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1.
Nucleic Acids Res ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39265120

RESUMEN

Perturb-Seq combines CRISPR (clustered regularly interspaced short palindromic repeats)-based genetic screens with single-cell RNA sequencing readouts for high-content phenotypic screens. Despite the rapid accumulation of Perturb-Seq datasets, there remains a lack of a user-friendly platform for their efficient reuse. Here, we developed PerturbDB (http://research.gzsys.org.cn/perturbdb), a platform to help users unveil gene functions using Perturb-Seq datasets. PerturbDB hosts 66 Perturb-Seq datasets, which encompass 4 518 521 single-cell transcriptomes derived from the knockdown of 10 194 genes across 19 different cell lines. All datasets were uniformly processed using the Mixscape algorithm. Genes were clustered by their perturbed transcriptomic phenotypes derived from Perturb-Seq data, resulting in 421 gene clusters, 157 of which were stable across different cellular contexts. Through integrating chemically perturbed transcriptomes with Perturb-Seq data, we identified 552 potential inhibitors targeting 1409 genes, including an mammalian target of rapamycin (mTOR) signaling inhibitor, retinol, which was experimentally verified. Moreover, we developed a 'Cancer' module to facilitate the understanding of the regulatory role of genes in cancer using Perturb-Seq data. An interactive web interface has also been developed, enabling users to visualize, analyze and download all the comprehensive datasets available in PerturbDB. PerturbDB will greatly drive gene functional studies and enhance our understanding of the regulatory roles of genes in diseases such as cancer.

2.
Proc Natl Acad Sci U S A ; 119(13): e2025606119, 2022 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-35312361

RESUMEN

SignificanceThe permanent disappearance of mass-independent sulfur isotope fractionation (S-MIF) from the sedimentary record has become a widely accepted proxy for atmospheric oxygenation. This framework, however, neglects inheritance from oxidative weathering of pre-existing S-MIF-bearing sedimentary sulfide minerals (i.e., crustal memory), which has recently been invoked to explain apparent discrepancies within the sulfur isotope record. Herein, we demonstrate that such a crustal memory effect does not confound the Carletonville S-isotope record; rather, the pronounced Δ33S values identified within the Rooihoogte Formation represent the youngest known unequivocal oxygen-free photochemical products. Previously observed 33S-enrichments within the succeeding Timeball Hill Formation, however, contrasts with our record, revealing kilometer-scale heterogeneities that highlight significant uncertainties in our understanding of the dynamics of Earth's oxygenation.

3.
J Mol Cell Cardiol ; 191: 76-87, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38718920

RESUMEN

The reactivated adult epicardium produces epicardium-derived cells (EPDCs) via epithelial-mesenchymal transition (EMT) to benefit the recovery of the heart after myocardial infarction (MI). SMARCA4 is the core catalytic subunit of the chromatin re-modeling complex, which has the potential to target some reactivated epicardial genes in MI. However, the effects of epicardial SMARCA4 on MI remain uncertain. This study found that SMARCA4 was activated over time in epicardial cells following MI, and some of activated cells belonged to downstream differentiation types of EPDCs. This study used tamoxifen to induce lineage tracing and SMARCA4 deletion from epicardial cells in Wt1-CreER;Smarca4fl/fl;Rosa26-RFP adult mice. Epicardial SMARCA4 deletion reduces the number of epicardial cells in adult mice, which was related to changes in the activation, proliferation, and apoptosis of epicardial cells. Epicardial SMARCA4 deletion reduced collagen deposition and angiogenesis in the infarcted area, exacerbated cardiac injury in MI. The exacerbation of cardiac injury was related to the inhibition of generation and differentiation of EPDCs. The alterations in EPDCs were associated with inhibited transition between E-CAD and N-CAD during the epicardial EMT, coupled with the down-regulation of WT1, SNAIL1, and PDGF signaling. In conclusion, this study suggests that Epicardial SMARCA4 plays a critical role in cardiac injury caused by MI, and its regulatory mechanism is related to epicardial EMT. Epicardial SMARCA4 holds potential as a novel molecular target for treating MI.


