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1.
Small Methods ; : e2400643, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39161085

RESUMEN

Additive engineering has emerged as a promising strategy to address the inherent instability challenges of perovskite solar cells (PSCs) in the pursuit of commercial viability. However, achieving multifunctionality using a singular additive remains a considerable challenge. In this study, a novel comb-like multifunctional perfluoroalkyl-g-polyethylenimmonium iodide (FPEI·HI) as additives to the PbI2 precursor solution to facilitate the formation of high-quality and water-resistant perovskite films is presented. FPEI·HI establishes robust interactions with both formamidinium iodide (FAI) and PbI2, mediated by hydrogen bonding and Lewis acid-base interactions. These interactions play a pivotal role in simultaneously passivating negative and positive charged defects within the perovskite structure. Furthermore, the inclusion of perfluoroalkyl chains serves as resilience against moisture intrusion. As a consequence of these effects, a notably high device efficiency of 24.29% is achieved, demonstrating comprehensive improvement in various photovoltaic parameters compared to the control device (22.51%). Notably, unencapsulated devices exhibit remarkable stability in high-humidity environments, retaining 90% of their initial efficiency even after 2500 h of storage. This work underscores the efficacy of FPEI·HI as a critical enabler for enhancing the stability and efficiency of perovskite solar cells, marking a significant stride toward their commercialization.

2.
Front Nutr ; 11: 1428577, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39139650

RESUMEN

Introduction: This study aimed to investigate the regulatory effects of mulberry leaf flavonoids and carnosic acid complex (MCC) on the growth performance, intestinal morphology, antioxidant, and p38 MAPK/Nrf2 pathway in broilers. Methods: A total of 256 healthy 8-day-old female yellow-feathered broilers were randomly divided into 4 equal groups: a control group (CON) fed a basal diet, an antibiotic group (CTC) supplemented with 50 mg/kg chlortetracycline, and two experimental groups (MCC75, MCC150) fed basal diets with 75 mg/kg and 150 mg/kg of MCC, respectively. The experiment lasted for 56 days, with days 1-28 designated as the initial phase and days 29-56 as the growth phase. Results: The results on the growth performance showed that diets supplemented with MCC and CTC decreased the feed-to-gain ratio (F/G), diarrhea rate, and death rate, while significantly increasing the average daily weight gain (ADG) (p < 0.05). Specifically, the MCC150 group enhanced intestinal health, indicated by reduced crypt depth and increased villus height-to-crypt depth ratio (V/C) as well as amylase activity in the jejunum. Both the MCC and CTC groups exhibited increased villus height and V/C ratio in the ileal (p < 0.05). Additionally, all treated groups showed elevated serum total antioxidant capacity (T-AOC), and significant increases in catalase (CAT) and glutathione peroxidase (GSH-Px) activities were observed in both the MCC150 and CTC groups. Molecular analysis revealed an upregulation of the jejunal mRNA expression levels of PGC-1α, Nrf2, and Keap1 in the MCC and CTC groups, as well as an upregulation of ileum mRNA expression levels of P38, PGC-1α, Nrf2, and Keap1 in the MCC150 group, suggesting activation of the p38-MAPK/Nrf2 pathway. Discussion: These findings indicate that dietary supplementation with MCC, particularly at a dosage of 150 mg/kg, may serve as a viable antibiotic alternative, enhancing growth performance, intestinal health, and antioxidant capacity in broilers by regulating the p38-MAPK/Nrf2 pathway.

