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1.
J Am Chem Soc ; 146(6): 4068-4077, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38289263

RESUMO

The synthesis of photocatalysts with both broad light absorption and efficient charge separation is significant for a high solar energy conversion, which still remains to be a challenge. Herein, a narrow-bandgap Y2Ti2O5S2 (YTOS) oxysulfide nanosheet coexposed with defined {101} and {001} facets synthesized by a flux-assisted solid-state reaction was revealed to display the character of an anisotropic charge migration. The selective photodeposition of cocatalysts demonstrated that the {101} and {001} surfaces of YTOS nanosheets were the reduction and oxidation regions during photocatalysis, respectively. Density functional theory (DFT) calculations indicated a band energy level difference between the {101} and {001} facets of YTOS, which contributes to the anisotropic charge migration between them. The exposed Ti atoms on the {101} surface and S atoms on the {001} surface were identified, respectively, as reducing and oxidizing centers of YTOS nanosheets. This anisotropic charge migration generated a built-in electric field between these two facets, quantified by spatially resolved surface photovoltage microscopy, the intensity of which was found to be highly correlated with photocatalytic H2 production activity of YTOS, especially exhibiting a high apparent quantum yield of 18.2% (420 nm) after on-site modification of a Pt@Au cocatalyst assisted by Na2S-Na2SO3 hole scavengers. In conjunction with an oxygen-production photocatalyst and a [Co(bpy)3]2+/3+ redox shuttle, the YTOS nanosheets achieved a solar-to-hydrogen conversion efficiency of 0.15% via a Z-scheme overall water splitting. Our work is the first to confirm anisotropic charge migration in a perovskite oxysulfide photocatalyst, which is crucial for enhancing charge separation and surface catalytic efficiency in this material.

2.
Angew Chem Int Ed Engl ; 63(8): e202316029, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38168107

RESUMO

RuO2 is one of the benchmark electrocatalysts used as the anode material in proton exchange membrane water electrolyser. However, its long-term stability is compromised due to the participation of lattice oxygen and metal dissolution during oxygen evolution reaction (OER). In this work, weakened covalency of Ru-O bond was tailored by introducing tensile strain to RuO6 octahedrons in a binary Ru-Sn oxide matrix, prohibiting the participation of lattice oxygen and the dissolution of Ru, thereby significantly improving the long-term stability. Moreover, the tensile strain also optimized the adsorption energy of intermediates and boosted the OER activity. Remarkably, the RuSnOx electrocatalyst exhibited excellent OER activity in 0.1 M HClO4 and required merely 184 mV overpotential at a current density of 10 mA cm-2 . Moreover, it delivered a current density of 10 mA cm-2 for at least 150 h with negligible potential increase. This work exemplifies an effective strategy for engineering Ru-based catalysts with extraordinary performance toward water splitting.

3.
Chemistry ; 28(51): e202201169, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-35688798

RESUMO

Photoelectrochemical (PEC) performance of WO3 photoanodes for water splitting is heavily influenced by the orientation of crystal facets. In this work, mono-particle-layer electrodes, assembled by particulate WO3 square plates with highly uniform alignment along the (002) facet, improved PEC water oxidation kinetics and stability. Photo-deposition of Au along the cracks formed on the surface of the plates, which are the edges of {110} facets, was found to further enhance electron collection efficiency. Combination of these two strategies allowed the facet-engineered WO3 electrode to produce significantly higher efficiencies in charge separation and transfer than the electrode prepared without facet orientation. This work has provided a facile route for fabricating a structurally designed WO3 photoelectrode, which is also applicable to other regularly shaped semiconductor photocatalysts with anisotropic charge migration.