Asunto(s)
ADN Helicasas , Transición Epitelial-Mesenquimal , Eliminación de Gen , Infarto del Miocardio , Pericardio , Factores de Transcripción , Animales , Infarto del Miocardio/genética , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Transición Epitelial-Mesenquimal/genética , Pericardio/patología , Pericardio/metabolismo , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , ADN Helicasas/genética , ADN Helicasas/metabolismo , Ratones , Diferenciación Celular , Apoptosis/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/deficiencia , Proliferación Celular , Modelos Animales de Enfermedad
4.
J Am Chem Soc ; 146(34): 23978-23988, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39162335

RESUMEN

Reversible lysine acetylation is an important post-translational modification (PTM). This process in cells is typically carried out enzymatically by lysine acetyltransferases and deacetylases. The catalytic lysine in the human kinome is highly conserved and ligandable. Small-molecule strategies that enable post-translational acetylation of the catalytic lysine on kinases in a target-selective manner therefore provide tremendous potential in kinase biology. Herein, we report the first small molecule-induced chemical strategy capable of global acetylation of the catalytic lysine on kinases from mammalian cells. By surveying various lysine-acetylating agents installed on a promiscuous kinase-binding scaffold, Ac4 was identified and shown to effectively acetylate the catalytic lysine of >100 different protein kinases from live Jurkat/K562 cells. In order to demonstrate that this strategy was capable of target-selective and reversible chemical acetylation of protein kinases, we further developed six acetylating compounds on the basis of VX-680 (a noncovalent inhibitor of AURKA). Among them, Ac13/Ac14, while displaying excellent in vitro potency and sustained cellular activity against AURKA, showed robust acetylation of its catalytic lysine (K162) in a target-selective manner, leading to irreversible inhibition of endogenous kinase activity. The reversibility of this chemical acetylation was confirmed on Ac14-treated recombinant AURKA protein, followed by deacetylation with SIRT3 (a lysine deacetylase). Finally, the reversible Ac13-induced acetylation of endogenous AURKA was demonstrated in SIRT3-transfected HCT116 cells. By disclosing the first cell-active acetylating compounds capable of both global and target-selective post-translational acetylation of the catalytic lysine on kinases, our strategy could provide a useful chemical tool in kinase biology and drug discovery.


Asunto(s)
Lisina , Procesamiento Proteico-Postraduccional , Humanos , Acetilación , Lisina/química , Lisina/metabolismo , Células K562 , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Células Jurkat , Proteínas Quinasas/metabolismo , Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Aurora Quinasa A/metabolismo , Aurora Quinasa A/antagonistas & inhibidores , Aurora Quinasa A/química
5.
Opt Express ; 32(9): 15993-16003, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859237

RESUMEN

As the semiconductor technology node continues to shrink, achieving smaller critical dimension in lithography becomes increasingly challenging. Negative tone development (NTD) process is widely employed in advanced node due to their large process window. However, the unique characteristics of NTD, such as shrinkage effect, make the NTD resist model calibration more complex. Gradient descent (GD) and heuristic methods have been applied for calibration of NTD resist model. Nevertheless, these methods depend on initial parameter selection and tend to fall into local optima, resulting in poor accuracy of the NTD model and massive computational time. In this paper, we propose cluster sampling and scalable Bayesian optimization (BO) with constraints method for NTD resist model calibration. This approach utilizes cluster sampling strategy to enhance the capability for global initial sampling and employs scalable BO with constraints for global optimization of high-dimensional parameter space. With this approach, the calibration accuracy is significantly enhanced in comparison with results from GD and heuristic methods, and the computational efficiency is substantially improved compared with GD. By gearing up cluster sampling strategy and scalable BO with constraints, this method offers a new and efficient resist model calibration.