3.
Phytochem Anal ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38957046

RESUMEN

INTRODUCTION: Sophora flavescens Aiton (Fabaceae), a ubiquitous plant species in Asia, contains a wide range of pharmacologically active compounds, such as flavonoids, with potential anti-Alzheimer's disease (anti-AD) effects. OBJECTIVES: The objective of the study is to develop a quaternity method for the screening, isolation, extraction optimization, and activity evaluation of acetylcholinesterase (AChE)-inhibiting compounds from S. flavescens to realize high-throughput screening of active substances in traditional Chinese medicine and to provide experimental data for the development of anti-AD drugs. METHODS: With AChE as the target molecule, affinity ultrafiltration and liquid chromatography-mass spectrometry were applied to screen for potential inhibitors of the enzyme in S. flavescens. Orthogonal array experiments combined with the multi-objective Non-Dominated Sorting Genetic Algorithm III was used for the first time to optimize the process for extracting the active substances. Enzyme inhibition kinetics and molecular docking studies were performed to verify the potential anti-AD effects of the active compounds. RESULTS: Five AChE-inhibiting compounds were identified: kushenol I, kurarinone, sophoraflavanone G, isokurarinone, and kushenol E. These were successfully separated at purities of 72.88%, 98.55%, 96.86%, 96.74%, and 95.84%, respectively, using the n-hexane/ethyl acetate/methanol/water (4.0/5.0/4.0/5.0, v/v/v/v), n-hexane/ethyl acetate/methanol/water (5.0/5.0/6.0/4.0, v/v/v/v), and n-hexane/ethyl acetate/methanol/water (4.9/5.1/5.7/4.3, v/v/v/v) mobile phase systems. Enzyme inhibition kinetics revealed that kushenol E had the best inhibitory effect. CONCLUSION: This study elucidates the mechanism of action of five active AChE inhibitors in S. flavescens and provides a theoretical basis for the screening and development of anti-AD and other therapeutic drugs.

4.
Cancers (Basel) ; 16(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39001551

RESUMEN

The development of cancer involves the accumulation of somatic mutations in several essential biological pathways. Delineating the temporal order of pathway mutations during tumorigenesis is crucial for comprehending the biological mechanisms underlying cancer development and identifying potential targets for therapeutic intervention. Several computational and statistical methods have been introduced for estimating the order of somatic mutations based on mutation profile data from a cohort of patients. However, one major issue of current methods is that they do not take into account intra-tumor heterogeneity (ITH), which limits their ability to accurately discern the order of pathway mutations. To address this problem, we propose PATOPAI, a probabilistic approach to estimate the temporal order of mutations at the pathway level by incorporating ITH information as well as pathway and functional annotation information of mutations. PATOPAI uses a maximum likelihood approach to estimate the probability of pathway mutational events occurring in a specific sequence, wherein it focuses on the orders that are consistent with the phylogenetic structure of the tumors. Applications to whole exome sequencing data from The Cancer Genome Atlas (TCGA) illustrate our method's ability to recover the temporal order of pathway mutations in several cancer types.

5.
Pest Manag Sci ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007292

RESUMEN

BACKGROUND: Unmanned aerial vehicles (UAVs) for pesticide application show promising potential in tobacco pest management. However, the impact of flight parameters on spray efficacy requires further investigation. Three field experiments were conducted from the rosette to the maturation stage of tobacco to systematically assess spray efficacy under varying flight heights, speeds, and application volumes. Using a multi-index weight analysis method, optimal operational parameter combinations for different tobacco growth stages were evaluated and compared with backpack electric sprayers. RESULTS: For the rosette stage, the recommended parameter is a flight speed of 5 m s-1, a flight height of 2 m, and a liquid application volume of 30 L hm-2; during the vigorous growth stage, the suggested parameter includes a flight speed of 3 m s-1, a flight height of 2 m, and a liquid application volume of 22.5 L hm-2. In the maturing stage, optimal parameter consists of a flight speed of 3 m s-1, a flight height of 3.5 m, and a liquid application volume of 30 L hm-2. Furthermore, UAV spraying achieves higher droplet deposition on both sides of tobacco leaves compared to traditional electric backpack sprayers. CONCLUSIONS: Adjusting UAV spraying parameters for different tobacco growth stages is crucial. These results can provide the methods for the precise control technology of tobacco pests at different growth stages. © 2024 Society of Chemical Industry.

