RESUMEN
Heading date (or flowering time) is a key agronomic trait that affects seasonal and regional adaption of rice cultivars. An unoptimized heading date can either not achieve a high yield or has a high risk of encountering abiotic stresses. There is a strong demand on the mild to moderate adjusting the heading date in breeding practice. Genome editing is a promising method which allows more precise and faster changing the heading date of rice. However, direct knock out of major genes involved in regulating heading date will not always achieve a new germplasm with expected heading date. It is still challenging to quantitatively adjust the heading date of elite cultivars with best adaption for broader region. In this study, we used a CRISPR-Cas9 based genome editing strategy called high-efficiency multiplex promoter-targeting (HMP) to generate novel alleles at cis-regulatory regions of three major heading date genes: Hd1, Ghd7 and DTH8. We achieved a series of germplasm with quantitative variations of heading date by editing promoter regions and adjusting the expression levels of these genes. We performed field trials to screen for the best adapted lines for different regions. We successfully expanded an elite cultivar Ningjing8 (NJ8) to a higher latitude region by selecting a line with a mild early heading phenotype that escaped from cold stress and achieved high yield potential. Our study demonstrates that HMP is a powerful tool for quantitatively regulating rice heading date and expanding elite cultivars to broader regions.
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Oryza , Oryza/metabolismo , Sitios de Carácter Cuantitativo , Sistemas CRISPR-Cas/genética , Fitomejoramiento , Regiones Promotoras Genéticas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genéticaRESUMEN
Coping with the critical challenge of imidacloprid (IMI) contamination in sewage treatment and farmland drainage purification, this study presents a pioneering development of an advanced modified graphitic white melon seed shells biochar (Fe/Zn@WBC). The Fe/Zn@WBC demonstrates a substantial enhancement in adsorption efficiency for IMI, achieving a remarkable removal rate of 87.69% within 30 min and a significantly higher initial adsorption rate parameter h = 4.176 mg g-1·min-1. This significant improvement outperforms WBC (12.22%, h = 0.115 mg g-1·min-1) and highlights the influence of optimized adsorption conditions at 900 °C and the graphitization degree resulting from Fe/Zn bimetallic oxide modification. Characterization analysis and batch sorption experiments including kinetics, isotherms, thermodynamics and pH factors illustrate that chemical adsorption is the main type of adsorption mechanism responsible for this superior ability to remove IMI through pore filling, hydrogen bonding, hydrophobic interaction, electrostatics interaction, π-π interactions as well as complexation processes. Furthermore, we demonstrate exceptional stability of Fe/Zn@WBC across a broad pH range (pH = 3-11), co-existing ions presence along with humic acid under various real water conditions while maintaining high removal efficiency. This study presents an advanced biochar adsorbent, Fe/Zn@WBC, with efficient adsorption capacity and easy preparation. Through three regeneration cycles via pyrolysis method, it demonstrates excellent pyrolysis regeneration capabilities with an average removal efficiency of 92.02%. The magnetic properties enable rapid separation facilitated by magnetic analysis. By elucidating the efficacy and mechanistic foundations of Fe/Zn@WBC, this research significantly contributes to the field of environmental remediation by providing a scalable solution for IMI removal and enhancing scientific understanding of bimetallic oxides-hydrophilic organic pollutant interactions.
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Carbón Orgánico , Grafito , Neonicotinoides , Nitrocompuestos , Contaminantes Químicos del Agua , Zinc , Neonicotinoides/química , Carbón Orgánico/química , Grafito/química , Contaminantes Químicos del Agua/química , Adsorción , Zinc/química , Nitrocompuestos/química , Hierro/química , Insecticidas/química , Óxidos/químicaRESUMEN
At present, biochar has a large application potential in soil amelioration, pollution remediation, carbon sequestration and emission reduction, and research on the effect of biochar on soil ecology and environment has made positive progress. However, under natural and anthropogenic perturbations, biochar may undergo a series of environmental behaviors such as migratory transformation, mineralization and decomposition, and synergistic transport, thus posing certain potential risks. This paper outlines the multi-interfacial migration pathway of biochar in "air-soil-plant-animal-water", and analyzes the migration process and mechanism at different interfaces during the preparation, transportation and application of biochar. The two stages of the biochar mineralization process (mineralization of easily degradable aliphatic carbon components in the early stage and mineralization of relatively stable aromatic carbon components in the later stage) were described, the self-influencing factors and external environmental factors of biochar mineralization were analyzed, and the mineral stabilization mechanism and positive/negative excitation effects of biochar into the soil were elucidated. The proximity between field natural and artificially simulated aging of biochar were analyzed, and the change of its properties showed a trend of biological aging > chemical aging > physical aging > natural aging, and in order to improve the simulation and prediction, the artificially simulated aging party needs to be changed from a qualitative method to a quantitative method. The technical advantages, application scope and potential drawbacks of different biochar modification methods were compared, and biological modification can create new materials with enhanced environmental application. The stability performance of modified biochar was compared, indicating that raw materials, pyrolysis temperature and modification method were the key factors affecting the stability of biochar. The potential risks to the soil environment from different pollutants carried by biochar were summarized, the levels of pollutants released from biochar in the soil environment were highlighted, and a comprehensive selection of ecological risk assessment methods was suggested in terms of evaluation requirements, data acquisition and operation difficulty. Dynamic tracing of migration decomposition behavior, long-term assessment of pollution remediation effects, and directional design of modified composite biochar materials were proposed as scientific issues worthy of focused attention. The results can provide a certain reference basis for the theoretical research and technological development of biochar.