6.
Chemistry ; 30(11): e202303505, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38143237

RESUMEN

The catalysis performance of metal nanoparticles (NPs) will be significantly deteriorated because of their spontaneous agglomeration during practical applications. Covalent-organic frameworks (COFs) materials with functional groups and well-defined channels benefit for the dispersion and anchor of metal ions and the confined growth of metal NPs, working as an ideal platform to compose catalytic systems. In this article, we report a one-pot strategy for the preparation of metal NPs loaded COFs without the need of post-modification. During the polymerization process, the pre-added metal ions were stabilized by the rapidly formed COF oligomers and hardly disturb the construction of COFs. After reduction, metal NPs are uniformly anchored on the COF matrix. Eventually, a wide spectrum of metal NPs, including Au, Pd, Pt, AuPd, CuPd, CuPt and CuPdPt, loaded COFs are successfully prepared. The versatility and metal ions anchoring mechanism are verified with four different COF matrixes. Taking AuPd NPs as example, the resultant AuPd NPs loaded COF materials can selectively decompose ammonium formate and produce hydrogen in-situ, exhibiting over 99 % conversion of hydrodechlorination for chlorobenzenes and nitro-reduction reaction for nitroaromatic compounds under ambient temperature in aqueous solution.

7.
Langmuir ; 40(17): 9001-9011, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38627239

RESUMEN

The enrichment and recovery of gold from wastewater are an alternative method to obtain this noble metal, which benefits reducing hazardous emissions from the conventional ore mining process and reserving natural gold for sustainable development. Inspired by our previous work (Lei et al., Macromol. Rapid Comm. 2022, 2200712), four families of microporous polyureas (mPPUs) with a large surface area (690 m2 g-1) and abundant heteroatom sites have been prepared via the factor-optimized solvothermal protocol. The resultant sample NPU-A starting from 1,5-naphthalene diisocyanate (NDI) and tri(4-aminophenyl) amine (TAPA) exhibits the maximum Au(III) adsorption capacity of 1300 mg g-1 and high selectivity even when the Au(III) concentration is as low as 0.1 mg L-1. This study not only demonstrates the robustness of the high-throughput synthetic strategy but also promotes the investigation of the structure-activity correlation between the mPPU chemical structure and Au(III) adsorption performance.

8.
Int J Legal Med ; 138(5): 2037-2047, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38802694

RESUMEN

In forensic practice, determining the postmortem submersion interval (PMSI) and cause-of-death of cadavers in aquatic ecosystems has always been challenging task. Traditional approaches are not yet able to address these issues effectively and adequately. Our previous study proposed novel models to predict the PMSI and cause-of-death based on metabolites of blood from rats immersed in freshwater. However, with the advance of putrefaction, it is hardly to obtain blood samples beyond 3 days postmortem. To further assess the feasibility of PMSI estimation and drowning diagnosis in the later postmortem phase, gastrocnemius, the more degradation-resistant tissue, was collected from drowned rats and postmortem submersion model in freshwater immediately after death, and at 1 day, 3 days, 5 days, 7 days, and 10 days postmortem respectively. Then the samples were analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the dynamic changes of the metabolites. A total of 924 metabolites were identified. Similar chronological changes of gastrocnemius metabolites were observed in the drowning and postmortem submersion groups. The difference in metabolic profiles between drowning and postmortem submersion groups was only evident in the initial 1 day postmortem, which was faded as the PMSI extension. Nineteen metabolites representing temporally-dynamic patterns were selected as biomarkers for PMSI estimation. A regression model was built based on these biomarkers with random forest algorithm, which yielded a mean absolute error (± SE) of 5.856 (± 1.296) h on validation samples from an independent experiment. These findings added to our knowledge of chronological changes in muscle metabolites from submerged vertebrate remains during decomposition, which provided a new perspective for PMSI estimation.


Asunto(s)
Ahogamiento , Agua Dulce , Inmersión , Metabolómica , Modelos Animales , Músculo Esquelético , Cambios Post Mortem , Animales , Músculo Esquelético/metabolismo , Ahogamiento/diagnóstico , Ahogamiento/metabolismo , Masculino , Cromatografía Liquida , Espectrometría de Masas en Tándem , Ratas , Ratas Sprague-Dawley , Biomarcadores/metabolismo
9.
Environ Sci Technol ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39322606

