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1.
Small ; : e2401044, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38516941

RESUMO

Atomically precise metal clusters serve as a unique model for unraveling the intricate mechanism of the catalytic reaction and exploring the complex relationship between structure and activity. Herein, three series of water-soluble heterometallic clusters LnCu6, abbreviated as LnCu6-AC (Ln = La, Nd, Gd, Er, Yb; HAC = acetic acid), LnCu6-IM (Ln = La and Nd; IM = Imidazole), and LnCu6-IDA (Ln = Nd; H2IDA = Iminodiacetic acid) are presented, each featuring a uniform metallic core stabilized by distinct protected ligands. Crystal structure analysis reveals a triangular prism topology formed by six Cu2+ ions around one Ln3+ ion in LnCu6, with variations in Cu···Cu distances attributed to different ligands. Electrocatalytic oxygen evolution reaction (OER) shows that these different LnCu6 clusters exhibit different OER activities with remarkable turnover frequency of 135 s-1 for NdCu6-AC, 79 s-1 for NdCu6-IM and 32 s-1 for NdCu6-IDA. Structural analysis and Density Functional Theory (DFT) calculations underscore the correlation between shorter Cu···Cu distances and improves OER catalytic activity, emphasizing the pivotal role of active-site distance in regulating electrocatalytic OER activities. These results provide valuable insights into the OER mechanism and contribute to the design of efficient homogeneous OER electrocatalysts.

2.
Angew Chem Int Ed Engl ; 62(7): e202217926, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36484495

RESUMO

This work reports the interesting and unique cation-exchange behaviors of the first indium-bridged purely inorganic 3D framework based on high-nuclearity polyoxoniobates as building units. Each nanoscale polyoxoniobate features a fascinating near-icosahedral core-shell structure with six pairs of unique inorganic "molecular tweezers" that have changeable openings for binding different metal cations via ion-exchanges and exhibit unusual selective metal-uptake behaviors. Further, the material has high chemical stability so that can undergo single-crystal-to-single-crystal metal-exchange processes to produce a dozen new crystals with high crystallinity. Based on these crystals and time-dependent metal-exchange experiments, we can visually reveal the detailed metal-exchange interactions and mechanisms of the material at the atomic precision level. This work demonstrates a rare systematic and atomic-level study on the ion-exchange properties of nanoclusters, which is of significance for the exploration of cluster-based ion-exchange materials that are still to be developed.

3.
J Biol Chem ; 295(1): 83-98, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31690627

RESUMO

Adipose tissue is essential for whole-body glucose homeostasis, with a primary role in lipid storage. It has been previously observed that lactate production is also an important metabolic feature of adipocytes, but its relationship to adipose and whole-body glucose disposal remains unclear. Therefore, using a combination of metabolic labeling techniques, here we closely examined lactate production of cultured and primary mammalian adipocytes. Insulin treatment increased glucose uptake and conversion to lactate, with the latter responding more to insulin than did other metabolic fates of glucose. However, lactate production did not just serve as a mechanism to dispose of excess glucose, because we also observed that lactate production in adipocytes did not solely depend on glucose availability and even occurred independently of glucose metabolism. This suggests that lactate production is prioritized in adipocytes. Furthermore, knocking down lactate dehydrogenase specifically in the fat body of Drosophila flies lowered circulating lactate and improved whole-body glucose disposal. These results emphasize that lactate production is an additional metabolic role of adipose tissue beyond lipid storage and release.


Assuntos
Adipócitos/metabolismo , Homeostase , Ácido Láctico/biossíntese , Células 3T3 , Animais , Células Cultivadas , Drosophila , Corpo Adiposo/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Ácido Láctico/metabolismo , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley
4.
Inorg Chem ; 60(9): 6162-6166, 2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33871999

RESUMO

A tetratellurium-substituted heteropolyoxoniobate with the formula K2H[Cu(phen)(H2O)]4[Cu(phen)]2[(LiNb8Te4O40)]·34H2O (1; phen = 1,10-phenanthroline) was hydrothermally prepared and structurally characterized. The compound represents the first hexavalent tellurium-substituted Keggin-type polyoxometalate (POM) so far. What is more, the POM cluster in 1 can elaborately self-assemble into a stable supramolecular framework with an ion conduction property through unique intermolecular π-π stacking.

