RESUMO
This study reports a facile strategy for cancer cell modulated mechanically and electronically tunable hydrogel based on MXene-immobilized hyaluronic acid polymer dot (M-PD). Elevated levels of reactive oxygen species (ROS), such as H2O2 in cancer cells cleave MXene owing to the oxygen-titanium affinity of Ti3C2Tx, altering the physico-mechanical, electrochemical, and fluorescence (FL) properties of the sensor. The H2O2-induced cleavage of M-PD in the hydrogel causes the quenched FL intensity by the Forster resonance energy transfer effect (FRET) to recover, alongside an increase in pore size, influencing shifts in hydrogen bonding and inducing viscoelastic changes in the flexible sensor. This caused physico-mechanical alterations in the sensor, modified the viscosity (G' decreased by 98.7%), and enhanced the stretchability. Further, in vitro electrochemical impedance spectroscopy (EIS) highlighted the distinct results for cancer cells (B16F10: 8.10 kΩ, MDA-MB-231: 8.30 kΩ), and normal cells (CHO-K1: 3.40 kΩ), showcasing electrochemical differentiation between these cells. Additionally, the flexible M-PD hydrogel sensor exhibits high sensitivity, with detection limits of 2.58 cells/well (CHO-K1), 0.96 cells/well (B16F10), and 1.20 cells/well (MDA-MB-231). Finally, real-time cancer monitoring was achieved by integrating the M-PD hydrogel with a wireless setup on a smartphone.
Assuntos
Módulo de Elasticidade , Condutividade Elétrica , Hidrogéis , Hidrogéis/química , Humanos , Porosidade , Polímeros/química , Ácido Hialurônico/química , Animais , Titânio/química , Camundongos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Linhagem Celular Tumoral , Técnicas Biossensoriais/métodos , Pontos Quânticos/químicaRESUMO
Implant-associated infection (IAI) has become an intractable challenge in clinic. The healing of IAI is a complex physiological process involving a series of spatiotemporal connected events. However, existing titanium-based implants in clinic suffer from poor antibacterial effect and single function. Herein, a versatile surface platform based on the presentation of sequential function is developed. Fabrication of titania nanotubes and poly-γ-glutamic acid (γ-PGA) achieves the efficient incorporation of silver ions (Ag+) and the pH-sensitive release in response to acidic bone infection microenvironment. The optimized PGA/Ag platform exhibits satisfactory biocompatibility and converts macrophages from pro-inflammatory M1 to pro-healing M2 phenotype during the subsequent healing stage, which creates a beneficial osteoimmune microenvironment and promotes angio/osteogenesis. Furthermore, the PGA/Ag platform mediates osteoblast/osteoclast coupling through inhibiting CCL3/CCR1 signaling. These biological effects synergistically improve osseointegration under bacterial infection in vivo, matching the healing process of IAI. Overall, the novel integrated PGA/Ag surface platform proposed in this study fulfills function cascades under pathological state and shows great potential in IAI therapy.
Assuntos
Antibacterianos , Ácido Poliglutâmico , Prata , Titânio , Animais , Titânio/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camundongos , Ácido Poliglutâmico/química , Ácido Poliglutâmico/análogos & derivados , Prata/química , Prata/farmacologia , Propriedades de Superfície , Nanotubos/química , Células RAW 264.7 , Infecções Relacionadas à Prótese/tratamento farmacológico , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Cicatrização/efeitos dos fármacos , Próteses e ImplantesRESUMO
Cancer antigen 125 (CA125) is the gold standard biomarker for clinical diagnosis of ovarian cancer, with a threshold value of 35 U/mL in serum. In this paper, a disposable ultrasensitive immunosensor based on Ti3C2Tx-MXene/amino-functionalized carbon nanotube (NH2-CNT) modified screen-printed carbon electrode (SPCE) was constructed for the detection of the ovarian cancer antigen CA125. By optimizing the mass ratio of Ti3C2Tx to NH2-CNT, Ti3C2Tx/NH2-CNT composite with excellent electrochemical properties was prepared, which is beneficial for amplifying the initial electrochemical signal. The positively charged NH2-CNT effectively alleviated the stacking problem of Ti3C2Tx, and its amino group also facilitated the covalent immobilization of the capture antibody. Meanwhile, chitosan (CS) with excellent film-forming ability was also used to successfully enhance the adsorption of electrode material, thus improving the stability of the sensor. In addition, CS could further enhance the current signal. The prepared immunosensor exhibited excellent performance in CA125 detection with a wide linear range from 1 mU/mL to 500 U/mL, and good selectivity, reproducibility and lomg-term stability. Furthermore, the immunosensor showed satisfactory results for the detection of CA125 in clinical serum samples, which is promising for the clinical screening, early diagnosis and prognostic examination of ovarian cancer.
