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1.
BMC Plant Biol ; 24(1): 334, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664603

RESUMEN

BACKGROUND: B-box (BBX) proteins are a type of zinc finger proteins containing one or two B-box domains. They play important roles in development and diverse stress responses of plants, yet their roles in wheat remain unclear. RESULTS: In this study, 96 BBX genes were identified in the wheat genome and classified into five subfamilies. Subcellular localization prediction results showed that 68 TaBBXs were localized in the nucleus. Protein interaction prediction analysis indicated that interaction was one way that these proteins exerted their functions. Promoter analysis indicated that TaBBXs may play important roles in light signal, hormone, and stress responses. qRT-PCR analysis revealed that 14 TaBBXs were highly expressed in seeds compared with other tissues. These were probably involved in seed dormancy and germination, and their expression patterns were investigated during dormancy acquisition and release in the seeds of wheat varieties Jing 411 and Hongmangchun 21, showing significant differences in seed dormancy and germination phenotypes. Subcellular localization analysis confirmed that the three candidates TaBBX2-2 A, TaBBX4-2 A, and TaBBX11-2D were nuclear proteins. Transcriptional self-activation experiments further demonstrated that TaBBX4-2A was transcriptionally active, but TaBBX2-2A and TaBBX11-2D were not. Protein interaction analysis revealed that TaBBX2-2A, TaBBX4-2A, and TaBBX11-2D had no interaction with each other, while TaBBX2-2A and TaBBX11-2D interacted with each other, indicating that TaBBX4-2A may regulate seed dormancy and germination by transcriptional regulation, and TaBBX2-2A and TaBBX11-2D may regulate seed dormancy and germination by forming a homologous complex. CONCLUSIONS: In this study, the wheat BBX gene family was identified and characterized at the genomic level by bioinformatics analysis. These observations provide a theoretical basis for future studies on the functions of BBXs in wheat and other species.


Asunto(s)
Germinación , Familia de Multigenes , Latencia en las Plantas , Proteínas de Plantas , Triticum , Triticum/genética , Triticum/fisiología , Latencia en las Plantas/genética , Germinación/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Semillas/genética , Semillas/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Simulación por Computador , Filogenia
2.
J Org Chem ; 89(10): 6783-6792, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38661714

RESUMEN

Tetrazoles and their derivatives are essential for compound synthesis due to their versatility, effectiveness, stability in air, and cost-efficiency. This has stimulated interest in developing techniques for their production. In this work, four compounds, tetrazolo[1,5-c]pyrimidin-5-amine (1), N-(4-azidopyrimidin-2-yl)nitramide (2), tetrazolo[1,5-c]pyrimidin-5(6H)-one (3), and tetrazolo[1,5-a]pyrimidin-5-amine (4), were obtained from commercially available reagents and straightforward synthetic methodologies. These new compounds were characterized by infrared (IR), 13C, and 1H NMR spectroscopy, differential scanning calorimetry (DSC), and single-crystal X-ray diffraction. The solvent, temperature, and electron-donating group (EDG) factors that were responsible for the steering of azido-tetrazole equilibrium in all compounds were also studied. In addition, the detonation performance of the target compounds was calculated by using heats of formation (HOFs) and crystal densities. Hirshfeld surface analysis was used to examine the intermolecular interactions of the four synthesized compounds. The results show that the excellent properties of 1-4 are triggered by ionic bonds, hydrogen bonds, and π-π stacking interactions, indicating that these compounds have the potential to be used in the development of high-performance energetic materials. Additionally, DFT analysis is in support of experimental results, which proved the effect of different factors that can influence the azido-tetrazole equilibrium in the synthesized pyrimidine derivatives in the solution.

