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Cycling cells replicate their DNA during the S phase through a defined temporal program known as replication timing. Mutation frequencies, epigenetic chromatin states, and transcriptional activities are different for genomic regions that are replicated early and late in the S phase. Here, we found from ChIP-Seq analysis that DNA polymerase (Pol) κ is enriched in early-replicating genomic regions in HEK293T cells. In addition, by feeding cells with N 2-heptynyl-2'-deoxyguanosine followed by click chemistry-based enrichment and high-throughput sequencing, we observed elevated Pol κ activities in genomic regions that are replicated early in the S phase. On the basis of the established functions of Pol κ in accurate and efficient nucleotide insertion opposite endogenously induced N 2-modified dG lesions, our work suggests that active engagement of Pol κ may contribute to diminished mutation rates observed in early-replicating regions of the human genome, including cancer genomes. Together, our work expands the functions of Pol κ and offered a plausible mechanism underlying replication timing-dependent mutation accrual in the human genome.
Assuntos
Replicação do DNA , DNA Polimerase Dirigida por DNA , Fase S , Humanos , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , Células HEK293 , Genoma Humano , Período de Replicação do DNARESUMO
Proanthocyanidins (PAs) are an important group of flavonoids that contribute to astringency, color, and flavor in grapes (Vitis vinifera) and wines. They also play a crucial role in enhancing plant resistance to various stresses. However, the underlying regulatory mechanism governing PAs biosynthesis, particularly in relation to conferring resistance to powdery mildew, has not been extensively explored. This study focused on identifying a key player in PAs biosynthesis, namely the plant U-box (PUB) E3 ubiquitin ligase VvPUB26. We discovered that overexpression of VvPUB26 in grapes leads to a significant increase in PAs content, whereas interfering with VvPUB26 has the opposite effect. Additionally, our findings demonstrated that overexpression of VvPUB26 in transgenic grapevines enhances defense against powdery mildew while interfering with VvPUB26 results in increased susceptibility to the pathogen. Interestingly, we observed that VvPUB26 interacts with the WRKY transcription factor VvWRKY24, thereby facilitating ubiquitination and degradation processes. Through RNA-Seq analysis, we found that VvWRKY24 primarily participates in secondary metabolites biosynthesis, metabolic pathways, and plant-pathogen interaction. Notably, VvWRKY24 directly interacts with the promoters of dihydroflavonol-4-reductase (DFR) and leucoanthocyanidin reductase (LAR) to inhibit PAs biosynthesis. Meanwhile, VvWRKY24 also influences the expression of MYB transcription factor genes related to PAs synthesis. In conclusion, our results unveil a regulatory module involving VvPUB26-VvWRKY24-VvDFR/VvLAR that plays a fundamental role in governing PAs biosynthesis in grapevines. These findings enhance our understanding of the relationship between PAs biosynthesis and defense mechanisms against powdery mildew.
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Ascomicetos , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Doenças das Plantas , Proteínas de Plantas , Proantocianidinas , Vitis , Vitis/genética , Vitis/microbiologia , Vitis/enzimologia , Proantocianidinas/biossíntese , Proantocianidinas/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Resistência à Doença/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ascomicetos/fisiologia , Ascomicetos/patogenicidade , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Plantas Geneticamente ModificadasRESUMO
Neurotropic viral infections pose a significant challenge due to their ability to target the central nervous system and cause severe neurological complications. Traditional antiviral therapies face limitations in effectively treating these infections, primarily due to the blood-brain barrier, which restricts the delivery of therapeutic agents to the central nervous system. Nanoparticle-based therapies have emerged as a promising approach to overcome these challenges. Nanoparticles offer unique properties that facilitate drug delivery across biological barriers, such as the blood-brain barrier, and can be engineered to possess antiviral activities.
