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1.
Small ; : e2311750, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459645

RESUMO

The commercialization of lithium-sulfur (Li-S) battery is seriously hindered by the shuttle behavior of lithium (Li) polysulfide, slow conversion kinetics, and Li dendrite growth. Herein, a novel hierarchical p-type iron nitride and n-type vanadium nitride (p-Fe2 N/n-VN) heterostructure with optimal electronic structure, confined in vesicle-like N-doped nanofibers (p-Fe2 N/n-VN⊂PNCF), is meticulously constructed to work as "one stone two birds" dual-functional hosts for both the sulfur cathode and Li anode. As demonstrated, the d-band center of high-spin Fe atom captures more electrons from V atom to realize more π* and moderate σ* bond electron filling and orbital occupation; thus, allowing moderate adsorption intensity for polysulfides and more effective d-p orbital hybridization to improve reaction kinetics. Meanwhile, this unique structure can dynamically balance the deposition and transport of Li on the anode; thereby, more effectively inhibiting Li dendrite growth and promoting the formation of a uniform solid electrolyte interface. The as-assembled Li-S full batteries exhibit the conspicuous capacities and ultralong cycling lifespan over 2000 cycles at 5.0 C. Even at a higher S loading (20 mg cm-2 ) and lean electrolyte (2.5 µL mg-1 ), the full cells can still achieve an ultrahigh areal capacity of 16.1 mAh cm-2 after 500 cycles at 0.1 C.

2.
Arterioscler Thromb Vasc Biol ; 43(11): e468-e489, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37767704

RESUMO

BACKGROUND: Current therapies cannot completely reverse advanced atherosclerosis. High levels of amino acids, induced by Western diet, stimulate mTORC1 (mammalian target of rapamycin complex 1)-autophagy defects in macrophages, accelerating atherosclerotic plaque progression. In addition, autophagy-lysosomal dysfunction contributes to plaque necrotic core enlargement and lipid accumulation. Therefore, it is essential to investigate the novel mechanism and molecules to reverse amino acid-mTORC1-autophagy signaling dysfunction in macrophages of patients with advanced atherosclerosis. METHODS: We observed that Gpr137b-ps (G-protein-coupled receptor 137B, pseudogene) was upregulated in advanced atherosclerotic plaques. The effect of Gpr137b-ps on the progression of atherosclerosis was studied by generating advanced plaques in ApoE-/- mice with cardiac-specific knockout of Gpr137b-ps. Bone marrow-derived macrophages and mouse mononuclear macrophage cell line RAW264.7 cells were subjected to starvation or amino acid stimulation to study amino acid-mTORC1-autophagy signaling. Using both gain- and loss-of-function approaches, we explored the mechanism of Gpr137b-ps-regulated autophagy. RESULTS: Our results demonstrated that Gpr137b-ps deficiency led to enhanced autophagy in macrophages and reduced atherosclerotic lesions, characterized by fewer necrotic cores and less lipid accumulation. Knockdown of Gpr137b-ps increased autophagy and prevented amino acid-induced mTORC1 signaling activation. As the downstream binding protein of Gpr137b-ps, HSC70 (heat shock cognate 70) rescued the impaired autophagy induced by Gpr137b-ps. Furthermore, Gpr137b-ps interfered with the HSC70 binding to G3BP (Ras GTPase-activating protein-binding protein), which tethers the TSC (tuberous sclerosis complex) complex to lysosomes and suppresses mTORC1 signaling. In addition to verifying that the NTF2 (nuclear transport factor 2) domain of G3BP binds to HSC70 by in vitro protein synthesis, we further demonstrated that HSC70 binds to the NTF2 domain of G3BP through its W90-F92 motif by using computational modeling. CONCLUSIONS: These findings reveal that Gpr137b-ps plays an essential role in the regulation of macrophage autophagy, which is crucial for the progression of advanced atherosclerosis. Gpr137b-ps impairs the interaction of HSC70 with G3BP to regulate amino acid-mTORC1-autophagy signaling, and these results provide a new potential therapeutic direction for the treatment of advanced atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , RNA Longo não Codificante , Humanos , Camundongos , Animais , RNA Longo não Codificante/metabolismo , Aterosclerose/patologia , Placa Aterosclerótica/patologia , Macrófagos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Autofagia/fisiologia , Aminoácidos/metabolismo , Lipídeos , Mamíferos/genética
3.
Eur J Nutr ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703229