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Carbón Orgánico , Ecosistema , Suelo , Carbón Orgánico/química , Suelo/química , Medición de Riesgo , Contaminantes del Suelo , EcologíaRESUMEN
BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a malignancy characterized by challenging early diagnosis and poor prognosis. It is believed that coagulation has an impact on the tumor microenvironment of PDAC. The aim of this study is to further distinguish coagulation-related genes and investigate immune infiltration in PDAC. METHODS: We gathered two subtypes of coagulation-related genes from the KEGG database, and acquired transcriptome sequencing data and clinical information on PDAC from The Cancer Genome Atlas (TCGA) database. Using an unsupervised clustering method, we categorized patients into distinct clusters. We investigated the mutation frequency to explore genomic features and performed enrichment analysis, utilizing Gene Ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) to explore pathways. CIBERSORT was used to analyze the relationship between tumor immune infiltration and the two clusters. A prognostic model was created for risk stratification, and a nomogram was established to assist in determining the risk score. The response to immunotherapy was assessed using the IMvigor210 cohort. Finally, PDAC patients were recruited, and experimental samples were collected to validate the infiltration of neutrophils using immunohistochemistry. In addition, and identify the ITGA2 expression and function were identified by analyzing single cell sequencing data. RESULTS: Two coagulation-related clusters were established based on the coagulation pathways present in PDAC patients. Functional enrichment analysis revealed different pathways in the two clusters. Approximately 49.4% of PDAC patients experienced DNA mutation in coagulation-related genes. Patients in the two clusters displayed significant differences in terms of immune cell infiltration, immune checkpoint, tumor microenvironment and TMB. We developed a 4-gene prognostic stratified model through LASSO analysis. Based on the risk score, the nomogram can accurately predict the prognosis in PDAC patients. We identified ITGA2 as a hub gene, which linked to poor overall survival (OS) and short disease-free survival (DFS). Single-cell sequencing analysis demonstrated that ITGA2 was expressed by ductal cells in PDAC. CONCLUSIONS: Our study demonstrated the correlation between coagulation-related genes and the tumor immune microenvironment. The stratified model can predict the prognosis and calculate the benefits of drug therapy, thus providing the recommendations for clinical personalized treatment.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Microambiente Tumoral/genética , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/genética , Pronóstico , Neoplasias PancreáticasRESUMEN
Bioaccumulation factor (BAF) of pollutants is an important parameter for evaluating their bioaccumulation potential and an important indicator for evaluating their environmental risks. However, little study exits on the BAF of novel brominated flame retardants (NBFRs). The present study determined 17 NBFRs in 24 water samples in dissolved phase and 93 crucian carp samples collected from an electronic waste recycling site in northern China, in order to examine their contamination, distribution and bioaccumulation. The results showed that the targeted NBFRs were widely detectable in the dissolved phase and crucian carps. In dissolved phase, allyl 2,4,6-tribromophenyl ether (ATE) had the highest detectable rate (100%) and concentration (mean: 1.3 ± 0.62 ng/L), but in crucian carp, hexachlorocyclopentenyl-dibromocyclooctane (HCDBCO) was the one with the highest detectable rate (89%) and concentration (mean: 16 ± 9.2 ng/g wet weight (ww)) among all 17 NBFRs. The discharge and water solubility of NBFRs determined their concentration in the dissolved phase, while the concentration of NBFRs in crucian carp was the results of their discharge and food exposure. The estimated BAFs exceeded 5000 L/kg for petabromoethylbenzene (PBEB), pentabromotoluene (PBT), HCDBCO, pentabromobenzyl acrylate (PBBA), 1,2,3,4,5-pentabromobenzene (PBBZ), 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), hexabromobenzene (HBBZ), and α-1,2,5,6-tetrabromocyclooctane (α-TBCO), suggesting that these compounds were above the hazard standard of bioaccumulation. Although the BAFs of 2,3,5,6-tetrabromo-p-xylene (p-TBX), 1,2-bis(2,4,6-tribromophenoxy)-ethane (BTBPE), α-/ß-tetrabromoethylcyclohexane (α-/ß-TBECH) and ATE were less than 5000, the potential of bioaccumulation cannot be ignored. The log BAF of tested NBFRs showed a pattern of first increasing and then decreasing with the increase of log KOW, the water solubility of NBFRs, the exposure to fish, the uptake and depuration of fish were the key factor to this pattern. To our knowledge, the BAF values of the most of NBFRs calculated in this study were not reported in the published work previously.
