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1.
J Am Chem Soc ; 146(8): 5669-5677, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38350029

RESUMEN

Advanced atomic-level heterointerface engineering provides a promising method for the preparation of next-generation catalysts. Traditional carbon-based heterointerface catalytic performance rely heavily on the undetermined defects in complex and demanding preparation processes, rendering it impossible to control the catalytic performance. Here, we present a general method for the controlled growth of metal atom arrays on graphdiyne (GDY/IrCuOx), and we are surprised to find strong heterointerface strains during the growth. We successfully controlled the thickness of GDY to regulate the heterointerface metal atoms and achieved compressive strain at the interface. Experimental and density functional theory calculation results show that the unique incomplete charge transfer between GDY and metal atoms leads to the formation of strong interactions and significant heterointerface compressive strain between GDY and IrCuOx, which results in high oxidation performances with 1000 mA cm-2 at a low overpotential of 283 mV and long-term stability at large current densities in alkaline simulated seawater. We anticipate that this finding will contribute to construction of high-performance heterogeneous interface structures, leading to the development of new generation of GDY-based heterojunction catalysts in the field of catalysis for future promising performance.

2.
Small ; : e2401347, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716685

RESUMEN

A challenge facing the chlor-alkali process is the lack of electrocatalyst with high activity and selectivity for the efficient industrial production of chlorine. Herein the authors report a new electrocatalyst that can generate multi-interface structure by in situ growth of graphdiyne on the surface of cobalt oxides (GDY/Co3O4), which shows great potential in highly selective and efficient chlorine production. This result is due to the strong electron transfer and high density charge transport between GDY and Co3O4 and the interconversion of the mixed valence states of the Co atoms itself. These intrinsic characteristics efficiently enhance the conductivity of the catalyst, facilitate the reaction kinetics, and improve the overall catalytic selectivity and activity. Besides, the protective effect of the formed GDY layer is remarkable endowing the catalyst with excellent stability. The catalyst can selectively produce chlorine in low-concentration of NaCl aqueous solution at room temperature and pressure with the highest Faraday efficiency of 80.67% and an active chlorine yield rate of 184.40 mg h-1 cm-2, as well as superior long-term stability.

3.
J Am Chem Soc ; 145(32): 17588-17596, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37454391

RESUMEN

Organic dyes as non-noble metal photosensitizers have attracted increasing attention due to their environmental friendliness and sustainability but suffer from fast deactivation and low stability. Here, we reported a fruitful strategy by the confinement and stabilization of visible light-active signal unit organic dyes within the metal-organic frameworks (MOFs) and developed a series of heterogeneous photocatalysts dye@UiO-66s [dye = fluorescein (FL)/rhodamine B (RhB)/eosin Y (EY), UiO-66s = UiO-66, and Bim-UiO-66]. It has been demonstrated that the encapsulated dyes can effectively sensitize MOF hosts and dominate the band structures and photocatalytic activities of dye@UiO-66s regardless of the ligand functionalization of MOFs. Photocatalytic experiments showed that these dye@UiO-66s exhibit enhanced activities relative to free dyes and among them, FL@Bim-UiO-66 displays excellent efficiencies toward the green synthesis of new carbon-bridged annulations, [1,2,5]thiadiazole[3,4-g]benzoimidazoles in the yield of up to 98% at room temperature with outstanding stability and reusability. Furthermore, the intramolecular cyclization intermediate was captured and characterized by the single-crystal X-ray diffraction analysis.

