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1.
Proc Natl Acad Sci U S A ; 121(28): e2404210121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38954541

RESUMO

Mesenchymal stem cells (MSCs) are essential in regenerative medicine. However, conventional expansion and harvesting methods often fail to maintain the essential extracellular matrix (ECM) components, which are crucial for their functionality and efficacy in therapeutic applications. Here, we introduce a bone marrow-inspired macroporous hydrogel designed for the large-scale production of MSC-ECM spheroids. Through a soft-templating approach leveraging liquid-liquid phase separation, we engineer macroporous hydrogels with customizable features, including pore size, stiffness, bioactive ligand distribution, and enzyme-responsive degradability. These tailored environments are conducive to optimal MSC proliferation and ease of harvesting. We find that soft hydrogels enhance mechanotransduction in MSCs, establishing a standard for hydrogel-based 3D cell culture. Within these hydrogels, MSCs exist as both cohesive spheroids, preserving their innate vitality, and as migrating entities that actively secrete functional ECM proteins. Additionally, we also introduce a gentle, enzymatic harvesting method that breaks down the hydrogels, allowing MSCs and secreted ECM to naturally form MSC-ECM spheroids. These spheroids display heightened stemness and differentiation capacity, mirroring the benefits of a native ECM milieu. Our research underscores the significance of sophisticated materials design in nurturing distinct MSC subpopulations, facilitating the generation of MSC-ECM spheroids with enhanced therapeutic potential.


Assuntos
Matriz Extracelular , Hidrogéis , Células-Tronco Mesenquimais , Esferoides Celulares , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Hidrogéis/química , Matriz Extracelular/metabolismo , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Humanos , Diferenciação Celular , Técnicas de Cultura de Células/métodos , Proliferação de Células , Porosidade , Mecanotransdução Celular/fisiologia , Células Cultivadas
2.
J Nanobiotechnology ; 22(1): 387, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951841

RESUMO

Metal-organic frameworks (MOFs) are metal-organic skeleton compounds composed of self-assembled metal ions or clusters and organic ligands. MOF materials often have porous structures, high specific surface areas, uniform and adjustable pores, high surface activity and easy modification and have a wide range of prospects for application. MOFs have been widely used. In recent years, with the continuous expansion of MOF materials, they have also achieved remarkable results in the field of antimicrobial agents. In this review, the structural composition and synthetic modification of MOF materials are introduced in detail, and the antimicrobial mechanisms and applications of these materials in the healing of infected wounds are described. Moreover, the opportunities and challenges encountered in the development of MOF materials are presented, and we expect that additional MOF materials with high biosafety and efficient antimicrobial capacity will be developed in the future.


Assuntos
Estruturas Metalorgânicas , Cicatrização , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Cicatrização/efeitos dos fármacos , Humanos , Animais , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/química , Porosidade , Infecção dos Ferimentos/tratamento farmacológico
3.
Nat Commun ; 15(1): 5518, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951539

RESUMO

Determining short-lived intermediate structures in chemical reactions is challenging. Although ultrafast spectroscopic methods can detect the formation of transient intermediates, real-space structures cannot be determined directly from such studies. Time-resolved serial femtosecond crystallography (TR-SFX) has recently proven to be a powerful method for capturing molecular changes in proteins on femtosecond timescales. However, the methodology has been mostly applied to natural proteins/enzymes and limited to reactions promoted by synthetic molecules due to structure determination challenges. This work demonstrates the applicability of TR-SFX for investigations of chemical reaction mechanisms of synthetic metal complexes. We fix a light-induced CO-releasing Mn(CO)3 reaction center in porous hen egg white lysozyme (HEWL) microcrystals. By controlling light exposure and time, we capture the real-time formation of Mn-carbonyl intermediates during the CO release reaction. The asymmetric protein environment is found to influence the order of CO release. The experimentally-observed reaction path agrees with quantum mechanical calculations. Therefore, our demonstration offers a new approach to visualize atomic-level reactions of small molecules using TR-SFX with real-space structure determination. This advance holds the potential to facilitate design of artificial metalloenzymes with precise mechanisms, empowering design, control and development of innovative reactions.


Assuntos
Manganês , Muramidase , Muramidase/química , Manganês/química , Cristalografia por Raios X , Porosidade , Complexos de Coordenação/química , Modelos Moleculares , Animais , Monóxido de Carbono/química , Fatores de Tempo , Galinhas
4.
BMC Musculoskelet Disord ; 25(1): 510, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961446

