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Aim: Lysosomal pH changes are associated with drug resistance, cell growth and invasion of tumors, but effective and specific real-time monitoring of lysosomal pH compounds for cancer therapy is lacking. Materials & methods: Here, based on the covalent linkage of the anticancer drug palbociclib and fluorescent dye fluorescein isothiocyanate (FITC), we designed and developed a novel palbociclib-derived multifunctional molecule (Pal-FITC) for lysosomal targeting and diagnostic therapeutic integration. Results & discussion: Pal-FITC fluoresces is 20-fold stronger than that of FITC and shows a linear response in the pH range of 4.0-8.2 (R2 = 0.9901). Pal-FITC blocks cells in G1 phase via Cyclin D-CDK4/6-Rb. Conclusion: Our study provides new strategies for tumor-targeted imaging and personalized therapy.
Based on the covalent linkage of the anticancer drug and the fluorescent dye, we designed and developed a novel palbociclib-derived multifunctional molecule (Pal-FITC) for lysosomal targeting and diagnostic therapeutic integration. Pal-FITC responded linearly in the pH range of 4.08.2. In addition, Pal-FITC was able to effectively treat lung cancer without toxic side effects on normal cells. It has a significant cell cycle blocking phenomenon and blocks G1 phase cells via Cyclin D-CDK4/6-Rb. Our study provides a new strategy for tumor-targeted imaging and personalized therapy.
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Antineoplásicos , Lisossomos , Piperazinas , Piridinas , Humanos , Piridinas/química , Piridinas/farmacologia , Lisossomos/metabolismo , Piperazinas/química , Piperazinas/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Corantes Fluorescentes/síntese química , Fluoresceína-5-Isotiocianato/química , Proliferação de Células/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/metabolismo , Estrutura MolecularRESUMO
Background: Humans are frequently exposed to N-nitrosamines through various sources, including diet, cigarette smoking, contaminated water, the atmosphere, and endogenous nitrosation. Exposure to these carcinogens may also contribute to the gender-specific incidence of liver cancer, which is significantly higher in males than in females, possibly due to the influence of endogenous hormones such as testosterone. However, the effect of testosterone on N-nitrosamine-induced liver cancer and its underlying mechanism remains unclear. Purpose: To investigate the effect of testosterone on the development of liver cancer induced by N-nitrosamines exposure. Patients and Methods: Histopathological and immunohistochemical staining techniques were employed to analyze the expression levels and nuclear localizations of key signaling molecules, including androgen receptor (AR), ß-catenin, and HMGB1, in both tumor and non-tumor regions of liver samples obtained from human patients and mice. Results: The findings demonstrated a strong correlation between AR and ß-catenin in the nuclear region of tumor areas. AR also showed a significant correlation with HMGB1 in the cytoplasmic region of non-tumor areas in both human and mice samples. The study further analyzed the expression levels and patterns of these three proteins during the progression of liver tumors. Conclusion: This study confirms that AR has the ability to modulate the expression levels and patterns of ß-catenin and HMGB1 in vivo, thereby exacerbating the progression of liver cancer induced by environmental N-nitrosamines exposure. Importantly, the effect of testosterone on the formation of liver cancer induced by environmental N-nitrosamine exposure intensifies this progression. These findings have important implications for drug safety in clinical practice and emphasize the significance of reducing N-nitrosamines exposure through conscious choices regarding diet and lifestyle to ensure environmental safety.
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Traditional eye drops are administered via topical instillation. However, frequent dosing is needed due to their relatively rapid precorneal removal and low ocular bioavailability. To address these issues, stearoyl L-carnitine-modified nanoemulsions (SC-NEs) were fabricated. The physicochemical properties of SC-NEs in terms of size, morphology, zeta potential, encapsulation efficiency, and in vitro drug release behavior were characterized. The cellular uptake and mechanisms of SC-NEs were comprehensively studied in human corneal epithelial cells and the stearoyl L-carnitine ratio in SC-NEs was optimized. The optimized SC-NEs could target the novel organic cation/carnitine transporter 2 (OCTN2) and amino acid transporter B (0 +) (ATB0,+) on the corneal epithelium, which led to superior corneal permeation, ocular surface retention ability, ocular bioavailability. Furthermore, SC-NEs showed excellent in vivo anti-inflammatory efficacy in a rabbit model of endotoxin-induced uveitis. The ocular safety test indicated that the SC-NEs were biocompatible. In general, the current study demonstrated that OCTN2 and ATB0,+-targeted nanoemulsions were promising ophthalmologic drug delivery systems that can improve ocular drug bioavailability and boost the therapeutic effects of drugs for eye diseases.
