However, the spatial light modulator that generates Airy beams has problems such as narrow operational bandwidth, high cost, poor phase discretization, and single realization function. In the visible region (λ∼532 nm), we proposed a switchable all-dielectric metasurface for generating transmissive and reflective two-dimensional (2D) Airy beams. The metasurface was mainly composed of titanium dioxide nanopillars and vanadium dioxide substrate. Based on the Pancharatnam-Berry phase principle, a high-efficient Airy beam can be generated by controlling the phase transition of vanadium dioxide and changing the polarization state of the incident light. The optimized optical intensity conversion efficiencies of the transmissive and reflective metasurfaces were as high as 97% and 70%, respectively. In the field of biomedical and applied physics, our designed switchable metasurface is expected to offer the possibility of creating compact optical and photonic platforms for efficient generation and dynamic modulation of optical beams and open up a novel path for the application of high-resolution optical imaging systems.

9.
Am J Sports Med ; 50(10): 2740-2752, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867349

RESUMO

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.


Assuntos
Tendão do Calcâneo , Micropartículas Derivadas de Células , Exossomos , Células-Tronco Mesenquimais , Tendinopatia , Tendão do Calcâneo/patologia , Animais , Micropartículas Derivadas de Células/patologia , Colagenases , Ratos , Tendinopatia/metabolismo
10.
Spine (Phila Pa 1976) ; 47(10): E448-E455, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34524271

RESUMO

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVES: This study compared the function and radiographical outcomes of the patients who underwent C2 dome-like expansive laminoplasty to those C2 expansive open-door laminoplasty for the treatment of OPLL with C2 involved. SUMMARY OF BACKGROUND DATA: There are few comparative studies of these two surgical methods. C2 dome-like and C2 expansive open-door laminoplasty are posterior approaches for posterior longitudinal ligament ossification with C2 level and above. METHODS: This study performed a retrospective cohort analysis of 59 patients with OPLL up to C2 which cause compression symptoms. 31 patients underwent C2 dome-like expansive laminoplasty with C3-7 expansive open-door laminoplasty (Group Dom) and 28 underwent C2-7 expansive open-door laminoplasty (Group Exp). The preoperative and postoperative space available for cord (SAC) of C2 segment, cervical curvature index of C2-7, C2-7 range of motion, Japanese orthopedic association (JOA) score, visual analog scale (VAS) score, and neck disability index (NDI) were used to assess clinical out-comes and statistically analyzed. RESULTS: The cervical curvature index, JOA score, and NDI significantly changed at the final follow-up in two groups with no significant intergroup differences. There were no significant differences in preoperative SAC and VAS between the two groups. At the final follow-up, the SAC of C2/3 in Group Exp was significantly larger than Group Dom, while the VAS and range of motion of Group Dom became significantly better than Group Exp. CONCLUSION: The C2 dome-like expansive laminoplasty can reduce postoperative neck pain more obviously and achieve better cervical curvature. C2 expansive open-door laminoplasty can get more adequate decompression in the spinal canal, which may be recommend to the patients with OPLL occupying more than 50% of the vertebral canal at C2/3, or with developmental spinal stenosis. LEVEL OF EVIDENCE: 3.


Assuntos
Laminoplastia , Ossificação do Ligamento Longitudinal Posterior , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Humanos , Laminoplastia/efeitos adversos , Ligamentos Longitudinais/cirurgia , Ossificação do Ligamento Longitudinal Posterior/diagnóstico por imagem , Ossificação do Ligamento Longitudinal Posterior/etiologia , Ossificação do Ligamento Longitudinal Posterior/cirurgia , Osteogênese , Estudos Retrospectivos , Resultado do Tratamento
11.
Front Cell Dev Biol ; 9: 647166, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900977