3.
Bioorg Chem ; 140: 106822, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37666111

RESUMEN

Pyrimidine which is an important constituent of the genetic material of deoxyribonucleic acid, is identified with a large number of biological activities. Based on this, pyrimidine-derived Schiff bases (1-6) of hydroxy-1-naphthaldehyde were synthesized by using the condensation method. In addition, the molecular docking studies against topoisomerase II DNA gyrase, human hematopoietic cell kinase, urate oxidase from Aspergillus flavus, and cyclin-dependent kinase 8 to explore the antibacterial, antioxidant, antifungal, and anticancer properties respectively and binding affinities through bioinformatics approaches to determine the interaction among active molecules with the receptor. Hence, the computational docking analyses identified that all synthesized pyrimidine Schiff bases (1-6) are active and exhibited better binding affinities as compared to the standard drugs. Furthermore, all the prepared materials were characterized by using nuclear magnetic resonance, infrared, and elemental analysis. Additionally, the phase-transition and thermal decomposition temperatures were determined by differential scanning calorimetry and thermo-gravimetric analysis measurements. Moreover, the structures of pyrimidine-derived Schiff bases 1, 2, 3, 4, and 5 were also confirmed by the X-ray single-crystal diffraction technique. The pyrimidine-derived Schiff bases 5 possess significant antibacterial, antioxidant, antifungal, and anticancer agent properties which confirms its promising biological activities over standard drugs.


Asunto(s)
Antifúngicos , Antioxidantes , Humanos , Antifúngicos/farmacología , Simulación del Acoplamiento Molecular , Bases de Schiff/farmacología , Pirimidinas/farmacología , Antibacterianos/farmacología
4.
Small ; 17(34): e2007442, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34278712

RESUMEN

Detrimental lithium polysulfide (LiPS) shuttle effects and sluggish electrochemical conversion kinetics in lithium-sulfur (Li-S) batteries severely hinder their practical application. Separator modification has been extensively investigated as an effective strategy to address above issues. Nevertheless, in the case of functional separators, how to effectively block the LiPSs from diffusion while enabling the rapid Li ion transport remains a challenge. Herein, by using an "oxidation-etching" method, MXene membranes are presented with controllable in-plane pores as interlayer to regulate Li ion transportation and LiPS immobilization. Porous MXene membranes with optimized pore density and size can simultaneously anchor LiPS and ensure fast Li ion diffusion. Consequently, even with pure sulfur cathode, the improved Li-S batteries deliver excellent rate performance up to 2 C with a reversible capacity of 677.6 mAh g-1 and long-term cyclability over 500 cycles at 1 C with a low capacity decay of 0.07% per cycle. This work sheds new insights into the design of high-performance interlayers with manipulated nanochannels and tailored surface chemistry to regulate LiPSs trapping and Li ion diffusion in Li-S batteries.

5.
Inorg Chem ; 60(17): 12847-12854, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34374280

RESUMEN

Understanding of adsorption and kinetic conversion of polysulfide lithium (LiPSs) in Li-S batteries is quite crucial for the design of efficient effective sulfur carriers. Herein, based on the possible interactions with LiPSs, Ce2O2S with unique O-Ce-S bindings is proposed to be used as a promising carrier additive and a 2D Ce2O2S/C composite is synthesized via a one-facile NaCl-template method and subsequent sulfuration under 700 °C. The 2D Ce2O2S/C exhibits a stronger adsorption capability than CeO2/C through the adsorption test for Li2S6. Combined with XPS and DFT results, the superiority is mainly originated from the formation of S-S and Li-S bonds between LiPSs and the lattice S on the surface of Ce2O2S. The 2D Ce2O2S/C composite also exhibits a better catalytic ability than CeO2 according to the change of the free energies of the polysulfides during the discharge process, which coincides with the lower oxidation potential for Li2S2/Li2S transition by cyclic voltammetry. Resultantly, the cathodes using the Ce2O2S/C composite as a carrier manifest an enhanced rate and cycling performances. Hence, our work paves a phenomenon wherein Ce2O2S with O-Ce-S bindings is more beneficial to improve the cycling stability of Li-S batteries than CeO2 containing single Ce-O bonds, which may be also suitable for other kinds of metallic sulfur oxide compounds.

6.
Environ Res ; 197: 111026, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33744265

RESUMEN

Here we developed the functionalized biochar as low-cost and heavy metal-free photocatalysts via a facile iodine doping method, which exhibit efficient adsorption and visible-light-driven photocatalytic degradation of representative organic pollutants, phenol and tetracycline. On one hand, iodine doping elevates the adsorption via creating extra pores, e.g., the adsorbed amounts of phenol by iodine-doped WSP and OSR biochar are increased by 161.8% and 146.3%, respectively, which in turn facilitates the photocatalytic oxidation of the adsorbed pollutants. On the other hand, iodine doping leads to the strong photo-induced excitation and remarkably reduced charge carrier transfer resistance, boosting the photocatalytic activity of iodine-doped biochar by more than 20 orders towards organic pollutants (e.g., phenol) degradation. The systematic analysis of reactive species reveals the active roles of O2-, H2O2, 1O2, OH, electrons, and holes in photocatalytic process and identifies O2- to be the major contributor. This work affords a facile approach to generating porous and visible-light-driven photocatalyst from biomass for efficient adsorbing and degrading organic pollutants, opening up an avenue to turn biowaste into biomaterials for sustainable environmental remediation.


