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1.
Opt Express ; 32(4): 5056-5071, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439242

RESUMO

Quantum random number generator (QRNG) utilizes the intrinsic randomness of quantum systems to generate completely unpredictable and genuine random numbers, finding wide applications across many fields. QRNGs relying on the phase noise of a laser have attracted considerable attention due to their straightforward system architecture and high random number generation rates. However, traditional phase noise QRNGs suffer from a 50% loss of quantum entropy during the randomness extraction process. In this paper, we propose a phase-reconstruction quantum random number generation scheme, in which the phase noise of a laser is reconstructed by simultaneously measuring the orthogonal quadratures of the light field using balanced detectors. This enables direct discretization of uniform phase noise, and the min-entropy can achieve a value of 1. Furthermore, our approach exhibits inherent robustness against the classical phase fluctuations of the unbalanced interferometer, eliminating the need for active compensation. Finally, we conducted experimental validation using commercial optical hybrid and balanced detectors, achieving a random number generation rate of 1.96 Gbps at a sampling rate of 200 MSa/s.

2.
Compr Rev Food Sci Food Saf ; 23(3): e13349, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38638060

RESUMO

3D printing is an additive manufacturing technology that locates constructed models with computer-controlled printing equipment. To achieve high-quality printing, the requirements on rheological properties of raw materials are extremely restrictive. Given the special structure and high modifiability under external physicochemical factors, the rheological properties of proteins can be easily adjusted to suitable properties for 3D printing. Although protein has great potential as a printing material, there are many challenges in the actual printing process. This review summarizes the technical considerations for protein-based ink 3D printing. The physicochemical factors used to enhance the printing adaptability of protein inks are discussed. The post-processing methods for improving the quality of 3D structures are described, and the application and problems of fourth dimension (4D) printing are illustrated. The prospects of 3D printing in protein manufacturing are presented to support its application in food and cultured meat. The native structure and physicochemical factors of proteins are closely related to their rheological properties, which directly link with their adaptability for 3D printing. Printing parameters include extrusion pressure, printing speed, printing temperature, nozzle diameter, filling mode, and density, which significantly affect the precision and stability of the 3D structure. Post-processing can improve the stability and quality of 3D structures. 4D design can enrich the sensory quality of the structure. 3D-printed protein products can meet consumer needs for nutritional or cultured meat alternatives.


Assuntos
Tinta , Impressão Tridimensional , Alimentos , Carne in vitro , Substitutos da Carne
3.
Angew Chem Int Ed Engl ; 63(11): e202313930, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38055202

RESUMO

Life science has progressed with applications of fluorescent probes-fluorophores linked to functional units responding to biological events. To meet the varied demands across experiments, simple organic reactions to connect fluorophores and functional units have been developed, enabling the on-demand selection of fluorophore-functional unit combinations. However, organic synthesis requires professional equipment and skills, standing as a daunting task for life scientists. In this study, we present a simple, fast, and convenient strategy for probe preparation: co-aggregation of hydrophobic molecules. We focused on tetrazine-a difficult-to-prepare yet useful functional unit that provides effective bioorthogonal reactivity and strong fluorogenicity. Simply mixing the tetrazine molecules and aggregation-induced emission (AIE) luminogens in water, co-aggregation is induced, and the emission of AIE luminogens is quenched. Subsequent click reaction bioorthogonally turns on the emission, identifying these coaggregates as fluorogenic probes. Thanks to this bioorthogonal fluorogenicity, we established a new time-gated fluorescence bioimaging technique to distinguish overlapping emission signals, enabling multi-organelle imaging with two same-color fluorophores. Our study showcases the potential of this co-aggregation method for the on-demand preparation of fluorescent probes as well as protocols and molecular design principles in this approach, offering an effective solution to evolving needs in life science research.