6.
ACS Appl Mater Interfaces ; 16(24): 31114-31125, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38857487

RESUMEN

Albeit the undesirable attributes of NiOx, such as low conductivity, unmanageable defects, and redox reactions occurring at the perovskite/NiOx interface, which impede the progress in inverted perovskite solar cells (i-PSCs), it is the most favorable choice of technology for industrialization of PSCs. In this study, we propose a novel Ni vacancy defect modulate approach to leverage the conformal growth and surface self-limiting reaction characteristics of the atomic layer deposition (ALD)-fabricated NiOx by varying the O2 plasma injection time (tOE) to induce self-doping. Consequently, NiOx thin films with enhanced conductivity, an appropriate Ni3+/Ni2+ ratio, stable surface states, and ultrathinness are realized as hole-transporting layers (HTLs) in p-i-n PSCs. As a result of these improvements, ALD-NiOx-based devices exhibit the highest power conversion efficiency (PCE) of 19.86% and a fill factor (FF) of 81.86%. Notably, the optimal interfacial defects effectively suppressed the severe reaction between the perovskite and NiOx. This suppression is evidenced by the lowest decay rate observed in a harsh environment, lasting for 500 consecutive hours. The proposed approach introduces the possibility of a hierarchical distribution of defects and offers feasibility for the fabrication of large-area, uniform, and high-quality films.

7.
Nat Commun ; 15(1): 4300, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773134

RESUMEN

The chromatin modifier GRAIN WEIGHT 6a (GW6a) enhances rice grain size and yield. However, little is known about its gene network determining grain size. Here, we report that MITOGEN-ACTIVED PROTEIN KINASE 6 (OsMAPK6) and E3 ligase CHANG LI GENG 1 (CLG1) interact with and target GW6a for phosphorylation and ubiquitylation, respectively. Unexpectedly, however, in vitro and in vivo assays reveal that both of the two post-translational modifications stabilize GW6a. Furthermore, we uncover two major GW6a phosphorylation sites (serine142 and threonine186) targeted by OsMAPK6 serving an important role in modulating grain size. In addition, our genetic and molecular results suggest that the OsMAPK6-GW6a and CLG1-GW6a axes are crucial and operate in a non-additive manner to control grain size. Overall, our findings identify a previously unknown mechanism by which phosphorylation and ubiquitylation non-additively stabilize GW6a to enhance grain size, and reveal correlations and interactions of these posttranslational modifications during rice grain development.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Ubiquitinación , Oryza/metabolismo , Oryza/genética , Oryza/crecimiento & desarrollo , Fosforilación , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Grano Comestible/metabolismo , Grano Comestible/crecimiento & desarrollo , Procesamiento Proteico-Postraduccional , Plantas Modificadas Genéticamente , Cromatina/metabolismo
8.
Small ; 20(37): e2402531, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38727180

RESUMEN

The efficacy of electron transport layers (ETLs) is pivotal for optimizing the device performance of perovskite photovoltaic applications. However, colloidal dispersions of SnO2 are prone to aggregation and possess structural defects, such as terminal-hydroxyls (OHT) and oxygen vacancies (VOs), which can degrade the quality of ETLs, impede charge extraction and transport, and affect the nucleation and growth processes of the perovskite layer. In this study, the Sb(OH)4 - ions hydrolyzed from SbCl3 in colloidal dispersion can bind to defect sites and effectively stabilize the SnO2 nanocrystals are demonstrated. Upon oxidative annealing, a Sb2O5@SnO2 composite film is formed, in which the Sb2O5 not only mitigates the aforementioned defects but also broadens the energy range of unoccupied states through its dispersed conduction band. The increased electron affinity (EA) facilitates more efficient capture of photoexcited electrons from the perovskite layer, thus augmenting electron extraction and minimizing electron-hole recombination. As a result, a significant improvement in power conversion efficiency (PCE) from 22.60% to 24.54% is achieved, with an open circuit voltage (VOC) of up to 1.195 V, along with excellent stability of unsealed devices under various conditions. This study provides valuable insights for the understanding and design of ETLs in perovskite photovoltaic applications.