Assuntos
Técnicas Biossensoriais , Antígeno Ca-125 , Eletrodos , Nanotubos de Carbono , Neoplasias Ovarianas , Antígeno Ca-125/sangue , Humanos , Nanotubos de Carbono/química , Feminino , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/diagnóstico , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Técnicas Eletroquímicas/métodos , Titânio/química , Limite de Detecção , Anticorpos Imobilizados/imunologia , Anticorpos Imobilizados/química , Proteínas de MembranaRESUMO
Volatile Organic Compounds (VOCs) are highly harmful to human beings and other organisms, and thus the elimination of VOCs is extremely urgent. Here, La-Si co-doped TiO2 microsphere photocatalysts, which were prepared by a hydrothermal method, exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO2. The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers, as verified by the electrochemical results in combination with density functional theory calculations. In addition, the Si dopant changed the microstructure and surface acidity, while the addition of La promoted the separation efficiency of charge carriers. More interestingly, it was found that singlet oxygen was the key species in the activation of molecular dioxygen, and it played a pivotal role in the photocatalytic decomposition of formaldehyde. This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.
Assuntos
Formaldeído , Microesferas , Oxigênio , Oxigênio Singlete , Titânio , Formaldeído/química , Titânio/química , Oxigênio Singlete/química , Oxigênio/química , Catálise , Lantânio/química , Modelos QuímicosRESUMO
The overexpression of interleukin-17A (IL-17A) is closely associated with the pathogenesis of autoimmune diseases and cancer, rendering precise identification of IL-17A level critical for disease diagnosis and prognosis monitoring. In this study, CsPbBr3 nanoclusters (NCs) were embedded in C16H14Br2O6Pb2 organometallic compound (Pb-MA MOC) via a hot injection approach. Through this way, the issue of CsPbBr3 NCs susceptible to decomposition in water was solved, and the photocurrent intensity that is generated by CsPbBr3 was significantly enhanced. A highly sensitive photoelectrochemical (PEC) sensor for detecting IL-17A in human serum was developed using CsPbBr3/Pb-MA as the photoactive material. The electrode was initially modified with CsPbBr3/Pb-MA. Then, antibody-modified Fe3O4 magnetic nanoparticles (MNs) with target analyte IL-17A captured, and IL-17A antibody-modified Au@CuNi diatomic catalyst (DAC) formed sandwich immune complex structure on the electrode. The existence of CuNi DAC led to a substantial reduction in photoelectric signal intensity due to oxidation of ascorbic acid in the supporting electrolyte. The photocurrent intensity exhibited linear correlation with IL-17A concentration within the range 15-750 pg/mL, and achieving an impressive detection limit of 1 pg/mL. Moreover, the sensor was successfully applied to the determination of IL-17A in human serum, suggesting its potential clinical applications.
