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2.
Adv Sci (Weinh) ; : e2307804, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837887

RESUMO

RNA splicing is crucial in the multilayer regulatory networks for gene expression, making functional interactions with DNA- and other RNA-processing machineries in the nucleus. However, these established couplings are all major spliceosome-related; whether the minor spliceosome is involved remains unclear. Here, through affinity purification using Drosophila lysates, an interaction is identified between the minor spliceosomal 65K/RNPC3 and ANKRD11, a cofactor of histone deacetylase 3 (HDAC3). Using a CRISPR/Cas9 system, Deletion strains are constructed and found that both Dm65KΔ/Δ and Dmankrd11Δ/Δ mutants have reduced histone deacetylation at Lys9 of histone H3 (H3K9) and Lys5 of histone H4 (H4K5) in their heads, exhibiting various neural-related defects. The 65K-ANKRD11 interaction is also conserved in human cells, and the HsANKRD11 middle-uncharacterized domain mediates Hs65K association with HDAC3. Cleavage under targets and tagmentation (CUT&Tag) assays revealed that HsANKRD11 is a bridging factor, which facilitates the synergistic common chromatin-binding of HDAC3 and Hs65K. Knockdown (KD) of HsANKRD11 simultaneously decreased their common binding, resulting in reduced deacetylation of nearby H3K9. Ultimately, this study demonstrates that expression changes of many genes caused by HsANKRD11-KD are due to the decreased common chromatin-binding of HDAC3 and Hs65K and subsequently reduced deacetylation of H3K9, illustrating a novel and conserved coupling mechanism that links the histone deacetylation with minor spliceosome for the regulation of gene expression.

3.
Micromachines (Basel) ; 15(5)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38793129

RESUMO

A multi-layer stacked Dynamic Random Access Memory (DRAM) platform is introduced to address the memory wall issue. This platform features high-density vertical interconnects established between DRAM units for high-capacity memory and logic units for computation, utilizing Wafer-on-Wafer (WoW) hybrid bonding and mini Through-Silicon Via (TSV) technologies. This 3DIC architecture includes commercial DRAM, logic, and 3DIC manufacturing processes. Their design documents typically come from different foundries, presenting challenges for signal integrity design and analysis. This paper establishes a lumped circuit based on 3DIC physical structure and calculates all values of the lumped elements in the circuit model with the transmission line model. A Cross-Process Signal Integrity Analysis (CPSIA) method is introduced, which integrates three different manufacturing processes by modeling vertical stacking cells and connecting DRAM and logic netlists in one simulation environment. In combination with the dedicated buffer driving method, the CPSIA method is used to analyze 3DIC impacts. Simulation results show that the timing uncertainty introduced by 3DIC crosstalk ranges from 31 ps to 62 ps. This analysis result explains the stable slight variation in the maximum frequency observed in vertically stacked memory arrays from different DRAM layers in the physical testing results, demonstrating the effectiveness of this CPSIA method.

4.
Stem Cell Res Ther ; 15(1): 91, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539224

RESUMO

Musculoskeletal disorders are the leading causes of physical disabilities worldwide. The poor self-repair capacity of musculoskeletal tissues and the absence of effective therapies have driven the development of novel bioengineering-based therapeutic approaches. Adipose-derived stem cell (ADSC)-based therapies are being explored as new regenerative strategies for the repair and regeneration of bone, cartilage, and tendon owing to the accessibility, multipotency, and active paracrine activity of ADSCs. In this review, recent advances in ADSCs and their optimization strategies, including ADSC-derived exosomes (ADSC-Exos), biomaterials, and genetic modifications, are summarized. Furthermore, the preclinical and clinical applications of ADSCs and ADSC-Exos, either alone or in combination with growth factors or biomaterials or in genetically modified forms, for bone, cartilage, and tendon regeneration are reviewed. ADSC-based optimization strategies hold promise for the management of multiple types of musculoskeletal injuries. The timely summary and highlights provided here could offer guidance for further investigations to accelerate the development and clinical application of ADSC-based therapies in musculoskeletal regeneration.


