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oe1(光电查) - 科学论文

14 条数据
?? 中文(中国)
  • Fabrication of conductive fibrous scaffold for photoreceptor differentiation of mesenchymal stem cell

    摘要: Conductive nanofibrous scaffolds with that can conduct electrical current have a great potential in neural tissue engineering. The purpose of this study was to survey effects of electrical stimulation and polycaprolactone/polypyrrole/multiwall carbon nanotube (PCL/PPY/MWCNTs) fibrous scaffold on photoreceptor differentiation of trabecular meshwork mesenchymal stem cells (TM‐MSCs). PCL/PPY/MWCNTs scaffold was made by electrospinning method. TM‐MSCs were seeded on PCL/PPY/MWCNTs scaffold and stimulated with a potential of 115 V/m. Scanning electron microscopy, transmission electron microscopy, and FT‐IR were used to evaluate the fabricated scaffold. Immunofluorescence and quantitative real‐time polymerase chain reaction were used to examine differentiated cells. Scanning electron microscopy, transmitting electron microscopy, and FT‐IR confirmed the creation of the composite structure of fibers. RT‐qPCR analysis showed that the expression of rhodopsin and peripherin genes in electrically stimulated cells were significantly higher (5.7‐ and 6.23‐fold, respectively; p ≤ 0.05) than those with no electrical stimulation. Collectively, it seems that the combination of PCL/PPY/MWCNTs scaffold, as a suitable conductive scaffold, and electrical stimulation could be an effective approach in the differentiation of stem cells in retinal tissue engineering.

    关键词: electrical conductive,trabecular meshwork mesenchymal stem cells,photoreceptor‐like cells,nanostructure

    更新于2025-11-14 15:18:02

  • Novel fluorescent triazinobenzimidazole derivatives as probes for labelling human A1 and A2B adenosine receptor subtypes

    摘要: The expression levels and the subcellular localization of adenosine receptors (ARs) are affected in several pathological conditions as a consequence of changes in adenosine release and metabolism. In this respect, labelled probes able to monitor the AR expression could be a useful tool to investigate different pathological conditions. Herein, novel ligands for ARs, bearing the fluorescent 7-nitrobenzofurazan (NBD) group linked to the N1 (1,2) or N10 (3,4) nitrogen of a triazinobenzimidazole scaffold, were synthesized. The compounds were biologically evaluated as fluorescent probes for labelling A1 and A2B AR subtypes in bone marrow-derived mesenchymal stem cells (BM-MSCs) that express both receptor subtypes. The binding affinity of the synthetized compounds towards the different AR subtypes was determined. The probe 3 revealed a higher affinity to A1 and A2B ARs, showing interesting spectroscopic properties, and it was selected as the most suitable candidate to label both AR subtypes in undifferentiated MSCs. Florescence confocal microscopy showed that compound 3 significantly labelled ARs on cell membranes and the fluorescence signal was decreased by the cell pre-incubation with the A1 AR and A2B AR selective agonists, R-PIA and BAY 60-6583, respectively, thus confirming the specificity of the obtained signal. In conclusion, compound 3 could represent a useful tool to investigate the expression pattern of both A1 and A2B ARs in different pathological and physiological processes. Furthermore, these results provide an important basis for the design of new and more selective derivatives able to monitor the expression and localization of each different ARs in several tissues and living cells.

    关键词: triazinobenzimidazole derivatives,Adenosine receptors,fluorescent probes,mesenchymal stem cells,A2B AR subtype

    更新于2025-09-23 15:21:01

  • [Advances in Experimental Medicine and Biology] || Photoresponsive Hydrogels with Photoswitchable Stiffness: Emerging Platforms to Study Temporal Aspects of Mesenchymal Stem Cell Responses to Extracellular Stiffness Regulation

    摘要: An extensive number of cell-matrix interaction studies have identi?ed matrix stiffness as a potent regulator of cellular properties and behaviours. Perhaps most notably, matrix stiffness has been demonstrated to regulate mesenchymal stem cell (MSC) phenotype and lineage commitment. Given the therapeutic potential for MSCs in regenerative medicine, signi?cant efforts have been made to understand the molecular mechanisms involved in stiffness regulation. These efforts have predominantly focused on using stiffness-de?ned polyacrylamide (PA) hydrogels to culture cells in 2D and have enabled elucidation of a number of mechano-sensitive signalling pathways. However, despite proving to be a valuable tool, these stiffness-de?ned hydrogels do not re?ect the dynamic nature of living tissues, which are subject to continuous remodelling during processes such as development, ageing, disease and regeneration. Therefore, in order to study temporal aspects of stiffness regulation, researchers have developed and exploited novel hydrogel substrates with in situ tuneable stiffness. In particular, photoresponsive hydrogels with photoswitchable stiffness are emerging as exciting platforms to study MSC responses to extracellular stiffness regulation. This chapter provides an introduction to the use of PA hydrogel substrates, the molecular mechanisms of mechanotransduction currently under investigation and the development of these emerging photoresponsive hydrogel platforms.