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Antivirais , Barreira Hematoencefálica , Viroses do Sistema Nervoso Central , Nanopartículas , Humanos , Nanopartículas/química , Antivirais/uso terapêutico , Antivirais/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Viroses do Sistema Nervoso Central/tratamento farmacológico , Viroses do Sistema Nervoso Central/virologia , Sistemas de Liberação de Medicamentos , Viroses/tratamento farmacológico , Viroses/virologiaRESUMO
In females, the pathophysiological mechanism of poor ovarian response (POR) is not fully understood. Considering the expression level of p62 was significantly reduced in the granulosa cells (GCs) of POR patients, this study focused on identifying the role of the selective autophagy receptor p62 in conducting the effect of follicle-stimulating hormone (FSH) on antral follicles (AFs) formation in female mice. The results showed that p62 in GCs was FSH responsive and that its level increased to a peak and then decreased time-dependently either in ovaries or in GCs after gonadotropin induction in vivo. GC-specific deletion of p62 resulted in subfertility, a significantly reduced number of AFs and irregular estrous cycles, which were same as pathophysiological symptom of POR. By conducting mass spectrum analysis, we found the ubiquitination of proteins was decreased, and autophagic flux was blocked in GCs. Specifically, the level of nonubiquitinated Wilms tumor 1 homolog (WT1), a transcription factor and negative controller of GC differentiation, increased steadily. Co-IP results showed that p62 deletion increased the level of ubiquitin-specific peptidase 5 (USP5), which blocked the ubiquitination of WT1. Furthermore, a joint analysis of RNA-seq and the spatial transcriptome sequencing data showed the expression of steroid metabolic genes and FSH receptors pivotal for GCs differentiation decreased unanimously. Accordingly, the accumulation of WT1 in GCs deficient of p62 decreased steroid hormone levels and reduced FSH responsiveness, while the availability of p62 in GCs simultaneously ensured the degradation of WT1 through the ubiquitinâproteasome system and autophagolysosomal system. Therefore, p62 in GCs participates in GC differentiation and AF formation in FSH induction by dynamically controlling the degradation of WT1. The findings of the study contributes to further study the pathology of POR.
Assuntos
Hormônio Foliculoestimulante , Células da Granulosa , Folículo Ovariano , Proteína Sequestossoma-1 , Ubiquitinação , Proteínas WT1 , Animais , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , Feminino , Proteínas WT1/metabolismo , Proteínas WT1/genética , Camundongos , Folículo Ovariano/metabolismo , Folículo Ovariano/efeitos dos fármacos , Células da Granulosa/metabolismo , Células da Granulosa/efeitos dos fármacos , Proteína Sequestossoma-1/metabolismo , Proteína Sequestossoma-1/genética , Camundongos Endogâmicos C57BL , Autofagia/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Humanos , Camundongos KnockoutRESUMO
BACKGROUND: Plants differ more than threefold in seed oil contents (SOCs). Soybean (Glycine max), cotton (Gossypium hirsutum), rapeseed (Brassica napus), and sesame (Sesamum indicum) are four important oil crops with markedly different SOCs and fatty acid compositions. RESULTS: Compared to grain crops like maize and rice, expanded acyl-lipid metabolism genes and relatively higher expression levels of genes involved in seed oil synthesis (SOS) in the oil crops contributed to the oil accumulation in seeds. Here, we conducted comparative transcriptomics on oil crops with two different SOC materials. In common, DIHYDROLIPOAMIDE DEHYDROGENASE, STEAROYL-ACYL CARRIER PROTEIN DESATURASE, PHOSPHOLIPID:DIACYLGLYCEROL ACYLTRANSFERASE, and oil-body protein genes were both differentially expressed between the high- and low-oil materials of each crop. By comparing functional components of SOS networks, we found that the strong correlations between genes in "glycolysis/gluconeogenesis" and "fatty acid synthesis" were conserved in both grain and oil crops, with PYRUVATE KINASE being the common factor affecting starch and lipid accumulation. Network alignment also found a conserved clique among oil crops affecting seed oil accumulation, which has been validated in Arabidopsis. Differently, secondary and protein metabolism affected oil synthesis to different degrees in different crops, and high SOC was due to less competition of the same precursors. The comparison of Arabidopsis mutants and wild type showed that CINNAMYL ALCOHOL DEHYDROGENASE 9, the conserved regulator we identified, was a factor resulting in different relative contents of lignins to oil in seeds. The interconnection of lipids and proteins was common but in different ways among crops, which partly led to differential oil production. CONCLUSIONS: This study goes beyond the observations made in studies of individual species to provide new insights into which genes and networks may be fundamental to seed oil accumulation from a multispecies perspective.