Assuntos
Tecido Adiposo , Exossomos , Tecido Adiposo/metabolismo , Adipócitos , Regeneração , Materiais Biocompatíveis , Exossomos/metabolismo , Células-Tronco/metabolismo
5.
Cell Death Discov ; 9(1): 253, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37468464

RESUMO

BACKGROUND: Circular RNAs (circRNAs) and N6-methyladenosine (m6A) have been shown to play an increasingly critical role in the development of different cancers. However, there is limited evidence on how circRNAs and m6A interact to affect the radiosensitivity of cervical cancer (CC). This study provides a mechanistic understanding of the novel m6A-regulated circRNF13 in enhancing radioresistance in CC. METHODS: Differentially expressed circRNAs were identified from radiosensitive and radioresistant CC tissues. Meanwhile, these circRNAs were subjected to methylated RNA immunoprecipitation (Me-RIP). Finally, the effects of these circRNAs on radiosensitivity were characterized. RESULTS: CircRNF13 was poorly expressed in CC patients that were sensitive to concurrent radiochemotherapy. Experiments conducted both in vitro and in vivo confirmed that the knockdown of circRNF13 potentiated the radiosensitivity of CC cells. Further mechanistic studies revealed that METTL3/YTHDF2 promoted the degradation of circRNF13 and subsequently affected the stability of CXC motif chemokine ligand 1 (CXCL1), ultimately enhancing the radiosensitivity of CC cells. CONCLUSION: This study identified circRNF13 as a novel m6A-modified circRNA and validated the METTL3/YTHDF2/circRNF13/CXCL1 axis as a potential target for CC radiotherapy.

6.
J Control Release ; 357: 319-332, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37028453

RESUMO

Patients with peripheral nerve injuries would highly likely suffer from chronic neuropathic pain even after surgical intervention. The primary reasons for this involve sustained neuroinflammatory and dysfunctional changes in the nervous system after the nerve injury. We previously reported an injectable boronic ester-based hydrogel with inherent antioxidative and nerve protective properties. Herein, we first explored the anti-neuroinflammatory effects of Curcumin on primary sensory neurons and activated macrophages in vitro. Next, we incorporated thiolated Curcumin-Pluronic F-127 micelles (Cur-M) into our boronic ester-based hydrogel to develop an injectable hydrogel that serves as sustained curcumin release system (Gel-Cur-M). By orthotopically injecting the Gel-Cur-M to sciatic nerves of mice with chronic constriction injuries, we found that the bioactive components could remain on the nerves for at least 21 days. In addition, the Gel-Cur-M exhibited superior functions compared to Gel and Cur-M alone, which includes ameliorating hyperalgesia while simultaneously improving locomotor and muscular functions after the nerve injury. This could stem from in situ anti-inflammation, antioxidation, and nerve protection. Furthermore, the Gel-Cur-M also showed extended beneficial effects for preventing the overexpression of TRPV1 as well as microglial activation in the lumbar dorsal root ganglion and spinal cord, respectively, which also contributed to its analgesic effects. The underlying mechanism may involve the suppression of CC chemokine ligand-2 and colony-stimulating factor-1 in the injured sensory neurons. Overall, this study suggests that orthotopic injection of the Gel-Cur-M is a promising therapeutic strategy that especially benefits patients with peripheral neuropathy who require surgical interventions.


Assuntos
Curcumina , Neuralgia , Camundongos , Animais , Hidrogéis , Portadores de Fármacos , Micelas , Neuralgia/tratamento farmacológico
7.
Sensors (Basel) ; 23(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37112169

RESUMO

The status of zinc oxide (ZnO) arresters is directly related to the safety of power grids. However, as the service life of ZnO arresters increases, their insulation performance may decrease due to factors such as operating voltage and humidity, which can be identified through the measurement of leakage current. Tunnel magnetoresistance (TMR) sensors with high sensitivity, good temperature stability, and small size are excellent for measuring leakage current. This paper constructs a simulation model of the arrester and investigates the deployment of the TMR current sensor and the size of the magnetic concentrating ring. The arrester's leakage current magnetic field distribution under different operating conditions is simulated. The simulation model can aid in optimizing the detection of leakage current in arresters using TMR current sensors, and the findings serve as a basis for monitoring the condition of arresters and improving the installation of current sensors. The TMR current sensor design offers potential advantages such as high accuracy, miniaturization, and ease of distributed application measurement, making it suitable for large-scale use. Finally, the validity of the simulations and conclusions is verified through experiments.

