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Organic polyradicals with a high-spin ground state and quantum magnetic properties suitable for spin manipulation are valuable materials for diverse innovative technologies, including quantum devices. However, the typically high reactivity and low stability of conventional polyradicals present a major obstacle to such applications. In this study, a highly stable carbon-centered triradical TR with a quartet ground state and excellent stability (τ1/2 of â¼90 days in air-saturated toluene at room temperature) is achieved, which shows apposite magnetic anisotropy and Zeeman splitting partition with favorable addressability. By virtue of the optimal stability, thorough structural and magnetic characterizations are realized. With X-ray crystallography unambiguously proving the molecular structure, the quartet ground state (ΔED-Q = 0.78 kcal/mol) is confirmed by the SQUID measurements, while the cw- and pulsed EPR techniques offer additional supportive evidence for the high-spin nature. Remarkably, owing to the easily attained magnetic anisotropy, selective excitations between different Zeeman splitting levels are successfully demonstrated with TR in its frozen toluene solution without the requirement for special alignment, which is unprecedented for organic polyradicals. Along with the millisecond spin-lattice relaxation and microsecond coherence time manifested by TR, this triradical is promising for potential coherent spin manipulation applications as a multienergy-level quantum information carrier.
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BACKGROUND: DNA methylation is an important epigenetic mode of genomic DNA modification and plays a vital role in maintaining epigenetic content and regulating gene expression. Cytosine-5 DNA methyltransferase (C5-MTase) are the key enzymes in the process of DNA methylation. However, there is no systematic analysis of the C5-MTase in cotton so far, and the function of DNMT2 genes has not been studied. METHODS: In this study, the whole genome of cotton C5-MTase coding genes was identified and analyzed using a bioinformatics method based on information from the cotton genome, and the function of GhDMT6 was further validated by VIGS experiments and subcellular localization analysis. RESULTS: 33 C5-MTases were identified from three cotton genomes, and were divided into four subfamilies by systematic evolutionary analysis. After the protein domain alignment of C5-MTases in cotton, 6 highly conserved motifs were found in the C-terminus of 33 proteins involved in methylation modification, which indicated that C5-MTases had a basic catalytic methylation function. These proteins were divided into four classes based on the N-terminal difference, of which DNMT2 lacks the N-terminal regulatory domain. The expression of C5-MTases in different parts of cotton was different under different stress treatments, which indicated the functional diversity of cotton C5-MTase gene family. Among the C5-MTases, the GhDMT6 had a obvious up-regulated expression. After silencing GhDMT6 with VIGS, the phenotype of cotton seedlings under different stress treatments showed a significant difference. Compared with cotton seedlings that did not silence GhDMT6, cotton seedlings silencing GhDMT6 showed significant stress resistance. CONCLUSION: The results show that C5-MTases plays an important role in cotton stress response, which is beneficial to further explore the function of DNMT2 subfamily genes.
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Sequías , Gossypium , Gossypium/genética , Gossypium/enzimología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Metilación de ADN , Regulación de la Expresión Génica de las Plantas , Tolerancia a la Sal/genética , Familia de Multigenes , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Filogenia , Genoma de Planta , Genes de PlantasRESUMEN
P-coumaric acid (p-CA), a pant metabolite with antioxidant and anti-inflammatory activity, is extensively utilized in biomedicine, food, and cosmetics industry. In this study, a synthetic pathway (PAL) for p-CA was designed, integrating three enzymes (AtPAL2, AtC4H, AtATR2) into a higher l-phenylalanine-producing strain Escherichia coli PHE05. However, the lower soluble expression and activity of AtC4H in the PAL pathway was a bottleneck for increasing p-CA titers. To overcome this limitation, the soluble expression of AtC4H was enhanced through N-terminal modifications. And an optimal mutant, AtC4HL373T/G211H, which exhibited a 4.3-fold higher kcat/Km value compared to the wild type, was developed. In addition, metabolic engineering strategies were employed to increase the intracellular NADPH pool. Overexpression of ppnk in engineered E. coli PHCA20 led to a 13.9-folds, 1.3-folds, and 29.1% in NADPH content, the NADPH/NADP+ ratio and p-CA titer, respectively. These optimizations significantly enhance p-CA production, in a 5-L fermenter using fed-batch fermentation, the p-CA titer, yield and productivity of engineered strain E. coli PHCA20 were 3.09 g/L, 20.01 mg/g glucose, and 49.05 mg/L/h, respectively. The results presented here provide a novel way to efficiently produce the plant metabolites using an industrial strain.