Assuntos
Produtos Agrícolas , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Óleos de Plantas , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Óleos de Plantas/metabolismo , Perfilação da Expressão Gênica/métodos , Transcriptoma , Sementes/genética , Sementes/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
N2-Alkyl-2'-deoxyguanosine (N2-alkyl-dG) is a major type of minor-groove DNA lesions arising from endogenous metabolic processes and exogenous exposure to environmental contaminants. The N2-alkyl-dG lesions, if left unrepaired, can block DNA replication and transcription and induce mutations in these processes. Nevertheless, the repair pathways for N2-alkyl-dG lesions remain incompletely elucidated. By utilizing a photo-cross-linking coupled with mass spectrometry-based quantitative proteomic analysis, we identified a series of candidate N2-alkyl-dG-binding proteins. We found that two of these proteins, i.e., high-mobility group protein B3 (HMGB3) and SUB1, could bind directly to N2-nBu-dG-containing duplex DNA in vitro and promote the repair of this lesion in cultured human cells. In addition, HMGB3 and SUB1 protected cells against benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE). SUB1 exhibits preferential binding to both the cis and trans diastereomers of N2-BPDE-dG over unmodified dG. On the other hand, HMGB3 binds favorably to trans-N2-BPDE-dG; the protein, however, does not distinguish cis-N2-BPDE-dG from unmodified dG. Consistently, genetic ablation of HMGB3 conferred diminished repair of trans-N2-BPDE-dG, but not its cis counterpart, whereas loss of SUB1 conferred attenuated repair of both diastereomers. Together, we identified proteins involved in the cellular sensing and repair of minor-groove N2-alkyl-dG lesions and documented a unique role of HMGB3 in the stereospecific recognition and repair of N2-BPDE-dG.
Assuntos
Reparo do DNA , DNA , Proteína HMGB3 , Humanos , DNA/química , DNA/metabolismo , Dano ao DNA , Enzimas Reparadoras do DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/química , Guanina/química , Guanina/metabolismo , Proteína HMGB3/metabolismo , Proteína HMGB3/química , Ligação ProteicaRESUMO
PURPOSE: This study was the first to evaluate the effect of CYP3A5*3 gene polymorphisms on plasma concentration of perampanel (PER) in Chinese pediatric patients with epilepsy. METHODS: We enrolled 98 patients for this investigation. Plasma PER concentrations were measured using liquid chromatography-tandem mass spectrometry. Leftover samples from standard therapeutic drug monitoring were allocated for genotyping analysis. The primary measure of efficacy was the rate of seizure reduction with PER treatment at the final checkup. RESULTS: The plasma concentration showed a linear correlation with the daily dose taken ( r â =â 0.17; P â <â 0.05). The ineffective group showed a significantly lower plasma concentration of PER (490.5â ±â 297.1 vs. 633.8â ±â 305.5â µg/ml; P â =â 0.019). For the mean concentration-to-dose (C/D) ratio, the ineffective group showed a significantly lower C/D ratio of PER (3.2â ±â 1.7 vs. 3.8â ±â 2.0; P â =â 0.040). The CYP3A5*3 CC genotype exhibited the highest average plasma concentration of PER at 562.8â ±â 293.9 ng/ml, in contrast to the CT and TT genotypes at 421.1â ±â 165.6 ng/ml and 260.0â ±â 36.1 ng/ml. The mean plasma PER concentration was significantly higher in the adverse events group (540.8â ±â 285.6 vs. 433.0â ±â 227.2 ng/ml; P â =â 0.042). CONCLUSION: The CYP3A5*3 gene's genetic polymorphisms influence plasma concentrations of PER in Chinese pediatric patients with epilepsy. Given that both efficacy and potential toxicity are closely tied to plasma PER levels, the CYP3A5*3 genetic genotype should be factored in when prescribing PER to patients with epilepsy.