9.
Plant Biotechnol J ; 22(9): 2558-2574, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38685729

RESUMEN

Spartina alterniflora is an exo-recretohalophyte Poaceae species that is able to grow well in seashore, but the genomic basis underlying its adaptation to salt tolerance remains unknown. Here, we report a high-quality, chromosome-level genome assembly of S. alterniflora constructed through PacBio HiFi sequencing, combined with high-throughput chromosome conformation capture (Hi-C) technology and Illumina-based transcriptomic analyses. The final 1.58 Gb genome assembly has a contig N50 size of 46.74 Mb. Phylogenetic analysis suggests that S. alterniflora diverged from Zoysia japonica approximately 21.72 million years ago (MYA). Moreover, whole-genome duplication (WGD) events in S. alterniflora appear to have expanded gene families and transcription factors relevant to salt tolerance and adaptation to saline environments. Comparative genomics analyses identified numerous species-specific genes, significantly expanded genes and positively selected genes that are enriched for 'ion transport' and 'response to salt stress'. RNA-seq analysis identified several ion transporter genes including the high-affinity K+ transporters (HKTs), SaHKT1;2, SaHKT1;3 and SaHKT1;8, and high copy number of Salt Overly Sensitive (SOS) up-regulated under high salt conditions, and the overexpression of SaHKT2;4 in Arabidopsis thaliana conferred salt tolerance to the plant, suggesting specialized roles for S. alterniflora to adapt to saline environments. Integrated metabolomics and transcriptomics analyses revealed that salt stress activate glutathione metabolism, with differential expressions of several genes such as γ-ECS, GSH-S, GPX, GST and PCS in the glutathione metabolism. This study suggests several adaptive mechanisms that could contribute our understanding of evolutional basis of the halophyte.


Asunto(s)
Genoma de Planta , Filogenia , Poaceae , Tolerancia a la Sal , Tolerancia a la Sal/genética , Genoma de Planta/genética , Poaceae/genética , Poaceae/metabolismo , Plantas Tolerantes a la Sal/genética , Plantas Tolerantes a la Sal/metabolismo , Regulación de la Expresión Génica de las Plantas
10.
Front Plant Sci ; 15: 1384246, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601316

RESUMEN

Introduction: Salt tolerance during seed germination is an important trait for direct seeding and low-cost rice production. Nevertheless, it is still not clear how seed germination under salt stress is regulated genetically. Methods: In this study, genome-wide association studies (GWAS) were performed to decipher the genetic basis of seed germination under salt stress using 541 rice varieties collected worldwide. Results and discussion: Three quantitative trait loci (QTLs) were identified including qGRG3-1 on chromosome 3, qGRG3-2 on chromosome 5, and qGRG4 on chromosome 4. Assessment of candidate genes in these loci for their responses to salt stress identified a TATA modulatory factor (OsTMF) in qGRG3-2. The expression of OsTMF was up-regulated in both roots and shoots after exposure to salt stress, and OsTMF knockout mutants exhibited delayed seed germination under salt stress. Haplotype analysis showed that rice varieties carrying OsTMF-Hap2 displayed elevated salt tolerance during seed germination. These results provide important knowledge and resources to improve rice seed germination under salt stress in the future.

