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Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces. Using scanning tunneling microscopy, we examine the reaction process at the single-molecular level, quantify the selectivity of the dehydrobrominative cross-coupling, and reveal the modulation of selectivity by substrate lattice-related catalytic activity or molecular assembly effect. Theoretical calculations indicate that the dehydrobrominative cross-coupling proceeds via regioselective C-H bond activation of debrominated TBPB and subsequent highly selective C-C coupling of the radical-based intermediates. The reaction kinetics plays an important role in the selectivity for the cross-coupling. This work not only expands the toolbox for chemical synthesis but also provides important mechanistic insights into the selectivity of coupling reactions on the surface.
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PURPOSE: This article provided a comprehensive scoping review, synthesizing existing literature on the financial distress faced by breast cancer patients. It examined the factors contributing to financial distress, the impact on patients, coping mechanisms employed, and potential alleviation methods. The goal was to organize existing evidence and highlight possible directions for future research. METHODS: We followed the scoping review framework proposed by the Joanna Briggs Institute (JBI) to synthesize and report evidence. We searched electronic databases, including PubMed, Web of Science, Embase, and Cochrane Library, for relevant literature. We included English articles that met the following criteria: (a) the research topic was financial distress or financial toxicity, (b) the research subjects were adult breast cancer patients, and (c) the article type was quantitative, qualitative, or mixed-methods research. We then extracted and integrated relevant information for reporting. RESULTS: After removing duplicates, 5459 articles were retrieved, and 43 articles were included based on the inclusion and exclusion criteria. The articles addressed four main themes related to financial distress: factors associated with financial distress, impact on breast cancer patients, coping mechanisms, and potential methods for alleviation. The impact of financial distress on patients was observed in six dimensions: financial expenses, financial resources, social-psychological reactions, support seeking, coping care, and coping lifestyle. While some studies reported potential methods for alleviation, few discussed the feasibility of these solutions. CONCLUSIONS: Breast cancer patients experience significant financial distress with multidimensional impacts. Comprehensive consideration of possible confounding factors is essential when measuring financial distress. Future research should focus on exploring and validating methods to alleviate or resolve this issue.
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Adaptación Psicológica , Neoplasias de la Mama , Estrés Financiero , Humanos , Neoplasias de la Mama/psicología , Neoplasias de la Mama/economía , Estrés Financiero/psicología , Femenino , Costo de EnfermedadRESUMEN
This paper investigated the effect of total saponins from Rhizoma Panacis Majoris on the proliferation, apoptosis, and autophagy of human cervical carcinoma HeLa cells. The saponin content was detected by ultraviolet-visible spectrophotometry. Cell coun-ting kit-8(CCK-8) assay, 4,6-diamidino-2-phenylindole(DAPI) staining, and flow cytometry were used to detect the effects of total saponins of Panacis Majoris Rhizoma on cell viability, morphology, cell cycle and apoptosis of HeLa cells. Western blot was used to detect the expression of apoptosis-related proteins B cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax), cleaved caspase-9, and cleaved caspase-3, autophagy-related proteins Beclin-1 and SQSTM1(p62), and the proteins related to the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/Akt/mTOR) and mitogen-activated protein kinase(MAPK) signaling pathways. It was found that the yield and saponin content of total saponins from Rhizoma Panacis Majoris were 6.3% and 78.3%, respectively. Total saponins from Rhizoma Panacis Majoris could significantly inhibit the proliferation(P<0.001), effect the nuclear morphology, block the G_0/G_1 cycle, and induce cell apoptosis in HeLa cells with a concentration-dependent manner. In addition, total saponins from Rhizoma Panacis Majoris up-regulated the expression of pro-apoptotic proteins Bax, cleaved caspase-9, and cleaved caspase-3, and autophagy-related protein p62(P<0.05), while down-regulated the expression of anti-apoptotic protein Bcl-2 and autophagy-related protein Beclin-1(P<0.01). Total saponins from Rhizoma Panacis Majoris could promote the expression of p-p38/p38, p-Jun N-terminal kinase(JNK)/JNK, p-PI3K/PI3K, p-Akt/Akt, p-mTOR/mTOR proteins in PI3K/Akt/mTOR and MAPK signaling pathways(P<0.05). In contrast, the effect on p-ERK/ERK expression was not obvious. Therefore, total saponins from Rhizoma Panacis Majoris may inhibit autophagy and promote apoptosis of HeLa cells through the activation of the PI3K/Akt/mTOR, c-JNK, and p38 MAPK signaling pathways, which indicates that total saponins from Rhizoma Panacis Majoris may have a potential role in cervical cancer treatment.