4.
Small ; : e2309022, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38084449

RESUMEN

Seeking organic cathode materials with low cost and long cycle life that can be employed for large-scale energy storage remains a significant challenge. This work has synthesized an organic compound, triphenazino[2,3-b](1,4,5,8,9,12-hexaazatriphenylene) (TPHATP), with as high as 87.16% yield. This compound has a highly π-conjugated and rigid molecular structure, which is synthesized by capping hexaketocyclohexane with three molecules of 2,3-diaminophenazine derived from low-cost o-phenylenediamine, and is used as a cathode material for assembling aqueous rechargeable zinc ion batteries. Both experiments and DFT calculations demonstrate that the redox mechanism of TPHATP is predominantly governed by H+ storage. The Zn-intercalation product of nitride-type compound, is too unstable to form in water. Moreover, the TPHATP cathode exhibits a capacity of as high as 318.3 mAh g-1 at 0.1 A g-1 , and maintained a stable capacity of 111.9 mAh g-1 at a large current density of 10 A g-1 for 5000 cycles with only a decay of 0.000512% per cycle. This study provides new insights into understanding pyrazine as an active redox group and offers a potential affordable aqueous battery system for grid-scale energy storage.

5.
Inorg Chem ; 62(42): 17182-17190, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37815498

RESUMEN

Oxidation and removal of highly toxic sulfides and amines are particularly important for environmental and human security but remain challenging. Here, incorporating an excellent photosensitizer, donor-acceptor-donor (D-A-D)-type 4,4'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic (H2L), into metal-organic frameworks (MOFs) has been manifested to promote the charge separation, affording four three-dimensional (3D) MOFs (isostructural 1-Co/1-Zn with Co2/Zn2 units, and 2-Gd/2-Tb with Gd/Tb-cluster chains) as photocatalysts in the visible light-driven air-O2-mediated catalytic oxidation and removal of hazardous phenylsulfides and benzylamines. Impressively, structure-property correlation illustrated that the transition metal centers assembled in MOFs play an important role in the photocatalytic activity, and we can conclude that 1-Zn can be a robust heterogeneous catalyst possessing good light adsorption and fast charge separation in oxidation removal reactions of both benzylamines and phenylsulfides under visible light irradiation and room temperature with excellent activity/selectivity, stability, and reusability.

6.
Support Care Cancer ; 31(7): 375, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37273007

RESUMEN

BACKGROUND: Multikinase inhibitors (MKIs) treatment has been proven as a powerful strategy in cancer therapy. However, it is greatly hampered by its common adverse effect known as hand-foot skin reaction (HFSR), especially in patients with moderate-to-severe HFSR. OBJECTIVE: To investigate the clinical characteristics, histopathological features, treatment response, and bio-indicators of HFSR. METHODS: We retrospectively reviewed the medical records of 102 patients with moderate-to-severe HFSR resulting from MKIs therapy. RESULTS: The median time to development of moderate-to-severe HFSR was 18 days, which would be significantly affected by the type of MKIs and the history of HFSR. Notably, we found that HFSR was classified into three consecutive stages: erythematous lesion, yellow hyperkeratotic lesion with surrounding erythema, and hyperkeratotic lesion. Inflammation was observed in the first two stages of HFSR, but disappeared in the third stage; in contrast, the hyperkeratosis gradually became thicker from stage one to stage three. Moreover, topical medications were demonstrated as an effective therapy for HFSR, among which, the topical steroids and urea ointment treatment response rate was 37.14%, the Shouzu Ning Decoction (SND) treatment response rate was 65%, and the SND in combination with urea ointment treatment response rate was 75%, meanwhile, systemic therapies did not improve the therapeutic efficacy of topical medications alone. In addition, the serum levels of HMGB1 were found to be a potential indicator for tracking the healing process as well as predicting the prognosis of HFSR. CONCLUSION: This study revealed the potential factors affecting the development of HFSR, evaluated the therapeutic response towards different strategies for treating HFSR, and identified a potential prognostic indicator of HFSR.


