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1.
Nat Immunol ; 21(12): 1540-1551, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33020660

RESUMO

The metabolic challenges present in tumors attenuate the metabolic fitness and antitumor activity of tumor-infiltrating T lymphocytes (TILs). However, it remains unclear whether persistent metabolic insufficiency can imprint permanent T cell dysfunction. We found that TILs accumulated depolarized mitochondria as a result of decreased mitophagy activity and displayed functional, transcriptomic and epigenetic characteristics of terminally exhausted T cells. Mechanistically, reduced mitochondrial fitness in TILs was induced by the coordination of T cell receptor stimulation, microenvironmental stressors and PD-1 signaling. Enforced accumulation of depolarized mitochondria with pharmacological inhibitors induced epigenetic reprogramming toward terminal exhaustion, indicating that mitochondrial deregulation caused T cell exhaustion. Furthermore, supplementation with nicotinamide riboside enhanced T cell mitochondrial fitness and improved responsiveness to anti-PD-1 treatment. Together, our results reveal insights into how mitochondrial dynamics and quality orchestrate T cell antitumor responses and commitment to the exhaustion program.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Dinâmica Mitocondrial/imunologia , Biomarcadores , Epigênese Genética , Epigenômica , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Mitofagia , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Niacinamida/farmacologia , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Estresse Fisiológico , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(25): e2322403121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38865273

RESUMO

Fluorine magnetic resonance imaging (19F-MRI) is particularly promising for biomedical applications owing to the absence of fluorine in most biological systems. However, its use has been limited by the lack of safe and water-soluble imaging agents with high fluorine contents and suitable relaxation properties. We report innovative 19F-MRI agents based on supramolecular dendrimers self-assembled by an amphiphilic dendrimer composed of a hydrophobic alkyl chain and a hydrophilic dendron. Specifically, this amphiphilic dendrimer bears multiple negatively charged terminals with high fluorine content, which effectively prevented intra- and intermolecular aggregation of fluorinated entities via electrostatic repulsion. This permitted high fluorine nuclei mobility alongside good water solubility with favorable relaxation properties for use in 19F-MRI. Importantly, the self-assembling 19F-MRI agent was able to encapsulate the near-infrared fluorescence (NIRF) agent DiR and the anticancer drug paclitaxel for multimodal 19F-MRI and NIRF imaging of and theranostics for pancreatic cancer, a deadly disease for which there remains no adequate early detection method or efficacious treatment. The 19F-MRI and multimodal 19F-MRI and NIRF imaging studies on human pancreatic cancer xenografts in mice confirmed the capability of both imaging modalities to specifically image the tumors and demonstrated the efficacy of the theranostic agent in cancer treatment, largely outperforming the clinical anticancer drug paclitaxel. Consequently, these dendrimer nanosystems constitute promising 19F-MRI agents for effective cancer management. This study offers a broad avenue to the construction of 19F-MRI agents and theranostics, exploiting self-assembling supramolecular dendrimer chemistry.


Assuntos
Dendrímeros , Flúor , Nanomedicina Teranóstica , Dendrímeros/química , Animais , Nanomedicina Teranóstica/métodos , Humanos , Camundongos , Flúor/química , Paclitaxel/química , Paclitaxel/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Linhagem Celular Tumoral , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/terapia , Imagem por Ressonância Magnética de Flúor-19/métodos , Camundongos Nus , Meios de Contraste/química
3.
Nature ; 577(7788): 79-84, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31853069

RESUMO

Water lilies belong to the angiosperm order Nymphaeales. Amborellales, Nymphaeales and Austrobaileyales together form the so-called ANA-grade of angiosperms, which are extant representatives of lineages that diverged the earliest from the lineage leading to the extant mesangiosperms1-3. Here we report the 409-megabase genome sequence of the blue-petal water lily (Nymphaea colorata). Our phylogenomic analyses support Amborellales and Nymphaeales as successive sister lineages to all other extant angiosperms. The N. colorata genome and 19 other water lily transcriptomes reveal a Nymphaealean whole-genome duplication event, which is shared by Nymphaeaceae and possibly Cabombaceae. Among the genes retained from this whole-genome duplication are homologues of genes that regulate flowering transition and flower development. The broad expression of homologues of floral ABCE genes in N. colorata might support a similarly broadly active ancestral ABCE model of floral organ determination in early angiosperms. Water lilies have evolved attractive floral scents and colours, which are features shared with mesangiosperms, and we identified their putative biosynthetic genes in N. colorata. The chemical compounds and biosynthetic genes behind floral scents suggest that they have evolved in parallel to those in mesangiosperms. Because of its unique phylogenetic position, the N. colorata genome sheds light on the early evolution of angiosperms.


