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oe1(光电查) - 科学论文

19 条数据
?? 中文(中国)
  • A laser-cutting-based manufacturing process for the generation of three-dimensional scaffolds for tissue engineering using Polycaprolactone/Hydroxyapatite composite polymer

    摘要: A manufacturing process for sheet-based stacked scaffolds (SSCs) based on laser-cutting (LC) was developed. The sheets consist of Polycaprolactone/Hydroxyapatite (PCL/HA) composite material. Single sheets were cut from a PCL/HA foil and stacked to scaffolds with interconnecting pores of defined sizes. HA quantities up to 50% were processable with high reproducibility, while the accuracy was dependent on the applied laser power. The smallest achievable pore sizes were about 40 μm, while the smallest stable solid structures were about 125 μm. The human mesenchymal stem cell line SCP-1 was cultured on the manufactured PCL/HA scaffolds. The cells developed a natural morphology and were able to differentiate to functional osteoblasts. The generation of PCL/HA SSCs via LC offers new possibilities for tissue engineering (TE) approaches. It is reliable and fast, with high resolution. The SSC approach allows for facile cell seeding and analysis of cell fate within the three-dimensional cell culture, thus allowing for the generation of functional tissue constructs.

    关键词: laser-cutting,Tissue engineering,scaffold

    更新于2025-11-21 11:24:58

  • Visualizing Cell-Laden Fibrin-Based Hydrogels using Cryogenic Scanning Electron Microscopy and Confocal Microscopy

    摘要: The present investigation explores the microscopic aspects of cell-laden hydrogels at high resolutions, using three-dimensional cell cultures in semi-synthetic constructs that are of very-high water content (>98% water). The study aims to provide an imaging strategy for these constructs, while minimizing artifacts. Constructs of PEG-fibrinogen (PEG-Fb) and fibrin hydrogels containing embedded mesenchymal cells (human dermal fibroblasts) were first imaged by confocal microscopy. Next, high resolution scanning electron microscopy (HR-SEM) was used to provide images of the cells within the hydrogels, at submicron resolutions. Because it was not possible to obtain artifact-free images of the hydrogels using room-temperature HR-SEM, a cryogenic HR-SEM (cryo-HR-SEM) imaging methodology was employed to visualize the sample while preserving the natural hydrated state of the hydrogel. The ultrastructural details of the constructs were observed at subcellular resolutions, revealing numerous cellular components, the biomaterial in its native configuration, and the uninterrupted cell membrane as it relates with the biomaterial in the hydrated state of the construct. Constructs containing microscopic albumin microbubbles were also imaged using these methodologies to reveal fine details of the interaction between the cells, the microbubbles and the hydrogel. Taken together with the confocal microscopy, this imaging strategy provides a more complete picture of the hydrated state of the hydrogel network with cells inside. As such, this methodology addresses some of the challenges of obtaining this information in amorphous hydrogel systems containing a very-high water content (>98%) with embedded cells. Such insight may lead to better hydrogel-based strategies for tissue engineering and regeneration.

    关键词: Fibrin,Electron Microscopy,Hydrogel,Tissue Engineering,Scaffold,Confocal Microscopy

    更新于2025-11-21 11:08:12

  • Luminescent Lanthanide–Collagen Peptide Framework for pH-Controlled Drug Delivery

    摘要: Collagen mimetic scaffolds play a pivotal role in regenerative medicine and tissue engineering due to their extraordinary structural and biological features. We have herein for the first time reported the construction of luminescent lanthanide-collagen peptide hybrid three-dimensional nanofibrous scaffolds, which well mimic the characteristic architectural structure of native collagen. Three collagen mimetic peptides composed of repetitive central (GPO)7 sequences and altered terminal amino acids, have been shown to consistently self-assemble to form biocompatible nanofibers under the trigger of a variety of lanthanide ions, which also functionalize the assembled materials with easily tunable photoluminescence. Furthermore, the collagen peptide-lanthanide hybrid scaffolds possess programmable pH-responsive features. The lanthanide ion-mediated assembly of all the three collagen peptides are conveniently and reversibly regulated by pH, while their pH-dependent patterns are finely tuned by the identity of terminal amino acids. Using camptothecin and cefoperazone sodium as two model drugs, the drug-loading and releasing efficiency of the collagen peptide-lanthanide scaffolds are nicely modulated by pH, demonstrating the efficacy of these nanofibrous scaffolds as pH-responsive drug carriers. These novel luminescent collagen peptide-lanthanide scaffolds provide a facile system for pH-controlled drug delivery, suggesting promising applications in the development of therapies for many diseases.