    关键词: Photoswitchable stiffness,Biophysical regulation,Photoresponsive,Cell-matrix interaction,Regenerative medicine,Polyacrylamide,Mechanotransduction,Stiffness regulation,Mesenchymal stem cells,Cell adhesion,Temporal,Hydrogel substrates

    更新于2025-09-23 15:21:01

  • Irradiation with blue light-emitting diode enhances osteogenic differentiation of stem cells from the apical papilla

    摘要: This study aimed to evaluate the effects of low-energy blue LED irradiation on the osteogenic differentiation of stem cells from the apical papilla (SCAPs). SCAPs were derived from human tooth root tips and were irradiated with 0 (control group), 1 J/cm2, 2 J/cm2, 3 J/cm2, or 4 J/cm2 blue light in osteogenic induction medium. Cell proliferation was analyzed using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay. Osteogenic differentiation activity was evaluated by monitoring alkaline phosphatase (ALP), alizarin red staining, and real-time polymerase chain reaction (RT-PCR). The results of the MTT assay indicated that SCAPs in the LED groups exhibited a lower proliferation rate than those in the control group, and there were statistically differences between the 2 J/cm2, 3 J/cm2, and 4 J/cm2 groups and the control group (P < 0.05). The results of the ALP and alizarin red analyses showed that blue LED promoted osteogenic differentiation of the SCAPs. And 4 J/cm2 blue light upregulates the expression levels of the osteogenic/dentinogenic genes ALP, dentin sialophosphoprotein (DSPP), dentin matrix protein-1 (DMP-1), and osteocalcin (OCN) in SCAPs. Our results confirmed that low-energy blue LED at 1 J/cm2, 2 J/cm2, 3 J/cm2, and 4 J/cm2 could inhibit the proliferation of SCAPs and promotes osteogenic differentiation of SCAPs. Further in vitro studies are required to explore the mechanisms of the effects by low-energy blue LED.

    关键词: Stem cells from apical papilla,Mesenchymal stem cells,Proliferation,Osteogenic differentiation,LED

    更新于2025-09-23 15:19:57

  • Fluorescent DTPA-Silk Fibroin Nanoparticles Radiolabeled with <sup>111</sup> In: A Dual Tool for Biodistribution and Stability Studies

    摘要: This work aims to provide an effective and novel dual tool for the biodistribution studies of biopolimeric nanoparticles by using modified silk fibroin nanoparticles as a model. This is an indispensable step in the evaluation of the applicability of biopolymeric nanoparticles as drug delivery systems. In this paper, we report a new facile method for radiolabeling silk fibroin nanoparticles conjugated to the chelating agent diethylenetriamine pentaacetic acid (DTPA) and tagged with fluorescein isothiocyanate (FITC). Nanoparticles were characterized by means of dynamic light scattering (DLS), scanning electron microscopy (SEM), infrared and fluorescence spectroscopy. The in vitro studies included the stability in biological media and the evaluation of the cytotoxicity of the nanoparticles in a cell culture. The in vivo study was focused in the scintigraphic study over 24 h conducted on New Zealand rabbits, after intra-articular injection of [111In]In-nanoparticles containing 8.03 ± 0.42 MBq. Biodistribution of the nanoparticles was assessed also ex vivo by fluorescence microscopy of post mortem biopsied organs. This radiolabeling method was reproducible and robust with high radiolabeling efficiency (~80 %) and high specific activity suitable for the in vivo studies. Radiolabeled nanoparticles, having hydrodynamic radius of 113.2 ± 2.3 nm, a polydispersity index (PdI) of 0.101 ± 0.015 and Z-potential of -30.1 ± 2.0 mV, showed and optimum retention in the articular space, without activity clearance up to 24 h post injection. Thus, an easy and robust radiolabeling method has been developed, and its applicability is demonstrated in vitro and in vivo studies, showing its value for future investigation of silk fibroin nanoparticles as versatile and stable (steady) local drug delivery systems for consideration as a therapeutic option, particularly in the treatment of joint disorders.