4.
Environ Res ; 239(Pt 1): 117345, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37821065

RESUMO

Owing to accelerated urbanization and industrialization, many plastic products have been manufactured and discharged into the environment, causing environmental and public health problems. Plastics in environmental media are further degraded by prolonged exposure to light, heat, mechanical friction, and other factors to form new pollutants called microplastics (MPs). Medical plastics have become a crucial source of plastics in environmental media. However, the release profiles of MPs from medical plastics and their potential ecological and health risks remain unclear. We used optical photothermal infrared spectroscopy to explore the release profiles of eight typical disposable medical devices under high-temperature steam disinfection (HSD). We also evaluated the toxicity of disposable medical devices-derived MPs in Caenorhabditis elegans (C. elegans). Our results showed that the changes in the surface morphology and modification of the disposable medical devices were mainly associated with the material. Polypropylene (PP) and polystyrene (PS) materials exhibited high aging phenomena (e.g., bumps, depressions, bulges and cracks), and HSD broke their oxygen-containing functional groups and carbon chains. By contrast, minor changes in the chemical and physical properties were observed in the polyvinyl chloride (PVC)-prepared disposable medical devices under the same conditions. Further physicochemical characterization indicated that the amount of MPs released from PP-prepared disposable medical devices (P4: 1.27 ± 0.34 × 106) was greater than that from PVC-prepared disposable medical devices (P7: 1.08 ± 0.14 × 105). The particle size of the released MPs was the opposite, PVC-prepared disposable medical devices (P7: 11.45 ± 1.79 µm) > PP-prepared disposable medical devices (P4: 7.18 ± 0.52 µm). Toxicity assessment revealed that disposable medical devices-released MPs significantly increased germ cell apoptosisin C. elegans. Moreover, MPs from PP-prepared disposable medical devices disrupted the intestinal barrier of worms, decreasing their lifespan. Our findings provided novel information regarding the profiles and mechanisms of MP release from disposable medical devices and revealed their potential risks to ecological environment.


Assuntos
Microplásticos , Plásticos , Animais , Microplásticos/toxicidade , Caenorhabditis elegans , Polipropilenos , Carbono
5.
Int J Mol Sci ; 24(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38139049

RESUMO

Microplastics (MPs) are emerging pollutants and pose a significant threat to marine ecosystems. Although previous studies have documented the mechanisms and toxic effects of aging MPs in various environments, the impact of the marine environment on MPs remains unclear. In the present study, the aging process of polystyrene (PS) in seawater was simulated and the changes in its physicochemical properties were investigated. Our results showed that the surface of the PS eroded in the seawater, which was accompanied by the release of aged MPs with a smaller size. In situ optical photothermal infrared microspectroscopy revealed that the mechanism of PS aging was related to the opening of the carbonyl group and breaking of the bond between carbon and benzene removal. To verify the toxic effects of aged PS, Caenorhabditis elegans was exposed to PS. Aged PS resulted in a greater reduction in locomotion, vitality, and reproduction than virgin PS. Mechanistically, aged PS led to oxidative stress, high glutathione s-transferase activity, and high total glutathione in worms. Together, our findings provided novel information regarding the accelerated aging of PS in seawater and the increased toxicity of aged PS, which could improve our understanding of MPs' ecotoxicity in the marine environment.


Assuntos
Poliestirenos , Poluentes Químicos da Água , Animais , Poliestirenos/toxicidade , Poliestirenos/química , Plásticos , Caenorhabditis elegans , Ecossistema , Microplásticos/química , Envelhecimento , Água do Mar/química
6.
New Phytol ; 236(6): 2233-2248, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36059081

