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1.
Small ; 20(23): e2307997, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38148323

RESUMO

Sulfide solid electrolytes (SSEs) are highly wanted for solid-state batteries (SSBs). While their liquid-phase synthesis is advantageous over their solid-phase strategy in scalable production, it confronts other challenges, such as low-purity products, user-unfriendly solvents, energy-inefficient solvent removal, and unsatisfactory performance. This article demonstrates that a suspension-based solvothermal method using single oxygen-free solvents can solve those problems. Experimental observations and theoretical calculations together show that the basic function of suspension-treatment is "interparticle-coupled unification", that is, even individually insoluble solid precursors can mutually adsorb and amalgamate to generate uniform composites in nonpolar solvents. This anti-intuitive concept is established when investigating the origins of impurities in SSEs electrolytes made by the conventional tetrahydrofuran-ethanol method and then searching for new solvents. Its generality is supported by four eligible alkane solvents and four types of SSEs. The electrochemical assessments on the former three SSEs show that they are competitive with their counterparts in the literature. Moreover, the synthesized SSEs presents excellent battery performance, showing great potential for practical applications.

2.
Inorg Chem ; 63(1): 485-493, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38101320

RESUMO

Lithium sulfide (Li2S) is a highly desired material for advanced batteries. However, its current industrial production is not suitable for large-scale applications in the long run because the process is carbon-emissive, energy-intensive, and cost-ineffective. This article demonstrates a new method that can overcome these challenges by reacting lithium sulfate (Li2SO4) with sodium sulfide. This approach, which seems unfeasible initially because Li2SO4 is barely soluble in ethanol at room temperature, becomes feasible when heated ethanol and an excess amount of Li2SO4 are used. More interestingly, product purification is easier than that in other metathetic reactions, thanks to the poor solubility of Li2SO4. In order to further minimize the overall costs of producing Li2S, the concomitant byproduct LiNaSO4 and the unfinished precursor Li2SO4 are converted into more valuable materials, Li2CO3 and Na2SO4. Moreover, the homemade Li2S is competitive with the commercial Li2S in cathode performance and gains further enhancement when being composited with the Co9S8 catalyst. Thus, this Li2SO4-based metathesis of Li2S has great potential for practical applications.

3.
J Am Chem Soc ; 145(24): 13392-13399, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37289031

RESUMO

The design and construction of organic afterglow materials is an attractive but formidably challenging task due to the low intersystem crossing efficiency and nonradiative decay. Here, we developed a host surface-induced strategy to achieve excitation wavelength-dependent (Ex-De) afterglow emission through a facile dropping process. The prepared PCz@dimethyl terephthalate (DTT)@paper system exhibits a room-temperature phosphorescence afterglow, with the lifetime up to 1077.1 ± 15 ms and duration time exceeding 6 s under ambient conditions. Furthermore, we can switch the afterglow emission on and off by adjusting the excitation wavelength below or above 300 nm, showing a remarkable Ex-De behavior. Spectral analysis demonstrated that the afterglow originates from the phosphorescence of PCz@DTT assemblies. The stepwise preparation process and detailed experiments (XRD, 1H NMR, and FT-IR analysis) proved the presence of strong intermolecular interactions between the carbonyl groups on the surface of DTT and the entire frame of PCz, which can inhibit the nonradiative processes of PCz to achieve afterglow emission. Theoretical calculations further manifested that DTT geometry alteration under different excitation beams is the main reason for the Ex-De afterglow. This work discloses an effective strategy for constructing smart Ex-De afterglow systems that can be fully exploited in a range of fields.

4.
Inorg Chem ; 62(14): 5576-5585, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36961493

RESUMO

Lithium sulfide (Li2S) is a critical material for clean energy technologies, i.e., the cathode material in lithium-sulfur batteries and the raw material for making sulfide solid electrolytes in all-solid-state batteries. However, its practical application at a large scale is hindered by its industrial production method of reducing lithium sulfate with carbon materials at high temperatures, which emits carbon dioxide and is time-consuming. We hereby report a method of synthesizing Li2S by thermally reducing lithium sulfate with aluminum. Compared with the carbothermal method, this aluminothermal approach has several advantages, such as operation at lower temperatures, completion in minutes, no emission of greenhouse gases, and valuable byproducts of aluminum oxide (Al2O3). The home-made Li2S demonstrates competitive performance in battery tests versus the commercial counterpart. Moreover, using the byproduct Al2O3 to coat the cathode side of the separator can enhance the battery's capacity without influencing its rate capability. Thus, this "one stone two birds" method has great potential for practical applications of developing Li-S batteries.