    关键词: self-assembly,scaffold,pH-responsive,Collagen mimetic peptides,drug delivery

    更新于2025-09-23 15:23:52

  • Q-graphene-scaffolded covalent organic frameworks as fluorescent probes and sorbents for the fluorimetry and removal of copper ions

    摘要: Metal-free fluorescent covalent organic frameworks (COFs) were synthesized initially with Q-Graphene (QG) scaffolds by the one-step covalent reactions of melamine-aldehyde and phenol-aldehyde poly-condensations using paraformaldehyde. It was discovered that onion-like hollow QG, which consists of multi-layer graphene and different carbon allotropes having a high proportion of folded edges and surface defects, could endow the scaffolded COFs with enhanced green fluorescence and environmental stability. Unexpectedly, they could exhibit the powerful absorption for Cu2+ ions resulting in the specific quenching of fluorescence. A fluorimetric strategy with QG-scaffolded COFs was thereby developed to probe Cu2+ ions separately in blood and wastewater with the linear concentration ranges of 0.0010 - 10.0 μM (limit of detection of 0.50 nM) and 0.0032 - 32.0 μM (limit of detection of 2.4 nM), respectively, promising the potential applications for the field-applicable monitoring of Cu2+ ions in the clinical and environmental analysis fields. In addition, the prepared COFs sorbents were employed to absorb Cu2+ ions in wastewater showing high removal efficiency. More importantly, such an one-pot fabrication route with hollow QG scaffolds may be tailorable extensively for the preparation of a variety of metal-free multifunctional COFs with enhanced fluorescence, water solubility, environmental stability, and metal removal capability.

    关键词: Q-Graphene Scaffold;Covalent Organic Frameworks;Fluorescent Analysis;Removal Sorbents;Copper Ions

    更新于2025-09-23 15:23:52

  • A versatile scaffold for facile synthesis of fluorescent cyano-substituted stilbenes

    摘要: Here we report the facile derivatization of a cyano-substituted stilbene into higher π-extended analogues. The cyano-substituted stilbene, which serves as a synthetic scaffold, has a bromo group and a formyl group on its 4- and 4’-position of the phenylene rings and thus readily undergoes selective transformation into other functional groups using various simple organic reactions. The resultant π-conjugated molecules that contain a cyano-substituted stilbene skeleton exhibit fluorescence in solution and in the solid state.

    关键词: Scaffold,Fluorescence,π-Conjugated Molecule

    更新于2025-09-23 15:23:52

  • Impact of procedural characteristics on coronary vessel wall healing following implantation of second-generation drug-eluting absorbable metal scaffold in patients with de novo coronary artery lesions: an optical coherence tomography analysis

    摘要: Aims Second-generation drug-eluting absorbable metal scaffold (DREAMS 2G) is an alternative novel device for treating coronary lesions. However, the relationship between in-scaffold dimensions after implantation of DREAMS 2G and vessel healing and luminal results at follow-up is unknown. The aim of this study is, therefore, to investigate whether the expansion index after implantation of DREAMS 2G as assessed by optical coherence tomography (OCT) impacts late luminal status and healing of the vessel wall. Methods and results This study comprises of a total 65 out of 123 patients who were enrolled in the BIOSOLVE-II trial. We assessed both qualitative and quantitative OCT findings and the expansion index of DREAMS 2G after implantation frame by frame using OCT. Expansion index was defined as minimum scaffold area/mean reference lumen area. The over-expansion group was also defined with expansion index >1.0. The total number of analysed frames at post-procedure and 6-month follow-up was 8243 and 8263 frames, respectively. At 6-month follow-up, in-scaffold healing was documented by the reduction of 82% in dissections, 93% in attached intra-luminal mass (ILM), 65% in non-attached ILM, and 76% in jailed side branch. The over-expansion group had significantly greater in-scaffold luminal volume loss (LVL) compared with the non-over-expansion group [over-expansion: 35.0 (18.5–52.1) mm3 vs. non-over-expansion: 21.0 (11.6–37.9) mm3, P = 0.039]. Conclusion Excellent in vivo healing process after implantation of DREAMS 2G was observed at 6 months. We found that higher expansion indices were associated with higher in-scaffold LVL at 6 months assessed by OCT.

    关键词: optical coherence tomography,drug-eluting absorbable metal scaffold,luminal volume loss

    更新于2025-09-23 15:22:29

  • From Aggregates to Porous Three-Dimensional Scaffolds through a Mechanochemical Approach to Design Photosensitive Chitosan Derivatives

    摘要: The crustacean processing industry produces large quantities of waste by-products (up to 70%). Such wastes could be used as raw materials for producing chitosan, a polysaccharide with a unique set of biochemical properties. However, the preparation methods and the long-term stability of chitosan-based products limit their application in biomedicine. In this study, different scale structures, such as aggregates, photo-crosslinked films, and 3D scaffolds based on mechanochemically-modified chitosan derivatives, were successfully formed. Dynamic light scattering revealed that aggregation of chitosan derivatives becomes more pronounced with an increase in the number of hydrophobic substituents. Although the results of the mechanical testing revealed that the plasticity of photo-crosslinked films was 5–8% higher than that for the initial chitosan films, their tensile strength remained unchanged. Different types of polymer scaffolds, such as flexible and porous ones, were developed by laser stereolithography. In vivo studies of the formed structures showed no dystrophic and necrobiotic changes, which proves their biocompatibility. Moreover, the wavelet analysis was used to show that the areas of chitosan film degradation were periodic. Comparing the results of the wavelet analysis and X-ray diffraction data, we have concluded that degradation occurs within less ordered amorphous regions in the polymer bulk.

