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1.
Environ Res ; 262(Pt 2): 119865, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39216735

RESUMEN

With the widespread application of ternary lithium-ion batteries (TLBs) in various fields, the disposal of spent TLBs has become a globally recognized issue. This study proposes a novel method for reutilizing metal resources from TLBs. Through selective oxidation, manganese in a leaching solution of TLBs was converted into MnO2 with α, γ, and δ crystal phases (referred to as T-MnO2) for catalytic oxidation of volatile organic compounds (VOCs), while efficiently separating manganese from high-value metals such as nickel, cobalt, and lithium, achieving a manganese recovery rate of 99.99%. Compared to similar MnO2 prepared from pure materials, T-MnO2 exhibited superior degradation performance for toluene and chlorobenzene, with T90 decreasing by around 30 °C. The acidic synthesis environment provided by the leaching solution and the doping of trace metals altered the physicochemical properties of T-MnO2, such as increased specific surface area, elevated surface manganese valence, and improved redox performance and oxygen vacancy properties, enhancing its catalytic oxidation capacity. Furthermore, the degradation pathway of toluene on T-γ-MnO2 was inferred using thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) and in-situ DRIFTs. This study provides a novel approach for recycling spent TLBs and treating VOCs catalytically.

2.
Angew Chem Int Ed Engl ; : e202412680, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39166757

RESUMEN

Designing highly active and cost-effective electrocatalysts for the alkaline hydrogen oxidation reaction (HOR) is critical for advancing anion-exchange membrane fuel cells (AEMFCs). While dilute metal alloys have demonstrated substantial potential in enhancing alkaline HOR performance, there has been limited exploration in terms of rational design, controllable synthesis, and mechanism study. Herein, we developed a series of dilute Pd-Ni alloys, denoted as x% Pd-Ni, based on a trace-Pd decorated Ni-based coordination polymer through a facile low-temperature pyrolysis approach. The x% Pd-Ni alloys exhibit efficient electrocatalytic activity for HOR in alkaline media. Notably, the optimal 0.5% Pd-Ni catalyst demonstrates high intrinsic activity with an exchange current density of 0.055 mA cm-2, surpassing that of many other alkaline HOR catalysts. The mechanism study reveals that the strong synergy between Pd single atoms (SAs)/Pd dimer and Ni substrate can modulate the binding strength of proton (H)/hydroxyl (OH), thereby significantly reducing the activation energy barrier of a decisive reaction step. This work offers new insights into designing advanced dilute metal or single-atom-alloys (SAAs) for alkaline HOR and potentially other energy conversion processes.

3.
Inorg Chem ; 63(19): 8948-8957, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38687980

RESUMEN

Excellent electrocatalytic CO2 reduction reaction activity has been demonstrated by transition metals and nitrogen-codoped carbon (M-N-C) catalysts, especially for transition-metal porphyrin (MTPP)-based catalysts. In this work, we propose to use one-step low-temperature pyrolysis of the isostructural MTPP-based metal-organic frameworks (MOFs) and electrochemical in situ reduction strategies to obtain a series of hybrid catalysts of Co nanoparticles (Co NPs) and MTPP, named Co NPs/MTPP (M = Fe, Co, and Ni). The in situ introduction of Co NPs can efficiently enhance the electrocatalytic ability of MTPP (M = Fe, Co, and Ni) to convert CO2 to CO, particularly for FeTPP. Co NPs/FeTPP endowed a high CO faradaic efficiency (FECOmax = 95.5%) in the H cell, and the FECO > 90.0% is in the broad potential range of -0.72 to -1.22 VRHE. In addition, the Co NPs/FeTPP achieved 145.4 mA cm-2 at a lower potential of -0.70 VRHE with an FECO of 94.7%, and the CO partial currents increased quickly to reach 202.2 mA cm-2 at -0.80 VRHE with an FECO of 91.6% in the flow cell. It is confirmed that Co NPs are necessary for hybrid catalysts to get superior electrocatalytic activity; Co NPs also can accelerate H2O dissociation and boost the proton supply capacity to hasten the proton-coupled electron-transfer process, effectively adjusting the adsorption strength of the reaction intermediates.