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Carpas , Residuos Electrónicos , Retardadores de Llama , Animales , Carpa Dorada , Retardadores de Llama/análisis , Bioacumulación , Monitoreo del Ambiente/métodos , Éteres Difenilos Halogenados/análisis , AguaRESUMEN
Extensive application of neonicotinoid insecticides (NNIs) in agricultural production has resulted in widespread contamination of multiple environmental media. To investigate the occurrence and fate of NNIs in the largest marsh distribution area in Northeast China, an integrated ecosystem covering farmlands, rivers, and marshes, referred to as the farmland-river-marsh continuum in this study, was chosen for soil, water, and sediment sampling. Five NNIs were detected, with imidacloprid (IMI), thiamethoxam (THM), and clothianidin (CLO) being the most frequently detected ones in different samples. Concentrations of target NNIs in soil, surface water, and sediment samples were 2.23-136 ng/g dry weight (dw), 3.20-51.7 ng/L, and 1.53-8.40 ng/g dw, respectively. In soils, NNIs were detected more often and at higher concentrations in upland fields, while the concentration of NNIs in the soybean-growing soils (71.5 ng/g dw) was significantly higher than in the rice-growing soils (18.5 ng/g dw) (p < 0.05). Total concentration of NNIs in surface water was lower in the Qixing River channel than inside the marsh, while that in sediments showed an opposite trend. Total migration mass of IMI from approximately 157,000 ha of farmland soil by surface runoff was estimated to be 2636-3402 kg from the application time to the sampling period. The storage of NNIs in sediments was estimated to range from 45.9 to 252 ng/cm2. The estimated environmental risks, calculated as the risk quotients (RQs), revealed low risks to aquatic organisms (RQs <0.1) from the residual concentrations of NNIs in water.
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Insecticidas , Contaminantes Químicos del Agua , Insecticidas/análisis , Humedales , Ecosistema , Neonicotinoides/análisis , Agua , Suelo , China , Contaminantes Químicos del Agua/análisisRESUMEN
The endosomal sorting complex required for transport (ESCRT) is highly conserved in eukaryotic cells and plays an essential role in the biogenesis of multivesicular bodies and cargo degradation to the plant vacuole or lysosomes. Although ESCRT components affect a variety of plant growth and development processes, their impact on leaf development is rarely reported. Here, we found that OsSNF7.2, an ESCRT-III component, controls leaf rolling in rice (Oryza sativa). The Ossnf7.2 mutant rolled leaf 17 (rl17) has adaxially rolled leaves due to the decreased number and size of the bulliform cells. OsSNF7.2 is expressed ubiquitously in all tissues, and its protein is localized in the endosomal compartments. OsSNF7.2 homologs, including OsSNF7, OsSNF7.3, and OsSNF7.4, can physically interact with OsSNF7.2, but their single mutation did not result in leaf rolling. Other ESCRT complex subunits, namely OsVPS20, OsVPS24, and OsBRO1, also interact with OsSNF7.2. Further assays revealed that OsSNF7.2 interacts with OsYUC8 and aids its vacuolar degradation. Both Osyuc8 and rl17 Osyuc8 showed rolled leaves, indicating that OsYUC8 and OsSNF7.2 function in the same pathway, conferring leaf development. This study reveals a new biological function for the ESCRT-III components, and provides new insights into the molecular mechanisms underlying leaf rolling.