    关键词: biodistribution,theragnostic,radiolabeling,mesenchymal stem cells culture,FITC,silk fibroin nanoparticles,Indium-111,stability

    更新于2025-09-23 15:19:57

  • The Effect of Laser Structuring of Carbon Nanotubes on the Proliferation of Chondroblasts and Mesenchymal Stem Cells

    摘要: The density of cartilage cells (chondroblasts) proliferating on a silicon substrate coated with vertically oriented arrays of multi-walled carbon nanotubes (MWCNTs) was shown to be higher than on a pure silicon substrate. Electron microscopy showed that the cells in a nutrient medium affected the vertical position of the nanotubes in the array. A method for structuring the MWCNT arrays by 100-ns laser pulse scanning and abrasive water processing on planar substrates was developed. As a result of the structuring of the MWCNTs, the arrays become resistant to bending under the influence of the nutrient medium with mesenchymal stem cells. Structured MWCNT arrays were shown to have no toxic or pathological effect on the viability and morphology of stem cells. Thus, such materials can be suggested for use in cell-adhesive components of biomedical devices.

    关键词: carbon nanotubes,laser structuring,mesenchymal stem cells,chondroblasts,cell proliferation

    更新于2025-09-19 17:13:59

  • Modulation of the Mechanosensing of Mesenchymal Stem Cells by Laser-Induced Patterning for the Acceleration of Tissue Reconstruction through the Wnt/β-catenin Signaling Pathway Activation

    摘要: Growing evidence suggests that the physical microenvironment can guide cell fate. However, cells sense cues from the adjacent physical microenvironment over a limited distance. In the present study, murine mesenchymal stem cells (MSCs) and murine preosteoblastic cells (MC3T3-E1) behaviors are regulated by the cell–material interface using ordered-micro and disordered-nano patterned structures on Ti implants. The optimal bone formation structure is a stable wave (horizontal direction: ridge, 2.7 μm; grooves, 5.3 μm; and vertical direction: distance, 700 μm) with the appropriate density of nano-branches (6.0 per μm2). The repeated waves provide cells with directional guidance, and the disordered branches influence cell geometry by providing different spacing and density nanostructure. And micro-nano patterned structure can provide biophysical cues to direct cell phenotype development, including cell size, shape, and orientation, to influence cellular processes including survival, growth, and differentiation. Thus, the overlaid isotropic and anisotropic cues, ordered-micro and disordered-nano patterned structures, could transfer further and alter cell shape and induce nuclear orientation by activating Wnt/β-catenin signaling to promote integrinα5, integrinβ1, cadherin 2, Runx2, Opn, and Ocn. That canonical Wnt signaling inhibitor dickkopf1 further demonstrates osteogenic differentiation induced by ordered-micro and disordered-nano patterned structures, which is related to Wnt/β-catenin signaling. Our findings show the role of ordered microstructures and disordered nanostructures in modulating stem cell differentiation with potential medical applications.

    关键词: Mechanosensing,Implants,Surface modification,Mesenchymal stem cells,Laser,Signaling pathway

    更新于2025-09-12 10:27:22

  • Bone marrow mesenchymal stem cells encapsulated thermal-responsive hydrogel network bridges combined photo-plasmonic nanoparticulate system for the treatment of urinary bladder dysfunction after spinal cord injury

    摘要: Spinal cord injury (SCI) is a distressing injury and an irretrievable dramatic event that can debilitate victims for lifespan. Recovery and treatment of SCI is critical challenges for medicine, to overcome the hurdles stem cells and hydrogel scaffolds implantation is a boon for SCI recovery. In this regard, we reported the synthesis of Gold nanoparticles (Au NPs) loaded Agarose/ Poly (N-isopropylacrylamide) (PNIPAM) as promising materials for SCI treatment. Herein, Au NPs was synthesised by well-established citrate reduction method and the prepared materials were characterised by UV-visible spectroscopy (UV-vis), Transmission electron microscopy (TEM), Fourier- transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), and EDAX analysis. The microscopic images showed an elliptical or ovoid porous structure nature of hydrogel, and successful and homogenous loading of photo plasmonic nanoparticles into the hydrogel structure. The in vitro cell viability and inflammation analyses data exhibited that prepared hydrogels have no toxic to the cells and displayed high anti-regenerative ability with bone marrow Mesenchymal stem cells (MSCs) and macrophages cells. The in vivo analysis study demonstrated that the treated materials with encapsulated MSCs have greater nerve tissue regeneration efficacy which was confirmed by the results of BBB scores. The hind limb locomotion of treated model animals was totally vanished after post-operational surgery. It's established that implanted nano-hydrogel materials combined with MSCs have quicker recovery of motor function after post-operative surgery, when compared to the other implanted animal groups.