4.
Environ Sci Technol ; 58(1): 660-670, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38110333

RESUMEN

To effectively remove high concentrations of mercury in a high sulfur atmosphere of nonferrous smelting flue gas, a novel two-dimensional CuS-MOF (CuS-BDC-2D) material is synthesized by anchoring S to Cu sites in the Cu-BDC MOF. The highly dispersed CuS active sites and MOF framework structural properties in CuS-BDC-2D enable efficiently collaborate in capturing mercury. CuS-BDC-2D exhibits a layered floral structure with high specific surface area and thermal stability, with poor crystallinity. Compared to CuS and the three-dimensional CuS-MOF (CuS-BDC-3D) structure, CuS-BDC-2D demonstrates significantly higher mercury capture capacity due to the high exposure of active sites and defects sites in the two-dimensional material. Moreover, CuS-BDC-2D exhibits excellent resistance to sulfur, maintaining its high efficiency in removing Hg0 even at high levels of sulfur dioxide (SO2), such as 5000-20,000 ppm. The superior performance of CuS-BDC-2D makes it suitable for controlling mercury emissions in actual nonferrous smelting flue gas. This discovery also paves the way for the development of new mercury adsorbents, which can guide future advancements in this field.


Asunto(s)
Mercurio , Mercurio/química , Adsorción , Metales , Dióxido de Azufre , Azufre
5.
Heliyon ; 9(10): e20342, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37780772

RESUMEN

Purpose: The high rates of disability and mortality due to postoperative complications of hip fractures in the elderly, especially the oldest-old individuals, have become an increasingly serious global public health concern. This study aimed to establish a nomogram prediction model and analyze the economic burden to guide clinical decision-making and improve patient prognosis. Methods: Data of 514 patients aged over 80 years with hip fractures who received surgical treatment were retrospectively collected, and the patients were divided into training and validation cohorts. Independent risk factors for postoperative complications were identified based on logistic regression analysis, and a nomogram was constructed. The model was evaluated for its discrimination and consistency using receiver operating characteristic (ROC) curves and calibration curves, and for its clinical benefit using decision curve analysis (DCA). The economic burden was analyzed using propensity score matching (PSM). Results: The American Society of Anesthesiologists (ASA) classification ≥Ⅲ, anemia, male sex, diabetes mellitus, and the number of comorbidities were found to be independent risk factors for postoperative complications in oldest-old patients with hip fracture (all P < 0.05). The areas under the curve (AUC) of the nomogram prediction model for the training and validation cohorts were 0.743 and 0.767, respectively, indicating reliable discrimination. The calibration curves and DCA showed that the model has good consistency and high benefits. The direct economic burden of postoperative complications for the patients was US$1045.10. Conclusions: The nomogram model can accurately quantify the risk of postoperative complications among oldest-old patients with hip fractures and guide clinical professionals to implement early and targeted preventive treatment for high-risk patients.

6.
Inorg Chem ; 62(40): 16426-16434, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37750677

RESUMEN

Metal-organic frameworks (MOFs) are emerging as promising candidates for electrochemical glucose sensing owing to their ordered channels, tunable chemistry, and atom-precision metal sites. Herein, the efficient nonenzymatic electrochemical glucose sensing is achieved by taking advantage of Ni(II)-based metal-organic frameworks (Ni(II)-MOFs) and acquiring the ever-reported fastest response time. Three Ni(II)-MOFs ({[Ni6L2(H2O)26]4H2O}n (CTGU-33), {Ni(bib)1/2(H2L)1/2(H2O)3}n (CTGU-34), {Ni(phen)(H2L)1/2(H2O)2}n (CTGU-35)) have been synthesized for the first time, which use benzene-1,2,3,4,5,6-hexacarboxylic acid (H6L) as an organic ligand and introduce 1,4-bis(1-imidazoly)benzene (bib) or 1,10-phenanthroline (phen) as spatially auxiliary ligands. Bib and phen convert the coordination mode of CTGU-33, affording structural dimensions from 2D of CTGU-33 to 3D of CTGU-34 or 1D of CTGU-35. By tuning the dimension of the skeleton, CTGU-34 with 3D interconnected channels exhibits an ultrafast response of less than 0.4 s, which is superior to the existing nonenzymatic electrochemical sensors. Additionally, a low detection limit of 0.12 µM (S/N = 3) and a high sensitivity of 1705 µA mM-1 cm-2 are simultaneously achieved. CTGU-34 further showcases desirable anti-interference and cycling stability, which demonstrates a promising application prospect in the real-time detection of glucose.