Asunto(s)
Síndrome Mano-Pie , Inhibidores de Proteínas Quinasas , Humanos , Estudios Retrospectivos , Pomadas/uso terapéutico , Inhibidores de Proteínas Quinasas/efectos adversos , Resultado del Tratamiento , Pronóstico , Urea/uso terapéutico , Síndrome Mano-Pie/tratamiento farmacológico , Compuestos de Fenilurea/efectos adversos
7.
Lasers Med Sci ; 38(1): 280, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38030798

RESUMEN

This study aimed to investigate the effectiveness of erbium-doped yttrium garnet (Er:YAG) laser and GLUMA desensitizer for dentin hypersensitivity in teeth affected by Molar-Incisor Hypomineralization (MIH). One hundred twenty children were randomly allocated to four groups: the control (Co) group, the desensitizer (De) group, the laser (La) group, and the laser + desensitizer (La + De) group. Outcome measures included Visual Analogue Scale (VAS) and 14-item Oral Health Impact Profile (OHIP-14) evaluation. For mean VAS scores, a significant reduction was found over time in all groups. Co and De groups, Co and La groups, Co and La + De groups, De and La + De groups, and La and La + De groups differed significantly (p < 0.05). For mean scores in all dimensions of OHIP-14 after treatment 6 months, the La + De group was significantly lower (p < 0.001). The La + De groups and the La groups as well as the La + De groups and the De groups differed significantly in total OHIP, functional limitation, physical disability, and psychological disability (p < 0.05). Physical pain between the La + De groups and the La groups and handicap between the La + De groups and De groups differed significantly (p < 0.05). The mean values of each dimension differed significantly between the group Co and the La + De group (p < 0.0001). Combination therapy of Er:YAG laser and GLUMA desensitizer had greater desensitizing effects and oral health-related quality improvement of life, which might be an effective alternative treatment in dentin hypersensitivity in MIH children.


Asunto(s)
Sensibilidad de la Dentina , Terapia por Láser , Láseres de Estado Sólido , Hipomineralización Molar , Humanos , Niño , Láseres de Estado Sólido/uso terapéutico , Sensibilidad de la Dentina/radioterapia , Sensibilidad de la Dentina/tratamiento farmacológico , Dentina
8.
Carcinogenesis ; 43(3): 288-296, 2022 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-34888652

RESUMEN

Radioresistance is a major problem encountered in the treatment of non-small cell lung cancer (NSCLC). Aberrant microRNA (miRNA) expression contributes to multiple cancer-associated signaling pathways and profoundly influences effects of radiotherapy (RT) in cancers. MicroRNA-145-5p (miR-145) is recognized as a tumor suppresser in NSCLC. However, the roles of miR-145 during radiotherapy of NSCLC are largely unknown. The present study aimed to investigate the function and underlying mechanism of miR-145 in modulation of radiosensitivity in NSCLC. We generated radioresistant H460 and A549 subclones, named H460R and A549R, respectively, and found that irradiation (IR) could suppress the expression levels of miR-145 in radioresistant NSCLC cells. Furthermore, overexpression of miR-145 could sensitize radioresistant NSCLC cells to IR, whereas knockdown of miR-145 in NSCLC cells acted the converse manner. Mechanically, miR-145 was able to directly target 3'UTR of tropomodulin 3 (TMOD3) mRNA and decrease the expression of TMOD3 at the levels of mRNA and protein. Additionally, we confirmed that miR-145 could enhance the radiosensitivity of radioresistant NSCLC cells by targeting TMOD3 in vitro and in vivo, and could be used as a target in clinical treatment of NSCLC. Collectively, restoration of miR-145 expression increases the radiosensitivity of radioresistant NSCLC cells by suppression of TMOD3, and miR-145 can act as a new radiosensitizer for NSCLC therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Regiones no Traducidas 3'/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , MicroARNs/genética , MicroARNs/metabolismo , Tolerancia a Radiación/genética
9.
Small ; 18(13): e2107136, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35119196