Assuntos
Genoma de Planta , Nymphaea/genética , Filogenia , Flores/genética , Flores/metabolismo , Nymphaea/metabolismo , Odorantes/análise
4.
Proc Natl Acad Sci U S A ; 120(7): e2215308120, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36745793

RESUMO

Drug delivery systems (DDSs) that can overcome tumor heterogeneity and achieve deep tumor penetration are challenging to develop yet in high demand for cancer treatment. We report here a DDS based on self-assembling dendrimer nanomicelles for effective and deep tumor penetration via in situ tumor-secreted extracellular vesicles (EVs), an endogenous transport system that evolves with tumor microenvironment. Upon arrival at a tumor, these dendrimer nanomicelles had their payload repackaged by the cells into EVs, which were further transported and internalized by other cells for delivery "in relay." Using pancreatic and colorectal cancer-derived 2D, 3D, and xenograft models, we demonstrated that the in situ-generated EVs mediated intercellular delivery, propagating cargo from cell to cell and deep within the tumor. Our study provides a new perspective on exploiting the intrinsic features of tumors alongside dendrimer supramolecular chemistry to develop smart and effective DDSs to overcome tumor heterogeneity and their evolutive nature thereby improving cancer therapy.


Assuntos
Dendrímeros , Vesículas Extracelulares , Neoplasias , Humanos , Preparações Farmacêuticas/análise , Dendrímeros/química , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Microambiente Tumoral
5.
Nano Lett ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38525903

RESUMO

The c-axis piezoresistivity is a fundamental and important parameter of graphite, but its value near zero pressure has not been well determined. Herein, a new method for studying the c-axis piezoresistivity of van der Waals materials near zero pressure is developed on the basis of in situ scanning electron microscopy and finite element simulation. The c-axis piezoresistivity of microscale highly oriented pyrolytic graphite (HOPG) is found to show a large value of 5.68 × 10-5 kPa-1 near zero pressure and decreases by 2 orders of magnitude to the established value of ∼10-7 kPa-1 when the pressure increases to 200 MPa. By modulating the serial tunneling barrier model on the basis of the stacking faults, we describe the c-axis electrical transport of HOPG under compression. The large c-axis piezoresistivity near zero pressure and its large decrease in magnitude with pressure are attributed to the rapid stiffening of the electromechanical properties under compression.

6.
Nano Lett ; 24(10): 3237-3242, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38437641

RESUMO

Traditional semiconductor quantum dots of groups II-VI are key ingredients of next-generation display technology. Yet, the majority of them contain toxic heavy-metal elements, thus calling for alternative light-emitting materials. Herein, we have explored three novel categories of multicomponent compounds, namely, tetragonal II-III2-VI4 porous ternary compounds, cubic I2-II3-VI4 ternary compounds, and cubic I-II-III3-V4 quaternary compounds. This is achieved by judicious introduction of a "super atom" perspective and concurrently varying the solid-state lattice packing of involved super atoms or the population of surrounding counter cations. Based on first-principles calculations of 392 candidate materials with designed crystal structures, 53 highly stable materials have been screened. Strikingly, 34 of them are direct-bandgap semiconductors with emitting wavelengths covering the near-infrared and visible-light regions. This work provides a comprehensive database of highly efficient light-emitting materials, which may be of interest for a broad field of optoelectronic applications.

