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1.
Adv Sci (Weinh) ; : e2401034, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647393

RESUMO

High-entropy oxides (HEOs) have garnered significant attention within the realm of rechargeable batteries owing to their distinctive advantages, which encompass diverse structural attributes, customizable compositions, entropy-driven stabilization effects, and remarkable superionic conductivity. Despite the brilliance of HEOs in energy conversion and storage applications, there is still lacking a comprehensive review for both entry-level and experienced researchers, which succinctly encapsulates the present status and the challenges inherent to HEOs, spanning structural features, intrinsic properties, prevalent synthetic methodologies, and diversified applications in rechargeable batteries. Within this review, the endeavor is to distill the structural characteristics, ionic conductivity, and entropy stabilization effects, explore the practical applications of HEOs in the realm of rechargeable batteries (lithium-ion, sodium-ion, and lithium-sulfur batteries), including anode and cathode materials, electrolytes, and electrocatalysts. The review seeks to furnish an overview of the evolving landscape of HEOs-based cell component materials, shedding light on the progress made and the hurdles encountered, as well as serving as the guidance for HEOs compositions design and optimization strategy to enhance the reversible structural stability, electrical properties, and electrochemical performance of rechargeable batteries in the realm of energy storage and conversion.

2.
Adv Mater ; : e2402184, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38458150

RESUMO

Efficient electrocatalysts are pivotal for advancing green energy conversion technologies. Organic electrocatalysts, as cost-effective alternatives to noble-metal benchmarks, have garnered attention. However, the understanding of the relationships between their properties and electrocatalytic activities remains ambiguous. Plenty of research articles regarding low-cost organic electrocatalysts started to gain momentum in 2010 and have been flourishing recently though, a review article for both entry-level and experienced researchers in this field is still lacking. This review underscores the urgent need to elucidate the structure-activity relationship and design suitable electrode structures, leveraging the unique features of organic electrocatalysts like controllability and compatibility for real-world applications. Organic electrocatalysts are classified into four groups: small molecules, oligomers, polymers, and frameworks, with specific structural and physicochemical properties serving as activity indicators. To unlock the full potential of organic electrocatalysts, five strategies are discussed: integrated structures, surface property modulation, membrane technologies, electrolyte affinity regulation, and addition of anticorrosion species, all aimed at enhancing charge efficiency, mass transfer, and long-term stability during electrocatalytic reactions. The review offers a comprehensive overview of the current state of organic electrocatalysts and their practical applications, bridging the understanding gap and paving the way for future developments of more efficient green energy conversion technologies.

3.
J Photochem Photobiol B ; 249: 112801, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37897855

RESUMO

Skin photoaging, resulting from prolonged exposure to sunlight, especially UVA rays, has been identified as a key contributor to age-related skin degeneration. However, the mechanism by which UVA radiation induces skin cell senescence has not been fully elucidated. In this investigation, bioinformatics technology was employed to identify SIRT6 as the core hub gene involved in the progression of skin photoaging. The study evinced that prolonged exposure of cutaneous fibroblasts to UVA radiation results in a marked reduction in the expression of SIRT6, both in vivo and in vitro. Knockdown of SIRT6 in skin fibroblasts resulted in the upregulation of genes associated with cellular aging, thereby exacerbating the effects of UVA radiation-induced photoaging. Conversely, overexpression of SIRT6 decreased the expression of cell aging-related genes, indicating that SIRT6 plays a role in the regulation of senescence in skin fibroblasts induced by UVA radiation. We proffer substantiation that overexpression of SIRT6 protects skin fibroblasts from UVA-induced oxidative stress by activating the NRF2/HO-1 signaling cascade. Moreover, SIRT6 overexpression also reduced UVA-induced type I collagen degradation by inhibiting NF-κB signaling cascade. In summary, our findings showed that overexpression of SIRT6 inhibits UVA-induced senescence phenotype and type I collagen degradation in skin fibroblasts by modulating the NRF2/HO-1 and NF-κB signaling pathways. And the regulation of these signaling pathways by SIRT6 may be achieved through its deacetylase activity. Therefore, SIRT6 is a novel and promising therapeutic target for skin aging related to age and UV.