RESUMO

PURPOSE: The traditional Chinese herbal medicine Suaeda salsa (L.) Pall (S. salsa) with a digesting food effect was taken as the research object, and its chemical composition and action mechanism were explored. METHODS: The chemical constituents of S. salsa were isolated and purified by column chromatography, and their structures were characterized by nuclear magnetic resonance. The food accumulation model in mice was established, and the changes of the aqueous extract of S. salsa in gastric emptying and intestinal propulsion rate, colonic tissue lesions, serum brain-gut peptide hormone, colonic tissue protein expression, and gut microbiota structure were compared. RESULTS: Ten compounds were isolated from S. salsa named as naringenin (1), hesperetin (2), baicalein (3), luteolin (4), isorhamnetin (5), taxifolin (6), isorhamnetin-3-O-ß-D-glucoside (7), luteolin-3'-D-glucuronide (8), luteolin-7-O-ß-D-glucuronide (9), and quercetin-3-O-ß-D-glucuronide (10), respectively. The aqueous extract of S. salsa can improve the pathological changes of the mice colon and intestinal peristalsis by increasing the rate of gastric emptying and intestinal propulsion. By adjusting the levels of 5-HT, CCK, NT, SS, VIP, GT-17, CHE, MTL, and ghrelin, it can upregulate the levels of c-kit, SCF, and GHRL protein, and restore the imbalanced structure of gut microbiota, further achieve the purpose of treating the syndrome of indigestion. The effect is better with the increase of dose. CONCLUSION: S. salsa has a certain therapeutic effect on mice with the syndrome of indigestion. From the perspective of "brain-gut-gut microbiota", the mechanism of digestion and accumulation of S. salsa was discussed for the first time, which provided an experimental basis for further exploring the material basis of S. salsa.

4.
Phys Chem Chem Phys ; 26(20): 14857-14865, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38738300

RESUMO

Unveiling the role of heteroatom compounds in heavy oil viscosity is pivotal for finding targeted viscosity reduction methods to improve oil recovery. This research investigates the impact of heteroatoms in asphaltene molecules by utilizing quantum chemical calculations and molecular dynamics simulations to analyze their electrostatic potential characteristics, pairwise interactions, and dynamic behavior within realistic reservoirs. Heteroatom compounds can influence the molecular-level properties of asphaltenes and thus impact the macroscopic behavior of heavy oils. Research results suggest that the presence of ketone and aromatic rings in asphaltene molecules leads to the unrestricted movement of pi electrons due to their collective electronegativity. Two distinct configurations of asphaltene dimers, face-to-face, and edge-to-face, were observed. Intermolecular interactions were predominantly governed by van der Waals forces, highlighting their significant role in stabilizing asphaltene aggregates. The distribution of asphaltene molecules in the oil phase can be summarized as the "rebar-cement" theory. In the heteroatom-free system, the face-to-face peaks in the radial distribution function exhibit significantly reduced magnitudes compared to those in the heteroatom-containing system. This emphasizes the pivotal function of heteroatoms in connecting molecular components to form a more compact asphaltene structure, which may result in a higher viscosity of heavy oil. These findings give insight into the significance of heteroatoms in bridging molecular components and shaping the intricate structure of asphaltene and advance our understanding of heavy oil viscosity properties.

5.
Chem Biodivers ; 21(2): e202301639, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38062000

RESUMO

Cnidium officinale Makino (COM), a perennial herbaceous plant in the Apiaceous family, widely distribute in Eastern Asia and Asia-Temperate. It has a long history application as a traditional medicine for invigorating the blood and removing blood stasis, and also has been employed to diet, pesticide, herbal bathing materials, the cosmetic and skin care industry. However, there has been no associated review of literature in the past half a century (1967-2023). By searching the international authoritative databases and collecting 229 literatures closely related to COM, herewith a comprehensive and systematic review was conducted. The phytology includes plant distribution and botanical characteristics. The phytochemistry covers 8 major categories, 208 compounds in total, and the quantitative determination of 14 monomer compounds, total polyphenols and total flavonoids. The clinical trial in pregnant women and toxic experiments in mice, the pharmacology of 7 aspects and 82 frequently used prescriptions are summarized. It is expected that this paper will provide forward-looking scientific thinking and literature support for the further modern research, development and utilization of COM.