4.
Zhongguo Zhong Yao Za Zhi ; 43(14): 2935-2943, 2018 Jul.
Artigo em Zh | MEDLINE | ID: mdl-30111052

RESUMO

Polygonatum is a genus of the perennial herb family Liliaceae, with great potential in food, medicine and other field. In this study, genetic diversity and cluster structure analysis of 6 species in Polygonatum were investigated the molecular marker technique of simple sequence repeat (SSR). A total of 49 SSR makers were used to study genetic diversity and population structure within 60 germplasm resources which obtained from 38 counties and cities in 14 provinces of China. A total of 211 alleles were identified and the number of alleles ranged from 2 to 10, with an average of 4.306 1 alleles per SSR. The range of polymorphism information content (PIC) varied from 0.731 8 to 0.031 7, with the average of 0.309 6. The cluster analysis classified 60 germplasm resources into four defined groups at the genetic distance value of 0.26, among which most species with relatives were clustered into the same group. Extraordinarily, there were 6 germplasm resources clustered into other species, indicating that the classification of inter-genus and geographical distribution was crossed in Polygonatum. The genetic diversity index of the 4 geographical populations from high to low was: Western region, Central China, Southern China, Eastern China. The population structure analysis, also indicating divided the entire collection into four groups, which was similar to the assignment pattern of cluster structure analysis. These results suggested that the Polygonatum germplasm resources used in this study is rich in relatively high genetic diversity with large variation range, relatively fuzzy boundaries of species. It appeared the phenomenon that there is a difference decreases between the alternate leaf system and the rotation leaf system. The genetic diversity in the western region was higher than that in other regions, and the western region may be the origin center of the genus Polygonatum.


Assuntos
Polygonatum , Alelos , China , Variação Genética , Repetições de Microssatélites , Filogenia , Polimorfismo Genético
5.
Nat Chem Biol ; 10(9): 753-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25108821

RESUMO

Phosphatidylinositol bisphosphate (PIP2) regulates the activities of many membrane proteins, including ion channels, through direct interactions. However, the affinity of PIP2 is so high for some channel proteins that its physiological role as a modulator has been questioned. Here we show that PIP2 is a key cofactor for activation of small conductance Ca2+-activated potassium channels (SKs) by Ca(2+)-bound calmodulin (CaM). Removal of the endogenous PIP2 inhibits SKs. The PIP2-binding site resides at the interface of CaM and the SK C terminus. We further demonstrate that the affinity of PIP2 for its target proteins can be regulated by cellular signaling. Phosphorylation of CaM T79, located adjacent to the PIP2-binding site, by casein kinase 2 reduces the affinity of PIP2 for the CaM-SK channel complex by altering the dynamic interactions among amino acid residues surrounding the PIP2-binding site. This effect of CaM phosphorylation promotes greater channel inhibition by G protein-mediated hydrolysis of PIP2.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Fosfatos de Fosfatidilinositol/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Baixa/antagonistas & inibidores , Acetilcolina/farmacologia , Aminoácidos/metabolismo , Sítios de Ligação , Caseína Quinase II/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/farmacologia , Células HEK293 , Humanos , Modelos Moleculares , Fosfatos de Fosfatidilinositol/fisiologia , Fosforilação , Conformação Proteica , Proteína Quinase C/metabolismo
6.
Proc Natl Acad Sci U S A ; 110(12): 4828-33, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23487779

RESUMO

Most proteins, such as ion channels, form well-organized 3D structures to carry out their specific functions. A typical voltage-gated potassium channel subunit has six transmembrane segments (S1-S6) to form the voltage-sensing domain and the pore domain. Conformational changes of these domains result in opening of the channel pore. Intrinsically disordered (ID) proteins/peptides are considered equally important for the protein functions. However, it is difficult to explore the structural features underlying the functions of ID proteins/peptides by conventional methods, such as X-ray crystallography, because of the flexibility of their secondary structures. Unlike voltage-gated potassium channels, families of small- and intermediate-conductance Ca(2+)-activated potassium (SK/IK) channels with important roles in regulating membrane excitability are activated exclusively by Ca(2+)-bound calmodulin (CaM). Upon binding of Ca(2+) to CaM, a 2 × 2 structure forms between CaM and the CaM-binding domain. A channel fragment that connects S6 and the CaM-binding domain is not visible in the protein crystal structure, suggesting that this fragment is an ID fragment. Here we show that the conformation of the ID fragment in SK channels becomes readily identifiable in the presence of NS309, the most potent compound that potentiates the channel activities. This well-defined conformation of the ID fragment, stabilized by NS309, increases the channel open probability at a given Ca(2+) concentration. Our results demonstrate that the ID fragment, itself a target for drugs modulating SK channel activities, plays a unique role in coupling Ca(2+) sensing by CaM and mechanical opening of SK channels.