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Ácidos Cumáricos , Escherichia coli , Glucosa , Ingeniería Metabólica , Propionatos , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Cumáricos/metabolismo , Ingeniería Metabólica/métodos , Glucosa/metabolismo , Propionatos/metabolismoRESUMEN
The Rh(III)-catalyzed annulation of benzoic acids with nitroalkenes was disclosed to afford a wide range of 3,4-disubstituted isochroman-1-ones with excellent regioselectivity and high catalytic efficiency. Both aromatic and aliphatic nitroalkenes participated in this cyclization reaction successfully. The synthetic value of 3,4-disubstituted isochroman-1-ones was proven by a series of derivatizations. Furthermore, a reliable mechanism is outlined on the basis of experimental investigations and related precedents.
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In this paper, the hydrogenation of aldehydes and ketones using the RANEY® nickel catalyst was successfully applied for the synthesis of alcohol compounds without additional column chromatographic purification. This synthetic strategy features a wide range of substrates, excellent atom economy, high chemical discrimination and the use of a ligand-free catalytic system. Reactions were performed at room temperature in water providing alcohols in high yields and purity.
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BACKGROUND: Many proteins of African swine fever virus (ASFV, such as p72, p54, p30, CD2v, K205R) have been successfully expressed and characterized. However, there are few reports on the DP96R protein of ASFV, which is the virulence protein of ASFV and plays an important role in the process of host infection and invasion of ASFV. RESULTS: Firstly, the prokaryotic expression vector of DP96R gene was constructed, the prokaryotic system was used to induce the expression of DP96R protein, and monoclonal antibody was prepared by immunizing mice. Four monoclonal cells of DP96R protein were obtained by three ELISA screening and two sub-cloning; the titer of ascites antibody was up to 1:500,000, and the monoclonal antibody could specifically recognize DP96R protein. Finally, the subtypes of the four strains of monoclonal antibodies were identified and the minimum epitopes recognized by them were determined. CONCLUSION: Monoclonal antibody against ASFV DP96R protein was successfully prepared and identified, which lays a foundation for further exploration of the structure and function of DP96R protein and ASFV diagnostic technology.
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Virus de la Fiebre Porcina Africana , Anticuerpos Monoclonales , Epítopos , Ratones Endogámicos BALB C , Proteínas Virales , Animales , Femenino , Ratones , Fiebre Porcina Africana/inmunología , Fiebre Porcina Africana/virología , Virus de la Fiebre Porcina Africana/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Epítopos/inmunología , Porcinos , Proteínas Virales/inmunologíaRESUMEN
OBJECTIVES: The objective of this study was to examine the association between dietary diversity and sleep quality among Chinese middle-aged and older adults. METHODS: The Lifestyle and Healthy Aging of Chinese Square Dancer Study is a prospective, community-based cohort study that enrolled participants aged 45 years and above from 2020 to 2021. Using the semiquantitative food frequency questionnaire to investigate the diets of study participants, and using the Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality. Dietary diversity was assessed using two scoring methods covering ten food groups and 66 food items, respectively: the dietary diversity score (DDS) and the food variety score (FVS). The higher scores of DDS and FVS indicated greater dietary diversity and higher dietary quality. Logistic regression analysis explored the associations between these scores and sleep quality. RESULTS: A total of 2409 individuals with completed information on PSQI and FFQ were included in this study, of whom 767 (31.8%) had poor sleep quality. Participants with higher DDS were associated with an 18% lower odds of poor sleep quality compared to those with low DDS (OR = 0.82, 95% CI, 0.68-0.98). Participants in the highest quartile of the FVS had a 32% lower odds of poor sleep quality than those in the lowest quartile (OR = 0.68, 95% CI, 0.52-0.89). CONCLUSIONS: There was a positive correlation between higher FVS and DDS with better sleep quality. Therefore, ensuring a diverse diet may be beneficial for maintaining good sleep quality among middle-aged and older adults.
