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1.
J Phys Chem Lett ; 14(36): 8069-8076, 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37656051

RESUMEN

The oxygen evolution reaction (OER) from water is a sequential oxidation reaction process, involved in transformation of multiple reaction intermediates. For photo(electro)catalytic OER, revealing the intermediates transformation kinetics is quite challenging due to its coupling with photogenerated charge dynamics. Herein, we specifically study the transformation kinetics of the OER intermediates in rationally thin hematite photoanodes through increasing the ratio between surface intermediates and photogenerated charges in bulk. We directly identify the formation and consumption kinetics of one-hole OER intermediate (FeIV═O) in photoelectrochemical water oxidation using operando transient absorption (TA) spectroscopy. The microsecond formation kinetics of the FeIV═O species are sensitively changed by the excitation mode of Fe2O3. The subsecond consumption kinetics are closely dependent on surface FeIV═O species density, demonstrating that the cooperation of FeIV═O intermediates is the key to accelerating water oxidation kinetics on the Fe2O3 surface. This work provides insight into understanding and controlling water oxidation reaction kinetics on Fe2O3 surface.

2.
Front Neurosci ; 17: 1106023, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37397445

RESUMEN

Background: This study aimed to comprehensively summarize the knowledge structure and research hotspots of ophthalmology in the field of neuroscience through bibliometric and visual analysis. Methods: We searched the Web of Science Core Collection database for articles from 2002 to 2021 related to ophthalmology in the field of neuroscience. Using VOSviewer and CiteSpace, bibliometric analysis was conducted on the number of annual ophthalmology publications, authors, organizations, countries, journals, cited references, keywords, and burst keywords. Results: A total of 9,179 articles were published from 34,073 authors, 4,987 organizations, and 87 countries. The cited references in these articles were published in 23,054 journals. Moreover, there were 30,864 keywords among the 9,179 articles. Notably, scholars have increasingly begun paying attention to ophthalmology in the field of neuroscience in the past 20 years. Claudio Babiloni published the most articles. The University of Washington had the greatest number of articles. The United States, Germany, and England led in the number of articles published. The Journal of Neuroscience was the most cited. The article with the highest outbreak intensity was an article published by Maurizio Corbetta in Nature Reviews Neuroscience in 2002 entitled "Control of goal-directed and stimulus-driven attention in the brain." The most important keyword was the brain, and the top burst keyword was functional connectivity. Conclusion: This study visualized ophthalmology research in the field of neuroscience through bibliometric analysis and predicted potential research trends in future to help clinicians and basic researchers provide diversified perspectives and further carry out in-depth research on ophthalmology.

3.
ACS Appl Mater Interfaces ; 15(24): 29586-29596, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37302102

RESUMEN

Salt lake brine has become a promising lithium resource, but it remains challenging to separate Li+ ions from the coexisting ions. We designed a membrane electrode having conductive and hydrophilic bifunctionality based on the H2TiO3 ion sieve (HTO). Reduced graphene oxide (RGO) was combined with the ion sieve to improve electrical conductivity, and tannic acid (TA) was polymerized on the surface of ion sieve to enhance hydrophilicity. These bifunctional modification at the microscopic level improved the electrochemical performance of the electrode and facilitated ion migration and adsorption. Poly(vinyl alcohol) (PVA) was used as a binder to further intensify the macroscopic hydrophilicity of the HTO/RGO-TA electrode. Lithium adsorption capacity of the modified electrode in 2 h reached 25.2 mg g-1, more than double that of HTO (12.0 mg g-1). The modified electrode showed excellent selectivity for Na+/Li+ and Mg2+/Li+ separation and good cycling stability. The adsorption mechanism follows ion exchange, which involves H+/Li+ exchange and Li-O bond formation in the [H] layer and [HTi2] layer of HTO.