Assuntos
Sirtuínas , Envelhecimento da Pele , Dermatopatias , Humanos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Fibroblastos/efeitos da radiação , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Sirtuínas/genética , Sirtuínas/metabolismo , Sirtuínas/farmacologia , Pele/efeitos da radiação , Raios Ultravioleta
4.
Phytother Res ; 37(11): 5193-5204, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37767805

RESUMO

Diabetic wounds are severe complications of diabetes mellitus (DM), which have difficulty in healing. Although diverse treatments have been used, the prognosis of diabetic wounds is not satisfactory; therefore, an effective therapy to accelerate diabetic wound healing is urgently needed. In our review, we summarized that resveratrol can promote diabetic wound healing by protecting against hyperglycemia, inflammation, oxidative stress, vascular pathology, infection, and peripheral neuropathy. To clarify it clearly, we highlighted its underlying mechanisms of protective effects of resveratrol against diabetic wounds, and high-quality studies are needed to firmly establish its clinical efficacy. Otherwise, with the development of material sciences, resveratrol can exert its therapeutic effectiveness efficiently; however, more high-quality studies are needed to confirm the clinical efficacy of resveratrol on diabetic wounds.


Assuntos
Diabetes Mellitus , Humanos , Resveratrol/farmacologia , Diabetes Mellitus/tratamento farmacológico , Cicatrização , Inflamação
5.
Int Wound J ; 20(8): 3088-3104, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37042039

RESUMO

Random skin flap transplantation is a commonly used technique. However, ischemia and ischemia-reperfusion injury always impair its therapeutic effectiveness through acclerating oxidative stress, apoptosis and suppressing angiogenesis. To survive, cells rely on mediating autophagy, DNA repair, immunoregulation to resist these cellular injuries. Thus, mediating autophagy may affect the survival of random skin flaps. The edaravone (EDA), a oxygen radicals scavenger, also possesses autophagy mediator potential, we investigated the effects of EDA on skin flap survival and its autophagy-related mechanisms. In vivo, mice were administered EDA or saline intraperitoneally for 7 days postoperatively. We found that EDA ameliorated the viability of random skin flaps, promoted autophagy and angiogenesis, attenuated apoptosis and oxidative stress. In vitro, mouse umbilical vascular endothelial cells (MUVECs) were administered EDA or 3-methyladenine (3-MA, an autophagy inhibitor) or rapacymin (Rapa, an autophagy activator) at the beginning of oxygen glucose deprivation (OGD). We found that EDA promoted cell viability, activated autophagy, enhanced angiogenesis, alleviated apoptosis and oxidative stress. On one hand, 3-MA reversed the effects of EDA on cell viability, oxidative stress and apoptosis via inhibiting autophagy. On the other hand, Rapa had the similar effects of EDA. Furthermore, EDA-induced autophagy was mediated through downregulating PI3K/Akt/mTOR signalling pathway. The findings showed that EDA ameliorated viability of random skin flaps by promoting angiogenesis, suppressing oxidative stress and apoptosis, which may be mediated by autophagic activation through downregulating PI3K/AKT/mTOR signalling pathway.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Camundongos , Animais , Edaravone/metabolismo , Edaravone/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Células Endoteliais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/farmacologia , Autofagia
6.
Inorg Chem ; 61(21): 8126-8134, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35381177

RESUMO

Contactless fluorescent thermometers are rapidly gaining popularity due to their sensitivity and flexibility. However, the development of sensitive and reliable non-rare-earth-containing fluorescent thermometers remains a significant challenge. Here, a new rare-earth-free, red-emitting phosphor, Li2MgHfO4:Mn4+, was developed for temperature sensing. An experimental analysis combined with density functional theory and crystal field calculations reveals that the sensitive temperature-dependent luminescence arises from nonradiative transitions induced by lattice vibration. Li2MgHfO4:Mn4+ also exhibits reliable recovery performance after 100 heating-cooling cycles due to the elimination of surface defects, which is rare but vital for practical application. This study puts forward a new design strategy for fluorescent thermometers and sheds light on the fundamental structure-property relationships that guide sensitive temperature-dependent luminescence. These considerations are crucial for developing next-generation fluorescence-based thermometers.

7.
Nutr J ; 17(1): 99, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30376840

RESUMO

BACKGROUND: Epidemiological studies regarding the association between dietary fiber intake and ovarian cancer risk are still inconsistent. We aimed to review the available evidence and conduct a dose-response meta-analysis to investigate the relationship between dietary fiber intake and ovarian cancer risk. METHODS: Relevant studies were identified by searching PubMed, EMBASE, and the Cochrane Library databases before August 2017. Studies that reported relative risk (RR) estimates with 95% confidence intervals (CIs) for the association between dietary fiber intake and risk of ovarian cancer were included. Random-effects models were used to combine the estimated effects extracted from individual study. RESULTS: Thirteen studies, with a total of 5777 ovarian cancer cases and 142,189 participants, met the inclusion criteria. The pooled multivariable RRs of ovarian cancer for the highest vs. the lowest category of dietary fiber intake was 0.78 (95% CI: 0.70, 0.88) with no evidence of heterogeneity (I2 = 4.20%, P = 0.40). Our dose-response analysis also showed a significant inverse association between dietary fiber intake and ovarian cancer risk (an increment of 10 g/day; combined RR: 0.88; 95% CI: 0.82, 0.93). There was no evidence for a nonlinear association (P for nonlinearity = 0.83). CONCLUSIONS: This meta-analysis suggests a significant inverse dose-response association between dietary fiber intake and ovarian cancer risk. Further studies with prospective design that take account of more potential confounders are warranted to confirm this association.