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Dieta , Calidad del Sueño , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , China , Estudios Prospectivos , Dieta/estadística & datos numéricos , Estudios de Cohortes , Encuestas y Cuestionarios , Pueblos del Este de AsiaRESUMEN
Pressure-induced topochemical polymerization of molecular crystals with various stackings is a promising way to synthesize materials with different co-existing sub-structures. Here, by compressing the azobenzene crystal containing two kinds of intermolecular stacking, we synthesized an ordered van der Waals carbon nanoribbon (CNR) heterostructure in one step. Azobenzene polymerizes via a [4 + 2] hetero-Diels-Alder (HDA) reaction of phenylazo-phenyl in layer A and a para-polymerization reaction of phenyl in layer B at 18 GPa, as evidenced by in situ Raman and IR spectroscopies, X-ray diffraction, as well as gas chromatography-mass spectrometry and the solid-state nuclear magnetic resonance of the recovered products. The theoretical calculation shows that the obtained CNR heterostructure has a type II (staggered) band gap alignment. Our work highlights a high-pressure strategy to synthesize bulk CNR heterostructures.
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Deciphering the three-dimensional (3D) insight into nanocatalyst surfaces at the atomic level is crucial to understanding catalytic reaction mechanisms and developing high-performance catalysts. Nevertheless, better understanding the inherent insufficiency of a long-range ordered lattice in nanocatalysts is a big challenge. In this work, we report the local structure of Pd nanocatalysts, which is beneficial for demonstrating the shape-structure-adsorption relationship in acetylene hydrogenation. The 5.27 nm spherical Pd catalyst (Pdsph) shows an ethylene selectivity of 88% at complete acetylene conversion, which is much higher than those of the Pd octahedron and Pd cube and superior to other reported monometallic Pd nanocatalysts so far. By virtue of the local structure revelation combined with the atomic pair distribution function (PDF) and reverse Monte Carlo (RMC) simulation, the atomic surface distribution of the unique compressed strain of Pd-Pd pairs in Pdsph was revealed. Density functional theory calculations verified the obvious weakening of the ethylene adsorption energy on account of the surface strain of Pdsph. It is the main factor to avoid the over-hydrogenation of acetylene. The present work, entailing shape-induced surface strain manipulation and atomic 3D insight, opens a new path to understand and optimize chemical activity and selectivity in the heterogeneous catalysis process.
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BACKGROUND: Previous studies have revealed that sodium-restricted diet intervention significantly decreased apnea frequency among patients with sleep apnea. However, the longitudinal association between the habit of adding salt to foods and sleep apnea in general populations is uncertain. METHODS: The UK Biobank cohort study includes more than 500,000 participants aged 40 to 69 across the United Kingdom from 2006 to 2010. The frequency of adding salt to foods was collected through a touch screen questionnaire. Incident sleep apnea was ascertained by hospital inpatient records, death registries, primary care, and self-reported diagnosis. The association between the habit of adding salt to foods and incident sleep apnea was estimated using Cox proportional hazard regression models. RESULTS: Among the 488,196 participants (mean age 56.5 years; 55.0% female) in this study. During a median follow-up of 12.3 years, 6394 sleep apnea events occurred. Compared to participants who never/rarely added salt to foods, those who sometimes, usually, and always added salt to foods had an 11% (hazard ratio [HR] 1.11, 95% confidence interval [CI]: 1.04 to 1.17), 15% (HR 1.15, 95% CI: 1.07 to 1.24), and 24% (HR 1.24, 95% CI: 1.12 to 1.37) higher risk for incident sleep apnea, respectively. CONCLUSIONS: In this large prospective study, the habit of adding salt to foods was associated with a higher risk of incident sleep apnea. The findings support the benefits of a salt reduction program in preventing sleep apnea.