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Apoptosis , Autofagia , Proliferación Celular , Rizoma , Saponinas , Neoplasias del Cuello Uterino , Humanos , Saponinas/farmacología , Saponinas/química , Células HeLa , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Autofagia/efectos de los fármacos , Rizoma/química , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología , Femenino , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/genética , Supervivencia Celular/efectos de los fármacosRESUMEN
Panax ginseng, an essential component of traditional medicine and often referred to as the king of herbs, has played a pivotal role in medicine globally for several millennia. Previously, traditional phytochemical methods were mainly used for quality evaluation and pharmacological mechanism studies of ginseng, resulting in the lack of systematicness and innovation and hindering the development and utilization of ginseng resources. Since the beginning of the new century, systems biology technology represented by metabolomics has shown unique advantages in the modernization and internationalization of herbal medicine, establishing a bridge for communication between traditional medicine and modern medicine. P. ginseng, a special herb used in medicine and food, is one of the main research objects for qualitative and quantitative analysis of metabolomics and has gradually become the focus of researchers globally. Here, we conducted a comprehensive summary and analysis of numerous studies published in ginseng metabolomics. This review aims to provide more novel ideas for the quality evaluation, development, and clinical application of ginseng in the future and offer more useful technical references for the modernization and internationalization of herbal medicine based on metabolomics.
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Panax , Plantas Medicinales , Metabolómica/métodos , Extractos Vegetales/análisisRESUMEN
We report herein the in situ electrochemical scanning tunneling microscopy (ECSTM) study on the synergistic effect of Mg2+ in CO2 reduction reaction (CO2RR) catalyzed by cobalt phthalocyanine (CoPc). ECSTM measurement molecularly resolves the self-assembled CoPc monolayer on the Au(111) substrate. In the CO2 environment, high-contrast species are observed in the adlayer and assigned to the CO2 adsorption on CoPc. Furthermore, the contrast of the CO2-bound complex is higher in Mg2+-containing electrolytes than in Mg2+-free electrolytes, indicating the formation of the CoPc-CO2-Mg2+ complex. The surface coverage of adsorbed CO2 is positively correlated with the Mg2+ concentration as the additive in electrolytes up to a plateau of 30.8 ± 2.7% when c(Mg2+) > 30 mM. The potential step experiment indicates the higher CO2 adsorption dynamics in Mg2+-containing electrolytes than without Mg2+. The rate constants of CO2 adsorption and dissociation in different electrolytes are extracted from the data fitting of statistical results from in situ ECSTM experiments.