8.
Acta Biomater ; 138: 182-192, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34774784

RESUMO

Polyelectrolyte complex (PEC) hydrogels are advantageous as therapeutic agent and cell carriers. However, due to the weak nature of physical crosslinking, PEC swelling and cargo burst release are easily initiated. Also, most current cell-laden PEC hydrogels are limited to fibers and microcapsules with unfavorable dimensions and structures for practical implantations. To overcome these drawbacks, alginate (Alg)/poly-L-ornithine (PLO) PEC hydrogels are fabricated into microcapsules, fibers, and bulk scaffolds to explore their feasibility as drug and cell carriers. Stable Alg/PLO microcapsules with controllable shapes are obtained through aqueous electrospraying technique, which avoids osmotic shock and prolongs the release time. Model enzyme and nanosized cargos are successfully encapsulated and continuously released for more than 21 days. Alg/PLO PEC fibers are then prepared to encapsulate brown adipose progenitors (BAPs) and Jurkat T cells. The electrostatic interactions between Alg and PLO are found to facilitate the printability and self-support ability of Alg/PLO bioinks. Alg/PLO PEC fibers and scaffolds support cell proliferation, differentiation, and functionalization. These results demonstrate new options for biocompatible PEC hydrogel preparation and improve the understanding of PEC hydrogels as drug and cell carriers. STATEMENT OF SIGNIFICANCE: In this study, the concept of polyelectrolyte complex hydrogel networks as drug and cell carriers has been demonstrated. Their feasibility to achieve sustained drug release and cell functionality was explored, from microcapsules to fibers to three-dimension printed scaffolds. PEC microcapsules with controllable shapes were obtained. Therapeutic drugs can be encapsulated and continuously release for more than 21 days. Benefiting from the dynamic interactions of physically crosslinked PEC, self-healing fibers were achieved. Besides, the electrostatic interactions between polyelectrolytes were found to facilitate the printability and self-support ability of PEC bioinks. The PEC fibers and scaffolds with controllable structure supported cell proliferation, differentiation, and function. The outcome of current research promotes design of new biocompatible PEC hydrogels and potential drug and cell carriers.


Assuntos
Alginatos , Hidrogéis , Peptídeos , Polieletrólitos , Alicerces Teciduais
9.
Biofabrication ; 14(1)2021 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-34905737

RESUMO

In the past decade, cartilage tissue engineering has arisen as a promising therapeutic option for degenerative joint diseases, such as osteoarthritis, in the hope of restoring the structure and physiological functions. Hydrogels are promising biomaterials for developing engineered scaffolds for cartilage regeneration. However, hydrogel-delivered mesenchymal stem cells or chondrocytes could be exposed to elevated levels of reactive oxygen species (ROS) in the inflammatory microenvironment after being implanted into injured joints, which may affect their phenotype and normal functions and thereby hinder the regeneration efficacy. To attenuate ROS induced side effects, a multifunctional hydrogel with an innate anti-oxidative ability was produced in this study. The hydrogel was rapidly formed through a dynamic covalent bond between phenylboronic acid grafted hyaluronic acid (HA-PBA) and poly(vinyl alcohol) and was further stabilized through a secondary crosslinking between the acrylate moiety on HA-PBA and the free thiol group from thiolated gelatin. The hydrogel is cyto-compatible and injectable and can be used as a bioink for 3D bioprinting. The viscoelastic properties of the hydrogels could be modulated through the hydrogel precursor concentration. The presence of dynamic covalent linkages contributed to its shear-thinning property and thus good printability of the hydrogel, resulting in the fabrication of a porous grid construct and a meniscus like scaffold at high structural fidelity. The bioprinted hydrogel promoted cell adhesion and chondrogenic differentiation of encapsulated rabbit adipose derived mesenchymal stem cells. Meanwhile, the hydrogel supported robust deposition of extracellular matrix components, including glycosaminoglycans and type II collagen, by embedded mouse chondrocytesin vitro. Most importantly, the hydrogel could protect encapsulated chondrocytes from ROS induced downregulation of cartilage-specific anabolic genes (ACAN and COL2) and upregulation of a catabolic gene (MMP13) after incubation with H2O2. Furthermore, intra-articular injection of the hydrogel in mice revealed adequate stability and good biocompatibilityin vivo. These results demonstrate that this hydrogel can be used as a novel bioink for the generation of 3D bioprinted constructs with anti-ROS ability to potentially enhance cartilage tissue regeneration in a chronic inflammatory and elevated ROS microenvironment.


