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1.
Nano Lett ; 23(11): 4983-4990, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37212654

RESUMO

To achieve better properties of van der Waals (vdW) devices, vdW heterointerfaces with substrates such as hexagonal boron nitride (h-BN) were introduced to alleviate adverse substrate effects. However, the premature dielectric breakdown and its scale limitation make wider application of h-BN substrates challenging. Here we report a fluoride-based substrate that substantially improves optoelectronic and transport properties of dichalcogenide devices, with enhancement factors comparable to those of h-BN. A model system of wafer-scale fluoride calcium (CaF2) ultrathin films with the preferable growth direction along [111] is prepared by the magnetron sputtering method. Results show that the constructed SnS2/CaF2 and WS2/CaF2 devices exhibit 1 order of magnitude higher than devices based on the SiO2 substrate in electronic mobility and photoresponsivity. Theoretical calculations reveal that devices based on fluoride substrates are immune from the Coulomb impurity scattering by forming quasi-vdW interfaces, exhibiting great potential for high responsivity and mobility of photogenerated carriers in 2D vdW devices.

2.
Angew Chem Int Ed Engl ; 62(11): e202217054, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36571433

RESUMO

Uncovering differences between crystalline and amorphous states in molecular solids would both promote the understanding of their structure-property relationships, as well as inform development of multi-functional materials based on the same compound. Herein, for the first time, we report an approach to leverage crystalline and amorphous states of a zero-dimensional metal-organic complex, which exhibited negative and positive photochromism, due to the competitive chemical routes between photocycloaddition and photogenerated radicals. Furthermore, different polymorphs lead to the on/off toggling of photo-burst movement (photosalient effect), indicating the controllable light-mechanical conversion. Three demos were further constructed to support their application in information encryption and anti-counterfeiting. This work provides the proof-of-concept of a state- and polymorph-dependent photochemical route, paving an effective way for the design of new dynamically responsive systems.

3.
Nano Lett ; 15(8): 5349-57, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26121062

RESUMO

The distance-dependent plasmon coupling between biopolymer tethered gold or silver nanoparticles forms the foundation for the so-called plasmon rulers. While conventional plasmon ruler applications focus on the detection of singular events in the far-field spectrum, we perform in this Letter a ratiometric analysis of the continuous spectral fluctuations arising from thermal interparticle separation variations in plasmon rulers confined to fluid lipid membranes. We characterized plasmon rulers with different DNA tethers and demonstrate the ability to detect and quantify differences in the plasmon ruler potential and tether stiffness. The influence of the nature of the tether (single-stranded versus double-stranded DNA) and the length of the tether is analyzed. The characterization of the continuous variation of the interparticle separation in individual plasmon rulers through optical fluctuation analysis provides additional information about the conformational flexibility of the tether molecule(s) located in the confinement of the deeply subdiffraction limit interparticle gap and enhances the versatility of plasmon rulers as a tool in Biophysics and Nanotechnology.


Assuntos
DNA/química , Ouro/química , Nanopartículas/química , Prata/química , Dimerização , Elasticidade , Dureza , Ressonância de Plasmônio de Superfície
4.
J Aging Soc Policy ; 27(2): 107-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25350715

RESUMO

Currently, in many countries most workers are covered by a national social security benefits program that applies equally in all parts of the country. In China, however, social security old-age benefits are provided in a highly fragmented manner. This article documents the high degree of fragmentation. It discusses both why that has occurred and the effects of the fragmentation on participants. It examines effects of the fragmentation on benefit levels, focusing on variations in the generosity of benefit formulas but also considering other measures of benefit adequacy. Fragmentation is seen to cause differences in benefit levels even within a single city. While the new National Rural Pension Scheme is a major improvement in the provision of retirement security for rural workers, important differences still exist in the social security programs for urban and rural workers.