RESUMEN

The intrinsic catalytic activity and active sites of the catalyst originate from the interface efficient charge transfer. A 2D graphdiyne (GDY) layer grown on the surface of zeolitic imidazolate framework nanocubes (ZIFNC@GDY) forms a novel structure of a perfect "donor-bridge-acceptor" interface, in which the ZIFNC and GDY act as electron donor and acceptor, respectively, linked by the sp-C-Co and sp-C-N bonds as bridges. Importantly, the as-prepared catalyst exhibits intrinsically high reactivity for ammonia production through the nitrate reduction reaction (NtRR) in neutral aqueous solutions at ambient pressures and temperatures. The NtRR performance of the as-prepared electrocatalyst is confirmed by the high NH3 yield rate (YNH3 ) of 0.40 ± 0.02 mmol h-1  cm-2 at potential of -0.745V versus RHE and Faradaic efficiency (FE) of 98.51 ± 0.75%, as well as the excellent stability. We show that such unique interfacial structures can accelerate the efficient electron transfers between the zeolitic imidazolate framework nanocubes (ZIFNC) core and GDY shell, enrich the electron density on the GDY surface, and thereby promote fast redox switching, creating more active sites, and improving the catalytic performances.


Asunto(s)
Amoníaco , Zeolitas , Catálisis , Oxidación-Reducción
10.
Inorg Chem ; 61(30): 11992-12002, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35866632

RESUMEN

Effective and rapid capture of heavy metal oxo-anions from wastewater is a fascinating research topic, but it remains a great challenge. Herein, benzimidazole and -CH3 groups were integrated into UiO-66 in succession via a step-by-step linker modification strategy that was performed by presynthesis modification (to give Bim-UiO-66) and subsequently by postsynthetic ionization (to give Bim-UiO-66-Me). The UiO-66s (UiO-66, Bim-UiO-66, and Bim-UiO-66-Me) were applied in the removal of heavy metal oxo-anions from water. The two benzimidazole derivatives (Bim-UiO-66 and Bim-UiO-66-Me) showed much better performance than UiO-66, as both the initial sorption rate and sorption capacities decreased in the order Bim-UiO-66-Me > Bim-UiO-66 > UiO-66. The maximum performances of Bim-UiO-66 are 5.1 and 1.7 times those of UiO-66. Remarkably, Bim-UiO-66-Me shows 7.5 and 3.0 times better performance than UiO-66. The higher absorptivity of cationic Bim-UiO-66-Me compared with UiO-66 can be attributed to a strong Coulombic interaction as well as an anion-π interaction and hydrogen bonding between the benzimidazolium functional group and heavy metal oxo-anions. The as-synthesized Bim-UiO-66-Me not only provides a promising candidate for application in removal of heavy metal oxo-anions in wastewater treatment but also opens up a new strategy for the design of high-performance adsorbents.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Adsorción , Aniones , Bencimidazoles , Cationes , Estructuras Metalorgánicas , Ácidos Ftálicos , Contaminantes Químicos del Agua/análisis
11.
Nanotechnology ; 34(8)2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36541541

RESUMEN

Carbon materials derived from metal-organic frameworks have attracted increasing attention as anodes for energy storage. In this study, Fe, Ni-doped ZIF-8 is carbonized at high temperature to obtain bimetallic Fe and Ni modified tension -relaxed carbon (FeNi@trC). Fe and Ni have opposite structural modification effects when the metal ions are doped into the ZIF-8 dodecahedron. The obtained carbon material maintains the regular dodecahedron morphology, which means the relaxation of tension and strong thermal stability during annealing. Moreover, the presence of nickel enhances the carbonization degree and electrochemical stability of FeNi@trC, while the calcination of the tensive ZIF-8 precursor offers more defect sites. The discharge capacities of FeNi@trC materials are stable at 182.9 mAh·g-1and 567.9 mAh·g-1for sodium-ion batterie (SIB) and lithium-ion batterie (LIB) at 0.05 A·g-1. Compared with the current density of 0.05 A·g-1, the discharge capacity of SIB and LIB attenuates by 29.4% and 55.9% at 1 A·g-1, respectively, and the FeNi@trC shows good performance stability in the following cycles.