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Complejos de Clasificación Endosomal Requeridos para el Transporte , Oryza , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Endosomas/metabolismo , Hojas de la Planta/metabolismo , Transporte de Proteínas/genéticaRESUMEN
Rice is a facultative short day (SD) plant. In addition to serving as a model plant for molecular genetic studies of monocots, rice is a staple crop for about half of the world's population. Heading date is a critical agronomic trait, and many genes controlling heading date have been cloned over the last 2 decades. The mechanism of flowering in rice from recognition of day length by leaves to floral activation in the shoot apical meristem has been extensively studied. In this review, we summarise current progress on transcriptional and post-transcriptional regulation of heading date in rice, with emphasis on post-translational modifications of key regulators, including Heading date 1 (Hd1), Early heading date 1 (Ehd1), Grain number, plant height, and heading date7 (Ghd7). The contribution of heading date genes to heterosis and the expansion of rice cultivation areas from low-latitude to high-latitude regions are also discussed. To overcome the limitations of diverse genetic backgrounds used in heading date studies and to gain a clearer understanding of flowering in rice, we propose a systematic collection of genetic resources in a common genetic background. Strategies in breeding adapted cultivars by rational design are also discussed.
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Oryza , Flores/genética , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Oryza/metabolismo , Fotoperiodo , Fitomejoramiento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Methyl siloxanes are identified as emerging persistent toxic compounds and the ecological environment risks of these compounds have been caused of great concern worldwide. In this study, the concentrations of methyl siloxanes were reported in dissolved water and crucian carp around a methyl siloxane production factory located in Liaoning Province, Northeast China. D4, D5, D6, D7, L4, L5 and L6 were detectable both in dissolved water and crucian carp. The total concentrations of 7 methyl siloxanes (Σ7MS) were 14 ± 6.3 ng/L in dissolved water and 43 ± 22 ng/g ww in crucian carp, respectively. D5 has the highest concentration both in dissolved water (5.5 ± 3.5 ng/L) and crucian carp (17 ± 11 ng/g ww). Based on the monitoring values, bioaccumulation factor (BAF) of these compounds were calculated. Significant bioaccumulation potential was observed for D4 (BAF = 5900 ± 3500 L/kg) based on the bioaccumulation criteria suggested by USEPA and EU (BAF > 5000 L/kg). To our understanding, this is the first report of BAF values of methyl siloxane in field study, which will provide important support for further assessment of bioaccumulation of these compounds.
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Carpas/metabolismo , Siloxanos/análisis , Siloxanos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Bioacumulación , China , Monitoreo del Ambiente , Carpa Dorada/metabolismo , Contaminantes Químicos del Agua/análisisRESUMEN
Flood disasters are sudden, frequent, uncertain and highly hazardous natural disasters. The precise identification of the spatiotemporal evolution characteristics, key driving factors and influencing mechanisms of resilience has become a hot spot in disaster risk reduction research. Therefore, the cumulative information contribution rate-Pearson correlation coefficient (CICR- PCC) model is used in this paper to construct a flood disaster resilience index system by quantitative methods, and a support vector regression model refined by the selfish herd optimizer with elite opposition-based learning (EO-SHO-SVR) is built to improve the accuracy of flood disaster resilience evaluation. On this basis, the EO-SHO-SVR model is used to analyze the spatiotemporal evolution of flood disaster resilience in the Jiansanjiang branch of China Beidahuang Agricultural Reclamation Group Co., Ltd. over the past 22 years. In addition, to verify the comprehensive performance of the EO-SHO-SVR model, support vector regression (SVR), imperial competition algorithm-improved support vector regression (ICA-SVR), and unimproved selfish herd optimizer support vector regression (SHO-SVR) models were selected for comparative analysis. The results show that during the study period, the resilience levels reached a plateau of high levels from 1997 to 2018 after experiencing a state of steady low levels followed by increased volatility. Among the investigated factors, land-average flood prevention investment, GDP per capita, agricultural machinery power per unit of arable land, water conservancy project investment as a percentage of GDP, and rainfall are the main driving factors that cause spatiotemporal differences in flood disaster resilience in the study area. Spatially, the resilience levels in the Jiansanjiang branch are ordered as northern farms > southern farms > central farms, and the comprehensive index of resilience shows an increasing trend from west to east. In the model comparison, the EO-SHO-SVR model has outstanding advantages in fitting performance, reliability, rationality and stability, which fully demonstrates that the EO-SHO-SVR model is highly advanced and practical in the measurement of flood disaster resilience. These research results can provide a more accurate evaluation model of regional flood disaster resilience. In addition, they can also provide valuable information for regional flood resilience improvement and flood risk avoidance.
