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1.
Heliyon ; 10(7): e28365, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38571661

RESUMEN

Aurora kinase A, as a pro-carcinogenic in gastric cancer and glioma kinase, is enhanced in several human tumors. However, it's regulatory mechanism in esophageal squamous cell carcinoma (ESCC) remains unclear. Thus, this study aimed to investigate the expression status, functional roles, and molecular mechanisms of AURKA in ESCC development. AURKA expression was analyzed by the screening of the GEO database and detected using an immunohistochemical method. The biological function of AURKA on ESCC was evaluated in vitro and in vivo. Western blot assay, malondialdehyde (MDA), iron, and glutathione (GSH) kits were utilized to assess changes in ferroptosis. Database analysis results showed that AURKA was a differential gene in ESCC and was highly expressed in human ESCC tissues. Functionally, AURKA knockdown decreased ESCC cell proliferation, invasion, and metastasis both in vitro and in vivo. Moreover, when AURKA was knockdown, cells were more correctly blocked in the G2/M phase, and the ferroptosis-related MDA and Fe increased, whereas the GSH reduced. Consistently, Glutathione peroxidase 4 (GPX4) and solute carrier family 7a member 11 (SLC7A11) expression were downregulated by AURKA knockdown. However, ferroptosis inhibitor partially restore ESCC cell proliferation, invasion, and metastasis caused by AURKA knockdown. AURKA knockdown enhances ferroptosis and acts against cancer progression in ESCC. AURKA acts as a tumor-promoting gene and may serve as potential target for ESCC treatment.

2.
Hypertens Res ; 47(5): 1323-1337, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38491106

RESUMEN

Paroxysmal sympathetic hyperactivity (PSH) is a common clinical feature secondary to ischemic stroke (IS), but its mechanism is poorly understood. We aimed to investigate the role of H2S in the pathogenesis of PSH. IS patients were divided into malignant (MCI) and non-malignant cerebral infarction (NMCI) group. IS in rats was induced by the right middle cerebral artery occlusion (MCAO). H2S donor (NaHS) or inhibitor (aminooxy-acetic acid, AOAA) were microinjected into the hypothalamic paraventricular nucleus (PVN). Compared with the NMCI group, patients in the MCI group showed PSH, including tachycardia, hypertension, and more plasma norepinephrine (NE) that was positively correlated with levels of creatine kinase, glutamate transaminase, and creatinine respectively. The 1-year survival rate of patients with high plasma NE levels was lower. The hypothalamus of rats with MCAO showed increased activity, especially in the PVN region. The levels of H2S in PVN of the rats with MCAO were reduced, while the blood pressure and renal sympathetic discharge were increased, which could be ameliorated by NaHS and exacerbated by AOAA. NaHS completely reduced the disulfide bond of NMDAR1 in PC12 cells. The inhibition of NMDAR by MK-801 microinjected in PVN of rats with MCAO also could lower blood pressure and renal sympathetic discharge. In conclusion, PSH may be associated with disease progression and survival in patients with IS. Decreased levels of H2S in PVN were involved in regulating sympathetic efferent activity after cerebral infarction. Our results might provide a new strategy and target for the prevention and treatment of PSH.


Asunto(s)
Sulfuro de Hidrógeno , Núcleo Hipotalámico Paraventricular , Animales , Núcleo Hipotalámico Paraventricular/metabolismo , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Sulfuro de Hidrógeno/metabolismo , Sulfuro de Hidrógeno/sangre , Masculino , Ratas , Humanos , Anciano , Infarto Cerebral , Persona de Mediana Edad , Ratas Sprague-Dawley , Femenino , Norepinefrina/sangre , Enfermedades del Sistema Nervioso Autónomo , Ácido Aminooxiacético/farmacología , Sistema Nervioso Simpático/fisiopatología , Sistema Nervioso Simpático/efectos de los fármacos , Infarto de la Arteria Cerebral Media/complicaciones , Presión Sanguínea/efectos de los fármacos
3.
Bioinformatics ; 40(2)2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38243719