Assuntos
Assistência a Idosos/organização & administração , Aposentadoria/economia , Previdência Social/organização & administração , Idoso , Agroquímicos , China , Definição da Elegibilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Previdência Social/economia , População Urbana
5.
Adv Funct Mater ; 24(6): 739-746, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30245611

RESUMO

Metallic and dielectric nanoparticles (NPs) have synergistic electromagnetic properties but their positioning into morphologically defined hybrid arrays with novel optical properties still poses significant challenges. A template-guided self-assembly strategy is introduced for the positioning of metallic and dielectric NPs at pre-defined lattice sites. The chemical assembly approach facilitates the fabrication of clusters of metallic NPs with interparticle separations of only a few nanometers in a landscape of dielectric NPs positioned hundreds of nanometers apart. This approach is used to generate two-dimensional interdigitated arrays of 250 nm diameter TiO2 NPs and clusters of electromagnetically strongly coupled 60 nm Au NPs. The morphologydependent near- and far-field responses of the resulting multiscale optoplasmonic arrays are analyzed in detail. Elastic and inelastic scattering spectroscopy in combination with electromagnetic simulations reveal that optoplasmonic arrays sustain delocalized photonic-plasmonic modes that achieve a cascaded E-field enhancement in the gap junctions of the Au NP clusters and simultaneously increase the E-field intensity throughout the entire array.

6.
Nat Commun ; 15(1): 5281, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902239

RESUMO

Long persistent luminescence (LPL) has gained considerable attention for the applications in decoration, emergency signage, information encryption and biomedicine. However, recently developed LPL materials - encompassing inorganics, organics and inorganic-organic hybrids - often display monochromatic afterglow with limited functionality. Furthermore, triplet exciton-based phosphors are prone to thermal quenching, significantly restricting their high emission efficiency. Here, we show a straightforward wet-chemistry approach for fabricating multimode LPL materials by introducing both anion (Br-) and cation (Sn2+) doping into hexagonal CsCdCl3 all-inorganic perovskites. This process involves establishing new trapping centers from [CdCl6-nBrn]4- and/or [Sn2-nCdnCl9]5- linker units, disrupting the local symmetry in the host framework. These halide perovskites demonstrate afterglow duration time ( > 2,000 s), nearly full-color coverage, high photoluminescence quantum yield ( ~ 84.47%), and the anti-thermal quenching temperature up to 377 K. Particularly, CsCdCl3:x%Br display temperature-dependent LPL and time-valve controllable time-dependent luminescence, while CsCdCl3:x%Sn exhibit forward and reverse excitation-dependent Janus-type luminescence. Combining both experimental and computational studies, this finding not only introduces a local-symmetry breaking strategy for simultaneously enhancing afterglow lifetime and efficiency, but also provides new insights into the multimode LPL materials with dynamic tunability for applications in luminescence, photonics, high-security anti-counterfeiting and information storage.

7.
Mater Horiz ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39045671

RESUMO

Ultralong room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) materials provide exciting opportunities for the rational design of persistent luminescence owing to their long-lived excitons. However, conventional rare-earth-based all-inorganic emitters involve high cost and harsh synthesis conditions, and purely organic systems may require complicated synthesis routes and tedious purification. Therefore, it is highly desirable to develop a cost-effective and easily manufacturable method for achieving color-tunable RTP-TADF with a long afterglow. Herein, we demonstrate a rational strategy to introduce different anions (Cl-, Br- and OAc- ions) into a Zn-based metal-organic scaffold, which can improve the crystal rigidity and achieve a well-balanced RTP-TADF. Both theoretical and experimental studies have demonstrated that the adjustment of different anions can effectively modulate the spin-orbit coupling (SOC) and the energy gap of singlet-triplet states (ΔEST) and then tailor the afterglow lifetime. Moreover, we prepared dye-doped metal-organic hybrid glasses with remarkable potential for the color-tunable afterglow. Therefore, this work not only provides a new horizon for modulating crystal and glass states with color/lifetime-tunable persistent luminescence, but also contributes to optical information storage and anti-counterfeiting technology.