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Desastres , Inundaciones , Algoritmos , China , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Although advanced non-squamous non-small cell lung cancer (NSCLC) patients have significantly better survival outcomes after pemetrexed based treatment, a subset of patients still show intrinsic resistance and progress rapidly. Therefore we aimed to use a blood-based protein signature (VeriStrat, VS) to analyze whether VS could identify the subset of patients who had poor efficacy on pemetrexed therapy. METHODS: This study retrospectively analysed 72 advanced lung adenocarcinoma patients who received first-line pemetrexed/platinum or combined with bevacizumab treatment. RESULTS: Plasma samples from these patients were analysed using VS and classified into the Good (VS-G) or Poor (VS-P) group. The relationship between efficacy and VS status was further investigated. Of the 72 patients included in this study, 35 (48.6%) were treated with pemetrexed plus platinum and 37 (51.4%) were treated with pemetrexed/platinum combined with bevacizumab. Among all patients, 60 (83.3%) and 12 (16.7%) patients were classified as VS-G and VS-P, respectively. VS-G patients had significantly better median progression-free survival (PFS) (Unreached vs. 4.2 months; P < 0.001) than VS-P patients. In addition, the partial response (PR) rate was higher in the VS-G group than that in the VS-P group (46.7% vs. 25.0%, P = 0.212). Subgroup analysis showed that PFS was also significantly longer in the VS-G group than that in the VS-P group regardless of whether patients received chemotherapy alone or chemotherapy plus bevacizumab. CONCLUSIONS: Our study indicated that VS might be considered as a novel and valid method to predict the efficacy of pemetrexed-based therapy and identify a subset of advanced lung adenocarcinoma patients who had intrinsic resistance to pemetrexed based regimens. However, larger sample studies are still needed to further confirm this result.
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Accurately predicting and testing the types of Pulmonary arterial hypertension (PAH) of each patient using cost-effective microarray-based expression data and machine learning algorithms could greatly help either identifying the most targeting medicine or adopting other therapeutic measures that could correct/restore defective genetic signaling at the early stage. Furthermore, the prediction model construction processes can also help identifying highly informative genes controlling PAH, leading to enhanced understanding of the disease etiology and molecular pathways. In this study, we used several different gene filtering methods based on microarray expression data obtained from a high-quality patient PAH dataset. Following that, we proposed a novel feature selection and refinement algorithm in conjunction with well-known machine learning methods to identify a small set of highly informative genes. Results indicated that clusters of small-expression genes could be extremely informative at predicting and differentiating different forms of PAH. Additionally, our proposed novel feature refinement algorithm could lead to significant enhancement in model performance. To summarize, integrated with state-of-the-art machine learning and novel feature refining algorithms, the most accurate models could provide near-perfect classification accuracies using very few (close to ten) low-expression genes.
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Hipertensión Arterial Pulmonar/genética , Algoritmos , Estudios de Casos y Controles , Biología Computacional , Bases de Datos Genéticas , Expresión Génica , Perfilación de la Expresión Génica/estadística & datos numéricos , Humanos , Modelos Genéticos , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos/estadística & datos numéricos , Hipertensión Arterial Pulmonar/clasificación , Hipertensión Arterial Pulmonar/etiología , Aprendizaje Automático SupervisadoRESUMEN
In the past decade, the application of biochar in agricultural soils has attracted wide attention. However, few studies have carefully explored the effects of biochar modification on plant leaf nutrients and the physiological process of plant leaves. To provide a better growing environment for crops and explore the best regulation mode of biochar in the farmland soil environment in the typical black loam area of Heilongjiang Province, through field experiments, we selected soybeans as the test crop and applied biochar in the soil. The agronomic characteristics and soil conditions of soybean plants were monitored by stage. The effects of different application methods and biochar gradients on the water and heat changes in soil tillage layers during different growth stages of crops were discussed, and the subtle differences of agronomic characteristics in different growth stages of crops were compared. The results showed that all kinds of biochar application modes could not change the general trend of water and heat change in soil tillage layer affected by environmental factors, and the effect of biochar application on soil liquid moisture content at 20 cm soil layer was not obvious. Biochar application can increase plant height and reduce stem diameter, but the effect is non-linear. The leaf nitrogen content (Leaf N-content) and leaf chlorophyll relative content (SPAD) were vertically distributed in the canopy, but they did not change significantly with the change of biochar application rate and mode. The application of biochar in autumn may bring crops into maturity earlier. Under the biochar application rate of 9 kg m-2, the mixed application in spring and autumn can bring the best biochar application effect.
