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1.
J Environ Sci (China) ; 147: 561-570, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003071

RESUMEN

In the present study, we investigated the influence of surface fluorine (F) on TiO2 for the photocatalytic oxidation (PCO) of toluene. TiO2 modified with different F content was prepared and tested. It was found that with the increasing of F content, the toluene conversion rate first increased and then decreased. However, CO2 mineralization efficiency showed the opposite trend. Based on the characterizations, we revealed that F substitutes the surface hydroxyl of TiO2 to form the structure of Ti-F. The presence of the appropriate amount of surface Ti-F on TiO2 greatly enhanced the separation of photogenerated carriers, which facilitated the generation of ·OH and promoted the activity for the PCO of toluene. It was further revealed that the increase of only ·OH promoted the conversion of toluene to ring-containing intermediates, causing the accumulation of intermediates and then conversely inhibited the ·OH generation, which led to the decrease of the CO2 mineralization efficiency. The above results could provide guidance for the rational design of photocatalysts for toluene oxidation.


Asunto(s)
Fluoruros , Oxidación-Reducción , Titanio , Tolueno , Tolueno/química , Titanio/química , Catálisis , Fluoruros/química , Procesos Fotoquímicos , Modelos Químicos
2.
J Environ Sci (China) ; 148: 476-488, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095182

RESUMEN

In this study, non-thermal plasma (NTP) was employed to modify the Cu/TiO2 adsorbent to efficiently purify H2S in low-temperature and micro-oxygen environments. The effects of Cu loading amounts and atmospheres of NTP treatment on the adsorption-oxidation performance of the adsorbents were investigated. The NTP modification successfully boosted the H2S removal capacity to varying degrees, and the optimized adsorbent treated by air plasma (Cu/TiO2-Air) attained the best H2S breakthrough capacity of 113.29 mg H2S/gadsorbent, which was almost 5 times higher than that of the adsorbent without NTP modification. Further studies demonstrated that the superior performance of Cu/TiO2-Air was attributed to increased mesoporous volume, more exposure of active sites (CuO) and functional groups (amino groups and hydroxyl groups), enhanced Ti-O-Cu interaction, and the favorable ratio of active oxygen species. Additionally, the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicated the main reason for the deactivation was the consumption of the active components (CuO) and the agglomeration of reaction products (CuS and SO42-) occupying the active sites on the surface and the inner pores of the adsorbents.


Asunto(s)
Cobre , Sulfuro de Hidrógeno , Oxidación-Reducción , Titanio , Titanio/química , Adsorción , Cobre/química , Sulfuro de Hidrógeno/química , Contaminantes Atmosféricos/química , Gases em Plasma/química , Modelos Químicos
3.
J Environ Sci (China) ; 148: 515-528, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095185

RESUMEN

The reduction of nitrobenzene to aniline is very important for both pollution control and chemical synthesis. Nevertheless, difficulties still remain in developing a catalytic system having high efficiency and selectivity for the production of aniline. Herein, it was found that PdO nanoparticles highly dispersed on TiO2 support (PdO/TiO2) functioned as a highly efficient catalyst for the reduction of nitrobenzene in the presence of NaBH4. Under favorable conditions, 95% of the added nitrobenzene (1 mmol/L) was reduced within 1 min with an ultra-low apparent activation energy of 10.8 kJ/mol by using 0.5%PdO/TiO2 as catalysts and 2 mmol/L of NaBH4 as reductants, and the selectivity to aniline even reached up to 98%. The active hydrogen species were perceived as dominant species during the hydrogenation of nitrobenzene by the results of isotope labeling experiments and ESR spectroscopic. A mechanism was proposed as follows: PdO activates the nitro groups and leads to in-situ generation of Pd, and the generated Pd acts as the reduction sites to produce active hydrogen species. In this catalytic system, nitrobenzene prefers to be adsorbed on the PdO nanoparticles of the PdO/TiO2 composite. Subsequently, the addition of NaBH4 results in in-situ generation of a Pd/PdO/TiO2 composite from the PdO/TiO2 composite, and the Pd nanoclusters would activate NaBH4 to generate active hydrogen species to attack the adsorbed nitro groups. This work will open up a new approach for the catalytic transfer hydrogenation of nitrobenzene to aniline in green chemistry.


