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1.
Lasers Med Sci ; 39(1): 199, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39078465

RESUMEN

Non-small cell lung cancer (NSCLC) is a prevalent malignant tumor, and the commonly treatment modalities include surgery, radiotherapy, chemotherapy, etc. Currently, CT-guided percutaneous radiofrequency ablation (RFA) for the treatment of cancers has been widely performed. This study aimed to evaluate the safety and efficacy of this therapy in NSCLC patients. Thirty-five NSCLC patients were enrolled in this study and all received CT-guided percutaneous RFA therapy. The outcome measures included the changes in forced respiratory volume in the first second (FEV1), total lung volume (TLC), lesion size and computed tomography (CT) values of the region of interest (ROI) before and after treatment. The main efficacy measures comprised complete tumor ablation and local recurrence after initial treatment, as well as the objective response rate (ORR) and disease control rate (DCR) after 6 months of treatment. After receiving CT-guided percutaneous RFA therapy, the target lesion was effectively controlled and CT values gradually decreased. Besides, no significant changes were observed in the patient's lung function, postoperative complications were experienced by a total of 10 patients, primarily including pneumothorax, infection, lung hollowing. Fortunately, all these complications were successfully managed with appropriate treatment. Following the initial RFA treatment, 31 patients (88.57%) achieved complete ablation, while 6 patients experienced local recurrence. After 6 months of treatment, the ORR and DCR were found to be 68.57% and 82.86% respectively. CT-guided percutaneous RFA has demonstrated favorable safety and efficacy in the treatment of patients with NSCLC at different stages, which represented a promising therapeutic modality.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Ablación por Radiofrecuencia , Tomografía Computarizada por Rayos X , Humanos , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/cirugía , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Masculino , Femenino , Persona de Mediana Edad , Ablación por Radiofrecuencia/métodos , Ablación por Radiofrecuencia/efectos adversos , Anciano , Resultado del Tratamiento , Adulto , Recurrencia Local de Neoplasia , Ablación por Catéter/métodos , Ablación por Catéter/efectos adversos
2.
Materials (Basel) ; 17(13)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38998210

RESUMEN

Vat photopolymerization (VPP), as an additive manufacturing (AM) technology, can conveniently produce ceramic parts with high resolution and excellent surface quality. However, due to the inherent brittleness and low toughness of ceramic materials, manufacturing defect-free ceramic parts remains a challenge. Many researchers have attempted to use carbon fibers as additives to enhance the performance of ceramic parts, but these methods are mostly applied in processes like fused deposition modeling and hot pressing. To date, no one has applied them to VPP-based AM technology. This is mainly because the black carbon fibers reduce laser penetration, making it difficult to cure the ceramic slurry and thus challenging to produce qualified ceramic parts. To address this issue, our study has strictly controlled the amount of carbon fibers by incorporating trace amounts of carbon fiber powder into the original ceramic slurry with the aim to investigate the impact of these additions on the performance of ceramic parts. In this study, ceramic slurries with three different carbon fiber contents (0 wt.%, 0.1 wt.%, 0.2 wt.%, and 0.3 wt.%) were used for additive manufacturing. A detailed comparative analysis of the microstructure, physical properties, and mechanical performance of the parts was conducted. The experimental results indicate that the 3D-printed alumina parts with added carbon fibers show varying degrees of improvement in multiple performance parameters. Notably, the samples prepared with 0.2 wt.% carbon fiber content exhibited the most significant performance enhancements.