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Síndromes de la Apnea del Sueño , Humanos , Femenino , Persona de Mediana Edad , Masculino , Estudios Prospectivos , Estudios de Cohortes , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/epidemiología , Modelos de Riesgos Proporcionales , Conducta Alimentaria , Factores de RiesgoRESUMEN
A Dioscorea opposita Thunb polysaccharide (DOP)-modified ZIF8 material was developed in this study, which can be used as a "smart" glucose-responsive carrier to control the slow release of drugs. The 3-aminophenylboronic acid (APBA) functionalized carboxylated long-chain polymer poly(ethylene glycol) (PEG) segments, which were first modified on the surface of ZIF8 nanoparticles with a hydrogen bond and then chemically cross-linked with DOP through a borate ester bond, leading to the drugs loaded on ZIF8 being "closed" in PBS but being "open" via taking off the DOP coating in high concentrations of glucose; thus, leakage can be prevented in the drug loaded and a glucose-triggered release can effectively result. Moreover, the materials showed good biocompatibility and the released trans-N-p-coumaroyltyramine (NCT) could work synergistically with the DOP to improve insulin resistance and promote glucose consumption in insulin-resistant HepG2 cells.
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Dioscorea , Glucosa , Dioscorea/química , Polisacáridos/química , InsulinaRESUMEN
Plants are sessile organisms suffering severe environmental conditions. Drought stress is one of the major environmental issues that affect plant growth and productivity. Although complex regulatory gene networks of plants under drought stress have been analyzed extensively, the response mechanism in the early stage of drought stress is still rarely mentioned. Here, we performed transcriptome analyses on cotton samples treated for a short time (10 min, 30 min, 60 min, 180 min) using 10% PEG, which is used to simulate drought stress. The analysis of differently expressed genes (DEGs) showed that the number of DEGs in roots was obviously more than that in stems and leaves at the four time points and maintained >2000 FDEGs (DEGs appearing for the first time) from 10 min, indicating that root tissues of plants respond to drought stress quickly and continuously strongly. Gene ontology (GO) analysis showed that DEGs in roots were mainly enriched in protein modification and microtubule-based process. DEGs were found significantly enriched in phosphatidylinositol signaling system at 10 min through Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, implying the great importance of phosphatidylinositol signal in the early stage of drought stress. What was more, two co-expression modules, which were significantly positively correlated with drought stress, were found by Weighted Gene Co-expression Network Analysis (WGCNA). From one of the co-expression modules, we identified a hub-gene Gohir.A07G058200, which is annotated as "phosphatidylinositol 3- and 4-kinase" in phosphatidylinositol signaling system, and found this gene may interact with auxin-responsive protein. This result suggested that Gohir.A07G058200 may be involved in the crosstalk of phosphatidylinositol signal and auxin signal in the early stage of drought stress. In summary, through transcriptome sequencing, we found that phosphatidylinositol signaling system is an important signal transduction pathway in early stage in response to drought stress, and it may interact with auxin signal transduction through phosphatidylinositol 3- and 4-kinase.
