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Superoxide anion is thought to be a natural by-product with strong oxidizing ability in all living organisms and was recently found to accumulate in plant meristems to maintain stem cells in the shoot and undifferentiated meristematic cells in the root. Here we show that the DNA demethylase repressor of silencing 1 (ROS1) is one of the direct targets of superoxide in stem cells. The Fe-S clusters in ROS1 are oxidized by superoxide to activate its DNA glycosylase/lyase activity. We demonstrate that superoxide extensively participates in the establishment of active DNA demethylation in the Arabidopsis genome and that ARABIDOPSIS RESPONSE REGULATOR 12 acts downstream of ROS1-mediated superoxide signaling to maintain stem cell fate. Our results provide a mechanistic framework for superoxide control of the stem cell niche and demonstrate how redox and DNA demethylation interact to define stem cell fate in plants.
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Developing single-atomic catalysts with superior selectivity and outstanding stability for CO2 electroreduction is desperately required but still challenging. Herein, confinement strategy and three-dimensional (3D) nanoporous structure design strategy are combined to construct unsaturated single Ni sites (Ni-N3) stabilized by pyridinic N-rich interconnected carbon nanosheets. The confinement agent chitosan and its strong interaction with g-C3N4 nanosheet are effective for dispersing Ni and restraining their agglomeration during pyrolysis, resulting in ultrastable Ni single-atom catalyst. Due to the confinement effect and structure advantage, such designed catalyst exhibits a nearly 100% selectivity and remarkable stability for CO2 electroreduction to CO, exceeding most reported state-of-the-art catalysts. Specifically, the CO Faradaic efficiency (FECO) maintains above 90% over a broad potential range (-0.55 to -0.95 V vs. RHE) and reaches a maximum value of 99.6% at a relatively low potential of -0.67 V. More importantly, the FECO is kept above 95% within a long-term 100 h electrolyzing. Density functional theory (DFT) calculations explain the high selectivity for CO generation is due to the high energy barrier required for hydrogen evolution on the unsaturated Ni-N3. This work provides a new designing strategy for the construction of ultrastable and highly selective single-atom catalysts for efficient CO2 conversion.
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The causative agent of coronavirus disease 2019 (COVID-19), known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread accumulatively to 240 countries and continues to evolve. To gain a comprehensive understanding of the epidemiological characteristics of imported variants in China and their correlation with global circulating variants, genomic surveillance data from 11 139 imported COVID-19 cases submitted by Chinese provincial CDC laboratories between 2021 and 2022 were analyzed. Consensus sequences underwent rigorous quality checks, followed by amino acid mutations analysis using Nextclade. Sequences with satisfactory quality control status were classified according to the Pango nomenclature. The results showed that the dominant variants in imported cases reflected the global epidemic trend. An increase in the number of imported SARS-CoV-2 lineages monitored in China in the second half of 2022, and the circulating Omicron subvariants changed from the ancestral lineages of BA.5 and BA.2 into the lineages containing key amino acid mutations of spike protein. There was significant variation in the detection of Omicron subvariants among continents (χ2 = 321.968, p < 0.001) in the second half of 2022, with four lineages (BA.2.3.7, BA.2.2, BA.5.2.7, and XBB.1.2) identified through imported surveillance mainly prevalent respectively in Taiwan, China, Hong Kong SAR, China, Russian Federation, and Singapore. These findings revealed the alterations in circulating imported variants from 2021 to 2022 in China, reflecting the higher diversity of lineages in the second half of 2022, and revealed the predominant lineages of countries or regions that are in close contacts to China, providing new insights into the global prevalence of SARS-CoV-2.
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COVID-19 , SARS-CoV-2 , Humanos , China/epidemiologia , COVID-19/epidemiologia , COVID-19/virologia , SARS-CoV-2/genética , SARS-CoV-2/classificação , Prevalência , Glicoproteína da Espícula de Coronavírus/genética , Filogenia , Mutação , Genoma Viral/genética , Variação GenéticaRESUMO
Mycosis fungoides (MF) is a low-grade malignant cutaneous T-cell lymphoma that originates from memory T cells. It typically follows a unique and relatively indolent disease course. MF is used to be characterized by a tissue-resident memory T cell (TRM) phenotype, although recent molecular research has revealed its complexity, casting doubt on the cell of origin and the TRM-MF paradigm. Recent clonal heterogeneity studies suggest that MF may originate from immature early precursor T cells. During development, the tumour microenvironment (TME) influences tumour cell phenotype. The exact origin and development trajectory of MF remains elusive. Clarifying the origin of MF cells is vital for accurate diagnosis and effective treatment.