3.
Materials (Basel) ; 17(12)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38930342

RESUMEN

Alumina (Al2O3) ceramics are widely used in electronics, machinery, healthcare, and other fields due to their excellent hardness and high temperature stability. However, their high brittleness limits further applications, such as artificial ceramic implants and highly flexible protective gear. To address the limitations of single-phase toughening in Al2O3 ceramics, some researchers have introduced a second phase to enhance these ceramics. However, introducing a single phase still limits the range of performance improvement. Therefore, this study explores the printing of Al2O3 ceramics by adding two different phases. Additionally, a new gradient printing technique is proposed to overcome the limitations of single material homogeneity, such as uniform performance and the presence of large residual stresses. Unlike traditional vat photopolymerization printing technology, this study stands out by generating green bodies with varying second-phase particle ratios across different layers. This study investigated the effects of different contents of sepiolite fiber (SF) and 316L stainless steel (SS) on various aspects of microstructure, phase composition, physical properties, and mechanical properties of gradient-printed Al2O3. The experimental results demonstrate that compared to Al2O3 parts without added SF and 316L SS, the inclusion of these materials can significantly reduce porosity and water absorption, resulting in a denser structure. In addition, the substantial improvements, with an increase of 394.4% in flexural strength and an increase of 316.7% in toughness, of the Al2O3 components enhanced by incorporating SF and 316L SS have been obtained.

4.
Chem Sci ; 15(14): 5113-5122, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38577357

RESUMEN

Controlling the transformation of versatile and reactive allenes is a considerable challenge. Herein, we report an efficient silylboronate-mediated cross-coupling reaction of organic fluorides with allenes to construct a series of sterically demanding α-ethynyl-containing all-carbon quaternary centers (ACQCs), using catalyst-free silyl-radical-relay reactions to selectively functionalize highly inert C-F bonds in organic fluorides. The key to the success of this transformation lies in the radical rearrangement of an in situ-generated allenyl radical to form a bulky tertiary propargyl radical; however, the transformation does not show efficiency when using the propargyl isomer directly. This unique reaction enables the cross-coupling of a tertiary carbon radical center with a C(sp2)-F bond or a benzylic C(sp3)-F bond. α-Ethynyl-containing ACQCs with (hetero)aromatic substituents and benzyl were efficiently synthesized in a single step using electronically and sterically diverse organic fluorides and allenes. The practical utility of this protocol is showcased by the late-stage functionalization of bioactive molecules and the modification of a liquid crystalline material.

5.
Front Neurosci ; 18: 1346635, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38318465

RESUMEN

Circadian rhythm sleep-wake disorders (CRSWDs) are becoming increasingly common in modern societies due to lifestyle changes. The detrimental effects of CRSWDs on sleep and psychological health have attracted considerable attention recently. Alternative remedies for the treatment of CRSWDs have also gained attention in recent years owing to the limitations of medications. Several in vivo and clinical investigations have shown that acupuncture, one of the most important components of traditional Chinese medicine (TCM), has been shown to modulate sleep-related circadian rhythms. Owing to the lack of research on the mechanism and effectiveness of acupuncture in treating CRSWDs, clinical applications of acupuncture have not gained popularity. This paper reviews the acupuncture methods, acupoint selection, and biochemical indicators supplied by in vivo and clinical studies to explore the effectiveness of acupuncture, and summarizes the circadian rhythm mechanisms and the acupuncture characteristics on circadian rhythm. The neurochemical mechanisms linked to acupuncture in treating CRSWDs are also outlined from the perspective of the central and peripheral biological clocks. Lastly, the inadequacy of previous studies on CRSWDs and conflicting results regarding acupuncture are explored and future research directions are envisioned.

6.
Food Chem ; 444: 138690, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38354654

RESUMEN

The identification of baijiu vintage is crucial for quality assessment and economic value determination. However, its complex composition and multifaceted influences pose significant technical challenges, necessitating research into its aging mechanisms and the development of related identification methods. This study utilized Chemometrics in conjunction with GC × GC-TOFMS for Baijiu Vintage identification. Data compression achieved a reduction of over 1000-fold without compromising key information, enabling analysis on many samples and get their changing regular in a big matrix by MCR. Subsequently, MCR-ALS facilitated the extraction of physical and chemical meaningful information related to baijiu vintage. Key MCR principal components suitable for qualitative and quantitative assessments were selected using CARS-PLS. The regression model demonstrated errors of less than one year. Furthermore, a PLS-DA model provided 30 MCR principal components as potential markers. The research results provide technical support for baijiu vintage identification and lay the groundwork for studying the changing patterns of flavor compounds in baijiu.