Asunto(s)
Compuestos de Anilina , Nitrobencenos , Paladio , Titanio , Nitrobencenos/química , Compuestos de Anilina/química , Titanio/química , Hidrogenación , Catálisis , Paladio/química , Modelos Químicos
4.
J Environ Sci (China) ; 148: 57-68, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095190

RESUMEN

The expandable graphite (EG) modified TiO2 nanocomposites were prepared by the high shear method using the TiO2 nanoparticles (NPs) and EG as precursors, in which the amount of EG doped in TiO2 was 10 wt.%. Followed by the impregnation method, adjusting the pH of the solution to 10, and using the electrostatic adsorption to achieve spatial confinement, the Pt elements were mainly distributed on the exposed TiO2, thus generating the Pt/10EG-TiO2-10 catalyst. The best CO oxidation activity with the excellent resistance to H2O and SO2 was obtained over the Pt/10EG-TiO2-10 catalyst: CO conversion after 36 hr of the reaction was ca. 85% under the harsh condition of 10 vol.% H2O and 100 ppm SO2 at a high gaseous hourly space velocity (GHSV) of 400,000 hr-1. Physicochemical properties of the catalysts were characterized by various techniques. The results showed that the electrostatic adsorption, which riveted the Pt elements mainly on the exposed TiO2 of the support surface, reduced the dispersion of Pt NPs on EG and achieved the effective dispersion of Pt NPs, hence significantly improving CO oxidation activity over the Pt/10EG-TiO2-10 catalyst. The 10 wt.% EG doped in TiO2 caused the TiO2 support to form a more hydrophobic surface, which reduced the adsorption of H2O and SO2 on the catalyst, greatly inhibited deposition of the TiOSO4 and formation of the PtSO4 species as well as suppressed the oxidation of SO2, thus resulting in an improvement in the resistance to H2O and SO2 of the Pt/10EG-TiO2-10 catalyst.


Asunto(s)
Grafito , Oxidación-Reducción , Platino (Metal) , Dióxido de Azufre , Titanio , Titanio/química , Grafito/química , Dióxido de Azufre/química , Platino (Metal)/química , Catálisis , Monóxido de Carbono/química , Agua/química , Contaminantes Atmosféricos/química , Modelos Químicos
5.
BMC Oral Health ; 24(1): 902, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107737

RESUMEN

BACKGROUND: Long-term success of implant restoration depends on many factors one of them is the sufficient implant stability which is lowered in compromised bone density sites such as the maxilla as it is categorized as type III & IV bone, so searching for a new innovation and updates in implant material and features is very mandatory. So, the aim of this study was to compare between two implant materials (roxolid and traditional titanium) on the primary and secondary stability of implant retained maxillary overdenture. METHODS: Eighteen completely edentulous patients were selected. All patients received maxillary implant-retained overdentures and lower complete dentures; patients were divided equally into two groups according to the type of implant materials. Group A received a total number of 36 implants made of roxolid material and Group B received a total number of 36 implants made of traditional titanium alloys. Implant stability was assessed using ostell device, the primary implant stability was measured at the day of implant installation however, secondary implant stability was measured after six weeks of implant placement. Paired t-test was used to compare between primary and secondary stability in the same group and an independent t-test was used to compare between the two groups with a significant level < 0.05. RESULTS: Independent t-test revealed a significant difference between the two groups with p -value = 0.0141 regarding primary stability and p-value < 0.001 regarding secondary stability, as roxolid implant group was statistically higher stability than titanium group in both. Paired t- test showed a statistically significant difference in roxolid implant group with p-value = 0.0122 however, there was non-statistically significant difference in titanium group with p-value = 0.636. Mann Whitney test showed a significant difference between the two groups regarding amount of change in stability with p value = 0.191. roxolid implant group showed a higher amount of change in stability than the titanium implant group. CONCLUSION: Within the limitation of this study, it could be concluded that: Roxolid implants showed promising results regarding primary and secondary stability compared to conventional Titanium implants and can be a better alternative in implant retained maxillary overdentures. TRIAL REGISTRATION: Retrospectively NCT06334770 at 26-3-2024.


Asunto(s)
Prótesis Dental de Soporte Implantado , Prótesis de Recubrimiento , Maxilar , Titanio , Humanos , Masculino , Femenino , Maxilar/cirugía , Persona de Mediana Edad , Implantes Dentales , Aleaciones Dentales/química , Anciano , Circonio , Retención de Dentadura , Materiales Dentales/química , Aleaciones
6.
J Mater Sci Mater Med ; 35(1): 50, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136804