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Sistemas de Liberação de Medicamentos , Células Epiteliais , Animais , Humanos , Coelhos , Membro 5 da Família 22 de Carreadores de Soluto/metabolismo , Transporte Biológico , Células Epiteliais/metabolismo , Carnitina/metabolismo , Carnitina/farmacologiaRESUMO
Developing high-performance bifunctional electrocatalysts towards the hydrogen evolution reaction/oxygen evolution reaction (HER/OER) holds great significance for efficient water splitting. This work presents a two-stage metal-organic thermal evaporation strategy for the fabrication of Ru-based catalysts (Ru/NF) through growing ruthenium (Ru)/ruthenium dioxide (RuO2) nanoparticles (NPs) on nickel foam (NF). The optimal Ru/NF shows remarkable performance in both the HER (26.1 mV) and the OER (235.4 mV) at 10 mA cm-2 in an alkaline medium. The superior OER performance can be attributed to the synergistic interaction between Ru and RuO2, facilitating fast alkaline water splitting. Density functional theory studies reveal that the resulting Ru/RuO2 with the (110) crystal surface reinforces the adsorption of oxygen on RuO2, while metallic Ru improves water dissociation in alkaline electrolytes. Besides, Ru/NF requires only 1.50 V at 10 mA cm-2 for overall water splitting, surpassing 20 wt% Pt/C/NF||RuO2/NF. This work demonstrates the promising potential of a thermal evaporation approach for designing stable Ru-based nanomaterials loaded onto conductive substrates for high performance overall water splitting.
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BACKGROUND: To investigate the inhibitory effect of a hyaluronic acid hydrogel loaded with hydroxycamptothecin (HCPT) on scar formation after filtration surgery in a rabbit model. METHODS: Scleral fibroblasts were isolated and extracted from rabbits' eyes. After treatment with different concentrations of HCPT, cytotoxicity was detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and proliferation and extent of apoptosis were analysed using flow cytometry. Hydrogels loaded with different dosages of HCPT were prepared and placed under the scleral flap after the filtration surgery. One day, one week, and two weeks after surgery, follicular, conjunctival, corneal, and anterior chamber inflammation and iris and lens changes were observed. RESULTS: In vitro, compared with cells not treated with HCPT, cells treated with HCPT had decreased survival rate and proliferation, and the apoptosis level increased with increasing HCPT concentrations (p < 0.05). In vivo, the flattening time of filtering blebs in the three groups treated with different dosages of HCPT hydrogel was delayed. The degrees of oedema, inflammation, and bleeding were similar to those observed in the control group. The HCPT hydrogel effectively downregulated the expression of collagen 1 and 3 and tissue inhibitor of metalloproteinase 2 and upregulated the expression of matrix metalloproteinase 2 in a dose-dependent manner. CONCLUSIONS: HCPT significantly inhibited the growth of rabbits' scleral fibroblasts and effectively inhibited scar formation after filtering surgery by accelerating the degradation of extracellular matrix deposition.
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Cicatriz , Metaloproteinase 2 da Matriz , Animais , Coelhos , Cicatriz/tratamento farmacológico , Cicatriz/prevenção & controle , Cicatriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Camptotecina/farmacologia , Apoptose , Fibroblastos/metabolismo , Proliferação de CélulasRESUMO
Exosomes are responsible for cell-to-cell communication and serves as a valuable drug delivery vehicle. However, exosome heterogeneity, non-standardized isolation methods and proteomics/bioinformatics approaches limit its clinical applications. To better understand exosome heterogeneity, biological function and molecular mechanism of its biogenesis, secretion and uptake, techniques in proteomics or bioinformatics were applied to investigate human embryonic kidney cell (293T cell line)-derived exosome proteome and enable an integrative comparison of exosomal proteins and protein-protein interaction (PPI) networks of eleven exosome proteomes extracted from diverse human samples, including 293T (two datasets), dermal fibroblast, mesenchymal stem cell, thymic epithelial primary cell, breast cancer cell line (MDA-MB-231), patient neuroblastoma cell, plasma, saliva, serum and urine. Mapping of exosome biogenesis/secretion/uptake-related proteins onto exosome proteomes highlights exosomal origin-specific routes of exosome biogenesis/secretion/uptake and exosome-dependent intercellular communication. The finding provides insight into comparative exosome proteomes and its biogenesis, secretion and uptake, and potentially contributes to clinical applications.