Asunto(s)
Quimiometría , Cromatografía de Gases y Espectrometría de Masas/métodos , Análisis de los Mínimos Cuadrados
7.
Adv Mater ; 36(3): e2306993, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37851922

RESUMEN

Conventional coupling agents (such as polyvinylpyrrolidone, methylcellulose, and polyurethane) are unable to efficiently transport drugs through the skin's dual barriers (the epidermal cuticle barrier and the basement membrane barrier between the epidermis and dermis) when exposed to ultrasound, hindering deep and noninvasive transdermal drug delivery. In this study, nanobubbles prepared by the double emulsification method and aminated hyaluronic acid are crosslinked with aldehyde-based hyaluronic acid by dynamic covalent bonding through the Schiff base reaction to produce an innovative ultrasound-nanobubble coupling agent. By amplifying the cavitation effect of ultrasound, drugs can be efficiently transferred through the double barrier of the skin and delivered to deep layers. In an in vitro model of isolated porcine skin, this agent achieves an effective penetration depth of 728 µm with the parameters of ultrasound set at 2 W, 650 kHz, and 50% duty cycle for 20 min. Consequently, drugs can be efficiently delivered to deeper layers noninvasively. In summary, this ultrasound nanobubble coupling agent efficiently achieves deep-layer drug delivery by amplifying the ultrasonic cavitation effect and penetrating the double barriers, heralding a new era for noninvasive drug delivery platforms and disease treatment.


Asunto(s)
Ácido Hialurónico , Piel , Porcinos , Animales , Sistemas de Liberación de Medicamentos/métodos , Ultrasonografía , Administración Cutánea , Preparaciones Farmacéuticas
8.
Artículo en Inglés | MEDLINE | ID: mdl-37768793

RESUMEN

We propose a novel and automatic method to model shapes using a small set of discrete developable patches. Central to our approach is using implicit neural shape representation that makes our algorithm independent of tessellation and allows us to obtain the Gaussian curvature of each point analytically. With this powerful representation, we first deform the input shape to be an almost developable shape with clear and sparse salient feature curves. Then, we convert the deformed implicit field to a triangle mesh, which is further cut to disk topology along parts of the sparse feature curves. Finally, we achieve the resulting piecewise developable mesh by alternatingly optimizing discrete developability, enforcing manufacturability constraints, and merging patches. The feasibility and practicability of our method are demonstrated over various shapes. Compared to the state-of-the-art methods, our method achieves a better tradeoff between the number of developable patches and the approximation error.

9.
Sheng Li Xue Bao ; 75(4): 569-574, 2023 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-37583044

RESUMEN

Sleep is an extremely important physiological state to maintain human life. Sleep disorders can not only cause anxiety and depression, but also induce multi-system diseases that seriously affect brain function and physical health. The neuroinflammation is a key pathological process after sleep disorders, which can induce a series of nervous system diseases. In recent years, the role of microglia activation in neuroinflammation has been paid more and more attention and become a research hotspot in this field. The imbalance of the central microenvironment after sleep disorders leads to changes in the activation and polarization of microglia, which triggers neuroinflammatory response. The activation and polarization of microglia in the sleep disorders are regulated by multiple signaling pathways and complex molecular mechanisms. This paper summarizes five signaling pathways of microglia activation in central inflammation induced by sleep disorders, including P2X7 receptor (P2X7R), p38MAPK, Toll-like receptor 4 (TLR4)/NF-κB, JAK/STAT, and α7 nicotinic acetylcholine receptor (α7-nAChR) pathways, in order to provide reference for further research and clinical treatment targets selection of sleep disorders.


Asunto(s)
Enfermedades Neuroinflamatorias , Trastornos del Sueño-Vigilia , Humanos , Microglía/metabolismo , Transducción de Señal/fisiología , FN-kappa B/metabolismo , Inflamación/metabolismo , Trastornos del Sueño-Vigilia/metabolismo
10.
Artículo en Inglés | MEDLINE | ID: mdl-37335785

RESUMEN

We propose a practical method to construct sparse integer-constrained cone singularities with low distortion constraints for conformal parameterizations. Our solution for this combinatorial problem is a two-stage procedure that first enhances sparsity for generating an initialization and then optimizes to reduce the number of cones and the parameterization distortion. Central to the first stage is a progressive process to determine the combinatorial variables, i.e., numbers, locations, and angles of cones. The second stage iteratively conducts adaptive cone relocations and merges close cones for optimization. We extensively test our method on a data set containing 3885 models, demonstrating practical robustness and performance. Our method achieves fewer cone singularities and lower parameterization distortion than state-of-the-art methods.