RESUMEN

The human head can sometimes experience impact loads that result in skull fractures or other injuries, leading to the need for a craniectomy. Cranioplasty is a procedure that involves replacing the removed portion with either autologous bone or alloplastic material. While titanium has traditionally been the preferred material for cranial implants due to its excellent properties and biocompatibility, its limitations have prompted the search for alternative materials. This research aimed to explore alternative materials to titanium for cranial implants in order to address the limitations of titanium implants and improve the performance of the cranioplasty process. A 3D model of a defective skull was reconstructed with a cranial implant, and the implant was simulated using various stiff and soft materials (such as alumina, zirconia, hydroxyapatite, zirconia-reinforced PMMA, and PMMA) as alternatives to titanium under 2000N impact forces. Alumina and zirconia implants were found to reduce stresses and strains on the skull and brain compared to titanium implants. However, PMMA implants showed potential for causing skull damage under current loading conditions. Additionally, PMMA and hydroxyapatite implants were prone to fracture. Despite these findings, none of the implants exceeded the limits for tensile and compressive stresses and strains on the brain. Zirconia-reinforced PMMA implants were also shown to reduce stresses and strains on the skull and brain compared to PMMA implants. Alumina and zirconia show promise as alternatives to titanium for the production of cranial implants. The use of alternative implant materials to titanium has the potential to enhance the success of cranial reconstruction by overcoming the limitations associated with titanium implants.


Asunto(s)
Materiales Biocompatibles , Análisis de Elementos Finitos , Ensayo de Materiales , Procedimientos de Cirugía Plástica , Cráneo , Estrés Mecánico , Titanio , Circonio , Humanos , Cráneo/cirugía , Titanio/química , Materiales Biocompatibles/química , Circonio/química , Procedimientos de Cirugía Plástica/métodos , Prótesis e Implantes , Durapatita/química , Polimetil Metacrilato/química , Óxido de Aluminio/química , Resistencia a la Tracción , Fracturas Craneales/cirugía , Fuerza Compresiva
7.
BMC Oral Health ; 24(1): 946, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39143630

RESUMEN

BACKGROUND: Restorative treatment options for edentulous patients range from traditional dentures to fixed restorations. The proper selection of materials greatly influences the longevity and stability of fixed restorations. Most prosthetic parts are frequently fabricated from titanium. Ceramics (e.g. zirconia) and polymers (e.g. PEEK and BIOHPP) have recently been included in these fabrications. The mandibular movement produces complex patterns of stress and strain. Mandibular fractures may result from these stresses and strains exceeding the critical limits because of the impact force from falls or accidents. Therefore, it is necessary to evaluate the biomechanical behavior of the edentulous mandible with different restorations under different loading situations. OBJECTIVE: This study analyzes the biomechanical behavior of mandibles after four prosthetic restorations for rehabilitation under normal and impact loading scenarios. MATERIAL AND METHODS: The mandibular model was constructed with a fixed restoration, which was simulated using various materials (e.g. Titanium, Zirconia & BIOHPP), under frontal bite force, maximum intercuspation, and chin impact force. From the extraction of tensile and compressive stresses and strains, as well as the total deformation of mandible segments, the biomechanical behavior and clinical situations were studied. RESULTS: Under frontal bite, the anterior body exhibited the highest tensile (60.34 MPa) and compressive (108.81 MPa) stresses using restoration 4, while the condyles and angles had the lowest tensile (7.12 MPa) and compressive (12.67 MPa) stresses using restoration 3. Under maximum intercuspation, the highest tensile (40.02 MPa) and compressive (98.87 MPa) stresses were generated on the anterior body of the cortical bone using restoration 4. Additionally, the lowest tensile (7.7 MPa) and compressive (10.08 MPa) stresses were generated on the condyles and angles, respectively, using restoration 3. Under chin impact, the highest tensile (374.57 MPa) and compressive (387.3 MPa) stresses were generated on the anterior body using restoration 4. Additionally, the lowest tensile (0.65 MPa) and compressive (0.57 MPa) stresses were generated on the coronoid processes using restoration 3. For all loading scenarios, the anterior body of the mandible had the highest stress and strain values compared with the other segments. Compared to the traditional titanium restoration.2, restoration.1(zirconia) increases the tensile and compressive stresses and strains on the mandibular segments, in contrast to restoration.3 (BIOHPP). In addition, zirconia implants exhibited higher displacements than the other implants. CONCLUSION: In the normal loading scenario, the tensile and compressive stresses and strains on the mandible were within the allowable limits when all restorations were used. Under the chin impact loading scenario, the anterior body of the mandible was damaged by restorations 1 and 4.