Assuntos
Fibras na Dieta/farmacologia , Neoplasias Ovarianas/prevenção & controle , Fibras na Dieta/administração & dosagem , Feminino , Humanos , Risco
8.
Mol Med Rep ; 15(6): 4077-4083, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28440420

RESUMO

In the present study, a novel polysaccharide, APS2-1, was isolated and purified from Astragalus membranaceus using DEAE-cellulose and Sephadex G-100 chromatography. The effect of APS2­1 on the promotion of wound healing was evaluated and its preliminary mechanism was investigated. In vitro experiments showed that APS2­1 was able to promote human skin fibroblast (HSF) propagation and accelerate cell cycle progression. For further examination, a scalded mice model was used to verify the effect of APS2­1 and investigate its mechanism of action. The analysis of biochemical parameters, including cyclin D1, inhibitor of nuclear factor κBα (IκBα), transforming growth factor (TGF)­ß1, basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) showed that APS2­1 inhibited the increase in cyclin D1 and IκBα, and promoted the expression of TGF­ß1, bFGF and EGF, which was further confirmed by histopathological observation. These results suggested that APS2­1 possessed high potential in wound healing and its mechanism was associated with inhibiting inflammation, accelerating cell cycle and promoting the secretion of repair factors.


Assuntos
Astragalus propinquus/química , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1/genética , Ciclina D1/metabolismo , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Fator de Crescimento Epidérmico/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Polissacarídeos/química , Polissacarídeos/isolamento & purificação
9.
J Plast Surg Hand Surg ; 49(6): 319-26, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26083309

RESUMO

BACKGROUND: Flap necrosis is generally regarded as the result of vasospasm, thrombosis, and infection. METHODS: To improve skin flap survival and lower the risk of side effects due to systemic drug delivery, we formulated and evaluated compound gels for transdermal application. The transdermal delivery of 1% azithromycin (AZM), 0.5% amlodipine besylate (AB), and 300 IU/g low molecular weight heparin (LMWH) in compound gels, singly or in combinations, was measured across rat skin in vitro. The effects of AB and LMWH on flap blood circulation was investigated using fluorescein angiography, by transdermally applying the gel onto the surface of an in vivo ischaemic flap rat model; concentrations of the drugs were detected in both blood plasma and flap tissue at assigned timepoints. Finally, infected ischaemic flaps were treated to evaluate their anti-inflammatory effects and sizes of flap survival area. RESULTS: Each drug efficiently penetrated the in vitro skin in a time-dependent manner. In the in vivo ischaemic flaps, AB or LMWH increased the blood supply. All gel formulations that included AZM were associated with less flap inflammation. The surviving areas after treatment with AZM+LMWH or AZM+AB were significantly larger than that treated with the AZM-only gel, and the largest surviving area was that treated with AZM+AB+LMWH. Gels containing no AZM could not decrease flap inflammation or increase flap survival. CONCLUSION: Transdermal application of a compound gel with AZM, AB, and LMWH combined is a promising method to prevent and treat flap infection, improve blood circulation, and increase the survival of infected ischaemic flaps.


Assuntos
Anlodipino/farmacologia , Azitromicina/farmacologia , Heparina de Baixo Peso Molecular/farmacologia , Retalhos Cirúrgicos/irrigação sanguínea , Infecção da Ferida Cirúrgica/tratamento farmacológico , Administração Cutânea , Animais , Distribuição de Qui-Quadrado , Quimioterapia Combinada , Géis , Sobrevivência de Enxerto , Humanos , Técnicas In Vitro , Isquemia/prevenção & controle , Ratos , Medição de Risco , Retalhos Cirúrgicos/microbiologia , Infecção da Ferida Cirúrgica/diagnóstico , Resultado do Tratamento
10.
Ann Plast Surg ; 71(2): 214-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23392258