Assuntos
Técnicas Eletroquímicas , Interleucina-17 , Limite de Detecção , Compostos Organometálicos , Óxidos , Titânio , Humanos , Interleucina-17/sangue , Interleucina-17/imunologia , Técnicas Eletroquímicas/métodos , Titânio/química , Óxidos/química , Imunoensaio/métodos , Compostos Organometálicos/química , Compostos de Cálcio/química , Técnicas Biossensoriais/métodos , Processos Fotoquímicos , Anticorpos Imobilizados/imunologia , Nanopartículas de Magnetita/química , Ouro/química , EletrodosRESUMO
This study investigated the modification of polyethersulfone (PES) ultrafiltration membranes with TiO2 and Fe2O3-TiO2 nanoparticles to enhance their hydrophilicity and biofouling resistance against the marine microalgae Chlorella vulgaris. It is a common freshwater and marine microalga that readily forms biofilms on membrane surfaces, leading to significant flux decline and increased operational costs in ultrafiltration processes. The microalgae cells and their extracellular polymeric substances (EPS) adhere to the membrane surface, creating a dense fouling layer that impedes water permeation. The modified membranes were characterized using contact angle measurements, scanning electron microscopy, and pure water flux/resistance tests. Short-term ultrafiltration experiments evaluated the membranes' antifouling performance by measuring flux decline, flux recovery ratio, and relative flux reduction during C. vulgaris filtration. The TiO2 membrane showed improved hydrophilicity and antifouling over the pristine PES membrane, while the Fe2O3-TiO2 nanocomposite membrane exhibited the best performance. It reduced the water contact angle and showed only a 5% relative flux reduction compared to 60% for the pristine membrane. SEM images confirmed reduced microalgal deposition on the nanocomposite surface. Long-term tests with microalgal cells under dark and visible light conditions in saline water further assessed the membranes' biofouling resistance. The Fe2O3-TiO2 membrane maintained 59 L/m2 h water flux under visible light after immersion in the microalgal solution, outperforming the pristine (38 L/m2 h) and TiO2 (52 L/m2 h) membranes. This superior antifouling was attributed to photocatalytic generation of reactive oxygen species inhibiting microalgal adhesion. This study demonstrates a promising strategy for mitigating biofouling in membrane-based water treatment and desalination processes.
Assuntos
Incrustação Biológica , Chlorella vulgaris , Compostos Férricos , Luz , Membranas Artificiais , Polímeros , Sulfonas , Titânio , Ultrafiltração , Incrustação Biológica/prevenção & controle , Titânio/química , Titânio/farmacologia , Polímeros/química , Sulfonas/química , Sulfonas/farmacologia , Ultrafiltração/métodos , Compostos Férricos/química , Compostos Férricos/farmacologia , Chlorella vulgaris/efeitos dos fármacos , Nanopartículas/químicaRESUMO
Resection of thoracic wall tumors results in significant defects in the chest wall, leading to various complications. In recent years, the use of three-dimensional (3D) printed titanium alloy prostheses in clinical practice has demonstrated enhanced outcomes in chest wall reconstruction surgery. A cohort of seven patients with sternal tumors was identified for this study. Following a helical CT scan, a digital model was generated for the design of the prosthesis. Subsequently, the tumors were then removed together with the affected sternum and ribs. The chest wall was then reconstructed using 3D-printed titanium alloy prosthesis for bone reconstruction, mesh for pleural reconstruction, and flap for soft tissue reconstruction. Patients were monitored for a period of one year post-surgery. In the seven cases examined, the tumors were found in various locations with varying degrees of invasion. Based on the scope of surgical resection and the size of the defect, 3D-printed titanium alloy prosthesis was custom-designed for chest wall reconstruction. Prior to bone reconstruction, pleural reconstruction was achieved with Bard Composix E/X Mesh, while soft tissue repair involved muscle flap and musculocutaneous flap procedures. A one-year follow-up assessment revealed that the utilization of the 3D-printed titanium alloy prosthesis led to secure fixation, favorable histocompatibility, and enhanced lung function. The findings demonstrate that the utilization of 3D printed titanium alloy prostheses represents a significant advancement in the field of chest wall reconstruction and thoracic surgical procedures.
Assuntos
Neoplasias Ósseas , Procedimentos de Cirurgia Plástica , Impressão Tridimensional , Esterno , Parede Torácica , Titânio , Humanos , Masculino , Parede Torácica/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Pessoa de Meia-Idade , Feminino , Esterno/cirurgia , Neoplasias Ósseas/cirurgia , Idoso , Neoplasias Torácicas/cirurgia , Desenho de Prótese , AdultoRESUMO
Excessive production of reactive oxygen species (ROS) around titanium implants under diabetic conditions causes persistent inflammation, leading to poor osseointegration and even implant failure. Surface modification is an effective way to promote ROS clearance, alleviate inflammation, and stimulate bone formation. In this study, a multifunctional coating is fabricated by introducing cerium (Ce)-containing mesoporous bioactive glass nanoparticles (Ce-MBGNs) onto the titanium surface via an electrophoretic deposition method. The incorporation of Ce-MBGNs remarkably improves surface hydrophilicity by increasing the surface areas. The bioactive ions are appropriately released, thereby promoting mesenchymal stem cell proliferation and differentiation under diabetic conditions. The conversion between Ce(III) and Ce(IV) endows Ce-MBGNs coating with antioxidative nanoenzymes properties to scavenge diabetes-induced ROS, resulting in macrophage polarization towards the anti-inflammatory phenotype. The therapeutic effect of Ce-MBGNs-modified titanium implants is also verified in diabetic rats by inhibiting inflammatory responses and accelerating early osseointegration. Taken together, the findings reveal that the ROS-scavenging and immunomodulation activity of the Ce-MBGNs coating contributes to enhanced osseointegration, and provides a novel implant surface for diabetic patients.