Asunto(s)
Fuerza de la Mordida , Mandíbula , Estrés Mecánico , Titanio , Circonio , Humanos , Fenómenos Biomecánicos , Materiales Dentales/química , Polietilenglicoles , Polímeros , Arcada Edéntula/rehabilitación , Benzofenonas , Cetonas , Resistencia a la Tracción , Análisis de Elementos Finitos , Análisis del Estrés Dental , Fuerza Compresiva , Diseño de Dentadura
8.
PLoS One ; 19(8): e0306866, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39146267

RESUMEN

Low-dimensional materials have demonstrated strong potential for use in diverse flexible strain sensors for wearable electronic device applications. However, the limited contact area in the sensing layer, caused by the low specific surface area of typical nanomaterials, hinders the pursuit of high-performance strain-sensor applications. Herein, we report an efficient method for synthesizing TiO2-based nanocomposite materials by directly using industrial raw materials with ultrahigh specific surface areas that can be used for strain sensors. A kinetic study of the self-seeded thermal hydrolysis sulfate process was conducted for the controllable synthesis of pure TiO2 and related TiO2/graphene composites. The hydrolysis readily modified the crystal form and morphology of the prepared TiO2 nanoparticles, and the prepared composite samples possessed a uniform nanoporous structure. Experiments demonstrated that the TiO2/graphene composite can be used in strain sensors with a maximum Gauge factor of 252. In addition, the TiO2/graphene composite-based strain sensor showed high stability by continuously operating over 1,000 loading cycles and aging tests over three months. It also shows that the fabricated strain sensors have the potential for human voice recognition by characterizing letters, words, and musical tones.


Asunto(s)
Grafito , Nanocompuestos , Titanio , Titanio/química , Grafito/química , Humanos , Nanocompuestos/química , Voz , Dispositivos Electrónicos Vestibles
9.
BMC Oral Health ; 24(1): 901, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107754

RESUMEN

BACKGROUND: Mechanical complications affect the stability of implant restorations and are a key concern for clinicians, especially with the frequent introduction of new implant designs featuring various structures and materials. This study evaluated the effect of different prosthetic index structure types and implant materials on the stress distribution of implant restorations using both in silico and in vitro methods. METHODS: Four finite element analysis (FEA) models of implant restorations were created, incorporating two prosthetic index structures (cross-fit (CF) and torc-fit (TF)) and two implant materials (titanium and titanium-zirconium). A static load was applied to each group. An in vitro study using digital image correlation (DIC) with a research scenario identical to that of the FEA was conducted for validation. The primary strain, sensitivity index, and equivalent von Mises stress were used to evaluate the outcomes. RESULTS: Changing the implant material from titanium to titanium-zirconium did not significantly affect the stress distribution or maximum stress value of other components, except for the implant itself. In the CF group, implants with a lower elastic modulus increased the stress on the screw. The TF group showed better stress distribution on the abutment and a lower stress value on the screw. The TF group demonstrated similar sensitivity for all components. DIC analysis revealed significant differences between TF-TiZr and CF-Ti in terms of the maximum (P < 0.001) and minimum principal strains (P < 0.05) on the implants and the minimum principal strains on the investment materials in both groups (P < 0.001). CONCLUSIONS: Changes in the implant material significantly affected the maximum stress of the implant. The TF group exhibited better structural integrity and reliability.


Asunto(s)
Implantes Dentales , Materiales Dentales , Análisis del Estrés Dental , Análisis de Elementos Finitos , Titanio , Circonio , Circonio/química , Humanos , Materiales Dentales/química , Análisis del Estrés Dental/métodos , Estrés Mecánico , Diseño de Prótesis Dental , Módulo de Elasticidad , Simulación por Computador , Imagenología Tridimensional
10.
Mikrochim Acta ; 191(9): 523, 2024 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112841

RESUMEN

An antifouling peptide hydrogel-based electrochemical biosensor was developed for real-time monitoring of hydrogen peroxide (H2O2) and nitric oxide (NO) released by 3D cultured breast cancer cells upon drug stimulation. Platinum nanoparticles (Pt NPs) were electrodeposited on titanium mesh (Pt NPs/TM) to enhance sensitivity and shown to possess excellent electrocatalytic ability toward H2O2 and NO. The composite hydrogel formed by co-assembling of N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF) and a fluorine methoxycarbonyl group-functionalized Lys-(Fmoc)-Asp was coated on Pt NPs/TM electrode surface to provide cellular scaffolding. Their favorable biocompatibility promoted cell adhesion and growth, while good hydrophilicity endowed the sensor with greatly enhanced antifouling capability in complex cell culture environments. The biosensor successfully determined H2O2 and NO secretion from both non-metastatic and metastatic breast cancer cells in real time. Our results demonstrated robust associations between reactive oxygen species (ROS) and reactive nitrogen species (RNS) production and cell malignancy, with the main difference in oxidative stress between the two subtypes of cells being NO release, particularly emphasizing RNS's critical leading in driving cancer metastasis and invasion progression. This sensor holds great potential for cell-release research under the in vivo-like microenvironment and could reveal RNS as an attractive therapeutic target for treating breast cancer.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Técnicas Electroquímicas , Hidrogeles , Peróxido de Hidrógeno , Óxido Nítrico , Platino (Metal) , Humanos , Técnicas Biosensibles/métodos , Peróxido de Hidrógeno/química , Hidrogeles/química , Neoplasias de la Mama/patología , Óxido Nítrico/metabolismo , Óxido Nítrico/análisis , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Platino (Metal)/química , Nanopartículas del Metal/química , Femenino , Péptidos/química , Péptidos/farmacología , Línea Celular Tumoral , Titanio/química , Células MCF-7 , Técnicas de Cultivo Tridimensional de Células/métodos
11.
Int J Nanomedicine ; 19: 7963-7981, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39130689