RESUMO

Although some nucleotide binding, leucine-rich repeat immune receptor (NLR) proteins conferring resistance to specific viruses have been identified in dicot plants, NLR proteins involved in viral resistance have not been described in monocots. We have used map-based cloning to isolate the CC-NB-LRR (CNL) Barley stripe mosaic virus (BSMV) resistance gene barley stripe resistance 1 (BSR1) from Brachypodium distachyon Bd3-1 inbred line. Stable BSR1 transgenic Brachypodium line Bd21-3, barley (Golden Promise) and wheat (Kenong 199) plants developed resistance against BSMV ND18 strain. Allelic variation analyses indicated that BSR1 is present in several Brachypodium accessions collected from countries in the Middle East. Protein domain swaps revealed that the intact LRR domain and the C-terminus of BSR1 are required for resistance. BSR1 interacts with the BSMV ND18 TGB1 protein in planta and shows temperature-sensitive antiviral resistance. The R390 and T392 residues of TGB1ND (ND18 strain) and the G196 and K197 residues within the BSR1 P-loop motif are key amino acids required for immune activation. BSR1 is the first cloned virus resistance gene encoding a typical CNL protein in monocots, highlighting the utility of the Brachypodium model for isolation and analysis of agronomically important genes for crop improvement.


Assuntos
Brachypodium , Hordeum , Hordeum/genética , Brachypodium/genética , Proteínas de Repetições Ricas em Leucina , Domínios Proteicos
7.
Opt Express ; 30(23): 41028-41047, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366589

RESUMO

In this paper, we numerically study the secrecy performance of the free-space optical (FSO) system by considering different eavesdropping scenarios. More precisely, we considered three possible eavesdropping scenarios for Eve: 1) Eve is between Alice and Bob; 2) Eve and Bob are in the same receiving plane; 3) Eve is behind Bob. We adopt the Málaga (M)-distribution channel to model atmospheric turbulence due to the presence of link blockage while considering the non-zero boresight pointing error and path loss. To do so, we obtain a novel probability density function (PDF) and cumulative distribution function (CDF) under different eavesdropping scenarios, based on which we derived the secrecy outage probability (SOP) analytical expressions as well as their asymptotic expressions at a high SNR regime. We verified the results using Monte Carlo simulations, which showed that the parameters related to atmospheric turbulence and pointing errors, as well as the location of the eavesdropper, have different effects on different eavesdropping scenarios.

8.
J Exp Bot ; 73(3): 770-783, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34050753

RESUMO

Plants have evolved complex mechanisms to adapt to the changing nitrogen levels in the environment. In Arabidopsis, more than a dozen nitrate signaling regulatory genes have been characterized, including the NODULE INCEPTION-LIKE PROTEIN (AtNLP) genes, which play essential roles in nitrate signaling. However, whether NLP genes in the Triticeae crops are involved in nitrate regulation and nitrogen use efficiency (NUE) remains unknown. Here, we isolated a barley (Hordeum vulgare L.) mutant, hvnlp2-1, from a TILLING (Targeting Local Lesions IN Genomes) population and constructed two RNAi lines, hvnlp2-2 and hvnlp2-3, to study the function of HvNLP2. The expression of the nitrate-responsive genes was substantially inhibited after nitrate treatment in the hvnlp2 mutants, indicating that HvNLP2 controls nitrate signaling. Nitrate content was significantly higher in the hvnlp2 mutants, which may result from the decreased assimilation of nitrogen caused by reduced nitrate reductase activity and expression of nitrate assimilatory genes. HvNLP2 is localized to the nucleus in the presence of nitrate. Further investigation showed that HvNLP2 binds to and activates the nitrate-responsive cis-elements. Moreover, hvnlp2 exhibited reduced biomass, seed yield, and NUE. Therefore, HvNLP2 controls nitrate signaling and plays an important role in NUE.