7.
Chem Commun (Camb) ; 59(71): 10672-10675, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37581899

RESUMEN

A series of seaweed-like heterogeneous Co3(PO4)2/Ni3(PO4)2/MOF-74-x electrocatalysts were synthesized via a hydrothermal method. The optimal composite exhibits excellent catalytic performance toward methanol/ethanol oxidation reactions (MOR/EOR) with peak current densities reaching 27.5 and 32.6 mA cm-2, respectively. This work heralds the advent of more efficient heterogeneous electrocatalysts for DAFCs and other energy conversion systems.

8.
Inorg Chem ; 62(26): 10256-10262, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37344358

RESUMEN

Two-dimensional metal-organic framework (MOF) crystalline materials possess promising potential in the electrochemical sensing process owing to their tunable structures, high specific surface area, and abundant metal active sites; however, developing MOF-based nonenzymatic glucose (Glu) sensors which combine electrochemical activity and environmental stability remains a challenge. Herein, utilizing the tripodic nitrogen-bridged 1,3,5-tris(1-imidazolyl) benzene (TIB) linker, Co2+ and Ni2+, two 2D isomorphic crystalline materials, including Co/Ni-MOF {[Co (TIB)]·2BF4} (CTGU-31) and {[Ni(TIB)]·2NO3} (CTGU-32), with a binodal (3, 6)-connected kgd topological net were firstly synthesized and fabricated with conducting acetylene black (AB). When modified on a glassy carbon electrode, the optimized AB/CTGU-32 (1:1) electrocatalyst demonstrated a higher sensitivity of 2.198 µA µM-1 cm-2, a wider linear range from 10 to 4000 µM, and a lower detection limit (LOD) value (0.09 µM, S/N = 3) compared to previously MOF-based Glu sensors. Moreover, AB/CTGU-32 (1:1) exhibited desirable stability for at least 2000 s during the electrochemical process. The work indicates that MOF-based electrocatalysts are a promising candidate for monitoring Glu and demonstrate their potential for preliminary screening for diabetes.


Asunto(s)
Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Carbono/química , Níquel/química , Electrodos , Acetileno , Glucosa/química
9.
Plant Physiol Biochem ; 200: 107801, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37269822