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Exossomos , Proteoma , Humanos , Proteoma/metabolismo , Linhagem Celular , Células Epiteliais/metabolismoRESUMO
Introduction: Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer kind. According to recent research, a fatty liver increases the risk of hepatocellular cancer. Nevertheless, the AMPK signaling pathway is crucial. In addition, 5'-AMP-activated protein kinase (AMPK) is strongly linked to alterations in the tumor microenvironment, such as inflammation, hypoxia, and aging. The objective of this study is to evaluate the impact of the AMPK signaling pathway on the progression of fatty liver to HCC. Methods: In this study, we established a mouse liver cancer model using high-fat diets and nano-nitrosamines (nano-DEN). In addition, we employed a transcriptomic technique to identify all mRNAs detected in liver samples at the 25th weekexpression of proteins linked with the LKB1-AMPK-mTOR signaling pathway, inflammation, aging, and hypoxia was studied in microarrays of liver cancer tissues from mice and humans. These proteins included p-AMPK, LKB1, mTOR, COX-2, ß-catenin, HMGB1, p16, and HIF-1α. Results: Data were collected at different times in the liver as well as in cancerous and paracancerous regions and analyzed by a multispectral imaging system. The results showed that most of the genes in the AMPK signaling pathway were downregulated. Prakk1 expression was upregulated compared to control group but downregulated in the cancerous regions compared to the paracancerous regions. Stk11 expression was downregulated in the cancerous regions. Mtor expression was upregulated in the cancerous regions. During liver cancer formation, deletion of LKB1 in the LKB1-AMPK-mTOR signaling pathway reduces phosphorylation of AMPK. It contributed to the upregulation of mTOR, which further led to the upregulation of HIF1α. In addition, the expression of ß-catenin, COX-2, and HMGB1 were upregulated, as well as the expression of p16 was downregulated. Discussion: These findings suggest that changes in the AMPK signaling pathway exacerbate the deterioration of disrupted energy metabolism, chronic inflammation, hypoxia, and cellular aging in the tumor microenvironment, promoting the development of fatty liver into liver cancer.
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Cancer is one of the most serious diseases threatening human health, so it is particularly important to develop effective tumor-targeting drugs. As the first CDK4/6 inhibitor, palbociclib effectively inhibits tumor proliferation by blocking the cell cycle to the G1 phase. 10-HCPT is a Topo I inhibitor; however, its clinical application has been greatly limited due to its high toxicity. Based on the successful development of double target inhibitors, three novel palbociclib derivatives (HP-1, HP-2, and HP-3) were designed and synthesized from Palbociclib and 10-HCPT, and their biological activities were investigated. At first, the possible binding sites of the three compounds to Topo I and CDK4/6 were predicted by molecular docking. Then, we evaluated the anti-proliferative effects of the three palbociclib derivatives. In general, human lung cancer cells were more sensitive to HP-1, HP-2, and HP-3, especially NCI-H460. In addition, cell cycle arrest and apoptosis induction were investigated by flow cytometry. The three palbociclib derivatives, especially HP-1, had obvious cell cycle arrest phenomenon on NCI-H460 cells and induced apoptosis of NCI-H460 cells significantly. In the end, it was proved that these three drugs had obvious cyclin-dependent kinase inhibitory activities. In short, all the data showed that HP-1, HP-2, and HP-3 could play anti-cancer roles by acting on dual targets and had the characteristics of high efficiencies and low toxicities, which opened up a new idea for the study of palbociclib derivatives.