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Sequías , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión Génica , Ácidos Indolacéticos , Fosfatidilinositoles , Transducción de Señal , Estrés Fisiológico/genética , TranscriptomaRESUMEN
This study aimed to investigate the effect of treadmill exercise on neuropathic pain and to determine whether mitophagy of the anterior cingulate cortex (ACC) contributes to exercise-mediated amelioration of neuropathic pain. Chronic constriction injury of the sciatic nerve (CCI) was used to establish a neuropathic pain model in Sprague-Dawley (SD) rats. Von-Frey filaments were used to assess the mechanical paw withdrawal threshold (PWT), and a thermal radiation meter was used to assess the thermal paw withdrawal latency (PWL) in rats. qPCR was used to evaluate the mRNA levels of Pink1, Parkin, Fundc1, and Bnip3. Western blot was used to evaluate the protein levels of PINK1 and PARKIN. To determine the impact of the mitophagy inducer carbonyl cyanide m-chlorophenylhydrazone (CCCP) on pain behaviors in CCI rats, 24 SD rats were randomly divided into CCI drug control group (CCI+Veh group), CCI+CCCP low-dose group (CCI+CCCP0.25), CCI+CCCP medium-dose group (CCI+CCCP2.5), and CCI+CCCP high-dose group (CCI+CCCP5). Pain behaviors were assessed on 0, 1, 3, 5, and 7 days after modeling. To explore whether exercise regulates pain through mitophagy, 24 SD rats were divided into sham, CCI, and CCI+Exercise (CCI+Exe) groups. The rats in the CCI+Exe group underwent 4-week low-moderate treadmill training one week after modeling. The mechanical pain and thermal pain behaviors of the rats in each group were assessed on 0, 7, 14, 21, and 35 days after modeling. Western blot was used to detect the levels of the mitophagy-related proteins PINK1, PARKIN, LC3 II/LC3 I, and P62 in ACC tissues. Transmission electron microscopy was used to observe the ultrastructure of mitochondrial morphology in the ACC. The results showed that: (1) Compared with the sham group, the pain thresholds of the ipsilateral side of the CCI group decreased significantly (P < 0.001). Meanwhile, the mRNA and protein levels of Pink1 were significantly higher, and those of Parkin were lower in the CCI group (P < 0.05). (2) Compared with the CCI+Veh group, each CCCP-dose group showed higher mechanical and thermal pain thresholds, and the levels of PINK1 and LC3 II/LC3 I were elevated significantly (P < 0.05, P < 0.01). (3) The pain thresholds of the CCI+Exe group increased significantly compared with those of the CCI group after treadmill intervention (P < 0.001, P < 0.01). Compared with the CCI group, the protein levels of PINK1 and P62 were decreased (P < 0.001, P < 0.01), and the protein levels of PARKIN and LC3 II/LC3 I were increased in the CCI+Exe group (P < 0.01, P < 0.05). Rod-shaped mitochondria were observed in the ACC of CCI+Exe group, and there were little mitochondrial fragmentation, swelling, or vacuoles. The results suggest that the mitochondrial PINK1/PARKIN autophagy pathway is blocked in the ACC of neuropathic pain model rats. Treadmill exercise could restore mitochondrial homeostasis and relieve neuropathic pain via the PINK1/PARKIN pathway.
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Mitofagia , Neuralgia , Ratas , Animales , Mitofagia/fisiología , Ratas Sprague-Dawley , Carbonil Cianuro m-Clorofenil Hidrazona/farmacología , Giro del Cíngulo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Quinasas , Proteínas de la Membrana/metabolismo , Proteínas Mitocondriales/metabolismoRESUMEN
Stable carbon-based polyradicals exhibiting strong spin-spin coupling and slow depolarization processes are particularly attractive functional materials. A new molecular motif synthesized by a convenient method that allows the integration of stable, high-spin radicals to (hetero)aromatic polycycles has been developed, as illustrated by a non-Kekulé diradical showing a triplet ground state with long persistency (τ1/2 ≈31â h) in air. Compared to the widely used 1,3-phenylene, the newly designed (diaza)pyrene-4,10-diyl moiety is for the first time demonstrated to confer ferromagnetic (FM) spin coupling, allowing delocalized non-disjoint SOMOs. With the X-ray crystallography unambiguously proving the diradical structure, the triplet ground state was thoroughly characterized. A large ΔES-T of 1.1â kcal/mol, proving the strong FM coupling effect, was revealed consistently by superconducting quantum interference device (SQUID) measurements and variable-temperature electron paramagnetic resonance (EPR) spectroscopy, while the zero-field splitting and triplet nutation characters were examined by continuous-wave and pulsed EPR spectroscopy. A millisecond spin-lattice relaxation time was also detected. The current study not only offers a new molecular motif enabling FM coupling between carbon-based spins, but more importantly presents a general method for installing stable polyradicals into functional π-systems.