8.
Chem Sci ; 15(10): 3625-3632, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38455006

RESUMO

Color-tunable room temperature phosphorescent (RTP) materials have raised wide interest due to their potential application in the fields of encryption and anti-counterfeiting. Herein, a series of CdX2-organic hybrid perovskitoids, (H-apim)CdX3 and (apim)CdX2 (denoted as CdX-apim1 and CdX-apim2, apim = 1-(3-aminopropyl)imidazole, X = Cl, Br), were synthesized using apim with both rigid and flexible groups as ligands, which exhibit naked-eye detectable RTP with different durations and colors (from cyan to red) by virtue of different halogen atoms, coordination modes and the coplanar configuration of flexible groups. Interestingly, CdCl-apim1 and CdX-apim2 both exhibit excitation wavelength-dependent RTP properties, which can be attributed to the multiple excitation of imidazole/apim, the diverse interactions with halogen atoms, and aggregated state of imidazoles. Structural analysis and theoretical calculations confirm that the aminopropyl groups in CdCl-apim1 do not participate in luminescence, while those in CdCl-apim2 are involved in luminescence including both metal/halogen to ligand charge transfer and twisted intramolecular charge transfer. Furthermore, we demonstrate that these perovskitoids can be applied in multi-step anti-counterfeiting, information encryption and smart ink fields. This work not only develops a new type of perovskitoid with full-color persistent luminescence, but also provides new insight into the effect of flexible ligands and halogen engineering on the wide-range modulation of RTP properties.

9.
Theranostics ; 14(10): 3859-3899, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38994021

RESUMO

Osteoporosis is a systemic skeletal disease caused by an imbalance between bone resorption and formation. Current treatments primarily involve systemic medication and hormone therapy. However, these systemic treatments lack directionality and are often ineffective for locally severe osteoporosis, with the potential for complex adverse reactions. Consequently, treatment strategies using bioactive materials or external interventions have emerged as the most promising approaches. This review proposes twelve microenvironmental treatment targets for osteoporosis-related pathological changes, including local accumulation of inflammatory factors and reactive oxygen species (ROS), imbalance of mitochondrial dynamics, insulin resistance, disruption of bone cell autophagy, imbalance of bone cell apoptosis, changes in neural secretions, aging of bone cells, increased local bone tissue vascular destruction, and decreased regeneration. Additionally, this review examines the current research status of effective or potential biophysical and biochemical stimuli based on these microenvironmental treatment targets and summarizes the advantages and optimal parameters of different bioengineering stimuli to support preclinical and clinical research on osteoporosis treatment and bone regeneration. Finally, the review addresses ongoing challenges and future research prospects.


Assuntos
Osseointegração , Osteoporose , Humanos , Osteoporose/terapia , Animais , Espécies Reativas de Oxigênio/metabolismo , Regeneração Óssea , Autofagia , Osso e Ossos/metabolismo , Apoptose , Bioengenharia/métodos
10.
Evol Appl ; 17(6): e13708, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38863828

RESUMO

Age is a significant contributing factor to the occurrence and progression of cardiovascular disease (CVD). Pharmacological treatment can effectively alleviate CVD symptoms caused by aging. However, 90% of the drugs have failed in clinics because of the loss of drug effects or the occurrence of the side effects. One of the reasons is the disparity between animal models used and the actual physiological levels in humans. Therefore, we integrated multiple datasets from single-cell and bulk-seq RNA-sequencing data in rats, monkeys, and humans to identify genes and pathways with consistent/differential expression patterns across these three species. An approach called "Cross-species signaling pathway analysis" was developed to select suitable animal models for drug screening. The effectiveness of this method was validated through the analysis of the pharmacological predictions of four known anti-vascular aging drugs used in animal/clinical experiments. The effectiveness of drugs was consistently observed between the models and clinics when they targeted pathways with the same trend in our analysis. However, drugs might have exhibited adverse effects if they targeted pathways with opposite trends between the models and the clinics. Additionally, through our approach, we discovered four targets for anti-vascular aging drugs, which were consistent with their pharmaceutical effects in literatures, showing the value of this approach. In the end, software was established to facilitate the use of "Cross-species signaling pathway analysis." In sum, our study suggests utilizing bioinformatics analysis based on disease characteristics can help in choosing more appropriate animal models.