7.
New Phytol ; 244(3): 914-933, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39223898

RESUMO

Trichomes are specialized epidermal outgrowths covering the aerial parts of most terrestrial plants. There is a large species variability in occurrence of different types of trichomes such that the molecular regulatory mechanism underlying the formation and the biological function of trichomes in most plant species remain unexplored. Here, we used Chrysanthemum morifolium as a model plant to explore the regulatory network in trichome formation and terpenoid synthesis and unravel the physical and chemical roles of trichomes in constitutive defense against herbivore feeding. By analyzing the trichome-related genes from transcriptome database of the trichomes-removed leaves and intact leaves, we identified CmMYC2 to positively regulate both development of T-shaped and glandular trichomes as well as the content of terpenoids stored in glandular trichomes. Furthermore, we found that the role of CmMYC2 in trichome formation and terpene synthesis was mediated by interaction with CmMYBML1. Our results reveal a sophisticated molecular mechanism wherein the CmMYC2-CmMYBML1 feedback inhibition loop regulates the formation of trichomes (non-glandular and glandular) and terpene biosynthesis, collectively contributing to the enhanced resistance to Spodoptera litura larvae feeding. Our findings provide new insights into the novel regulatory network by which the plant synchronously regulates trichome density for the physical and chemical defense against herbivory.


Assuntos
Chrysanthemum , Regulação da Expressão Gênica de Plantas , Herbivoria , Proteínas de Plantas , Terpenos , Tricomas , Tricomas/metabolismo , Terpenos/metabolismo , Chrysanthemum/genética , Chrysanthemum/metabolismo , Chrysanthemum/fisiologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Animais , Defesa das Plantas contra Herbivoria , Folhas de Planta/metabolismo , Genes de Plantas , Spodoptera/fisiologia
8.
Opt Express ; 32(11): 19665-19675, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859096

RESUMO

This study demonstrates a differential absorption lidar (DIAL) for CO2 that integrates both single-photon direct detection and coherent detection. Based on all-fiber 1572 nm wavelength devices, this compact lidar achieves detection of CO2 concentration, wind field, and single photon aerosol backscattering signal. First, by comparing DIAL with VAISALA-GMP343, the concentration deviation between the two devices is less than 5 ppm, proving the accuracy of the DIAL. Second, through the scanning detection experiment in Chaohu Lake, Hefei, not only the CO2 concentration between single-photon detection and coherent detection but also the wind field was obtained, proving the multifunctionality and stability of the DIAL. Benefiting from the advantages of combined the two detection methods, single photon detection offers 3-km CO2 and aerosol backscattering signals; coherent detection offers a 360-m shorter blind zone and wind field. This DIAL can achieve monitoring of CO2 flux and sudden emissions, which can effectively compensate for the shortages of in-situ sensors and spaceborne systems.

9.
Environ Sci Technol ; 58(32): 14361-14371, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39088841

RESUMO

The photolysis of particulate nitrate (pNO3-) has been suggested to be an important source of nitrous acid (HONO) in the troposphere. However, determining the photolysis rate constant of pNO3- (jpNO3-) suffers from high uncertainty. Prior laboratory measurements of jpNO3- using aerosol filters have been complicated by the "shadow effect"─a phenomenon of light extinction within aerosol layers that potentially skews these measurements. We developed a method to correct the shadow effect on the photolysis rate constant of pNO3- for HONO production (jpNO3- â†’ HONO) using aerosol filters with identical chemical compositions but different aerosol loadings. We applied the method to quantify jpNO3- â†’ HONO over the North China Plain (NCP) during the winter haze period. After correcting for the shadow effect, the normalized average jpNO3- â†’ HONO at 5 °C increased from 5.89 × 10-6 s-1 to 1.72 × 10-5 s-1. The jpNO3- â†’ HONO decreased with increasing pH and nitrate proportions in PM2.5 and had no correlation with nitrate concentrations. A parametrization for jpNO3- â†’ HONO was developed for model simulation of HONO production in NCP and similar environments.