Assuntos
Cnidium , Medicina Tradicional , Gravidez , Humanos , Feminino , Camundongos , Animais , Cnidium/química , Etnofarmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Medicina Tradicional Chinesa
6.
Mikrochim Acta ; 191(6): 355, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809308

RESUMO

Carbon dots (CDs) are nanoscale carbon materials with unique optical properties and biocompatibility. Their applications are limited by their tendency to aggregate or oxidize in aqueous environments. Turning weakness to strengths, CDs can be incorporated with hydrogels, which are three-dimensional networks of crosslinked polymers that can retain large amounts of water. Hydrogels can provide a stable and tunable matrix for CDs, enhancing their fluorescence, stability, and functionality. CDs@hydrogels, known for their ease of synthesis, strong binding capabilities, and rich surface functional groups, have emerged as promising composite materials. In this review, recent advances in the synthesis and characterization of CDs@hydrogels, composite materials composed of CDs and various types of natural or synthetic hydrogels, are summarized. The potential applications of CDs@hydrogels in fluorescence sensing, adsorption, drug delivery, antibacterial activity, flexible electronics, and energy storage are also highlighted. The current challenges and future prospects of CDs@hydrogels systems for the novel functional materials are discussed.

7.
Arch Pharm (Weinheim) ; 357(1): e2300427, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37853667

RESUMO

Apostichopus japonicus, also known as Stichopus japonicus, with medicinal and food homologous figures, is a globally recognized precious ingredient with extremely high nutritional value. There is no relevant review available through literature search, so this article selects the research articles through the keywords "sea cucumber" and "Apostichopus japonicus (Stichopus japonicus)" in six professional databases, such as Wiley, PubMed, ScienceDirect, ACS, Springer, and Web of Science, from 2000 to the present, summarizing the extraction, isolation, and purification methods for the four major categories (polysaccharides, proteins and peptides, saponins, and other components) of the A. japonicus chemical substances and 10 effective biological activities of A. japonicus. Included are anticoagulation, anticancer/antitumor activities, hematopoiesis, regulation of gut microbiota, and immune regulatory activities that correspond to traditional efficacy. Literature support is provided for the development of medicines and functional foods and related aspects that play a leading role in future directions.


Assuntos
Saponinas , Pepinos-do-Mar , Stichopus , Animais , Stichopus/química , Stichopus/fisiologia , Relação Estrutura-Atividade , Alimentos
8.
J Environ Manage ; 364: 121473, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878582

RESUMO

The newly discovered ClO• and BrO• contribute to pollutant degradation in advanced oxidation processes, while acrylamide (AM) and acrylonitrile (ACN) are always the focus of scientists concerned due to their continuous production and highly toxic effects. Moreover, various particles with a graphene-like structure are the companions of AM/ACN in dry/wet sedimentation or aqueous phase existence, which play an important role in heterogeneous oxidation. Thus, this work focuses on the reaction mechanism and environmental effect of AM/ACN with ClO•/BrO•/HO• in the water environment under the influence of graphene (GP). The results show that although the reactivity sequence of AM and ACN takes the order of with HO• > with BrO• > with ClO•, the easiest channel always occurs at the same C-position of the two reactants. The reaction rate constants (k) of AM with three radicals are 2 times larger than that with ACN, and amide groups have a better ability to activate CC bonds than cyanide groups. The existence of GP can accelerate the target reaction, and the k increased by 9-13 orders of magnitude. The toxicity assessment results show that the toxic effect of most products is lower than that of parent compounds, but the environmental risk of products from ClO•/BrO•-adducts is higher than those from HO•-adducts. The oxidative degradation process based on ClO• and BrO• deserves special attention, and the catalytic effect of GP and its derivatives on the oxidation process is non-negligible.