Assuntos
Hordeum , Nitratos , Produtos Agrícolas/genética , Hordeum/genética , Hordeum/metabolismo , Nitratos/metabolismo , Nitrogênio/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
9.
Theor Appl Genet ; 135(8): 2907-2923, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35794218

RESUMO

KEY MESSAGE: TaD11-2A affects grain size and root length and its natural variations are associated with significant differences in yield-related traits in wheat. Brassinosteroids (BRs) control many important agronomic traits and therefore the manipulation of BR components could improve crop productivity and performance. However, the potential effects of BR-related genes on yield-related traits and stress tolerance in wheat (Triticum aestivum L.) remain poorly understood. Here, we identified TaD11 genes in wheat (rice D11 orthologs) that encoded enzymes involved in BR biosynthesis. TaD11 genes were highly expressed in roots (Zadoks scale: Z11) and grains (Z75), while expression was significantly suppressed by exogenous BR (24-epiBL). Ectopic expression of TaD11-2A rescued the abnormal panicle structure and plant height (PH) of the clustered primary branch 1 (cpb1) mutant, and also increased endogenous BR levels, resulting in improved grain yields and grain quality in rice. The tad11-2a-1 mutant displayed dwarfism, smaller grains, sensitivity to 24-epiBL, and reduced endogenous BR contents. Natural variations in TaD11-2A were associated with significant differences in yield-related traits, including PH, grain width, 1000-grain weight, and grain yield per plant, and its favorable haplotype, TaD11-2A-HapI was subjected to positive selection during wheat breeding. Additionally, TaD11-2A influenced root length and salt tolerance in rice and wheat at seedling stages. These results indicated the important role of BR TaD11 biosynthetic genes in controlling grain size and root length, and also highlighted their potential in the molecular biological analysis of wheat.


Assuntos
Oryza , Triticum , Brassinosteroides , Grão Comestível/genética , Grão Comestível/metabolismo , Regulação da Expressão Gênica de Plantas , Haplótipos , Oryza/genética , Oryza/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triticum/genética , Triticum/metabolismo
10.
Mikrochim Acta ; 189(3): 131, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35239060

RESUMO

An ultra-sensitive glyphosate nanosensor, based on carbon dots (CDs), was successfully developed with excellent long-wavelength emission (530 nm), a high quantum yield (41.3%), and an impressive detection limit (0.8 ng·mL-1). This is the lowest value for glyphosate detection achieved by CD-based fluorescence analysis. The sensor was derived from a separate precursor, 1,4-dihydroxyanthraquinone, and was based on the "off-on" fluorescence analysis, where Cu2+ acts as a dynamic quencher and glyphosate as a fluorescence restorer (excitation wavelength 460 nm). Trace detection of glyphosate is possible with a wide detection range of 50-1300 ng·mL-1 and spiked recoveries between 93.3 and 110.0%. Exploration in depth confirmed that (1) the fluorescence of CDs was derived from the carbon core, (2) the large sp2 conjugated domain consisting of graphitic carbon and nitrogen contributed to the long-wavelength emission, and (3) CDs had an impressive binding interaction with Cu2+, which endow high sensitivity to glyphosate detection. The nanosensor has also be used as a dual-mode visual sensor and a smart sensing membrane that can identify glyphosate on the surface of vegetables, thus showing good practical applicability. Synthetic methods of G-CDs and its detection mechanisms for glyphosate.


Assuntos
Corantes Fluorescentes , Pontos Quânticos , Carbono/química , Corantes Fluorescentes/química , Glicina/análogos & derivados , Íons , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Verduras , Glifosato
11.
Int J Mol Sci ; 23(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36077059