4.
Front Immunol ; 14: 1294459, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38162649

RESUMEN

Background: Disulfidptosis, a newly defined type of programmed cell death, has emerged as a significant regulatory process in the development and advancement of malignant tumors, such as lower-grade glioma (LGG). Nevertheless, the precise biological mechanisms behind disulfidptosis in LGG are yet to be revealed, considering the limited research conducted in this field. Methods: We obtained LGG data from the TCGA and CGGA databases and performed comprehensive weighted co-expression network analysis, single-sample gene set enrichment analysis, and transcriptome differential expression analyses. We discovered nine genes associated with disulfidptosis by employing machine learning methods like Cox regression, LASSO regression, and SVM-RFE. These were later used to build a predictive model for patients with LGG. To confirm the expression level, functional role, and impact on disulfidptosis of ABI3, the pivotal gene of the model, validation experiments were carried out in vitro. Results: The developed prognostic model successfully categorized LGG patients into two distinct risk groups: high and low. There was a noticeable difference in the time the groups survived, which was statistically significant. The model's predictive accuracy was substantiated through two independent external validation cohorts. Additional evaluations of the immune microenvironment and the potential for immunotherapy indicated that this risk classification could function as a practical roadmap for LGG treatment using immune-based therapies. Cellular experiments demonstrated that suppressing the crucial ABI3 gene in the predictive model significantly reduced the migratory and invasive abilities of both SHG44 and U251 cell lines while also triggering cytoskeletal retraction and increased cell pseudopodia. Conclusion: The research suggests that the prognostic pattern relying on genes linked to disulfidptosis can provide valuable insights into the clinical outcomes, tumor characteristics, and immune alterations in patients with LGG. This could pave the way for early interventions and suggests that ABI3 might be a potential therapeutic target for disulfidptosis.


Asunto(s)
Glioma , Humanos , Glioma/genética , Glioma/terapia , Inmunoterapia , Apoptosis , Línea Celular , Aprendizaje Automático , Microambiente Tumoral/genética , Proteínas Adaptadoras Transductoras de Señales
5.
Front Pharmacol ; 13: 898519, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105222

RESUMEN

Background: Accurate target identification of small molecules and downstream target annotation are important in pharmaceutical research and drug development. Methods: We present TAIGET, a friendly and easy to operate graphical web interface, which consists of a docking module based on AutoDock Vina and LeDock, a target screen module based on a Bayesian-Gaussian mixture model (BGMM), and a target annotation module derived from >14,000 cancer-related literature works. Results: TAIGET produces binding poses by selecting ≤5 proteins at a time from the UniProt ID-PDB network and submitting ≤3 ligands at a time with the SMILES format. Once the identification process of binding poses is complete, TAIGET then screens potential targets based on the BGMM. In addition, three medical experts and 10 medical students curated associations among drugs, genes, gene regulation, cancer outcome phenotype, 2,170 cancer cell types, and 73 cancer types from the PubMed literature, with the aim to construct a target annotation module. A target-related PPI network can be visualized by an interactive interface. Conclusion: This online tool significantly lowers the entry barrier of virtual identification of targets for users who are not experts in the technical aspects of virtual drug discovery. The web server is available free of charge at http://www.taiget.cn/.

6.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34698349

RESUMEN

Target identification of small molecules is an important and still changeling work in the area of drug discovery, especially for botanical drug development. Indistinct understanding of the relationships of ligand-protein interactions is one of the main obstacles for drug repurposing and identification of off-targets. In this study, we collected 9063 crystal structures of ligand-binding proteins released from January, 1995 to April, 2021 in PDB bank, and split the complexes into 5133 interaction pairs of ligand atoms and protein fragments (covalently linked three heavy atoms) with interatomic distance ≤5 Å. The interaction pairs were grouped into ligand atoms with the same SYBYL atom type surrounding each type of protein fragment, which were further clustered via Bayesian Gaussian Mixture Model (BGMM). Gaussian distributions with ligand atoms ≥20 were identified as significant interaction patterns. Reliability of the significant interaction patterns was validated by comparing the difference of number of significant interaction patterns between the docked poses with higher and lower similarity to the native crystal structures. Fifty-one candidate targets of brucine, strychnine and icajine involved in Semen Strychni (Mǎ Qián Zǐ) and eight candidate targets of astragaloside-IV, formononetin and calycosin-7-glucoside involved in Astragalus (Huáng Qí) were predicted by the significant interaction patterns, in combination with docking, which were consistent with the therapeutic effects of Semen Strychni and Astragalus for cancer and chronic pain. The new strategy in this study improves the accuracy of target identification for small molecules, which will facilitate discovery of botanical drugs.