Assuntos
Poluentes Atmosféricos , Atmosfera , Nitratos , Ácido Nitroso , Fotólise , Nitratos/química , Atmosfera/química , Ácido Nitroso/química , Poluentes Atmosféricos/química , Aerossóis
10.
Environ Res ; 252(Pt 1): 118843, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582429

RESUMO

Recently, the newly discovered anaerobic ammonium oxidation coupled with iron reduction (i.e., Feammox) has been proven to be a widespread nitrogen (N) loss pathway in ecosystems and has an essential contribution to gaseous N loss in paddy soil. However, the mechanism of iron-nitrogen coupling transformation and the role of iron-reducing bacteria (IRB) in Feammox were poorly understood. This study investigated the Feammox and iron reduction changes and microbial community evolution in a long-term anaerobic incubation by 15N isotope labeling combined with molecular biological techniques. The average rates of Feammox and iron reduction during the whole incubation were 0.25 ± 0.04 µg N g-1 d-1 and 40.58 ± 3.28 µg Fe g-1 d-1, respectively. High iron oxide content increased the Feammox rate, but decreased the proportion of Feammox-N2 in three Feammox pathways. RBG-13-54-9, Brevundimonas, and Pelomonas played a vital role in the evolution of microbial communities. The characteristics of asynchronous changes between Feammox and iron reduction were found through long-term incubation. IRB might not be the key species directly driving Feammox, and it is necessary to reevaluate the role of IRB in Feammox process.


Assuntos
Ferro , Oxirredução , Microbiologia do Solo , Solo , China , Ferro/metabolismo , Solo/química , Bactérias/metabolismo , Compostos de Amônio/análise , Compostos de Amônio/metabolismo
11.
Environ Res ; 251(Pt 2): 118769, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518918

RESUMO

This study aims to thoroughly investigate the impact mode of salinity carried by industrial wastewater on the anaerobic-anoxic-oxic (A2O) sludge in wastewater treatment plants (WWTPs). Through comprehensive investigation of the A2O stage activated sludge (AS) from 19 industrial WWTPs in the downstream area of the Yangtze River, China, A total of 38 samples of anaerobic sludge and oxic sludge were collected and analyzed. We found that salinity stress significantly inhibits the growth of the AS community, particularly evident in the anaerobic sludge community. Furthermore, the high-saline environment induces changes in the structure and functional patterns of the AS community, leading to intensive interactions and resource exchanges among microorganisms. Halophilic microorganisms may play a crucial role in this process, significantly impacting the overall community structure, especially in the oxic sludge community. Additionally, salinity stress not only suppresses the nitrogen transformation potential of the AS but also leads to the accumulation of nitrite, thereby increasing the emission potential of both NO and N2O, exacerbating the greenhouse effect of the A2O process in industrial WWTPs. The findings of this study provide necessary theoretical support for maintaining the long-term stable operation of the A2O sludge system in industrial WWTPs, reducing carbon footprint, and improving nitrogen removal efficiency.


Assuntos
Nitrogênio , Rios , Salinidade , Esgotos , China , Esgotos/microbiologia , Rios/microbiologia , Rios/química , Nitrogênio/metabolismo , Nitrogênio/análise , Microbiota , Eliminação de Resíduos Líquidos/métodos , Resíduos Industriais
12.
J Nanobiotechnology ; 22(1): 2, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38169390

RESUMO

BACKGROUND: Off-targeted distribution of chemotherapeutic drugs causes severe side effects, further leading to poor prognosis and patient compliance. Ligand/receptor-mediated targeted drug delivery can improve drug accumulation in the tumor but it always attenuated by protein corona barriers. RESULTS: To address these problems, a radically different strategy is proposed that can leave the off-targeted drugs inactive but activate the tumor-distributed drugs for cancer-targeting therapy in a tumor microenvironment-independent manner. The feasibility and effectiveness of this strategy is demonstrated by developing an ultrasound (US)-activated prodrug-loaded liposome (CPBSN38L) comprising the sonosensitizer chlorin e6 (Ce6)-modified lipids and the prodrug of pinacol boronic ester-conjugated SN38 (PBSN38). Once CPBSN38L is accumulated in the tumor and internalized into the cancer cells, under US irradiation, the sonosensitizer Ce6 rapidly induces extensive production of intracellular reactive oxygen species (ROS), thereby initiating a cascade amplified ROS-responsive activation of PBSN38 to release the active SN38 for inducing cell apoptosis. If some of the injected CPBSN38L is distributed into normal tissues, the inactive PBSN38 exerts no pharmacological activity on normal cells. CPBSN38L exhibited strong anticancer activity in multiple murine tumor models of colon adenocarcinoma and hepatocellular carcinoma with no chemotherapy-induced side effects, compared with the standard first-line anticancer drugs irinotecan and topotecan. CONCLUSIONS: This study established a side-effect-evitable, universal, and feasible strategy for cancer-targeting therapy.