5.
Molecules ; 27(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35889533

RESUMO

To understand that 18ß-Glycyrrhetic acid 3-O-mono-ß-D-glucuronide (GAMG) showed better pharmacological activity and drug-like properties than 18ß-Glycyrrhizin (GL); a rapid and sensitive HPLC-MS/MS method was established for the simultaneous determination of GAMG and its metabolite 18ß-Glycyrrhetinic acid (GA) in rat plasma and tissues after oral administration of GAMG or GL. This analytical method was validated by linearity, LLOQ, specificity, recovery rate, matrix effect, etc. After oral administration, GAMG exhibited excellent Cmax (2377.57 ng/mL), Tmax (5 min) and AUC0-T (6625.54 mg/L*h), which was much higher than the Cmax (346.03 ng/mL), Tmax (2.00 h) and AUC0-T (459.32 mg/L*h) of GL. Moreover, GAMG had wider and higher tissue distribution in the kidney, spleen, live, lung, brain, etc. These results indicated that oral GAMG can be rapidly and efficiently absorbed and be widely distributed in tissues to exert stronger and multiple pharmacological activities. This provided a physiological basis for guiding the pharmacodynamic study and clinical applications of GAMG.


Assuntos
Ácido Glicirretínico , Ácido Glicirrízico , Animais , Glucuronidase/metabolismo , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/farmacologia , Ácido Glicirrízico/metabolismo , Ratos , Espectrometria de Massas em Tandem
6.
Bioorg Chem ; 110: 104755, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33652342

RESUMO

To develop new anti-inflammatory drugs for the prevention and treatment of acute kidney injury, a series of novel glycyrrhetic ureas were designed, synthesized and evaluated for anti-inflammatory activity using RAW264.7 cells. Compounds 5r-5u (2.04, 2.50, 3.25 and 2.48 µM, respectively) with acidic or neutral amino acid showed potent anti-inflammatory activity (IC50 = 2-3 µM for NO inhibition), amongst them, compound 5r also inhibited tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in a dose-dependent manner. In cisplatin-induced AKI mice model, compound 5r significantly reduced the level of pro-inflammatory factors, ameliorated the pathological damage of kidney tissue, and maintained the normal metabolic capacity.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/síntese química , Ureia/análogos & derivados , Ureia/síntese química , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Cisplatino/toxicidade , Desenho de Fármacos , Ácido Glicirretínico/farmacologia , Inflamação/tratamento farmacológico , Camundongos , Células RAW 264.7 , Ureia/farmacologia
7.
Chem Soc Rev ; 49(10): 3040-3071, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32292941

RESUMO

Lithium-ion batteries have had a tremendous impact on several sectors of our society; however, the intrinsic limitations of Li-ion chemistry limits their ability to meet the increasing demands of developing more advanced portable electronics, electric vehicles, and grid-scale energy storage systems. Therefore, battery chemistries beyond Li ions are being intensively investigated and need urgent breakthroughs toward commercial applications, wherein the use of metallic Li is one of the most intuitive choices. Despite several decades of oblivion due to safety concerns regarding the growth of Li dendrites, Li-metal anodes are now poised to be revived because of the advances in investigative tools and globally invested efforts. In this review, we first summarize the existing issues with regard to Li anodes and their underlying reasons and then highlight the recent progress made in the development of high-performance Li anodes. Finally, we propose the persisting challenges and opportunities toward the exploration of practical Li-metal anodes.

8.
Nano Lett ; 15(6): 3657-63, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-25971956

RESUMO

The quantum confinement and enhanced optical properties of silicon quantum dots (SiQDs) make them attractive as an inexpensive and nontoxic material for a variety of applications such as light emitting technologies (lighting, displays, sensors) and photovoltaics. However, experimental demonstration of these properties and practical application into optoelectronic devices have been limited as SiQDs are generally passivated with covalently bound insulating alkyl chains that limit charge transport. In this work, we show that strategically designed triphenylamine-based surface ligands covalently bonded to the SiQD surface using conjugated vinyl connectivity results in a 70 nm red-shifted photoluminescence relative to their decyl-capped control counterparts. This suggests that electron density from the SiQD is delocalized into the surface ligands to effectively create a larger hybrid QD with possible macroscopic charge transport properties.