RESUMO

PURPOSE: Crowe IV developmental dysplasia of the hip (DDH) is a catastrophic hip disease. Moreover, obtaining ideal clinical efficacy in conventional total hip arthroplasty (THA) is often difficult. In this study, we aimed to assess the mid-term clinical results of THA with porous tantalum trabecular metal (TM) pads for acetabular reconstruction in the treatment of Crowe IV DDH. METHODS: A cohort of 28 patients (32 hips) diagnosed with Crowe type IV DDH who underwent acetabular reconstruction during THA using TM pads with scheduled follow-up between 2011 and 2018, were included in this study. Eight cases were men and 24 were women, with a mean age of 48.4 years (range, 36-72 years) and a mean follow-up was 74.3 months (range, 42-132 months). All patients underwent acetabular reconstruction using TM pads and total hip replacement with subtrochanteric osteotomy. RESULTS: At the final follow-up, 28 hips (87.5%) demonstrated mild or no postoperative limping. The Harris Hip Score improved from 58.4 ± 10.6 preoperatively to 85.6 ± 8.9. The mean pain, stiffness, and function scores on the Western Ontario and McMaster University Osteoarthritis index were 86.5 ± 10.2, 87.3 ± 12.4 and 85.4 ± 11.6 respectively. The mean score of patient satisfaction was 90.4 ± 7.6. Additionally, the SF-12 physical summary score was 41.8 ± 5.6 and the SF-12 mental summary score was 51.6 ± 5.4. TM construct survivorship due to all-cause failure was 90.6% at 5 years with 3 hips at risk, 87.5% at 10 years with 4 hips at risk. The survivorship due to failure from aseptic loosening was 96.9% at 5 years with 1hips at risk and 93.75% at 10 years with 2 hips at risk. CONCLUSION: This study demonstrated satisfactory mid-term clinical and radiological results with the application of TM pads for acetabular reconstruction combined with THA in patients with Crowe IV DDH. TRIAL REGISTRATION NUMBER: ChiCTR1800014526, Date: 18/01/2018.


Assuntos
Artroplastia de Quadril , Displasia do Desenvolvimento do Quadril , Prótese de Quadril , Tantálio , Humanos , Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Pessoa de Meia-Idade , Feminino , Masculino , Idoso , Adulto , Seguimentos , Displasia do Desenvolvimento do Quadril/cirurgia , Displasia do Desenvolvimento do Quadril/diagnóstico por imagem , Resultado do Tratamento , Acetábulo/cirurgia , Acetábulo/diagnóstico por imagem , Desenho de Prótese , Estudos Retrospectivos , Porosidade
5.
Anal Chim Acta ; 1316: 342879, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38969416

RESUMO

BACKGROUND: Chirality is a ubiquitous phenomenon in nature, but enantiomers exhibit different pharmacological activities and toxicological effects. Therefore, Chiral recognition plays a pivotal role in various fields such as life sciences, chemical synthesis, drug development, and materials science. The synthesis of novel chiral composites with well-defined loading capabilities and ordered structures holds significant potential for electrochemical chiral recognition applications. However, the design of selective and stable electrochemical chiral recognition materials remains a challenging task. RESULT: In this work, we construct a simple and rapid electrochemical sensing platform for tryptophan (Trp) enantiomer recognition using cyclodextrin-modified microporous organic network as chiral recognition agent. CD-MON with chiral microenvironment was prepared by Sonogashira-Hagihara coupling reaction of the chiral molecule heptyl-6-iodo-6-deoxyß-cyclodextrin and 1, 4-Diethynylbenzene. The adhesion of BSA makes CD-MON firmly fixed on the electrode surface, and as a chiral protein, it can improve the chiral recognition ability through synergistic effect. Chiral amino acids are in full contact with the chiral microenvironment during pore conduction of MON, and L-Trp is more stably bound to CD-MON/BSA due to steric hindrance, host-guest recognition and hydrogen bonding. Therefore, the electrochemical sensor can effectively identify tryptophan enantiomers (IL-Trp/ID-Trp = 2.02), and it exhibits a detection limit of 2.6 µM for L-Trp. UV-Vis spectroscopy confirmed the adsorption capacity of CD-MON towards tryptophan enantiomers in agreement with electrochemistry results. SIGNIFICANCE: The prepared chiral sensor has excellent stability, reproducibility (RSD = 3.7%) and selectivity, realizes the quantitative detection of single isomer in tryptophan racemic and quantitative analysis in real samples with 94.0%-101.0% recovery. This work represents the first application of MON in chiral electrochemistry which expands the application scope of chiral sensors and holds great significance in separation science and electrochemical sensing.


Assuntos
Ciclodextrinas , Técnicas Eletroquímicas , Estereoisomerismo , Técnicas Eletroquímicas/métodos , Ciclodextrinas/química , Porosidade , Triptofano/análise , Triptofano/química , Aminoácidos/análise , Aminoácidos/química , Limite de Detecção , Animais , Eletrodos , Soroalbumina Bovina/química
6.
Mikrochim Acta ; 191(7): 438, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951285