12.
Acta Pharmacol Sin ; 42(7): 1111-1123, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33637947

RESUMEN

Ionizing radiation-induced intestinal injury is a catastrophic complication in patients receiving radiotherapy. Circulating exosomes from patients undergoing radiotherapy can mediate communication between cells and facilitate a variety of pathological processes in vivo, but its effects on ionizing radiation-induced intestinal damage are undetermined. In this study we investigated the roles of exosomes during total body irradiation (TBI)-induced intestinal injury in vivo and in vitro. We isolated exosomes from serum of donor mice 24 h after lethal dose (9 Gy) TBI (Exo-IR-24h), then intravenously injected the exosomes into receipt mice, and found that Exo-IR-24h injection not only exacerbated 9 Gy TBI-induced lethality and weight loss, but also promoted crypt-villus structural and functional injury of the small intestine in receipt mice. Moreover, Exo-IR-24h injection significantly enhanced the apoptosis and DNA damage of small intestine in receipt mice following TBI exposure. In murine intestinal epithelial MODE-K cells, treatment with Exo-IR-24h significantly promoted 4 Gy ionizing radiation-induced apoptosis, resulting in decreased cell vitality. We further demonstrated that Exo-IR-24h promoted the IR-induced injury in receipt mice partially through its DNA damage-promoting effects and attenuating Nrf2 antioxidant response in irradiated MODE-K cells. In addition, TBI-related miRNAs and their targets in the exosomes of mice were enriched functionally using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Finally, injection of GW4869 (an inhibitor of exosome biogenesis and release, 1.25 mg·kg-1·d-1, ip, for 5 consecutive days starting 3 days before radiation exposure) was able to rescue mice against 9 Gy TBI-induced lethality and intestinal damage. Collectively, this study reveals that exosomes are involved in TBI-induced intestinal injury in mice and provides a new target to protect patients against irradiation-induced intestinal injury during radiotherapy.


Asunto(s)
Exosomas/metabolismo , Enfermedades Intestinales/metabolismo , Mucosa Intestinal/metabolismo , Animales , Apoptosis/fisiología , Proliferación Celular/fisiología , Daño del ADN/fisiología , Rayos gamma , Enfermedades Intestinales/patología , Mucosa Intestinal/patología , Intestino Delgado/metabolismo , Intestino Delgado/patología , Masculino , Ratones Endogámicos BALB C , MicroARNs/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Traumatismos Experimentales por Radiación , Irradiación Corporal Total
13.
Zhongguo Zhong Yao Za Zhi ; 42(12): 2350-2354, 2017 Jun.
Artículo en Zh | MEDLINE | ID: mdl-28822192

RESUMEN

To investigate the effect of taurine(Tau) on ICAM-1, VCAM-1 by p-p38 pathway in bovine pulmonary artery endothelial cells(PAECs) and explore its mechanism of action. Generation 4-12 cells in primary cultures of PAECs were used in experiments and divided into five groups: control group, hypoxia(hyp) group, inhibitor(SB203580) group, treatment(Tau) group, and treatment+inhibitor(SB+Tau) group. The concentration of Tau:100 mmol•L⁻¹; p38 inhibitor SB203580: 20 µmol•L⁻¹; and the treatment time was 12 h. MTT assay was used to detect the inhibitory effect of different concentrations of Tau on PAECs. Western blot and Real-time PCR method were used to detect the p38 pathway proteins and ICAM-1, VCAM-1 expression levels. Immunofluorescence was used to investigate p38 nuclear displacement situation. The results of MTT showed that the inhibitory effect was gradually increased with increasing concentrations of Tau. Western blot and RT-PCR revealed that the protein and mRNA expression levels of ICAM-1, VCAM-1 were reduced by Tau. Western blot and immunofluorescence showed Tau can inhibit p38 activation. Tau may decrease the expression levels of VCAM-1 and ICAM-1 in endothelial cells induced by hypoxia through MAPK p38 pathway.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Molécula 1 de Adhesión Intercelular/metabolismo , Taurina/farmacología , Molécula 1 de Adhesión Celular Vascular/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Bovinos , Hipoxia de la Célula , Células Cultivadas
14.
BMC Oral Health ; 15: 148, 2015 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-26589825