5.
J Org Chem ; 83(8): 4762-4768, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29618207

RESUMO

Allylic sulfones were synthesized with excellent selectivity and good yield via Pd-catalyzed cross-coupling of vinyl iodide with N-tosylhydrazone. This process involves palladium carbene migratory insertion/trapping with sulfinic acid salts. For the previous Pd-catalyzed N-tosylhydrazone cross-coupling, sulfinic acid salt is generated as a byproduct. In this transformation, the diazo compound and the sulfinic acid salt, which are all generated from N-tosylhydrazone, were used as cross-coupling partner.

6.
J Org Chem ; 82(4): 2205-2210, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28103439

RESUMO

A tandem Michael-Henry reaction of 2-mercaptoquinoline-3-carbaldehydes with nitroolefins using hydrogen-bonding-based cooperative organocatalysts for the highly diastereodivergent synthesis of chiral functionalized 3,4-dihydro-2H-thiopyrano[2,3-b]quinolines with three contiguous tertiary stereocenters has been developed.

7.
J Org Chem ; 81(1): 66-76, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26642246

RESUMO

An iodine-promoted one-pot radical cyclization reaction of 1,6-enynes with sulfonyl hydrazides to provide five-membered and hexatomic ring sulfonylated products under the same conditions is established. This reaction proceeded smoothly in water and gave the corresponding products by using I2/TBHP instead of expensive and toxic catalysts with C-S and C-I bond formed in one step. This method also allowed easy access to significant functional sulfones for potential applications in medicinal and organic chemistry.

8.
Chemistry ; 20(20): 5910-3, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24729510

RESUMO

A convenient zinc-promoted [4+3] cycloaddition of a carbonyl ene-yne with simple dienes was first achieved. This reaction provided an efficient strategy to prepare various cyclohepta[b]furan rings by cascade cycloadditions. Additionally, a multicomponent reaction of dione, alkynal, and diene was also reported, which exhibited a novel strategy for selective creations of C-O bonds and C-C bonds.


Assuntos
Furanos/síntese química , Compostos Heterocíclicos/síntese química , Zinco/química , Catálise , Reação de Cicloadição , Furanos/química , Compostos Heterocíclicos/química
9.
Chemistry ; 20(22): 6745-51, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24771707

RESUMO

A straightforward method for the synthesis of highly functionalized vinylarenes through palladium-catalyzed, norbornene-mediated C-H activation/carbene migratory insertion is described. Extension to a one-pot procedure is also developed. Furthermore, this method can also be used to generate polysubstituted bicyclic molecules. The reaction proceeds under mild conditions to give the products in satisfactory yields using readily available starting materials. This is a Catellani-Lautens reaction that incorporates different types of coupling partners. Additionally, this reaction is the first to demonstrate the possibility of combining Pd-catalyzed insertion of diazo compounds and Pd-catalyzed C-H activation.

10.
Chemistry ; 20(49): 16093-6, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25339137

RESUMO

Without extra addition of sulfinate salt, allylic sulfones were synthesized by palladium-catalyzed cross-coupling of aryl iodide with N-tosylhydrazone. In this transformation, not only the diazo compound but also the sulfinate salt, which were both generated in situ from base-mediated decomposition of the N-tosylhydrazone, was used as nucleophilic partner.


Assuntos
Compostos Alílicos/síntese química , Hidrazonas/química , Paládio/química , Sulfonas/síntese química , Compostos de Tosil/química , Compostos Alílicos/química , Catálise , Sulfonas/química
11.
J Org Chem ; 79(14): 6627-33, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24988133

RESUMO

ortho-Aminated vinylarene derivatives were obtained via a reaction of aryl iodides, N-benzoyloxyamines, and N-tosylhydrazones. This approach involves a palladium-catalyzed, norbornene-mediated ortho-amination/N-tosylhydrazone insertion reaction. In this transformation, one C-N bond and one C-C bond are formed and an amine group is introduced at the ortho position successfully.

12.
Front Pharmacol ; 15: 1377876, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567357

RESUMO

Introduction: Acori Tatarinowii Rhizoma (ATR) is a well-known traditional Chinese medicine that is used for treating neuropathic diseases. However, there is little information about the safety of ATR. Methods: The present study evaluated the acute and subacute oral toxicity of a water extract of ATR in Institute of Cancer Research (ICR) mice. In acute trials, a single administration of extract at a dose 5,000 mg/kg body weight led to no clinical signs of toxicity or mortality, indicating that the lethal dose (LD50) exceeded 5,000 mg/kg. A subacute toxicity test was done using daily doses of 1,250, 2,500, and 5,000 mg/kg of the ATR extract for 28 days, which did not show any adverse clinical symptoms or mortality. However, the male renal organ index and urea level in mice given 5,000 mg/kg was obviously abnormal, which was consistent with pathological results and suggested that this dose might cause kidney injury. Results: Doses of ATR lower than 2,500 mg/kg could be regarded as safe, although the potential cumulative effects of long-term use of high doses of ATR need to be considered. Discussion: The study highlights the function of ATR in reducing blood lipids and provides a new idea for its widespread clinical use in the future.