Assuntos
Acrilamida , Acrilonitrila , Grafite , Oxirredução , Acrilonitrila/química , Acrilamida/química , Grafite/química , Poluentes Químicos da Água/química , Modelos Teóricos , Radical Hidroxila/química
9.
Molecules ; 29(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38675699

RESUMO

In the face of ongoing water pollution challenges, the intricate interplay between dissolved organic matter and disinfectants like chlorine gives rise to potentially harmful disinfection byproducts (DBPs) during water treatment. The exploration of DBP formation originating from amino acids (AA) is a critical focus of global research. Aromatic DBPs, in particular, have garnered considerable attention due to their markedly higher toxicity compared to their aliphatic counterparts. This work seeks to advance the understanding of DBP formation by investigating chlorination disinfection and kinetics using tyrosine (Tyr), phenylalanine (Phe), and tryptophan (Trp) as precursors. Via rigorous experiments, a total of 15 distinct DBPs with accurate molecular structures were successfully identified. The chlorination of all three AAs yielded highly toxic chlorophenylacetonitriles (CPANs), and the disinfectant dosage and pH value of the reaction system potentially influence chlorination kinetics. Notably, Phe exhibited the highest degradation rate compared to Tyr and Trp, at both the CAA:CHOCl ratio of within 1:2 and a wide pH range (6.0 to 9.0). Additionally, a neutral pH environment triggered the maximal reaction rates of the three AAs, while an acidic condition may reduce their reactivity. Overall, this study aims to augment the DBP database and foster a deeper comprehension of the DBP formation and relevant kinetics underlying the chlorination of aromatic AAs.


Assuntos
Aminoácidos Aromáticos , Desinfecção , Halogenação , Purificação da Água , Cinética , Aminoácidos Aromáticos/química , Purificação da Água/métodos , Desinfetantes/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
10.
Molecules ; 29(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38257310

RESUMO

The unrestricted utilization of antibiotics poses a critical challenge to global public health and safety. Levofloxacin (LEV) and sulfaphenazole (SPN), widely employed broad-spectrum antimicrobials, are frequently detected at the terminal stage of water treatment, raising concerns regarding their potential conversion into detrimental disinfection byproducts (DBPs). However, current knowledge is deficient in identifying the potential DBPs and elucidating the precise transformation pathways and influencing factors during the chloramine disinfection process of these two antibiotics. This study conducts a comprehensive analysis of reaction pathways, encompassing piperazine ring opening/oxidation, Cl-substitution, OH-substitution, desulfurization, and S-N bond cleavage, during chloramine disinfection. Twelve new DBPs were identified in this study, exhibiting stability and persistence even after 24 h of disinfection. Additionally, an examination of DBP generation under varying disinfectant concentrations and pH values revealed peak levels at a molar ratio of 25 for LEV and SPN to chloramine, with LEV contributing 11.5% and SPN 23.8% to the relative abundance of DBPs. Remarkably, this research underscores a substantial increase in DBP formation within the molar ratio range of 1:1 to 1:10 compared to 1:10 to 1:25. Furthermore, a pronounced elevation in DBP generation was observed in the pH range of 7 to 8. These findings present critical insights into the impact of the disinfection process on these antibiotics, emphasizing the innovation and significance of this research in assessing associated health risks.


Assuntos
Levofloxacino , Purificação da Água , Levofloxacino/farmacologia , Sulfafenazol , Cloraminas/farmacologia , Desinfecção , Antibacterianos/farmacologia
11.
Mol Cancer ; 22(1): 4, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624516