Asunto(s)
Teorema de Bayes , Ligandos , Unión Proteica , Reproducibilidad de los Resultados
7.
J Am Chem Soc ; 143(47): 19761-19768, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34793144

RESUMEN

Solar-powered water splitting is a dream reaction for constructing an artificial photosynthetic system for producing solar fuels. Natural photosystem II is a prototype template for research on artificial solar energy conversion by oxidizing water into molecular oxygen and supplying four electrons for fuel production. Although a range of synthetic molecular water oxidation catalysts have been developed, the understanding of O-O bond formation in this multielectron and multiproton catalytic process is limited, and thus water oxidation is still a big challenge. Herein, we report a trinuclear copper cluster that displays outstanding reactivity toward catalytic water oxidation inspired by multicopper oxidases (MCOs), which provides efficient catalytic four-electron reduction of O2 to water. This synthetic mimic exhibits a turnover frequency of 20000 s-1 in sodium bicarbonate solution, which is about 150 and 15 times higher than that of the mononuclear Cu catalyst (F-N2O2Cu, 131.6 s-1) and binuclear Cu2 complex (HappCu2, 1375 s-1), respectively. This work shows that the cooperation between multiple metals is an effective strategy to regulate the formation of O-O bond in water oxidation catalysis.

8.
Mar Drugs ; 18(8)2020 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-32726987

RESUMEN

With twice the number of cancer's deaths, cardiovascular diseases have become the leading cause of death worldwide. Atherosclerosis, in particular, is a progressive, chronic inflammatory cardiovascular disease caused by persistent damage to blood vessels due to elevated cholesterol levels and hyperlipidemia. This condition is characterized by an increase in serum cholesterol, triglycerides, and low-density lipoprotein, and a decrease in high-density lipoprotein. Although existing therapies with hypolipidemic effects can improve the living standards of patients with cardiovascular diseases, the drugs currently used in clinical practice have certain side effects, which insists on the need for the development of new types of drugs with lipid-lowering effects. Some marine-derived substances have proven hypolipidemic activities with fewer side effects and stand as a good alternative for drug development. Recently, there have been thousands of studies on substances with lipid-lowering properties of marine origin, and some are already implemented in clinical practice. Here, we summarize the active components of marine-derived products having a hypolipidemic effect. These active constituents according to their source are divided into algal, animal, plant and microbial and contribute to the development and utilization of marine medicinal products with hypolipidemic effects.


Asunto(s)
Organismos Acuáticos/metabolismo , Aterosclerosis/tratamiento farmacológico , Dislipidemias/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Metabolismo de los Lípidos/efectos de los fármacos , Animales , Aterosclerosis/sangre , Aterosclerosis/patología , Dislipidemias/sangre , Humanos , Hipolipemiantes/química , Hipolipemiantes/aislamiento & purificación , Lípidos/sangre , Estructura Molecular , Placa Aterosclerótica , Metabolismo Secundario
9.
Biomed Rep ; 9(6): 483-490, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30546875

RESUMEN

Osteoporosis is a polygenic disorder and has been demonstrated to be associated with ~30 candidate genes, the majority of which have also been implicated in the regulation of bone mineral density (BMD). Vitamin D receptor (VDR) is the candidate gene that has been most extensively studied. Certain studies have reported that the VDR single nucleotide polymorphism ApaI is associated with the risk of osteoporosis in Caucasian and African women. However, this association has not yet been studied in postmenopausal Han Chinese women in the Xinjiang area. In the present study, ApaI polymorphisms of VDR were defined by polymerase chain reaction-restriction fragment length polymorphism, in order to analyze the distribution of ApaI polymorphisms in postmenopausal Han Chinese women from Xinjiang. BMD was measured by dual energy X-ray absorptiometry at the lumbar spine (L2-4), Ward's triangle, great trochanter and femoral shaft. A total of 336 women were included in this study. The genotype distribution of ApaI was consistent with the Hardy-Weinberg equilibrium (all P>0.05). There were no significant differences in ApaI genotype frequencies between the 90 cases in the osteoporosis group and 246 cases in the non-osteoporosis group (P=0.946). Meanwhile, it was identified that BMD values of the tested locations were negatively correlated with age (P<0.05) and positively correlated with body mass index (BMI; P<0.05). On further attribution risk analysis, BMD was identified as a risk factor [odds ratio (OR): 0.464, 95% confidence interval (CI): 0.372-0.580, P=0.001] and BMI a protective factor (OR: 1.502, 95% CI: 1.008-2.240, P=0.032) in osteoporosis. When BMD was adjusted for confounding factors including age and BMI, it was observed that the ApaI polymorphism was not associated with BMD at the sites tested (P>0.05). In conclusion, the present study identified no significant association of the common VDR polymorphism ApaI with BMD at several skeletal sites in postmenopausal Han Chinese women in the Xinjiang area. Age was negatively correlated with BMD at different sites and identified as a risk factor; while BMI was positively correlated with BMD and identified as a protective factor.