RESUMEN

BACKGROUND: The objectives of this study were to investigated changes in OHRQoL among patients with different classifications of malocclusion during comprehensive orthodontic treatment. METHODS: Clinical data were collected from 81 patients (aged 15 to 24) who had undergone comprehensive orthodontic treatment. Participants were classified 3 groups: Class I (n = 35), II (n = 32) and III (n = 14) by Angle classification. OHRQoL was assessed using the Oral Health Impact Profile (OHIP-14). All subjects were examined and interviewed at baseline (T0), after alignment and leveling (T1), after correction of molar relationship and space closure (T2), after finishing (T3). Friedman 2-way analysis of variance (ANOVA) and Wilcoxon signed rank tests were used to compare the relative changes of OHRQoL among the different time points. A Bonferroni correction with P < 0.005 was used to declare significance. RESULTS: Significant reductions were observed in all seven OHIP-14 domains of three groups except for social disability (P > 0.005) in class I and class II, Handicap in class II and class III (P > 0.005). Class I patients showed significant changes for psychological disability and psychological discomfort domain at T1, functional limitation, physical pain at T2. Class III patients showed a significant benefit in all domains except physical pain and functional limitation. Class II patients showed significant changes in the physical pain, functional disability, and physical disability domains at T1. CONCLUSIONS: The impact of comprehensive orthodontic treatment on patients' OHRQoL do not follow the same pattern among patients with different malocclusion. Class II patients benefits the most from the stage of space closure, while class I patients benefits the first stage (alignment and leveling) of treatment in psychological disability and psychological discomfort domains.


Asunto(s)
Maloclusión/psicología , Salud Bucal , Ortodoncia Correctiva/psicología , Calidad de Vida , Actividades Cotidianas , Adolescente , Adulto , Atención Odontológica Integral , Femenino , Estudios de Seguimiento , Humanos , Masculino , Maloclusión/terapia , Maloclusión Clase I de Angle/psicología , Maloclusión Clase I de Angle/terapia , Maloclusión Clase II de Angle/psicología , Maloclusión Clase II de Angle/terapia , Maloclusión de Angle Clase III/psicología , Maloclusión de Angle Clase III/terapia , Cierre del Espacio Ortodóncico/psicología , Dimensión del Dolor/métodos , Habilidades Sociales , Estrés Psicológico/psicología , Técnicas de Movimiento Dental/psicología , Adulto Joven
15.
Front Physiol ; 14: 1272764, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37929208

RESUMEN

Dental pulp stem cells (DPSCs) are a type of mesenchymal stem cells that can differentiate into odontoblast-like cells and protect the pulp. The differentiation of DPSCs can be influenced by biomaterials or growth factors that activate different signaling pathways in vitro or in vivo. In this review, we summarized six major pathways involved in the odontogenic differentiation of DPSCs, Wnt signaling pathways, Smad signaling pathways, MAPK signaling pathways, NF-kB signaling pathways, PI3K/AKT/mTOR signaling pathways, and Notch signaling pathways. Various factors can influence the odontogenic differentiation of DPSCs through one or more signaling pathways. By understanding the interactions between these signaling pathways, we can expand our knowledge of the mechanisms underlying the regeneration of the pulp-dentin complex.