Assuntos
Cério , Diabetes Mellitus Experimental , Células-Tronco Mesenquimais , Nanopartículas , Osseointegração , Espécies Reativas de Oxigênio , Titânio , Cério/química , Cério/farmacologia , Osseointegração/efeitos dos fármacos , Animais , Espécies Reativas de Oxigênio/metabolismo , Ratos , Titânio/química , Titânio/farmacologia , Nanopartículas/química , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos Sprague-Dawley , Próteses e Implantes , Propriedades de Superfície , Porosidade , Proliferação de Células/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Camundongos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/químicaRESUMO
Immunotherapy stands as a groundbreaking strategy for cancer treatment, due to its ability to precisely and safely detect and eradicate tumors. However, the efficacy of immunotherapy is often limited by tumor autophagy, a natural defense mechanism that tumors exploit to resist immune attacks. Herein, we introduce a spatiotemporally controlled method to modulate tumor autophagy via sonocatalysis, aiming to improve immunotherapeutic outcomes. Specifically, we synthesized a tumor-targeting nanocatalyst based on a semiconductor heterojunction composed of Barium Titanate (BTO), Black Phosphorus (BP) integrated with Hyaluronic Acid (HA), referred to as BTO/BP-HA. Compared to traditional catalysts, the heterojunction structure enhances energy band bending and rapid electron-hole separation under ultrasonic stimulation, splitting water to generate H2. This promotes tumor cell apoptosis by inhibiting mitochondrial respiration and induces immunogenic cell death, triggering immune responses to eliminate tumor cells. However, the concurrent activation of autophagy mitigates the cytotoxic effectiveness of nanocatalysts. Within the nanocatalyst, BP undergoes lysosomal degradation to generate PO43-, which subsequently interacts with H+ to generate a conjugated acidic anion, increasing the lysosomal pH. This research ingeniously combines sonocatalysis with tumor autophagy, disrupting the activity of acidic hydrolases to inhibit autophagy, thereby enhancing the immune response and improving the effectiveness of immunotherapy.
Assuntos
Autofagia , Imunoterapia , Autofagia/efeitos dos fármacos , Humanos , Camundongos , Catálise , Animais , Neoplasias/terapia , Neoplasias/imunologia , Neoplasias/patologia , Apoptose/efeitos dos fármacos , Ácido Hialurônico/química , Ácido Hialurônico/farmacologia , Linhagem Celular Tumoral , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Titânio/química , Titânio/farmacologia , Fósforo/química , SemicondutoresRESUMO
Accurate diagnosis of highly aggressive and deadly tumors is essential for effective treatment and improved patient outcomes, and microRNAs (miRNAs) have emerged as crucial biomarkers for their roles in tumor initiation, progression, and metastasis. Herein, we present an on-site visualization colorimetric assay for tumor-associated miRNAs using ruthenium nanoparticle decorated titanium dioxide nanoribbon (Ru@TiO2) as a peroxidase-like (POD) nanozyme. Remarkably, the Ru@TiO2 nanozyme can catalyze the oxidation of chromogenic substrates through its POD-like activity, which is effectively inhibited by pyrophosphate generated during the rolling circle amplification process, thereby enabling miRNA detection through a visible colorimetric readout. This approach provides a highly sensitive and specificity assay for miRNAs in diluted human serum with a detection limit of 100 pM. It shows great potential for clinical diagnostics and biological research, offering a promising tool for early cancer diagnosis and molecular diagnostics.