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PURPOSE: To explore the effect of doxycycline on vasculogenic mimicry (VM) formation and the potential mechanism in human pterygium fibroblasts in order to find novel targets for pterygium therapy. METHODS: First, we demonstrate the existence of VM in 73 pterygium specimens by CD31 and periodic acid Schiff (PAS) dual staining. Then we used cell counting kit-8, clone formation assay and flow cytometry to prove the inhibitory effect of doxycycline on cell proliferation and apoptosis. The VM formation was evaluated through wound healing assay, cell transwell assay and three-dimensional cell culture combined with PAS staining. Finally, we used Western blot to testify the correlation of the VM and the factors in protein level preliminarily. RESULTS: Our results showed that VM existed in human pterygium specimens exactly. Otherwise, in human pterygium fibroblasts, doxycycline induced a dose-dependent inhibitory effect on cell proliferation and apoptosis induction. Besides, doxycycline significantly suppressed vasculogenic mimicry tube formation, cell migration and invasion. Furthermore, doxycycline impaired the expression of MMP-9, MMP-2 and VEGF which may related to pterygium VM formation. CONCLUSIONS: Doxycycline decelerated pterygium progression might be through inhibiting VM formation according to the downregulation of MMP-9, MMP-2 and VEGF, which may provide the basis of further studies involving doxycycline for pterygium treatment.
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Metaloproteinase 2 da Matriz , Pterígio , Linhagem Celular Tumoral , Túnica Conjuntiva/anormalidades , Doxiciclina/farmacologia , Fibroblastos/metabolismo , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neovascularização Patológica/metabolismo , Ácido Periódico , Pterígio/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Exploring highly active and inexpensive electrocatalysts for oxygen evolution reaction (OER) is considered to be one of the preconditions for the development of energy and environment-related technologies. Nickel-based layered double hydroxides (LDHs) are extensively-studied OER electrocatalysts, but they still require relatively high overpotentials to achieve threshold current densities. In this work, iron-doped nickel-vanadium hydroxide microspheres (Fe-doped NiV HMS) were synthesized by doping iron ions into the NiV HMS through a facile cation-exchange method. The Fe-doped NiV HMS are hollow hierarchical structure stacked by high-density perpendicularly-lying nanosheets, which provide enough space for electrolyte penetration and diffusion. Owing to optimized composition and hollow hierarchical structure, the Fe-doped NiV HMS exhibits excellent electrocatalytic performance, which possessed a very low running overpotential (255 mV at 10 mA cm-2) and a smallest Tafel slope (56 mV dec-1) compared with hierarchical NiV HMS toward OER. Electrochemical results and density functional theory (DFT) manifest that Fe doping could regulate the electronic structure of NiV HMS, thus improving its electrical conductivity and electron transfer rate, and thus enhancing its catalytic activity. This research provides a convenient way to prepare Ni-based hydroxides as promising OER catalysts.
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Urinary tract infections (UTI) are recognized as one of the most common infectious diseases worldwide, and uropathogenic Escherichia coli (UPEC) is the main causative agent of UTI. Dendrobium officinale polysaccharides (DOPs), the main effective ingredient in Dendrobium officinale, have been reported to possess an anti-inflammatory role. Whether DOPs can attenuate the inflammatory injury (pyroptosis) induced by UPEC remains unknown. The present study aimed to assess the protective effect and potential mechanism of DOPs in UPEC-induced pyroptosis. Cell viability of THP-1 differentiated macrophage cells with DOPs was determined using MTT assay. Pyroptosis by UPEC in macrophage cells with or not DOPs pre-treatment was evaluated with flow cytometry analysis, lactate dehydrogenase (LDH) assay, and proinflammatory cytokines secretion. Expression level of key proteins in the NLRP3/Caspase-1/GSDMD pyroptotic pathway was analyzed with western blot. Furthermore the effect of DOPs on ROS activation was investigated. Results indicated that DOPs attenuated UPEC-induced cell damage in macrophage cells, inhibited the activation of NLRP3 mediated inflammasome, subsequently decreased induction and activation of caspase-1/GSDMD, and reduced the secretion of pro-inflammatory cytokine (IL-1ß et al.). Moreover, pretreatment with DOPs significantly reduces ROS production, an important/putative pyroptosis stimulus signal. These results suggested that DOPs successfully mitigate UPEC-promoted pyroptosis in macrophage cells. The protective effects of DOPs are associated with the inhibition of the NLRP3/Caspase-1/GSDMD pathway and ROS signal activation.