11.
Chem Sci ; 14(16): 4248-4256, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37123196

RESUMEN

Although the cross-couplings of aryl halides with diarylmethanes are mostly achieved by transition-metal catalysis, aryl fluorides are rarely used as coupling partners owing to the high inertness of C-F bonds. Herein, we describe the efficient silylboronate-mediated cross-coupling reaction of aryl fluorides with arylalkanes under transition-metal-free, room-temperature conditions. The combination of silylboronate and KO t Bu is critical for driving a radical process via the cleavage of C-F and C-H bonds in two appropriate coupling precursors, resulting in a cross-coupling product. This practical cross-coupling protocol is applicable to a wide variety of aryl fluorides with a C(sp2)-F bond. This method can be extended to other coupling partners with a C(sp3)-H bond, including diarylmethanes, diarylethanes, and monoarylalkanes. Many di- and triarylalkanes with tertiary or quaternary carbon centers can be obtained easily in moderate to high yields. We believe that the developed silylboronate-mediated cross-coupling method is a valuable contribution to C-F and C-H activation chemistry.

12.
Nat Commun ; 14(1): 1847, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37012229

RESUMEN

C-N bond cross-couplings are fundamental in the field of organic chemistry. Herein, silylboronate-mediated selective defluorinative cross-coupling of organic fluorides with secondary amines via a transition-metal-free strategy is disclosed. The cooperation of silylboronate and potassium tert-butoxide enables the room-temperature cross-coupling of C-F and N-H bonds, effectively avoiding the high barriers associated with thermally induced SN2 or SN1 amination. The significant advantage of this transformation is the selective activation of the C-F bond of the organic fluoride by silylboronate without affecting potentially cleavable C-O, C-Cl, heteroaryl C-H, or C-N bonds and CF3 groups. Tertiary amines with aromatic, heteroaromatic, and/or aliphatic groups were efficiently synthesized in a single step using electronically and sterically varying organic fluorides and N-alkylanilines or secondary amines. The protocol is extended to the late-stage syntheses of drug candidates, including their deuterium-labeled analogs.

13.
Zootaxa ; 5138(3): 324-338, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-36095833

RESUMEN

Among Scarabaeidae, the phytophagous scarab lineage including Melolonthinae, Cetoniinae, Dynastinae, and Rutelinae is considered important due to its members roles as agricultural pests or pollinators. In this study, the near-complete mitochondrial genomes of seven species from six genera in the phytophagous scarab lineage were newly sequenced: Anomala russiventris (Fairmaire, 1893); Apogonia cf. basalis (Moser, 1915); Apogonia splendida (Boheman, 1858); Coenochilus striatus (Westwood, 1874); Trichogomphus mongol (Arrow, 1908); Sophrops subrugatus (Moser, 1921) and Tetraserica leishanica (Liu, Bai, Yang Ahrens, 2014). The complete mitochondrial genomes from the 6 species include 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and 1 control region, which have a highly conserved gene arrangement, except for Tr. mongol with the rearrangement of 2 tRNA genes (tRNA-Ile and tRNA-Gln), which is a potential identified subfamily-level character of Dynastinae. In order to test whether the mitogenomic data are suited for high-level phylogenetic inferences, the substitution saturation and heterogeneity were analyzed. The results showed no sign that the phylogenetic inferences were biased by substitution saturation or the low heterogeneity of the sequence composition for most pairwise comparisons between the sequences for the entire dataset (13 PCGs) and the amino acids dataset (13 PCGs_AA). Based on the combined data of 13 PCGs and 13 PCGs_AA from the mitogenomes of 37 taxa, the phylogeny of the phytophagous lineage was explored using RAxML and Bayesian methods. The results confirmed that Cetoniinae, Rutelinae, and Dynastinae are monophyletic, and that the latter two are sister groups. Melolonthinae is a paraphyletic group, and its tribes, Diplotaxini, Euchirini, Melolonthini, Rhizotrogini, and Sericini, are a monophyletic group. The subfamily rank of Dynastinae and the tribe rank of Anomalini and Adoretini are supported.