Assuntos
Colorimetria , MicroRNAs , Rutênio , Titânio , Titânio/química , Humanos , MicroRNAs/análise , MicroRNAs/sangue , MicroRNAs/metabolismo , Rutênio/química , Neoplasias/diagnóstico , Nanopartículas Metálicas/química , Peroxidase/metabolismo , Peroxidase/química , Limite de Detecção , Catálise , Oxirredução , Biomarcadores Tumorais/sangueRESUMO
Inhalation of nanosized metal oxides may occur at the workplace. Thus, information on potential hazardous effects is needed for risk assessment. We report an investigation of the genotoxic potential of different metal oxide nanomaterials. Acellular and intracellular reactive oxygen species (ROS) production were determined for all the studied nanomaterials. Moreover, mice were exposed by intratracheal instillation to copper oxide (CuO) at 2, 6, and 12 µg/mouse, tin oxide (SnO2) at 54 and 162 µg/mouse, aluminum oxide (Al2O3) at 18 and 54 µg/mouse, zinc oxide (ZnO) at 0.7 and 2 µg/mouse, titanium dioxide (TiO2) and the benchmark carbon black at 162 µg/mouse. The doses were selected based on pilot studies. Post-exposure time points were 1 or 28 days. Genotoxicity, assessed as DNA strand breaks by the comet assay, was measured in lung and liver tissue. The acellular and intracellular ROS measurements were fairly consistent. The CuO and the carbon black bench mark particle were potent ROS generators in both assays, followed by TiO2. Al2O3, ZnO, and SnO2 generated low levels of ROS. We detected no increased genotoxicity in this study using occupationally relevant dose levels of metal oxide nanomaterials after pulmonary exposure in mice, except for a slight increase in DNA damage in liver tissue at the highest dose of CuO. The present data add to the body of evidence for risk assessment of these metal oxides.
Assuntos
Cobre , Dano ao DNA , Pulmão , Espécies Reativas de Oxigênio , Titânio , Animais , Camundongos , Titânio/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Dano ao DNA/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Cobre/toxicidade , Ensaio Cometa , Exposição por Inalação/efeitos adversos , Óxido de Zinco/toxicidade , Masculino , Óxido de Alumínio/toxicidade , Compostos de Estanho/toxicidade , Fígado/efeitos dos fármacos , Fígado/metabolismo , Óxidos/toxicidade , Fuligem/toxicidade , Nanopartículas Metálicas/toxicidade , Mutagênicos/toxicidadeRESUMO
BACKGROUND: The prevailing paradigm posits orthodontic tooth movement (OTM) as primarily a localized inflammatory process. In this study, we endeavor to elucidate the potential ramifications of mechanical force on systemic immunity, employing a time-dependent approach. MATERIALS AND METHODS: A previously described mouse orthodontic model was used. Ni-Ti. springs were set to move the upper 1st-molar in C57BL/6 mice and the amount of OTM was. measured by µCT. Mice were allocated randomly into four experimental groups, each. corresponding to clinical phases of OTM, relative to force application. Terminal blood. samples were collected and a comprehensive blood count test for 7 cell types as well as. proteome profiling of 111 pivotal cytokines and chemokines were conducted. Two controls. groups were included: one comprised non-treated mice and the other mice with inactivated springs. RESULTS: Serum immuno-profiling unveiled alterations in cellular immunity, manifesting as. changes in percentages of leukocytes, monocytes, macrophages, neutrophils, and. lymphocytes, alongside key signaling factors in comparison to both control groups. The systemic cellular and molecular alterations triggered by OTM mirrored the dynamics previously described in the local immune response. CONCLUSIONS: Although the exact interplay between local and systemic immune responses to orthodontic forces require further elucidation, our findings demonstrate a tangible link between the two. Future investigations should aim to correlate these results with human subjects, and strive to delve deeper into the specific mechanisms by which mechanical force modulates the systemic immune response.