Assuntos
Cálcio/química , Calmodulina/química , Ativação do Canal Iônico/fisiologia , Peptídeos/química , Canais de Potássio Ativados por Cálcio de Condutância Baixa/química , Animais , Cálcio/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Cristalografia por Raios X , Indóis/química , Oximas/química , Peptídeos/genética , Peptídeos/metabolismo , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Ratos , Canais de Potássio Ativados por Cálcio de Condutância Baixa/genética , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Relação Estrutura-Atividade
7.
J Exp Bot ; 66(20): 6205-18, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26188204

RESUMO

The glucosinolate biosynthetic gene AOP2 encodes an enzyme that plays a crucial role in catalysing the conversion of beneficial glucosinolates into anti-nutritional ones. In Brassica rapa, three copies of BrAOP2 have been identified, but their function in establishing the glucosinolate content of B. rapa is poorly understood. Here, we used phylogenetic and gene structure analyses to show that BrAOP2 proteins have evolved via a duplication process retaining two highly conserved domains at the N-terminal and C-terminal regions, while the middle part has experienced structural divergence. Heterologous expression and in vitro enzyme assays and Arabidopsis mutant complementation studies showed that all three BrAOP2 genes encode functional BrAOP2 proteins that convert the precursor methylsulfinyl alkyl glucosinolate to the alkenyl form. Site-directed mutagenesis showed that His356, Asp310, and Arg376 residues are required for the catalytic activity of one of the BrAOP2 proteins (BrAOP2.1). Promoter-ß-glucuronidase lines revealed that the BrAOP2.3 gene displayed an overlapping but distinct tissue- and cell-specific expression profile compared with that of the BrAOP2.1 and BrAOP2.2 genes. Quantitative real-time reverse transcription-PCR assays demonstrated that BrAOP2.1 showed a slightly different pattern of expression in below-ground tissue at the seedling stage and in the silique at the reproductive stage compared with BrAOP2.2 and BrAOP2.3 genes in B. rapa. Taken together, our results revealed that all three BrAOP2 paralogues are active in B. rapa but have functionally diverged.


Assuntos
Brassica rapa/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Poliploidia , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Brassica rapa/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo
8.
BMC Psychol ; 12(1): 59, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317179

RESUMO

BACKGROUND: Attention Deficit/Hyperactivity Disorder (ADHD) poses cognitive and emotional challenges for Chinese children. This study addresses the potential benefits of Working Memory Training for ADHD-affected children. Understanding its impact on Attention, cognitive regulation, and emotional responses is crucial for tailored interventions in the Chinese context. The Trial Registration Number (TRN) for this study is [TRN-2023-123,456], and it was officially registered on July 15, 2023, by Changchun Normal University. OBJECTIVES: This study investigated how Working Memory training influences Attention, adaptive cognitive regulation, and non-adaptive cognitive emotion regulation in Chinese children with ADHD. It also assessed changes in attentional focus, improvements in adaptive cognitive regulation, and alterations in non-adaptive cognitive emotion regulation strategies. METHODOLOGY: This quasi-experimental study aimed to assess the impact of working memory training on Chinese children with ADHD. Using pretest-posttest measures, 120 female students underwent Cogmed software training, targeting attention deficits and cognitive emotion regulation. Three reliable instruments measured outcomes. The procedure involved informed consent, questionnaires, 25 training sessions, and a two-month follow-up. Statistical analyses, including repeated measures ANOVA, assessed training effects. RESULTS: ANOVA revealed a significant impact of Working memory training on attention deficit. Repeated measures ANOVA for cognitive emotion regulation indicated positive changes in adaptive and non-adaptive strategies over time, with sustained improvements in self-blame, rumination, catastrophizing, and blaming others. Bonferroni follow-up tests showed significant differences between pre-test, post-test, and follow-up, favoring the post-test and follow-up tests. CONCLUSIONS: In summary, this research sheds light on the positive impact of memory training on Attention and cognitive emotion regulation in children with ADHD. The study underscores the potential of working memory interventions, particularly software-focused approaches, in enhancing attention levels and improving cognitive emotion regulation. The findings align with existing literature emphasizing the role of working memory deficits in ADHD. IMPLICATIONS: Practically, incorporating memory training interventions into educational settings emerges as a viable strategy to support children with ADHD. This includes integrating memory training programs into both classroom activities and home-based interventions. Additionally, sustained implementation and long-term follow-up assessments are crucial for maximizing the effectiveness of memory training interventions. Tailoring interventions to specific ADHD subtypes and seamlessly integrating memory training activities into daily routines offer practical and personalized solutions for managing ADHD symptoms in diverse settings.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Regulação Emocional , Criança , Humanos , Feminino , Memória de Curto Prazo/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Treino Cognitivo , Cognição
9.
Small Methods ; : e2301431, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38169117