RESUMO

BACKGROUND: Metastatic colonization is one of the critical steps in tumor metastasis. A pre-metastatic niche is required for metastatic colonization and is determined by tumor-stroma interactions, yet the mechanistic underpinnings remain incompletely understood. METHODS: PCR-based miRNome profiling, qPCR, immunofluorescent analyses evaluated the expression of exosomal miR-141 and cell-to-cell communication. LC-MS/MS proteomic profiling and Dual-Luciferase analyses identified YAP1 as the direct target of miR-141. Human cytokine profiling, ChIP, luciferase reporter assays, and subcellular fractionation analyses confirmed YAP1 in modulating GROα production. A series of in vitro tumorigenic assays, an ex vivo model and Yap1 stromal conditional knockout (cKO) mouse model demonstrated the roles of miR-141/YAP1/GROα/CXCR1/2 signaling cascade. RNAi, CRISPR/Cas9 and CRISPRi systems were used for gene silencing. Blood sera, OvCa tumor tissue samples, and tissue array were included for clinical correlations. RESULTS: Hsa-miR-141-3p (miR-141), an exosomal miRNA, is highly secreted by ovarian cancer cells and reprograms stromal fibroblasts into proinflammatory cancer-associated fibroblasts (CAFs), facilitating metastatic colonization. A mechanistic study showed that miR-141 targeted YAP1, a critical effector of the Hippo pathway, reducing the nuclear YAP1/TAZ ratio and enhancing GROα production from stromal fibroblasts. Stromal-specific knockout (cKO) of Yap1 in murine models shaped the GROα-enriched microenvironment, facilitating in vivo tumor colonization, but this effect was reversed after Cxcr1/2 depletion in OvCa cells. The YAP1/GROα correlation was demonstrated in clinical samples, highlighting the clinical relevance of this research and providing a potential therapeutic intervention for impeding premetastatic niche formation and metastatic progression of ovarian cancers. CONCLUSIONS: This study uncovers miR-141 as an OvCa-derived exosomal microRNA mediating the tumor-stroma interactions and the formation of tumor-promoting stromal niche through activating YAP1/GROα/CXCRs signaling cascade, providing new insight into therapy for OvCa patients with peritoneal metastases.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Humanos , Animais , Camundongos , Feminino , Cromatografia Líquida , Proteômica , Espectrometria de Massas em Tandem , Neoplasias Ovarianas/genética , MicroRNAs/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Microambiente Tumoral
12.
Small ; 19(11): e2206926, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36658717

RESUMO

The slow sulfur oxidation-reduction kinetics are one of the key factors hindering the widespread use of lithium-sulfur batteries (LSBs). Herein, flower-shaped NiS2 -WS2 heterojunction as the functional intercalation of LSBs is successfully prepared, and effectively improved the reaction kinetics of sulfur. Flower-like nanospheres composed of ultra-thin nanosheets (≤10 nm) enhance quickly transfer of mass and charge. Meanwhile, the heterostructures simultaneously serve as an electron receptor and a donor, thereby simultaneously accelerating the bidirectional catalytic activity of reduction and oxidation reactions in the LSBs. In addition, the adsorption experiment, chemical state analysis of elements before and after the reaction and theoretical calculation have effectively verified that NiS2 -WS2 heterojunction nanospheres optimize the adsorption capacity and bidirectional catalytic effect of polysulfides. The results show that the initial discharge capacity of NiS2 -WS2 functional intercalation is as high as 1518.7 mAh g-1 at 0.2 C. Even at a high current density of 5 C, it still shows a discharge specific capacity of 615.7 mAh g-1 , showing excellent rate performance. More importantly, the capacity is 258.9 mAh g-1 after 1500 cycles at 5 C, and the attenuation per cycle is only 0.039%, and the Coulomb efficiency remains above 95%.

13.
Hepatology ; 75(2): 438-454, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34580902

RESUMO

BACKGROUND AND AIMS: HBV infection has been reported to trigger endoplasmic reticulum (ER) stress and initiate autophagy. However, how ER stress and autophagy influence HBV production remains elusive. Here, we studied the effect of tunicamycin (TM), an N-glycosylation inhibitor and ER stress inducer, on HBV replication and secretion and examined the underlying mechanisms. APPROACH AND RESULTS: Protein disulfide isomerase (an ER marker), microtubule-associated protein 1 light chain 3 beta (an autophagosome [AP] marker), and sequestosome-1 (a typical cargo for autophagic degradation) expression were tested in liver tissues of patients with chronic HBV infection and hepatoma cell lines. The role of TM treatment in HBV production and trafficking was examined in hepatoma cell lines. TM treatment that mimics HBV infection triggered ER stress and increased AP formation, resulting in enhanced HBV replication and secretion of subviral particles (SVPs) and naked capsids. Additionally, TM reduced the number of early endosomes and HBsAg localization in this compartment, causing HBsAg/SVPs to accumulate in the ER. Thus, TM-induced AP formation serves as an alternative pathway for HBsAg/SVP trafficking. Importantly, TM inhibited AP-lysosome fusion, accompanied by enhanced AP/late endosome (LE)/multivesicular body fusion, to release HBsAg/SVPs through, or along with, exosome release. Notably, TM treatment inhibited HBsAg glycosylation, resulting in impairment of HBV virions' envelopment and secretion, but it was not critical for HBsAg/SVP trafficking in our cell systems. CONCLUSIONS: TM-induced ER stress and autophagic flux promoted HBV replication and the release of SVPs and naked capsids through the AP-LE/MVB axis.