RESUMEN

Phosphate (Pi) deficiency is a common stress that limits plant growth and development. Plants exhibit a variety of Pi starvation responses (PSRs), including anthocyanin accumulation. The transcription factors of the PHOSPHATE STARVATION RESPONSE (PHR) family, such as AtPHR1 in Arabidopsis, play central roles in the regulation of Pi starvation signaling. Solanum lycopersicum PHR1-like 1 (SlPHL1) is a recently identified PHR involved in PSR regulation in tomato, but the detailed mechanism of its participation in Pi starvation-inducing anthocyanin accumulation remains unclear. Here we found that overexpression of SlPHL1 in tomato increases the expression of genes associated with anthocyanin biosynthesis, thereby promoting anthocyanin biosynthesis, but silencing SlPHL1 with Virus Induced Gene Silencing (VIGS) attenuated low phosphate (LP) stress-induced anthocyanin accumulation and expression of the biosynthesis-related genes. Notably, SlPHL1 is able to bind the promoters of genes Flavanone 3-Hydroxylase (SlF3H), Flavanone 3'-Hydroxylase (SlF3'H), and Leucoanthocyanidin Dioxygenase (SlLDOX) by yeast one-hybrid (Y1H) analysis. Furthermore, Electrophoretic Mobility Shift Assay (EMSA) and transient transcript expression assay showed that PHR1 binding t (sequence (P1BS) motifs located on the promoters of these three genes are critical for SlPHL1 binding and enhancing the gene transcription. Additionally, allogenic overexpression of SlPHL1 could promote anthocyanin biosynthesis in Arabidopsis under LP conditions through the similar mechanism to AtPHR1, suggesting that SlPHL1 might be functionally conserved with AtPHR1 in this process. Taken together, SlPHL1 positively regulates LP-induced anthocyanin accumulation by directly promoting the transcription of SlF3H, SlF3'H and SlLDOX. These findings will contribute to understanding the molecular mechanism of PSR in tomato.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Solanum lycopersicum , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Solanum lycopersicum/genética , Antocianinas/metabolismo , Regulación hacia Arriba , Fosfatos/metabolismo , Regulación de la Expresión Génica de las Plantas , Factores de Transcripción/genética
10.
Cancer Cell ; 41(6): 1152-1169.e7, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-37172580

RESUMEN

Immune checkpoint inhibitor (ICI) therapy can induce complete responses in mismatch repair-deficient and microsatellite instability-high (d-MMR/MSI-H) colorectal cancers (CRCs). However, the underlying mechanism for pathological complete response (pCR) to immunotherapy has not been completely understood. We utilize single-cell RNA sequencing (scRNA-seq) to investigate the dynamics of immune and stromal cells in 19 patients with d-MMR/MSI-H CRC who received neoadjuvant PD-1 blockade. We found that in tumors with pCR, there is a concerted decrease in CD8+ Trm-mitotic, CD4+ Tregs, proinflammatory IL1B+ Mono and CCL2+ Fibroblast following treatment, while the proportions of CD8+ Tem, CD4+ Th, CD20+ B, and HLA-DRA+ Endothelial cells increase. Proinflammatory features in the tumor microenvironment mediate the persistence of residual tumors by modulating CD8+ T cells and other response-associated immune cell populations. Our study provides valuable resources and biological insights into the mechanism of successful ICI therapy and potential targets for improving treatment efficacy.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Humanos , Receptor de Muerte Celular Programada 1 , Linfocitos T CD8-positivos/patología , Reparación de la Incompatibilidad de ADN , Células Endoteliales , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Inestabilidad de Microsatélites , Microambiente Tumoral
11.
Cancer Med ; 12(12): 13811-13820, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37132165

RESUMEN

BACKGROUND: This study aims to provide a theoretical basis for the prevention of oral cancer by analyzing the epidemiological trends of oral cancer. MATERIALS AND METHODS: The data on oral cancer from 1990 to 2019 were extracted from the Global Burden of Disease 2019 database. The incidence, mortality, disability-adjusted life years (DALYs), and age-standardized rate as well as attributable risk factors of oral cancer were used for the analysis. Estimated annual percentage change (EAPC) was calculated to describe the changes in age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and age-standardized DALYs rate (ASDR). RESULTS: The global ASIR of oral cancer showed an increasing trend from 1990 to 2019. ASIR in high SDI regions showed a decreasing trend during the studied period, with high SDI regions having the lowest ASMR in 2019. In 2019, the highest ASIR, ASMR, and ASDR were detected in South Asia. At the national level, Pakistan had the highest ASMR and ASDR in 2019. The increasing disease burden was observed in younger populations aged below 45 during the studied period. Smoking and alcohol use still exerted profound impacts on the oral cancer burden, with South Asia having the greatest increase in the percentage of deaths due to oral cancer attributable to chewing tobacco from 1990 to 2019. CONCLUSION: In conclusion, there is a large variability in the temporal and spatial burden of oral cancer, and it is essential for priority countries to take targeted intervention policies and measures to reduce the disease burden of oral cancer. In addition, the oral cancer burden caused by attributable risk factors should also receive close attention.