RESUMO

A dual-recognition strategy is reported to construct a one-step washing and highly efficient signal-transduction tag system for high-sensitivity colorimetric detection of Staphylococcus aureus (S. aureus). The porous (gold core)@(platinum shell) nanozymes (Au@PtNEs) as the signal labels show highly efficient peroxidase mimetic activity and are robust. For the sake of simplicity the detection involved the use of a vancomycin-immobilized magnetic bead (MB) and aptamer-functionalized Au@PtNEs for dual-recognition detection in the presence of S. aureus. In addition, we designed a magnetic plate to fit the 96-well microplate to ensure consistent magnetic properties of each well, which can quickly remove unreacted Au@PtNEs and sample matrix while avoiding tedious washing steps. Subsequently, Au@PtNEs catalyze hydrogen peroxide (H2O2) to oxidize 3,3',5,5'-tetramethylbenzidine (TMB) generating a color signal. Finally, the developed Au@PtNEs-based dual-recognition washing-free colorimetric assay displayed a response in the range of S. aureus of 5 × 101-5 × 105 CFU/mL, and the detection limit was 40 CFU/mL within 1.5 h. In addition, S. aureus-fortified samples were analyzed to further evaluate the performance of the proposed method, which yielded average recoveries ranging from 93.66 to 112.44% and coefficients of variation (CVs) within the range 2.72-9.01%. These results furnish a novel horizon for the exploitation of a different mode of recognition and inexpensive enzyme-free assay platforms as an alternative to traditional enzyme-based immunoassays for the detection of other Gram-positive pathogenic bacteria.


Assuntos
Benzidinas , Colorimetria , Ouro , Peróxido de Hidrogênio , Limite de Detecção , Platina , Staphylococcus aureus , Staphylococcus aureus/isolamento & purificação , Colorimetria/métodos , Ouro/química , Platina/química , Porosidade , Benzidinas/química , Peróxido de Hidrogênio/química , Aptâmeros de Nucleotídeos/química , Nanopartículas Metálicas/química , Vancomicina/química , Técnicas Biossensoriais/métodos , Catálise , Humanos
7.
J Mater Sci Mater Med ; 35(1): 38, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958834

RESUMO

Fabrication of porous tissue-engineering scaffolds from bioactive glasses (BAG) is complicated by the tendency of BAG compositions to crystallize in thermal treatments during scaffold manufacture. Here, experimental biocompatible glass S59 (SiO2 59.7 wt%, Na2O 25.5 wt%, CaO 11.0 wt%, P2O5 2.5 wt%, B2O3 1.3 wt%), known to be resistant to crystallization, was used in sintering of glass granules (300-500 µm) into porous scaffolds. The dissolution behavior of the scaffolds was then studied in vivo in rabbit femurs and under continuous flow conditions in vitro (14 days in vitro/56 days in vivo). The scaffolds were osteoconductive in vivo, as bone could grow into the scaffold structure. Still, the scaffolds could not induce sufficiently rapid bone ingrowth to replace the strength lost due to dissolution. The scaffolds lost their structure and strength as the scaffold necks dissolved. In vitro, S59 dissolved congruently throughout the 14-day experiments, resulting in only a slight reaction layer formation. Manufacturing BAG scaffolds from S59 that retain their amorphous structure was thus possible. The relatively rapid and stable dissolution of the scaffold implies that the glass S59 may have the potential to be used in composite implants providing initial strength and stable, predictable release of ions over longer exposure times.


Assuntos
Materiais Biocompatíveis , Vidro , Teste de Materiais , Engenharia Tecidual , Alicerces Teciduais , Animais , Coelhos , Alicerces Teciduais/química , Vidro/química , Materiais Biocompatíveis/química , Porosidade , Engenharia Tecidual/métodos , Fêmur , Solubilidade , Substitutos Ósseos/química , Regeneração Óssea
8.
Sci Rep ; 14(1): 15339, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961115

RESUMO

Given the hierarchical nature of bone and bone interfaces, osseointegration, namely the formation of a direct bone-implant contact, is best evaluated using a multiscale approach. However, a trade-off exists between field of view and spatial resolution, making it challenging to image large volumes with high resolution. In this study, we combine established electron microscopy techniques to probe bone-implant interfaces at the microscale and nanoscale with plasma focused ion beam-scanning electron microscopy (PFIB-SEM) tomography to evaluate osseointegration at the mesoscale. This characterization workflow is demonstrated for bone response to an additively manufactured Ti-6Al-4V implant which combines engineered porosity to facilitate bone ingrowth and surface functionalization via genistein, a phytoestrogen, to counteract bone loss in osteoporosis. SEM demonstrated new bone formation at the implant site, including in the internal implant pores. At the nanoscale, scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy confirmed the gradual nature of the bone-implant interface. By leveraging mesoscale analysis with PFIB-SEM tomography that captures large volumes of bone-implant interface with nearly nanoscale resolution, the presence of mineral ellipsoids varying in size and orientation was revealed. In addition, a well-developed lacuno-canalicular network and mineralization fronts directed both towards the implant and away from it were highlighted.