Assuntos
Anticonvulsivantes , Citocromo P-450 CYP3A , Epilepsia , Nitrilas , Piridonas , Humanos , Citocromo P-450 CYP3A/genética , Criança , Feminino , Masculino , Epilepsia/tratamento farmacológico , Epilepsia/genética , Nitrilas/farmacocinética , Piridonas/farmacocinética , Piridonas/administração & dosagem , Piridonas/efeitos adversos , Pré-Escolar , Anticonvulsivantes/farmacocinética , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/efeitos adversos , Polimorfismo de Nucleotídeo Único/genética , Genótipo , Adolescente , Povo Asiático/genética , População do Leste AsiáticoRESUMO
There is an urgent need for an oral, efficient and safe regimen for high-risk APL under the pandemic of COVID-19. We retrospectively analysed 60 high-risk APL patients. For induction therapy (IT), in addition to all-trans retinoic acid (ATRA) and oral arsenic (RIF), 22 patients received oral etoposide (VP16) as cytotoxic chemotherapy (CC), and 38 patients received intravenous CC as historical control group. The median dose of oral VP16 was 1000 mg [interquartile rage (IQR), 650-1250]. One patient died during IT in the control group, 59 evaluable patients (100%) achieved complete haematological remission (CHR) after IT and complete molecular remission (CMR) after consolidation therapy. The median time to CHR and CMR was 36 days (33.8-44) versus 35 days (32-42; p = 0.75) and 3 months (0.8-3.5) versus 3.3 months (2.4-3.7; p = 0.58) in the oral VP16 group and in the control group. Two (9.1%) and 3 (7.9%) patients experienced molecular relapse in different group respectively. The 2-year estimated overall survival and event-free survival were 100% versus 94.7% (p = 0.37) and 90.9% versus 89.5% (p = 0.97) respectively. A completely oral, efficient and safe induction regimen including oral VP16 as cytoreductive chemotherapy combined with ATRA and RIF is more convenient to administer for patients with high-risk APL.
Assuntos
Etoposídeo , Quimioterapia de Indução , Leucemia Promielocítica Aguda , Humanos , Etoposídeo/administração & dosagem , Etoposídeo/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Administração Oral , Estudos Retrospectivos , Quimioterapia de Indução/métodos , Infusões Intravenosas , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , COVID-19 , Tretinoína/administração & dosagem , Tretinoína/uso terapêutico , SARS-CoV-2 , Indução de Remissão , Arsênio/administração & dosagem , IdosoRESUMO
Intermolecular interactions are critical to the crystallization of biomolecules, yet the precise control of biomolecular crystal growth based on these interactions remains elusive. To understand the connections between the crystallization kinetics and the strength of intermolecular interactions, herein we have employed DNA triangular crystals and modified ones as a versatile tool to investigate how the strength of intermolecular interaction affects crystal growth. Interestingly, we have found that the 2'-O-methylation at sticky ends of the DNA triangle could strengthen its intermolecular interaction, resulting in the accelerated formation of smaller crystals. Conversely, phosphorothioate modification could weaken the sticky-end cohesion and delay the nucleation, resulting in formation of fewer but larger crystals. In addition, these modification effects were consistently observed in the crystallization of a DNA decamer. In one word, our experimental results demonstrate that the strength of intermolecular interaction directly impacts crystal growth. It suggests that 2'-O-methylation and phosphorothioate modification represents a rational strategy for controlling DNA molecules grow into desired crystals and it also facilitates structural determination.