Asunto(s)
Neoplasias de la Boca , Humanos , Anciano , Neoplasias de la Boca/epidemiología , Neoplasias de la Boca/etiología , Factores de Riesgo , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Fumar , Sur de Asia , Salud Global , Incidencia
12.
Dalton Trans ; 52(23): 7819-7827, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37212634

RESUMEN

Transition metal sulfides are low-cost oxygen evolution reaction (OER) electrocatalysts that can potentially substitute noble metal catalysts. However, the adsorption process of their OER is impeded by their intrinsic poor catalytic activity. Constructing heterojunction and vacancy defects in transition metal sulfides is an efficient method to promote the process of oxygen evolution. Herein, a facile approach based on in situ sulfurization of metal-organic gels (MOGs) and a short-time plasma treatment was developed to fabricate vacancy-modified polymetallic sulfides heterojunction. The synergistic effect of the multi-component heterojunction and sulfur vacancy contributed greatly to improving the electron migration efficiency and OER ability of the electrocatalyst. As a result, the optimum oxygen evolution activity was achieved with appropriate surface vacancy concentrations by regulating the plasma radio frequency powers. The plasma-treated catalyst under 400 W showed the best OER performance (lower overpotential of 235 mV in 1 M KOH solution with the Tafel slope of 31 mV dec-1) and good durability over 11 h of chronopotentiometry testing. This work sheds new light on constructing multimetal-based heterojunction electrocatalysts with rich vacancy defects for oxygen evolution reactions.

13.
Hypertens Res ; 46(8): 1949-1960, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37258626

RESUMEN

We detect the antihypertensive effects of maximakinin (MK) on renal hypertensive rats (RHRs) and further research the influence of MK on vascular smooth muscle cells (VSMCs) to explore its hypotensive mechanism. The effects of MK on arterial blood pressure were observed in RHRs. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assays were performed to detect the effect of MK on VSMC viability. Western blot and flow cytometry were used to investigate the influence of MK on intracellular Ca2+ levels and protein expression changes in VSMCs. In addition, specific protein inhibitors were applied to confirm the involvement of Ca2+-related signaling pathways induced by MK in VSMCs. MK showed a more significant antihypertensive effect than bradykinin in RHRs. MK significantly decreased intracellular Ca2+ concentrations. Furthermore, MK significantly induced the phosphorylation of signaling molecules, including extracellular signal-regulated kinase 1/2 (ERK1/2), P38, AMP-activated protein kinase (AMPK) and Akt in VSMCs. Moreover, only ERK1/2 inhibitor U0126 and AMPK inhibitor Compound C completely restored the decreased intracellular Ca2+ level induced by MK, and further research demonstrated that AMPK functioned upstream of ERK1/2 following exposure to MK. Finally, HOE-140, an inhibitor of the bradykinin B2 receptors (B2Rs), was applied to investigate the potential targets of MK in VSMCs. HOE-140 significantly blocked the AMPK/ERK1/2 pathway induced by MK, suggesting that the B2Rs might play an important role in MK-induced AMPK and ERK1/2 activation. MK significantly reduces blood pressure in RHRs. MK exerts its antihypertensive effect by activating the B2Rs and downstream AMPK/ERK1/2 pathways, leading to significantly reduced Ca2+ levels in VSMCs.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Músculo Liso Vascular , Ratas , Animales , Músculo Liso Vascular/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Sistema de Señalización de MAP Quinasas , Antihipertensivos/farmacología , Bradiquinina/farmacología , Bradiquinina/metabolismo , Células Cultivadas , Transducción de Señal , Fosforilación , Miocitos del Músculo Liso/metabolismo
14.
Gastroenterol Rep (Oxf) ; 11: goad014, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37056281