RESUMO

The intra-gap states that are introduced into a semiconducting photocatalyst via dopants and other defects have significant implications on the transport dynamics of photoexcited electrons and holes during an aqueous light-driven reaction. In this work, mechanistic understanding of Rh-doped rutile, a promising photocatalyst for hydrogen production from water, is gained by systematic assessment combining intensity-modulated photocurrent spectroscopy with sub-gap excitations and alternating-current photocurrent spectroscopy. These operando techniques not only help in discovering a new electronic transport path in Rh-rutile via surface Rh4+ species and elucidating complex interaction between electrolyte molecules and semiconductors, but also underscore the potential of utilizing multiple sub-gap excitations synergistically. This combination offers a powerful tool for acquiring insight into photo-physical and photo-chemical behaviors of photo(electro)catalysts with intra-gap states.

10.
J Phys Chem Lett ; 15(23): 6166-6173, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38836599

RESUMO

Developing an efficient and stable photocathode material for photoelectrochemical solar water splitting remains challenging. Herein, we demonstrate the potential of rutile TiO2 as a photocathode by Rh doping with visible light absorption up to 640 nm and an onset potential of 0.9 V versus the reversible hydrogen electrode. The dopant transforms the rutile host from an n-type semiconductor to a p-type one, as confirmed by the Mott-Schottky curve and kelvin probe force microscopy. Physical and photoelectrochemical analyses further suggest that the doping mechanism is dependent on concentration. Lower levels of dopants generate localized Rh3+, while higher levels favor Rh4+ that interacts more strongly with the O 2p orbitals. The latter is found not only to extend the visible light absorption range but also to facilitate charge transport. This work elucidates the role of the Rh dopant in adjusting the photoelectrochemical behavior of TiO2, and it provides a promising photocathode material for solar energy conversion.

11.
Adv Sci (Weinh) ; : e2402450, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38952061

RESUMO

Discovering new treatments for melanoma will benefit human health. The mechanism by which deoxyhypusine synthase (DHPS) promotes melanoma development remains elucidated. Multi-omics studies have revealed that DHPS regulates m6A modification and maintains mRNA stability in melanoma cells. Mechanistically, DHPS activates the hypusination of eukaryotic translation initiation factor 5A (eIF5A) to assist METTL3 localizing on its mRNA for m6A modification, then promoting METTL3 expression. Structure-based design, synthesis, and activity screening yielded the hit compound GL-1 as a DHPS inhibitor. Notably, GL-1 directly inhibits DHPS binding to eIF5A, whereas GC-7 cannot. Based on the clarification of the mode of action of GL-1 on DHPS, it is found that GL-1 can promote the accumulation of intracellular Cu2+ to induce apoptosis, and antibody microarray analysis shows that GL-1 inhibits the expression of several cytokines. GL-1 shows promising antitumor activity with good bioavailability in a xenograft tumor model. These findings clarify the molecular mechanisms by which DHPS regulates melanoma proliferation and demonstrate the potential of GL-1 for clinical melanoma therapy.