11.
Cancers (Basel) ; 16(7)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38611076

RESUMEN

Cancer cells undergo a significant level of "metabolic reprogramming" or "remodeling" to ensure an adequate supply of ATP and "building blocks" for cell survival and to facilitate accelerated proliferation. Cancer cells preferentially use glycolysis for ATP production (the Warburg effect); however, cancer cells, including colorectal cancer (CRC) cells, also depend on oxidative phosphorylation (OXPHOS) for ATP production, a finding that suggests that both glycolysis and OXPHOS play significant roles in facilitating cancer progression and proliferation. Our prior studies identified a semisynthetic isoflavonoid, DBI-1, that served as an AMPK activator targeting mitochondrial complex I. Furthermore, DBI-1 and a glucose transporter 1 (GLUT1) inhibitor, BAY-876, synergistically inhibited CRC cell growth in vitro and in vivo. We now report a study of the structure-activity relationships (SARs) in the isoflavonoid family in which we identified a new DBI-1 analog, namely, DBI-2, with promising properties. Here, we aimed to explore the antitumor mechanisms of DBIs and to develop new combination strategies by targeting both glycolysis and OXPHOS. We identified DBI-2 as a novel AMPK activator using an AMPK phosphorylation assay as a readout. DBI-2 inhibited mitochondrial complex I in the Seahorse assays. We performed proliferation and Western blotting assays and conducted studies of apoptosis, necrosis, and autophagy to corroborate the synergistic effects of DBI-2 and BAY-876 on CRC cells in vitro. We hypothesized that restricting the carbohydrate uptake with a KD would mimic the effects of GLUT1 inhibitors, and we found that a ketogenic diet significantly enhanced the therapeutic efficacy of DBI-2 in CRC xenograft mouse models, an outcome that suggested a potentially new approach for combination cancer therapy.

12.
J Sep Sci ; 47(5): e2300647, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38466162

RESUMEN

Accurate screening and targeted preparative isolation of active substances in natural medicines have long been two technical challenges in natural medicine research. This study outlines a new approach to improve the efficiency of natural product preparation, focusing on rapidly and accurately screening potential active ingredients in Inonotus obliquus as well as efficiently preparing 5-lipoxidase (5-LOX) inhibitors, to provide new ideas for the treatment of asthma with Inonotus obliquus. First, we used ultrafiltration (UF) mass spectrometry to screen for three potential inhibitors of 5-LOX in Inonotus obliquus. Subsequently, the inhibitory effect of the active ingredients screened in the UF assay on 5-LOX was verified using the molecular docking technique, and the potential role of the active compounds in Inonotus obliquus for the treatment of asthma was analyzed by network pharmacology. Finally, based on the above activity screening guidelines, we used semi-preparative liquid chromatography and consecutive high-speed countercurrent chromatography to isolate three high-purity 5-LOX inhibitors such as betulin, lanosterol, and quercetin. Obviously, through the above approach, we have seamlessly combined rapid discovery, screening, and centralized preparation of the active ingredient with molecular-level interactions between the active ingredient and the protease.


Asunto(s)
Asma , Inhibidores de la Lipooxigenasa , Inhibidores de la Lipooxigenasa/farmacología , Simulación del Acoplamiento Molecular , Inonotus , Asma/tratamiento farmacológico
13.
Angew Chem Int Ed Engl ; 63(21): e202402904, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38527959

RESUMEN

Despite the remarkable progress of perovskite solar cells (PSCs), challenges remain in terms of finding effective and viable strategies to enhance their long-term stability while maintaining high efficiency. In this study, a new insulating and hydrophobic fluorinated polyimide (FPI: 6FDA-6FAPB) was used as the interface layer between the perovskite layer and the hole transport layer (HTL) in PSCs. The functional groups of FPI play a pivotal role in passivating interface defects within the device. Due to its high work function, FPI demonstrates field-effect passivation (FEP) capabilities as an interface layer, effectively mitigating non-radiative recombination at the interface. Notably, the FPI insulating interface layer does not impede carrier transmission at the interface, which is attributed to the presence of hole tunneling effects. The optimized PSCs achieve an outstanding power conversion efficiency (PCE) of 24.61 % and demonstrate excellent stability, showcasing the efficacy of FPI in enhancing device performance and reliability.