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Microscopía de Túnel de Rastreo , Compuestos Organometálicos , Microscopía de Túnel de Rastreo/métodos , Dióxido de Carbono , OroRESUMEN
Ischemic stroke remains one of the leading causes of death worldwide, thereby highlighting the urgent necessary to identify new therapeutic targets. Deoxyhypusine hydroxylase (DOHH) is a fundamental enzyme catalyzing a unique posttranslational hypusination modification of eukaryotic translation initiation factor 5A (eIF5A) and is highly involved in the progression of several human diseases, including HIV-1 infection, cancer, malaria, and diabetes. However, the potential therapeutic role of pharmacological regulation of DOHH in ischemic stroke is still poorly understood. Our study first discovered a natural small-molecule brazilin (BZ) with an obvious neuroprotective effect against oxygen-glucose deprivation/reperfusion insult. Then, DOHH was identified as a crucial cellular target of BZ using HuProt™ human proteome microarray. By selectively binding to the Cys232 residue, BZ induced a previously undisclosed allosteric effect to significantly increase DOHH catalytic activity. Furthermore, BZ-mediated DOHH activation amplified mitophagy for mitochondrial function and morphology maintenance via DOHH/eIF5A hypusination signaling pathway, thereby protecting against ischemic neuronal injury in vitro and in vivo. Collectively, our study first identified DOHH as a previously unreported therapeutic target for ischemic stroke, and provided a future drug design direction for DOHH allosteric activators using BZ as a novel molecular template.
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Benzopiranos/uso terapéutico , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Oxigenasas de Función Mixta/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Animales , Benzopiranos/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Células Cultivadas , Femenino , Humanos , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/patología , Masculino , Ratones Endogámicos ICR , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fármacos Neuroprotectores/farmacología , Embarazo , Procesamiento Proteico-Postraduccional , Ratas Wistar , Pez CebraRESUMEN
Trimethyltin chloride (TMT) is an organotin heat stabilizer that is widely used in the production of plastics, and has strong toxicity. Here, the effect of trimethyltin chloride on mouse kidneys and its related mechanism were studied by taking TMT mouse with drinking water as a model. Histological examination and TUNEL results showed that the trimethyltin chloride group had typical apoptosis and necroptosis characteristics. Therefore, the level of oxidative stress was detected,and the expression of related genes was verified by real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot methods. The results showed that oxidative stress was activated (MDA,SOD,CAT,T-AOC), released ROS, activated NF-κB pathway,activated inflammasome (NLRP3,Caspase-1,ASC), and inflammasome-secreted inflammatory factors (IL-1ß). The expression of apoptosis (BCL-2, BAX, Caspase-3, Caspase-9) and necroptosis (RIPK1, RIPK33, MLKL, Caspase-8) increased.In addition, HEK293T human embryonic kidney cells were treated with trimethyltin chloride, and the results were similar to the tissue. In conclusion, TMT can induce oxidative stress, activate NF-κB pathway, and induce apoptosis and necroptosis through inflammasomes.
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Understanding the mechanism of electrocatalytic reaction is important for the design and development of highly efficient electrocatalysts for energy technology. Investigating the surface structures of electrocatalysts and the surface processes in electrocatalytic reactions at the atomic and molecular scale is helpful to identify the catalytic role of active sites and further promotes the development of emerging electrocatalysts. Since it was invented, scanning tunnelling microscopy (STM) has become a powerful technique to investigate surface topographies and electronic properties at the nanoscale resolution. STM can be operated in diversified environments. Electrochemical STM can be used to investigate the surface processes during electrochemical reactions. Moreover, the critical intermediates in catalysis on catalyst surfaces can be identified by STM at low temperature or ultrahigh vacuum. STM has been extensively utilized in electrocatalysis research, including the structure-activity relationship of electrocatalysts, the distribution of active sites, and surface processes in electrocatalytic reactions. In this review, progress in the application of STM in electrocatalysis is systematically discussed. The construction of model electrocatalysts and electrocatalytic systems are summarized. Then, we present the STM investigation of electrocatalyst structures and surface processes related to electrocatalysis. Challenges and future developments in the field are discussed in the outlook.
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Astragali Radix is one of traditional Chinese medicines with effects in invigorating Qi for consolidating superficies, inducing diuresis to alleviate edema, promoting pus discharge and tissue regeneration. In recent years, the traditional Chinese medicine fermentation technology has received extensive attentions due to its high efficiency and safety. The pharmacological functions of traditional Chinese medicines could be further enhanced after microbial fermentation, which has a broad development prospects. In this paper, we summarized relevant literatures of Astragali Radix fermentation in such aspects as fermentation strains, fermentation forms, process optimization, active ingredients and pharmacological effects, in the expectation of providing a reference for development and utilization of Astragali Radix.