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Dendrobium , Macrófagos , Polissacarídeos , Piroptose , Escherichia coli Uropatogênica , Caspase 1/metabolismo , Dendrobium/química , Humanos , Inflamassomos/metabolismo , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Polissacarídeos/metabolismo , Polissacarídeos/farmacologia , Piroptose/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Escherichia coli Uropatogênica/metabolismo , Escherichia coli Uropatogênica/patogenicidadeRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Gynura procumbens (Lour.) Merr, (Family Asteraceae), which serves as both medicine and food in traditional ethnic medicine, has the effects of diminishing inflammation, relieving cough, reducing blood glucose and lipids levels, mitigating hepatotoxicity, and can be used for liver cancer prevention and treatment. AIM OF THE STUDY: To explore how the ethanol extract of Gynura procumbens stems (EEGS) can effectively intervene in the tumor microenvironment, it is necessary to study the mechanism of EEGS on the chemical toxicant nanodiethylnitrosamine (nanoDEN) that induces liver cancer. MATERIALS AND METHODS: EEGS contains large quantities of caffeoylquinic acid (CAC) and non-caffeoylquinic acid (n-CAC), which can be separated by high-performance liquid chromatography. The liver cancer model that was induced by the chemical toxin, nanoDEN, was used to clarify the effective mechanism for tumor intervention of the EEGS and its active ingredients. RESULTS: (1) after interventions with the four drugs on liver cancer, the tumor nodules were obviously reduced and inflammation levels improved. (2) The immunohistochemical staining results showed that both the EEGS and its active ingredients could significantly reverse the abnormal changes in inflammation, proliferation, aging and hypoxia-related proteins in mouse liver tissues that were caused by nanoDEN. (3) Real-time PCR results showed that compared with the nanoDEN group, the expression levels of inflammatory, fatty, and fibrosis-related factors in each group after drug intervention were decreased. (4) The transmission electron microscopy measurements showed that the EEGS significantly reversed the nanostructure changes in hepatocytes that were induced by nanoDEN. CONCLUSION: The EEGS component of Gynura procumbens is effective in preventing and treating liver cancer by interfering with the inflammatory microenvironment during oncogenesis induced by nanoDEN.
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Asteraceae/química , Dietilnitrosamina/toxicidade , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Etanol , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Nanoestruturas , Extratos Vegetais/química , Distribuição Aleatória , Microambiente Tumoral/efeitos dos fármacosRESUMO
PURPOSE: To compare the efficacy and safety of viscocanalostomy plus near-360-degree suture trabeculotomy (VST) with viscocanalostomy plus rigid probe trabeculotomy (VT) in treating primary congenital glaucoma (PCG) over a one-year follow-up. METHODS: This consecutive retrospective study included patients with PCG confirmed within 3 years of age from March 2017 to October 2019. Efficacy was evaluated by comparing the postoperative intraocular pressure (IOP) curve and the success rate at one year after surgery. Safety was assessed by comparing the postoperative complications. The number of anti-glaucoma agents, horizontal corneal diameter (HCD) and cup-to-disc ratio (C/D) of the two surgical methods were also compared. RESULTS: Data of 90 eyes from 61 patients were analysed. The baseline parameters of the two groups were similar. The IOP at 12 months after surgery in the VST group was 12.7 ± 4.8 mmHg, while that in the VT group was 15.8 ± 6.5 mmHg. The IOP at 6, 9 and 12 months postoperatively in the VST group was significantly lower than in the VT group (p < 0.05). Viscocanalostomy plus near-360-degree suture trabeculotomy (VST) remained a significant favourable factor for complete one-year success (93.6% versus 74.4%, p = 0.005) but not qualified one-year success (97.9% versus 88.4%, p = 0.06). The number of anti-glaucoma agents, HCD and C/D were reduced in both groups. Postoperative complications were not significantly different between the two groups. CONCLUSIONS: In children with PCG, VST provides a more durable IOP control than VT over the one-year follow-up, with a similar safety profile.
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Glaucoma , Trabeculectomia , Criança , Seguimentos , Glaucoma/congênito , Glaucoma/cirurgia , Humanos , Pressão Intraocular , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Esclera/cirurgia , Suturas , Trabeculectomia/métodos , Resultado do TratamentoRESUMO
Developing the highly efficient and low-cost electrocatalysts for the oxygen evolution reactions (OERs), as vital half reactions of water splitting, is crucial for renewable energy technology. The electrocatalysts based on multi-component and hierarchically structured non-noble metal hydr(oxy)oxide materials are of great prospects. Herein, we report an efficient strategy at low temperatures for synthesizing amorphous iron-doped cobalt-molybdenum ultrathin hydroxide (Fe-CoMo UH) nanosheets. Benefiting from the ultrathin amorphous structure and multi-metal coordination, Fe-CoMo UH nanosheets exhibit outstanding performance for OERs with a low overpotential of 245 mV at 10 mA cm-2, a small Tafel slope of 37 mV dec-1 and an excellent stability for 90 h. The mass activity of Fe-CoMo UH is higher than that of commercial Ir/C and most of the transition metal hydroxide catalysts. This work provides a feasible consideration for the construction of promising efficient non-noble metal catalysts.