Assuntos
Bioimpressão , Engenharia Tecidual , Animais , Bioimpressão/métodos , Cartilagem , Condrócitos , Gelatina/farmacologia , Ácido Hialurônico/química , Hidrogéis/química , Hidrogéis/farmacologia , Peróxido de Hidrogênio , Camundongos , Coelhos , Espécies Reativas de Oxigênio/metabolismo , Engenharia Tecidual/métodos , Alicerces Teciduais/química
10.
FASEB J ; 35(12): e22066, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34822203

RESUMO

Rotator cuff tendon injuries often occur at the tendon-to-bone interface (i.e., enthesis) area, with a high prevalence for the elderly population, but the underlying reason for this phenomenon is still unknown. The objective of this study is to identify the histological, molecular, and biomechanical alterations of the rotator cuff enthesis with maturation and aging in a mouse model. Four different age groups of mice (newborn, young, adult, and old) were studied. Striking variations of the entheses were observed between the newborn and other matured groups, with collagen content, proteoglycan deposition, collagen fiber dispersion was significantly higher in the newborn group. The compositional and histological features of young, adult, and old groups did not show significant differences, except having increased proteoglycan deposition and thinner collagen fibers at the insertion sites in the old group. Nanoindentation testing showed that the old group had a smaller compressive modulus at the insertion site when compared with other groups. However, tensile mechanical testing reported that the old group demonstrated a significantly higher failure stress when compared with the young and adult groups. The proteomics analysis detected dramatic differences in protein content between newborn and young groups but minor changes among young, adult, and old groups. These results demonstrated: (1) the significant alterations of the enthesis composition and structure occur from the newborn to the young time period; (2) the increased risk of rotator cuff tendon injuries in the elderly population is not solely because of old age alone in the rodent model.


Assuntos
Envelhecimento , Osso e Ossos/patologia , Proteoglicanas/metabolismo , Proteoma/metabolismo , Lesões do Manguito Rotador/patologia , Manguito Rotador/patologia , Tendões/patologia , Fatores Etários , Animais , Fenômenos Biomecânicos , Osso e Ossos/metabolismo , Colágeno/metabolismo , Modelos Animais de Doenças , Camundongos , Manguito Rotador/metabolismo , Lesões do Manguito Rotador/etiologia , Lesões do Manguito Rotador/metabolismo , Tendões/metabolismo , Cicatrização
11.
J Mater Chem B ; 9(35): 7182-7195, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-33651063

RESUMO

Due to their intrinsic injectable and self-healing characteristics, dynamic hydrogels, based on dynamic covalent bonds, have gained a great attention. In this study, a novel dynamic hydrogel based on the boronic ester dynamic covalent bond is facilely developed using phenylboronic acid-modified hyaluronic acid (HA-PBA) and plant-derived polyphenol-tannic acid (TA). The dynamic hydrogel gelated quickly under mild conditions and had favorable viscoelastic properties with good self-healing and shear-thinning capabilities. Moreover, the simultaneous utilization of TA as a reductant for the green synthesis of silver nanoparticles (AgNP) inspired the preparation of a TA-reduced AgNP hybrid dynamic hydrogel with potent and broad-spectrum antibacterial activities. The dynamic hydrogels could also be applied for pH- and reactive oxygen species (ROS)-responsive release of loaded protein molecules without showing evident cytotoxicity and hemolysis in vitro. In addition, the dynamic hydrogels showed the anti-oxidative properties of high free radical and ROS scavenging capacity, which was verified by the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radical assay and ROS fluorescence staining. Overall, this novel class of cytocompatible, self-healing, dual stimuli responsive, antibacterial, anti-oxidative, and injectable hydrogels could be promising as a wound dressing for chronic wound healing.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Materiais Biocompatíveis/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Taninos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antioxidantes/síntese química , Antioxidantes/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Compostos de Bifenilo/antagonistas & inibidores , Ácidos Borônicos/química , Ácidos Borônicos/farmacologia , Células Cultivadas , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Hidrogéis/síntese química , Hidrogéis/química , Hidrogéis/farmacologia , Teste de Materiais , Camundongos , Testes de Sensibilidade Microbiana , Conformação Molecular , Tamanho da Partícula , Picratos/antagonistas & inibidores , Polifenóis/química , Polifenóis/farmacologia , Taninos/química
12.
Drug Dev Res ; 82(7): 999-1007, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33634899