RESUMO

The study aims to test the effect of transdermal application of azithromycin in the prevention of skin flap infection in experimental rats. The accumulative penetration quantities of azithromycin through excised rat skin and the azithromycin quantities in flap tissues from rats given 1%, 2%, and 3% azithromycin gels were assayed by UV spectrophotometer. Staphylococcus aureus and pathogenic Escherichia coli were inoculated to the underneath of the random ischemic rat flaps to induce bacterial infection. The azithromycin gels were applied on the flaps daily for 7 days. The survival areas of flaps were measured by planimetry. The accumulative penetration quantities of azithromycin and the azithromycin quantities in flap tissues increased in a time-dependent manner (P < 0.05). Azithromycin gels decreased the inflammatory reaction and enhanced the survival area of flaps (P < 0.05). We concluded that 1% azithromycin gel could penetrate into the flap tissues and significantly increase survival area of infected flaps.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Infecções por Escherichia coli/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Retalhos Cirúrgicos , Infecção da Ferida Cirúrgica/prevenção & controle , Administração Cutânea , Animais , Antibacterianos/farmacocinética , Azitromicina/farmacocinética , Relação Dose-Resposta a Droga , Esquema de Medicação , Infecções por Escherichia coli/tratamento farmacológico , Géis , Distribuição Aleatória , Ratos , Ratos Wistar , Espectrofotometria Ultravioleta , Infecções Estafilocócicas/tratamento farmacológico , Infecção da Ferida Cirúrgica/tratamento farmacológico , Resultado do Tratamento
11.
Artigo em Chinês | MEDLINE | ID: mdl-20540262

RESUMO

OBJECTIVE: Dexamethasone (DXM) can regulate the balance of neutrophil and cytokine and enhance the ischemia-reperfusion tolerance of the skin flap; amlodipine besylate (AB) can selectively expand the peripheral blood vessels and relieve the vascular smooth muscle spasm. To investigate the percutaneous penetration ability of DXM/AB compound gel and evaluate its effect on survival of ischemic skin flap. METHODS: Sodium carboxymethylcellulose was used to make blank gel, which was mixed in DXM, AB, azone (AZ), and propylene glycol (PG) respectively to make the compound gel containing 0.3%DXM/0.5%AB only (group D), the compound gel containing 3%AZ/2%PG, 3%AZ, and 2%PG (groups A, B, and C), the 0.3%DXM gel containing 3%AZ/2%PG (group E), the 0.5%AB gel containing 3%AZ/2%PG (group F). The accumulative penetration of DXM and AB in compound gel, 0.3%DXM gel, 0.5%AB gel through excised rat skin and its penetration within flap tissue were investigated by ultraviolet spectrophotometry. Fifty SD rats were selected to make 100 mm x 10 mm random flap at the back, and were randomly divided into 5 groups according to different gels which were used to treat flaps (n = 10): compound gel group (group A1), 0.3%DXM gel group (group B1), 0.5%AB gel group (group C1), blank gel group (group D1), and peritoneal injection of DXM (5 mg/kg) and AB (2 mg/kg) (group E1). The survival area of ischemic random skin flap was measured on the 7th day by planimetry. Twenty-four SD rats were selected to make 100 mm x 10 mm random flap at the back, and were randomly divided into 2 groups (n = 12). The accumulative penetration of DXM and AB within skin flap were also detected at 2 and 6 hours after application of 2 g of compound gel containing 3%AZ/2%PG (group A2) and peritoneal injection AB (2 mg/kg) / DXM (5 mg/kg) (group B2). RESULTS: The accumulative penetration of DXM and AB in compound gel were increased in time-dependent manner (P < 0.05), and it was the highest in group A, and was significantly higher than that in group B and group C (P < 0.01), but there was no significant difference when compared with group E or group F (P > 0.05). The accumulative penetration of DXM and AB in groups A, B, and C were significant higher than that in group D (P < 0.05). After 7 days, the survival area of flaps in groups A1, B1, C1, D1, and E1 were (695.0 +/- 4.6), (439.3 +/- 7.1), (477.5 +/- 14.5), (215.2 +/- 3.8), and (569.4 +/- 9.7) mm2, respectively; group A1 was significantly higher than other groups (P < 0.05). After 2 and 6 hours, the quantities of DXM and AB in skin flap of group A2 were significantly higher than that of group B2 (P < 0.05). CONCLUSION: In 0.3%DXM/0.5%AB compound gel, DXM and AB might penetrate into skin tissue, which could significantly increase the survival area of ischemic skin flap.


Assuntos
Anlodipino/farmacocinética , Dexametasona/farmacocinética , Sobrevivência de Enxerto/efeitos dos fármacos , Retalhos Cirúrgicos , Animais , Géis , Isquemia , Ratos , Ratos Sprague-Dawley , Reperfusão , Pele/irrigação sanguínea , Transplante de Pele
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