Assuntos
Genisteína , Osseointegração , Titânio , Osseointegração/efeitos dos fármacos , Genisteína/farmacologia , Genisteína/química , Titânio/química , Animais , Materiais Revestidos Biocompatíveis/química , Interface Osso-Implante , Microscopia Eletrônica de Varredura , Próteses e Implantes , Porosidade , Ligas/química
9.
Int J Nanomedicine ; 19: 6337-6358, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38946884

RESUMO

Background: It is well-established that osteoclast activity is significantly influenced by fluctuations in intracellular pH. Consequently, a pH-sensitive gated nano-drug delivery system represents a promising therapeutic approach to mitigate osteoclast overactivity. Our prior research indicated that naringin, a natural flavonoid, effectively mitigates osteoclast activity. However, naringin showed low oral availability and short half-life, which hinders its clinical application. We developed a drug delivery system wherein chitosan, as gatekeepers, coats mesoporous silica nanoparticles loaded with naringin (CS@MSNs-Naringin). However, the inhibitory effects of CS@MSNs-Naringin on osteoclasts and the underlying mechanisms remain unclear, warranting further research. Methods: First, we synthesized CS@MSNs-Naringin and conducted a comprehensive characterization. We also measured drug release rates in a pH gradient solution and verified its biosafety. Subsequently, we investigated the impact of CS@MSNs-Naringin on osteoclasts induced by bone marrow-derived macrophages, focusing on differentiation and bone resorption activity while exploring potential mechanisms. Finally, we established a rat model of bilateral critical-sized calvarial bone defects, in which CS@MSNs-Naringin was dispersed in GelMA hydrogel to achieve in situ drug delivery. We observed the ability of CS@MSNs-Naringin to promote bone regeneration and inhibit osteoclast activity in vivo. Results: CS@MSNs-Naringin exhibited high uniformity and dispersity, low cytotoxicity (concentration≤120 µg/mL), and significant pH sensitivity. In vitro, compared to Naringin and MSNs-Naringin, CS@MSNs-Naringin more effectively inhibited the formation and bone resorption activity of osteoclasts. This effect was accompanied by decreased phosphorylation of key factors in the NF-κB and MAPK signaling pathways, increased apoptosis levels, and a subsequent reduction in the production of osteoclast-specific genes and proteins. In vivo, CS@MSNs-Naringin outperformed Naringin and MSNs-Naringin, promoting new bone formation while inhibiting osteoclast activity to a greater extent. Conclusion: Our research suggested that CS@MSNs-Naringin exhibited the strikingly ability to anti-osteoclasts in vitro and in vivo, moreover promoted bone regeneration in the calvarial bone defect.


Assuntos
Regeneração Óssea , Flavanonas , Nanopartículas , Osteoclastos , Dióxido de Silício , Flavanonas/química , Flavanonas/farmacologia , Flavanonas/farmacocinética , Flavanonas/administração & dosagem , Animais , Osteoclastos/efeitos dos fármacos , Regeneração Óssea/efeitos dos fármacos , Dióxido de Silício/química , Concentração de Íons de Hidrogênio , Nanopartículas/química , Ratos , Camundongos , Ratos Sprague-Dawley , Quitosana/química , Masculino , Liberação Controlada de Fármacos , Porosidade , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Reabsorção Óssea/tratamento farmacológico , Células RAW 264.7 , Sistemas de Liberação de Medicamentos/métodos , Diferenciação Celular/efeitos dos fármacos
10.
Int J Nanomedicine ; 19: 6449-6462, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38946883

RESUMO

Purpose: Functional inorganic nanomaterials (NMs) are widely exploited as bioactive materials and drug depots. The lack of a stable form of application of NMs at the site of skin injury, may impede the removal of the debridement, elevate pH, induce tissue toxicity, and limit their use in skin repair. This necessitates the advent of innovative wound dressings that overcome the above limitations. The overarching objective of this study was to exploit strontium-doped mesoporous silicon particles (PSiSr) to impart multifunctionality to poly(lactic-co-glycolic acid)/gelatin (PG)-based fibrous dressings (PG@PSiSr) for excisional wound management. Methods: Mesoporous silicon particles (PSi) and PSiSr were synthesized using a chemo-synthetic approach. Both PSi and PSiSr were incorporated into PG fibers using electrospinning. A series of structure, morphology, pore size distribution, and cumulative pH studies on the PG@PSi and PG@PSiSr membranes were performed. Cytocompatibility, hemocompatibility, transwell migration, scratch wound healing, and delineated angiogenic properties of these composite dressings were tested in vitro. The biocompatibility of composite dressings in vivo was assessed by a subcutaneous implantation model of rats, while their potential for wound healing was discerned by implantation in a full-thickness excisional defect model of rats. Results: The PG@PSiSr membranes can afford the sustained release of silicon ions (Si4+) and strontium ions (Sr2+) for up to 192 h as well as remarkably promote human umbilical vein endothelial cells (HUVECs) and NIH-3T3 fibroblasts migration. The PG@PSiSr membranes also showed better cytocompatibility, hemocompatibility, and significant formation of tubule-like networks of HUVECs in vitro. Moreover, PG@PSiSr membranes also facilitated the infiltration of host cells and promoted the deposition of collagen while reducing the accumulation of inflammatory cells in a subcutaneous implantation model in rats as assessed for up to day 14. Further evaluation of membranes transplanted in a full-thickness excisional wound model in rats showed rapid wound closure (PG@SiSr vs control, 96.1% vs 71.7%), re-epithelialization, and less inflammatory response alongside skin appendages formation (eg, blood vessels, glands, hair follicles, etc.). Conclusion: To sum up, we successfully fabricated PSiSr particles and prepared PG@PSiSr dressings using electrospinning. The PSiSr-mediated release of therapeutic ions, such as Si4+ and Sr2+, may improve the functionality of PLGA/Gel dressings for an effective wound repair, which may also have implications for the other soft tissue repair disciplines.