16.
Drug Des Devel Ther ; 17: 167-180, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36712950

RESUMEN

Purpose: To evaluate the effects of dentin pretreatment with chitosan-loaded oleuropein nanoparticles (CONPs) on the durability of resin-dentin bonding interfaces. Methods: Eighty freshly extracted non-carious human third molars were randomly divided into four groups (n = 20 each): a de-ionized water (DW) group, a chitosan (CS) group, a chlorhexidine (CHX) group and a CONP group. The dentin in the DW, CS, CHX, and CONP groups were pretreated with de-ionized water, 1.0 mg/L CS solution, 2% chlorhexidine solution, and CONP suspension (prepared with 100 mg/L oleuropein), respectively, followed by the universal adhesive and resin composites. The bonded teeth of each group were randomly divided into two subgroups: an immediate subgroup and an aged subgroup. The bonded teeth of each group were then cut into the bonded beams. We measured their microtensile bond strength (µTBS), observed the characteristics of bonding interface by atomic force microscope, calculated the percentage of silver particles in a selected area for interfacial nanoleakage analysis, and evaluated the endogenous gelatinase activity within the bonding interface for in-situ zymogram analysis. Data were analyzed with two-way ANOVA and LSD multiple comparison test (P < 0.05). Results: Regardless of after 24 h or after thermocycling, CONP exhibited better µTBS (P < 0.05) than the other three groups except that there was not a statistical significance (P > 0.05) in the CONP and CHX groups after 24 h. Besides, the CONP group presented significantly higher modulus of elasticity in the hybrid layers (P < 0.05), lower expression of nanoleakage (P < 0.05), and better inhibitory effect of matrix metalloproteinases than the other three groups before and after thermocycling. Conclusion: Altogether, the CONPs had the potential to act as a dentin primer, which could effectively improve the dentin-resin binding durability.


Asunto(s)
Quitosano , Clorhexidina , Humanos , Anciano , Clorhexidina/farmacología , Clorhexidina/análisis , Clorhexidina/química , Quitosano/farmacología , Dentina/química , Recubrimientos Dentinarios/análisis , Recubrimientos Dentinarios/química , Recubrimientos Dentinarios/farmacología , Resistencia a la Tracción , Ensayo de Materiales , Agua/química
17.
Technol Health Care ; 31(2): 647-659, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36093647

RESUMEN

BACKGROUND: The integrity and stability of collagen are crucial for the dentin structure and bonding strength at dentin-resin interface. Natural plant-derived polypehenols have been used as collagen crosslinkers. OBJECTIVE: The aims of the study were to develop novel chitosan oleuropein nanoparticles (CS-OL-NPs), and to investigate the CS-OL-NPs treated dentin's the resistance to enzymatic degradation and mechanic property. METHODS: CS-OL-NPs were developed using the ionotropic gelation method. Release and biocompatibility of the CS-OL-NPs were tested. Twenty demineralized dentin collage specimens were randomized into four interventions groups: A, Deionized Water (DW); B, 5% glutaraldehyde solution (GA); C, 1 mg/ml chitosan (CS); and D, 100 mg/L CS-OL-NPs. After 1-min interventions, dentin matrix were evaluated by the micro-Raman spectroscopy for the modulus of elasticity test. Collagen degradation was assessed using hydroxyproline (HYP) assay. RESULTS: CS-OL-NPs were spherical core-shape with a size of 161.29 ± 8.19 nm and Zeta potential of 19.53 ± 0.26 mV. After a burst release of oleuropein in the initial 6 h, there was a long-lasting steady slow release. CS-OL-NPs showed a good biocompatibility for the hPDLSCs. The modulus of elasticity in the crosslinked groups were significantly higher than that in the control group (P< 0.05 for all). The specimens treated with CS-OL-NP showed a greater modulus of elasticity than those treated with GA and CS (P< 0.05 for both). The release of HYP in the crosslinked group was significantly lower than that in the non-crosslinked groups (P< 0.05 for all). CONCLUSION: CS-OL-NPs enhanced the dentin mechanical property and resistance to biodegradation, with biocompatibility and potential for clinical application.