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Glycine max , Suelo , Carbón Orgánico , Estaciones del Año , TemperaturaRESUMEN
Rice (Oryza sativa) is a facultative short-day (SD) plant, flowering early under SD and late under long-day (LD) conditions. Ghd7 is a major regulator of flowering time in rice, which strongly delays flowering under LD. Induction of Ghd7 expression by phytochromes has been shown to contribute to photoperiodic regulation of flowering in rice. Here, we show that Ghd7 also is regulated by phytochromes at a post-transcriptional level. We found that constitutive expression of Ghd7 delays flowering in the wild-type (WT) background, but not in the se5 mutant background (deficient in functional phytochromes) under LD and that Ghd7 protein fails to accumulate in the se5 mutant. We also found that co-expressing OsGIGANTEA (OsGI) with Ghd7 causes reduced accumulation of Ghd7 protein and partially suppresses the delayed flowering phenotype in the WT background, suggesting that phytochromes and OsGI play antagonist roles in regulating Ghd7 protein stability and flowering time. We show that OsPHYA, OsPHYB and OsGI could directly interact with Ghd7. Interestingly, OsPHYA and OsPHYB could inhibit the interaction between OsGI and Ghd7, thus helping to stabilize Ghd7 protein. Our results revealed a new level of Ghd7 regulation by phytochromes and OsGI in photoperiodic control of flowering in rice.
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Flores/fisiología , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Oryza/fisiología , Fotoperiodo , Fitocromo/metabolismo , Proteínas de Plantas/genética , Transcripción Genética , Transporte Activo de Núcleo Celular/efectos de la radiación , Núcleo Celular/metabolismo , Núcleo Celular/efectos de la radiación , Flores/efectos de la radiación , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Luz , Modelos Biológicos , Oryza/anatomía & histología , Oryza/efectos de la radiación , Proteínas de Plantas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Unión Proteica/efectos de la radiación , Estabilidad Proteica/efectos de la radiación , Proteolisis/efectos de la radiación , Protoplastos/metabolismo , Protoplastos/efectos de la radiación , Transcripción Genética/efectos de la radiaciónRESUMEN
Trophic transfer of cyclic methyl siloxanes (CMS) in aquatic ecosystems is an important criterion for assessing its environmental risks. This study researched the trophic transfer of four CMS (octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), dodecamethylcyclohexasiloxane (D6), and tetradecamethylcycloheptasiloxane (D7)) in marine food web from zooplankton up to seabirds in the Chinese Bohai Sea. In the zooplankton-invertebrate-fish-seabird based food web, the significant trophic magnifications were found for D4 to D6 (D4: R2â¯=â¯0.040, pâ¯<â¯0.05, D5: R2â¯=â¯0.26, pâ¯<â¯0.0001, D6: R2â¯=â¯0.071, pâ¯<â¯0.001), and the significant trophic dilution was found for D7 (R2â¯=â¯0.026 and pâ¯<â¯0.05). The trophic magnification factors (TMF) for D4 to D7 were 1.7 (95% confidence interval: 1.1-2.6), 3.5 (2.5-5.0), 1.8 (1.3-2.6), and 0.63 (95% CI: 0.40-0.99) respectively. In the zooplankton-invertebrate-fish based food web, both significant trophic magnification for D5 (R2â¯=â¯0.16, pâ¯<â¯0.0001, TMFâ¯=â¯3.0) and significant trophic dilution for D7 (R2â¯=â¯0.073, pâ¯<â¯0.01, TMFâ¯=â¯0.4) were found, but for D4 and D6, the trophic magnifications were not significant (D4: R2â¯=â¯0.010, pâ¯=â¯0.23, D6: R2â¯=â¯0.010, pâ¯=â¯0.23). The trophic transfer of the legacy contaminant BDE-47 and BDE-99 were also conducted as the benchmark chemicals and significant positive correlation was found. As far as we know, this is the first research on the trophic transfer of CMS in the zooplankton-invertebrate-fish-bird food chain which provided new insight of these compounds in the area.