RESUMEN

Introduction: Traditional cancer treatment strategies often have severe toxic side effects and poor therapeutic efficacy. To address the long-standing problems related to overcoming the complexity of tumors, we develop a novel nanozyme based on the in situ oxidation of 2D Ti3C2 structure to perform simultaneous phototherapy and sonodynamic therapy on tumors. Ti3C2 nanozymes exhibit multi-enzyme activity, including intrinsic peroxidase (POD) activities, which can react with H2O2 in the tumor microenvironment. This new material can construct Ti3C2/TiO2 heterostructures in vivo. Methods: Photothermal (PTT), sonodynamic (SDT) effects, and photoacoustic (PA) image-guided synergy therapy can be achieved. Finally, anticancer immune responses occur with this nanozyme. In vivo experiments revealed that the Ti3C2/TiO2 heterostructure inhibited tumor growth. Results: Complementarily, our results showed that the Ti3C2/TiO2 heterostructure enhanced the immunogenic activity of tumors by recruiting cytotoxic T cells, thereby enhancing the tumor ablation effect. Mechanistic studies consistently indicated that Reactive Oxygen Species (ROS) regulates apoptosis of HCC cells by modulating NRF2/OSGIN1 signaling both in vitro and in vivo. As a result, Ti3C2 nanozyme effectively inhibited tumor through its synergistic ability to modulate ROS and enhance immune infiltration of cytotoxic T cells in the tumor microenvironment. Discussion: These findings open up new avenues for enhancing 2D Ti3C2 nanosheets and suggest a new way to develop more effective sonosensitizers for the treatment of cancer.


Asunto(s)
Titanio , Terapia por Ultrasonido , Titanio/química , Titanio/farmacología , Animales , Ratones , Humanos , Terapia por Ultrasonido/métodos , Nanopartículas/química , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Microambiente Tumoral/efectos de los fármacos , Fototerapia/métodos , Ratones Endogámicos BALB C , Apoptosis/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamiento farmacológico , Técnicas Fotoacústicas/métodos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Int J Nanomedicine ; 19: 8015-8027, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39130690

RESUMEN

Purpose: This study aimed to confirm the synergy effect of these two materials by evaluating osteoblast and antibacterial activity by applying a double-layered hydroxyapatite(HA) zirconium oxide(ZrO2) coating to titanium. Methods: The specimens used in this study were divided into four groups: a control group (polished titanium; group T) and three experimental groups: Group TH (RF magnetron sputtered HA deposited titanium), Group Z (ZrO2 ALD deposited titanium), and Group ZH (RF magnetron sputtered HA and ZrO2 ALD deposited titanium). The adhesion of Streptococcus mutans (S.mutans) to the surface was assessed using a crystal violet assay. The adhesion, proliferation, and differentiation of MC3T3-E1 cells, a mouse osteoblastic cell line, were assessed through a WST-8 assay and ALP assay. Results: Group Z showed a decrease in the adhesion of S. mutans (p < 0.05) and an improvement in osteoblastic viability (p < 0.0083). Group TH and ZH showed a decrease in adhesion of S. mutans (p < 0.05) and an increase in osteoblastic cell proliferation and cell differentiation (p < 0.0083). Group ZH exhibited the highest antibacterial and osteoblastic differentiation. Conclusion: In conclusion double-layered HA and ZrO2 deposited on titanium were shown to be more effective in inhibiting the adhesion of S. mutans, which induced biofilm formation, and increasing osteoblastic differentiation involved in osseointegration by the synergistic effect of the two materials.