RESUMEN

SUMMARY: Single-cell RNA-seq (scRNA-seq) is a powerful technique for decoding the complex cellular compositions in the tumor microenvironment (TME). As previous studies have defined many meaningful cell subtypes in several tumor types, there is a great need to computationally transfer these labels to new datasets. Also, different studies used different approaches or criteria to define the cell subtypes for the same major cell lineages. The relationships between the cell subtypes defined in different studies should be carefully evaluated. In this updated package scCancer2, designed for integrative tumor scRNA-seq data analysis, we developed a supervised machine learning framework to annotate TME cells with annotated cell subtypes from 15 scRNA-seq datasets with 594 samples in total. Based on the trained classifiers, we quantitatively constructed the similarity maps between the cell subtypes defined in different references by testing on all the 15 datasets. Secondly, to improve the identification of malignant cells, we designed a classifier by integrating large-scale pan-cancer TCGA bulk gene expression datasets and scRNA-seq datasets (10 cancer types, 175 samples, 663 857 cells). This classifier shows robust performances when no internal confidential reference cells are available. Thirdly, scCancer2 integrated a module to process the spatial transcriptomic data and analyze the spatial features of TME. AVAILABILITY AND IMPLEMENTATION: The package and user documentation are available at http://lifeome.net/software/sccancer2/ and https://doi.org/10.5281/zenodo.10477296.


Asunto(s)
Neoplasias , Programas Informáticos , Humanos , Análisis de Secuencia de ARN/métodos , Microambiente Tumoral , Análisis de la Célula Individual/métodos , Perfilación de la Expresión Génica/métodos , Neoplasias/genética
4.
Nitric Oxide ; 140-141: 77-90, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37875241

RESUMEN

Aging causes vascular endothelial dysfunction. We aimed to investigate the causes of vascular endothelial dysfunction during aging using plasma and renal arteries from patients who underwent nephrectomy and animal models. The results showed that the endogenous H2S-producing enzyme cystathione-γ-lyase (CSE) protein expression was downregulated in renal artery tissue, plasma H2S levels were reduced. Moreover, elevated lipid peroxidation and iron accumulation levels led to ferroptosis and endothelial diastolic function in the renal arteries was impaired in the elderly group. H2S enhanced the endogenous CSE expression in the elderly group, promoted endogenous H2S production, decreased lipid peroxide expression, and inhibited ferroptosis, which in turn improved vascular endothelial function in the elderly group. In animal models, we also observed the same results. In addition, we applied NaHS, Ferrostatin-1 (ferroptosis inhibitor) and erastin (ferroptosis inducer) to incubate renal arteries of SD rats. The results showed that NaHS enhanced ferroptosis related proteins expression, inhibited ferroptosis and improved vascular endothelial function. We demonstrated that endothelial dysfunction associated with aging is closely related to reduced endogenous H2S levels and ferroptosis in vascular endothelial cells. Notably, H2S reduced lipid peroxidation levels in vascular endothelial cells, inhibited ferroptosis in vascular endothelial cells, and improved endothelial dysfunction.


Asunto(s)
Ferroptosis , Sulfuro de Hidrógeno , Humanos , Ratas , Animales , Anciano , Sulfuro de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Células Endoteliales/metabolismo , Ratas Sprague-Dawley , Arterias , Envejecimiento , Cistationina gamma-Liasa/metabolismo
5.
Acta Biochim Biophys Sin (Shanghai) ; 55(9): 1358-1369, 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37587757

RESUMEN

Mounting evidence demonstrates that hydrogen sulfide (H 2S) promotes anti-inflammatory molecules and inhibits pro-inflammatory cytokines in endothelial cells (ECs). This study aims to investigate the favorable action of H 2S on endothelial function in senescence by inhibiting the production of inflammatory molecules. Senescent ECs exhibit a reduction in H 2S, endothelial nitric oxide synthase (eNOS) and peroxisome proliferator-activated receptor δ (PPARδ), coupled with increased inflammatory molecules, sodium glucose transporter type 2 (SGLT2) and phosphorylation of STAT3, which could be reversed by the administration of a slow but sustained release agent of H 2S, GYY4137. Decreased production of eNOS and upregulated p-STAT3 and SGLT2 levels in senescent ECs are reversed by replenishment of the SGLT2 inhibitor EMPA and the PPARδ agonist GW501516. The PPARδ antagonist GSK0660 attenuates eNOS expression and increases the production of p-STAT3 and SGLT2. However, supplementation with GYY4137 has no beneficial effect on GSK0660-treated ECs. GYY4137, GW501516 and EMPA preserve endothelial-dependent relaxation (EDR) in D-gal-treated aortae, while GSK0660 destroys aortic relaxation even with GYY4137 supplementation. In summary, senescent ECs manifest aggravated the expressions of the inflammatory molecules SGLT2 and p-STAT3 and decreased the productions of PPARδ, eNOS and CSE. H 2S ameliorates endothelial dysfunction through the anti-inflammatory effect of the PPARδ/SGLT2/p-STAT3 signaling pathway in senescent ECs and may be a potential therapeutic target for anti-ageing treatment.