RESUMO

Endothelial dysfunction is closely related to various cardiovascular diseases. Oxidative stress and apoptosis are involved in the progress of endothelial dysfunction. Irigenin (IR) has antioxidative properties. We investigated IR as a novel therapy for angiotensin II (Ang II)-induced endothelial dysfunction and explored the potential mechanisms of IR. After human umbilical vein endothelial cell lines (HUVECs) were treated with Ang II (100, 200, 300 and 400 nmol/L) alone, IR (2.5, 5, 10, 20 and 40 µmol/L) alone or Ang II plus IR for 24 h, HUVECs viability, lactate dehydrogenase (LDH), apoptosis, oxidative stress, apoptosis-related protein and nuclear factor E2-related factor 2 (Nrf2) levels were detected by Cell Counting Kit (CCK)-8 assay, enzyme-linked immunosorbent assay, flow cytometry and western blot. Transfection rate of Nrf2 was detected by western blot. In the next rescue experiment, we used silent Nrf2 (siNrf2) to verify the previous experimental results. Different concentrations' Ang II repressed HUVECs viability and increased LDH release, and different concentrations' IR did not affect HUVECs viability or LDH release. Furthermore, IR elevated cell viability and Nrf2 level, inhibited LDH release, apoptosis, oxidative stress and apoptosis-related protein levels in Ang II-induced HUVECs. More important, siNrf2 suppressed the expression of Nrf2, and siNrf2 abrogated the protective effect of IR on Ang II-induced Nrf2 expression, cell viability, LDH activity, oxidative stress generation and apoptosis-related protein in HUVECs. IR protected HUVECs from Ang II-induced oxidative stress and apoptosis injury by activating Nrf2 pathway.


Assuntos
Angiotensina II , Fator 2 Relacionado a NF-E2 , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Apoptose , Sobrevivência Celular , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Isoflavonas , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
13.
Food Chem ; 339: 127941, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152853

RESUMO

The effect and mechanism of myofibrillar protein (MP) gelation influenced by konjac glucomannan (KG) addition were studied. The KG addition significantly improved gel strength and water holding capability (WHC) of MP-KG composite gel, but it had additive limitation at 1.0%. The SEM showed that KG (<1.0%) reduced the appearance of moisture channels and promoted the formation of an integral MP gel network. Raman spectroscopy showed that KG addition (<1.0%) promoted the protein unfolding and the interaction of hydrophobic groups during thermal processing. However, the KG (>1.0%) would form continuous viscous hydrogel and interpenetrate with the MP solution, which hindered the interaction of hydrophobic groups during thermal process, and the MP formed a loose and degraded final structure. Hence, MP gels produced with the addition of KG underwent a transformation from a loose structure to a compact structure to an unaggregated structure, which was influenced by moisture stability and phase separation behavior.


Assuntos
Mananas/química , Proteínas Musculares/química , Géis , Interações Hidrofóbicas e Hidrofílicas , Estabilidade Proteica , Desdobramento de Proteína , Reologia , Água/química
14.
Meat Sci ; 170: 108228, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32807542

RESUMO

The effects of three polysaccharides on the textural properties and microstructure of myofibrillar protein (MP) gels were studied. The gel strength and rheological properties of composite MP gels were significantly improved with insoluble dietary fibre (DF) and modified starch (MS) addition, while konjac glucomannan (KG) had limited effects at 1% addition. The SEM images indicated that moisture extrusion formed moisture channels and deteriorated the aggregation of MP gel networks during the thermal process. The polysaccharides stabilized moisture and reduced the appearance of moisture channels in the gel network, thereby promoting the formation of compact and integral gel networks. The MP-polysaccharide mixture is a thermally incompatible system and presented two main forms after the thermal process: 1) the "trapped" structure and 2) the "interpenetrated" structure. In the "trapped" structure, the MP was the dominant structure of the composite gel network. In the "interpenetrated" structure, the continuous polysaccharide hydrogel substantially hindered the aggregation of MP gel networks. Principal component analysis showed that the phase behaviour and moisture stability of polysaccharides significantly influenced the textural quality and microstructure of composite MP gelation. The study indicated that polysaccharides that contribute to moisture stability and form a "trapped structure" (phase behaviour) are ideal fat replacements for improving composite gel properties, especially DF.