Asunto(s)
Doping en los Deportes , Contaminantes Ambientales , Yodo , Adsorción , Catálisis , Carbón Orgánico , Peróxido de Hidrógeno , Luz
7.
Angew Chem Int Ed Engl ; 60(47): 25122-25127, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34637181

RESUMEN

K metal is the optimal anode for K-ion batteries because of its high capacity and low operating potential, but it suffers from fast capacity fading and safety issues due to an unstable solid electrolyte interphase (SEI) and continuous K-dendrite growth. Herein, to obtain promising potassium-metal batteries, a 3D polyvinyl-alcohol (PVA)-borax layer is designed, which enables a dendrite-free K-plating/stripping process. The protective layer possesses good wettability, high K-ion diffusivity, and good structural stability, which enables a "uniform and underneath plating" behavior, therefore exhibiting a stable electrochemical performance. As a result, Cu current collector with PVA-borax (PVA-borax@Cu) exhibits a stable cycling lifetime for 700 h at 0.5 mA cm-2 and 500 h at 1 mA cm-2 at 10 % depth of discharge (DOD) without dendrite formation. Even at a high utilization of 25 % DOD and 50 % DOD, the PVA-borax@Cu shows a stable cycle for 180 h and 100 h, respectively.

8.
Environ Sci Technol ; 54(1): 537-549, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31830789

RESUMEN

A novel and efficient 3D biohybrid photocatalyst, defective MoS2 nanosheets encapsulated carbonized rape pollen, was fabricated and applied to water disinfection. The rape pollen-MoS2 (PM) biohybrid showed excellent dispersibility, high stability, and efficient charge-carrier separation and migration ability, resulting in the highly enhanced photocatalytic inactivation performance toward various waterborne bacteria under different light sources. The inactivation mechanisms were systematically investigated. Reactive species (RSs), including electrons, holes, and reactive oxygen species (•O2- and •OH), played major roles in inactivating bacteria. The antioxidant system of bacteria exhibited a self-protection capacity by eliminating the photogenerated RSs from PM biohybrid at the early stage of inactivation. With the accumulation of RSs, the cell membrane and membrane-associated functions were destroyed, as suggested by the collapse of cell envelope and subsequent loss of cell respiration and ATP synthesis capacity. The microscopic images further confirmed the destruction of the bacterial membrane. After losing the membrane barrier, the oxidation of cytoplasmic proteins and lipids caused by invaded RSs occurred readily. Finally, the leakage of DNA and RNA announced the irreversible death of bacteria. These results indicated that the bacterial inactivation began with the membrane rupture, followed by the oxidation and leakage of intracellular substances. This work not only provided a new insight into the combination of semiconductors with earth-abundant biomaterials for fabricating high-performance photocatalysts, but also revealed the underlying mechanisms of photocatalytic bacterial inactivation in depth.


Asunto(s)
Molibdeno , Bacterias , Brassica napus , Catálisis , Luz , Polen
9.
Nano Lett ; 19(1): 488-493, 2019 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-30525684

RESUMEN

We investigate black phosphorus by time- and angle-resolved photoelectron spectroscopy. The electrons excited by 1.57 eV photons relax down to a conduction band minimum within 1 ps. Despite the low band gap value, no relevant amount of carrier multiplication could be detected at an excitation density 3-6 × 1019 cm-3. In the thermalized state, the band gap renormalization is negligible up to a photoexcitation density that fills the conduction band by 150 meV. Astonishingly, a Stark broadening of the valence band takes place at an early delay time. We argue that electrons and holes with a high excess energy lead to inhomogeneous screening of near surface fields. As a consequence, the chemical potential is no longer pinned in a narrow impurity band.