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias do Colo , Nanopartículas , Fotoquimioterapia , Pró-Fármacos , Humanos , Animais , Camundongos , Lipossomos , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Adenocarcinoma/tratamento farmacológico , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Nanopartículas/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Microambiente Tumoral
13.
Biochem Genet ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305353

RESUMO

Recently, rs9651118 in the MTHFR gene and rs2790 in the TYMS gene have been repeatedly studied for their contribution to cancer risk. However, the results remain conflicting rather than conclusive. Therefore, we here conducted a replication case-control study and a meta-analysis to comprehensively examine the contribution of rs9651118 and rs2790 to cancer risk. A total of 1727 patients with colorectal/gastric/liver (787/460/480) cancer and 800 healthy controls were recruited, and the Sanger sequencing was applied to genotype rs9651118 and rs2790. Besides, a total of 23 eligible studies were included in the following meta-analysis. After Bonferroni correction, the results of case-control study suggested that significant associations between rs9651118 and colorectal cancer (CRC) risk, rs9651118 and gastric cancer (GC) risk, and rs2790 and liver cancer (LC) risk were identified in Hubei Chinese population. The results of meta-analysis indicated that after Bonferroni correction, both rs9651118 and rs2790 were significantly associated with total cancer risk especially in Asian population and based on Sanger sequencing method, rs9651118 was significantly associated with breast cancer (BC) risk, and rs2790 was significantly associated with the risk of CRC and GC. In conclusion, the present findings revealed that the MTHFR gene rs9651118 may participate in the risk of total cancer (especially BC) in Asian population, and the TYMS gene rs2790 may be associated with the risk of total cancer (especially CRC) in Asian population and also the risk of GC in total population.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38551416

RESUMO

Patients with severe traumatic brain injury (sTBI) are at risk of adverse events (AEs) during hospitalization, and providing nursing interventions can help reduce the negative impact of AEs. This study primarily discusses the influence of early cluster nursing intervention on nursing efficacy and AEs in patients with sTBI. We enrolled 109 sTBI patients treated in the First Affiliated Hospital of Shanghai Jiao Tong University School of Medicine between October 2022 to June 2023. We grouped them as follows based on different nursing approaches: regular group (n=52) with routine nursing intervention and research group (n=57) with early cluster nursing intervention. Parameters such as nursing satisfaction, incidence of AEs (bed falls, agitation, indwelling needle withdrawal, and skin loss), and scores of Fugl-Meyer Assessment (FMA), Functional Independence Measure (FIM), Glasgow Coma Scale (GCS), National Institutes of Health Stroke Scale (NIHSS), and quality of life assessment instrument (QOL-100) were comparatively analyzed. The analysis showed a higher nursing satisfaction degree and a lower incidence of AEs in the research group compared with the regular group; in addition, FMA, FIM, GCS, and QOL-100 scores were higher in the research group versus the control group after nursing, while the NIHSS score was lower; all of these differences were statistically significant (P < .05). Therefore, early cluster nursing intervention is highly effective in the care of sTBI patients. It can effectively improve patients' nursing satisfaction and prevent AEs while enhancing their motor function, functional independence, consciousness, neurological function, and quality of life.