13.
PLoS One ; 19(3): e0300935, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517844

RESUMO

OBJECTIVE: This study aims to investigate the relationship between taste dysfunction and depression among patients with schizophrenia, to achieve early detection of depression in clinical practice. METHODS: Following PRISMA guidance, a comprehensive literature search was conducted globally, covering papers published from 1961 to June 2023. A total of 17 manuscripts were selected through meta-analysis and sensitivity analysis after examining available materials from seven databases to determine the correlation between depression and taste dysfunction. RESULTS: The comparison of the 17 selected manuscripts revealed that individuals with gustatory dysfunction may be more likely to experience depressive symptoms (SMD, 0.51, 95% CI, 0.08 to 0.93, p = 0.02). Depression is associated with taste dysfunction in certain aspects, as indicated by the pleasantness ratings of sucrose solutions (SMD, -0.53, 95% confidence interval [CI] -1.11 to 0.05, p = 0.08), gustatory identification ability (SMD, 0.96, 95% CI, 0.03 to 1.89, p = 0.04), and the perception threshold of sweet taste (MD, 0.80, 95% CI, 0.79 to 0.81, p < 0.00001). CONCLUSIONS: Due to variations in the methods, designs, and selection criteria employed in the included studies, it is necessary to establish a feasible framework. Future research using detailed and targeted approaches can provide clearer and more unified conclusions on the relationship between taste dysfunction and depression. Moreover, further high-quality research is needed to obtain clearer conclusions and explore the potential of taste dysfunction as an effective tool for early screening of depression. TRIAL REGISTRATION: This review has been registered in the PROSPERO on April 2022 with the identifier CRD42023400172.


Assuntos
Depressão , Esquizofrenia , Humanos , Depressão/diagnóstico , Depressão/prevenção & controle , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Sacarose , Distúrbios do Paladar , Sensação
14.
Behav Brain Res ; 465: 114968, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38521360

RESUMO

PURPOSE: Depression is a psychiatric disorder and the treatment of depression is an urgent problem that need to be solved. Gastrodin (GAS) is a Traditional Chinese Medicine from an orchid and is used for neurological diseases, including depressive disorders. METHODS: To assess the effect of GAS on gut microbiota of depressive mice, we established a chronic unpredictable mild stress (CUMS)-induced mouse model, and GAS was administered to one group of the mice. Animal behavior experiments were used to detect depressive-like behaviors, and 16 S rRNA gene analysis was applied to detect the gut microbiota of each group. All raw sequences were deposited in the NCBI Sequence Read Archive under accession number SRP491061. RESULTS: GAS treatment significantly improved depressive-like behaviors as well as the diversity and abundance of the gut microbiota. The depressive-like behaviors of the CUMS-GAS group were improved in different degrees compared with the CUMS group. The linear discriminant analysis (LDA) of the gut microbiota showed that the makeup of the gut microbiota in mice changed dramatically in the CUMS-GAS group, compared with the CUMS group, Bacteroides (LDA = 3.94, P < 0.05) were enriched in the CUMS-GAS group at the genus level. In comparison to the CUMS group, the CUMS-GAS group had a greater concentration numbers of Lactobacillus, Corynebacterium, Staphylococcus, Bacteroides, Psychrobacter, and Alistipes. CONCLUSION: Our results suggested that GAS improved depressive-like behaviors in mice and impacted the microbial composition of the gut. Our research indicated that dysbiosis of the gut microbiota may be affected by GAS treatment, which improved depressive-like behaviors in the CUMS-induced mouse model of depression.


Assuntos
Álcoois Benzílicos , Depressão , Microbioma Gastrointestinal , Glucosídeos , Humanos , Camundongos , Animais , Depressão/tratamento farmacológico , Depressão/psicologia , Comportamento Animal , Estresse Psicológico/complicações
15.
Artigo em Inglês | MEDLINE | ID: mdl-38778616