11.
Clin Rheumatol ; 43(6): 2061-2077, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38696115

RESUMO

OBJECTIVE: This study aimed to estimate and predict the burden of osteoarthritis (OA) and site-specific OA (hip, knee, hand, and others) from 1990 to 2030 and their attributable risk factors in China. METHOD: Data were obtained from the Global Burden of Diseases 2019. The burden was estimated by analyzing the trends of prevalence, incidence, and disability-adjusted life years (DALY). Population attributable risk (PAR) was calculated to assess the impact of high body mass index (BMI). The prediction from 2020 to 2030 was implemented by Bayesian age-period-cohort analysis. RESULTS: In China, prevalent cases, DALY, and incident cases of OA increased to 132.81 million, 4.72 million, and 10.68 million, respectively. Age-standardized rates (ASRs) of prevalence, DALYs, and incidence increased for OA and site-specific OA, especially for hip OA. Site-specific OA showed different susceptible peaking ages, and the burden for those over 50 years old became serious. Female preference existed in the trends for knee OA but not in those for hip, hand, and other OA. PARs of high BMI continued to increase, impacting knee OA more than hip OA and showing female preference. In the next decade, incident cases for OA and site-specific OA will continue to increase, despite that the ASR of OA incidence will decrease. CONCLUSIONS: OA and site-specific OA remain huge public health challenges in China. The burden of OA and site-specific OA is increasing, especially among people over 50 years old. Health education, exercise, and removing modifiable risk factors contribute to alleviate the growing burden. Key Points • In China, the burden of osteoarthritis and site-specific osteoarthritis (hip, knee, hand, and others) as well as the Risk Factor (high body mass index) increased greatly from 1990 to 2019. • It is estimated that incident cases for OA and site-specific OA will continue to increase, despite that the ASR of OA incidence will decrease.


Assuntos
Osteoartrite , Humanos , China/epidemiologia , Feminino , Fatores de Risco , Pessoa de Meia-Idade , Masculino , Prevalência , Idoso , Osteoartrite/epidemiologia , Incidência , Adulto , Índice de Massa Corporal , Osteoartrite do Joelho/epidemiologia , Efeitos Psicossociais da Doença , Anos de Vida Ajustados por Deficiência , Adulto Jovem , Carga Global da Doença/tendências , Anos de Vida Ajustados por Qualidade de Vida , Adolescente , Osteoartrite do Quadril/epidemiologia , Idoso de 80 Anos ou mais , Teorema de Bayes
12.
Bioact Mater ; 34: 181-203, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38235308

RESUMO

Supramolecular peptide nanofiber hydrogels are emerging biomaterials for tissue engineering, but it is difficult to fabricate multi-functional systems by simply mixing several short-motif-modified supramolecular peptides because relatively abundant motifs generally hinder nanofiber cross-linking or the formation of long nanofiber. Coupling bioactive factors to the assembling backbone is an ideal strategy to design multi-functional supramolecular peptides in spite of challenging synthesis and purification. Herein, a multi-functional supramolecular peptide, P1R16, is developed by coupling a bioactive factor, parathyroid hormone related peptide 1 (PTHrP-1), to the basic supramolecular peptide RADA16-Ⅰ via solid-phase synthesis. It is found that P1R16 self-assembles into long nanofibers and co-assembles with RADA16-Ⅰ to form nanofiber hydrogels, thus coupling PTHrP-1 to hydrogel matrix. P1R16 nanofiber retains osteoinductive activity in a dose-dependent manner, and P1R16/RADA16-Ⅰ nanofiber hydrogels promote osteogenesis, angiogenesis and osteoclastogenesis in vitro and induce multi-functionalized osteoregeneration by intramembranous ossification and bone remodeling in vivo when loaded to collagen (Col) scaffolds. Abundant red blood marrow formation, ideal osteointegration and adapted degradation are observed in the 50% P1R16/Col scaffold group. Therefore, this study provides a promising strategy to develop multi-functional supramolecular peptides and a new method to topically administrate parathyroid hormone or parathyroid hormone related peptides for non-healing bone defects.