12.
ACS Appl Mater Interfaces ; 15(40): 47754-47763, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37769117

RESUMO

Solar water splitting from a p-n-conjugated photoelectrochemical (PEC) system is a promising way to produce hydrogen sustainably. At present, finding a compatible p-type photocathode material for the p-n system remains a great challenge in consideration of the photocurrent and stability. This paper highlighted a promising candidate, Rh/BaTiO3, by switching BaTiO3 from an n-type photoanode to a p-type photocathode upon Rh doping. The dopant activated visible light absorption up to 550 nm and an onset potential as high as 1.0 V (vs RHE). Using surface photovoltage spectroscopy as a powerful characterization tool, the n- to p-type transition of the semiconductor was studied and explained microscopically by which we quantitatively isolated the cathodic contribution caused by the Rh dopant. Unbiased overall solar water splitting was accomplished by serially connecting the Pt/Rh/BaTiO3 photocathode to a CoOx/Mo/BiVO4 photoanode, which produced a solar to hydrogen conversion efficiency of 0.1% and an excellent stability over 100 h of operation at ambient pressure. This work revealed the key role that the Rh dopant played in the n- to p-type adjustment of titanate semiconductors and demonstrated its great potential for application in PEC water splitting.

13.
ACS Nano ; 17(4): 3984-3995, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36786231

RESUMO

In theory, electrocatalysts in their metallic forms should be the most stable chemical state under cathodic potentials. It is known that the highly dispersed nanoparticle (NP) types of electrocatalysts often possess higher activity than their bulk counterparts. However, facilely and controllably fabricating well-dispersed nonprecious metal NPs with superior electrocatalytic activity, selectivity, and durability is highly challenging. Here, we report a facile reductive pyrolysis approach to controllably synthesize NiCo alloy NPs confined on the tip of N-doped carbon nanotubes (N-CNTs) from a bimetal-MOF precursor. The electrocatalytic performance of the resultant NiCo@N-CNTs are evaluated by a wide spectrum of nitroarene reductive coupling reactions to produce azoxy-benzenes, a class of precious chemicals for textile, food, cosmetic, and pharmaceutical industries. The superior electrocatalytic stability, full conversion of nitroarenes, >99% selectivities, and >97% faradic efficiencies toward the targeted azoxy-benzene products are readily attainable by NiCo@N-CNTs, attributable to the alloying-induced synergetic effect. The presence of a CNT confinement effect in NiCo@N-CNTs induces high stability. This added to the metallic states of NiCo empowers NiCo@N-CNTs with excellent electrochemical stability under reductive reaction conditions. In an effort to enhance the energy utilization efficiency, we construct a NiCo@N-CNTs||Ni(OH)2/NF two-electrode electrolyzer to simultaneously reduce nitrobenzene at the cathode and 5-hydroxymethylfurfural with >99% yields for both azoxy-benzene and 2,5-furandicarboxylic acid.

14.
Front Neurol ; 14: 1125488, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937528

RESUMO

Background: Dizziness in children, which could not be diagnosed at an early stage in the past, is becoming increasingly clear to a large extent. However, the recognition of the diagnosis and management remains discrepant and controversial due to their complicated and varied etiology. Central and peripheral vestibular disorders, psychogenic and systemic diseases, and genetic pathogeny constitute childhood etiological entities. Further understanding of the etiology and the prevalence of vertigo disorders is of crucial importance and benefit in the diagnosis and management of pediatric patients. Methods: This systematic review and meta-analysis were conducted by systematically searching Embase, PubMed, the Cochrane Library, CNIK, the Chinese Wan-Fang database, CBM, the Chinese VIP database, and the Web of Science for literature on childhood vertigo disorders published up to May 2022. The literature was evaluated under strict screening and diagnostic criteria. Their quality was assessed using the Agency for Healthcare and Research Quality (AHRQ) standards. The test for homogeneity was conducted to determine the fixed effects model or random-effect model employed. Results: Twenty-three retrospective cross-sectional studies involving 7,647 children with vertigo disorders were finally included, with an AHRQ score >4 (high or moderate quality). Our results demonstrated that peripheral vertigo (52.20%, 95% CI: 42.9-61.4%) was more common in children than central vertigo (28.7%, 95% CI: 20.8-37.4%), psychogenic vertigo (7.0%, 95% CI: 4.8-10.0%), and other systemic vertigo (4.7%, 95% CI: 2.6-8.2%). The five most common etiological diagnoses associated with peripheral vertigo included benign paroxysmal vertigo of childhood (BPVC) (19.50%, 95% CI: 13.5-28.3%), sinusitis-related diseases (10.7%, 95% CI: -11.2-32.6%), vestibular or semicircular canal dysfunction (9.20%, 95% CI: 5.7-15.0%), benign paroxysmal positional vertigo (BPPV)(7.20%, 95% CI: 3.9-11.5%), and orthostatic dysregulation (6.8%, 95% CI: 3.4-13.0%). Vestibular migraine (20.3%, 95% CI: 15.4-25.2%) was the most seen etiological diagnosis associated with central vertigo in children. In addition, we found the sex-based difference influenced the outcome of psychogenic vertigo and vestibular migraine, while there was no significant difference in other categories of the etiology. For the management of vertigo, symptomatical management is the first choice for most types of vertigo disorder in pediatrics. Conclusion: Complex etiology and non-specific clinical manifestations of vertigo in pediatrics are challenging for their diagnoses. Reliable diagnosis and effective management depend on the close cooperation of multiple disciplines, combined with comprehensive consideration of the alternative characteristics of vertigo in children with growth and development.