14.
Fitoterapia ; 175: 105856, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38354820

RESUMEN

Poria cocos (Schw.) Wolf (P. cocos) has been widely used as medical plant in East Asia with remarkable anti-Alzheimer's disease (anti-AD) activity. However, the underlying mechanisms are still confused. In this study, based on the ß-Amyloid deposition hypothesis of AD, an integrated analysis was conducted to screen and separation 5-lipoxygenase (5-LOX) inhibitors from triterpenoids of P. cocos and investigate the anti-AD mechanisms, containing bioaffinity ultrafiltration UPLC-Q-Exactive, molecular docking, and multiple complex networks. Five triterpenoids were identified as potential 5-LOX inhibitors, including Tumulosic acid, Polyporenic acid C, 3-Epi-dehydrotumulosic acid, Pachymic acid and Dehydrotrametenolic acid. Five potential 5-LOX inhibitors were screened by ultrafiltration affinity assay in P. cocos. The molecular docking simulation results are consistent with the ultrafiltration experimental results, which further verifies the accuracy of the experiment. The commercial 5-LOX inhibitor that Zileuton was used as a positive control to evaluate the inhibitory effect of active ingredients on 5-LOX. Subsequently, the established separation method allowed the five active ingredients (Pachymic acid, 3-Epi-dehydrotumulosic acid, Dehydrotrametenolic acid, Tumulosic acid and Polyporenic acid C) with high purity to be isolated. Targeting network pharmacology analysis showed that five active ingredients correspond to a total of 286 targets. Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis found that target cells were mainly enriched in Pathways in cancer, Lipid and atherosclerosis. Our results indicate that P. cocos extract has the potential to be used in the prevention and treatment of neurodegenerative diseases. This will help elucidate the mechanisms of action of various medicinal plants at the molecular level and provide more opportunities for the discovery and development of new potential treatments from health food resources.


Asunto(s)
Inhibidores de la Lipooxigenasa , Simulación del Acoplamiento Molecular , Triterpenos , Wolfiporia , Triterpenos/farmacología , Triterpenos/aislamiento & purificación , Triterpenos/química , Inhibidores de la Lipooxigenasa/farmacología , Inhibidores de la Lipooxigenasa/aislamiento & purificación , Wolfiporia/química , Estructura Molecular , Ultrafiltración , Araquidonato 5-Lipooxigenasa/metabolismo , Cromatografía Líquida de Alta Presión , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Plantas Medicinales/química , Farmacología en Red
15.
Phytochem Anal ; 35(3): 599-616, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38287705

RESUMEN

INTRODUCTION: Accurate screening and targeted preparative isolation of active substances from natural medicines have long been technical challenges in natural medicine research. OBJECTIVES: This study outlines a new approach for improving the efficiency of natural product preparation, focusing on the rapid and accurate screening of potential active ingredients in Ganoderma lucidum and efficient preparation of lipoxidase inhibitors, with the aim of providing new ideas for the treatment of Alzheimer's disease with G. lucidum. METHODS: The medicinal plant G. lucidum was selected through ultrafiltration coupled with liquid chromatography and mass spectrometry (UF-LC-MS) and computer-assisted screening for lipoxygenase (LOX) inhibitors. In addition, the inhibitory effect of the active compounds on LOX was studied using enzymatic reaction kinetics, and the underlying mechanism is discussed. Finally, based on the earlier activity screening guidelines, the identified ligands were isolated and purified through complex chromatography (high-speed countercurrent chromatography and semi-preparative high-performance liquid chromatography). RESULTS: Five active ingredients, ganoderic acids A, B, C2, D2, and F, were identified and isolated from G. lucidum. We improved the efficiency and purity of active compound preparation using virtual computer screening and enzyme inhibition assays combined with complex chromatography. CONCLUSION: The innovative methods of UF-LC-MS, computer-aided screening, and complex chromatography provide powerful tools for screening and separating LOX inhibitors from complex matrices and provide a favourable platform for the large-scale production of bioactive substances and nutrients.