RESUMEN

Background: The tumor microenvironment plays an essential role in the therapeutic response to immunotherapy. It is necessary to identify immune cell infiltration (ICI) subtypes for evaluating prognosis and therapeutic benefits. This study aimed to evaluate the ICI score as an effective prognostic biomarker for immune response. Methods: The cell-type identification by estimating relative subsets of RNA transcripts and the estimation of stromal and immune cells in malignant tumors using expression methods were used to analyse ICI landscapes in 161 colorectal cancer (CRC) samples with patients' clinical and prognostic data, RNA sequencing data, and whole-exome sequencing data from the Sixth Affiliated Hospital, Sun Yat-sen University (Guangzhou, China). Statistical analysis and data processing were conducted to calculate ICI scores, and to analyse the prognosis of CRC patients with different ICI scores and other features. A similar analysis with RNA sequencing and clinical data of colon adenocarcinoma (COAD) samples from The Cancer Genome Atlas (TCGA) database was conducted to confirm the correctness of the findings. Results: The high-ICI score group with a better prognosis (hazard ratio [HR], 2.19; 95% confidence interval [CI], 1.03-4.64; log-rank test, P = 0.036) was characterized by the increased tumor mutational burden and interleukin-17 (IL-17) signaling pathway. Significant differences in the prognosis and the expression levels of immune checkpoints and chemokine marker genes were found between the two ICI score groups. For COAD samples from TCGA, the results also showed a significant difference in patients' prognosis between the two ICI score groups (HR, 1.72; 95% CI, 1.00-2.96; log-rank test, P = 0.047). Conclusions: Tumor heterogeneity induced differences in identifying ICI subtypes of CRC patients. The ICI score may serve as an effective biomarker for predicting prognosis, help identify new therapeutic markers for CRC, and develop novel effective immune checkpoint blockade therapies.

15.
Molecules ; 28(6)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36985658

RESUMEN

The flavonoids in Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) have high medicinal value. However, because of slow growth and harsh ecological environments, T. hemsleyanum is currently an endangered species. In light of this, we present a detailed hairy root induction procedure as a promising alternative to true roots with medicinal value. The percentage of explants induced by Agrobacterium rhizogenes (A. rhizogenes) to produce hairy roots out of the total number of explants infected (induction rate 1) was 95.83 ± 7.22%, and the proportion of hairy roots that contained Rol B fragments among all the hairy roots with or without Rol B fragments (positive rate) was 96.57 ± 1.72%. The transformation was further confirmed by the expression of the GUS protein. A high-productive hairy root line was screened for the comparative profiling of six flavonoids with true roots using high-performance liquid chromatography (HPLC). The contents of (+)-catechin, (-)-epicatechin, neochlorogenic acid, luteolin-6-C-glucoside, and orientin were 692.63 ± 127.24, 163.34 ± 31.86, 45.95 ± 3.46, 209.68 ± 6.03, and 56.82 ± 4.75 µg/g dry weight (DW) of 30-day-old hairy roots, respectively, which were higher than those of 3-year-old true roots. Hairy roots have stronger antioxidant activity than true roots. Overall, the hairy roots of T. hemsleyanum could serve as promising alternative sources for the production of flavonoids with medicinal uses.


Asunto(s)
Catequina , Vitaceae , Flavonoides/metabolismo , Raíces de Plantas/metabolismo , Catequina/metabolismo
16.
Biomolecules ; 13(3)2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36979467