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Micose Fungoide , Fenótipo , Neoplasias Cutâneas , Microambiente Tumoral , Micose Fungoide/patologia , Humanos , Neoplasias Cutâneas/patologia , Microambiente Tumoral/imunologia , Células T de Memória/imunologiaRESUMO
Rice straw is an agricultural waste, the disposal of which through open burning is an emerging challenge for ecology. Green manufacturing using straw returning provides a more avant-garde technique that is not only an effective management measure to improve soil fertility in agricultural ecosystems but also nurtures environmental stewardship by reducing waste and the carbon footprint. However, fresh straw that is returned to the field cannot be quickly decomposed, and screening microorganisms with the capacity to degrade straw and understanding their mechanism of action is an efficient approach to solve such problems. This study aimed to reveal the potential mechanism of influence exerted by exogenous degradative bacteria (ZJW-6) on the degradation of straw, growth of plants, and soil bacterial community during the process of returning rice straw to the soil. The inoculation with ZJW-6 enhanced the driving force of cellulose degradation. The acceleration of the rate of decomposition of straw releases nutrients that are easily absorbed by rice (Oryza sativa L.), providing favorable conditions for its growth and promoting its growth and development; prolongs the photosynthetic functioning period of leaves; and lays the material foundation for high yields of rice. ZJW-6 not only directly participates in cellulose degradation as degrading bacteria but also induces positive interactions between bacteria and fungi and enriches the microbial taxa that were related to straw degradation, enhancing the rate of rice straw degradation. Taken together, ZJW-6 has important biological potential and should be further studied, which will provide new insights and strategies for the appropriate treatment of rice straw. In the future, this degrading bacteria may provide a better opportunity to manage straw in an ecofriendly manner.
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Bactérias , Oryza , Microbiologia do Solo , Oryza/microbiologia , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Bactérias/metabolismo , Bactérias/crescimento & desenvolvimento , Caules de Planta/microbiologia , Caules de Planta/metabolismo , Celulose/metabolismo , Biodegradação Ambiental , Agricultura/métodos , Solo/químicaRESUMO
Aqueous zinc-ion batteries have received continuous interests because of applying low-cost and eco-friendly aqueous electrolytes and having high safety. Beyond energetically to explore new-type cathode materials, it is of great significance to regulate the zinc storage behavior of the existing cathodes in order to understand the underlying working mechanism. Therefore, as a proof of concept, this work achieves the regulation of zinc storage behaviors of the tunnel structure tunnel structure B-phase vanadium dioxide (VO2 (B)) and vanadium oxide (V6 O13 ) cathodes via a simple chemical tungsten-doping induction approach. Under low-concentration tungsten-doping induction of 1, 2 and 3 at.%, the tunnel sizes of VO2 (B) can be controlled readily. Moreover, the V6 O13 with large size tunnels can be achieved by medium-concentration tungsten induction of 6 and 9 at.%. It is demonstrated that tungsten induced VO2 (B) can achieve zinc storage without lattice structure change via operando X-ray diffraction analyses. Remarkably, via operando and non-operando analyses, tungsten induced V6 O13 with lager size tunnels can realize the oriented 1D zinc ion intercalation/deintercalation. The further kinetics analysis shows that the zinc storage is mainly diffusion control, which is different from most of vanadium-based cathodes with capacitance control. This viable tungsten-doping induction strategy provides a new insight into achieving the controllable regulation of zinc storage behaviors.