Assuntos
Produtos da Carne/análise , Miofibrilas/química , Polissacarídeos/química , Animais , Fibras na Dieta , Géis/química , Mananas , Proteínas Musculares/química , Miofibrilas/ultraestrutura , Amido , Suínos
15.
Bioact Mater ; 5(3): 636-643, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32405578

RESUMO

Repairing massive rotator cuff tendon defects remains a challenge due to the high retear rate after surgical intervention. 3D printing has emerged as a promising technique that enables the fabrication of engineered tissues with heterogeneous structures and mechanical properties, as well as controllable microenvironments for tendon regeneration. In this study, we developed a new strategy for rotator cuff tendon repair by combining a 3D printed scaffold of polylactic-co-glycolic acid (PLGA) with cell-laden collagen-fibrin hydrogels. We designed and fabricated two types of scaffolds: one featuring a separate layer-by-layer structure and another with a tri-layered structure as a whole. Uniaxial tensile tests showed that both types of scaffolds had improved mechanical properties compared to single-layered PLGA scaffolds. The printed scaffold with collagen-fibrin hydrogels effectively supported the growth, proliferation, and tenogenic differentiation of human adipose-derived mesenchymal stem cells. Subcutaneous implantation of the multilayered scaffolds demonstrated their excellent in vivo biocompatibility. This study demonstrates the feasibility of 3D printing multilayered scaffolds for application in rotator cuff tendon regeneration.

16.
Biofabrication ; 12(3): 035020, 2020 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-32369796

RESUMO

Functional reconstruction of craniomaxillofacial defects is challenging, especially for the patients who suffer from traumatic injury, cranioplasty, and oncologic surgery. Three-dimensional (3D) printing/bioprinting technologies provide a promising tool to fabricate bone tissue engineering constructs with complex architectures and bioactive components. In this study, we implemented multi-material 3D printing to fabricate 3D printed PCL/hydrogel composite scaffolds loaded with dual bioactive small molecules (i.e. resveratrol and strontium ranelate). The incorporated small molecules are expected to target several types of bone cells. We systematically studied the scaffold morphologies and small molecule release profiles. We then investigated the effects of the released small molecules from the drug loaded scaffolds on the behavior and differentiation of mesenchymal stem cells (MSCs), monocyte-derived osteoclasts, and endothelial cells. The 3D printed scaffolds, with and without small molecules, were further implanted into a rat model with a critical-sized mandibular bone defect. We found that the bone scaffolds containing the dual small molecules had combinational advantages in enhancing angiogenesis and inhibiting osteoclast activities, and they synergistically promoted MSC osteogenic differentiation. The dual drug loaded scaffolds also significantly promoted in vivo mandibular bone formation after 8 week implantation. This work presents a 3D printing strategy to fabricate engineered bone constructs, which can likely be used as off-the-shelf products to promote craniomaxillofacial regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Mandíbula/fisiologia , Impressão Tridimensional , Bibliotecas de Moléculas Pequenas/administração & dosagem , Bibliotecas de Moléculas Pequenas/farmacologia , Alicerces Teciduais/química , Animais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Mandíbula/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ratos Sprague-Dawley
17.
Carbohydr Polym ; 229: 115449, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826526

RESUMO

In this study, the effect and mechanism of myofibrillar protein (MP) gelation influenced by the hydration characteristic of three polysaccharides were studied through puncture test, paraffin section, SEM and Raman spectroscopy. The gel strength and water holding capability reflect that MP gelation only significantly improves until modified starch (MS) addition beyond 1.0%. The MS granule improves MP gel property through simply physical swelling effect. At gelatinization temperature, MS absorbs the moisture nearby to compress the MP three-dimensional networks, but the swelling effect is limited. The insoluble dietary fiber (IDF) improves MP gelation property through moisture stability. The IDF addition could lessen the appearance of moisture channel in MP gel networks and promote the interaction of hydrophobic groups. The MP gelation with 2.0% IDF addition has the highest gel strength (279 g) and water holding capability (91.87%). The konjac glucomannan (KG) (>1.0%) could degrade gel property of MP gelation through interpenetrate structure, because the KG hydrogel hinders the aggregation of the MP gel networks. In conclusion, the IDF, which has strong water-holding capability at room temperature and distribute individually, is the best polysaccharides-based fat replacement in low-fat restructured products.