RESUMEN

Tetrastigma hemsleyanum Diels et Gilg (T. hemsleyanum) is an extensively used Chinese folk herb with multiple bioactivities. Among these bioactivities, flavonoids are recognized as the representative active ingredients. We previously found an elevated accumulation of flavonoids in T. hemsleyanum under water stress; however, the mechanism remains unclear. R2R3-MYB transcription factors play vital roles in the plant response to environmental stress and the regulation of secondary metabolites. Herein, a systematic transcriptome identification of R2R3-MYB family genes under water stress in T. hemsleyanum was performed to explore their potential function in the biosynthesis of flavonoids. A total of 26 R2R3-MYB genes were identified, most of which were clustered into functional branches of abiotic stress. ThMYB4 and ThMYB7 were then screened out to be associated with the biosynthesis of flavonoids through a protein-protein interaction prediction. An expression correlation analysis based on RNA-seq further confirmed that ThMYB4 and ThMYB7 were positively related to the flavonoid biosynthetic pathway genes of T. hemsleyanum. In ThMYB4- and ThMYB7-overexpression hairy roots, it was found that the expression of ThCHS and ThCHI was significantly increased, suggesting that ThMYB4 and ThMYB7 may act as regulators in flavonoid biosynthesis. This will shed new light on the promotion of flavonoid production and the medicinal value of T. hemsleyanum by manipulating transcription factors.


Asunto(s)
Genes myb , Proteínas de Plantas , Humanos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Deshidratación , Flavonoides/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas
17.
Int J Biol Macromol ; 235: 123798, 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-36841391

RESUMEN

Ganoderma lucidum polysaccharides (GLP) attract growing attention due to their remarkable bioactivities, but the low content in raw materials remains a bottleneck severely restricting their application. We previously found a higher polysaccharides accumulation in Ganoderma lucidum cultured in continuous cropping soil, and soil symbiotic fungi are presumed as the key among many factors. Herein, 33 symbiotic fungi were isolated from the soil, and fungal elicitors were prepared to investigate their biotic eliciting effect on GLP biosynthesis. Most elicitors were found to significantly improve GLP production, among which the NO.16 molecularly identified as Penicillium citrinum, exhibited the optimum eliciting effect with GLP yield increasing by 3.4 times. Differences in the biosynthetic pathway genes expressions and the monosaccharide components of GLP were further analyzed. The transcriptions of the main genes of GLP biosynthetic pathway were up-regulated under PCE treatments, suggesting it improves GLP production by activating transcriptions of the biosynthetic pathway genes. Moreover, PCE eliciting significantly altered the monosaccharide compositions of GLP with Gal, Man, GalA, GlcA, and Fuc increasing by 8.17 %, 5.68 %, 5.41 %, 2.66 %, and 1.51 % respectively, but Glc decreased by 23.43 %, which may result in the activity change. It can serve as a new strategy to improve GLP production.


Asunto(s)
Ganoderma , Reishi , Humanos , Masculino , Vías Biosintéticas , Polisacáridos , Monosacáridos
18.
Sci Adv ; 8(51): eade1383, 2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36563156

RESUMEN

Radical-ionic metal-organic frameworks (MOFs) have unique optical, magnetic, and electronic properties. These radical ions, forcibly formed by external stimulus-induced redox processes, are structurally unstable and have short radical lifetimes. Here, we report two naphthalenediimide-based (NDI-based) Ca-MOFs: DGIST-6 and DGIST-7. Neutral DGIST-6, which is generated first during solvothermal synthesis, decomposes and is converted into radical-anionic DGIST-7. Cofacial (NDI)2•- and (NDI)22- dimers are effectively stabilized in DGIST-7 by electron delocalization and spin-pairing as well as dimethylammonium counter cations in their pores. Single-crystal x-ray diffractometry was used to visualize redox-associated structural transformations, such as changes in centroid-to-centroid distance. Moreover, the unusual rapid reduction of oxidized DGIST-7 into the radical anion upon infrared irradiation results in effective and reproducible photothermal conversion. This study successfully illustrated the strategic use of in situ prepared cofacial ligand dimers in MOFs that facilitate the stabilization of radical ions.