Asunto(s)
Adhesión Bacteriana , Diferenciación Celular , Proliferación Celular , Materiales Biocompatibles Revestidos , Durapatita , Osteoblastos , Streptococcus mutans , Propiedades de Superficie , Titanio , Circonio , Circonio/química , Circonio/farmacología , Titanio/química , Titanio/farmacología , Streptococcus mutans/efectos de los fármacos , Animales , Ratones , Durapatita/química , Durapatita/farmacología , Osteoblastos/efectos de los fármacos , Osteoblastos/citología , Proliferación Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Línea Celular , Antibacterianos/farmacología , Antibacterianos/química , Adhesión Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos
13.
Lasers Med Sci ; 39(1): 206, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39090348

RESUMEN

To assess and compare the anti-microbial efficacy of 445 nm and 970 nm diode laser on mixed species biofilm of Aggregatibacter actinomycetemcomitans [A.a] and Porphyromonas gingivalis [P.g] cultured on machined pure titanium discs. A total of 65 machined pure titanium discs with no surface modifications with a 10-mm diameter and a 2-mm height were sterilized by autoclaving at 121 °C for 15 min and incubated with the commercially available bacterial strains ATCC(American Type Culture Collection- P.g 33277 and A.a 29522)mixture of Aggregatibacter actinomycetemcomitans(A.a) and Porphyromonas gingivalis(P.g).After a 2-week incubation period with the mixture of bacteria to develop a mixed species biofilm, the discs were divided into three groups: (1) no treatment (control), (2) 445 nm laser (test), (3) 970 nm laser (test). For each laser wavelength (445 and 970 nm), the discs were exposed to 1.0 W and 2.0 W in continuous wave mode for the times points of 15, 30, and 60 s. The antimicrobial efficacy was assessed by qPCR. A significant reduction in the levels of both species of bacteria was observed between control and the laser intervention groups. A higher efficacy for the 445 nm diode laser against Porphyromonas gingivalis and a similar efficacy against Aggregatibacter actinomycetemcomitans was observed as compared to the 970 nm group. 445 nm wavelength represents a potential and effective laser wavelength which can be used for the management of peri-implant infection. The present study findings also need to be further validated through clinical interventional trials.


Asunto(s)
Aggregatibacter actinomycetemcomitans , Biopelículas , Láseres de Semiconductores , Porphyromonas gingivalis , Titanio , Biopelículas/efectos de la radiación , Biopelículas/efectos de los fármacos , Porphyromonas gingivalis/fisiología , Láseres de Semiconductores/uso terapéutico , Titanio/química , Humanos , Técnicas In Vitro
14.
J Environ Manage ; 367: 121970, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39106792

RESUMEN

Photocatalysis has been proven to be an excellent technology for treating antibiotic wastewater, but the impact of each active species involved in the process on antibiotic degradation is still unclear. Therefore, the S-scheme heterojunction photocatalyst Ti3C2/g-C3N4/TiO2 was successfully synthesized using melamine and Ti3C2 as precursors by a one-step calcination method using mechanical stirring and ultrasound assistance. Its formation mechanism was studied in detail through multiple characterizations and work function calculations. The heterojunction photocatalyst not only enabled it to retain active species with strong oxidation and reduction abilities, but also significantly promoted the separation and transfer of photo-generated carriers, exhibiting an excellent degradation efficiency of 94.19 % for tetracycline (TC) within 120 min. Importantly, the priority attack sites, degradation pathways, degradation intermediates and their ecological toxicity of TC under the action of each single active species (·O2-, h+, ·OH) were first positively explored and evaluated through design experiments, Fukui function theory calculations, HPLC-MS, Escherichia coli toxicity experiments, and ECOSAR program. The results indicated that the preferred attack sites of ·O2- on TC were O20, C7, C11, O21, and N25 atoms with high f+ value. The toxicity of intermediates produced by ·O2- was also lower than those produced by h+ and ·OH.


Asunto(s)
Tetraciclina , Tetraciclina/química , Tetraciclina/toxicidad , Catálisis , Titanio/química , Oxidación-Reducción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Aguas Residuales/química , Escherichia coli/efectos de los fármacos , Antibacterianos/química , Antibacterianos/toxicidad
15.
Mikrochim Acta ; 191(9): 534, 2024 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136796

RESUMEN

Screen-printed carbon electrodes (SPCE) functionalized with MXene-based three-dimensional nanomaterials are reported for rapid determination of creatinine. Ti3C2TX MXene with in situ reduced AuNPs (MXene@AuNP) were used as a coreactant accelerator for efficient immobilization of enzymes. Creatinine could be oxidized by chitosan-embedded creatinine amidohydrolase, creatine amidinohydrolase, or sarcosine oxidase to generate H2O2, which could be electrochemically detected enhanced by Prussian blue (PB). The enzyme@CS/PB/MXene@AuNP/SPCE detected creatinine within the range 0.03-4.0 mM, with a limit of detection of 0.01 mM, with an average recovery of 96.8-103.7%. This indicates that the proposed biosensor is capable of detecting creatinine in a short amount of time (4 min) within a ± 5% percentage error, in contrast with the standard clinical colorimetric method. With this approach, reproducible and stable electrochemical responses could be achieved for determination of creatinine in serum, urine, or saliva. These results demonstrated its potential for deployment in resource-limited settings for early diagnosis and tracking the progression of chronic kidney disease (CKD).