RESUMO

Objectives: Repairing articular cartilage damage is challenging. Clinically, tissue engineering technology is used to induce stem cell differentiation and proliferation on biological scaffolds to repair defective joints. However, no ideal biological scaffolds have been identified. This study investigated the effects of amniotic membrane/collagen scaffolds on the differentiation of adipose-derived stem cells (ADSCs) and articular cartilage repair. Methods: Adipose tissue of New Zealand rabbits was excised, and ADSCs were isolated and induced for differentiation. An articular cartilage defect model was constructed to identify the effect of amniotic membrane/collagen scaffolds on cartilage repair. Cartilage formation was analyzed by imaging and toluene blue staining. Knee joint recovery in rabbits was examined using hematoxylin and eosin, toluidine, safranine, and immunohistochemistry at 12 weeks post-operation. Gene expression was examined using ELISA, RT-PCR, Western blotting, and immunofluorescence. Results: The adipose tissue was effectively differentiated into ADSCs, which further differentiated into chondrogenic, osteogenic, and lipogenic lineages after 3 weeks' culture in vitro. Compared with platelet-rich plasmon (PRP) scaffolds, the amniotic membrane scaffolds better promoted the growth and differentiation of ADSCs. Additionally, scaffolds containing the PRP and amniotic membrane efficiently enhanced the osteogenic differentiation of ADSCs. The levels of COL1A1, COL2A1, COL10A1, SOX9, and ACAN in ADSCs + amniotic membrane + PRP group were significantly higher than the other groups both in vitro and in vivo. The Wakitani scores of the ADSC + amniotic membrane + PRP group were lower than that in ADSC + PRP (4.4 ± 0.44**), ADSC + amniotic membrane (2.63 ± 0.38**), and control groups (6.733 ± 0.21) at week 12 post-operation. Osteogenesis in rabbits of the ADSC + amniotic membrane + PRP group was significantly upregulated when compared with other groups. Amniotic membranes significantly promoted the expression of cartilage regeneration-related factors (SOX6, SOX9, RUNX2, NKX3-2, MEF2C, and GATA4). The ADSC + PRP + amniotic membrane group exhibited the highest levels of TGF-ß, PDGF, and FGF while exhibiting the lowest level of IL-1ß, IL6, and TNF-α in articular cavity. Conclusion: Amniotic membrane/collagen combination-based scaffolds promoted the proliferation and cartilage differentiation of ADSCs, and may provide a new treatment paradigm for patients with cartilage injury.

12.
J Biochem Mol Toxicol ; 35(9): e22844, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34250664

RESUMO

Osteoarthritis (OA) is a common joint disease that ultimately causes physical disability and imposes an economic burden on society. Cartilage destruction plays a key role in the development of OA. Vorinostat is an oral histone deacetylase (HDAC) inhibitor and has been used for the treatment of T-cell lymphoma. Previous studies have reported the anti-inflammatory effect of HDAC inhibitors in both in vivo and in vitro models. However, it is unknown whether vorinostat exerts a protective effect in OA. In this study, our results demonstrate that treatment with vorinostat prevents interleukin 1α (IL-1α)-induced reduction of type II collagen at both gene and protein levels. Treatment with vorinostat reduced the IL-1α-induced production of mitochondrial reactive oxygen species (ROS) in T/C-28a2 cells. Additionally, vorinostat rescued the IL-1α-induced decrease in the expression of the collagen type II a1 (Col2a1) gene and the expression of Sry-related HMG box 9 (SOX-9). Importantly, we found that vorinostat inhibited the expression of matrix metalloproteinase-13 (MMP-13), which is responsible for the degradation of type II collagen. Furthermore, vorinostat suppressed the expression of E74-like factor 3 (ELF3), which is a key transcription factor that plays a pivotal role in the IL-1α-induced reduction of type II collagen. Also, the overexpression of ELF3 abolished the protective effects of vorinostat against IL-1α-induced loss of type 2 collagen by inhibiting the expression of SOX-9 whilst increasing the expression of MMP-13. In conclusion, our findings suggest that vorinostat might prevent cartilage destruction by rescuing the reduction of type II collagen, mediated by the suppression of ELF3.