10.
J Am Chem Soc ; 139(26): 8897-8904, 2017 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-28618776

RESUMEN

Porous materials such as covalent organic frameworks (COFs) are good candidates for molecular sieves due to the chemical diversity of their building blocks, which allows fine-tuning of their chemical and physical properties by design. Tailored synthesis of inherently functional building blocks can generate framework materials with chemoresponsivity, leading to controllable functionalities such as switchable sorption and separation. Herein, we demonstrate a chemoselective, salicylideneanilines-based COF (SA-COF), which undergoes solvent-triggered tautomeric switching. This is unique compared to solid-state salicylideneanilines' counterpart, which typically requires high energy input such as photo or thermal activation to trigger the enol-keto tautomerisim and cis-trans isomerization. Accompanying the tautomerization, the ionic properties of the COF can be tuned reversibly, thus forming the basis of size-exclusion, selective ionic binding or chemoseparation in SA-COF demonstrated in this work.

11.
J Am Chem Soc ; 139(29): 10133-10141, 2017 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-28671465

RESUMEN

Sulfur is an attractive cathode material for next-generation lithium batteries due to its high theoretical capacity and low cost. However, dissolution of its lithiated product (lithium polysulfides) into the electrolyte limits the practical application of lithium sulfur batteries. Here we demonstrate that sulfur particles can be hermetically encapsulated by leveraging on the unique properties of two-dimensional materials such as molybdenum disulfide (MoS2). The high flexibility and strong van der Waals force in MoS2 nanoflakes allows effective encapsulation of the sulfur particles and prevent its sublimation during in situ TEM studies. We observe that the lithium diffusivities in the encapsulated sulfur particles are in the order of 10-17 m2 s-1. Composite electrodes made from the MoS2-encapsulated sulfur spheres show outstanding electrochemical performance, with an initial capacity of 1660 mAh g-1 and long cycle life of more than 1000 cycles.

12.
Inorg Chem ; 55(19): 9892-9897, 2016 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-27612093

RESUMEN

A networked spin cage comprising infinite CoII6L4 cages arrays (where Co = Co(NCS)2 and L = 1,3,5-tri-(4-pyridyl)-verdazal radical) is synthesized and found to exhibit tunable magnetic and electrochemical properties via inclusion of guests. SQUID investigation reveals the coexistence of ferromagnetic and anti-ferromagnetic interactions between the Co(II) ion center and radical ligands. Inclusion of electron-deficient guests (e.g., tetracyanoethylene) dramatically enhances spin concentration and increases anti-ferromagnetic interactions due to the formation of charge-transfer complex between the host and the guest. In addition, introduction of electron-rich guests (e.g., tetrathiafulvalene) into the networked spin cages doubles the capacity for binding the lithium ions.

13.
Langmuir ; 30(12): 3538-47, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24568738

RESUMEN

Spectroscopic (XPS, ToF-SIMS) and microscopic (SEM, AFM) analytical methods have been applied to iron oxide (∼Fe2O3) using a thin film approach to bring new insight into the aging mechanisms of conversion-type anode materials for lithium-ion batteries. The results show that repeated lithiation/delithiation causes both chemical and morphological modifications affecting the electrochemical performance. The SEI layer formed by reductive decomposition of the electrolyte remains stable in composition (mostly Li2CO3) but irreversibly thickens upon multicycling. Irreversible swelling of the material accompanied by penetration of the SEI layer and accumulation of non-deconverted material in the bulk of the oxide thin film occurs upon repeated conversion/deconversion. After initial pulverization of the thin film microstructure, grain growth and aggregation are promoted by multicycling. This leads to capacity increase in the first few cycles, but upon further cycling volume expansion and accumulation of non-deconverted material lead to deterioration of the electrode performances.