13.
Small ; 9(6): 876-84, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23180691

RESUMO

The use of nanoparticles (NPs) in biomedical applications creates a need for appropriate model systems to systematically investigate NP-membrane interactions under well-defined conditions. Black lipid membranes (BLMs) are free-floating membranes with defined composition that are ideally suited for characterizing NP-membrane interactions free of any potential perturbation through a supporting substrate. Herein, arrays of microfabricated BLMs are integrated into a chip-based platform that is compatible with high-speed optical NP tracking. This system is used to investigate the lateral diffusion of 40 nm gold spheres tethered to biotinylated lipids through antibody-functionalized ligands (single-stranded DNA or polyethylene glycol). Although the NPs show an almost free and ergodic diffusion, their lateral motion is subject to substantial drag at the membrane surface, which leads to systematically smaller diffusion coefficients than those obtained for lipids in the membrane through fluorescence recovery after photobleaching. The lateral mobility of the NPs is influenced by the chemical composition and salt concentration at the NP-membrane interface, but is independent of the ligand density in the membrane. Together with the observation that nanoprisms, which have a larger relative contact area with the membrane than spherical NPs, show an even slower diffusion, these findings indicate that the lateral mobility of NPs tethered in close vicinity to a membrane is significantly reduced by the friction at the NP-membrane interface.


Assuntos
Dispositivos Lab-On-A-Chip , Membranas Artificiais , Nanopartículas , DNA de Cadeia Simples/química , Fotodegradação , Polietilenoglicóis/química
14.
Mater Today Bio ; 23: 100846, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37953757

RESUMO

3D bioprinting technology is widely used to fabricate various tissue structures. However, the absence of vessels hampers the ability of bioprinted tissues to receive oxygen and nutrients as well as to remove wastes, leading to a significant reduction in their survival rate. Despite the advancements in bioinks and bioprinting technologies, bioprinted vascular structures continue to be unsuitable for transplantation compared to natural blood vessels. In addition, a complete assessment index system for evaluating the structure and function of bioprinted vessels in vitro has not yet been established. Therefore, in this review, we firstly highlight the significance of selecting suitable bioinks and bioprinting techniques as they two synergize with each other. Subsequently, focusing on both vascular-associated cells and vascular tissues, we provide a relatively thorough assessment of the functions of bioprinted vascular tissue based on the physiological functions that natural blood vessels possess. We end with a review of the applications of vascular models, such as vessel-on-a-chip, in simulating pathological processes and conducting drug screening at the organ level. We believe that the development of fully functional blood vessels will soon make great contributions to tissue engineering and regenerative medicine.

15.
Front Immunol ; 14: 1200875, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37283759

RESUMO

Immune checkpoint inhibitors (ICIs) target the negative regulatory pathway of T cells and effectively reactive the anti-tumor immune function of T cells by blocking the key pathway of the immune escape mechanism of the tumor-PD-1/PD-L1, and fundamentally changing the prospect of immunotherapy for non-small cell lung cancer patients. However, such promising immunotherapy is overshadowed by Hyperprogressive Disease, a response pattern associated with unwanted accelerated tumor growth and characterized by poor prognosis in a fraction of treated patients. This review comprehensively provides an overview of Hyperprogressive Disease in immune checkpoint inhibitor-based immunotherapy for non-small cell lung cancer including its definition, biomarkers, mechanisms, and treatment. A better understanding of the black side of immune checkpoint inhibitors therapy will provide a more profound insight into the pros and cons of immunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Pulmonares/patologia , Receptor de Morte Celular Programada 1 , Imunoterapia/efeitos adversos , Imunoterapia/métodos
16.
Macromol Biosci ; 23(6): e2200481, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36730643