Assuntos
Condrócitos/metabolismo , Colágeno Tipo II/biossíntese , Proteínas de Ligação a DNA/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1alfa/farmacologia , Proteínas Proto-Oncogênicas c-ets/biossíntese , Fatores de Transcrição/biossíntese , Vorinostat/farmacologia , Linhagem Celular , Humanos , Interleucina-1alfa/metabolismo
13.
ACS Appl Mater Interfaces ; 13(29): 33802-33811, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34282616

RESUMO

Antibiotic abuse resulted in the emergence of multidrug-resistant Gram-positive pathogens, which pose a severe threat to public health. It is urgent to develop antibiotic substitutes to kill multidrug-resistant Gram-positive pathogens effectively. Herein, the antibacterial dialdehyde nanocrystalline cellulose (DNC) was prepared and characterized. The antibacterial activity and biosafety of DNC were studied. With the increasing content of aldehyde groups, DNC exhibited high antibacterial activity against Gram-positive pathogens in vitro. DNC3 significantly reduced the amounts of methicillin-resistant Staphylococcus aureus (MRSA) on the skin of infected mice models, which showed low cytotoxicity, excellent skin compatibility, and no acute oral toxicity. DNC exhibited potentials as antibiotic substitutes to fight against multidrug-resistant bacteria, such as ingredients in salves to treat skin infection and other on-skin applications.


Assuntos
Antibacterianos/uso terapêutico , Celulose/análogos & derivados , Nanopartículas/uso terapêutico , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Linhagem Celular , Celulose/química , Celulose/uso terapêutico , Celulose/toxicidade , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Nanopartículas/química , Nanopartículas/toxicidade , Pele/efeitos dos fármacos , Pele/microbiologia , Pele/patologia , Infecções Cutâneas Estafilocócicas/patologia
14.
Orthop J Sports Med ; 9(2): 2325967120982139, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33718499

RESUMO

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.

15.
Cell Transplant ; 28(12): 1709-1720, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31565996

RESUMO

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.


Assuntos
Tecido Adiposo/metabolismo , Cartilagem , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Alicerces Teciduais , Aloenxertos , Animais , Autoenxertos , Cartilagem/lesões , Cartilagem/metabolismo , Cartilagem/patologia , Condrócitos/metabolismo , Condrócitos/patologia , Modelos Animais de Doenças , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Ratos , Ratos Sprague-Dawley
16.
Orthop Surg ; 11(5): 857-863, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31532924

RESUMO

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.


Assuntos
Músculo Esquelético/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Lesões do Manguito Rotador/cirurgia , Traumatismos dos Tendões/cirurgia , Tenodese/métodos , Tenotomia/métodos , Idoso , Artroscopia , Avaliação da Deficiência , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/lesões , Medição da Dor , Estudos Prospectivos
17.
Medicine (Baltimore) ; 98(34): e16837, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31441856

RESUMO

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.


Assuntos
Tendão do Calcâneo/lesões , Alcaptonúria/complicações , Ocronose/complicações , Tendão do Calcâneo/cirurgia , Alcaptonúria/urina , Artroplastia do Joelho , Cartilagem Articular/patologia , Cartilagem Articular/cirurgia , Progressão da Doença , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/patologia , Articulação do Joelho/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea/etiologia , Ruptura Espontânea/cirurgia
18.
J Hazard Mater ; 371: 156-164, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-30849570