Assuntos
Bandagens , Gelatina , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Silício , Pele , Estrôncio , Cicatrização , Gelatina/química , Animais , Estrôncio/química , Estrôncio/farmacologia , Cicatrização/efeitos dos fármacos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Pele/efeitos dos fármacos , Porosidade , Ratos , Humanos , Silício/química , Ratos Sprague-Dawley , Camundongos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Masculino , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
11.
Methods Enzymol ; 700: 455-483, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38971610

RESUMO

Over the years, it has become more and more obvious that lipid membranes show a very complex behavior. This behavior arises in part from the large number of different kinds of lipids and proteins and how they dynamically interact with each other. In vitro studies using artificial membrane systems have shed light on the heterogeneity based on lipid-lipid interactions in multicomponent bilayer mixtures. Inspired by the raft hypothesis, the coexistence of liquid-disordered (ld) and liquid-ordered (lo) phases has drawn much attention. It was shown that ternary lipid mixtures containing low- and high-melting temperature lipids and cholesterol can phase separate into a lo phase enriched in the high-melting lipids and cholesterol and a ld phase enriched in the low-melting lipids. Depending on the model membrane system under investigation, different domain sizes, shapes, and mobilities have been found. Here, we describe how to generate phase-separated lo/ld phases in model membrane systems termed pore-spanning membranes (PSMs). These PSMs are prepared on porous silicon substrates with pore sizes in the micrometer regime. A proper functionalization of the top surface of the substrates is required to achieve the spreading of giant unilamellar vesicles (GUVs) to obtain PSMs. Starting with lo/ld phase-separated GUVs lead to membrane heterogeneities in the PSMs. Depending on the functionalization strategy of the top surface of the silicon substrate, different membrane heterogeneities are observed in the PSMs employing fluorescence microscopy. A quantitative analysis of the heterogeneity as well as the dynamics of the lipid domains is described.


Assuntos
Bicamadas Lipídicas , Bicamadas Lipídicas/química , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Porosidade , Microdomínios da Membrana/química , Microdomínios da Membrana/metabolismo , Colesterol/química
12.
Nat Commun ; 15(1): 5460, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937462

RESUMO

Developing superporous hemostatic sponges with simultaneously enhanced permeability and mechanical properties remains challenging but highly desirable to achieve rapid hemostasis for non-compressible hemorrhage. Typical approaches to improve the permeability of hemostatic sponges by increasing porosity sacrifice mechanical properties and yield limited pore interconnectivity, thereby undermining the hemostatic efficacy and subsequent tissue regeneration. Herein, we propose a temperature-assisted secondary network compaction strategy following the phase separation-induced primary compaction to fabricate the superporous chitosan sponge with highly-interconnected porous structure, enhanced blood absorption rate and capacity, and fatigue resistance. The superporous chitosan sponge exhibits rapid shape recovery after absorbing blood and maintains sufficient pressure on wounds to build a robust physical barrier to greatly improve hemostatic efficiency. Furthermore, the superporous chitosan sponge outperforms commercial gauze, gelatin sponges, and chitosan powder by enhancing hemostatic efficiency, cell infiltration, vascular regeneration, and in-situ tissue regeneration in non-compressible organ injury models, respectively. We believe the proposed secondary network compaction strategy provides a simple yet effective method to fabricate superporous hemostatic sponges for diverse clinical applications.


Assuntos
Quitosana , Hemostasia , Hemostáticos , Permeabilidade , Animais , Porosidade , Quitosana/química , Hemostáticos/química , Hemostáticos/farmacologia , Suínos , Hemostasia/fisiologia , Hemorragia/terapia , Masculino
13.
Inorg Chem ; 63(26): 12377-12384, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38902911