Assuntos
Cristalização , DNA , DNA/química , Cinética , Metilação , Conformação de Ácido NucleicoRESUMO
Acrylamide (ACR) is a common industrial contaminant with endocrine-disrupting toxicity. Numerous studies have indicated that females and diabetics are more sensitive to environmental contaminants. However, it remains unknown whether female diabetics are susceptible to ACR-induced toxicity and its potential mechanisms. Thus, the female ACR-exposure diabetic Balb/c mice model was established to address these issues. Results showed that ACR could induce liver injury in normal mice and cause more serious inflammatory cell infiltration, hepatocyte volume increase, and fusion in diabetic mice liver. Meanwhile, ACR could lead to exacerbation of diabetic symptoms in diabetic mice by disturbing the glucose and lipid metabolism in the liver, which mainly manifests as the accumulation of liver glycogen and liver lipids, the reduction of the activity/content of glycolytic and metabolizing enzyme as well as pentose phosphatase, upregulation of the gene expression in fatty acid transporter and gluconeogenesis, and downregulation of the gene expression in fatty acid synthesis and metabolism. Moreover, ACR exposure could induce oxidative stress, inflammation, and endoplasmic reticulum stress in the liver by a decrease in hepatic antioxidant enzyme activity and antioxidant content, an increase in inflammatory factor levels, and a change in the related protein expression of endoplasmic reticulum stress (ERS) and apoptosis-related pathways in diabetic mice. Statistical analysis results revealed that ACR-induced liver injury was highly correlated with inflammation and oxidative stress, and ERS and diabetic mice had a higher risk of liver injury than normal mice. Overall results suggested that female diabetic mice easily suffer from ACR-induced toxicity, and the reason was that ACR could induce further damage to the liver by worsening the condition of inflammation, oxidative stress, and ERS in the liver.
Assuntos
Acrilamida , Diabetes Mellitus Experimental , Estresse do Retículo Endoplasmático , Camundongos Endogâmicos BALB C , Animais , Feminino , Acrilamida/toxicidade , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Camundongos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Estresse Oxidativo/efeitos dos fármacosRESUMO
BACKGROUND: The MS disease-modifying therapies (DMTs) prescribing landscape in Australia have changed over time. OBJECTIVES: This study evaluated the utilisation and cost trends of MS-related DMTs in Australia over 10 years and investigated differences between States/Territories. METHODS: The prescription and costs of 16 DMTs were extracted from the Pharmaceutical Benefits Scheme for 2013-2022. Descriptive approaches analysed the total number of people prescribed DMTs and total DMT costs per 10,000 population, proportions of prescriptions/costs by DMT groups and the number of people prescribed each individual DMT and costs of each DMT over the 10-year period. All estimates were for Australia and each State/Territory individually. RESULTS: The number of people prescribed DMT and costs per 10,000 population had substantial growth between 2013 and 2022: 125%/164% for Australia, and 94%-251%/129%-373% for individual States/Territories. Higher efficacy group accounted for 54% of total people prescribed DMTs in 2013 and 75% in 2022. Fingolimod was the most popular DMT until 2020, then was dominated by ocrelizumab. The trends of individual DMT prescriptions and costs differed between states particularly in Western Australia (WA), Tasmania and Northern Territory (NT). CONCLUSION: DMT prescriptions and costs continuously increased over the last decade, particularly for higher efficacy DMTs, and their trends differed between States/Territories.