RESUMO

Efficient removal of chlorinated volatile organic compounds (CVOCs) has received great attention because of the considerable harm that they cause to the environment and to human health. Developing novel catalysts and exploring the catalytic activation and deconstruction mechanism of CVOCs molecule are always the focus in this field. Here, a set of Sn doped TiO2 catalysts were investigated for the decomposition of dichloromethane (DCM). Rietveld refinement of the XRD patterns showed that Sn ions can uniformly disperse into TiO2 and induce the crystal transition of anatase. Meanwhile, such decorating can induce an increase in specific surface area and affect the surface oxygen vacancy concentration of these samples, which have been demonstrated by N2 adsorption and XPS, respectively. Catalytic performance tests indicated that the Sn0.2Ti0.8O2 has the best activity for DCM decomposition, and a lower CH3Cl selectivity than that of pure TiO2. Computational results suggested the dominant surface (110) of rutile Sn0.2Ti0.8O2 is more beneficial for the adsorption/dissociation of DCM molecule than that of anatase TiO2 (101). That's because the anchoring of DCM to Sn sites and electron enrichment on the surface bridge oxygen atoms of rutile Sn0.2Ti0.8O2 (110) can promote the nucleophilic substitution process for breaking of CCl bonds.

19.
Sci Rep ; 8(1): 17911, 2018 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-30559344

RESUMO

The zone of calcified cartilage (ZCC) is the mineralized region between the hyaline cartilage and subchondral bone and is critical in cartilage repair. A new non-stoichiometric calcium silicate (10% Ca substituted by Mg; CSi-Mg10) has been demonstrated to be highly bioactive in an osteogenic environment in vivo. This study is aimed to systematically evaluate the potential to regenerate osteochondral interface with different amount of Ca-Mg silicate in hydrogel-based scaffolds, and to compare with the scaffolds containing conventional Ca-phosphate biomaterials. Hydrogel-based porous scaffolds combined with 0-6% CSi-Mg10, 6% ß-tricalcium phosphate (ß-TCP) or 6% nanohydroxyapatite (nHAp) were made with three-dimensional (3D) printing. An increase in CSi-Mg10 content is desirable for promoting the hypertrophy and mineralization of chondrocytes, as well as cell proliferation and matrix deposition. Osteogenic and chondrogenic induction were both up-regulated in a dose-dependent manner. In comparison with the scaffolds containing 6% ß-TCP or nHAp, human deep zone chondrocytes (hDZCs) seeded on CSi-Mg10 scaffold of equivalent concentration exhibited higher mineralization. It is noteworthy that the hDZCs in the 6% CSi-Mg10 scaffolds maintained a higher expression of the calcified cartilage zone specific extracellular matrix marker and hypertrophic marker, collagen type X. Immunohistochemical and Alizarin Red staining reconfirmed these findings. The study demonstrated that hydrogel-based hybrid scaffolds containing 6% CSi-Mg10 are particularly desirable for inducing the formation of calcified cartilage.


Assuntos
Compostos de Cálcio/farmacologia , Cartilagem/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Hidrogéis/farmacologia , Magnésio/farmacologia , Regeneração/efeitos dos fármacos , Silicatos/farmacologia , Materiais Biocompatíveis/farmacologia , Fosfatos de Cálcio/farmacologia , Cartilagem/metabolismo , Células Cultivadas , Colágeno Tipo X/metabolismo , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Humanos , Osteogênese/efeitos dos fármacos , Impressão Tridimensional , Engenharia Tecidual/métodos , Alicerces Teciduais
20.
RSC Adv ; 8(38): 21541-21550, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35539939

RESUMO

To understand the roles of pore structures and functional groups on acetone adsorption, activated carbons (ACs) with different properties were obtained by surface modification. XRD, SEM, TEM and nitrogen adsorption were used to identify the structural characteristics of the ACs, while TG-DTA, FTIR, XPS and Boehm titration were applied to analyse the surface chemistries. The microporous surface areas showed a positive linear correlation to the acetone adsorption amounts, and increasing the carboxylic groups could improve the uptake of strongly adsorbed acetone. HNO3 modified AC (AC-N) was found to exhibit an excellent adsorption capacity of 5.49 mmol g-1, which might be attributed to the developed microporous structures and abundant carboxylic groups. The desorption activation energies (E d) of strongly adsorbed acetone on AC-N and AC were both determined to be 81.6 kJ mol-1, indicating the same adsorption sites on different activated carbons, suspected to be carboxylic groups. The possible adsorption mechanism of acetone on carbonaceous surfaces was also proposed.

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