Assuntos
Camundongos Endogâmicos C57BL , Técnicas de Movimentação Dentária , Técnicas de Movimentação Dentária/métodos , Animais , Camundongos , Citocinas , Imunidade Celular , Microtomografia por Raio-X , Macrófagos/imunologia , Níquel , Neutrófilos/imunologia , Distribuição Aleatória , Quimiocinas/sangue , TitânioRESUMO
BACKGROUND: Total hip arthroplasty in patients with rheumatoid arthritis is difficult and leads to worse implant survival and higher risk for complications compared to osteoarthritis. Poor periacetabular bone quality might challenge the stability of the acetabular cup. Contemporary 3D-printed highly-porous titanium cup designs have become the benchmark for cementless implants; however, their usefulness in rheumatoid arthritis is still unclear. The purpose of this study was to assess the short-term results of the use of a highly-porous 3D-printed acetabular titanium cup in patients with rheumatoid arthritis. MATERIAL AND METHODS: We studied a consecutive series of RA patients who underwent cementless THA between 2019 and 2020 in our center with the same 3D-printed highly-porous titanium acetabular cup. All patients were evaluated prospectively for a minimum 3-year follow-up with the Harris hip score, VAS and Roles and Maudsley score. Radiographic assessment focused on evidence of cup osseointegration. RESULTS: 37 RA patients, mean age at surgery of 51.3 years, were included. Mean follow-up was 3.2 years (3 to 4 years). By the last follow-up visit, the Harris hip score had increased significantly from 37.8 to 88.5, VAS had decreased from 6.1 to 1.0 and excellent satisfaction for 31 patients. All 5 Moore's radiographic signs were present in 35 hips, with only 4 signs present in the remaining 2 hips, thus indicating complete osseointegration of all cups. There were no complications on the acetabular side but one intraoperative proximal calcar fracture. CONCLUSION: 3D-printed highly porous implants used in primary THA worked well in patients with rheumatoid arthritis, showing excellent osseointegration and good clinical results in the short term.
Assuntos
Acetábulo , Artrite Reumatoide , Artroplastia de Quadril , Prótese de Quadril , Desenho de Prótese , Humanos , Artrite Reumatoide/cirurgia , Feminino , Artroplastia de Quadril/métodos , Artroplastia de Quadril/instrumentação , Masculino , Pessoa de Meia-Idade , Acetábulo/cirurgia , Adulto , Idoso , Titânio , Resultado do Tratamento , Porosidade , Impressão Tridimensional , Estudos ProspectivosRESUMO
OBJECTIVE: For analyzing the mechanical properties of 2 cranio-orbital repair materials under distinct external impacts by finite element analysis and evaluating the stability of various repair materials. METHODS: Based on the computed tomography images of the patients with cranio-orbital fractures, three-dimensional models of the normal craniomaxillofacial models were established by segmenting them with Mimics 19.0, Geomagic Studio 12.0, and UG 12.0, respectively, to build the finite element models of titanium repair fixation and the poly-ether-ether-ketone repair fixation. The models were then simulated by Ansys 19.2, with divergent impact forces to analyze the stresses and displacements of the repair materials, as well as the internal fixation system, and to make a comparison on the stability of the distinct repair materials. RESULTS: The titanium mesh is stable at impact forces ≤1500 N. Furthermore, the poly-ether-ether-ketone mesh and the internal fixation system are resistant to fracture and displacement at impact forces of up to 3000 N. CONCLUSION: By simulating distinct mechanical environments, the biomechanical finite element analysis method can digitally assess the mechanical properties of cranio-orbital repair materials and objectively evaluate the stability of the repair materials and the internal fixation system.
Assuntos
Benzofenonas , Análise de Elementos Finitos , Fixação Interna de Fraturas , Cetonas , Fraturas Orbitárias , Telas Cirúrgicas , Titânio , Tomografia Computadorizada por Raios X , Humanos , Fraturas Orbitárias/cirurgia , Fraturas Orbitárias/diagnóstico por imagem , Fenômenos Biomecânicos , Cetonas/química , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Polietilenoglicóis/química , Polímeros , Teste de Materiais , Imageamento Tridimensional , Estresse Mecânico , Modelos Anatômicos , Simulação por ComputadorRESUMO
An extracellular matrix protein, fibronectin (Fn), was covalently immobilized on 316L stainless steel, L605 cobalt chromium (CoCr), and nickel titanium (NiTi) surfaces through an 11-mercaptoundecanoic acid (MUA) self-assembled monolayer (SAM) pre-formed on these surfaces. Polarization modulation infrared reflection adsorption spectroscopy (PM-IRRAS) confirmed the presence of Fn on the surfaces. The Fn monolayer attached to the SAM was found to be stable under fluid shear stress. Deconvolution of the Fn amide I band indicated that the secondary structure of Fn changes significantly upon immobilization to the SAM-functionalized metal substrate. Scanning electron microscopy and energy dispersive X-ray analysis revealed that the spacing between Fn molecules on a modified commercial stent surface is approximately 66 nm, which has been reported to be the most appropriate spacing for cell/surface interactions.