Asunto(s)
Escarabajos , Genoma Mitocondrial , Animales , Teorema de Bayes , Escarabajos/genética , Filogenia , ARN de Transferencia/genética
14.
Commun Biol ; 5(1): 777, 2022 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-35933440

RESUMEN

Conglobation is an adaptive behaviour occurring independently in various animal groups. Here, we study the evolution of conglobation in Ceratocanthinae, a beetle group with the ability to roll three body segments into a tight ball. It is here implied that this ability evolved only once in the Mesozoic. Evidence is offered suggesting that the high defensive strength of Ceratocanthinae is due not only to the spherical body shape but also to the thickness and stronger mechanical properties of the dorsal cuticle. We further validate five adaptive characters including the allometrically thickened body wall and find that the specific adaptation of different body segments are likely separate evolutionary events. Finally, we propose an "attackers stress" hypothesis to explain the origin of conglobation behaviours. This work contributes to understanding how and why conglobation behaviour may have evolved in this group.


Asunto(s)
Evolución Biológica , Escarabajos , Adaptación Fisiológica , Animales
15.
Org Lett ; 24(28): 5084-5089, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35797451

RESUMEN

Potassium-base-mediated defluoroetherification of aryl and heteroaryl fluorides with alkoxyboronic acid pinacol esters under transition-metal-free conditions is reported. This protocol efficiently and safely provides a wide variety of aryl ethers in high yields without using metal catalysts, specific ligands, and harsh conditions to selectively forge Csp2-O bonds via the Csp2-F cleavage. This method can be applied to the late-stage etherification of structurally complex Csp2-fluorides and bioactive alcohols, such as ß-estradiol, calciferol, and tocopherol.

16.
Int J Biol Macromol ; 201: 20-28, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-34998870

RESUMEN

The administration of nanodrugs can lead to metabolism related systemic toxicity due to the use of inert carriers in large quantities. Carrier materials that offer therapeutic effects are therefore a promising means of addressing this limitation. Herein, a hyaluronate-based nanocarrier was prepared from hyaluronic acid (HA) and solanesol. Solanesyl thiosalicylate (STS) derived from solanesol has certain antitumor effects and was used to modify HA. The conjugate (HA-STS) self-assembled into nanoparticles acting as a drug carrier. The synthesis of the conjugates was confirmed by 1H NMR spectroscopy. Doxorubicin (DOX) was loaded into the HA-STS nanoparticles with a relatively high content of 6.0%. pH-sensitive drug release behavior was achieved by introducing a hydroazone bond between STS and HA. A cytotoxicity assay indicated that the blank nanoparticles had an antitumor effect, which was enhanced by loading with an additional drug. Moreover, in vivo antitumor experiments indicated that the HA-STS-DOX showed superior tumor inhibition compared with free DOX, as well as lower cardiotoxicity and hepatotoxicity, demonstrating the advantages of the bioactive drug vehicles in cancer therapy.


Asunto(s)
Nanopartículas , Neoplasias , Doxorrubicina , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Humanos , Ácido Hialurónico/química , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Terpenos/química
17.
Front Chem ; 9: 771473, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34760872

RESUMEN

The defluorosilylation of aryl fluorides to access aryl silanes was achieved under transition-metal-free conditions via an inert C-F bond activation. The defluorosilylation, mediated by silylboronates and KOtBu, proceeded smoothly at room temperature to afford various aryl silanes in good yields. Although a comparative experiment indicated that Ni catalyst facilitated this transformation more efficiently, the transition-metal-free protocol is advantageous from a green chemistry perspective.