RESUMO

Pathogenic bacteria have consistently posed a formidable challenge to human health, creating the critical need for effective antibacterial solutions. In response, enzyme-metal-organic framework (MOF) composites have emerged as a promising class of antibacterial agents. This study focuses on the development of an enzyme-MOF composite based on HZIF-8, incorporating the advantages of simple synthesis, ZIF-8 antibacterial properties, lysozyme hydrolysis, and high biological safety. Through a one-pot method, core-shell nanoparticles (HZIF-8) were synthesized. This structure enables efficient immobilization of lysozyme and lactoferrin within the HZIF-8, resulting in the formation of the lysozyme-lactoferrin@HZIF-8 (LYZ-LF@HZIF-8) composite. Upon exposure to light irradiation, HZIF-8 itself possessed antibacterial properties. Lysozyme initiated the degradation of bacterial peptidoglycan and lactoferrin synergistically enhanced the antibacterial effect of lysozyme. All of the above ultimately contributed to comprehensive antibacterial activity. Antibacterial assessments demonstrated the efficacy of the LYZ-LF@HZIF-8 composite, effectively eradicating Staphylococcus aureus at a cell density of 1.5 × 106 CFU/mL with a low dosage of 200 µg/mL and completely inactivating Escherichia coli at 400 µg/mL with the same cell density. The enzyme-MOF composite exhibited significant and durable antibacterial efficacy, with no apparent cytotoxicity in vitro, thereby unveiling expansive prospects for applications in the medical and food industries.


Assuntos
Antibacterianos , Escherichia coli , Lactoferrina , Estruturas Metalorgânicas , Testes de Sensibilidade Microbiana , Muramidase , Staphylococcus aureus , Zeolitas , Muramidase/farmacologia , Muramidase/química , Muramidase/metabolismo , Lactoferrina/química , Lactoferrina/farmacologia , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Zeolitas/química , Zeolitas/farmacologia , Imidazóis/química , Imidazóis/farmacologia , Imidazóis/síntese química , Porosidade , Propriedades de Superfície , Tamanho da Partícula , Enzimas Imobilizadas/química , Enzimas Imobilizadas/farmacologia
14.
Int J Mol Sci ; 25(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38928145

RESUMO

Polyurethane (PU) is a promising material for addressing challenges in bone grafting. This study was designed to enhance the bone grafting capabilities of PU by integrating hydroxyapatite (HAp), which is known for its osteoconductive and osteoinductive potential. Moreover, a uniform distribution of HAp in the porous structure of PU increased the effectiveness of bone grafts. PEG/APTES-modified scaffolds were prepared through self-foaming reactions. A uniform pore structure was generated during the spontaneous foaming reaction, and HAp was uniformly distributed in the PU structure (PU15HAp and PU30HAp) during foaming. Compared with the PU scaffolds, the HAp-modified PU scaffolds exhibited significantly greater protein absorption. Importantly, the effect of the HAp-modified PU scaffold on bone repair was tested in a rat calvarial defect model. The microstructure of the newly formed bone was analyzed with microcomputed tomography (µ-CT). Bone regeneration at the defect site was significantly greater in the HAp-modified PU scaffold group than in the PU group. This innovative HAp-modified PU scaffold improves current bone graft materials, providing a promising avenue for improved bone regeneration.


Assuntos
Regeneração Óssea , Durapatita , Poliuretanos , Crânio , Alicerces Teciduais , Poliuretanos/química , Animais , Durapatita/química , Alicerces Teciduais/química , Ratos , Regeneração Óssea/efeitos dos fármacos , Crânio/efeitos dos fármacos , Crânio/lesões , Crânio/patologia , Crânio/metabolismo , Ratos Sprague-Dawley , Microtomografia por Raio-X , Masculino , Porosidade , Transplante Ósseo/métodos
15.
Int J Mol Sci ; 25(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38928184

RESUMO

Simple and efficient sample pretreatment methods are important for analysis and detection of chemical warfare agents (CWAs) in environmental and biological samples. Despite many commercial materials or reagents that have been already applied in sample preparation, such as SPE columns, few materials with specificity have been utilized for purification or enrichment. In this study, ionic magnetic mesoporous nanomaterials such as poly(4-VB)@M-MSNs (magnetic mesoporous silicon nanoparticles modified by 4-vinyl benzene sulfonic acid) and Co2+@M-MSNs (magnetic mesoporous silicon nanoparticles modified by cobalt ions) with high absorptivity for ethanol amines (EAs, nitrogen mustard degradation products) and cyanide were successfully synthesized. The special nanomaterials were obtained by modification of magnetic mesoporous particles prepared based on co-precipitation using -SO3H and Co2+. The materials were fully characterized in terms of their composition and structure. The results indicated that poly(4-VB)@M-MSNs or Co2+@M-MSNs had an unambiguous core-shell structure with a BET of 341.7 m2·g-1 and a saturation magnetization intensity of 60.66 emu·g-1 which indicated the good thermal stability. Poly(4-VB)@M-MSNs showed selective adsorption for EAs while the Co2+@M-MSNs were for cyanide, respectively. The adsorption capacity quickly reached the adsorption equilibrium within the 90 s. The saturated adsorption amounts were MDEA = 35.83 mg·g-1, EDEA = 35.00 mg·g-1, TEA = 17.90 mg·g-1 and CN-= 31.48 mg·g-1, respectively. Meanwhile, the adsorption capacities could be maintained at 50-70% after three adsorption-desorption cycles. The adsorption isotherms were confirmed as the Langmuir equation and the Freundlich equation, respectively, and the adsorption mechanism was determined by DFT calculation. The adsorbents were applied for enrichment of targets in actual samples, which showed great potential for the verification of chemical weapons and the destruction of toxic chemicals.