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Developing cost-effective and sustainable acidic water oxidation catalysts requires significant advances in material design and in-depth mechanism understanding for proton exchange membrane water electrolysis. Herein, we developed a single atom regulatory strategy to construct Co-Co dinuclear active sites (DASs) catalysts that atomically dispersed zirconium doped Co9 S8 /Co3 O4 heterostructure. The X-ray absorption fine structure elucidated the incorporation of Zr greatly facilitated the generation of Co-Co DASs layer with stretching of cobalt oxygen bond and S-Co-O heterogeneous grain boundaries interfaces, engineering attractive activity of significantly reduced overpotential of 75â mV at 10â mA cm-2 , a breakthrough of 500â mA cm-2 high current density, and water splitting stability of 500â hours in acid, making it one of the best-performing acid-stable OER non-noble metal materials. The optimized catalyst with interatomic Co-Co distance (ca. 2.80â Å) followed oxo-oxo coupling mechanism that involved obvious oxygen bridges on dinuclear Co sites (1,090â cm-1 ), confirmed by in situ SR-FTIR, XAFS and theoretical simulations. Furthermore, a major breakthrough of 120,000â mA g-1 high mass current density using the first reported noble metal-free cobalt anode catalyst of Co-Co DASs/ZCC in PEM-WE at 2.14â V was recorded.
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Transition-metal-catalyzed directed C-H alkenylation with maleimides has attracted much attention in recent years, as maleimide core moieties are present in various natural products and pharmaceuticals. In addition, these derivatives can be readily modified into biologically important compounds including succinimides, pyrrolidines and γ-lactams. The efficient chelation-assisted inert C-H bond activation strategy provides straightforward access to a wide array of structurally diverse molecules containing maleimide units. This review describes the major progress and mechanistic investigations on Heck-type reaction/cyclization of maleimides with organic molecules until early 2022.
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Elementos de Transición , Catálisis , Ciclización , Maleimidas/química , Estructura Molecular , Elementos de Transición/químicaRESUMEN
A novel hydrogel (DOP/PEI-PBA) based on the "three-component" reaction of 2-formylphenylboric acid (2-FPBA), the primary amine group of polyethyleneimine (PEI) and the cis-o-dihydroxy groups of Dioscorea opposita Thunb polysaccharide (DOP) was designed in this work. The hydrogel can be easily prepared by simply mixing the three reactants at room temperature. The hydrogel had dual responsiveness to glucose and pH, and can realize the controllable release of insulin. Moreover, the hydrogel combining insulin and DOP can inhibit the reactive oxygen species (ROS) level and malondialdehyde (MDA) content, and promote glucose consumption as well as the level of superoxide dismutase (SOD), in high-glucose-induced injury in HL-7702 cells, which reflects the synergistic effect of insulin and DOP to protect hepatocytes from oxidative stress at the same time. Further in vitro cytotoxicity studies showed that the hydrogel had good biocompatibility and no obvious toxicity to cells. These indicate that the prepared hydrogel (DOP/PEI-PBA) can be expected to be applied in the clinical treatment of insulin deficiency in diabetes.
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Dioscorea , Preparaciones de Acción Retardada , Carbohidratos de la Dieta , Glucosa , Hidrogeles/farmacología , Insulina , Insulina Regular Humana , Polisacáridos/química , Polisacáridos/farmacologíaRESUMEN
BACKGROUND: The Raffinose synthetase (RAFS) genes superfamily is critical for the synthesis of raffinose, which accumulates in plant leaves under abiotic stress. However, it remains unclear whether RAFS contributes to resistance to abiotic stress in plants, specifically in the Gossypium species. RESULTS: In this study, we identified 74 RAFS genes from G. hirsutum, G. barbadense, G. arboreum and G. raimondii by using a series of bioinformatic methods. Phylogenetic analysis showed that the RAFS gene family in the four Gossypium species could be divided into four major clades; the relatively uniform distribution of the gene number in each species ranged from 12 to 25 based on species ploidy, most likely resulting from an ancient whole-genome polyploidization. Gene motif analysis showed that the RAFS gene structure was relatively conservative. Promoter analysis for cis-regulatory elements showed that some RAFS genes might be regulated by gibberellins and abscisic acid, which might influence their expression levels. Moreover, we further examined the functions of RAFS under cold, heat, salt and drought stress conditions, based on the expression profile and co-expression network of RAFS genes in Gossypium species. Transcriptome analysis suggested that RAFS genes in clade III are highly expressed in organs such as seed, root, cotyledon, ovule and fiber, and under abiotic stress in particular, indicating the involvement of genes belonging to clade III in resistance to abiotic stress. Gene co-expressed network analysis showed that GhRFS2A-GhRFS6A, GhRFS6D, GhRFS7D and GhRFS8A-GhRFS11A were key genes, with high expression levels under salt, drought, cold and heat stress. CONCLUSION: The findings may provide insights into the evolutionary relationships and expression patterns of RAFS genes in Gossypium species and a theoretical basis for the identification of stress resistance materials in cotton.