Asunto(s)
Técnicas Biosensibles , Carbono , Creatinina , Técnicas Electroquímicas , Electrodos , Ferrocianuros , Oro , Peróxido de Hidrógeno , Límite de Detección , Nanopartículas del Metal , Sarcosina-Oxidasa , Ureohidrolasas , Creatinina/sangre , Creatinina/orina , Carbono/química , Humanos , Sarcosina-Oxidasa/química , Oro/química , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Ferrocianuros/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Peróxido de Hidrógeno/química , Nanopartículas del Metal/química , Ureohidrolasas/química , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Quitosano/química , Pruebas en el Punto de Atención , Amidohidrolasas , Titanio
16.
ACS Biomater Sci Eng ; 10(8): 5300-5312, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39087496

RESUMEN

The development of well-adherent, amorphous, and bioactive glass coatings for metallic implants remains a critical challenge in biomedical engineering. Traditional bioactive glasses are susceptible to crystallization and exhibit a thermal expansion mismatch with implant materials. This study introduces a novel approach to overcome these limitations by employing systematic Na2O substitution with CaO in borosilicate glasses. In-depth structural analysis (MD simulations, Raman spectroscopy, and NMR) reveals a denser network with smaller silicate rings, enhancing thermal stability, reducing thermal expansion, and influencing dissolution kinetics. This tailored composition exhibited optimal bioactivity (in vitro formation of bone-like apatite within 3 days) and a coefficient of thermal expansion closely matching Ti-6Al-4V, a widely used implant material. Furthermore, a consolidation process, meticulously designed with insights from crystallization kinetics and the viscosity-temperature relationship, yielded a crack-free, amorphous coating on Ti-6Al-4V substrates. This novel coating demonstrates excellent cytocompatibility and strong antibacterial action, suggesting superior clinical potential compared with existing technologies.


Asunto(s)
Materiales Biocompatibles Revestidos , Vidrio , Titanio , Vidrio/química , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Titanio/química , Prótesis e Implantes , Antibacterianos/química , Antibacterianos/farmacología , Ensayo de Materiales , Propiedades de Superficie , Aleaciones/química , Humanos
17.
Commun Biol ; 7(1): 962, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39122919

RESUMEN

With increases in life expectancy, the number of patients requiring joint replacement therapy and experiencing periprosthetic osteolysis, the most common complication leading to implant failure, is growing or underestimated. In this study, we found that osteolysis progression and osteoclast differentiation in the surface of the skull bone of adult mice were accompanied by significant expansion of lymphatic vessels within bones. Using recombinant VEGF-C protein to activate VEGFR3 and promote proliferation of lymphatic vessels in bone, we counteracted excessive differentiation of osteoclasts and osteolysis caused by titanium alloy particles or inflammatory cytokines LPS/TNF-α. However, this effect was not observed in aged mice because adipogenically differentiated mesenchymal stem cells (MSCs) inhibited the response of lymphatic endothelial cells to agonist proteins. The addition of the JAK inhibitor ruxolitinib restored the response of lymphatic vessels to external stimuli in aged mice to protect against osteolysis progression. These findings suggest that inhibiting SASP secretion by adipogenically differentiated MSCs while activating lymphatic vessels in bone offers a new method to prevent periprosthetic osteolysis during joint replacement follow-up.


Asunto(s)
Vasos Linfáticos , Células Madre Mesenquimatosas , Osteólisis , Animales , Osteólisis/prevención & control , Ratones , Vasos Linfáticos/efectos de los fármacos , Vasos Linfáticos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Envejecimiento , Ratones Endogámicos C57BL , Osteoclastos/metabolismo , Osteoclastos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Masculino , Fenotipo , Factor C de Crecimiento Endotelial Vascular/metabolismo , Factor C de Crecimiento Endotelial Vascular/genética , Cráneo/patología , Cráneo/efectos de los fármacos , Receptor 3 de Factores de Crecimiento Endotelial Vascular/metabolismo , Receptor 3 de Factores de Crecimiento Endotelial Vascular/genética , Titanio
18.
BMC Oral Health ; 24(1): 923, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39123150