Asunto(s)
Sulfuro de Hidrógeno , PPAR delta , Humanos , Células Endoteliales , Sulfuro de Hidrógeno/farmacología , Transportador 2 de Sodio-Glucosa , Inflamación/tratamiento farmacológico , Factor de Transcripción STAT3
6.
Angiology ; : 33197231186493, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37379462

RESUMEN

Contrast-induced acute kidney injury (CI-AKI) is an important complication following the use of iodinated contrast media. Bilirubin has a protective effect but may also aggravate CI-AKI. The purpose of this systematic review was to assess whether bilirubin is a risk factor for CI-AKI. We searched the databases PubMed, Embase, Web of Science, Cochrane Library, Scopus, Ovid Medline, CNKI (China National Knowledge Infrastructure), VPCS (Vip Paper Check System), Wanfang, and CBM (Chinese BioMedical Literature Database) from the initial date to May 6, 2023. We summarized the results by directly combining the effect-size odds ratio (OR) and 95% confidence interval (CI) and identified sources of heterogeneity through subgroup analysis, sensitivity analysis, and meta-regression analysis. A total of 10 studies (14 data sets) were included: 7 retrospective studies (10 data sets) and 3 prospective studies (4 data sets), involving 12776 participants. The incidence of CI-AKI of 16% (95% CI: 14-19%). Total bilirubin was positively associated with the occurrence of CI-AKI (OR = 1.80; 95% CI: 1.36-2.38). Both low and high bilirubin concentrations were risk factors for CI-AKI. The incidence of CI-AKI was higher in the low bilirubin group than in the high bilirubin group.

8.
Eur J Nucl Med Mol Imaging ; 50(9): 2885-2898, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37093313

RESUMEN

PURPOSE: To provide a theory for guiding clinical treatment by comparing the clinical application value of [18F]fluorodeoxyglucose ([18F]FDG) PET/CT and [68Ga]Ga-FAPI (fibroblast activating protein inhibitor) PET/MR in the diagnosis and evaluation of resectability of ovarian cancer. METHODS: Thirty patients with high clinical suspicion of ovarian malignancies were enrolled from July 2021 to October 2022 and underwent [18F]FDG PET/CT and [68Ga]Ga-FAPI-04 PET/MR within 5 days. Twenty patients underwent [18F]FDG PET/MR at once completing [18F]FDG PET/CT for consistency checking. Images were analysed for comparing SUVs and for judging incomplete resectability according to the peritoneal cancer index (PCI) and SUIDAN scoring system. The expression of FAP, HK2 and Ki67 was analysed by immunohistochemistry staining. RESULTS: There was no significant difference between PET/MR and PET/CT in SUVs-FDG at different locations (p > 0.05), and their diagnostic accuracies were similar. The diagnostic accuracy of [68Ga]Ga-FAPI-04 PET/MR had advantages for peritoneal metastasis since SUVsFAPI were higher (p < 0.01). The sensitivity of [68Ga]Ga-FAPI-04 PET/MR in the diagnosis of peridiaghragmatic metastases was higher because SUVmax in the liver was decreased (p < 0.001). [68Ga]Ga-FAPI-04 PET/MR might have advantages in diagnosing gastrointestinal invasion. In PCI score analysis, [68Ga]Ga-FAPI-04 PET/MR could partially correct missing or underestimated scores by [18F]FDG PET/CT, but the matching probability between left peri-intestinal metastasis scores was low and easy to overestimate. Interestingly, diaphragmatic metastasis detected by [68Ga]Ga-FAPI-04 PET/MR had the greatest correlation with the prediction of incomplete resectability (logistic regression p = 0.02). Through immunohistochemistry, the expression of FAP had a strong correlation with SUVmax-FAPI (p < 0.001), while the expression of HK2 was correlated with SUVmax-FDG (p < 0.01). In addition, SUVmax-FDG with Ki67 ≥ 20% was significantly higher than that with Ki67 < 20% (p < 0.05). CONCLUSIONS: [68Ga]Ga-FAPI-04 PET/MR had obvious advantages for metastases diagnosis and could more accurately assess tumour load and predict incomplete resectability. SUVmax-FDG was conducive to evaluating the degree of tumour malignancy.