RESUMO

Wheat stripe (yellow) rust is a worldwide disease that seriously reduces wheat grain yield and quality. Adult-plant resistance (APR) to stripe rust is generally more durable but usually controlled by multiple genes with partial resistance. In this study, a recombinant inbred line population was developed from a cross between a Chinese wheat landrace, Tutoumai, with APR to stripe rust, and a highly susceptible wheat cultivar, Siyang 936. The population was genotyped by genotyping-by-sequencing and phenotyped for APR to stripe rust in four consecutive field experiments. Three QTLs, QYr.sdau-1BL, QYr.sdau-5BL, and QYr.sdau-6BL, were identified for APR to stripe rust, and explained 8.0-21.2%, 10.1-22.7%, and 11.6-18.0% of the phenotypic variation, respectively. QYr.sdau-1BL was further mapped to a 21.6 Mb region using KASP markers derived from SNPs identified by RNA-seq of the two parents. In the QYr.sdau-1BL region, 13 disease-resistance-related genes were differently expressed between the two parents, and therefore were considered as the putative candidates of QYr.sdau-1BL. This study provides favorable gene/QTL and high-throughput markers to breeding programs for marker-assisted selection of the wheat stripe rust APR genes.


Assuntos
Basidiomycota , Triticum , Basidiomycota/genética , China , Mapeamento Cromossômico , Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genética
12.
Theor Appl Genet ; 134(9): 2857-2873, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34075443

RESUMO

KEY MESSAGE: High-resolution genome-wide association study (GWAS) facilitated QTL fine mapping and candidate gene identification, and the GWAS based genomic prediction models were highly predictive and valuable in wheat genomic breeding. Wheat is a major staple food crop and provides more than one-fifth of the daily calories and dietary proteins for humans. Genome-wide association study (GWAS) and genomic selection (GS) for wheat stress resistance and tolerance related traits are critical to understanding their genetic architecture for improvement of breeding selection efficiency. However, the insufficient marker density in previous studies limited the utility of GWAS and GS in wheat genomic breeding. Here, we conducted a high-resolution GWAS for wheat leaf rust (LR), yellow rust (YR), powdery mildew (PM), and cold tolerance (CT) by genotyping a panel of 768 wheat cultivars using genotyping-by-sequencing. Among 153 quantitative trait loci (QTLs) identified, 81 QTLs were delimited to ≤ 1.0 Mb intervals with three validated using bi-parental populations. Furthermore, 837 stress resistance-related genes were identified in the QTL regions with 12 showing induced expression by YR and PM pathogens. Genomic prediction using 2608, 4064, 3907, and 2136 pre-selected SNPs based on GWAS and genotypic correlations between the SNPs showed high prediction accuracies of 0.76, 0.73, and 0.78 for resistance to LR, YR, and PM, respectively, and 0.83 for resistance to cold damage. Our study laid a solid foundation for large-scale QTL fine mapping, candidate gene validation and GS in wheat.


Assuntos
Cromossomos de Plantas/genética , Temperatura Baixa , Resistência à Doença/imunologia , Genoma de Planta , Doenças das Plantas/imunologia , Proteínas de Plantas/metabolismo , Triticum/genética , Basidiomycota/fisiologia , Mapeamento Cromossômico/métodos , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Triticum/crescimento & desenvolvimento , Triticum/microbiologia
13.
BMC Geriatr ; 21(1): 191, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33740914

RESUMO

OBJECTIVE: The purpose of this study was to examine whether muscle mass, muscle strength, and physical performance were associated with metabolic syndrome (MetS) in community-dwelling older Chinese adults. METHODS: The study comprised of 1413 community-dwelling Chinese participants (577 men; mean ± standard deviation age: 71.3 ± 5.9) recruited from Tianjin and Shanghai, China who were invited to participate in a comprehensive geriatric assessment. The International Diabetes Federation metabolic syndrome guidelines were used to define MetS, including high waist circumference, elevated blood pressure, elevated fasting blood glucose, elevated triglycerides, and reduced HDL cholesterol. Muscle mass was measured by appendicular skeletal muscle mass/weight (ASM/weight), and ASM was measured by BIA. Muscle strength was measured using grip strength. Physical performance was represented by walking speed and the time up and go test (TUGT). RESULTS: The overall prevalence of MetS was 46.8% (34.1% in males and 55.5% in females). In the final logistic regression model, there was a significant, graded inverse association between muscle mass and MetS (p for trend = 0.014). Muscle strength and physical performance, including walking speed and TUGT, were not associated with overall MetS. In the components of MetS, muscle mass and grip strength were significantly inversely associated with high waist circumference and elevated blood pressure (p < 0.05), while physical performance was not associated with components of MetS. CONCLUSIONS: Compared with muscle strength and muscle function, muscle mass was inversely associated with MetS in a community-dwelling elderly Chinese population. Among muscle mass、muscle strength and physical performance, muscle mass appears to have the strongest association with MetS in the elderly.