Asunto(s)
Quitosano , Nanopartículas , Humanos , Quitosano/farmacología , Colágeno/farmacología , Dentina/química , Nanopartículas/química
18.
Chem Commun (Camb) ; 59(49): 7611-7614, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37254822

RESUMEN

The development of new catalysts with high selectivity and efficiency for the electrocatalytic nitrate reduction reaction (NtRR) to produce ammonia (NH3) at room temperature and ambient pressure is still a challenge. Herein, we report a simple in situ growth method for the controlled synthesis of a GDY-MnOx heterointerface by selectively anchoring and growing MnOx on GDY surfaces. Experimental results show that the incomplete charge-transfer between GDY and Mn atoms at the interface structures largely increases the number of active sites, improves the electrical conductivity, and therefore results in excellent electrocatalytic performance for NH3 synthesis with a maximum FE of 95.4%, an NH3 yield rate of 463.4 µmol h-1 cm-2 and high long-term stability in 0.1 M KOH + 0.1 M NO3- aqueous electrolytes at room temperature and ambient pressure.


Asunto(s)
Amoníaco , Nitratos , Conductividad Eléctrica
19.
ChemSusChem ; 16(23): e202300861, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-37578808

RESUMEN

Graphdiyne, a sp/sp2 -cohybridized two-dimensional all- carbon material, has many unique and fascinating properties of alkyne-rich structures, large π conjugated system, uniform pores, specific unevenly-distributed surface charge, and incomplete charge transfer properties provide promising potential in practical applications including catalysis, energy conversion and storage, intelligent devices, life science, photoelectric, etc. These superior advantages have made graphdiyne one of the hottest research frontiers of chemistry and materials science and produced a series of original and innovative research results in the fundamental and applied research of carbon materials. In recent years, considerable advances have been made toward the development of graphdiyne-based multiscale catalysts for nitrogen fixation and ammonia synthesis at room temperatures and ambient pressures. This review aims to provide a comprehensive update in regard to the synthesis of graphdiyne-based multiscale catalysts and their applications in the synthesis of ammonia. The unique features of graphdiyne are highlighted throughout the review. Finally, it concludes with the discussion of challenges and future perspectives relating to graphdiyne.

20.
ACS Nano ; 17(14): 14079-14098, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37399352

RESUMEN

Ionizing radiation (IR) is associated with the occurrence of enteritis, and protecting the whole intestine from radiation-induced gut injury remains an unmet clinical need. Circulating extracellular vesicles (EVs) are proven to be vital factors in the establishment of tissue and cell microenvironments. In this study, we aimed to investigate a radioprotective strategy mediated by small EVs (exosomes) in the context of irradiation-induced intestinal injury. We found that exosomes derived from donor mice exposed to total body irradiation (TBI) could protect recipient mice against TBI-induced lethality and alleviate radiation-induced gastrointestinal (GI) tract toxicity. To enhance the protective effect of EVs, profilings of mouse and human exosomal microRNAs (miRNAs) were performed to identify the functional molecule in exosomes. We found that miRNA-142-5p was highly expressed in exosomes from both donor mice exposed to TBI and patients after radiotherapy (RT). Moreover, miR-142 protected intestinal epithelial cells from irradiation-induced apoptosis and death and mediated EV protection against radiation enteritis by ameliorating the intestinal microenvironment. Then, biomodification of EVs was accomplished via enhancing miR-142 expression and intestinal specificity of exosomes, and thus improved EV-mediated protection from radiation enteritis. Our findings provide an effective approach for protecting against GI syndrome in people exposed to irradiation.


Asunto(s)
Enteritis , Exosomas , Vesículas Extracelulares , MicroARNs , Humanos , Vesículas Extracelulares/metabolismo , MicroARNs/metabolismo , Exosomas/metabolismo , Enteritis/metabolismo
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