Assuntos
Esclerose Múltipla , Humanos , Esclerose Múltipla/epidemiologia , Cloridrato de Fingolimode , AustráliaRESUMO
BACKGROUND: Multiple sclerosis (MS) prevalence is increasing globally. OBJECTIVES: To determine whether increased prevalence is continuing within Australia using our validated prescription-based ascertainment method. METHODS: We used methods employed in our 2010 and 2017 prevalence estimates. Disease-modifying therapy (DMT) prescriptions were extracted from Australia's Pharmaceutical Benefits Scheme data for January-December 2021. DMT penetrance was calculated using data from the Australian MS Longitudinal Study. We divided the total number of monthly prescriptions by 12 or 2 (except alemtuzumab), adjusted for DMT penetrance and Australian population estimates. Prevalences in Australian states/territories were age-standardised. 2021 prevalence estimates were compared with 2010 and 2017 prevalence estimates using Poisson regression. RESULTS: Number of people with MS in Australia in 2021 was 33,335; an increase of 7728 from 2017 (30.2%) and 12,092 from 2010 (56.6%) and increasing at a faster rate than population change (+10.1%, +14.1%). Age-standardised prevalence was 136.1/100,000 (increased from 103.7/100,000 in 2017). The previously demonstrated positive latitudinal gradient in 2010 and 2017 persisted in 2021, with Tasmania (southernmost state) having the highest prevalence (age-standardised: 203.5/100,000) while northernmost states had the lowest. CONCLUSIONS: In line with global trends, MS prevalence is escalating in Australia, particularly in higher-latitude states. MS prevention is crucial to halt this disturbing trend.
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The application of tyrosine kinase inhibitors (TKIs) and novel immunotherapies has improved outcomes in patients with Ph + acute lymphoblastic leukaemia (ALL), and the issue of whether there is still a need for stem cell transplantation has become controversial. We performed a retrospective study to explore whether stem cell transplantation still held a place in patients with Ph + ALL if only imatinib and 2nd generation TKIs are available and affordable. A total of 292 patients were included. The median age was 38 years [range 14-64, IQR 28-48]. Patients receiving transplants (n = 216) had better rates of 4-year disease-free survival (DFS, 68% vs. 24%, P < .0001) and overall survival (OS, 72% vs. 47%, P < .0001) than those receiving continuous TKIs plus chemotherapy (TKI-chemo) (n = 76). In the multivariate analysis, male sex, WBC count ≥ 95 × 109/L and PLT count ≤ 154 × 109/L at diagnosis were significantly associated with poorer outcomes, and transplantation was significantly associated with favourable DFS and OS. In addition, the transplant outcomes were superior in any subgroup according to the number of risk variables. Furthermore, propensity score matching (PSM) analyses showed similar findings in the whole cohort and in age- and BCR-ABL1 level-based subgroups after the first or second consolidation. In conclusion, transplantation as a one-time procedure for adults with Ph + ALL patients remains important in countries lacking accessibility to third-generation TKIs or immunotherapies, regardless of the depth of the molecular response.
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Dihydroorotate dehydrogenase (DHODH)-mediated ferroptosis defense is a targetable vulnerability in cancer. Currently, only a few DHODH inhibitors have been utilized in clinical practice. To further enhance DHODH targeting, we introduced the mitochondrial targeting group triphenylphosphine (TPP) to brequinar (BRQ), a robust DHODH inhibitor, resulting in the creation of active molecule B2. This compound exhibits heightened anticancer activity, effectively inhibiting proliferation in various cancer cells, and restraining tumor growth in melanoma xenografts in mice. B2 achieves these effects by targeting DHODH, triggering the formation of reactive oxygen species (ROS), promoting mitochondrial lipid peroxidation, and inducing ferroptosis in B16F10 and A375 cells. Surprisingly, B2 significantly downregulates PD-L1 and alleviates immune suppression. Importantly, B2 exhibits no apparent adverse effects in mice. Collectively, these findings highlight that enhancing the mitochondrial targeting capability of the DHODH inhibitor is a promising therapeutic approach for melanoma treatment.