9.
Cytokine ; 76(2): 163-169, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26044596

RESUMO

BACKGROUND: In recent years, Crk-like adapter protein (CrkL) has been identified as a key regulator in the epithelial-to-mesenchymal transition (EMT). However, the molecular mechanisms underlying the CC chemokine receptor 6 (CCR6) and chemokine (C-C motif) ligand 20 (CCL20)-induced EMT in gastric cancer are still unclear. METHODS: We conducted the immunohistochemistry and immunoblotting to detect the expression of CCR6 and CrkL in 90 cases of gastric cancer tissues and five kinds of cell lines. And then, gastric cancer cells were subjected to small interfering RNA (siRNA) treatment and in vitro assay. RESULTS: Both CCR6 and CrkL were aberrantly expressed in gastric cancer specimens and closely correlated with differentiation of cell lines. The expression of CCR6 and CrkL was also significantly associated with metastasis, stage, and poor prognosis of gastric cancer. In addition, we validated CCL20 activated the expression of p-CrkL, p-Erk1/2, p-Akt, vimentin, N-cadherin and MMP2 in MGC803 cells in a dose-dependent manner. However, si-CrkL abrogated the CCL20-induced p-Erk1/2, vimentin, N-cadherin and MMP2 expression. Most importantly, the knockdown of CrkL decreased migration and invasion of MGC803 cells. CONCLUSIONS: CrkL mediates CCL20/CCR6-induced EMT via Akt pathway, instead of Erk1/2 pathway in development of gastric cancer, which indicated CCL20/CCR6-CrkL-Erk1/2-EMT pathway may be targeted to antagonize the progression of gastric cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Quimiocina CCL20/fisiologia , Transição Epitelial-Mesenquimal , Proteínas Nucleares/fisiologia , Receptores CCR6/fisiologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/fisiopatologia , Proteínas Adaptadoras de Transdução de Sinal/deficiência , Proteínas Adaptadoras de Transdução de Sinal/genética , Idoso , Caderinas/genética , Caderinas/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Feminino , Seguimentos , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Pessoa de Meia-Idade , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Proteína Oncogênica v-akt/metabolismo , Prognóstico , RNA Interferente Pequeno/genética , Transdução de Sinais , Neoplasias Gástricas/imunologia , Vimentina/metabolismo
10.
Med Sci Monit ; 21: 3320-6, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26520674

RESUMO

BACKGROUND: The aim of this study was to investigate the feasibility and clinical value of transvaginal surgical treatment for cesarean scar pregnancy (CSP-II). MATERIAL AND METHODS: This study was a retrospective analysis of 25 CSP-II patients who received transvaginal surgical treatments. These patients were admitted in our hospital between January 2010 and June 2012. RESULTS: All surgical treatments were successful without overt complications. The average operation time was 61.5 minutes, the average intraoperative blood loss was 60.5 ml, the average hospital stay was 9.4 days and the average time that blood ß-human chorionic gonadotropin (ß-HCG) returned to normal range was 15 days. In all 25 patients, the cesarean scar mass located at the anterior wall of the lower uterine segment disappeared by B-ultrasound examination within 1 or 2 weeks after surgery. Postoperatively, the normal menstrual period started again with an average time of 28.9 days. No menstruation-related abnormalities, such as menstrual dripping or an abnormal amount of blood, were reported after surgery. CONCLUSIONS: Transvaginal surgery for CSP-II is a novel surgical approach. It has several advantages, including a thorough one-time treatment lesion clearance, short operation time, minimized trauma, minimal intraoperative blood loss, quick reduction of blood ß-HCG, and rapid menstruation recovery. It is a simple and feasible surgical approach of great clinical value and few treatment-related complications.