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Over the past decades, metal selenides have drawn considerable attention due to their high theoretical specific capacity. However, huge volume changes and sluggish electrochemical transfer kinetics hinder their applications in energy storage and conversion. In this work, we demonstrate an efficient and ingenious synthesis strategy to regulate nickel selenide electrodes by the introduction of copper and in situ coating with carbon (Cu-NiSe2@C). When used as anodes for lithium-ion batteries, the as-synthesized Cu-NiSe2@C delivered a high capacity of 1630 mA h g-1 at 1.0 A g-1 after 200 cycles and excellent rate performance as well as long-term cycling stability with a high capacity of 489 mA h g-1 at 10 A g-1 after 20 000 cycles. When coupled with a commercial LiFePO4 cathode, the full cells showed a high capacity of 463 mA h g-1 at 0.2 A g-1. Their superior electrochemical performance can be attributed to the synergistic effect of the in situ carbon coating and copper doping, which can promote the electron/ion transfer kinetics, as well as alleviate the volume expansion during cycling. This work will open new opportunities for the development of high-performance anodes for lithium storage.
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The development of metal-organic frameworks (MOFs) as high-efficiency electrocatalysts for water splitting has attracted special attention due to their unique structural features including high porosity, large surface areas, high concentrations of active sites, uniform pore sizes and shapes, etc. Most of the related reports focus on the in situ generation of high-efficiency electrocatalysts by annealed MOFs. However, the pyrolysis process usually destroys the porous structure of MOFs and reduces the number of active sites due to the absence of organic ligands and agglomeration of metal centers. In this work, we prepared unique NiCo-MOF hollow nanospheres (NiCo-MOF HNSs) by a solvothermal method and further fabricated Fe-doped NiCo-MOF HNSs (Fe@NiCo-MOF HNSs) by a simple impregnation-drying method. Significant enhancement of electrocatalytic activity of Fe@NiCo-MOF HNSs was witnessed because of the doped Fe. Compared with the parent NiCo-MOF HNSs, the optimized Fe@NiCo-MOF HNSs exhibited a lower overpotential of 244 mV at 10 mA·cm-2 with a smaller Tafel slope of 48.61 mV·dec-1, which was lowered by ca. 90 mV due to the influence of Fe doping on the electronic structure of the active centers of Ni and Co. The above materials also displayed excellent stability without obvious activity decay for at least 16 hours. These findings present a new entry in the design and fabrication of high-efficiency MOF-based electrocatalysts for energy conversion.
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The development of high-efficiency nonprecious electrocatalysts based on inexpensive and Earth abundant elements is of great significance for renewable energy technologies. Group VIII transition metal phosphides (TMPs) gradually stand out due to their intriguing properties including low resistance and superior catalytic activity and stability. Herein, we adopt a unique MOF-derived strategy to synthesize transition metal phosphide nanoboxes which can be employed as electrocatalysts for the hydrogen evolution reaction. During this process, we converted a Co-MOF to a CoNi-MOF by ion exchange and low-temperature phosphating to achieve CoNiP nanoboxes. The CoNiP nanoboxes can reach a current density of 10 mA cm-2 at a low overpotential of 138 mV with a small Tafel slope of 65 mV dec-1.
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The development of bifunctional non-noble metal electrocatalysts demonstrating high activity and stability for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is of great significance for renewable and clean energy. In this work, we report hierarchically structured integrated Fe-MoS2/Ni3S2/NF (NF = nickel foam) materials prepared by a facile in situ solvothermal method, and among them, the Fe-doped MoS2 was assembled into spine-like nanorods. The optimized electrocatalyst (denoted as Fe-MoS2/Ni3S2/NF-2) demonstrated excellent activity and durability for performing the HER and OER in an alkaline electrolyte (pH = 14) with low overpotentials of 130.6 mV and 256 mV (vs. RHE) at a current density of 10 mA cm-2, as well as no significant loss in catalytic performance even after 2000 cyclic voltammetry (CV) cycles. An outstanding durability of 180 h could be achieved for OER. The overall water splitting made up of the two-electrode system with Fe-MoS2/Ni3S2/NF-2 as both the anode and the cathode required a voltage of only 1.61 V to drive a current density of 10 mA cm-2 along with an outstanding long-term stability of 20 h, displaying its great potential for application in water splitting. The effective construction of multi-component synergistic structures shows a good pathway for high-performance electrocatalysis and energy storage.