RESUMEN

Triclocarban (TCC), as a typical antimicrobial agent, accumulates at substantial levels in natural environments and engineered systems. This work investigated the impact of TCC on anaerobic sulfur transformation, especially toxic H2S production. Experimental findings revealed that TCC facilitated sulfur flow from the sludge solid phase to liquid phase, promoted sulfate reduction and sulfur-containing amino acid degradation, and largely improved anaerobic H2S production, i.e., 50-600 mg/kg total suspended solids (TSS) TCC increased the cumulative H2S yields by 24.76-478.12%. Although TCC can be partially biodegraded in anaerobic systems, the increase in H2S production can be mainly attributed to the effect of TCC rather than its degradation products. TCC was spontaneously adsorbed by protein-like substances contained in microbe extracellular polymers (EPSs), and the adsorbed TCC increased the direct electron transfer ability of EPSs, possibly due to the increase in the content of electroactive polymer protein in EPSs, the polarization of the amide group C═O bond, and the increase of the α-helical peptide dipole moment, which might be one important reason for promoting sulfur bioconversion processes. Microbial analysis showed that the presence of TCC enriched the organic substrate-degrading bacteria and sulfate-reducing bacteria and increased the abundances of functional genes encoding sulfate transport and dissimilatory sulfate reduction.

10.
Environ Sci Technol ; 58(18): 8043-8052, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38648493

RESUMEN

Bisphenol A (BPA), as a typical leachable additive from microplastics and one of the most productive bulk chemicals, is widely distributed in sediments, sewers, and wastewater treatment plants, where active sulfur cycling takes place. However, the effect of BPA on sulfur transformation, particularly toxic H2S production, has been previously overlooked. This work found that BPA at environmentally relevant levels (i.e., 50-200 mg/kg total suspended solids, TSS) promoted the release of soluble sulfur compounds and increased H2S gas production by 14.3-31.9%. The tryptophan-like proteins of microbe extracellular polymeric substances (EPSs) can spontaneously adsorb BPA, which is an enthalpy-driven reaction (ΔH = -513.5 kJ mol-1, ΔS = -1.60 kJ mol-1K -1, and ΔG = -19.52 kJ mol-1 at 35 °C). This binding changed the composition and structure of EPSs, which improved the direct electron transfer capacity of EPSs, thereby promoting the bioprocesses of organic sulfur hydrolysis and sulfate reduction. In addition, BPA presence enriched the functional microbes (e.g., Desulfovibrio and Desulfuromonas) responsible for organic sulfur mineralization and inorganic sulfate reduction and increased the abundance of related genes involved in ATP-binding cassette transporters and sulfur metabolism (e.g., Sat and AspB), which promoted anaerobic sulfur transformation. This work deepens our understanding of the interaction between BPA and sulfur transformation occurring in anaerobic environments.


Asunto(s)
Azufre , Azufre/metabolismo , Anaerobiosis , Sulfuro de Hidrógeno/metabolismo , Fenoles/metabolismo , Compuestos de Bencidrilo/metabolismo
11.
Sensors (Basel) ; 24(17)2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39275582

RESUMEN

Simultaneous localization and mapping (SLAM) is an essential component for smart robot operations in unknown confined spaces such as indoors, tunnels and underground. This paper proposes a novel tightly-coupled ranging-LiDAR-inertial simultaneous localization and mapping framework, namely RLI-SLAM, which is designed to be high-accuracy, fast and robust in the long-term fast-motion scenario, and features two key innovations. The first one is tightly fusing the ultra-wideband (UWB) ranging and the inertial sensor to prevent the initial bias and long-term drift of the inertial sensor so that the point cloud distortion of the fast-moving LiDAR can be effectively compensated in real-time. This enables high-accuracy and robust state estimation in the long-term fast-motion scenario, even with a single ranging measurement. The second one is deploying an efficient loop closure detection module by using an incremental smoothing factor graph approach, which seamlessly integrates into the RLI-SLAM system, and enables high-precision mapping in a challenging environment. Extensive benchmark comparisons validate the superior accuracy of the proposed new state estimation and mapping framework over other state-of-the-art systems at a low computational complexity, even with a single ranging measurement and/or in a challenging environment.