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Planta del Astrágalo , Medicamentos Herbarios Chinos , Fermentación , Medicina Tradicional China , Raíces de PlantasRESUMEN
We report a molecular investigation of a cobalt phthalocyanine (CoPc)-catalyzed CO2 reduction reaction by electrochemical scanning tunneling microscopy (ECSTM). An ordered adlayer of CoPc was prepared on Au(111). Approximately 14 % of the adsorbed species appeared with high contrast in a CO2 -purged electrolyte environment. The ECSTM experiments indicate the proportion of high-contrast species correlated with the reduction of CoII Pc (-0.2â V vs. saturated calomel electrode (SCE)). The high-contrast species is ascribed to the CoPc-CO2 complex, which is further confirmed by theoretical simulation. The sharp contrast change from CoPc-CO2 to CoPc is revealed by inâ situ ECSTM characterization of the reaction. Potential step experiments provide dynamic information for the initial stage of the reaction, which include the reduction of CoPc and the binding of CO2 , and the latter is the rate-limiting step. The rate constant of the formation and dissociation of CoPc-CO2 is estimated on the basis of the inâ situ ECSTM experiment.
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BACKGROUND: Extrahepatic metastasis is the independent risk factor of poor survival of primary hepatic carcinoma (PHC), and most occurs in the chest and abdomen. Currently, there is still no available method to predict thoracoabdominal extrahepatic metastasis in PHC. In this study, a novel nomogram model was developed and validated for prediction of thoracoabdominal extrahepatic metastasis in PHC, thereby conducted individualized risk management for pretreatment different risk population. METHODS: The nomogram model was developed in a primary study that consisted of 330 consecutive pretreatment patients with PHC. Large-scale datasets were extracted from clinical practice. The nomogram was based on the predictors optimized by data dimension reduction through Lasso regression. The prediction performance was measured by the area under the receiver operating characteristic (AUROC), and calibrated to decrease the overfit bias. Individualized risk management was conducted by weighing the net benefit of different risk population via decision curve analysis. The prediction performance was internally and independently validated, respectively. An independent-validation study using a separate set of 107 consecutive patients. RESULTS: Four predictors from 55 high-dimensional clinical datasets, including size, portal vein tumor thrombus, infection, and carbohydrate antigen 125, were incorporated to develop a nomogram model. The nomogram demonstrated valuable prediction performance with AUROC of 0.830 (0.803 in internal-validation, and 0.773 in independent-validation, respectively), and fine calibration. Individual risk probability was visually scored. Weighing the net benefit, threshold probability was classified for three-independent risk population, which was < 19.9%, 19.9-71.8% and > 71.8%, respectively. According to this classification, pretreatment risk management was based on a treatment-flowchart for individualized clinical decision-making. CONCLUSIONS: The proposed nomogram is a useful tool for pretreatment risk management of thoracoabdominal extrahepatic metastasis in PHC for the first time, and may handily facilitate timely individualized clinical decision-making for different risk population.
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Neoplasias Hepáticas/patología , Modelos Biológicos , Nomogramas , Gestión de Riesgos , Algoritmos , Calibración , Toma de Decisiones Clínicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Curva ROC , Factores de RiesgoRESUMEN
Group-V elemental monolayers were recently predicted to exhibit exotic physical properties such as nontrivial topological properties, or a quantum anomalous Hall effect, which would make them very suitable for applications in next-generation electronic devices. The free-standing group-V monolayer materials usually have a buckled honeycomb form, in contrast with the flat graphene monolayer. Here, we report epitaxial growth of atomically thin flat honeycomb monolayer of group-V element antimony on a Ag(111) substrate. Combined study of experiments and theoretical calculations verify the formation of a uniform and single-crystalline antimonene monolayer without atomic wrinkles, as a new honeycomb analogue of graphene monolayer. Directional bonding between adjacent Sb atoms and weak antimonene-substrate interaction are confirmed. The realization and investigation of flat antimonene honeycombs extends the scope of two-dimensional atomically-thick structures and provides a promising way to tune topological properties for future technological applications.