Asunto(s)
Neoplasias Ováricas , Quinolinas , Humanos , Femenino , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radioisótopos de Galio , Antígeno Ki-67 , Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/cirugía
9.
Genomics Proteomics Bioinformatics ; 20(5): 974-988, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36549467

RESUMEN

Sequencing-based spatial transcriptomics (ST) is an emerging technology to study in situ gene expression patterns at the whole-genome scale. Currently, ST data analysis is still complicated by high technical noises and low resolution. In addition to the transcriptomic data, matched histopathological images are usually generated for the same tissue sample along the ST experiment. The matched high-resolution histopathological images provide complementary cellular phenotypical information, providing an opportunity to mitigate the noises in ST data. We present a novel ST data analysis method called transcriptome and histopathological image integrative analysis for ST (TIST), which enables the identification of spatial clusters (SCs) and the enhancement of spatial gene expression patterns by integrative analysis of matched transcriptomic data and images. TIST devises a histopathological feature extraction method based on Markov random field (MRF) to learn the cellular features from histopathological images, and integrates them with the transcriptomic data and location information as a network, termed TIST-net. Based on TIST-net, SCs are identified by a random walk-based strategy, and gene expression patterns are enhanced by neighborhood smoothing. We benchmark TIST on both simulated datasets and 32 real samples against several state-of-the-art methods. Results show that TIST is robust to technical noises on multiple analysis tasks for sequencing-based ST data and can find interesting microstructures in different biological scenarios. TIST is available at http://lifeome.net/software/tist/ and https://ngdc.cncb.ac.cn/biocode/tools/BT007317.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Perfilación de la Expresión Génica/métodos , Procesamiento de Imagen Asistido por Computador/métodos
10.
Behav Sci (Basel) ; 12(11)2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36354409

RESUMEN

As social innovations that help to transition towards a more sustainable food system, alternative food networks (AFNs) in China have attracted much scholarly attention in recent years. However, studies of the community building behavior of AFNs at the micro-level in the Chinese social context are scant. Through in-depth case studies conducted between 2017 and 2021 and social network analysis, our study examines how founders of AFNs successfully facilitate community building among their customers. We find that in China, the traditional social-cultural construct, guanxi, plays a critical role in AFNs' community formation and expansion. The study identifies a three-stage framework for understanding the community building process of AFNs. First, a group of guanxi of the same kind would form a guanxi-circle. Second, the initial guanxi-circle is enhanced and expanded to multiple secondary guanxi-circles. Third, these multiple guanxi-circles together and the interactions among them constitute the community of AFNs. We argue that to strengthen the community, AFNs operators should inspire key members to form secondary guanxi-circles by enhancing their cognitive trust and emotional trust.

11.
Front Mol Biosci ; 9: 947778, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35936785

RESUMEN

Aging contributes significantly to cardiovascular diseases and cardiac dysfunction. To explore the reasons for the decline in cardiac function in the elderly, we collected clinical data and blood samples from 231 individuals. Our results indicated that aging was accompanied by a decline in cardiac function and remodeling of the left ventricle, and cardiac function was negatively correlated with age. Serum hydrogen sulfide (H2S) decreased, while serum malondialdehyde (MDA) and iron increased with aging in healthy individuals. A rat model of aging and iron overload was constructed for in vivo research. In the animal model, we found that the expression of endogenous H2S-producing enzymes decreased, and endogenous H2S levels decreased, while oxidative stress levels rose. The regulation of iron metabolism and the maintenance of iron homeostasis declined. The accumulation of MDA and iron led to ferroptotic cell death and subsequent myocardial injury and deterioration. A high-iron diet accelerated the aging process and death in rats. The decline of cardiac function in aging rats and iron-overload rats may be caused by cardiomyocyte ferroptosis. Exogenous H2S enhanced the expression of endogenous H2S synthase, promoted endogenous H2S production, regulated iron metabolism, and reduced oxidative stress levels. The protective effects of H2S on cardiac function in aging rats and iron-overload rats may be partly due to the inhibition of cardiomyocyte ferroptosis. We demonstrated that cardiac dysfunction associated with aging was closely related to decreased endogenous H2S levels and cardiomyocyte ferroptosis. H2S-regulated iron metabolism reduced oxidative stress levels in cardiomyocytes, inhibited cardiomyocyte ferroptosis, and protected cardiac function in aging rats.