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Background and aims: Lipid nanoparticles (LNs) are widely applied in drug delivery systems because they can incorporate and stabilize lipophilic and hydrophilic molecules. LNs are generally considered quite safe and convenient for in vivo applications. However, we previously observed that certain types of LNs could cause a loss of Kupffer cells, a kind of resident macrophage in the liver. As a result, we investigated the details of this phenomenon. Methods: MTT assay, Annexin-V-FITC/PI double staining, JC-1 staining, flow cytometry, Western blot and transmission electron microscopy were used in cell-based experiments. Additionally, serum biochemical analyses, H&E staining and immunofluorescence staining were performed to detect the acute and chronic changes of tissue structure and the number of Kupffer cells in mouse liver tissue samples. Results: Application of LN depolarized and swelled the mitochondria of Raw264.7 cells, and disrupted the balance of Bax/Bcl-2. This led to cleavage and activation of caspase-3 and PARP, and then induced apoptosis of Raw264.7 cells. In addition, either acute or chronic applications of LN were sufficient to disrupt the structure of the hepatic portal vein and reduce the number of Kupffer cells in mice. Conclusions: LNs could induce apoptosis of macrophages through a mitochondrial-dependent pathway.
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Apoptose , Lipídeos/química , Macrófagos/metabolismo , Mitocôndrias/metabolismo , Nanopartículas/química , Animais , Sobrevivência Celular , Células Hep G2 , Hepatócitos/citologia , Humanos , Células de Kupffer/citologia , Macrófagos/ultraestrutura , Masculino , Camundongos , Nanopartículas/ultraestrutura , Células RAW 264.7 , Transdução de Sinais , Proteína X Associada a bcl-2/metabolismoRESUMO
OBJECTIVES: To estimate the current prevalence of cardiovascular disease risk factors (CRFs) and renal disorders across serum uric acid (SUA) quartiles, and evaluate the relationships between SUA and CRFs and renal diseases in Shanghai population. STUDY DESIGN: Observational, cross-sectional study. SETTING: Data were obtained from the physical check-up of local residents at three hospitals in Shanghai. PARTICIPANTS: Residents were invited to take part in a physical check-up and provided informed consent. Exclusion criteria were diseases that resemble cancer, hepatic disease, and other coexisting illnesses including autoimmune kidney diseases and renal artery stenosis, individuals treated with xanthine oxidase inhibitors, and those with incomplete information. There are 26 768 individuals in our study. PRIMARY AND SECONDARY OUTCOME MEASURES: Hyperuricaemia was defined as SUA ≥7 mg/dL in men and ≥6 mg/dL in women or taking xanthine oxidase inhibitors. Subjects were divided into gender-specific quartiles. We estimate the prevalence of CRFs and renal disorders across SUA quartiles. The relationships between SUA and CRFs and renal disorders in both genders were evaluated using logistic regression analysis. RESULTS: There was a significant increase in the prevalence of major CRFs and renal diseases across SUA quartiles in a separate analysis among men and women (all p trend <0.001). After multiple adjustment, hyperuricaemia positively correlated with obesity (male OR=3.165, p<0.001; female OR=3.776, p<0.001), hypertension (male OR=1.341, p<0.001; female OR=1.289, p=0.006), dyslipidaemia (male OR=2.490, p<0.001; female OR=3.614, p<0.001), chronic kidney disease (male OR=7.081, p<0.001; female OR=11.571, p<0.001) and nephrolithiasis (male OR=1.469, p<0.001; female OR=1.242, p=0.041), but negatively correlated with diabetes mellitus (male OR=0.206, p<0.001; female OR=0.524, p<0.001). There was a stronger association between hyperuricaemia and clustered CRFs as well as chronic kidney disease in women than in men. CONCLUSIONS: In Shanghai population, concomitant with the elevated level of SUA, the prevalence of CRFs and renal diseases was rising. Hyperuricaemia was significantly associated with CRFs and renal disorders, especially in women.