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Photovoltaic (PV) power generation is one of the world's most promising options for carbon emission reduction. However, whether the operation period of solar parks can increase greenhouse gas (GHG) emissions in hosting natural ecosystems has not been fully considered. Here, we conducted a field experiment to compensate for the lack of evaluation of the effects of PV array deployment on GHG emissions. Our results show that the PV arrays caused significant differences in air microclimate, soil properties, and vegetation characteristics. Simultaneously, PV arrays had more significant effects on CO2 and N2O emissions but a minor impact on CH4 uptake in the growing season. Of all the environmental variables included, soil temperature and moisture were the main drivers of GHG flux variation. The sustained flux global warming potential from the PV arrays significantly increased by 8.14% compared to the ambient grassland. Our evaluation models identified that the GHG footprint of PV arrays during the operation period on grasslands was 20.62 g CO2-eq kW h-1. Compared with our model estimates, GHG footprint estimates reported in previous studies were generally less by 25.46-50.76%. The contribution of PV power generation to GHG reduction may be overestimated without considering the impact of PV arrays on hosting ecosystems.
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Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Ecossistema , Dióxido de Carbono/análise , Metano/análise , Solo , Óxido Nitroso/análiseRESUMO
Aim: The purpose of this study was to evaluate whether tumor-educated platelet (TEP) snoRNAs could be used as a diagnostic biomarker for esophageal cancer (ESCA). Methods: Platelet precipitates were obtained from platelet-rich plasma by low-speed centrifugation, and total RNA was extracted from platelets using Trizol™ reagent. RT-qPCR was used to detect snoRNA expression, and the receiver operating characteristic was used to assess its diagnostic potential. Results: SNORA58, SNORA68 and SNORD93 were significantly upregulated in TEPs from ESCA patients and early-stage patients compared with healthy controls. Importantly, the three snoRNAs were capable of serving as circulating biomarkers of diagnostics and early diagnosis of ESCA, possessing areas under the curve of 0.846 and 0.857, respectively. Conclusion: TEP SNORA58, SNORA68 and SNORD93 could potentially serve as noninvasive biomarkers for diagnosis and early diagnosis of ESCA.
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Plaquetas , Neoplasias Esofágicas , Humanos , Biomarcadores Tumorais , Plaquetas/metabolismo , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , RNA Nuclear Pequeno/genéticaRESUMO
BACKGROUND: Evidence exists of a strong association between inflammation and a decrease in skeletal muscle function and bone mineral density (BMD); however, the specific mechanisms of these associations remain unclear. Adipokines, as key regulators of the inflammatory response, may be implicated in these processes. The objective of this study was to explore the potential correlation between adipokines, skeletal muscle function and BMD in middle-aged and elderly individuals. METHODS: A comparative cross-sectional study was carried out at the Huadong Hospital Affiliated with Fudan University (Shanghai, China). A total of 460 middle-aged and elderly individuals were recruited, and 125 were enrolled in the analysis. Their biochemical indices, body composition, skeletal muscle function and BMD were measured. Bioinformatic analysis was also employed to identify potential adipokine targets linked to skeletal muscle function and BMD. To validate these targets, plasma and peripheral blood mononuclear cells (PBMCs) were harvested from these individuals and subjected to western blotting (WB) and enzyme-linked immunosorbent assay (ELISA). RESULTS: Individuals in this cross-sectional study were categorized into 2 groups according to their median skeletal muscle mass (SMM) (28.8 kg for males and 20.6 kg for females). Individuals with lower SMM exhibited poorer grip strength (P = 0.017), longer 5-Times-Sit-to-Stand Test (FTSST) duration (P = 0.029), lower total hip BMD (P = 0.043), lower femoral neck BMD (P = 0.011) and higher levels of inflammatory markers in comparison with individuals with higher SMM. Bioinformatics analysis identified LEP, ADIPOQ, RBP4, and DPP4 as potential adipokine targets associated with skeletal muscle function and BMD. In vitro experiments demonstrated that individuals with decreased skeletal muscle function and BMD expressed higher levels of these adipokines. CONCLUSIONS: Skeletal muscle function is positively correlated with BMD and negatively correlated with levels of inflammatory markers among middle-aged and elderly individuals. Those with lower skeletal muscle function and BMD tend to have a higher expression of LEP, ADIPOQ, RBP4 and DPP4.