Asunto(s)
Antineoplásicos , Reishi , Inhibidores de la Lipooxigenasa/farmacología , Cromatografía Líquida de Alta Presión , Distribución en Contracorriente
16.
J Phys Chem Lett ; 15(3): 717-724, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38214912

RESUMEN

We report the in operando visualization of the photocatalytic turnovers on single eosin Y (EY) through a redox-induced photoblinking phenomenon. The photocatalytic cyclization of thiobenzamide (TB) catalyzed by EY was investigated. The analysis of the intensity-versus-time trajectories of single EYs revealed the kinetics and dynamics of the elementary photocatalytic turnovers and the heterogeneity of the activity of individual EYs. The quenching turnover time showed a fast population and a slow population, which could be attributed to the singlet and triplet states of photoexcited EY. The slow quenching turnovers were more dominant at higher TB concentrations. The activity heterogeneity of EYs was studied over a series of reactant concentrations. Excess quenching reagent was found to decrease the percentage of active EYs. The method can be broadly applied to studying the elementary processes of photocatalytic organic reactions in operando.

17.
Int Immunopharmacol ; 126: 111153, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37979451

RESUMEN

To investigate the regulatory effects of Chito-oligosaccharide (COS) on the anti-oxidative, anti-inflammatory, and MAPK signaling pathways. A total of 40 28-day-old weaned piglets were randomly allotted to 4 equal groups [including the control group, lipopolysaccharide (LPS) group, COS group, and COS*LPS group]. On the morning of d 14 and 21, piglets were injected with saline or LPS. At 2 h post-injection, whole blood samples were collected on d 14 and 21, and small intestine and liver samples were collected and analyzed on d 21. The results showed that COS inhibited the LPS-induced increase of malondialdehyde (MDA) concentration and hepatic TNF-α cytokines. COS significantly increased the serum total antioxidant capability (T-AOC) value on d 14, and total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) activities in both serum and liver on d 21. Furthermore, it increased hepatic catalase (CAT) activity. COS also increased the LPS-induced decrease in serum IgG concentrations. Immunohistochemical analysis results showed that COS significantly increased the jejunal and ileal Caspase 3, and ileal CD4+ values challenged by LPS. Dietary COS decreased the LPS-induced jejunal and ileal BAX and CCL2 mRNA levels, markedly decreased ileal COX2 and SOD1 mRNA levels, while increasing ileal iNOS. Furthermore, COS significantly increased the LPS-induced jejunal and ileal p-P38 and MyD88, as well as jejunal P38, while it effectively suppressed jejunal JNK1, and jejunal and ileal JNK2, p-JNK1, and p-JNK2 protein expressions. These results demonstrated that COS could be beneficial by attenuating LPS-challenged intestinal inflammation via regulating mitochondrial apoptotic and MAPK signaling pathways.


Asunto(s)
Lipopolisacáridos , Transducción de Señal , Animales , Porcinos , Lipopolisacáridos/farmacología , Antioxidantes/metabolismo , ARN Mensajero/metabolismo , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Oligosacáridos , Suplementos Dietéticos/análisis
18.
Phytochem Anal ; 35(1): 116-134, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37798938