14.
ACS Appl Mater Interfaces ; 16(5): 5989-5998, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38271587

RESUMEN

In recent years, solid electrolytes (SEs) have been developed a lot due to the superior safety of solid-state batteries (SSBs) upon liquid electrolyte-based commercial batteries. Among them, garnet-type Li7La3Zr2O12 (LLZO) is one of the few SEs that is stable to lithium anode with high Li+ conductivity and the feasibility of preparation under ambient air, which makes it a promising candidate for fabricating SSBs. However, high sintering temperature (>1200 °C) prevents its large-scale production, further hindering its application. In this work, the Li5AlO4 sintering aid is proposed to decrease the sintering temperature and modify the grain boundaries of LLZO ceramics. Li5AlO4 generates in situ Li2O atmosphere and molten Li-Al-O compounds at relatively low temperatures to facilitate the gas-liquid-solid material transportation among raw LLZO grains, which decreases the densification temperature over 150 °C and strengthens the grain boundaries against lithium dendrites. As an example, Ta-doped LLZO ceramics without excessive Li sintered with 2 wt % Li5AlO4 at 1050 °C delivered high relative density > 94%, an ionic conductivity of 6.7 × 10-4 S cm-1, and an excellent critical current density (CCD) of 1.5 mA cm-2 at room temperature. In comparison, Ta-doped LLZO with 15% excessive Li sintered at 1200 °C delivered low relative density < 89%, a low ionic conductivity of ∼2 × 10-4 S cm-1, and a poor CCD of 0.5 mA cm-2. Li symmetric cells and Li-LFP full cells fabricated with Li5AlO4-assised ceramics were stably cycled at 0.2 mA cm-2 over 2000 h and at 0.8C over 100 cycles, respectively.

15.
Chem Commun (Camb) ; 59(87): 13018-13021, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37842776

RESUMEN

One of the most common problems with sulfide solid-state electrolytes is weak water stability. We report a re-sintering method to recover the ionic conductivity of argyrodite Li5.4PS4.4Cl1.6 solid-state electrolyte, which has been exposed to moisture for 10 h, from 1.06 to 6.97 mS cm-1.

16.
ACS Appl Mater Interfaces ; 15(30): 36289-36300, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37470362

RESUMEN

NASICON-type Li1.3Al0.3Ti1.7(PO4)3 (LATP) has attracted a lot of attention because of its high ionic conductivity and stability to air and moisture. However, the size effect of LATP primary particles on ionic conductivity is ignored. In this study, different sizes of LATP particles are prepared to investigate the morphology, relative density, and ionic conductivity of the LATP solid electrolyte. The influences of particle size and sintering temperature on the microstructure, phase composition, and electrical properties of LATP ceramics were systematically studied. The medium-sized LATP particle (2 µm) presents a great microstructure with a high relative density of over 97%, the highest ionic conductivity of 6.7 × 10-4 S cm-1, and an activation energy of 0.418 eV. The Li-Li symmetric cells and Li-LFP batteries delivering good electrochemical performance were fabricated with highly conductive LATP ceramics. These results make significant strides in elucidating the relationship between the particle sizes of LATP and its electrochemical performance.

17.
ACS Appl Mater Interfaces ; 15(4): 5345-5356, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36657037

RESUMEN

Solid-state batteries based on a metallic Li anode and nonflammable solid electrolytes (SEs) are anticipated to achieve high energy and power densities with absolute safety. In particular, cubic garnet-type Nb-doped Li7La3Zr2O12 (Nb-LLZO) SEs possess superior ionic conductivity, are feasible to prepare under ambient conditions, have strong thermal stability, and are of low cost. However, the interfacial compatibility with Li metal and Li dendrite hazards still hinder the applications of Nb-LLZO. Herein, a quick and efficient solution was applied to address this issue, generating a nano-Li3PO4 pre-reduction layer from the reaction of H3PO4 with the ion-exchanged passivation layer (Li2CO3/LiOH) on the surface of Nb-LLZO. A lithiophilic, electrically insulating interlayer is in situ created when the Li3PO4 modified layer interacts with molten Li, successfully preventing the reduction of Nb5+. The interlayer, which mostly consists of Li3P and Li3PO4, also has a high shear modulus and relatively high Li+ conductivity, which effectively inhibit the growth of Li dendrites. The Li|Li3PO4|Nb-LLZO|Li3PO4|Li symmetric cells stably cycled for over 5000 h at 0.05 mA cm-2 and over 1000 h at a high rate of 0.15 mA cm-2 without any short circuits. The LiFePO4 and S/C hybrid solid-state batteries using the modified Nb-LLZO electrolyte also demonstrated good electrochemical performances, confirming the practical application of this interfacial engineering in various solid-state battery systems. This work offers an efficient solution to the instability issue between the Nb-LLZO SE and metallic Li anode.

18.
Chem Commun (Camb) ; 59(47): 7220-7223, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37221931

RESUMEN

A novel efficient method is proposed to synthesize a large amount of Li5.4PS4.4Cl1.6 precursor in only 5 minutes with a conductivity of 20 mS cm-1 after sintering, which can replace the common ball-milling method. The ASSBs show excellent electrochemical performance with high loading (20 mg cm-2) and great capacity retention (80% after 200 cycles). This is important for the industrial production of sulfide solid electrolytes for fabricating Ah-level ASSBs.