Assuntos
Aminas , Cianetos , Etanol , Cianetos/química , Cianetos/isolamento & purificação , Adsorção , Aminas/química , Etanol/química , Porosidade , Cobalto/química , Nanopartículas de Magnetita/química , Nanoestruturas/química
16.
Iowa Orthop J ; 44(1): 63-68, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919359

RESUMO

Background: The specific aim of this study was to evaluate the mechanical properties of cement prepared with the advanced one-step mixing system and whether the addition of vacuum conditions yielded an appreciable improvement in the biomechanical strength or overall quality of bone cement. Methods: The advanced one-step mixing system was used. Twelve specimens were prepared by mixing under vacuum conditions and 12 specimens were prepared by mixing without a vacuum. Radiographs of cement specimens were analyzed to determine the porosity of the test region. Tensile testing of the specimens was performed with a loading rate of 2.54mm/min at room temperature. The ultimate tensile strength (UTS) and the tensile elastic modulus (E) were determined for each sample. Results: The UTS of the bone cement samples mixed under vacuum conditions were not significantly different than those mixed without vacuum (vacuum: 39±6MPa; non-vacuum: 35±6MPa; p=0.637). The E of samples mixed under vacuum conditions was significantly higher than the bone cement mixed without vacuum (vacuum: 2.78±0.06GPa; non-vacuum: 2.63±0.15GPa; p=0.019). Radiographic images showed samples mixed under vacuum conditions contained fewer defects than the samples mixed without vacuum (vacuum: 3.5%±3.3% (range: 0.0%-9.0%); non-vacuum: 6.9%±1.0% (range: 4.6%-8.2%)). Conclusion: Mixing bone cement with the advanced one-step mixing system under vacuum conditions does not produce an appreciable difference in the UTS of the bone cement in a bench biomechanical testing model compared to the bone cement mixed without vacuum. It does, however, create a less porous cement mixture with a higher E compared to cement mixed without vacuum. Level of Evidence: V.


Assuntos
Cimentos Ósseos , Teste de Materiais , Resistência à Tração , Vácuo , Polimetil Metacrilato/química , Humanos , Módulo de Elasticidade , Fenômenos Biomecânicos , Porosidade
17.
Anal Methods ; 16(25): 4104-4115, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38855940

RESUMO

Fluoroquinolone (FQ) antibiotics, one of the leading environmental pollutants, have ecotoxic effects that can accumulate through ecosystems and harm human health. The determination of FQs is still difficult due to the complex matrix, many interfering factors, and low concentration. Hence, a magnetic microporous organic network (MON) composite denoted as Fe3O4@MON-NH2@CM-ß-CD with excellent FQ adsorption performance was prepared by ß-CD covalent modification of a MON. Based on the existence of π-π packing, hydrophobic interaction, and hydrogen bonding between Fe3O4@MON-NH2@CM-ß-CD and FQs, a new magnetic solid phase extraction (MSPE) method for the enrichment of FQs was developed. Under optimized MSPE conditions, five FQs were detected by HPLC-UV with good linearity (R2 ≥ 0.9989) in the range of 0.02-1 µg mL-1, and detection limits (S/N = 3) in the range of 0.0014-0.0023 µg mL-1. The satisfactory recoveries ranged from 93.1 to 116.2% with RSDs lower than 8.39% when applied to actual environmental water samples. These results revealed that Fe3O4@MON-NH2@CM-ß-CD as an adsorbent for MSPE had excellent performance for FQ extraction from real samples, and the MON material types were expanded through the functionalization of MONs, which would have great potential for further application in various analytical methods.


Assuntos
Antibacterianos , Fluoroquinolonas , Extração em Fase Sólida , Poluentes Químicos da Água , beta-Ciclodextrinas , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Fluoroquinolonas/análise , Fluoroquinolonas/química , Fluoroquinolonas/isolamento & purificação , Extração em Fase Sólida/métodos , Antibacterianos/análise , Antibacterianos/química , beta-Ciclodextrinas/química , Porosidade , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção
18.
Chemosphere ; 361: 142533, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38849099