Assuntos
Antivirais/farmacologia , Carcinoma Hepatocelular/metabolismo , Estresse do Retículo Endoplasmático , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/fisiopatologia , Neoplasias Hepáticas/metabolismo , Tunicamicina/farmacologia , Replicação Viral , Autofagossomos/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Capsídeo , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Glicosilação/efeitos dos fármacos , Antígenos de Superfície da Hepatite B/metabolismo , Hepatite B Crônica/metabolismo , Humanos , Lisossomos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Corpos Multivesiculares , Isomerases de Dissulfetos de Proteínas/metabolismo , Proteína Sequestossoma-1/metabolismo , Vírion
14.
Inorg Chem ; 62(27): 10762-10771, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37377386

RESUMO

The successful management and safe disposal of high-level nuclear waste necessitate the efficient separation of actinides (An) from lanthanides (Ln), which has emerged as a crucial prerequisite. Mixed donor ligands incorporating both soft and hard donor atoms have garnered interest in the field of An/Ln separation and purification. One such example is nitrilotriacetamide (NTAamide) derivatives, which have demonstrated selectivity in extracting minor actinide Am(III) ions over Eu(III) ions. Nevertheless, the Am/Eu complexation behavior and selectivity remain underexplored. In the work, a comprehensive and systematic investigation has been conducted for [M(RL)(NO3)3] complexes (M = Am and Eu) utilizing relativistic density functional theory. The NTAamide ligand (RL) is substituted with various alkyl groups, namely, methyl, ethyl, propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl. Thermodynamic calculations show that the alkyl chain length in NTAamide is capable of tuning the separation selectivity of Am and Eu. Moreover, the differences in calculated free energies between Am and Eu complexes are more negative for R = Bu-Oct than Me-Pr. This indicates that elongation of the alkyl chain can increase the efficiency of selective separation of Am(III) from Eu(III). Based on the quantum theory of atoms in molecules and charge decomposition analyses, it has been observed that the strength of Am-RL bonds is higher than that of Eu-RL bonds. This disparity is attributed to a greater degree of covalency in Am-RL bonds and a higher level of charge transfer from ligands to Am within complexes containing these bonds. Energies of occupied orbitals with the central N character are recognized overall lower for [Am(OctL)(NO3)3] than for [Eu(OctL)(NO3)3], indicative of stronger complexation stability of the former. These results offer valuable insights into the separation mechanism of NTAamide ligands, which can help guide the development of more powerful agents for An/Ln separation in future applications.

15.
Inorg Chem ; 62(9): 3916-3928, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36821293

RESUMO

Non-heterocyclic N-donor nitrilotriacetate-derived triamide ligands are one of the most promising extractants for the selective extraction separation of trivalent actinides over lanthanides, but the thermodynamics and mechanism of the complexation of this kind of ligand with actinides and lanthanides are still not clear. In this work, the complexation behaviors of N,N,N',N',N″,N″-hexaethylnitrilotriacetamide (NTAamide(Et)) with four representative trivalent lanthanides (La3+, Nd3+, Eu3+, and Lu3+) were systematically investigated by using 1H nuclear magnetic resonance (1H NMR), ultraviolet-visible (UV-vis) and fluorescence spectrophotometry, microcalorimetry, and single-crystal X-ray diffractometry. 1H NMR spectroscopic titration of La3+ and Lu3+ indicates that two species of 1:2 and 1:1 metal-ligand complexes were formed in NO3- and ClO4- media. The stability constants of NTAamide(Et) with Nd3+ and Eu3+ obtained by UV-vis and fluorescence titration show that the complexing strength of NTAamide(Et) with Nd3+ is lower than that with Eu3+ in the same anionic medium, while that of the same lanthanide complex is higher in ClO4- medium than in NO3- medium. Meanwhile, the formation reactions for all metal-ligand complexes are driven by both enthalpy and entropy. The structures of lanthanide complexes in the single ClO4- and NO3- medium and the mixed one were determined to be [LnL2(MeOH)](ClO4)3 (Ln = La, Nd, Eu, and Lu), [LaL2(EtOH)2][La(NO3)6], and [LaL2(NO3)](ClO4)2, separately. The average bond lengths of lanthanide complexes decrease gradually with the decrease in ionic radii of Ln3+, indicating that heavier lanthanides form stronger complexes due to the lanthanide contraction effect, which coincides with the trend of the complexing strength obtained by spectroscopic titration. This work not only reveals the thermodynamics and mechanism of the complexation between NTAamide ligands and lanthanides but also obtains the periodic tendency of complexation between them, which may facilitate the separation of trivalent lanthanides from actinides.