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Adipocinas , Densidade Óssea , Idoso , Masculino , Pessoa de Meia-Idade , Feminino , Humanos , Densidade Óssea/fisiologia , Estudos Transversais , Dipeptidil Peptidase 4 , Leucócitos Mononucleares , China , Músculo Esquelético/fisiologia , Absorciometria de Fóton , Proteínas Plasmáticas de Ligação ao RetinolRESUMO
Wheat sharp eyespot is a serious disease caused by the phytopathogens Rhizoctonia cerealis and R. solani. Some species in the genus Streptomyces have been identified as potential biocontrol agents against phytopathogens. In this investigation, the physiological, biochemical, phylogenetic, and genomic characteristics of strain HU2014 indicate that it is a novel Streptomyces sp. most closely related to Streptomyces albireticuli. Strain HU2014 exhibited strong antifungal activity against R. cerealis G11 and R. solani YL-3. Ultraperformance liquid chromatography-mass spectrometry on the four extracts from the extracellular filtrate of strain HU2014 identified 10 chemical constituents in the Natural Products Atlas with high match levels (more than 90%). In an antifungal efficiency test on wheat sharp eyespot, two extracts significantly reduced the lesion areas on bean leaves infected by R. solani YL-3. The drenching of wheat in pots with spore suspension of strain HU2014 demonstrated a control efficiency of 65.1% against R. cerealis G11 (compared with 66.9% when treated by a 30% hymexazol aqueous solution). Additionally, in vitro and pot experiments demonstrated that strain HU2014 can produce indoleacetic acid, siderophores, extracellular enzymes, and solubilized phosphate, and it can promote plant growth. We conclude that strain HU2014 could be a valuable microbial resource for growth promotion of wheat and biological control of wheat sharp eyespot.
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Rhizoctonia , Streptomyces , Rhizoctonia/fisiologia , Triticum/microbiologia , Antifúngicos , Filogenia , Doenças das Plantas/microbiologia , Extratos VegetaisRESUMO
Chitinases play a crucial role in insect metamorphosis by facilitating chitin degradation. Sarcophaga peregrina (Robineau-Desvoidy, 1830) (Diptera: Sarcophagidae) is a typical holometabolous insect and an important hygiene pest that causes myiasis in humans and other mammals and acts as a vector for various parasitic agents, including bacteria, viruses, and parasites. Enhancing the understanding of the metamorphosis in this species has significance for vector control. In this study, we identified a total of 12 chitinase genes in S. peregrina using bioinformatic analysis methods. Based on transcriptome data, SpIDGF2 and SpCht10 were selected for further functional investigation. The down-regulation of these genes by RNA interference led to developmental delays, disruptions in molting, and differences in cuticle composition during the pupal stage. These findings underscore the pivotal role of chitinase genes in the metamorphic process and offer valuable insights for effective control strategies.
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Quitinases , Dípteros , Sarcofagídeos , Humanos , Animais , Dípteros/genética , Sarcofagídeos/genética , Quitinases/genética , Metamorfose Biológica/genética , Transcriptoma , Mamíferos/genéticaRESUMO
Aim: The study aimed to clarify the diagnostic value of exosomal miRNAs in epithelial ovarian cancer (EOC). Methods: Plasma exosomes were isolated from peripheral blood of EOC patients and healthy donors by ultracentrifugation and verified by transmission electron microscopy, qNano and western blot. The expression of exosomal miRNAs was detected by quantitative PCR, and the diagnostic efficiency of exosomal miRNAs was evaluated by receiver operating characteristic analysis. Results: Exosomal miR-1260a, miR-7977 and miR-192-5p were significantly decreased in EOC as compared with healthy controls. The area under the curve of the combination of three exosomal miRNAs was 0.8337. Moreover, the level of exosomal miR-7977 was related to the neutrophil-lymphocyte ratio, which decreased in EOC patients with a high neutrophil-lymphocyte ratio. Conclusion: Exosomal miR-1260a, miR-7977 and miR-192-5p act as potentially EOC diagnostic and prognostic biomarkers.
This study aimed to identify some miRNAs that can act as predictive and diagnostic markers of ovarian cancer (OC). To do this, miRNAs were isolated from blood samples of OC patients and healthy donors. The level of miRNAs was tested, and the diagnostic value was analyzed using software. Three miRNAs were identified that could be predictive of OC and OC outcome.