Assuntos
Ferroptose , Melanoma , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Humanos , Animais , Camundongos , Di-Hidro-Orotato Desidrogenase , Melanoma/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , MitocôndriasRESUMO
Creating affordable electrocatalysts and understanding the real-time catalytic process of the urea oxidation reaction (UOR) are crucial for advancing urea-based technologies. Herein, a Cu-Ni based selenide electrocatalyst (CuSey/NiSex/NF) was created using a hydrothermal technique and selenization treatment, featuring a heterogeneous interface rich in Cu2-xSe, Cu3Se2, Ni3Se4, and NiSe2. This catalyst demonstrated outstanding urea electrooxidation performance, achieving 10 mA cm-2 with just 1.31 V and sustaining stability for 96 h. Through in-situ Raman spectroscopy and ex-situ characterizations, it is discovered that NiOOH is formed through surface reconstruction in the UOR process, with high-valence Ni serving as the key site for effective urea oxidation. Moreover, the electrochemical analysis revealed that CuSey had dual effects. An analysis of XPS and electrochemical tests revealed that electron transfer from CuSey to NiSex within the CuSey/NiSex/NF heterostructure enhanced the UOR kinetics of the catalyst. Additionally, according to the in-situ Raman spectroscopy findings, the existence of CuSey facilitates a easier and faster surface reconstruction of NiSex, leading to the creation of additional active sites for urea oxidation. More significantly, this work provides an excellent "precatalyst" for highly efficient UOR, along with an in-depth understanding of the mechanism behind the structural changes in electrocatalysts and the discovery of their true active sites.
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A water mediated three-component reaction of isatin, 4-aminocoumarin, and 1,3-cyclodicarbonyl compounds is reported for the synthesis of spiro[chromeno[4,3-b]cyclopenta[e]pyridine-7,3'-indoline]trione and the spiro[chromeno[4,3-b]quinoline 7,3'-indoline]trione. Up to 27 different spirooxindole derivatives were synthesized by this method. The bioactivity of these spirooxindole derivatives was evaluated and they were found to show antifungal activity against Cercospora arachidicola, Physalospora piricola, Rhizoctonia cerealis, and Fusarium moniliforme.
Assuntos
Antifúngicos , Benzopiranos , Indóis , Nitrilas , Compostos de Espiro , Água , Antifúngicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Compostos de Espiro/farmacologia , Compostos de Espiro/química , Compostos de Espiro/síntese química , Água/química , Indóis/química , Indóis/farmacologia , Indóis/síntese química , Testes de Sensibilidade Microbiana , Oxindóis/farmacologia , Oxindóis/síntese química , Oxindóis/química , Estrutura Molecular , Relação Estrutura-Atividade , Fusarium/efeitos dos fármacosRESUMO
The adsorption and activation of pollutant molecules and oxygen play a critical role in the oxidation reaction of volatile organic compounds (VOCs). In this study, superior adsorption and activation ability was achieved by modulating the interaction between Pt nanoparticles (NPs) and UiO-66 (U6) through the spatial position effect. Pt@U6 exhibits excellent activity in toluene, acetone, propane, and aldehyde oxidation reactions. Spectroscopic studies, 16O2/18O2 kinetic isotopic experiments, and density functional theory (DFT) results jointly reveal that the encapsulated Pt NPs of Pt@U6 possess higher electron density and d-band center, which is conducive for the adsorption and dissociation of oxygen. The toluene oxidation reaction and DFT results indicate that Pt@U6 is more favorable to activate the C-H of toluene and the CâC of maleic anhydride, while Pt/U6 with lower electron density and d-band center exhibits a higher oxygen dissociation temperature and higher reactant activation energy barriers. This study provides a deep insight into the architecture-performance relation of Pt-based catalysts for the catalytic oxidation of VOCs.
Assuntos
Estruturas Metalorgânicas , Nanopartículas , Ácidos Ftálicos , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/química , Tolueno/química , OxigênioRESUMO
Nitrous oxide (N2O) has a detrimental impact on the greenhouse effect, and its efficient catalytic decomposition at low temperatures remains challenging. Herein, the cobalt-based high-entropy oxide with a spinel-type structure (Co-HEO) is successfully fabricated via a facile coprecipitation method for N2O catalytic decomposition. The obtained Co-HEO catalyst displays more remarkable catalytic performance and higher thermal stability compared with single and binary Co-based oxides, as the temperature of 90% N2O decomposition (T90) is 356 °C. A series of characterization results reveal that the synergistic effect of multiple elements enhances the reducibility and augments oxygen vacancy in the high-entropy system, thus boosting the activity of the Co-HEO catalyst. Moreover, density functional theory (DFT) calculations and the temperature-programmed surface reaction (TPSR) with isotope labeling demonstrate that N2O decomposition on the Co-HEO catalyst follows the Langmuir-Hinshelwood (L-H) mechanism with the promotion of abundant oxygen vacancies. This work provides a fundamental understanding of the synergistic catalytic effect in N2O decomposition and paves the way for the novel environmental catalytic applications of HEO.