10.
Cytotechnology ; 66(1): 51-61, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24091880

RESUMEN

Daphnoretin is a bicoumarin compound isolated from a natural product, Wikstroemia indica, which has been used to treat many diseases. It has strong antiviral and anti-tumor activities. Taking the anti-tumor activity of daphnoretin as a starting point, the present study aimed to test the pro-apoptotic effect of daphnoretin and its underlying mechanism in HeLa cells. The inhibitory effects of daphnoretin on viability and proliferation of HeLa cells were determined by the MTT assay. Daphnoretin-induced apoptotic morphological changes were analyzed by mitochondrial membrane potential and Hoechst staining. The number and stage of apoptotic HeLa cells were determined by flow cytometry. Gene expression was determined by reverse-transcription polymerase chain reaction. Protein expression was determined by western blot. The caspase activity of HeLa cells was detected by a caspase-3 and caspase-9 colorimetric assay kit. We found that daphnoretin significantly inhibited HeLa cells' viability by the MTT assay and flow cytometry. The nuclei of the apoptotic cells exhibited strong, blue fluorescence in Hoechst staining. Bax mRNA and protein levels were increased while bcl-2 mRNA levels were decreased after daphnoretin treatment. Daphnoretin also activated both caspase-3 and caspase-9. These findings suggest that daphnoretin promotes apoptosis of HeLa cells in a mitochondria-mediated way. Daphnoretin therefore has potential to be a promising drug to treat uterine cervix cancer.

11.
Acta Pharmacol Sin ; 34(10): 1284-91, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24096643

RESUMEN

Hydrogen sulfide (H2S) along with carbon monoxide and nitric oxide is an important signaling molecule that has undergone large numbers of fundamental investigations. H2S is involved in various physiological activities associated with the regulation of homeostasis, vascular contractility, pro- and anti-inflammatory activities, as well as pro- and anti-apoptotic activities etc. However, the actions of H2S are influenced by its concentration, reaction time, and cell/disease types. Therefore, H2S is a signaling molecule without definite effect. The use of existing H2S donors is limited because of the instant release and short lifetime of H2S. Thus, translational medicine involving the sustained and controlled release of H2S is of great value for both scientific and clinical uses. H2S donation can be manipulated by different ways, including where H2S is given, how H2S is donated, or the specific structures of H2S-releasing drugs and H2S donor molecules. This review briefly summarizes recent progress in research on the physiological and pathological functions of H2S and H2S-releasing drugs, and suggests hope for future investigations.


Asunto(s)
Diseño de Fármacos , Sulfuro de Hidrógeno/metabolismo , Investigación Biomédica Traslacional , Animales , Apoptosis/fisiología , Homeostasis , Humanos , Sulfuro de Hidrógeno/administración & dosificación , Sulfuro de Hidrógeno/farmacología , Inflamación/patología , Transducción de Señal/fisiología
12.
Oxid Med Cell Longev ; 2012: 878052, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23304257

RESUMEN

Hydrogen sulfide (H(2)S) has historically been considered to be a toxic gas, an environmental and occupational hazard. However, with the discovery of its presence and enzymatic production through precursors of L-cysteine and homocysteine in mammalian tissues, H(2)S has recently received much interest as a physiological signaling molecule. H(2)S is a gaseous messenger molecule that has been implicated in various physiological and pathological processes in mammals, including vascular relaxation, angiogenesis, and the function of ion channels, ischemia/reperfusion (I/R), and heart injury. H(2)S is an endogenous neuromodulator and present studies show that physiological concentrations of H(2)S enhance NMDA receptor-mediated responses and aid in the induction of hippocampal long-term potentiation. Moreover, in the field of neuronal protection, physiological concentrations of H(2)S in mitochondria have many favorable effects on cytoprotection.


Asunto(s)
Sulfuro de Hidrógeno/metabolismo , Mitocondrias/metabolismo , Mitocondrias/patología , Animales , Humanos , Enfermedades Mitocondriales/metabolismo , Enfermedades Mitocondriales/patología , Enfermedades Mitocondriales/fisiopatología , Modelos Biológicos
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