12.
Front Plant Sci ; 13: 890892, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35755650

RESUMEN

Timely and accurate estimation of plant nitrogen (N) status is crucial to the successful implementation of precision N management. It has been a great challenge to non-destructively estimate plant N status across different agro-ecological zones (AZs). The objective of this study was to use random forest regression (RFR) models together with multi-source data to improve the estimation of winter wheat (Triticum aestivum L.) N status across two AZs. Fifteen site-year plot and farmers' field experiments involving different N rates and 19 cultivars were conducted in two AZs from 2015 to 2020. The results indicated that RFR models integrating climatic and management factors with vegetation index (R2 = 0.72-0.86) outperformed the models by only using the vegetation index (R2 = 0.36-0.68) and performed well across AZs. The Pearson correlation coefficient-based variables selection strategy worked well to select 6-7 key variables for developing RFR models that could achieve similar performance as models using full variables. The contributions of climatic and management factors to N status estimation varied with AZs and N status indicators. In higher-latitude areas, climatic factors were more important to N status estimation, especially water-related factors. The addition of climatic factors significantly improved the performance of the RFR models for N nutrition index estimation. Climatic factors were important for the estimation of the aboveground biomass, while management variables were more important to N status estimation in lower-latitude areas. It is concluded that integrating multi-source data using RFR models can significantly improve the estimation of winter wheat N status indicators across AZs compared to models only using one vegetation index. However, more studies are needed to develop unmanned aerial vehicles and satellite remote sensing-based machine learning models incorporating multi-source data for more efficient monitoring of crop N status under more diverse soil, climatic, and management conditions across large regions.

13.
Molecules ; 24(9)2019 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-31086063

RESUMEN

Lentinus edodes, whose polysaccharides possess diverse bioactivities, commonly grows on hardwood sawdust composed of hemicellulose, lignin and cellulose. In this study the effect of hemicellulose and lignin on the growth of mycelia, as well as the physicochemical properties of polysaccharides from L. edodes mycelia (LEPs) were investigated. The antioxidant properties of LEPs were evaluated through radical scavenging assays in vitro and through the Caenorhabditis elegans model in vivo. The results showed that hemicellulose at a concentration of 4% increased the yield of the mycelia biomass to twice that of the control group. Meanwhile, when cultured with 4.0% hemicellulose, the polysaccharide content of the mycelia was raised by 112.2%. In addition, the appropriate concentration of lignin could stimulate mycelia growth and polysaccharide biosynthesis in L. edodes. Monosaccharide composition analysis showed that a higher content of xylose was found when mycelia were cultured with higher concentrations of hemicellulose. The molecular structure, including the molecular weight distribution and configuration type, was affected by hemicellulose and lignin. Antioxidant assays indicated that LEPs supplemented with hemicellulose and/or lignin possessed higher radical scavenging abilities in vitro and exhibited a thermal resistance effect on C. elegans, implying that the antioxidant effect is potent in vivo. In summary, the addition of hemicellulose and lignin improved the biosynthesis and bioactivity of LEPs.


Asunto(s)
Antioxidantes/química , Lignina/química , Polisacáridos/química , Hongos Shiitake/química , Animales , Caenorhabditis elegans/efectos de los fármacos , Monosacáridos/química , Polisacáridos/farmacología
15.
AoB Plants ; 10(5): ply054, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30338049