16.
Pharmacol Res ; 179: 106203, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35381342

RESUMO

More than 100 species of annual herb genus Suaeda widely distribute (Asia, North America, northern Africa and Europe), are rich in resources (about hundreds of millions of tons/Y) and have a long historical application. Most of them are mainly used for traditional food, feed and medicine. Recently, they have been employed to repair saline-alkali land and beautify the environment. So far, only 27 species have been reported on the bioactivity diversity, broad spectrum and effectiveness in clinical practice. Therefore, the in-depth and extensive research of Suaeda has become a research hotspot around the world. However, only one review summarized the nutritional, chemical and biological values of Suaeda. By searching the international authoritative databases (ACS Publications, ScienceDirect, PubMed, Springer, web of Science and Bing International etc.) and collecting 103 literatures closely related to Suaeda (1895-2021), herewith a comprehensive and systematic review was conducted on the phytology, chemistry, pharmacology and clinical application, enveloping the classification evolution between Amaranthaceae and Chenopodiaceae, distribution and common botanical characteristics; involving 9 chemical categories of 163 derivatives covering 14 new and 6 first-isolated ones, and appraising the content determination of 6 categories of components; mainly including the pharmacology of 13 species in vivo and vitro; estimating the clinical application of 16 species cured the related diseases of eight human physiological system except for the motor system. It is expected that this paper will provide forward-looking scientific ideas and literature support for the further modern research, development and utilization of the genus.


Assuntos
Chenopodiaceae , Fitoterapia , Etnofarmacologia , Europa (Continente) , Humanos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
17.
Inorg Chem ; 61(34): 13293-13305, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-35977422

RESUMO

Effective and selective separation and recovery of the fission product palladium from high-level liquid waste are conducive not only to reducing its hazards to the public health and environment but also to alleviate the pressure on the increasing demand for natural palladium. Herein, the Pd2+ extraction in an HNO3 solution with a nitrilotriacetate-derived triamide ligand NTAamide(n-Oct) and the complexation between them were investigated. Using n-octanol as a diluent, NTAamide(n-Oct) demonstrated an excellent selectivity, strong extractability, and high loading capacity for Pd2+ extraction. Combined with the results of single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, electrospray ionization-mass spectroscopy, microcalorimetric titration, and slope analysis, the extracted complexes were determined as [PdL2](NO3)2 and [PdL2][Pd(NO3)4] (where L denotes the NTAamide ligand) in 0.10 and 3.0 mol/L HNO3 solutions, respectively. The extraction model closely depended on the solvation state of Pd2+ in the HNO3 solution. An ion-pair extraction model was proposed and discussed.


Assuntos
Paládio , Cristalografia por Raios X , Indicadores e Reagentes , Ligantes , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Saudi Pharm J ; 30(5): 532-543, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35693441

RESUMO

Folium Artemisiae argyi Carbonisatum (FAAC) is a traditional medicine widely used in clinic. It has the effect of hemostasis by warming meridians. In order to further explore the chemical composition and biological activity of FAAC, the methanol extract of FAAC was isolated and purified by open column and high- performance liquid chromatography. and the complete structure was characterized by nuclear magnetic resonance (NMR) and LREI-MS for the first time, namely rutin, quercetin and octacosanol respectively. Initially the toxic effect of methanol extract of FAAC on zebrafish was evaluated by observing the phenotypic characteristics, spontaneous twitch times, heart rate, hatching rate, the distance of SV-BA and cardiomyocyte apoptosis of zebrafish. The results showed that FAAC has embryonic development toxicity and cardiotoxicity when it was higher than 62.5 µg/mL. Meanwhile, the hemostatic effect of methanol extract of FAAC was compared with FAA (Folium Artemisia argyi) by zebrafish intestinal bleeding model originally. The results showed that the hemostatic effect of the medium and high concentration dose groups (3.0 and 30.0 µg/mL) was enhanced for both FAAC and FAA. This study provided an experimental basis for the clinical application of FAAC.