RESUMO

Bone grafting, as the current gold-standard for large scaled bone damage of various causes, has faced challenges from both the source and appliance. Emerging new tissue engineering substitutes are demonstrating more options and possibilities, with their improved biocompatibility, accessibility, and customizable function. Amongst them, injectable gels (IGs) are a class of gel material displaying astonishing non-invasive properties and surgical viability. While possessing responsiveness toward specific stimuli, they change their physical form in vivo, thus serving as wonderful biomaterials and drug delivery systems. In this review, the mechanics of stimuli-responsive IGs developed during the past decade are illustrated. Two branches of crosslinked gels - co-valent and non-covalent crosslinked IGs and their composition and customization are introduced. In conclusion, the present trend in bone tissue engineering research is summarized and made an outlook for future. It is hoped that this comprehensive review can provide a proper reference for the development of new IGs.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Géis , Sistemas de Liberação de Medicamentos , Osso e Ossos , Hidrogéis/farmacologia
17.
Biomater Sci ; 11(10): 3486-3501, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-36974898

RESUMO

Bone defects are one of the toughest challenges faced by orthopedic surgeons worldwide, especially at critical sizes, which are caused by severe trauma, malignancy, or congenital disease. The ideal bone tissue-engineered scaffold for bone regeneration is the one that has good osteoconductivity, osteoinductivity, pore structure, and antibacterial properties. Metal ions have been recognized in recent years to be essential regulators of bone metabolism, and they are widely used for bone tissue engineering. In particular, zinc ions are of interest because of their ideal biocompatibility, osteogenesis-promoting properties, and antibacterial properties. Moreover, the dual role of strontium (Sr) in promoting osteogenesis and inhibiting osteolysis provides academic support for Zn-Sr co-doped scaffolds. Based on true bone ceramics (TBC), Zn-Sr-sintered scaffolds with good pore structures were prepared using immersion-calcination. The biocompatibility, cell adhesion, osteogenic properties, and antibacterial activity of Zn-Sr-sintered TBC scaffolds in bone marrow mesenchymal stem cells (BMSCs) are superior to those of control TBC scaffolds. The Zn-Sr-sintered TBC scaffold was used to repair rat cranial defects. Its good in vivo repair performance was confirmed by osseointegration and inward bone growth compared with that of the control TBC scaffold. Zn0.25Sr0.20-TBC is an ideal material for bone repair because of its good biocompatibility and favorable in vitro osteogenic properties.


Assuntos
Estrôncio , Alicerces Teciduais , Ratos , Animais , Estrôncio/farmacologia , Estrôncio/química , Alicerces Teciduais/química , Osteogênese , Engenharia Tecidual , Regeneração Óssea , Cerâmica/farmacologia , Cerâmica/química , Zinco/química
18.
Adv Healthc Mater ; 12(29): e2301604, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37584445

RESUMO

Previous parathyroid hormone (PTH)-related peptides (PTHrPs) cannot be used to prevent implant loosening in osteoporosis patients due to the catabolic effect of local sustained release. A novel PTHrP (PTHrP-2) that can be used locally to promote osseointegration of macroporous titanium alloy scaffold (mTAS) and counteract implant slippage in osteoporosis patients is designed. In vitro, PTHrP-2 enhances the proliferation, adhesion, and osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) within the mTAS. Further, it promotes proliferation, migration, angiogenesis-related protein expression, and angiogenesis in human umbilical vein endothelial cells (HUVECs). Compared to PTH(1-34), PTHrP-2 can partially weaken the osteoclast differentiation of RAW 264.7 cells. Even in an oxidative stress microenvironment, PTHrP-2 safeguards the proliferation and migration of BMSCs and HUVECs, reduces reactive oxygen species generation and mitochondrial damage, and partially preserves the angiogenesis of HUVECs. In the Sprague-Dawley (SD) rat osteoporosis model, the therapeutic benefits of PTHrP-2-releasing mTAS (mTASP2 ) and ordinary mTAS implanted for 12 weeks via micro-CT, sequential fluorescent labeling, and histology are compared. The results demonstrate that mTASP2 exhibits high bone growth rate, without osteophyte formation. Consequently, PTHrP-2 exhibits unique local synthesis properties and holds the potential for assisting the osseointegration of alloy implants in osteoporosis patients.