Assuntos
Síndrome Metabólica , Idoso , China/epidemiologia , Estudos Transversais , Feminino , Força da Mão , Humanos , Vida Independente , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Força Muscular , Músculos , Desempenho Físico Funcional , Equilíbrio Postural , Estudos de Tempo e Movimento
14.
Plant Biotechnol J ; 18(8): 1830-1842, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31981296

RESUMO

The cell wall of filamentous fungi, comprised of chitin, polysaccharide and glycoproteins, maintains the integrity of hyphae and protect them from defence responses by potential host plants. Here, we report that one polysaccharide deacetylase of Puccinia striiformis f. sp. tritici (Pst), Pst_13661, suppresses Bax-induced cell death in plants and Pst_13661 is highly induced during early stages of the interaction between wheat and Pst. Importantly, the transgenic wheat expressing the RNA interference (RNAi) construct of Pst_13661 exhibits high resistance to major Pst epidemic races CYR31, CYR32 and CYR33 by inhibiting growth and development of Pst, indicating that Pst_13661 is an available pathogenicity factor and is a potential target for generating broad-spectrum resistance breeding material of wheat. It forms a homo-polymer and has high affinity for chitin and germ tubes of Pst compared with the control. Besides, Pst_13661 suppresses chitin-induced plant defence in plants. Hence, we infer that Pst_13661 may modify the fungal cell wall to prevent recognition by apoplastic surveillance systems in plants. This study opens new approaches for developing durable disease-resistant germplasm by disturbing the growth and development of fungi and develops novel strategies to control crop diseases.


Assuntos
Basidiomycota , Doenças das Plantas , Amidoidrolases , Doenças das Plantas/genética , Imunidade Vegetal/genética , Virulência
15.
Plant Cell Rep ; 39(5): 653-667, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32123996

RESUMO

KEY MESSAGE: The TaMP gene from wheat encodes an α-mannosidase induced by salt stress that functions as negative regulator of salt tolerance in plants. Salt stress significantly affects growth and yield of crop plants. The α-mannosidases function in protein folding, trafficking, and endoplasmic reticulum-associated degradation in eukaryotic cells, and they are involved in abiotic stress tolerance in plants. Previously, we identified the α-mannosidase gene TaMP in wheat (Triticum aestivum). In this study, we investigated the function of TaMP in salt stress tolerance. TaMP expression was induced in wheat leaves by salt, drought, abscisic acid, and H2O2 treatments. Overexpressing TaMP in Brachypodium distachyon was associated with a salt-sensitive phenotype. Under salt stress, the overexpressing plants had reduced height, delayed growth status, low photosynthetic rate, decreased survival rate, and diminished yield. Moreover, the overexpression of TaMP aggravated the tendency for ions to become toxic under salt stress by significantly affecting the Na+ and K+ contents in cells. In addition, TaMP could negatively regulate salt tolerance by affecting the antioxidant enzyme system capacity and increasing the reactive oxygen species accumulation. Our study was helpful to understand the underlying physiological and molecular mechanisms of salt stress tolerance in plants.