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Exossomos , MicroRNAs , Neoplasias Ovarianas , Feminino , Humanos , Biomarcadores Tumorais , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/metabolismo , Exossomos/genética , Exossomos/metabolismo , MicroRNAs/metabolismo , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genéticaRESUMO
BACKGROUND: Non-small-cell lung cancer (NSCLC) still occupied the leading reason of cancer death due to lack of availability of early detection. This study aimed to identify the effective biomarkers for the early-stage NSCLC diagnostics based on plasma snoRNAs. MATERIALS AND METHODS: The differential snoRNAs between lung cancer patients and healthy donors were analyzed using the SNORic and TCGA databases. SNORD42B and SNORD111 were screened out and further verified in 48 FFPE NSCLC and adjacent normal tissues, as well as in plasma from 165 NSCLC patients and 118 health donors using qRT-PCR. Next, their diagnostic efficiency, as well as combined with carcinoembryonic antigen (CEA), was obtained by the analysis of receiver operating characteristic (ROC). RESULTS: We first screened out 47 top differential snoRNAs, among which the top 10 upregulated snoRNAs in LUAD were U44, U75, U78, U77, SNORD72, SNORD13, SNORD12B, SCARNA5, U80, SNORD41, and in LUSC were U44, U75, U78, SNORD41, SNORD111, SNORA56, U17a, SNORD35A, SNORD32A, SNORA71D. SNORD42B and SNORD111 was significantly increased not only in tumor tissues but also in plasma from NSCLC and early-stage NSCLC patients. They were capable to act as promising biomarkers for NSCLC and early-stage NSCLC diagnosis. Moreover, CEA diagnostic efficiency for early-stage NSCLC was significantly improved when combined with these two plasma snoRNAs. CONCLUSION: SNORD42B and SNORD111 could act as the potential and non-invasive diagnostic biomarkers for NSCLC and early-stage NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Biomarcadores Tumorais/genética , Antígeno Carcinoembrionário , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Detecção Precoce de Câncer , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , RNA Nuclear Pequeno/genéticaRESUMO
BACKGROUND: Quality is the most important factor in satisfaction. However, the existing satisfaction index model of urban and rural resident-based basic medical insurance scheme (SIM_URRBMI) lacks the segmentation of perceived quality elements, it couldn't provide a reference for quality improvement and satisfaction promotion. This study aims to construct a revised SIM_URRBMI that can accurately and detailly measure perceived quality and provide feasible and scientific suggestions for improving the satisfaction of urban and rural residents' basic medical insurance scheme (URRBMI) in China. METHODS: Based on the theoretical framework of the American Customer Satisfaction Index, the elements of perceived quality were refined through literature review and expert consultation, and a pool of alternative measurement variables was formed. A three-stage randomized stratified cluster sampling was adopted. The main decision makers of URRBMI in the families of primary school students in 8 primary schools in Changsha were selected. Both the classic test theory and the item response theory were used for measurement variables selection. The reliability and validity of the model were tested by partial least squares (PLS)-related methods. RESULTS: A total of 1909 respondents who had URRBMI for their children were investigated. The SIM_URRBMI1.0 consists of 11 latent variables and 28 measurement variables with good reliability and validity. Among the three explanatory variables of public satisfaction, perceived quality had the largest total effect (path coefficient) (0.737). The variable with the greatest effect among the five first-order latent variables on perceived quality was the quality of the medical insurance policy (0.472). CONCLUSIONS: The SIM_URRBMI1.0 consists of 28 measurement variables and 11 latent variables. It is a reliable, valid, and standard satisfaction measurement tool for URRBMI with good prediction ability for public satisfaction. In addition, the model provides an accurate evaluation of the perceived quality, which will greatly help with performance improvement diagnosis. The most critical aspects of satisfaction improvement are optimizing the scope and proportion of reimbursement as well as setting appropriate level of deductible and capitation of URRBMI.
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Seguro Saúde , Satisfação Pessoal , Criança , China , Humanos , Reprodutibilidade dos Testes , População RuralRESUMO
To suppress the electron-hole recombination and enhance the electron transfer on carbon nitride, an Fe-doped porous carbon nitride catalyst (Fe/SCN) was synthesized via supramolecular self-assembly method and applied in heterogeneous Fenton activation for efficient tetracycline (TC) degradation. Various characterizations revealed that the catalyst exhibited excellent visible light capture performance and electron transfer capacity. The highest degradation efficiency and mineralization rate of TC (10 mg L-1) were achieved under neutral condition (90.3% and 61.2%, respectively) with the leaching of Fe less than 14 µg L-1. Free radical quenching experiments and spin-resonance spectroscopy characterizations revealed the dominating role of OH in TC degradation, and density functional theory calculation confirmed the formation of Fe-NX and revealed the interaction between Fe sites and H2O2. Three possible pathways of TC degradation were proposed, and the biological inhibition test revealed the potential of Fe/SCN/H2O2 system to reduce environmental risks caused by TC. This work provides a new insight into the design of metal-doped heterogeneous Fenton catalyst for the efficient degradation of antibiotic contaminants in water.