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Regulación de la Expresión Génica de las Plantas , Gossypium , Perfilación de la Expresión Génica , Genoma de Planta , Gossypium/genética , Ligasas , Familia de Multigenes , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rafinosa , Estrés Fisiológico/genéticaRESUMEN
To investigate the capability of π-π stacking motifs to enable spin-spin coupling, we designed and synthesized three pairs of regio-isomers featuring two radical moieties joined by a [2.2]paracyclophane (CP) unit. By fusing indeno units to CP, two partially stacked fluorene radicals are covalently linked, exhibiting evident antiferromagnetic (AFM) coupling regardless of the orientation of two spins. Remarkably, while possessing high diradical indices of 0.8 and 0.9, the two molecules demonstrate good air stability by virtue of their singlet ground state. Single crystals help unravel the structural basis of their AFM coupling behaviors. When two radical centers are arranged at the pseudometa-positions around CP, the face-to-face stacked phenylene rings intrinsically confer orbital interactions that promote AFM coupling. On the other hand, if two radicals are directed in the pseudopara-orientation, significant orbital overlapping is observed between the radical centers (i.e., C9 of fluorene) and the aromatic carbons laid on the side, rendering AFM coupling between the two spins. In contrast, when two fluorene radicals are tethered to CP via C9 through a single C-C bond, ferromagnetic (FM) coupling is manifested by both diradical isomers featuring pseudometa- and pseudopara-connectivity. With minimal spin distributed on CP and thus limited contribution from π-π stacking, their spin-spin coupling properties are more similar to a pair of nitroxide diradical analogues, in which the two spins are dominantly coupled via through-space interactions. From these results, important conclusions are elucidated such as that although through-space interactions may confer FM coupling, with weakened strength shown by PAH radicals due to their lower polarity, face-to-face stacked π-frameworks tend to induce AFM coupling, because favorable orbital interactions are readily achieved by PAH systems hosting delocalized spins that are capable of adopting varied stacking motifs.
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Depression is a commonly occurring neuropsychiatric disease with an increasing incidence rate. Saikosaponin A (SA), a major bioactive component extracted from Radix Bupleuri, possesses anti-malignant cell proliferation, anti-inflammation, anti-oxidation and liver protective effects. However, few studies have investigated SA's antidepressant effects and pharmacological mechanisms of action. Our study aimed to explore the anti-depression effect of SA and screen the target proteins regulated by SA in a rat model of chronic unpredictable mild stress (CUMS)-induced depression. Results showed that 8-week CUMS combined with separation could successfully produce depressive-like behaviours and cause a decrease of dopamine (DA) in rat hippocampus, and 4-week administration of SA could relieve CUMS rats' depressive symptoms and up-regulated DA content. There were 15 kinds of significant differentially expressed proteins that were detected not only between the control and CUMS groups, but also between the CUMS and SA treatment groups. Proline-rich transmembrane protein 2 (PRRT2) was down-regulated by CUMS while up-regulated by SA. These findings reveal that SA may exert antidepressant effects by up-regulating the expression level of PRRT2 and increasing DA content in hippocampus. The identification of these 15 differentially expressed proteins, including PRRT2, provides further insight into the treatment mechanism of SA for depression.