Assuntos
Cesárea/efeitos adversos , Cicatriz/cirurgia , Gravidez Ectópica/cirurgia , Adulto , Perda Sanguínea Cirúrgica , Gonadotropina Coriônica Humana Subunidade beta/sangue , Feminino , Seguimentos , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , Duração da Cirurgia , Admissão do Paciente , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
Bioorg Med Chem Lett ; 24(10): 2324-8, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24731281

RESUMO

A series of compounds which contain pyrazole, thiazole and naphthalene ring (1a-7a, 1b-7b, 1c-7c, 1d-7d) were firstly synthesized and their anti-proliferative activity, EGFR inhibitory activity, cytotoxicity and inhibition to Hela cell migration were evaluated. Compound 2-(3-(3,4-dimethylphenyl)-5-(naphthalen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazol-4(5H)-one (7d) displayed the most potent inhibitory activity (IC50=0.86µM for Hela and IC50=0.12µM for EGFR). Structure-activity relationship (SAR) analysis showed that the anti-proliferative activity was affected by A-ring-substituent (-OCH3>-CH3>-H>-Br>-Cl>-F). Docking simulation of compound 7d into EGFR active site showed that naphthalene ring of 7d with LYS721 formed two p-π bonds, which enhanced antitumor activity. Therefore, compound 7d may be developed as a potential antitumor agent.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Naftalenos/farmacologia , Neoplasias/tratamento farmacológico , Pirazóis/farmacologia , Tiazóis/farmacologia , Antineoplásicos/síntese química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Modelos Moleculares , Naftalenos/síntese química , Naftalenos/química , Neoplasias/patologia , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química
12.
Inorg Chem ; 53(20): 11289-97, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25265365

RESUMO

Lithium silicide (LixSi) is the lithiated form of silicon, one of the most promising anode materials for the next generation of lithium-ion batteries (LIBs). In contrast to silicon, LixSi has not been well studied. Herein we report a facile high-energy ball-milling-based synthesis of four phase-pure LixSi (x = 4.4, 3.75, 3.25, and 2.33), using hexane as the lubricant. Surprisingly, the obtained Li3.75Si phase shows significant downward shifts in all X-ray diffraction peak positions, compared with the standard. Our interpretation is that the high-energy ball-mill-synthesized Li3.75Si presents smaller internal pressures and larger lattice constants. The chemical-stability study reveals that only surface reactions occur after Li4.4Si and Li3.75Si are immersed in several battery-assembly-related chemicals. The thermal-stability study shows that Li4.4Si is stable up to 350 °C and Li3.75Si is stable up to 200 °C. This remarkable thermal stability of Li3.75Si is in stark contrast to the long-observed metastability for electrochemically synthesized Li3.75Si. The carbon encapsulation of Li4.4Si has also been studied for its potential applications in LIBs.

13.
Org Biomol Chem ; 12(6): 998-1008, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24382549

RESUMO

A series of novel 4,5-dihydropyrazole derivatives (4a-4t), containing the dinitrobenzotrifluoride moiety, as DNA gyrase inhibitors were designed and synthesized. Based on the preliminary results, compounds 4d, 4f and 4t with potent inhibitory activity in bacterial growth may be wonderful antibacterial agents; among them, compound 4t displayed the most potent activity with minimum inhibitory concentration (MIC) values of 3.125, 0.39, 0.39 and 0.39 µg mL(-1) against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli respectively, which was comparable with penicillin and kanamycin B with corresponding MIC values of 3.125, 3.125, 0.39, 0.39 µg mL(-1) and 1.562, 1.562, 1.562, 1.562 µg mL(-1), respectively. In particular, compound 4d showed the most potent anti-Gram-positive bacterial activity with a MIC value of 0.39 µg mL(-1) against the tested Gram-positive bacterial strains and exhibited the most potent B. subtilis DNA gyrase and S. aureus DNA gyrase inhibitory activity with an IC50 of 0.125 µg mL(-1). Docking simulation was performed to insert compound 4d into the S. aureus DNA gyrase active site to determine the probable binding conformation.


Assuntos
Antibacterianos/farmacologia , DNA Girase/metabolismo , Éteres Fenílicos/farmacologia , Pirazóis/farmacologia , Inibidores da Topoisomerase II/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/enzimologia , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Éteres Fenílicos/síntese química , Éteres Fenílicos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pirazóis/síntese química , Pirazóis/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/química
14.
Molecules ; 19(5): 6368-81, 2014 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-24853453