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Peróxido de Hidrogênio , Tetraciclina , Antibacterianos , Catálise , Peróxido de Hidrogênio/química , LuzRESUMO
OBJECTIVES: Stroke readmission increases financial burden on the family and the consumption of medical resources, and 30-day readmission rate is an important indicator for quality evaluation on health services. The influential factors for readmission mainly include patient-related factors, hospital factors, and society-related factors, with regional differences. This study aims to explore the spatial distribution and its main relevant factors for 30-day readmission of stroke patients in Hunan Province, and to provide the useful information for the improvement of regional prevention and control of stroke readmission. METHODS: Stroke patients in Hunan Province who were hospitalized in 2018 and readmitted within 30 days were included in the study. The vector map of the county boundary in Hunan Province was used as the basic map since county was the spatial analysis unit. SPSS 26.0 and ArcGIS 10.8 were used for statistical analysis that contains descriptive analysis of the general situation and the distribution map of readmission rate within 30 days of stroke patients. Spatial autocorrelation analysis and spatial regression analysis were further used to find the spatial clusters of the 30-day readmission rate of stroke and the local relationship between the readmission rate and main influential factors. RESULTS: In 2018, a total of 172 800 stroke patients were hospitalized in Hunan Province, of which 6 953 patients were re-hospitalized within 30 days after discharging due to stroke. The 30-day readmission rate was 4.09% in Hunan Province. The clusters of stroke readmission rates were mainly concentrated in the northeast and western regions in Hunan Province. The geographically weighted regression revealed that proportion of patients with complications, number of hospitals per 10 000 population and number of primary medical and health care institution per 10 000 population were the main relevant factors for stroke readmission, and there were differences both in the direction and degree of the effect on readmission in different regions. CONCLUSIONS: The 30-day readmission rate for stroke patients in Hunan province and its main influential factors had spatial heterogeneity. The key prevention and control areas were mainly concentrated in the northeast and western regions. It is recommended that the prevention and treatment of stroke complications and the construction of medical institutions need to be strengthened to improve the quality of medical services, particularly in the western region. The importance to the treatment of stroke complications should be attached in the northern region, and the primary health care should be reinforced in the northeast region. All counties should take prevention and control measures according to local conditions, so as to effectively control the readmission rate of stroke within 30 days.
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Readmissão do Paciente , Acidente Vascular Cerebral , China/epidemiologia , Humanos , Análise Espacial , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapiaRESUMO
BACKGROUND: Nitrogen (N) deficiency is a major constraint for plant production in many areas. Developing the new crop genotypes with high productivity under N deficiency is an important approach to maintain agricultural production. Therefore, understanding how plant response to N deficiency and the mechanism of N-deficiency tolerance are very important for sustainable development of modern crop production. RESULTS: In this study, the physiological responses and fatty acid composition were investigated in 24 wheat cultivars under N-deficient stress. Through Pearson's correlation analysis and principal component analysis, the responses of 24 wheat cultivars were evaluated. The results showed that the plant growth and carbohydrate metabolism were all differently affected by N deficiency in all tested wheat cultivars. The seedlings that had high shoot biomass also maintained high level of chlorophyll content under N deficiency. Moreover, the changes in fatty acid composition, especially the linolenic acid (18:3) and the double bond index (DBI), showed close positive correlations with the shoot dry weight and chlorophyll content alterations in response to N-deficient condition. These results indicated that beside the chlorophyll content, the linolenic acid content and DBI may also contribute to N-deficiency adaptation, thus could be considered as efficient indicators for evaluation of different response in wheat seedlings under N-deficient condition. CONCLUSIONS: The alteration in fatty acid composition can potentially contribute to N-deficiency tolerance in plants, and the regulation of fatty acid compositions maybe an effective strategy for plants to adapt to N-deficient stress.