15.
J Environ Manage ; 370: 122548, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299115

RESUMO

High-salt textile dyeing wastewater is difficult to treat. Magnetic fields can enhance the biodegradation capacity and extreme environmental adaptabilities of microorganisms. Thus, magnetically enhanced bioreactors are expected to improve the treatment efficiency and stability of high-salt textile dyeing wastewater. Accordingly, a novel Built-in Static Magnetic Field - Biological Aerated Filter (BSMF-BAF) was constructed and investigated for treating actual high-salt textile dyeing wastewater in this study. Two other BAFs packed with traditional and magnetic ceramsite carriers, respectively, were simultaneously operated for comparison. The removal of color, chemical oxygen demand (COD), suspended solid (SS) and acute toxicity were monitored. The activities of key enzymes and microbial community structure were analyzed to reveal possible mechanisms for improving the treatment efficiency of traditional BAF using the BSMF. The results showed that the BSMF-BAF possessed the highest removal efficiencies of color, COD, SS and acute toxicity among the three BAFs. The BSMF induced significant increases in the activities of azoreductase and lignin peroxidase, which were responsible for the degradation of azo compounds in the wastewater and the detoxification of toxic intermediates, respectively. Additionally, the BSMF induced the relative enrichment of potentially effective bacteria and fungi, and it maintained a relatively high abundance of fungi in the microbial community, resulting in a high treatment efficiency.

16.
J Environ Manage ; 351: 119763, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38071921

RESUMO

Rhizosphere is a soil volume of high spatio-temporal heterogeneity and intensive plant-soil-microbial interactions, for which visualization and process quantification is of highest scientific and applied relevance, but still very challenging. A novel methodology for quick assessment of two-dimensional distribution of available phosphorus (P) in rhizosphere was suggested, tested, and development up to the application platform. Available P was firstly trapped by an in-situ diffusive gradients in thin-films (DGT) sampler with precipitated zirconia as the binding gel, and subsequently, the loaded gel was analyzed with an optimized colorimetric imaging densitometry (CID). The imaging platform was established linking: i) DGT, ii) planar optode, and iii) soil zymography techniques to simultaneously determine available P, oxygen, and acid phosphatase in rhizosphere at sub-millimeter spatial scales. The DGT identified available P level in rice rhizosphere were spatially overlapping to the localized redox hotspots and phosphatase activity. The spatial relationship between available P and acid phosphatase activity was dependent on root development. The root radial oxygen loss (ROL) remained active during the experimental observations (2-3 days), while a flux of available P of 10 pg cm-2 s-1 was visualized within 2-3 mm of roots, confirming the correlative response of rice roots to oxygen secretion and P uptake. Summarizing, the established imaging platform is suitable to capture spatial heterogeneity and temporal dynamics of root activities, nutrient bioavailability, ROL and enzyme activities in rhizosphere.


Assuntos
Oryza , Fósforo , Fósforo/metabolismo , Rizosfera , Solo , Oxigênio/metabolismo , Fosfatase Ácida/metabolismo , Raízes de Plantas/metabolismo
17.
Angew Chem Int Ed Engl ; 63(42): e202409653, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39039028

RESUMO

Acridine frameworks stand as pivotal architectural elements in pharmaceuticals and photocatalytic applications, owing to their chemical adaptability, biological activity, and unique excited-state dynamics. Conventional synthetic routes often entail specialized starting materials, anaerobic or moisture-free conditions, and elaborate multi-stage manipulations for incorporating diverse functionalities. Herein, we present a convergent approach integrating photo-excitation of readily available ortho-alkyl nitroarenes with copper-promoted cascade annulation. This innovative system enables an aerobic, one-pot reaction of o-alkyl nitroarenes with arylboronic acids, thereby streamlining the modular construction of a wide array of acridine derivatives with various functional groups. This encompasses symmetrical, unsymmetrical and polysubstituted varieties, some of which are otherwise exceptionally difficult to synthesize. Furthermore, it significantly improves the production of structurally varied acridinium salts, featuring enhanced photophysical properties, high excited state potentials (E*red=2.08-3.15 V), and exhibiting superior performance in intricate photoredox transformations.