RESUMO

Development of effective adsorbents for the removal of contaminants from wastewater is indispensable due to increasing water scarcity and a lack of pure drinking water, which are prevailing as a result of rapid industrialization and population growth. Recently, the development of new adsorbents and their effective use without generating secondary waste is receiving huge consideration. In order to protect the environment from primary and secondary pollution, the development of adsorbents from wastes and their recycling have become conventional practices aimed at waste management. As a result, significant progress has been made in the synthesis of new porous carbon and metal-organic frameworks as adsorbents, with the objective of using them for the removal of pollutants. While many different kinds of pollutants are produced in the environment, drug pollutants are the most vicious because of their tendency to undergo significant structural changes, producing metabolites and residues with entirely different properties compared to their parent compounds. Chemical reactions involving oxidation, hydrolysis, and photolysis transform drugs. The resulting compounds can have detrimental effects on living beings that are present in soil and water. This review stresses the development of adsorbents with adjustable porosities for the broad removal of primary drug pollutants and their metabolites, which are formed as a result of drug transformations in environmental matrices. This keeps adsorbents from building up in the environment and prevents them from becoming significant pollutants in the future. Additionally, it stops secondary pollution caused by the deterioration of the used adsorbents. Focus on the development of effective adsorbents with flexible porosities allows for the complete removal of coexisting contaminants and makes a substantial contribution to wastewater management. In order to concentrate more on the development of flexible pore adsorbents, it is crucial to comprehend the milestones reached in the research and applications of porous magnetic adsorbents based on metal and carbon, which are discussed here.


Assuntos
Carbono , Estruturas Metalorgânicas , Águas Residuárias , Poluentes Químicos da Água , Porosidade , Adsorção , Poluentes Químicos da Água/química , Estruturas Metalorgânicas/química , Carbono/química , Águas Residuárias/química , Purificação da Água/métodos , Metais/química , Preparações Farmacêuticas/química
19.
ACS Appl Mater Interfaces ; 16(25): 32794-32811, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38860871

RESUMO

This paper reports a microfluidic device for the electrochemical and plasmonic detection of cardiac myoglobin (cMb) and cardiac troponin I (cTnI) with noticeable limits of detection (LoD) as low as a few picograms per milliliter (pg/mL) ranges, achieved in a short detection time. The device features two working electrodes, each with a mesoporous Ni3V2O8 nanoscaffold grafted with reduced graphene oxide (rGO) that improves the interaction of diffusing analyte molecules with the sensing surface by providing a high surface area and reaction kinetics. Electrochemical studies reveal sensitivities as high as 9.68 µA ng/mL and a LoD of 2.0 pg/mL for cTnI, and 8.98 µA ng/mL and 4.7 pg/mL for cMb. Additionally, the surface plasmon resonance (SPR) studies demonstrate a low-level LoD of 8.8 pg/mL for cMb and 7.3 pg/mL for cTnI. The dual-modality sensor enables dynamic tracking of kinetic antigen-antibody interactions during sensing, self-verification through providing signals of two modes, and reduced false readout. This study demonstrates the complementary nature of the electrochemical and SPR modes in biosensing, with the electrochemical mode being highly sensitive and the SPR mode providing superior tracking of molecular recognition behaviors. The presented sensor represents a significant innovation in cardiovascular disease management and can be applied to monitor other clinically important biomolecules.


Assuntos
Técnicas Eletroquímicas , Grafite , Infarto do Miocárdio , Mioglobina , Ressonância de Plasmônio de Superfície , Troponina I , Infarto do Miocárdio/diagnóstico , Troponina I/análise , Troponina I/sangue , Grafite/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Mioglobina/análise , Ressonância de Plasmônio de Superfície/instrumentação , Humanos , Porosidade , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Limite de Detecção , Dispositivos Lab-On-A-Chip , Nanoestruturas/química
20.
J Am Chem Soc ; 146(25): 17189-17200, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38864358

RESUMO

Spatial immobilization of fragile enzymes using a nanocarrier is an efficient means to design heterogeneous biocatalysts, presenting superior stability and recyclability to pristine enzymes. An immobilized enzyme, however, usually compromises its catalytic activity because of inevasible mass transfer issues and the unfavorable conformation changes in a confined environment. Here, we describe a synergetic metal-organic framework pore-engineering strategy to trap lipase (an important hydrolase), which confers lipase-boosted stability and activity simultaneously. The hierarchically porous NU-1003, featuring interconnected mesopore and micropore channels, is precisely modified by chain-adjustable fatty acids on its mesopore channel, into which lipase is trapped. The interconnected pore structure ensures efficient communication between trapped lipase and exterior media, while the fatty acid-mediated hydrophobic pore can activate the opening conformation of lipase by interfacial interaction. Such dual pore compartmentalization and hydrophobization activation effects render the catalytic center of trapped lipase highly accessible, resulting in 1.57-fold and 2.46-fold activities as native lipase on ester hydrolysis and enantioselective catalysis. In addition, the feasibility of these heterogeneous biocatalysts for kinetic resolution of enantiomer is also validated, showing much higher efficiency than native lipase.


Assuntos
Estabilidade Enzimática , Enzimas Imobilizadas , Interações Hidrofóbicas e Hidrofílicas , Lipase , Lipase/química , Lipase/metabolismo , Porosidade , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Estruturas Metalorgânicas/química , Hidrólise , Biocatálise
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