RESUMEN

The adaptations of root growth and rhizosphere processes for soil phosphorus (P) acquisition have been investigated intensively in wheat (Triticum aestivum). However, only a few studies paid attention to these responses to shoot P status. This study aimed at investigating the responses of root morphology and P-mobilizing exudation to increasing shoot P concentration. A broad range of wheat shoot P concentrations (1.0-7.1 mg per g dry weight) was set up with 11 rates of P supply: 0-1200 mg P per kg soil. Root morphology and exudation parameters were measured after 37 days of plant growth. Shoot dry biomass reached a maximum when shoot P concentration was 4.63 mg per g dry weight. The maximum shoot P concentration for total root length, specific root length and the proportion of fine root (diameter ≤ 0.2 mm) length to total root length was 3 mg per g dry weight. Rhizosphere acidification was positively correlated with shoot P concentration when this was <5 mg per g dry weight. Shoot P concentration did not change acid phosphatase activity in the rhizosphere. Citrate concentration in the rhizosphere was suppressed by increasing shoot P concentration. In contrast, malate concentration in the rhizosphere showed a positive correlation with shoot P concentration. In conclusion, wheat root morphological and P-mobilizing exudation traits showed different behaviours with increasing P deficiency stress. Maintaining root biomass and length is the major strategy rather than root exudation for wheat to cope with extreme P deficiency.

16.
Gene ; 661: 139-151, 2018 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-29605602

RESUMEN

Ganoderma lucidum is a valuable basidiomycete with numerous pharmacological compounds, which is widely consumed throughout China. We previously found that the polysaccharide content of Ganoderma lucidum fruiting bodies could be significantly improved by 45.63% with treatment of 42 °C heat stress (HS) for 2 h. To further investigate genes involved in HS response and explore the mechanisms of HS regulating the carbohydrate metabolism in Ganoderma lucidum, high-throughput RNA-Seq was conducted to analyse the difference between control and heat-treated mycelia at transcriptome level. We sequenced six cDNA libraries with three from control group (mycelia cultivated at 28 °C) and three from heat-treated group (mycelia subjected to 42 °C for 2 h). A total of 99,899 transcripts were generated using Trinity method and 59,136 unigenes were annotated by seven public databases. Among them, 2790 genes were identified to be differential expressed genes (DEGs) under HS condition, which included 1991 up-regulated and 799 down-regulated. 176 DEGs were then manually classified into five main responsive-related categories according to their putative functions and possible metabolic pathways. These groups include stress resistance-related factors; protein assembly, transportation and degradation; signal transduction; carbohydrate metabolism and energy provision-related process; other related functions, suggesting that a series of metabolic pathways in Ganoderma lucidum are activated by HS and the response mechanism involves a complex molecular network which needs further study. Remarkably, 48 DEGs were found to regulate carbohydrate metabolism, both in carbohydrate hydrolysis for energy provision and polysaccharide synthesis. In summary, this comprehensive transcriptome analysis will provide enlarged resource for further investigation into the molecular mechanisms of basidiomycete under HS condition.


Asunto(s)
Respuesta al Choque Térmico/genética , Reishi/genética , Estrés Fisiológico/genética , Transcriptoma , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Secuenciación de Nucleótidos de Alto Rendimiento , Redes y Vías Metabólicas/genética , Anotación de Secuencia Molecular , Reishi/metabolismo , Análisis de Secuencia de ADN
17.
Nature ; 555(7696): 363-366, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29513654

RESUMEN

Sustainably feeding a growing population is a grand challenge, and one that is particularly difficult in regions that are dominated by smallholder farming. Despite local successes, mobilizing vast smallholder communities with science- and evidence-based management practices to simultaneously address production and pollution problems has been infeasible. Here we report the outcome of concerted efforts in engaging millions of Chinese smallholder farmers to adopt enhanced management practices for greater yield and environmental performance. First, we conducted field trials across China's major agroecological zones to develop locally applicable recommendations using a comprehensive decision-support program. Engaging farmers to adopt those recommendations involved the collaboration of a core network of 1,152 researchers with numerous extension agents and agribusiness personnel. From 2005 to 2015, about 20.9 million farmers in 452 counties adopted enhanced management practices in fields with a total of 37.7 million cumulative hectares over the years. Average yields (maize, rice and wheat) increased by 10.8-11.5%, generating a net grain output of 33 million tonnes (Mt). At the same time, application of nitrogen decreased by 14.7-18.1%, saving 1.2 Mt of nitrogen fertilizers. The increased grain output and decreased nitrogen fertilizer use were equivalent to US$12.2 billion. Estimated reactive nitrogen losses averaged 4.5-4.7 kg nitrogen per Megagram (Mg) with the intervention compared to 6.0-6.4 kg nitrogen per Mg without. Greenhouse gas emissions were 328 kg, 812 kg and 434 kg CO2 equivalent per Mg of maize, rice and wheat produced, respectively, compared to 422 kg, 941 kg and 549 kg CO2 equivalent per Mg without the intervention. On the basis of a large-scale survey (8.6 million farmer participants) and scenario analyses, we further demonstrate the potential impacts of implementing the enhanced management practices on China's food security and sustainability outlook.