19.
FASEB J ; 34(11): 14473-14489, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32892442

RESUMO

O-GlcNAcylation is a form of posttranslational modification, and serves various functions, including modulation of location, stability, and activity for the modified proteins. O-linked-N-acetylglucosamine (O-GlcNAc) transferase (OGT) is an essential cellular enzyme that posttranslationally modifies the cellular proteins with O-GlcNAc moiety. Early studies reported that the decreased O-GlcNAcylation regulates cellular autophagy, a process relevant for hepatitis B virus replication (HBV) and assembly. Therefore, we addressed the question how O-GlcNAcylation regulates cellular autophagy and HBV replication. Inhibition of OGT activity with a small molecule inhibitor OSMI-1 or silencing OGT significantly enhanced HBV replication and HBsAg production in hepatoma cells and primary human hepatocytes (PHHs). Western blotting analysis showed that inhibition of O-GlcNAcylation-induced endoplasmic reticulum (ER) stress and cellular autophagy, two processes subsequently leading to enhanced HBV replication. Importantly, the numbers of autophagosomes and the levels of autophagic markers LC3-II and SQSTM1/p62 in hepatoma cells were elevated after inhibition of O-GlcNAcylation. Further analysis revealed that inhibition of O-GlcNAcylation blocked autophagosome-lysosome fusion and thereby prevented autophagic degradation of HBV virions and proteins. Moreover, OSMI-1 further promoted HBV replication by inducing autophagosome formation via inhibiting the O-GlcNAcylation of Akt and mTOR. In conclusion, decreased O-GlcNAcylation enhanced HBV replication through increasing autophagosome formation at multiple levels, including triggering ER-stress, Akt/mTOR inhibition, and blockade of autophagosome-lysosome fusion.


Assuntos
Autofagia , Vírus da Hepatite B/fisiologia , N-Acetilglucosaminiltransferases/metabolismo , Replicação Viral , Autofagossomos/metabolismo , Estresse do Retículo Endoplasmático , Glicosilação , Células Hep G2 , Humanos , Lisossomos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , N-Acetilglucosaminiltransferases/antagonistas & inibidores , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Sequestossoma-1/metabolismo , Serina-Treonina Quinases TOR/metabolismo
20.
Cell Microbiol ; 22(2): e13131, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31746509

RESUMO

A growing consensus indicates that host metabolism plays a vital role in viral infections. Hepatitis B virus (HBV) infection occurs in hepatocytes with active glucose metabolism and may be regulated by cellular metabolism. We addressed the question whether and how glucose regulates HBV replication in hepatocytes. The low glucose concentration at 5 mM significantly promoted HBV replication via enhanced transcription and autophagy when compared with higher glucose concentrations (10 and 25 mM). At low glucose concentration, AMPK activity was increased and led to ULK1 phosphorylation at Ser 555 and LC3-II accumulation. By contrast, the mTOR pathway was activated by high glucose concentrations, resulting in reduced HBV replication. mTOR inhibition by rapamycin reversed negative effects of high glucose concentrations on HBV replication, suggesting that low glucose concentration promotes HBV replication by stimulating the AMPK/mTOR-ULK1-autophagy axis. Consistently, we found that glucose transporters inhibition using phloretin also enhanced HBV replication via increased AMPK/mTOR-ULK1-induced autophagy. Surprisingly, the glucose analogue 2-deoxy-D-glucose reduced HBV replication through activating the Akt/mTOR signalling pathway also at the low glucose concentrations. Our study reveals that glucose is an important factor for the HBV life cycle by regulating HBV transcription and posttranscriptional steps of HBV replication via cellular autophagy.


Assuntos
Autofagia , Glucose/metabolismo , Vírus da Hepatite B/fisiologia , Hepatite B/virologia , Replicação Viral , Quinases Proteína-Quinases Ativadas por AMP , Células Hep G2 , Humanos , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
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