Asunto(s)
Electrólitos , Litio , Conductividad Eléctrica , Sulfuros
19.
Anal Methods ; 15(42): 5692-5699, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37861716

RESUMEN

Colloidal gold immunoassay is the most widely used method in the field of drug detection. However, this method often has poor quantitative identification ability and low analytical sensitivity, which is not suitable for the analysis of hair poisoning ingredients. In order to solve these limitations, we developed an immunochromatographic test strip for simultaneously screening multiple drugs in this study. This hand-held test strip used fluorescent nanoparticles loaded with lanthanide chelates as the signal carrier of fluorescence reading, and conducted quantitative testing of various drugs based on the competitive immune reaction between the analyte and antigen. Under the optimal conditions, the competition curves of morphine (MOP), methamphetamine (MET) and ketamine (KET) were obtained on a single band. The detection limit (LOD) of this analytical method was 100-1000 times lower than that of colloidal gold test strips. The detection limits of MOP, MET and KET were 0.06 ng mL-1, 0.1 ng mL-1 and 1.0 ng mL-1, respectively. No cross-reaction was observed when morphine, methamphetamine and ketamine were tested simultaneously with this method. And 184 hair samples were tested simultaneously, and the detected amount was very close to the results of LC-MS. The immunochromatographic strip showed good stability in repeated tests, and the coefficient of variation was less than 15%. Fluorescence immunochromatography strips and handheld strip readers have the characteristics of portability, speed, ease of operation and high sensitivity, and may become powerful tools for screening drug abuse in hair in forensic medicine.


Asunto(s)
Ketamina , Elementos de la Serie de los Lantanoides , Metanfetamina , Morfina/análisis , Límite de Detección , Metanfetamina/análisis , Cromatografía de Afinidad/métodos , Oro Coloide/química , Cabello/química
20.
Biomed Mater ; 18(4)2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37144422

RESUMEN

Increased life expectancy has resulted in an increase in osteoporosis incidence worldwide. The coupling of angiogenesis and osteogenesis is indispensable for bone repair. Although traditional Chinese medicine (TCM) exerts therapeutic effects on osteoporosis, TCM-related scaffolds, which focus on the coupling of angiogenesis and osteogenesis, have not yet been used for the treatment of osteoporotic bone defects.Panax notoginsengsaponin (PNS), the active ingredient ofPanax notoginseng, was added to a poly (L-lactic acid) (PLLA) matrix. Osteopractic total flavone (OTF), the active ingredient ofRhizoma Drynariae, was encapsulated in nano-hydroxyapatite/collagen (nHAC) and added to the PLLA matrix. Magnesium (Mg) particles were added to the PLLA matrix to overcome the bioinert character of PLLA and neutralize the acidic byproducts generated by PLLA. In this OTF-PNS/nHAC/Mg/PLLA scaffold, PNS was released faster than OTF. The control group had an empty bone tunnel; scaffolds containing OTF:PNS = 100:0, 50:50, and 0:100 were used as the treatment groups. Scaffold groups promoted new vessel and bone formation, increased the osteoid tissue, and suppressed the osteoclast activity around osteoporotic bone defects. Scaffold groups upregulated the expression levels of angiogenic and osteogenic proteins. Among these scaffolds, the OTF-PNS (50:50) scaffold exhibited a better capacity for osteogenesis than the OTF-PNS (100:0 and 0:100) scaffolds. Activation of the bone morphogenic protein (BMP)-2/BMP receptor (BMPR)-1A/runt-related transcription factor (RUNX)-2signaling pathway may be a possible mechanism for the promotion of osteogenesis. Our study demonstrated that the OTF-PNS/nHAC/Mg/PLLA scaffold could promote osteogenesis via the coupling of angiogenesis and osteogenesis in osteoporotic rats with bone defects, and activating theBMP-2/BMPR1A/RUNX2signaling pathway may be an osteogenesis-related mechanism. However, further experiments are necessary to facilitate its practical application in the treatment of osteoporotic bone defects.


Asunto(s)
Osteogénesis , Osteoporosis , Ratas , Animales , Ingeniería de Tejidos/métodos , Andamios del Tejido , Huesos/metabolismo , Poliésteres/farmacología , Osteoporosis/terapia , Osteoporosis/metabolismo
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