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The project was launched to analyze the effects of sulfur-fumigated Ophiopogonis Radix on endogenous metabolites in rats by metabonomics. The preparation method of sulfur-fumigated Ophiopogonis Radix in laboratory was established. Then the blood samples of SD rats in blank group,Ophiopogonis Radix extract group and sulfur-fumigated Ophiopogonis Radix extract group were investigated by UHPLC-Q-Exactive. The differential metabolites were screened and identified by PCA(principal component analysis),OPLSDA(orthogonal partial least squares discriminant analysis) and variable importance projection(VIP),and the metabolic pathways were analyzed. Finally,a total of 15 potential biomarkers were identified. Compared with the samples of Ophiopogonis Radix extract group,sulfur-fumigated Ophiopogonis Radix mainly affected the biosynthesis and metabolism of amino acids in normal rats. Its mechanism may be related to the biosynthesis of phenylalanine,tyrosine,tryptophan and aminoacyl-tRNA as well as the metabolism of phenylalanine and tryptophan. Based on UHPLC-HRMS metabonomics,this paper discussed the effects of sulfur-fumigated Ophiopogonis Radix on endogenous metabolites in rats,which provided an idea for the metabolic study of other sulfur-fumigated traditional Chinese medicines.
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Medicamentos Herbarios Chinos , Animales , Cromatografía Líquida de Alta Presión , Metabolómica , Ratas , Ratas Sprague-Dawley , AzufreRESUMEN
BACKGROUND: PBC is a prototypical autoimmune liver disease characterized by portal lymphoplasmacyte infiltration. ALD is a prototypical environment-driven disease, featured by mild lymphocyte infiltration. We hypothesize that B cells are more involved in the pathogenesis of PBC. By analysing the infiltrating B cell repertoire, we aimed to unveil greater oligoclonal expansion and active clonal exchange between liver and periphery in PBC than in ALD patients. METHODS: Using NGS of Ig H chain genes, we analysed the liver-infiltrating and paired peripheral B lymphocyte repertoire from nine PBC and four ALD patients. RESULTS: In the liver of PBC and ALD patients, (i) roughly 10% of the B lymphocytes were clonally related and highly expressed, and there were also lineages that underwent extensive clonal expansion; (ii) there was different use of IGHV/IGHJ segments between PBC and ALD, suggesting distinct Ag exposure backgrounds, but this did not lead to a significant difference in their clonal expansion level. Analysis of data sets from paired samples further revealed, (iii) direct clonal exchange and evolutionally related B cell clones between the infiltrating and peripheral repertoire; (iv) the seeding of the infiltrating clones to periphery, and peripheral ones to the liver, for further extensive evolution. CONCLUSIONS: The oligoclonally expanded nature of the infiltrating B cell repertoire implies B cell immunity is involved in the pathogenesis of both diseases. The observed clonal exchange might provide an approach to identify and monitor the infiltrating B cells through the periphery.