RESUMEN

BACKGROUND: This study aimed to explore the effects of the titanium dioxide (TiO2) concentration and particle size in hydrogen peroxide (HP) on tooth bleaching effectiveness and enamel surface properties. METHODS: TiO2 at different concentrations and particle sizes was incorporated into 40% HP gel to form an HP/TiO2 gel. The specimens were randomly divided into 8 groups: C1P20: HP + 1% TiO2 (20 nm); C3P20: HP + 3% TiO2 (20 nm); C5P20: HP + 5% TiO2 (20 nm); C1P100: HP + 1% TiO2 (100 nm); C3P100: HP + 3% TiO2 (100 nm); C5P100: HP + 5% TiO2 (100 nm); C0: HP with LED; and C0-woL: HP without LED. Bleaching was conducted over 2 sessions, each lasting 40 min with a 7-day interval. The color differences (ΔE00), whiteness index for dentistry (WID), surface microhardness, roughness, microstructure, and composition were assessed. RESULTS: The concentration and particle size of TiO2 significantly affected ΔE00 and ΔWID values, with the C1P100 group showing the greatest ΔE00 values and C1P100, C3P100, and C5P100 groups showing the greatest ΔWID values (p < 0.05). No significant changes were observed in surface microhardness, roughness, microstructure or composition (p > 0.05). CONCLUSIONS: Incorporating 1% TiO2 with a particle size of 100 nm into HP constitutes an effective bleaching strategy to achieve desirable outcomes.


Asunto(s)
Geles , Peróxido de Hidrógeno , Propiedades de Superficie , Titanio , Blanqueadores Dentales , Blanqueamiento de Dientes , Titanio/química , Blanqueamiento de Dientes/métodos , Peróxido de Hidrógeno/uso terapéutico , Peróxido de Hidrógeno/administración & dosificación , Humanos , Tamaño de la Partícula , Esmalte Dental/efectos de los fármacos
19.
Sensors (Basel) ; 24(15)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39124105

RESUMEN

This paper presents a new biosensor design based on the Kretschmann configuration, for the detection of analytes at different refractive indices. Our studied design consists of a TiO2/SiO2 bi-layer sandwiched between a BK7 prism and a bimetallic layer of Ag/Au plasmonic materials, covered by a layer of black phosphorus placed below the analyte-containing detection medium. The different layers of our structure and analyte detection were optimized using the angular interrogation method. High performance was achieved, with a sensitivity of 240 deg/RIU and a quality factor of 34.7 RIU-1. This biosensor can detect analytes with a wide refractive index range between 1.330 and 1.347, such as glucose detection in urine samples using a refractive index variation of 10-3. This capability offers a wide range of applications for biomedical and biochemical detection and selectivity.


Asunto(s)
Técnicas Biosensibles , Glucosa , Fósforo , Titanio , Fósforo/química , Técnicas Biosensibles/métodos , Glucosa/análisis , Glucosa/química , Humanos , Titanio/química , Plata/química , Oro/química , Dióxido de Silicio/química , Refractometría
20.
Mikrochim Acta ; 191(9): 506, 2024 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-39097837

RESUMEN

Using a chemiluminescence reaction between luminol and H2O2 in basic solution, an ultrasensitive electrochemiluminescence (ECL) aptasensor was developed for the determination of tobramycin (TOB), as an aminoglycoside antibiotic. Ti3C2/Ni/Sm-LDH-based nanocomposite effectively catalyzes the oxidation of luminol and decomposition of H2O2, leading to the formation of different reactive oxygen species (ROSs), thus amplifying the ECL signal intensity of luminol, which can be used for the determination of TOB concentration. To evaluate the performance of the electrochemiluminescence aptasensor and synthesized nanocomposite, different methods such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analyses were performed. The considerable specific area, large number of active sites, and enhanced electron transfer reaction on this nanocomposite led to the development of an ECL aptasensor with high sensitivity and electrocatalytic activity. After optimizing the preparation method and analysis conditions, the aptasensor revealed a wide linear response ranging from 1.0 pM to 1.0 µM with a detection limit of 18 pM, displaying outstanding accuracy, specificity, and response stability. The developed ECL sensor was found to be applicable to the determination of TOB in human serum samples and is anticipated to possess excellent clinical potentials for detecting other antibiotics, as well.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Límite de Detección , Mediciones Luminiscentes , Nanocompuestos , Tobramicina , Nanocompuestos/química , Humanos , Técnicas Electroquímicas/métodos , Aptámeros de Nucleótidos/química , Mediciones Luminiscentes/métodos , Técnicas Biosensibles/métodos , Tobramicina/sangre , Tobramicina/análisis , Luminol/química , Antibacterianos/sangre , Antibacterianos/análisis , Peróxido de Hidrógeno/química , Níquel/química , Titanio/química
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