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Organismos Acuáticos/química , Monitoreo del Ambiente/métodos , Siloxanos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Organismos Acuáticos/metabolismo , Aves/metabolismo , China , Peces/metabolismo , Cadena Alimentaria , Invertebrados/metabolismo , Océanos y Mares , Zooplancton/químicaRESUMEN
Field coupled samples in soil and grass were collected to determine the concentrations and identify the uptake pathways of PCBs into the grass at a pasture from Scotland, UK. Concentrations of indicator PCBs (∑7PCBs) in soils ranged from 0.20 to 0.88â¯ngâ¯g-1 dw (dry weight), with a mean of 0.33â¯ngâ¯g-1 dw, and in grass ranged from 0.20 to 2.14â¯ngâ¯g-1 dw, with a mean of 0.48â¯ngâ¯g-1 dw. The comprehensive factors of low concentrations and detection rate (PCB28: 18.8%; PCB52: 37.5%) of PCBs in soil, as well as continuously declined air concentrations of PCBs in the UK since the 1990s suggested that the secondary emission from the soil is becoming the supplied source of PCBs to air and grass. The significant correlations between bioconcentration factor (BCF) values and the log KOW (Râ¯=â¯-0.850, pâ¯<â¯0.05) and log KOA (Râ¯=â¯-0.860, pâ¯<â¯0.05) of indicator PCB congeners were found in the present study, indicating that these two parameters are likely to affect the bioaccumulation and uptake of grass. A generic one-compartment model was employed to identify uptake pathways of grass and evaluate the uptake amounts for PCBs. This suggested that the most important pathway for uptake of PCBs by grass was at the aerial part, and the difference of PCBs concentrations between leaves and roots was about four orders of magnitude. Removing and risk transfer of PCBs or other organic pollutants by grass need to be investigated and assessed further.
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Monitoreo del Ambiente , Poaceae/química , Bifenilos Policlorados/análisis , Contaminantes del Suelo/análisis , Suelo/química , Contaminantes Ambientales/análisisRESUMEN
The Chinese Gridded Industrial Pollutants Emission and Residue Model (ChnGIPERM) was used to investigate potential fractionation effects and atmospheric transport of polychlorinated biphenyls (PCBs) derived from single-source emissions in China. Modeling the indicative PCBs (CB28, CB101, CB153, and CB180) revealed spatiotemporal trends in atmospheric transport, gas/particle partitioning, and primary and secondary fractionation effects. These included the inference that the Westerlies and East Asian monsoons affect atmospheric transport patterns of PCBs by influencing the atmospheric transport time (ATT). In this study, dispersion pathways with long ATTs in winter tended to have short ones in summer and vice versa. The modeled partitioning of PCB congeners between gas and particles was mainly controlled by temperature, which can further influence the ATT. The potential for primary and secondary fractionation was explored by means of numerical simulations with single-source emissions. Within ChnGIPERM, these phenomena were mainly controlled by the temperature and soil organic carbon content. The secondary fractionation of PCBs is a slow process, with model results suggesting a timescale of several decades.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Modelos Teóricos , Bifenilos Policlorados/análisis , Contaminantes Atmosféricos/química , Fraccionamiento Químico , China , Bifenilos Policlorados/química , Estaciones del Año , Contaminantes del Suelo/análisis , Contaminantes del Suelo/química , Temperatura , Factores de TiempoRESUMEN
By imitating the scaffold of lithocholic acid (LCA), a natural steroidal compound displaying Protein Tyrosine Phosphatase 1B (PTP1B) inhibitory activity, a series of stilbene derivatives containing phenyl-substituted isoxazoles were designed and synthesized. The structures of the title compounds were confirmed by ¹H-NMR, 13C-NMR and HRMS. Activities of the title compounds were evaluated on PTP1B and the homologous enzyme TCPTP by using a colorimetric assay. Most of the target compounds had good activities against PTP1B. Among them, compound 29 (IC50 = 0.91 ± 0.33 µM), characterized by a 5-(2,3-dichlorophenyl) isoxazole moiety, exhibited an activity about 14-fold higher than the lead compound LCA and a 4.2-fold selectivity over TCPTP. Compound 29 was identified as a competitive inhibitor of PTP1B with a Ki value of 0.78 µM in enzyme kinetic studies.