RESUMEN

INTRODUCTION: Studies show that Polyporus umbellatus has some pharmacological effects in enhancing immunity and against gout. OBJECTIVES: We aimed to establish new techniques for extraction, biological activity screening, and preparation of xanthine oxidase inhibitors (XODIs) from P. umbellatus. METHODS: First, the extraction of P. umbellatus was investigated using the back propagation (BP) neural network genetic algorithm mathematical regression model, and the extraction variables were optimised to maximise P. umbellatus yield. Second, XODIs were rapidly screened using ultrafiltration, and the change of XOD activity was tested by enzymatic reaction kinetics experiment to reflect the inhibitory effect of active compounds on XOD. Meanwhile, the potential anti-gout effects of the obtained active substances were verified using molecular docking, molecular dynamics simulations, and network pharmacology analysis. Finally, with activity screening as guide, a high-speed countercurrent chromatography (HSCCC) method combined with consecutive injection and two-phase solvent system preparation using the UNIFAC mathematical model was successfully developed for separation and purification of XODIs, and the XODIs were identified using MS and NMR. RESULTS: The results verified that polyporusterone A, polyporusterone B, ergosta-4,6,8(14),22-tetraen-3-one, and ergosta-7,22-dien-3-one of P. umbellatus exhibited high biological affinity towards XOD. Their structures have been further identified by NMR, indicating that the method is effective and applicable for rapid screening and identification of XODIs. CONCLUSION: This study provides new ideas for the search for natural XODIs active ingredients, and the study provide valuable support for the further development of functional foods with potential therapeutic benefits.


Asunto(s)
Polyporus , Xantina Oxidasa , Simulación del Acoplamiento Molecular , Polyporus/química , Inhibidores Enzimáticos/farmacología
19.
Nat Chem ; 16(2): 210-217, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37945834

RESUMEN

Microscopic sequences of synthetic polymers play crucial roles in the polymer properties, but are generally unknown and inaccessible to traditional measurements. Here we report real-time optical sequencing of single synthetic copolymer chains under living polymerization conditions. We achieve this by carrying out multi-colour imaging of polymer growth by single catalysts at single-monomer resolution using CREATS (coupled reaction approach toward super-resolution imaging). CREATS makes a reaction effectively fluorogenic, enabling single-molecule localization microscopy of chemical reactions at higher reactant concentrations. Our data demonstrate that the chain propagation kinetics of surface-grafted polymerization contains temporal fluctuations with a defined memory time (which can be attributed to neighbouring monomer interactions) and chain-length dependence (due to surface electrostatic effects). Furthermore, the microscopic sequences of individual copolymers reveal their tendency to form block copolymers, and, more importantly, quantify the size distribution of individual blocks for comparison with theoretically random copolymers. Such sequencing capability paves the way for single-chain-level structure-function correlation studies of synthetic polymers.

20.
J Sep Sci ; 47(1): e2300505, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38135883

RESUMEN

Poria Cum Radix Pini is a rare medicinal fungus that contains several potential therapeutic ingredients. On this basis, a particle swarm mathematical model was used to optimize the extraction process of total triterpenes from P. Cum Radix Pini, and xanthine oxidase inhibitors were screened using affinity ultrafiltration mass spectrometry. Meanwhile, the accuracy of the ultrafiltration assay was verified by molecular docking experiments and molecular dynamics analysis, and the mechanism of action of the active compounds for the treatment of gout was analyzed by enzymatic reaction kinetics and network pharmacology. A high-speed countercurrent chromatography method combined with the consecutive injection and the economical two-phase solvent system preparation using functional activity coefficient of universal quasichemical model (UNIFAC) mathematical model was developed for increasing the yield of target compound. In addition, dehydropachymic acid and pachymic acid were used as competitive inhibitors, and 3-O-acetyl-16alpha-hydroxydehydrotrametenolic acid and dehydrotrametenolic acid were used as mixed inhibitors. Then, activity-oriented separation and purification were performed by high-speed countercurrent chromatography combined with semi-preparative high-performance liquid chromatography and the purity of the four compounds isolated was higher than 90%. It will help to provide more opportunities to discover and develop new potential therapeutic remedies from health care food resources.


Asunto(s)
Gota , Poria , Poria/química , Xantina Oxidasa , Simulación del Acoplamiento Molecular , Cromatografía Líquida de Alta Presión/métodos , Inhibidores Enzimáticos/farmacología , Distribución en Contracorriente , Gota/tratamiento farmacológico
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