19.
Molecules ; 27(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36432126

RESUMEN

Polysaccharides, which can be affected by different preparations, play a crucial role in the biological function of Paecilomyces hepiali (PHPS) as a health food. To explore high-valued polysaccharides and reduce the negative influence of human involvement, a green tailorable deep eutectic solvent (DES) was applied to optimize the extraction of polysaccharides (PHPS-D), followed by the evaluation of the structural properties and immunomodulation by comparison with the hot-water method (PHPS-W). The results indicated that the best system for PHPS-D was a type of carboxylic acid-based DES consisting of choline chloride and succinic acid in the molar ratio of 1:3, with a 30% water content. The optimal condition was as follows: liquid-solid ratio of 50 mL/g, extraction temperature of 85 °C, and extraction time of 1.7 h. The actual PHPS-D yield was 12.78 ± 0.17%, which was obviously higher than that of PHPS-W. The structural characteristics suggested that PHPS-D contained more uronic acid (22.34 ± 1.38%) and glucose (40.3 ± 0.5%), with a higher molecular weight (3.26 × 105 g/mol) and longer radius of gyration (78.2 ± 3.6 nm), as well as extended chain conformation, compared with PHPS-W, and these results were confirmed by AFM and SEM. Immunomodulatory assays suggested that PHPS-D showed better performance than PHPS-W regarding pinocytic activity and the secretion of NO and pro-inflammatory cytokines (IL-6, TNF-α and IL-1ß) by activating the corresponding mRNA expression in RAW264.7 cells. This study showed that carboxylic acid-based DES could be a promising tailorable green system for acidic polysaccharide preparation and the valorization of P. hepiali in functional foods.


Asunto(s)
Disolventes Eutécticos Profundos , Polisacáridos , Humanos , Solventes/química , Polisacáridos/farmacología , Agua/química , Inmunomodulación , Ácidos Carboxílicos
20.
Plants (Basel) ; 11(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36235328

RESUMEN

Anoectochilus roxburghii (Wall.) Lindl has been used in Chinese herbal medicine for treating various ailments. However, its wild resources are endangered, and artificial cultivation of the plant is limited by the low regeneration rate of conventional propagation methods. The lack of A. roxburghii resources is detrimental to the commercial production of the plant and kinsenoside, which is unique to Anoectochilus species. To develop highly efficient methods for A. roxburghii micropropagation and find alternative resources for kinsenoside production, we created an induction, proliferation, and regeneration of PLBs (IPR-PLB) protocol for A. roxburghii. We also analyzed the kinsenoside and flavonoid contents during the induction and proliferation of PLBs. The best media of IPR-PLB for PLB induction and proliferation (secondary PLB induction and proliferation), shoot formation, and rooting medium were Murashige and Skoog (MS) + 3 mg/L 6-benzylaminopurine (6-BA) + 0.5 mg/L naphthaleneacetic acid (NAA) + 0.8 mg/L zeatin (ZT) + 0.2 mg/L 2,4-dichlorophenoxyacetic acid (2, 4-D), MS + 3 mg/L 6-BA + 0.5 mg/L NAA, and MS + 0.5 mg/L NAA, respectively. On these optimized media, the PLB induction rate was 89 ± 2.08%, secondary PLB induction rate was 120 ± 5%, secondary PLB proliferation rate was 400 ± 10% and 350 ± 10 % in terms of the quantity and biomass at approximately 1 month, shoot induction rate was 10.5 shoots/PLB mass, and root induction rate was 98%. All plantlets survived after acclimation. Darkness or weak light were essential for PLB proliferation, and light was crucial for PLB differentiation on these optimized media. The kinsenoside contents of PLBs and secondary PLBs were 10.38 ± 0.08 and 12.30 ± 0.08 mg/g fresh weight (FW), respectively. Moreover, the peak kinsenoside content during the proliferation of secondary PLBs was 34.27 ± 0.79 mg/g FW, which was slightly lower than that of the whole plant (38.68 ± 3.12 mg/g FW). Two flavonoids exhibited tissue- or temporal-specific accumulation patterns, and astragalin accumulated exclusively during the first 2 weeks of cultivation. The IPR-PLB protocol for A. roxburghii may facilitate the efficient micropropagation of A. roxburghii plants. Furthermore, the PLBs are a good alternative resource for kinsenoside production.

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