Assuntos
Osseointegração , Osteoporose , Ratos , Animais , Humanos , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Titânio/química , Ratos Sprague-Dawley , Osteogênese , Ligas/farmacologia , Células Endoteliais , Osteoporose/tratamento farmacológico , Impressão Tridimensional
19.
Macromol Rapid Commun ; 33(10): 933-7, 2012 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-22368120

RESUMO

A straightforward strategy for assembling polymeric dimers from amphiphilic nanoparticles is reported. Amphiphilic polymeric nanoparticles with a mixed-shell of PEO/P2VN blocks and a flexible core of PAA blocks are fabricated by a non-covalent crosslinking method. Uniform polymeric dimers are efficiently and simply obtained via hydrophobic interactions under optimized conditions in selective solvent. The steric hindrance generated by reorganization of hydrophilic polymer brushes during the interparticle association is critical for morphological selectivity in the assembly. General applicability offers the possibility to organize functional NPs into superstructures with well-defined geometry and association numbers.


Assuntos
Polímeros/química , Resinas Acrílicas/química , Interações Hidrofóbicas e Hidrofílicas , Micelas , Nanopartículas/química , Polietilenoglicóis/química , Polivinil/química , Solventes/química
20.
Sci Rep ; 12(1): 2191, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35140298

RESUMO

Recently, plant essential oils (EOs) have attracted special attention in plant disease control and food preservation. Since ancient times, essential oils extracted from plants have exhibited many biological characteristics, especially antimicrobial properties. Recent studies have described the potentials of EOs and derivatives to inhibit the growth and reproduction of microorganisms, mainly in response of overwhelming concerns of consumers about food safety. In the context of returning to nature, with the advancement of science and technology and improved living standards, people have begun to seek solutions for food hygiene without chemical additives. Therefore, biological pesticides and plant-oriented chemicals have received special attention from scientists because they are environmentally friendly and nonhazardous, sustainable, and effective alternatives against many noxious phytopathogens. Present study is intended to appraise the fungicidal properties of ginger EOs to combat leaf blight disease of taro, which threatens global taro production. Farmers often hinge on extremely toxic synthetic fungicides to manage diseases, but the residual effects and resistance of chemicals are unavoidable. The microwave-assisted hydrodistillation method was used for ginger EOs extraction and an FTIR (ATR) spectrometer was used to evaluate their chemical composition and citral was identified as most abundant compound (89.05%) in oil. The pathogen isolated from lesions of diseased taro plants was identified as Phytophthora colocasiae and used as test fungus in the present study. Ginger EO was evaluated in-vitro for antifungal properties against mycelium growth, sporangium production, zoospore germination, leaf, and corm necrosis inhibition. Repeated experiments have shown that the concentration of ginger essential oil (1250 ppm) proved to be the lowest dose to obtain 100% inhibition of fungal growth and spore germination, sporangia formation and leaf necrosis assessment. These results are derived from this fungal species and a hypothesis that involves further research on other plant pathogens to demonstrate the overall potency of essential oils. This study references the easy, economic, and environmental management and control of plant diseases using essential oils and byproducts.


Assuntos
Antifúngicos/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Phytophthora/efeitos dos fármacos , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Zingiber officinale/química , Colocasia/efeitos dos fármacos , Colocasia/parasitologia , Fungos/efeitos dos fármacos , Germinação/efeitos dos fármacos , Micélio/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/microbiologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Esporângios/efeitos dos fármacos , Esporos/efeitos dos fármacos
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