12.
Nano Lett ; 23(2): 685-693, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36594847

RESUMEN

While tuning the electronic structure of Pt can thermodynamically alleviate CO poisoning in direct methanol fuel cells, the impact of interactions between intermediates on the reaction pathway is seldom studied. Herein, we contrive a PtBi model catalyst and realize a complete inhibition of the CO pathway and concurrent enhancement of the formate pathway in the alkaline methanol electrooxidation. The key role of Bi is enriching OH adsorbates (OHad) on the catalyst surface. The competitive adsorption of CO adsorbates (COad) and OHad at Pt sites, complementing the thermodynamic contribution from alloying Bi with Pt, switches the intermediate from COad to formate that circumvents CO poisoning. Hence, 8% Bi brings an approximately 6-fold increase in activity compared to pure Pt nanoparticles. This notion can be generalized to modify commercially available Pt/C catalysts by a microwave-assisted method, offering opportunities for the design and practical production of CO-tolerance electrocatalysts in an industrial setting.

13.
J Proteome Res ; 22(3): 802-811, 2023 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-36716354

RESUMEN

Multitarget bioactive molecules (MBMs) are of increasing importance in drug discovery as they could produce high efficacy and a low chance of resistance. Several advanced approaches of quantitative proteomics were developed to accurately identify the protein targets of MBMs, but little study has been carried out in a sequential manner to identify primary protein targets (PPTs) of MBMs. This set of proteins will first interact with MBMs in the temporal order and play an important role in the mode of action of MBMs, especially when MBMs are at low concentrations. Herein, we describe a valuable observation that the result of the enrichment process is highly dependent on concentrations of the probe and the proteome. Interestingly, high concentrations of probe and low concentrations of incubated proteome will readily miss the hyper-reactive protein targets and thereby increase the probability of rendering PPTs with false-negative results, while low concentrations of probe and high concentrations of incubated proteome more than likely will capture the PPTs. Based on this enlightening observation, we developed a proof-of-concept approach to identify the PPTs of iodoacetamide, a thiol-reactive MBM. This study will deepen our understanding of the enrichment process and improve the accuracy of pull-down-guided target identification.


Asunto(s)
Proteoma , Proteoma/metabolismo , Descubrimiento de Drogas
14.
J Am Chem Soc ; 145(48): 26374-26382, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37992232

RESUMEN

The electrochemical conversion of CO2 into multicarbon (C2) products on Cu-based catalysts is strongly affected by the surface coverage of adsorbed CO (*CO) intermediates and the subsequent C-C coupling. However, the increased *CO coverage inevitably leads to strong *CO repulsion and a reduced C-C coupling efficiency, thus resulting in suboptimal CO2-to-C2 activity and selectivity, especially at ampere-level electrolysis current densities. Herein, we developed an atomically ordered Cu9Ga4 intermetallic compound consisting of Cu square-like binding sites interspaced by catalytically inert Ga atoms. Compared to Cu(100) previously known with a high C2 selectivity, the Ga-spaced, square-like Cu sites presented an elongated Cu-Cu distance that allowed to reduce *CO repulsion and increased *CO coverage simultaneously, thus endowing more efficient C-C coupling to C2 products than Cu(100) and Cu(111). The Cu9Ga4 catalyst exhibited an outstanding CO2-to-C2 electroreduction, with a peak C2 partial current density of 1207 mA cm-2 and a corresponding Faradaic efficiency of 71%. Moreover, the Cu9Ga4 catalyst demonstrated a high-power (∼200 W) electrolysis capability with excellent electrochemical stability.