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Linfocitos B/inmunología , Cirrosis Hepática Biliar/inmunología , Hígado/patología , Adulto , Linfocitos B/citología , Células Clonales , Femenino , Genes de Inmunoglobulinas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by elevated serum anti-mitochondrial Ab and lymphocyte-mediated bile duct damage. This study was designed to reveal the clonal characteristics of B lymphocyte repertoire in patients with PBC to facilitate better understanding of its pathogenesis and better management of these patients. Using high-throughput sequencing of Ig genes, we analyzed the repertoire of circulating B lymphocytes in 43 patients with PBC, and 34 age- and gender-matched healthy controls. Compared with healthy controls, PBC patients showed 1) a gain of 14 new clones and a loss of 8 clones; 2) a significant clonal expansion and increased relative IgM abundance, which corresponded with the elevated serum IgM level; 3) a significant reduction of clonal diversity and somatic hypermutations in class-switched sequences, which suggested a general immunocompromised status; 4) the reduction of clonal diversity and enhancement of clonal expansion were more obvious at the cirrhotic stage; and 5) treatment with ursodeoxycholic acid could increase the clonal diversity and reduce clonal expansion of the IgM repertoire, with no obvious effect on the somatic hypermutation level. Our data suggest that PBC is a complex autoimmune disease process with evidence of B lymphocyte clonal gains and losses, Ag-dependent ogligoclonal expansion, and a generally compromised immune reserve. This new insight into the pathogenesis of PBC opens up the prospect of studying disease-relevant B cells to better diagnose and treat this devastating disease.
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Linfocitos B/patología , Colangitis/inmunología , Cirrosis Hepática Biliar/inmunología , Adulto , Anciano , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/inmunología , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Colangitis/fisiopatología , Células Clonales , Femenino , Variación Genética/efectos de los fármacos , Humanos , Inmunoglobulina M/sangre , Cirrosis Hepática Biliar/fisiopatología , Masculino , Persona de Mediana Edad , Mutación , Ácido Ursodesoxicólico/uso terapéuticoRESUMEN
Xylan is the major plant hemicellulosic polysaccharide in the secondary cell wall. The transcription factor KNOTTED-LIKE HOMEOBOX OF ARABIDOPSIS THALIANA 7 (KNAT7) regulates secondary cell wall biosynthesis, but its exact role in regulating xylan biosynthesis remains unclear. Using transactivation analyses, we demonstrate that KNAT7 activates the promoters of the xylan biosynthetic genes, IRREGULAR XYLEM 9 (IRX9), IRX10, IRREGULAR XYLEM 14-LIKE (IRX14L), and FRAGILE FIBER 8 (FRA8). The knat7 T-DNA insertion mutants have thinner vessel element walls and xylary fibers, and thicker interfascicular fiber walls in inflorescence stems, relative to wild-type (WT). KNAT7 overexpression plants exhibited opposite effects. Glycosyl linkage and sugar composition analyses revealed lower xylan levels in knat7 inflorescence stems, relative to WT; a finding supported by labeling of inflorescence walls with xylan-specific antibodies. The knat7 loss-of-function mutants had lower transcript levels of the xylan biosynthetic genes IRX9, IRX10, and FRA8, whereas KNAT7 overexpression plants had higher mRNA levels for IRX9, IRX10, IRX14L, and FRA8. Electrophoretic mobility shift assays indicated that KNAT7 binds to the IRX9 promoter. These results support the hypothesis that KNAT7 positively regulates xylan biosynthesis.