15.
J Food Sci ; 88(4): 1378-1391, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36789871

RESUMO

The purpose of this study is to compare the physicochemical properties and volatile flavor compounds of rose tea obtained by the methods of normal temperature drying, hot-air drying (HAD), and vacuum freeze-drying (VFD) and to evaluate the quality of rose tea. The physicochemical results showed that the content of ascorbic acid (VC) and the pH value was the highest in rose tea obtained by HAD. The contents of anthocyanin, proanthocyanidins, and total phenols were highest in rose tea obtained by VFD. However, there was no significant difference in total flavonoids between drying methods. The volatile organic compounds (VOCs) in rose tea with different drying methods were analyzed by headspace solid-phase microextraction-gas chromatography-mass spectroscopy (HS-SPME-GC-MS) and HS GC-ion mobility spectroscopy (HS-GC-IMS), and the flavor fingerprint of rose tea was established by principal component analysis (PCA). The concentration of VOCs in rose tea varied greatly with different drying methods. The main flavor compounds of rose tea were alcohols, esters, aldehydes, and terpenoids. HS-GC-IMS was used for the identification of volatile flavor compounds of rose tea, thereby helping to assess the quality of rose tea. In addition, the rose tea samples with different drying methods were well distinguished by PCA. This study deepens the understanding of the physicochemical properties and volatile flavor compounds of rose tea with different drying methods and provides a reference for the identification of rose tea with different drying methods. PRACTICAL APPLICATION: This study deepens the understanding of the physicochemical properties and volatile flavor compounds of rose tea with different drying methods and provides a reference for the identification of rose tea with different drying methods. It also provides an effective theoretical basis for consumers to buy rose tea.


Assuntos
Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Análise por Conglomerados , Álcoois/análise , Compostos Orgânicos Voláteis/análise , Chá
16.
Curr Med Chem ; 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37151058

RESUMO

Gastrointestinal stromal tumour (GIST) is a common gastrointestinal sarcoma located in the stromal cells of the digestive tract, and molecular studies have revealed the pathogenesis of mutations in KIT and PDGFRA genes. Since imatinib opened the era of targeted therapy for GIST, tyrosine kinase inhibitors (TKIs) that can treat GIST have been developed successively. However, the lack of new drugs with satisfactory therapeutic standards has made addressing resistance a significant challenge for TKIs in the face of the resistance to first-line and second-line drugs. Therefore, we need to find as many drugs and new treatments that block mutated genes as possible. METHODS: We conducted a comprehensive collection of literature using databases, integrated and analysed the selected literature based on keywords and the comprehensive nature of the articles, and finally wrote articles based on the content of the studies. RESULTS: In this article, we first briefly explained the relationship between GIST and KIT/ PDGFRα and then introduced the related drug treatment. The research progress of TKIs was analyzed according to the resistance of the drugs. CONCLUSION: This article describes the research progress of some TKIs and provides a brief introduction to the currently approved TKIs and some drugs under investigation that may have better therapeutic effects, hoping to provide clues to the research of new drugs.