Assuntos
Fibronectinas , Níquel , Aço Inoxidável , Stents , Propriedades de Superfície , Titânio , Fibronectinas/química , Aço Inoxidável/química , Níquel/química , Titânio/química , Materiais Biocompatíveis/química , Proteínas Imobilizadas/química , Compostos de Sulfidrila/química , Cobalto/química , Humanos , Adsorção , Ácidos Graxos/química , Cromo/químicaRESUMO
BACKGROUND: It is well-known that nanoparticles sediment, diffuse and aggregate when dispersed in a fluid. Once they approach a cell monolayer, depending on the affinity or "stickiness" between cells and nanoparticles, they may adsorb instantaneously, settle slowly - in a time- and concentration-dependent manner - or even encounter steric hindrance and rebound. Therefore, the dose perceived by cells in culture may not necessarily be that initially administered. Methods for quantifying delivered dose are difficult to implement, as they require precise characterization of nanoparticles and exposure scenarios, as well as complex mathematical operations to handle the equations governing the system dynamics. Here we present a pipeline and a graphical user interface, DosiGUI, for application to the accurate nano-dosimetry of engineered nanoparticles on cell monolayers, which also includes methods for determining the parameters characterising nanoparticle-cell stickiness. RESULTS: We evaluated the stickiness for 3 industrial nanoparticles (TiO2 - NM-105, CeO2 - NM-212 and BaSO4 - NM-220) administered to 3 cell lines (HepG2, A549 and Caco-2) and subsequently estimated corresponding delivered doses. Our results confirm that stickiness is a function of both nanoparticle and cell type, with the stickiest combination being BaSO4 and Caco-2 cells. The results also underline that accurate estimations of the delivered dose cannot prescind from a rigorous evaluation of the affinity between the cell type and nanoparticle under investigation. CONCLUSION: Accurate nanoparticle dose estimation in vitro is crucial for in vivo extrapolation, allowing for their safe use in medical and other applications. This study provides a computational platform - DosiGUI - for more reliable dose-response characterization. It also highlights the importance of cell-nanoparticle stickiness for better risk assessment of engineered nanomaterials.
Assuntos
Simulação por Computador , Humanos , Células CACO-2 , Células A549 , Titânio/toxicidade , Titânio/química , Cério/toxicidade , Cério/química , Nanopartículas/toxicidade , Nanopartículas/química , Células Hep G2 , Relação Dose-Resposta a Droga , Modelos Biológicos , Tamanho da PartículaRESUMO
Exploring the structural basis of membrane proteins is significant for a deeper understanding of protein functions. In situ analysis of membrane proteins and their dynamics, however, still challenges conventional techniques. Here we report the first attempt to immobilize membrane protein complexes on surface-enhanced Raman scattering (SERS)-active supports, titanium dioxide-coated silver (Ag@TiO2) nanoparticles. Biocompatible immobilization of microsomal monooxygenase complexes is achieved through lipid fission and fusion. SERS activity of the Ag@TiO2 nanoparticles enables in situ monitoring of protein-protein electron transfer and enzyme catalysis in real time. Through SERS fingerprints of the monooxygenase redox centers, the correlations between these protein-ligand interactions and reactive oxygen species generation are revealed, providing novel insights into the molecular mechanisms underlying monooxygenase-mediated apoptotic regulation. This study offers a novel strategy to explore structure-function relationships of membrane protein complexes and has the potential to advance the development of novel reactive oxygen species-inducing drugs for cancer therapy.