RESUMO

Glycyrrhizin (GA) analogs in the form of 3-glucuronides and 18-epimers were synthesized and their anticancer activities were evaluated. Alkaline isomerization of monoglucuronides is reported. In vitro and in vivo studies showed that glycyrrhetinic acid monoglucuronides (GAMGs) displayed higher anticancer activities than those of bisglucuronide GA analogs, while anticancer activity of the 18α-epimer was superior to that of the 18ß-epimer. 18α-GAMG was firstly nicely bound to epidermal growth factor receptor (EGFR) via six hydrogen bonds and one charge interaction, and the docking calculation proved the correlation between anticancer activities and EGFR inhibitory activities. Highly active 18α-GAMG is thus of interest for the further studies as a potential anticancer agent.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Receptores ErbB , Glucuronídeos/química , Ácido Glicirrízico/análogos & derivados , Animais , Antineoplásicos Fitogênicos/síntese química , Linhagem Celular Tumoral/efeitos dos fármacos , Técnicas de Química Sintética , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/química , Receptores ErbB/metabolismo , Feminino , Ácido Glicirretínico/química , Ácido Glicirrízico/química , Humanos , Ligação de Hidrogênio , Isomerismo , Masculino , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Terapia de Alvo Molecular , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Molecules ; 19(6): 7269-86, 2014 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24896265

RESUMO

A series of caffeic acid amides D1-D17 bearing 2,3,4,5-tetrahydrobenzo-[b][1,4]dioxocine units has been synthesized and their biological activities evaluated for potential antiproliferative and EGFR inhibitory activity. Of all the compounds studied, compound D9 showed the most potent inhibitory activity (IC50=0.79 µM for HepG2 and IC50=0.36 µM for EGFR). The structures of compounds were confirmed by 1H-NMR, ESI-MS and elemental analysis. Among all, the structure of compound D9 ((E)-N-(4-ethoxyphenyl)-3-(2,3,4,5-tetrahydrobenzo[b][1,4]dioxocin-8-yl)acrylamide) was also determined by single-crystal X-ray diffraction analysis. Compound D9 was found to be a potential antitumor agent according to biological activity, molecular docking, apoptosis assay and inhibition of HepG2.


Assuntos
Amidas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Ácidos Cafeicos/química , Movimento Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/metabolismo , Células Hep G2 , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Difração de Raios X
16.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(1): 12-9, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-24581122

RESUMO

OBJECTIVE: To explore the effects of stanniocalcin-1 (STC-1) and hypoxia-inducible factor-1α (HIF-1α) on the calcium and thus on the mitochondrial membrane potential (Δψm) in renal carcinoma cells. METHODS: We successfully established the renal carcinoma cell models with high HIF-1α gene expression. After various concentrations of STC-1 solutions were added to the culture medium, the proliferation of cells, expressions of HIF-1α and STC-1, levels of Ca(2+), Δψm, and mPTP were detected by MTT, RT-PCR, ELISA, fluorescence spectrophotometry, and ultraviolet spectrophotometry, respectively. RESULTS: The proliferation of renal carcinoma cells and Δψm were improved after HIF-1α gene transfection, STC-1 protein intervention, and STC-1 protein intervention after gene transfection. While the intracellular Ca(2+) level and mPTP were decreased significantly (P<0.05), all the changes were intensified with the gradual increase of STC-1. However, the increasing trend of cell proliferation gradually declined. CONCLUSION: HIF-1α may participate in malignant proliferation of renal carcinoma cells by promoting STC-1 proliferation or down-regulating Ca(2+); however, such an effect may be gradually attenuated due to the inhibitory effect of STC-1 on HIF-1α.


Assuntos
Carcinoma de Células Renais/patologia , Glicoproteínas/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Cálcio/metabolismo , Humanos , Células Tumorais Cultivadas
17.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 43(5): 528-34, 2014 09.
Artigo em Zh | MEDLINE | ID: mdl-25372636

RESUMO

OBJECTIVE: To investigate effects of stanniocalcin-1 (STC-1) on proliferation balance under hypoxic condition in renal cancer cells and its mechanism. METHODS: Hypoxic model was induced on renal cancer GRC-1 cells (Group H), the cells were treated with STC-1 protein at concentrations of 0.1 nmol/L (H1), 0.5 nmol/L (H2), 1.0 nmol/L (H3), or normal saline (H0) for 48 h, respectively. Cells proliferation was measured by MTT assay; mRNA and protein expressions of hypoxia inducible factor 1α (HIF-1α) and STC-1 in GRC-1 cells were detected by RT-PCR and ELISA, respectively; the intracellular levels of Ca2+ and adenosine triphosphate (ATP) were determined by fluorescence spectrophotometry and spectrophotometry, respectively. RESULTS: The expression of HIF-1α, STC-1 and Ca2+ levels were increased in GRC-1 cells under hypoxia condition; STC-1 reversed these changes in a dose-effect manner. Hypoxia significantly inhibited cell proliferation and the generation of ATP in GRC-1 cells and exogenous STC-1 reversed the effects of hypoxia; ATP generation increased gradually with increasing STC-1 concentration, but the cell proliferation was reduced. CONCLUSION: Exogenous STC-1 can promote the proliferation of renal cancer cells in hypoxia condition by reducing HIF-1α expression and Ca2+ content and increased ATP production, but the progressive inhibition of HIF-1 α hindered the renal carcinoma cell proliferation further, which indicates that STC-1 may be involved in anti-hypoxia proliferative balance of renal cancer cells.