15.
BMC Plant Biol ; 23(1): 188, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37032339

RESUMEN

BACKGROUND: Phosphorus (P) deficiency in desert ecosystems is widespread. Generally, desert species may allocate an enormous proportion of photosynthetic carbon to their root systems to adjust their P-acquisition strategies. However, root P-acquisition strategies of deep-rooted desert species and the coordination response of root traits at different growth stages to differing soil P availability remains unclear. In this study, a two-year pot experiment was performed with four soil P-supply treatments (0, 0.9, 2.8, and 4.7 mg P kg-1 y-1 for the control, low-, intermediate-, and high-P supply, respectively). Root morphological and physiological traits of one- and two-year-old Alhagi sparsifolia seedlings were measured. RESULTS: For two-year-old seedlings, control or low-P supply significantly increased their leaf Mn concentration, coarse and fine roots' specific root length (SRL), specific root surface area (SRSA), and acid phosphatase activity (APase), but SRL and SRSA of one-year-old seedlings were higher under intermediate-P supply treatment. Root morphological traits were closely correlated with root APase activity and leaf Mn concentration. One-year-old seedlings had higher root APase activity, leaf Mn concentration, and root tissue density (RTD), but lower SRL and SRSA. Two-year-old seedlings had higher root APase activity, leaf Mn concentration, SRL and SRSA, but a lower RTD. Root APase activity was significantly positively correlated with the leaf Mn concentration, regardless of coarse or fine roots. Furthermore, root P concentrations of coarse and fine roots were driven by different root traits, with root biomass and carboxylates secretion particularly crucial root traits for the root P-acquisition of one- and two-year-old seedlings. CONCLUSIONS: Variation of root traits at different growth stages are coordinated with root P concentrations, indicating a trade-off between root traits and P-acquisition strategies. Alhagi sparsifolia developed two P-activation strategies, increasing P-mobilizing phosphatase activity and carboxylates secretion, to acclimate P-impoverished in soil. The adaptive variation of root traits at different growth stages and diversified P-activation strategies are conducive to maintaining the desert ecosystem productivity.


Asunto(s)
Ecosistema , Fabaceae , Fósforo , Suelo , Raíces de Plantas , Plantas , Plantones , Ácidos Carboxílicos
16.
Chemistry ; 29(16): e202203142, 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36565275

RESUMEN

Enhancing catalytic performance as well as reducing catalyst cost are the eternal pursuit for the catalysis community. Herein, a simple and effective palladium-doped cobalt (Pd/Co) catalyst with high Pd atom utilization efficiency was synthesized via galvanic replacement reaction for the selective hydrogenation of nitrobenzene with H2 at room temperature, delivering >99 % yield of aniline with up to 158 times higher catalytic activity than commercial palladium powder. Detailed characterizations and DFT calculations revealed that Co-Pd interaction leads to a decrease in electron density of Pd and the distance between Pd atoms that results in the enhanced catalytic performance. Further experiments indicated that the Pd/Co catalyst serves as a highly efficient, selective, and recyclable catalyst for a range of nitroarene substrates. This work might provide a green and sustainable methodology to design and synthesize highly active catalysts with high utilization efficiency of the noble metals in fundamental and applied research.

17.
J Org Chem ; 88(7): 4359-4371, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-36939669

RESUMEN

Herein, hypervalent iodine-catalyzed halogenation of aryl-activated alkenes using BX3 (X = Cl, Br) as the halogen source and activating reagents was reported. Various halogenated 1,3-oxazine/2-oxazoline derivatives were obtained in good-to-high yields. Using BF3 resulted in different substitute sites from BBr3 and BCl3 of the products, indicating different reactive intermediates and reaction pathways. The reaction underwent a "ligand coupling/oxidative addition/intermolecular nucleophilic attack/1,2-aryl migration/reductive elimination/intramolecular nucleophilic attack" cascade when BF3 was applied as the halogen source, while 1,2-aryl migration has "disappeared" when the halogen source was BBr3 or BCl3. Possible catalytic cycles were proposed, and DFT calculations were conducted to demonstrate the differences among BX3 (X = F, Cl, Br) in the hypervalent iodine-catalyzed halogenations.

18.
Cell Biol Toxicol ; 39(4): 1433-1452, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36121554

RESUMEN

T helper (Th) 17 cells highly contribute to the immunopathology of rheumatoid arthritis. Morin, a natural flavonoid, owns well anti-arthritic action but unclear effect on Th17 differentiation. This study tried to solve this issue and explore the mechanisms in view of cellular metabolism. Naïve CD4+ T cells were treated with anti-CD3/CD28 along with Th17-inducing cytokines. Morin was shown to block Th17 differentiation without affecting cell viability even when Foxp3 was dampened. The mechanisms were ascribed to the limited fatty acid synthesis by restricting FASN transcription, as indicated by metabolomics analysis, nile red staining, detection of triglycerides, FASN overexpression, and addition of palmitic acid. Moreover, morin had slight effect on cell apoptosis and protein palmitoylation during Th17 differentiation, but blocked the binding of RORγt to promoter and CNS2 region of Il17a gene. Oleic acid rescued the inhibition of morin on RORγt function, and Th17-inducing cytokines could not induce RORγt function in SCD1-defficient cells, suggesting that oleic acid but not palmitic acid was the direct effector in the action of morin. Then, PPARγ was identified as the target of morin, and GW9662 or PPARγ CRISPR/Cas9 KO plasmid weakened its above-mentioned effects. The transrepression of FASN by morin was owing to physical interaction between PPARγ and Sp1, and the importance of Sp1 in Th17 differentiation was confirmed by siSp1. Finally, the effects and mechanisms for morin-dampened Th17 responses were confirmed in collagen-induced arthritis (CIA) mice. Collectively, morin inhibited Th17 differentiation and alleviated CIA by limiting fatty acid synthesis subsequent to PPARγ activation.