18.
Environ Toxicol ; 36(12): 2541-2550, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34499403

RESUMEN

Bergenin is a C-glucoside of 4-O-methyl gallic acid with a variety of biological activities, such as antioxidant and anti-inflammatory. Herein, we investigated the involvement of bergenin in the protective effect against H2 O2 -induced oxidative stress and apoptosis in human nucleus pulposus cells (HNPCs) and the underlying mechanisms. HNPCs were cotreated with various concentrations of bergenin and 200 µM H2 O2 for 24 h. Cell viability was detected by Cell Counting Kit-8 and lactate dehydrogenase release assays. Reactive oxygen species (ROS) was evaluated utilizing 2',7'-dichlorofluorescein-diacetate. Superoxide dismutase (SOD) and catalase (CAT) activities and glutathione (GSH) levels were measured to assess oxidative stress. Apoptosis was evaluated using terminal deoxynucleotidyl transferase dUTP nick end labeling and caspase-3/7 activity assays. Expression of protein was determined by western blotting. Results indicated that treatment with bergenin significantly alleviated H2 O2 -induced viability reduction and ROS overproduction in HNPCs in a dose-dependent manner. Bergenin alleviated H2 O2 -induced oxidative stress in HNPCs by increased activity of superoxide dismutase and level of glutathione peroxidase. H2 O2 -induced apoptosis and activity of caspase-3/7 were also suppressed by bergenin treatment in HNPCs. Western blotting showed that H2 O2 -induced decrease in expression of peroxisome proliferator-activated receptor γ (PPAR-γ) and increase in nuclear factor κB (NF-κB) were inhibited by bergenin. However, the inhibitory effect of bergenin on H2 O2 -induced viability reduction, oxidative stress and apoptosis were noticeably abrogated in PPAR-γ knockdown HNPCs. In conclusion, our results indicated that bergenin alleviates H2 O2 -induced oxidative stress and apoptosis in HNPCs by activating PPAR-γ and suppressing NF-κB pathway.


Asunto(s)
FN-kappa B , Núcleo Pulposo , Apoptosis , Benzopiranos , FN-kappa B/metabolismo , Núcleo Pulposo/metabolismo , Estrés Oxidativo , PPAR gamma/genética , PPAR gamma/metabolismo , Especies Reactivas de Oxígeno
19.
Nat Commun ; 12(1): 3749, 2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34145264

RESUMEN

A regioselective carbosilylation of alkenes has emerged as a powerful strategy to access molecules with functionalized silylated alkanes, by incorporating silyl and carbon groups across an alkene double bond. However, to the best of our knowledge, organic fluorides have never been used in this protocol. Here we disclose the catalyst-free carbosilylation of alkenes using silyl boronates and organic fluorides mediated by tBuOK. The main feature of this transformation is the selective activation of the C-F bond of an organic fluoride by the silyl boronate without undergoing potential side-reactions involving C-O, C-Cl, heteroaryl-CH, and even CF3 groups. Various silylated alkanes with tertiary or quaternary carbon centers that have aromatic, hetero-aromatic, and/or aliphatic groups at the ß-position are synthesized in a single step from substituted or non-substituted aryl alkenes. An intramolecular variant of this carbosilylation is also achieved via the reaction of a fluoroarene with a ω-alkenyl side chain and a silyl boronate.

20.
Int J Bioprint ; 7(2): 346, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33997435

RESUMEN

Poly-L-lactic acid (PLLA) lacks osteogenic activity, which limits its application in bone repair. Zinc (Zn) is widely applied to strengthen the biological properties of polymers due to its excellent osteogenic activity. In the present study, Zn-doped mesoporous silica (Zn-MS) particles were synthesized by one-pot hydrothermal method. Then, the particles were induced into PLLA scaffolds prepared by selective laser sintering technique, aiming to improve their osteogenic activity. Our results showed that the synthesized particles possessed rosette-like morphology and uniform mesoporous structure, and the composite scaffold displayed the sustained release of Zn ion in a low concentration range, which was attributed to the shield effect of the PLLA matrix and the strong bonding interaction of Si-O-Zn. The scaffold could evidently promote osteogenesis differentiation of mouse bone marrow mesenchymal stem cells by upregulating their osteogenesis-related gene expression. Besides, Zn-MS particles could significantly increase the compressive strength of the PLLA scaffold because of their rosette-like morphology and mesoporous structure, which can form micromechanical interlocking with the PLLA matrix. The Zn-MS particles possess great potential to improve various polymer scaffold properties due to their advantageous morphology and physicochemical properties.

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