Assuntos
Cálcio/metabolismo , Proliferação de Células , Glicoproteínas/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Renais/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , RNA Mensageiro
18.
Angew Chem Int Ed Engl ; 53(52): 14527-32, 2014 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-25367697

RESUMO

The synthesis of colloidal nanocrystals (NCs) of lithiated group 14 elements (Z=Si, Ge, and Sn) is reported, which are Li4.4 Si, Li3.75 Si, Li4.4 Ge, and Li4.4 Sn. Lix Z compounds are highly reactive and cannot be synthesized by existing methods. The success relied on separating the surface protection from the crystal formation and using a unique passivating ligand. Bare Lix Z crystals were first produced by milling elemental Li and Z in an argon-filled jar. Then, under the assistance of additional milling, hexyllithium was added to passivate the freshly generated Lix Z NCs. This ball-milling-assisted surface protection method may be generalized to similar systems, such as Nax Z and Kx Z. Moreover, Li4.4 Si and Li4.4 Ge NCs were conformally encapsulated in carbon fibers, providing great opportunities for studying the potential of using Lix Z to mitigate the volume-fluctuation-induced poor cyclability problem confronted by Z anodes in lithium-ion batteries.

19.
Materials (Basel) ; 17(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38793306

RESUMO

The electrocatalytic nitrogen reduction reaction (NRR) for synthesizing ammonia holds promise as an alternative to the traditional high-energy-consuming Haber-Bosch method. Rational and accurate catalyst design is needed to overcome the challenge of activating N2 and to suppress the competitive hydrogen evolution reaction (HER). Single-atom catalysts have garnered widespread attention due to their 100% atom utilization efficiency and unique catalytic performance. In this context, we constructed theoretical models of metal single-atom catalysts supported on titanate nanosheets (M-TiNS). Initially, density functional theory (DFT) was employed to screen 12 single-atom catalysts for NRR- and HER-related barriers, leading to the identification of the theoretically optimal NRR catalyst, Ru-TiNS. Subsequently, experimental synthesis of the Ru-TiNS single-atom catalyst was successfully achieved, exhibiting excellent performance in catalyzing NRR, with the highest NH3 yield rate reaching 15.19 µmol mgcat-1 h-1 and a Faradaic efficiency (FE) of 15.3%. The combination of experimental results and theoretical calculations demonstrated the efficient catalytic ability of Ru sites, validating the effectiveness of the constructed theoretical screening process and providing a theoretical foundation for the design of efficient NRR catalysts.

20.
ACS Appl Mater Interfaces ; 16(22): 28452-28460, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38775640

RESUMO

The electrocatalytic nitrogen reduction reaction (NRR) presents an alternative method for the Haber-Bosch process, and single-atom catalysts (SACs) to achieve efficient NRR have attracted considerable attention in the past decades. However, whether SACs are more suitable for NRR compared to atomic-cluster catalysts (ACCs) remains to be studied. Herein, we have successfully synthesized both the Fe monomers (Fe1) and trimers (Fe3) on nitrogen-doped carbon catalysts. Both the experiments and DFT calculations indicate that compared to the end-on adsorption of N2 on Fe1 catalysts, N2 activation is enhanced via the side-on adsorption on Fe3 catalysts, and the reaction follows the enzymatic pathway with a reduced free energy barrier for NRR. As a result, the Fe3 catalysts achieved better NRR performance (NH3 yield rate of 27.89 µg h-1 mg-1cat. and Faradaic efficiency of 45.13%) than Fe1 catalysts (10.98 µg h-1 mg-1cat. and 20.98%). Therefore, our research presents guidance to prepare more efficient NRR catalysts.

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