Asunto(s)
Artritis Experimental , Ratones , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/metabolismo , Artritis Experimental/patología , PPAR gamma/metabolismo , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares , Agonistas de PPAR-gamma , Ácido Oléico , Diferenciación Celular , Citocinas , Flavonoides/farmacología
19.
Arch Toxicol ; 97(2): 441-456, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36336710

RESUMEN

Cisplatin is recommended as a first-line chemotherapeutic agent against advanced non-small cell lung cancer (NSCLC), but acquired resistance substantially limits its clinical efficacy. Recently, DNA methylation has been identified as an essential contributor to chemoresistance. However, the precise DNA methylation regulatory mechanism of cisplatin resistance remains unclear. Here, we found that nicotinamide nucleotide transhydrogenase (NNT) was silenced by DNA hypermethylation in cisplatin resistance A549 (A549/DDP) cells. Also, the DNA hypermethylation of NNT was positively correlated to poor prognosis in NSCLC patients. Overexpression of NNT in A549/DDP cells could reduce their cisplatin resistance, and also suppressed their tumor malignancy such as cell proliferation and clone formation. However, NNT enhanced sensitivity of A549/DDP cells to cisplatin had little to do with its function in mediating NADPH and ROS level, but was mainly because NNT could inhibit protective autophagy in A549/DDP cells. Further investigation revealed that NNT could decrease NAD+ level, thereby inactivate SIRT1 and block the autophagy pathway, while re-activation of SIRT1 through NAD+ precursor supplementation could antagonize this effect. In addition, targeted demethylation of NNT CpG island via CRISPR/dCas9-Tet1 system significantly reduced its DNA methylation level and inhibited the autophagy and cisplatin resistance in A549/DDP cells. Thus, our study found a novel chemoresistance target gene NNT, which played important roles in cisplatin resistance of lung cancer cells. Our findings also suggested that CRISPR-based DNA methylation editing of NNT could be a potential therapeutics method in cisplatin resistance of lung cancer.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , NADP Transhidrogenasas , Humanos , Células A549 , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Autofagia , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Proliferación Celular , Cisplatino/farmacología , ADN , Metilación de ADN , Resistencia a Antineoplásicos/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , NAD/metabolismo , NADP Transhidrogenasas/genética , NADP Transhidrogenasas/metabolismo , Sirtuina 1/metabolismo
20.
Appl Opt ; 62(33): 8769-8779, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-38038022

RESUMEN

As the feature size of integrated circuits continues to decrease, optical proximity correction (OPC) has emerged as a crucial resolution enhancement technology for ensuring high printability in the lithography process. Recently, level set-based inverse lithography technology (ILT) has drawn considerable attention as a promising OPC solution, showcasing its powerful pattern fidelity, especially in advanced processing. However, the massive computational time consumption of ILT limits its applicability to mainly correcting partial layers and hotspot regions. Deep learning (DL) methods have shown great potential in accelerating ILT. However, the lack of domain knowledge of inverse lithography limits the ability of DL-based algorithms in process window (PW) enhancement, etc. In this paper, we propose an inverse lithography physics-informed deep neural level set (ILDLS) approach for mask optimization. This approach utilizes level set-based ILT as a layer within the DL framework and iteratively conducts mask prediction and correction to significantly enhance printability and PW in comparison with results from pure DL and ILT. With this approach, the computational efficiency is significantly improved compared with ILT. By gearing up DL with the knowledge of inverse lithography physics, ILDLS provides a new and efficient mask optimization solution.

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