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Cobalto , Óxidos , Entropia , Óxidos/química , Cobalto/química , OxigênioRESUMO
Environmental endocrine disrupting chemicals (EDCs), are a type of exogenous organic pollutants, are ubiquitous in natural aquatic environments. Currently, in addition to neurological, endocrine, developmental and reproductive toxicity, ecotoxicology studies on immunotoxicity are receiving increasing attention. In this review, the composition of immune system of zebrafish, the common indicators of immunotoxicity, the immunotoxicity of EDCs and their molecular mechanism were summarized. We reviewed the immunotoxicity of EDCs on zebrafish mainly in terms of immune organs, immunocytes, immune molecules and immune functions, meanwhile, the possible molecular mechanisms driving these effects were elucidated in terms of endocrine disruption, dysregulation of signaling pathways, and oxidative damage. Hopefully, this review will provide a reference for further investigation of the immunotoxicity of EDCs.
Assuntos
Disruptores Endócrinos , Animais , Disruptores Endócrinos/toxicidade , Peixe-Zebra , Sistema Imunitário , Reprodução , EcotoxicologiaRESUMO
Irisin is considered to be a promising therapeutic approach for cardiac depression and inflammatory disorders. The short half-life of irisin impeded its use and drug efficacy in the treatment. This study aimed to examine if pegylated gold nanoparticles-conjugated to irisin would improve therapeutic effects in cecal ligation and puncture (CLP)-induced sepsis in mice. Recombinant irisin were conjugated to a pegylated gold nanoparticle, which was given to mice exposed to CLP. The cecal ligation procedure and sham on mice were operated and assigned to one of following five groups: (I) CLP group: The mouse models underwent the CLP surgical procedure and received only vehicle saline treatment (n = 5); (II) CLP + soluble Irisin: The mouse underwent the CLP and received an intramuscular injection (i.m) (TA) injection of 1 ug of soluble irisin into each tibialis anterior (TA) leg (n = 5); (III) CLP + Gold nanoparticle-conjugated to Irisin: The mouse models underwent the CLP and received an i.m (TA) injection of 1 µg of Gold nanoparticle-irisin via intramuscular injection (TA) into each leg (n = 5); (IV) CLP + Gold nanoparticles- conjugated to IgG: The mouse underwent the CLP and received an i.m (TA) injection of gold nanoparticles conjugated to IgG (n = 5). (V) Sham: The mouse underwent the surgical operation without conducting the CLP (n = 10). The post-operated animals were observed for one week, and survival rates were estimated. Echocardiography was performed to measure cardiac function at 12 h following CLP. TUNEL was employed to detect apoptosis in both cardiac and skeletal muscles; histology was conducted to assess tissue injury in muscles. Enzyme linked immunosorbent assay (ELISA) was conducted to examine release of interleukin 6 (IL6) and the tumor necrosis factor (TNF) alpha. Compared to the CLP control, soluble irisin treatment improved cardiac function recovery, as indicated by the fractional shortening (FS) and ejection fraction (EF). Irisin treatment exhibited reduced IL6 and TNF-alpha release in association with less apoptosis, lower muscle injury index and improved survival post-CLP. However, compared to soluble irisin treatment, gold nanoparticles-conjugated to irisin showed a significant improvement in cardiac function, suppression of apoptosis, reduced IL6 and TNF-alpha releases, decreased muscle injury and an improved survival rate of post-CLP. This study reveals that gold nanoparticles-conjugated irisin can serve to improve irisin's therapeutic effects over a longer course of treatment.