Assuntos
Brachypodium/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Tolerância ao Sal/genética , Triticum/enzimologia , alfa-Manosidase/metabolismo , Ácido Abscísico/farmacologia , Antioxidantes/metabolismo , Brachypodium/efeitos dos fármacos , Brachypodium/genética , Brachypodium/fisiologia , Núcleo Celular/genética , Núcleo Celular/metabolismo , Secas , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Potássio/análise , Potássio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sódio/análise , Sódio/metabolismo , Sódio/farmacologia , Triticum/genética , Regulação para Cima , alfa-Manosidase/genética
16.
Angew Chem Int Ed Engl ; 59(26): 10421-10425, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32187790

RESUMO

An atom-economic approach that has an unprecedented high selectivity for the synthesis of lactic acid (LA) based on a catalytic dehydrogenative cross-coupling by using inexpensive bulk ethylene glycol and methanol is described. This method relies on the synthesis and utilization of a novel iridium catalyst bearing three N-heterocyclic carbenes derived from 1,3-dimethylbenzimidazolium salts, and exhibits outstanding activity in the production of LA [turnover frequency (TOF) up to 3660 h-1 ] owing to an elegant metal-ligand cooperation.

17.
Angew Chem Int Ed Engl ; 59(33): 13871-13878, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32385924

RESUMO

The global demand for lactic acid (LA) is increasing due to its successful application as monomer for the manufacture of bioplastics. Although N-heterocyclic carbene (NHC) iridium complexes are promising molecular catalysts for LA synthesis, their instabilities have hindered their utilization especially in commercial applications. Here, we report that a porous self-supported NHC-iridium coordination polymer can efficiently prevent the clusterization of corresponding NHC-Ir molecules and can function as a solid molecular recyclable catalyst for dehydrogenation of bio-polyols to form LA with excellent activity (97 %) and selectivity (>99 %). A turnover number of up to 5700 could be achieved in a single batch, due to the synergistic participation of the Ba2+ and hydroxide ions, as well as the blockage of unwanted pathways by adding methanol. Our findings demonstrate a potential route for the industrial production of LA from cheap and abundant bio-polyols, including sorbitol.


Assuntos
Ácido Láctico/química , Polímeros/química , Catálise , Complexos de Coordenação/química , Hidrogenação , Oxirredução
18.
Biochem Biophys Res Commun ; 510(1): 1-7, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30683315

RESUMO

Nicotine, the main toxic substance in cigarette smoke, significantly reduced the differentiation and maturation ratio of Leydig cell in murine testes. To investigate the underlying mechanism, C57BL/6J mice were divided into control (CT) and nicotine treated (NT) groups. Next generation RNA sequencing and bio-informatics analysis were carried out to analysis the effects of nicotine on the RNA profile of Leydig cells. Expression level of 7 pathways remarkably changed after nicotine treatment. As the positive regulating pathway of Leydig cell differentiation, Hedgehog signaling pathway was found among these pathways. PTCH1 and ß-TrCP were down-regulated in nicotine treated mice Leydig cells, while GSK3ß, Gli2 and Gli2 fragments increased significantly. Nicotine stimulated the destabilization of Gli2 via ß-TrCP induced ubiquitination and degradation. Gli2 was phosphorylated by up-expressed GSK3ß during this process. Destabilization of Gli2 reduced the activation rate of target genes of Hedgehog signaling pathway such as Ptch1. The differentiation of Leydig cell positively regulated by Hh pathway was thus inhibited by nicotine exposure. Consequently, the male reproduction process powered by Leydic cell-mediated androgen secretion was thus influenced. In conclusion, we find that nicotine inhibits murine Leydig cell differentiation and maturation via regulating Hedgehog signal pathway.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proteínas Hedgehog/metabolismo , Células Intersticiais do Testículo/patologia , Nicotina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Reprodução/efeitos dos fármacos
19.
Theor Appl Genet ; 132(8): 2413-2423, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31209536