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Nitrogênio/deficiência , Plântula/fisiologia , Triticum/fisiologia , Ácido alfa-Linolênico/fisiologia , Ácidos Graxos/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Estresse Fisiológico , Triticum/crescimento & desenvolvimento , Ácido alfa-Linolênico/metabolismoRESUMO
BACKGROUND: Water deficiency is likely to become more frequent and intense as a result of global climate change, which may severely impact agricultural production in the world. The positive effects of melatonin (MEL) on alleviation drought or osmotic stress-induced water deficiency in plants has been well reported. However, the underlying mechanism of MEL on the detailed process of plant water uptake and transport under water deficiency condition remains largely unknown. RESULTS: Application of 1 µM MEL led to enhanced tolerance to water deficiency stress in maize seedlings, as evidenced by maintaining the higher photosynthetic parameters, leaf water status and plant transpiration rate. The relatively higher whole-plant hydraulic conductance (Kplant) and root hydraulic conductance (Lpr) in MEL-treated seedlings suggest that exogenous MEL alleviated water deficiency stress by promoting root water absorption. HgCl2 (aquaporin inhibitor) treatment inhibit the transpiration rate in MEL-treated plants greater than those of MEL-untreated; after recovery by dithiothreitol (DTT, anti-inhibitor), the transpiration rate in MEL-treated plants increased much higher than those of untreated plants. Moreover, under water deficiency, the transcription level of aquaporin genes was up-regulated by MEL application, and the H2O2 was less accumulated in MEL-treated root. CONCLUSIONS: Exogenous MEL promoted aquaporin activity, which contributed to the maintaining of Lpr and Kplant under short-term water deficiency. The increased water uptake and transport lead to improved water status and thus increased tolerance to PEG-induced short-term water deficiency in maize seedlings.
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Melatonina/farmacologia , Transpiração Vegetal , Polietilenoglicóis/administração & dosagem , Água/metabolismo , Zea mays/fisiologia , Zea mays/efeitos dos fármacosRESUMO
Protein neddylation, a process of conjugating neural precursor cell expressed, developmentally downregulated 8 (NEDD8) to substrates, plays a tumor-promoting role in lung carcinogenesis. Our previous study showed MLN4924, an inhibitor of NEDD8 activating enzyme (E1), significantly inhibits the growth of multiple cancer cells. However, resistance can develop to MLN4924 by mutation. Therefore, it is important to further understand how NEDD8 acts in lung cancer. In the present study, we demonstrated NEDD8 is overactivated in lung cancers and confers a worse patient overall survival. Furthermore, we report that in lung adenocarcinoma cells, NEDD8 depletion significantly suppressed lung cancer cell growth and progression both in vitro and in vivo. Mechanistic studies revealed that NEDD8 depletion induced the accumulation of a panel of tumor-suppressive cullin-RING ubiquitin ligase substrates (e.g., p21, p27, and Wee1) via blocking their degradation, triggering cell cycle arrest at G2 phase, thus inducing apoptosis or senescence in a cell-line-dependent manner. The present study demonstrates the role of NEDD8 in regulating the malignant phenotypes of lung cancer cells and further validates NEDD8 as a potential therapeutic target in lung cancer.
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Adenocarcinoma de Pulmão/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Proteína NEDD8/metabolismo , Adenocarcinoma de Pulmão/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclopentanos/farmacologia , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ubiquitina/metabolismoRESUMO
A 3D porous graphene composite film containing Ni/NiO hybrid nanoparticles (Ni/NiO NPs) is prepared by combining electrophoresis deposition and thermal H2 annealing techniques. The Ni/NiO NPs with a mean diameter of 45 nm are uniformly embedded on both the exterior and interior surfaces of reduced graphene, forming a 3D porous reduced graphene oxide composite film (Ni/NiO rGO). The insertion of Ni/NiO NPs into rGO greatly improves the electric conductivity and charge storage capability of the resultant Ni/NiO rGO film. By directly using it as freestanding electrodes, the fabricated lithium-ion battery and supercapacitor respectively exhibited high capacities of 758 mAh g-1@ 0.2 A g-1 and 430.8 F g-1@0.5 A g-1, an increase of 82.3-fold and 20.2-fold compared to the pure rGO electrode-based counterparts under the same condition.