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Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Pentosiltransferasa/genética , Proteínas Represoras/metabolismo , Xilanos/biosíntesis , Vías Biosintéticas/genética , Pared Celular/metabolismo , Perfilación de la Expresión Génica , Inflorescencia/genética , Modelos Biológicos , Mutación/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas , Unión Proteica/genética , Azúcares/metabolismoRESUMEN
Ultra-high-performance liquid chromatography coupled with tandem high-resolution mass spectrometry (UHPLC-HR-MSn ) method was used to analyze the constituents of Fufang Gancao Tablets and its main metabolites in rat plasma. Rat plasma was collected both before and after oral administration of Fufang Gancao Tablets. After solid phase extraction, ACQUITY UHPLC BEH C18 (2.1 mm×100 mm, 1.7 µm) was used with 0.1% formic acid-acetonitrile solution as the mobile phase for gradient elution. The chemical components in Fufang Gancao Tablets and their prototypes and metabolites in plasma samples were analyzed by LTQ-Orbitrap equipped with an ESI ion source in a positive ion mode. Based on the accurate mass measurements, the retention time and mass fragmentation patterns, a total of 55 compounds were tentatively identified from Fufang Gancao Tablets, including 42 flavonoids, 9 triterpenes and 4 alkaloids. Furthermore, metabolites in rat plasma after oral administration of Fufang Gancao Tablets were also analyzed. A total of 26 compounds were identified, including 20 prototypes and 6 metabolites mainly through metabolic pathways of hydroxylation, glucuronide conjugation, and sulfate conjugation, etc. Our results showed that the ultra-high-performance liquid chromatography coupled with linear ion trap quadrupole Orbitrap high resolution mass spectrometry (UHPLC-LTQ-Orbitrap) could comprehensively elucidate the chemical constituents of Fufang Gancao Tablets and their migrating components in rat plasma, providing scientific basis for further studying the metabolism process and pharmacodynamic substance of Fufang Gancao Tablets.
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Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos , Animales , Flavonoides , Ratas , Comprimidos , Espectrometría de Masas en TándemRESUMEN
To identify the metabolites of Danshensu in plasma and urine in rats by using UHPLC-LTQ-Orbitrap method. After oral gavage of Danshensu CMC-Na suspension in SD rats, urine and plasma samples were collected and processed by solid phase extraction. ACQUITY UPLC BEH C18 column (2.1 mm×100 mm, 1.7 µm) was utilized, with 0.1% formic acid (A)-acetonitrile (B) solution as the mobile phase for gradient elution. Negative electrospray ion mode based data-acquisition method was established to collect the mass spectrometry data of biological samples. As a result, Danshensu and 21 Danshensu â phase and â ¡ phase metabolites were finally identified according to the accurate mass measurements, mass fragmentation behaviors and comparing with the reference standards. The main metabolic pathways included dehydration, methylation, glucuronide conjugation, sulfate conjugation and their composite reactions. Consequently, our study expounded metabolites of Danshensu in rats based on UHPLC-LTQ-Orbitrap method and provided a reference for further researches on therapeutic material basis and mechanism of Danshensu.
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Lactatos/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Lactatos/sangre , Lactatos/orina , Espectrometría de Masas , Ratas , Ratas Sprague-DawleyRESUMEN
Single-layer transition-metal dichalcogenides (TMDs) receive significant attention due to their intriguing physical properties for both fundamental research and potential applications in electronics, optoelectronics, spintronics, catalysis, and so on. Here, we demonstrate the epitaxial growth of high-quality single-crystal, monolayer platinum diselenide (PtSe2), a new member of the layered TMDs family, by a single step of direct selenization of a Pt(111) substrate. A combination of atomic-resolution experimental characterizations and first-principle theoretic calculations reveals the atomic structure of the monolayer PtSe2/Pt(111). Angle-resolved photoemission spectroscopy measurements confirm for the first time the semiconducting electronic structure of monolayer PtSe2 (in contrast to its semimetallic bulk counterpart). The photocatalytic activity of monolayer PtSe2 film is evaluated by a methylene-blue photodegradation experiment, demonstrating its practical application as a promising photocatalyst. Moreover, circular polarization calculations predict that monolayer PtSe2 has also potential applications in valleytronics.
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Procesos Fotoquímicos , Platino (Metal)/química , Compuestos de Selenio/química , SemiconductoresRESUMEN
A new and efficient Pd(II) -catalyzed intermolecular annulation of N-benzoylsulfonamide with allenes for the synthesis of 3,4-dihydroisoquinolin-1(2H)-ones is reported. This CH functionalization is compatible with ambient air and moisture, and it can be applied to terminal or internal allenes with diï¬erent synthetically attractive functional groups. Control experiments and a kinetic isotope effect study are conducted and a plausible mechanism is proposed.