18.
J Transl Med ; 21(1): 420, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37381011

RESUMO

Hepatocellular carcinoma (HCC) is one of the most lethal tumor types worldwide. Glycosylation has shown promise in the study of tumor mechanisms and treatment. The glycosylation status of HCC and the underlying molecular mechanisms are still not fully elucidated. Using bioinformatic analysis we obtained a more comprehensive characterization of glycosylation of HCC. Our analysis presented that high glycosylation levels might correlate with tumor progression and poor prognosis. Subsequent Experiments identified key molecular mechanisms for ST6GALNAC4 promoting malignant progression by inducing abnormal glycosylation. We confirmed the contribution of ST6GALNAC4 to proliferation, migration, and invasion in vitro and in vivo. Mechanistic studies revealed that ST6GALNAC4 may be induced abnormal TGFBR2 glycosylation, resulting in the higher protein levels of TGFBR2 and TGF[Formula: see text] pathway increased activation. Our study also provided a further understand of immunosuppressive function of ST6GALNAC4 through T antigen-galectin3+ TAMs axis. This study has provided one such possibility that galectin3 inhibitors might be an acceptable treatment choice for HCC patients with high T antigen expression.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sialiltransferases , Humanos , Antígenos Virais de Tumores , Carcinogênese , Carcinoma Hepatocelular/genética , Glicosilação , Neoplasias Hepáticas/genética , Receptor do Fator de Crescimento Transformador beta Tipo II , Sialiltransferases/genética
19.
J Exp Bot ; 74(4): 1275-1290, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36433929

RESUMO

Jasminum sambac is a well-known plant for its attractive and exceptional fragrance, the flowers of which are used to produce scented tea. Jasmonate (JA), an important plant hormone was first identified in Jasminum species. Jasmine plants contain abundant JA naturally, of which the molecular mechanisms of synthesis and accumulation are not clearly understood. Here, we report a telomere-to-telomere consensus assembly of a double-petal J. sambac genome along with two haplotype-resolved genomes. We found that gain-and-loss, positive selection, and allelic specific expression of aromatic volatile-related genes contributed to the stronger flower fragrance in double-petal J. sambac compared with single- and multi-petal jasmines. Through comprehensive comparative genomic, transcriptomic, and metabolomic analyses of double-petal J. sambac, we revealed the genetic basis of the production of aromatic volatiles and salicylic acid (SA), and the accumulation of JA under non-stress conditions. We identified several key genes associated with JA biosynthesis, and their non-stress related activities lead to extraordinarily high concentrations of JA in tissues. High JA synthesis coupled with low degradation in J. sambac results in accumulation of high JA under typical environmental conditions, similar to the accumulation mechanism of SA. This study offers important insights into the biology of J. sambac, and provides valuable genomic resources for further utilization of natural products.


Assuntos
Jasminum , Jasminum/genética , Perfilação da Expressão Gênica , Transcriptoma , Odorantes
20.
FASEB J ; 36(11): e22589, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36197455

RESUMO

Intestinal inflammation and intestinal barrier damage are important pathological changes in Crohn's disease (CD). Vindoline is a natural monomer with anti-inflammatory effects. We employed CD model mice to explore the effect of Vindoline on CD-like colitis and the possible mechanism. Il-10-deficient (Il-10-/- ) mice and wild-type (WT) mice (both aged 15 weeks, male) were used to explore the effect of Vindoline on colitis and intestinal barrier damage, as well as macrophage-mediated inflammation. Bone-marrow-derived macrophages (BMDMs) and colonic organoids from mice were used to explore the inhibitory effect of Vindoline on macrophage-mediated inflammation and the protective effect on inflammation-induced intestinal barrier damage as well as the possible mechanism. We found that Vindoline significantly ameliorated colitis in CD mice, as evidenced by increased weight change and colon length and decreased the colon macroscopic injury score, histological inflammatory score, and the expression of pro-inflammatory mediators. Vindoline also protected against intestinal barrier damage in CD mice. Furthermore, Vindoline inhibited macrophage-mediated inflammation and protected against inflammation-induced intestinal barrier damage in the coculture system. In addition, Vindoline ameliorated colitis in CD mice by protecting against inflammation-induced intestinal barrier damage, which may be caused by inhibition of MAPK signaling pathway. This protective effect suggests that Vindoline has potential value for clinical application in the treatment of CD.


Assuntos
Colite , Doença de Crohn , Animais , Anti-Inflamatórios/farmacologia , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/patologia , Colo/metabolismo , Doença de Crohn/tratamento farmacológico , Doença de Crohn/patologia , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Inflamação/patologia , Mediadores da Inflamação/farmacologia , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Vimblastina/análogos & derivados
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