17.
Curr Top Med Chem ; 23(12): 1043-1064, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36852801

RESUMO

Pyrazolo[1,5-a]pyrimidines are fused heterocycles that have spawned many biologically active antitumor drugs and are important privileged structures for drug development. Pyrazolo[1,5- a]pyrimidine derivatives have played an important role in the development of antitumor agents due to their structural diversity and good kinase inhibitory activity. In addition to their applications in traditional drug targets such as B-Raf, KDR, Lck, and Src kinase, some small molecule drugs with excellent activity against other kinases (Aurora, Trk, PI3K-γ, FLT-3, C-Met kinases, STING, TRPC) have emerged in recent years. Therefore, based on these antitumor drug targets, small molecule inhibitors containing pyrazolo[1,5-a]pyrimidine scaffold and their structure-activity relationships are summarized and discussed to provide more reference value for the application of this particular structure in antitumor drugs.


Assuntos
Antineoplásicos , Antineoplásicos/farmacologia , Antineoplásicos/química , Relação Estrutura-Atividade , Pirimidinas/farmacologia , Pirimidinas/química , Estrutura Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Ensaios de Seleção de Medicamentos Antitumorais
18.
Front Nutr ; 9: 889407, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923198

RESUMO

Radish (Raphanus sativus L.) is an important Brassicaceous vegetable crop that is cultivated worldwide. The taste of radish can be described as pungent, sweet, and crisp. At present, the metabolic characteristics leading to differences in radish taste remain unclear, due to the lack of large-scale detection and identification of radish metabolites. In this study, UPLC-MS/MS-based targeted metabolome analysis was performed on the taproots of eight radish landraces. We identified a total of 938 metabolites, and each landrace exhibited a specific metabolic profile, making it unique in flavor and quality. Our results show that taste differences among the taproots of different radish landraces can be explained by changes in composition and abundance of glucosinolates, polyphenols, carbohydrates, organic acids, amino acids, vitamins, and lipids. This study reveals the potential metabolic causes of variation in the taste and flavor of radish taproots.

19.
ACS Appl Mater Interfaces ; 14(30): 34656-34664, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35860844

RESUMO

The surface states of a semiconductor photocatalyst are essential for interfacial charge transfer in heterogeneous photocatalytic reactions. Here, we report that the light-driven hydrogen evolution reaction (HER) activity of 0.5 mol % Rh-doped rutile increases by more than 30 times compared with that of rutile when ascorbic acid is used as a sacrificial agent. Intensity-modulated photocurrent spectroscopy and surface photovoltage spectroscopy are employed to reveal the impact of surface states on the photo-oxidation reactions. It is found that the adsorption of ascorbic acid molecules dramatically reduces the activity of rutile due to coverage of the HER-active Ti sites. Nevertheless, for Rh-doped rutile, ascorbic acid neutralizes the Rh(IV) sites that would otherwise cause severe recombination of electron-hole pairs and resurrects its photocatalytic performance. This work demonstrates the key role of interfacial chemistry in photocatalytic reactions and provides a strategy for excavating the potential of various photocatalysts.

20.
Redox Biol ; 57: 102472, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36162258

RESUMO

Age-related hearing loss (ARHL) is the most prevalent sensory disorder in the elderly. Currently, no treatment can effectively prevent or reverse ARHL. Aging auditory organs are often accompanied by exacerbated oxidative stress and metabolic deterioration. Here, we report the effect of deuterated oxygen (D2O), also known as "heavy water", mouse models of ARHL. Supplementing the normal mouse diet with 10% D2O from 4 to 9 weeks of age lowered hearing thresholds at selected frequencies in treated mice compared to untreated control group. Oxidative stress levels were significantly reduced and in the cochlear duct of treated vs. untreated mice. Through metabolic flux analysis, we found that D2O mainly slowed down catabolic reactions, and may delay metabolic deterioration related to aging to a certain extent. Experiments confirmed that the Nrf2/HO-1/glutathione axis was down-regulated in treated mice. Thus, D2O supplementation can hinder ARHL progression in mouse models by slowing the pace of metabolism and reducing endogenous oxidative stress production in the cochlea. These findings open new avenues for protecting the cochlea from oxidative stress and regulating metabolism to prevent ARHL.

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