RESUMO

BACKGROUND: Epilepsy is a serious neurological disorder that affects millions of people each year, often leading to cognitive issues and reduced quality of life. Medication is the main treatment, but many patients experience negative side effects. Male Sprague-Dawley (SD) rats were chosen as experimental animals for this experiment due to their physiological and genetic similarities to humans, cost-effectiveness, and ease of handling in a laboratory setting. AIMS: The objective of this study was to assess the neuroprotective properties of baicalin (BA) in relation to its impact on anxiety and depressive-like behaviors in the epilepsy model. METHODS: Thirty male Sprague-Dawley (SD) rats were selected for this experiment. Pentylenetetrazol (PTZ) kindling (40 mg/kg; i.p.) was utilized to establish an epilepsy model. The effect of BA (50 mg/kg; gavage) on seizure severity (assessed using the Racine scale), anxiety, and depressive- like behaviors (evaluated through open field experiments and forced swimming tests) was examined. Histological examinations, including hematoxylin and eosin (HE) staining and Nissl staining, were conducted to assess neuronal damage. Furthermore, the neuroprotective properties of BA were examined through the analysis of Doublecortin (DCX), MKI67 (KI67), and Brain-Derived Neurotrophic Factor (BDNF) levels in the hippocampus of rats. The inhibitory impact of BA on neuroinflammation was assessed via dual labeling for NOD-like receptor thermal protein domain associated protein 3 (NLRP3) and the microglial marker ionized calcium- binding adapter molecule 1 (Iba-1). The influence of BA on the expression of P2X7 receptor (P2X7R), NLRP3, and Interleukin-1ß (IL-1ß) was also assessed by reverse transcription quantitative PCR (RT-qPCR) in the brain. Finally, we employed a molecular docking model to assess the extent of receptor-ligand binding. RESULTS: Epilepsy models exhibited significant anxiety and depressive-like behaviors, and BA significantly reduced the severity of seizures in these rats while also alleviating their anxiety and depressive-like behaviors. Moreover, neuronal loss and damage were observed in the hippocampus of epileptic rats, but BA was able to effectively counteract this issue by enhancing BDNF expression and promoting neurogenesis within the hippocampus, especially in the DG region. The co-localization of Iba-1 with NLRP3 indicated the activation of NLRP3 inflammasome in microglia. Subsequent RT-PCR revealed that BA may alleviate anxiety and depressive-like behaviors in epileptic rats by activating the P2RX7/NLRP3/ IL-1ß signaling pathway. The final molecular docking results indicated that BA had a good binding affinity with proteins, such as P2RX7, NLRP3, and IL-1ß. CONCLUSION: This study confirmed the effectiveness of BA in improving anxiety and depressivelike behaviors associated with epilepsy. Moreover, it provides theoretical support for the neuroprotective role demonstrated by BA.

16.
Dalton Trans ; 53(17): 7424-7429, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38591126

RESUMO

A 3D tellurium-substituted heteropolyoxoniobate framework H5K3Na[Cu(en)2]2[Cu(en)0.75(H2O)2.5]{[(Te2Nb19O58)(µ3-OH)2]}·24H2O (1, en = ethylenediamine) with a 6-connected pcu topology is built from heart-shaped {Te2Nb19O60} clusters and copper complexes. The {Te2Nb19O60} cluster represents the new tellurniobate structure type with a 19-nuclearity Nb cluster. It consists of two new monovacant Lindqvist {Nb5O19} clusters, one boat-shaped {Nb9O32} cluster and two TeO32- anions. The {Te2Nb19O60} polyanions are interlinked by [Cu(en)2]2+ complexes into a 2D (4, 4) grid-like layer containing rhombic sheets. The Cu2+ supports the adjacent layers through Te-O-Cu-O-Te- bonds to form a three-dimensional heteropolyoxoniobate framework with 1D channels. This compound exhibits good chemical and solvent stability and proton conductivity, with a conductivity of 7.9 × 10-3 S cm-1 at 85 °C under 98% RH.

17.
PLoS One ; 17(12): e0278907, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36520790

RESUMO

OBJECTIVE: This study offers meta-analytic data on the potential association between epilepsy and depression especially for the prevalence of depression in epilepsy or vice versa. METHODS: The relevant studies were searched and identified from nine electronic databases. Studies that mentioned the prevalence and/or incidence of epilepsy and depression were included. Hand searches were also included. The search language was English and the search time was through May 2022. Where feasible, random-effects models were used to generate pooled estimates. RESULTS: After screening electronic databases and other resources, 48 studies from 6,234 citations were included in this meta-analysis. The period prevalence of epilepsy ranged from 1% to 6% in patients with depression. In population-based settings, the pooled period prevalence of depression in patients with epilepsy was 27% (95% CI, 23-31) and 34% in clinical settings (95% CI, 30-39). Twenty studies reported that seizure frequency, low income, unemployment of the patients, perception of stigma, anxiety, being female, unmarried status, disease course, worse quality of life, higher disability scores, and focal-impaired awareness seizures were risk factors for depression. CONCLUSION: Our study found that epilepsy was associated with an increased risk of depression. Depression was associated with the severity of epilepsy.