Asunto(s)
Diseño de Fármacos , Isoxazoles/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Estilbenos/química , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Concentración 50 Inhibidora , Isoxazoles/síntesis química , Ácido Litocólico/química , Espectrometría de Masas , Estructura Molecular , Espectroscopía de Protones por Resonancia Magnética , Estilbenos/síntesis química , Relación Estructura-ActividadRESUMEN
OBJECTIVES: To explore the effects of mild hypothemia on hemodynamics of systemic and renal of dog with septic shock. METHODS: 40 healthy dogs were randomly and evenly divided into the normal temperature non-infected group (NTNS), normal temperature infected group (NTS), hypothermia non-infected group (MHNS) and hypothermia infected group (MHS). NTS and MHS were pumped through the femoral vein of Escherichia coli (E.coli 1 × 109 cfu/ml) by 0.5 ml·kg⻹·h⻹, producting septic shock model with high-power cycle. Combining with blood pump devices and low temperature thermostat bath, the MHNS and MHS implemented extracorporeal blood cooling method to maintain the blood in temperature (33 ± 1) °C. 0, 24, 48, 72 h point, tested specimens from femoral vein for renal function. In the 0-72 h. Pulse indicates the continuous cardiac output monitor (PiCCO) monitored systemic hemodynamics on each time point. In the 0-72 h, color Doppler ultrasound (CDFI) measured renal hemodynamic on each time point. RESULTS: There was an increase of SBP (P<0.05), SVR [(2 415 ± 651) dyn·s·cmâ»5 vs (1 613 ± 223) dyn·s·cmâ»5, P=0.01] and RI (P=0.04) in the MHS group comparing with the NTS group from 24 to 72 h. CO [(3.58 ± 0.44) L/min vs (4.18 ± 0.60) L/min, P=0.04], HR and PSV was decreased in the MHS group. BUN [(8.6 ± 1.6) mmol/L vs (21.2 ± 4.8) mmol/L, P<0.01] and Scr [(167.6 ± 31.2) µmol/L vs (383.8 ± 35.2) µmol/L, P<0.01] was decreased in MHS group comparing with the NTS group. There was a positively correlation between CO and PSV in the canine model of septic shock (P<0.01); and CO was negatively correlated with RI (P<0.01). CONCLUSIONS: In this canine model of septic shock, hypothermia can stable systemic and renal hemodynamics, and improve kidney function.
Asunto(s)
Hemodinámica , Choque Séptico , Animales , Gasto Cardíaco , Perros , RiñónRESUMEN
Vegetation net primary production (NPP) is an essential index for determining the quality of terrestrial ecosystems and their potential carbon storage ability. The impacts of extreme climate events on vegetation NPP are different under different altitude gradients. However, the research on the impact of extreme climate events on the spatial variation in vegetation NPP and the coupling effects under different altitude conditions remain insufficient. Using the MOD17A3HGF remote sensing data set and RClimDex 1.9 software, the vegetation NPP and 10 extreme climate indices in the Songhua River Basin from 2001 to 2020 were calculated, respectively. The spatial and temporal evolution characteristics of vegetation NPP and its response mechanism to extreme climate events in the Songhua River Basin under different altitude gradients were analyzed by means of trend analysis, correlation analysis, regression analysis, GeoDetector, and relative importance analysis. The results showed that:â the vegetation NPP (calculated by C) in the Songhua River Basin increased significantly at the rate of 4.13 g·(m2·a)-1 from 2001 to 2020 (P < 0.01), and the rates of 3.65, 4.04, 4.70, 5.09, and 4.57 g·(m2·a)-1 at the altitude gradients of 29-255, 255-440, 440-658, 658-935, and 935-2 589 m, respectively (P < 0.01). â¡ The spatial distribution pattern of vegetation NPP presented "high around and low in the middle," and the fluctuation of vegetation NPP in high altitude areas was more obvious than that in low altitude areas; for example, the average value of vegetation NPP at an altitude gradient from 29 to 255 m had a lower value, whereas the other altitude gradients had higher mean values than the mean value of the basin. ⢠The extreme precipitation events in the Songhua River Basin were the main influencing factors of vegetation NPP, i.e., the vegetation NPP in low-altitude areas was mainly affected by extreme precipitation events, whereas the values in high-altitude areas were affected by both extreme precipitation events and extreme temperature events. The results of this research can provide a scientific basis for improving the carbon cycle model of the terrestrial ecosystem in the Songhua River Basin, quantifying the ability of carbon storage of vegetation and formulating policies to deal with climate change.