RESUMO

KEY MESSAGE: Plant male sterility is a valuable trait in breeding and hybrid seed production. The barley male-sterility gene msg26 was mapped to a 0.02-cM region that anchors to a 506-kb low-quality assembly between two cleaved amplified polymorphic sequence (CAPS) markers, SP1M14 and SP1M49. The barley gene HORVU4Hr1G074840, which encodes a putative cytochrome P450 CYP704B protein, appears to be a strong candidate for the MSG26 trait. Barley (Hordeum vulgare L.) is an important cereal crop worldwide. Traditional breeding in barley is time-consuming and labor-intensive. The use of male-sterile genotypes may significantly improve the efficacy of hybrid breeding and seed production. The barley accession 'GSHO745' is a spontaneous male-sterile mutant from the barley variety, 'Unitan'. The male sterility in 'GSHO745' is controlled by the recessive gene, msg26 (originally named as ms-u). We revealed that the barley plants homozygous for msg26 proceeded normally through Meiosis II until the tetrad stage, but became fully defective in the late uninucleate microspores and developed pollen-less anthers. Using seven barley F2 populations, we mapped MSG26 to a 0.02-cM region that anchored to a 506-kb low-quality assembly between two cleaved amplified polymorphic sequence markers, SP1M14 and SP1M49. The HORVU4Hr1G074840 gene that encodes a putative cytochrome P450 protein (CYP704B) was identified as the most plausible candidate for MSG26. First, HORVU4Hr1G074840 is located in a collinear region of the rice CYP704B2 and the maize CYP704B1. Both of these genes are essential for male gamete production. Second, the male-sterile allele of HORVU4Hr1G074840 in GSHO745 contained a 4-bp deletion in the last exon. The resulting frame shift causes a Gly436Gln substitution, scrambles the sequence of the remainder of the protein, and forms a new termination site at the 70th triplet of the shifted reading frame. We thus called the variant protein CYP704B:p.G436Qfs*70. Third, the barley HORVU4Hr1G074840 gene was specifically expressed in anthers. Altogether, HORVU4Hr1G074840 represents a strong candidate for MSG26 in barley.


Assuntos
Flores/genética , Genes de Plantas , Hordeum/genética , Infertilidade das Plantas/genética , Proteínas de Plantas/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Regulação da Expressão Gênica de Plantas , Loci Gênicos , Homozigoto , Especificidade de Órgãos/genética , Proteínas de Plantas/metabolismo , Triticum/genética
20.
Plant J ; 89(5): 1042-1054, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27775877

RESUMO

Cowpea (Vigna unguiculata L. Walp.) is a legume crop that is resilient to hot and drought-prone climates, and a primary source of protein in sub-Saharan Africa and other parts of the developing world. However, genome resources for cowpea have lagged behind most other major crops. Here we describe foundational genome resources and their application to the analysis of germplasm currently in use in West African breeding programs. Resources developed from the African cultivar IT97K-499-35 include a whole-genome shotgun (WGS) assembly, a bacterial artificial chromosome (BAC) physical map, and assembled sequences from 4355 BACs. These resources and WGS sequences of an additional 36 diverse cowpea accessions supported the development of a genotyping assay for 51 128 SNPs, which was then applied to five bi-parental RIL populations to produce a consensus genetic map containing 37 372 SNPs. This genetic map enabled the anchoring of 100 Mb of WGS and 420 Mb of BAC sequences, an exploration of genetic diversity along each linkage group, and clarification of macrosynteny between cowpea and common bean. The SNP assay enabled a diversity analysis of materials from West African breeding programs. Two major subpopulations exist within those materials, one of which has significant parentage from South and East Africa and more diversity. There are genomic regions of high differentiation between subpopulations, one of which coincides with a cluster of nodulin genes. The new resources and knowledge help to define goals and accelerate the breeding of improved varieties to address food security issues related to limited-input small-holder farming and climate stress.


Assuntos
Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Vigna/genética , Vigna/fisiologia , Cromossomos Artificiais Bacterianos , Cromossomos de Plantas/genética , Clima , Abastecimento de Alimentos , Genoma de Planta/genética , Genótipo
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