    关键词: Photo plasmonic,Spinal cord injury,Nanoparticles,Hydrogel,Mesenchymal stem cells

    更新于2025-09-12 10:27:22

  • Advances in Contact Angle, Wettability and Adhesion || Laser Surface Engineering of Polymeric Materials for Enhanced Mesenchymal Stem Cell Adhesion and Growth

    摘要: Owing to them being relatively inexpensive and easy to manipulate, polymers are becoming more widely used within the biomedical industry for several different applications. As an example, because of its high wear resistance, low moisture absorption and high chemical resistance, poly(ether ether ketone) is commonly used as a biomaterial in the healthcare and biomedical industries. However, poly(ether ether ketone) surface properties are not optimum for efficient or enhanced bio-functionality, leading it to have somewhat inferior wettability and adhesion characteristics. On account of this, many researchers are now looking to employ surface engineering techniques to improve and enhance the surface properties of poly(ether ether ketone), enhancing its biomimetic nature and improving the bio-adhesion properties. This chapter discusses the importance of Mesenchymal Stem Cells (MSCs), the biological applications of poly(ether ether ketone) and the application of lasers for surface engineering of poly(ether ether ketone) for modifying mesenchymal stem cell response. Through the application of CO2 laser surface engineering it has been shown that laser surface engineering can have a positive effect on the rate of human mesenchymal cell growth, highlighting the opportunities for the healthcare and biomedical industries to adopt such technique. In addition, discussion of including poly(ether ether ketone) and other polymer materials as bio-composite materials for future research is introduced for enhancing material properties.

    关键词: surface modification,surface engineering,poly(ether ether ketone),Mesenchymal stem cells,polymeric biomaterials,bio-engineering,laser treatment

    更新于2025-09-11 14:15:04

  • Combination of laser and human adipose-derived stem cells in repair of rabbit anal sphincter injury: a new therapeutic approach

    摘要: Background: Anal sphincter injury leads to fecal incontinence. Based on the regenerative capability of laser and human adipose-derived stem cells (hADSCs), this study was designed to assess the effects of co-application of these therapies on anal sphincter recovery after injury. Design: Male rabbits were assigned to equal groups (n = 7) including control, sphincterotomy, sphincterotomy treated with laser (660 nm, 90 s, immediately after sphincterotomy, daily, 14 days), hADSCs (2 × 106 hADSCs injected into injured area of the sphincter immediately after sphincterotomy), and laser + hADSCs. Ninety days after sphincterotomy, manometry and electromyography were performed, sphincter collagen content was evaluated, and Ki67, myosin heavy chain (MHC), skeletal muscle alpha-actin (ACTA1), vascular endothelial growth factor A (VEGFA), and vimentin mRNA gene expression were assessed. Results: The laser + hADSCs group had a higher resting pressure compared with the sphincterotomy (p < 0.0001), laser (p < 0.0001), and hADSCs (p = 0.04) groups. Maximum squeeze pressure was improved in all treated animals compared with the sphincterotomized animals (p < 0.0001), without a significant difference between treatments (p > 0.05). In the laser + hADSCs group, motor unit numbers were higher than those in the laser group (p < 0.0001) but did not differ from the hADSCs group (p = 0.075). Sphincterotomy increased collagen content, but the muscle content (p = 0.36) and collagen content (p = 0.37) were not significantly different between the laser + hADSCs and control groups. Laser + hADSCs increased ACTA1 (p = 0.001) and MHC (p < 0.0001) gene expression compared with laser or hADSCs alone and was associated with increased VEGFA (p = 0.009) and Ki67 mRNA expression (p = 0.01) and decreased vimentin mRNA expression (p < 0.0001) compared with laser. Conclusion: The combination of laser and hADSCs appears more effective than either treatment alone for promoting myogenesis, angiogenesis, and functional recovery after anal sphincterotomy.

    关键词: Lasers,Fecal incontinence,Mesenchymal stem cells

    更新于2025-09-11 14:15:04