Asunto(s)
Agricultura/métodos , Conservación de los Recursos Naturales , Productos Agrícolas/crecimiento & desarrollo , Eficiencia Organizacional , Agricultores , China , Técnicas de Apoyo para la Decisión , Grano Comestible/crecimiento & desarrollo , Política Ambiental , Fertilizantes/estadística & datos numéricos , Abastecimiento de Alimentos/métodos , Efecto Invernadero , Nitrógeno/metabolismo , Oryza/crecimiento & desarrollo , Triticum/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo
18.
Sci Rep ; 7(1): 14073, 2017 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-29074943

RESUMEN

RapidSCAN is a new portable active crop canopy sensor with three wavebands in red, red-edge, and near infrared spectral regions. The objective of this study was to determine the potential and practical approaches of using this sensor for non-destructive diagnosis of rice nitrogen (N) status. Sixteen plot experiments and ten on-farm experiments were conducted from 2014 to 2016 in Jiansanjiang Experiment Station of the China Agricultural University and Qixing Farm in Northeast China. Two mechanistic and three semi-empirical approaches using the sensor's default vegetation indices, normalized difference vegetation index and normalized difference red edge, were evaluated in comparison with the top performing vegetation indices selected from 51 tested indices. The results indicated that the most practical and stable method of using the RapidSCAN sensor for rice N status diagnosis is to calculate N sufficiency index with the default vegetation indices and then to estimate N nutrition index non-destructively (R2 = 0.50-0.59). This semi-empirical approach achieved a diagnosis accuracy rate of 59-76%. The findings of this study will facilitate the application of the RapidSCAN active sensor for rice N status diagnosis across growth stages, cultivars and site-years, and thus contributing to precision N management for sustainable intensification of agriculture.


Asunto(s)
Productos Agrícolas/química , Nitrógeno/análisis , Oryza/química , Espectrofotometría Infrarroja/métodos , Agricultura/instrumentación , Agricultura/métodos , Biomasa , Calibración , Distribución Aleatoria , Espectrofotometría Infrarroja/instrumentación
19.
Nature ; 537(7622): 671-674, 2016 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-27602513

RESUMEN

Sustainably feeding the world's growing population is a challenge, and closing yield gaps (that is, differences between farmers' yields and what are attainable for a given region) is a vital strategy to address this challenge. The magnitude of yield gaps is particularly large in developing countries where smallholder farming dominates the agricultural landscape. Many factors and constraints interact to limit yields, and progress in problem-solving to bring about changes at the ground level is rare. Here we present an innovative approach for enabling smallholders to achieve yield and economic gains sustainably via the Science and Technology Backyard (STB) platform. STB involves agricultural scientists living in villages among farmers, advancing participatory innovation and technology transfer, and garnering public and private support. We identified multifaceted yield-limiting factors involving agronomic, infrastructural, and socioeconomic conditions. When these limitations and farmers' concerns were addressed, the farmers adopted recommended management practices, thereby improving production outcomes. In one region in China, the five-year average yield increased from 67.9% of the attainable level to 97.0% among 71 leading farmers, and from 62.8% to 79.6% countywide (93,074 households); this was accompanied by resource and economic benefits.


Asunto(s)
Producción de Cultivos/métodos , Producción de Cultivos/estadística & datos numéricos , Agricultores/estadística & datos numéricos , Triticum/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , China , Cambio Climático , Producción de Cultivos/economía , Ecología , Política Ambiental , Nitrógeno , Población Rural , Semillas , Factores Socioeconómicos , Factores de Tiempo , Agua
20.
Chem Commun (Camb) ; 51(100): 17728-31, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26489890

RESUMEN

Manganese oxide-doped Al2O3 microspheres were synthesized via a redox method, and were then deposited with Au nanoparticles using a deposition-precipitation method. The obtained catalyst is not only highly active and selective for the preferential oxidation of CO in a H2-rich stream, but also shows excellent stability in the co-presence of H2O and CO2 at 80 °C.

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