Assuntos
Fibras na Dieta , Hidrogéis/química , Mananas/química , Proteínas Musculares/metabolismo , Miofibrilas/química , Amido/química , Animais , Substitutos da Gordura/química , Manihot/química , Proteínas Musculares/química , Conformação Proteica/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Saccharum/química , Suínos
18.
Bioact Mater ; 4: 256-260, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31667442

RESUMO

3D printing/bioprinting are promising techniques to fabricate scaffolds with well controlled and patient-specific structures and architectures for bone tissue engineering. In this study, we developed a composite bioink consisting of silk fibroin (SF), gelatin (GEL), hyaluronic acid (HA), and tricalcium phosphate (TCP) and 3D bioprinted the silk fibroin-based hybrid scaffolds. The 3D bioprinted scaffolds with dual crosslinking were further treated with human platelet-rich plasma (PRP) to generate PRP coated scaffolds. Live/Dead and MTT assays demonstrated that PRP treatment could obviously promote the cell growth and proliferation of human adipose derived mesenchymal stem cells (HADMSC). In addition, the treatment of PRP did not significantly affect alkaline phosphatase (ALP) activity and expression, but significantly upregulated the gene expression levels of late osteogenic markers. This study demonstrated that the 3D printing of silk fibroin-based hybrid scaffolds, in combination with PRP post-treatment, might be a more efficient strategy to promote osteogenic differentiation of adult stem cells and has significant potential to be used for bone tissue engineering.

19.
Food Chem ; 275: 770-777, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724262

RESUMO

The effects of insoluble dietary fiber (IDF) on heat-induced gelation properties, such as microstructural changes and the molecular conformation of myofibrillar proteins (MP), were analyzed by image analyses and Raman spectroscopy. Scanning electron microscopy revealed that pure MP gelation contained a loose and dispersed network with interconnected water channels. With IDF addition, the lacunarity and the particle size of water pores both significantly decreased (P < 0.05) and fractal dimension significantly increased (P < 0.05), which indicated the formation of a homogenous and compact three-dimensional network. Through Raman spectra, IDF addition resulted in modification of amide I and III regions, by a significant decrease in α-helix content, accompanied by an increase of ß-sheets, ß-turns, and random coil content (P < 0.05); the intensity of CU+005CH stretching vibrations bending vibrations bands were significantly decreased (P < 0.05). Principal component analyses showed significant correlations between textual property, microstructure and molecular conformations. Cluster analyses indicated IDF improved the functionality of MP gel by 1): IDF stable the moisture phase 2) "concentrated" MP promoted structural integrity and compact gelation.


Assuntos
Fibras na Dieta/análise , Géis/química , Proteínas Musculares/química , Animais , Análise por Conglomerados , Produtos da Carne/análise , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Análise de Componente Principal , Estrutura Secundária de Proteína , Análise Espectral Raman , Suínos
20.
ACS Biomater Sci Eng ; 5(10): 5284-5294, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33455233

RESUMO

Nerve guidance conduit (NGC)-infilling substrates have been reported to facilitate the regeneration of injured peripheral nerves (PNs), especially for large nerve gaps. In this study, longitudinally oriented electrospun core-sheath nanoyarns (csNYs), consisting of a polylactic acid microfiber core and an electrospun nanofiber sheath, were fabricated for potential PN tissue engineering applications. Our novel csNY displayed a well-aligned nanofibrous surface topography, resembling the ultrastructure of axons and fascicles of a native PN system, and it also provided a mechanically stable structure. The biological results showed that the csNY significantly enhanced the attachment, growth, and proliferation of human adipose derived mesenchymal stem cells (hADMSC) and also promoted the migration, proliferation, and phenotype maintenance of rabbit Schwann cells (rSCs). Our csNY notably increased the differentiation capability of hADMSC into SC-like cells (hADMSC-SC), in comparison with a 2D tissue culture polystyrene plate. More importantly, when combined with the appropriate induction medium, our csNY promoted hADMSC-SC to express high levels of myelination-associated markers. Overall, this study demonstrates that our csNYs have great potential to serve as not only ideal in vitro culture models for understanding SC-axon interaction and SC myelination but also as promising NGC-infilling substrates for PN regeneration applications.

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