    关键词: laser stereolithography,mechanochemical synthesis,long-term stability,tissue reaction,chitosan,scaffold

    更新于2025-09-23 15:22:29

  • Polybenzyl Glutamate Biocompatible Scaffold Promotes the Efficiency of Retinal Differentiation toward Retinal Ganglion Cell Lineage from Human-Induced Pluripotent Stem Cells

    摘要: Optic neuropathy is one of the leading causes of irreversible blindness caused by retinal ganglion cell (RGC) degeneration. The development of induced pluripotent stem cell (iPSC)-based therapy opens a therapeutic window for RGC degeneration, and tissue engineering may further promote the efficiency of differentiation process of iPSCs. The present study was designed to evaluate the effects of a novel biomimetic polybenzyl glutamate (PBG) scaffold on culturing iPSC-derived RGC progenitors. The iPSC-derived neural spheres cultured on PBG scaffold increased the differentiated retinal neurons and promoted the neurite outgrowth in the RGC progenitor layer. Additionally, iPSCs cultured on PBG scaffold formed the organoid-like structures compared to that of iPSCs cultured on cover glass within the same culture period. With RNA-seq, we found that cells of the PBG group were differentiated toward retinal lineage and may be related to the glutamate signaling pathway. Further ontological analysis and the gene network analysis showed that the differentially expressed genes between cells of the PBG group and the control group were mainly associated with neuronal differentiation, neuronal maturation, and more specifically, retinal differentiation and maturation. The novel electrospinning PBG scaffold is beneficial for culturing iPSC-derived RGC progenitors as well as retinal organoids. Cells cultured on PBG scaffold differentiate effectively and shorten the process of RGC differentiation compared to that of cells cultured on coverslip. The new culture system may be helpful in future disease modeling, pharmacological screening, autologous transplantation, as well as narrowing the gap to clinical application.

    关键词: induced pluripotent stem cells,retinal ganglion cells,tissue engineering,glaucoma,optic neuropathy,polybenzyl glutamate,electrospinning scaffold

    更新于2025-09-23 15:22:29

  • Evolution of pure hydrocarbon hosts: simpler structure, higher performance and universal application in RGB phosphorescent organic light-emitting diodes

    摘要: In the field of phosphorescent organic light-emitting diodes (PhOLEDs), designing high-efficiency universal host materials for red, green and blue (RGB) phosphors has been quite a challenge. To date, most of the high-efficiency universal hosts reported incorporate heteroatoms, which have a crucial role in the device performance. However, the introduction of different kinds of heterocycles increases the design complexity and cost of the target material and also creates potential instability in the device performance. In this work, we show that pure aromatic hydrocarbon hosts designed with the 9,90-spirobifluorene scaffold are high-efficiency and versatile hosts for PhOLEDs. With external quantum efficiencies of 27.3%, 26.0% and 27.1% for RGB PhOLEDs respectively, this work not only reports the first examples of high-efficiency pure hydrocarbon materials used as hosts in RGB PhOLEDs but also the highest performance reported to date for a universal host (including heteroatom-based hosts). This work shows that the PHC design strategy is promising for the future development of the OLED industry as a high-performance and low-cost option.

    关键词: RGB phosphors,PhOLEDs,external quantum efficiencies,phosphorescent organic light-emitting diodes,universal host materials,pure aromatic hydrocarbon hosts,9,90-spirobifluorene scaffold

    更新于2025-09-23 15:21:01

  • Drug-releasing Biopolymeric Structures Manufactured via Stereolithography

    摘要: Additive manufacturing (AM) techniques, such as stereolithography (SLA), enable the preparation of designed complex structures. AM has gained interest especially in the tissue engineering field due to the possibility to manufacture patient specific implants. However, AM could be useful also in controlled drug release applications, since the size and shape of the device, pore architecture and surface to volume ratio can be accurately designed. In this study, SLA was used to prepare polycaprolactone scaffold structures containing the model drug lidocaine. The release of lidocaine was studied and the influence of porosity and surface to volume ratio of structures to the drug release was analyzed. Porous samples released lidocaine faster compared to solid ones, whereas the degree of porosity and surface to volume ratio did not have a clear effect on the drug release profile.

    关键词: drug delivery,stereolithography,additive manufacturing,drug release,lidocaine,scaffold,controlled release,polycaprolactone

    更新于2025-09-23 15:21:01