Assuntos
Proteínas de Membrana , Nanopartículas Metálicas , Espécies Reativas de Oxigênio , Prata , Análise Espectral Raman , Titânio , Titânio/química , Análise Espectral Raman/métodos , Prata/química , Proteínas de Membrana/química , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas Metálicas/química , Humanos , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Proteínas Imobilizadas/química , Nanoestruturas/químicaRESUMO
Aflatoxin B1 (AFB1) is a highly toxic carcinogen severely harmful to humans and animals. This study fabricated SDB-6-K-9@TiO2 composites via the hydrothermal synthesis method to reduce AFB1. The structural characterization results of the photocatalytic composites showed that TiO2 was successfully loaded onto SDB-6-K-9. The different photocatalytic degradation conditions, photocatalyst kinetics, recycling performance, and photocatalytic degradation mechanism were investigated. Photocatalysis with 6 mg of 4%SDB-6-K-9@TiO2 in a 100 µg/mL AFB1 solution presented a reduction of over 95%, exhibiting excellent performance, high stability, and reusability even after five cycles of photocatalytic experiments. Active species trapping experiments confirmed that holes (h+) played the most critical role. After structural analysis and identification of the photocatalytic degradation products, the photodegradation path and photocatalytic oxidation mechanism of 4%SDB-6-K-9@TiO2 were postulated. The results show a new way to improve TiO2's photocatalytic performance, providing a certain theoretical basis for the effective AFB1 reduction.
Assuntos
Aflatoxina B1 , Carvão Vegetal , Glycine max , Fotólise , Luz Solar , Titânio , Titânio/química , Aflatoxina B1/química , Aflatoxina B1/efeitos da radiação , Catálise , Carvão Vegetal/química , Glycine max/químicaRESUMO
BACKGROUND: The utilization of titanium dioxide nanoparticles (TiO2 NPs) has significantly increased across various industries. OBJECTIVES: This study rigorously explored the impact of TiO2 NPs exposure on chicken embryos, focusing particularly on alterations in the immune system, liver functionality and key biochemical markers. METHODS: The study involved three groups of 30 eggs each, subjected to increasing doses of TiO2 NPs: Group C (control), Group T1 (150 µg/mL) and Group T2 (300 µg/mL). After 48 h of incubation, the eggs in Groups T1 and T2 each received an injection of 0.3 mL of the TiO2 NPs solution. In contrast, the eggs in the control group (Group C) were injected with 0.3 mL of saline solution. Histopathological changes were analysed using haematoxylin and eosin (H&E) staining, whereas amniotic fluid's biochemical properties were examined photometrically. The study also assessed the expression of immune genes (AvBD9, IL6 and IL8L2) through quantitative PCR. The evaluations included growth metrics, amniotic fluid biochemistry and histological analysis of the liver, caecal tonsil and bursa of Fabricius. RESULTS: The results revealed subcutaneous haemorrhage, significant reductions in total body weight and marked changes in biochemical markers, including urea, creatinine, alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), in the amniotic fluid of the groups treated with TiO2 NPs, compared to the control. Histological examinations indicated noticeable alterations in the liver, caecal tonsil and bursa of Fabricius following TiO2 NP exposure. These alterations were characterized by disruptions in cellular structures and variations in lymphocyte counts. Furthermore, a notable decrease in the expression of immunity genes, namely, AvBD9, IL8L2 and IL6, was observed in the TiO2 NP-treated groups compared to the control. CONCLUSION: The findings underscore the need for risk assessments of TiO2 NPs exposure due to its impact on development and immunity. Future research should explore its impact on neurodevelopment and degeneration.
Assuntos
Fígado , Titânio , Animais , Titânio/toxicidade , Embrião de Galinha/efeitos dos fármacos , Fígado/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Nanopartículas , Galinhas/crescimento & desenvolvimentoRESUMO
Sonodynamic therapy (SDT) as a non-invasive antitumor strategy has been widely concerned. However, the rapid electron (e-) and hole (h+) recombination of traditional inorganic semiconductor sonosensitizers under ultrasonic (US) stimulation greatly limits the production of reactive oxygen species (ROS). Herein, we report a unique Zn/Pt dual-site single-atom driven difunctional superimposition-augmented TiO2-based sonosensitizer (Zn/Pt SATs). Initially, we verify through theoretical calculation that the strongly coupled Zn and Pt atoms can assist electron excitation at the atomic level by increasing electron conductivity and excitation efficiency under US, respectively, thus effectively improving the yield of ROS. Additionally, Zn/Pt SATs can significantly enhance ferroptosis by producing more ROS and sonoexcited holes under US stimuli. Therefore, the establishment of dual-site single-atom system represents an innovative strategy to enhance SDT in cancer model of female mice and provides a typical example for the development of inorganic sonosensitizer in the field of antitumor therapy.