Assuntos
Epilepsias Parciais , Epilepsia , Humanos , Feminino , Masculino , Depressão/complicações , Depressão/epidemiologia , Qualidade de Vida , Epilepsia/complicações , Epilepsia/epidemiologia , Convulsões/complicações
18.
J Mol Cell Biol ; 14(1)2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-34893854

RESUMO

Spinal cord impairment involving motor neuron degeneration and demyelination can cause lifelong disabilities, but effective clinical interventions for restoring neurological functions have yet to be developed. In early spinal cord development, neural progenitors of the motor neuron (pMN) domain, defined by the expression of oligodendrocyte transcription factor 2 (OLIG2), in the ventral spinal cord first generate motor neurons and then switch the fate to produce myelin-forming oligodendrocytes. Given their differentiation potential, pMN progenitors could be a valuable cell source for cell therapy in relevant neurological conditions such as spinal cord injury. However, fast generation and expansion of pMN progenitors in vitro while conserving their differentiation potential has so far been technically challenging. In this study, based on chemical screening, we have developed a new recipe for efficient induction of pMN progenitors from human embryonic stem cells. More importantly, these OLIG2+ pMN progenitors can be stably maintained for multiple passages without losing their ability to produce spinal motor neurons and oligodendrocytes rapidly. Our results suggest that these self-renewing pMN progenitors could potentially be useful as a renewable source of cell transplants for spinal cord injury and demyelinating disorders.


Assuntos
Autorrenovação Celular , Células-Tronco Embrionárias Humanas , Traumatismos da Medula Espinal , Diferenciação Celular/fisiologia , Humanos , Neurônios Motores/metabolismo , Oligodendroglia , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/terapia
19.
Cell Signal ; 77: 109812, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33164880

RESUMO

It has been widely reported that exosomes derived from mesenchymal stem cells (MSCs) have a protective effect on myocardial infarction (MI). However, the specific molecules which play a damaging role in MSCs shuttled miRNAs are much less explored. MiRNA-153-3p (miR-153-3p) is a vital miRNA which has been proved to modulate cell proliferation, apoptosis, angiogenesis, peritoneal fibrosis and aortic calcification. Here, we aim to study the effect and mechanism of miR-153-3p in MSC-derived exosomes on hypoxia-induced myocardial and microvascular damage. The exosomes of MSCs were isolated and identified, and the MSCs-exosomes with low expression of miR-153-3p (exo-miR-153-3p-) were constructed to interfere with the endothelial cells and cardiomyocytes in the oxygen-glucose deprivation (OGD) model. The viability, apoptosis, angiogenesis of endothelial cells and cardiomyocytes were determined. Additionally, ANGPT1/VEGF/VEGFR2/PI3K/Akt/eNOS pathway was detected by ELISA and/or western blot. The results illustrated that exo-miR-153-3p- significantly reduced the apoptosis of endothelial cells and cardiomyocytes and promoted their viability. Meanwhile, exo-miR-153-3p- can promote the angiogenesis of endothelial cells. Mechanistically, miR-153-3p regulates the VEGF/VEGFR2/PI3K/Akt/eNOS pathways by targeting ANGPT1. Intervention with VEGFR2 inhibitor (SU1498, 1 µM) remarkably reversed the protective effect of exo-miR-153-3p- in vascular endothelial cells and cardiomyocytes treated by OGD. Collectively, MSCs-derived exosomes with low-expressed miR-153-3p notably promotes the activation of ANGPT1 and the VEGF/VEGFR2 /PI3K/Akt/eNOS pathways, thereby preventing the damages endothelial cells and cardiomyocytes against hypoxia.


Assuntos
Angiopoietina-1/metabolismo , Exossomos/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais , Angiopoietina-1/química , Angiopoietina-1/genética , Animais , Antagomirs/metabolismo , Apoptose , Hipóxia Celular , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Org Lett ; 23(12): 4920-4924, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34085517

RESUMO

A palladium-catalyzed C-H allylation of electron-deficient polyfluoroarenes with gem-difluorinated cyclopropanes is reported. It provides a useful and facile approach to 2-fluoroallylic polyfluoroarenes in moderate to excellent yields with high Z-selectivity. In addition, this new approach has good functional group compatibility and broad substrate scope.

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