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1.
J Agric Food Chem ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177757

RESUMO

As a kind of obligate biotrophic fungus, Puccinia striiformis f. sp. tritici (Pst) secretes vast effectors via haustoria to host cells during the infection to inhibit host defense responses and promote fungal invasion. In this study, based on the completion of genome sequencing and haustorial transcriptome sequencing of Pst, we identified a Pst effector (Hasp155) that is significantly induced in the early stage of Pst infection to wheat. The 18 N-terminal amino acids of Hasp155 encoded a signal peptide with a secretory function. Transient expression of Hasp155 in Nicotiana benthamiana inhibited Bax-induced cell death as well as chitin-triggered callose deposition and defense-related gene expression. Moreover, delivery of the Hasp155 protein into wheat cells via type three secretion systems (TTSS) led to reduced plant immunity to nonpathogenic bacteria and to the avirulent Pst race with decreased H2O2 accumulation and promoted Pst development. Furthermore, transgenic overexpression of Hasp155 significantly renders wheat resistance susceptible, resulting in a decreased defense response and increased Pst pathogenicity. Overall, these results indicate that Hasp155 is an important effector of Pst pathogenicity by suppressing plant immunity.

2.
Bioresour Technol ; 406: 131062, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38964514

RESUMO

Acquiring lipid-producing strains of Saccharomyces cerevisiae is necessary for producing high-value palmitoleic acid. This study sought to generate oleaginous S. cerevisiae mutants through a combination of zeocin mutagenesis and fluorescence-activated cell sorting, and then to identify key mutations responsible for enhanced lipid accumulation by multi-omics sequencing. Following three consecutive rounds of mutagenesis and sorting, a mutant, MU310, with the lipid content of 44%, was successfully obtained. Transcriptome and targeted metabolome analyses revealed that a coordinated response involving fatty acid precursor biosynthesis, nitrogen metabolism, pentose phosphate pathway, ethanol conversion, amino acid metabolism and fatty acid ß-oxidation was crucial for promoting lipid accumulation. The carbon fluxes of acetyl-CoA and NADPH in lipid biosynthesis were boosted in these pathways. Certain transcriptional regulators may also play significant roles in modulating lipid biosynthesis. Results of this study provide high-quality resource for palmitoleic acid production and deepen the understanding of lipid synthesis in yeast.


Assuntos
Lipídeos , Mutagênese , Saccharomyces cerevisiae , Ácidos Graxos/metabolismo , Ácidos Graxos Monoinsaturados , Citometria de Fluxo , Metabolismo dos Lipídeos , Lipídeos/biossíntese , Metaboloma , Multiômica , Mutação , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Transcriptoma/genética
3.
Stress Biol ; 4(1): 32, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38945963

RESUMO

Protein phosphorylation plays an important role in immune signaling transduction in plant resistance to pathogens. Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), severely devastates wheat production. Nonetheless, the molecular mechanism of wheat resistance to stripe rust remains limited. In this study, quantitative phosphoproteomics was employed to investigate the protein phosphorylation changes in wheat challenged by Pst. A total of 1537 and 2470 differentially accumulated phosphoproteins (DAPs) were identified from four early infection stage (6, 12, 18 and 24 h post-inoculation) in incompatible and compatible wheat-Pst interactions respectively. KEGG analysis revealed that Oxidative Phosphorylation, Phosphatidylinositol Signaling, and MAPK signaling processes are distinctively enriched in incompatible interaction, while Biosynthesis of secondary metabolites and RNA degradation process were significantly enriched in compatible interactions. In particular, abundant changes in phosphorylation levels of chloroplast proteins were identified, suggesting the regulatory role of photosynthesis in wheat-Pst interaction, which is further emphasized by protein-protein interaction (PPI) network analysis. Motif-x analysis identified [xxxxSPxxxx] motif, likely phosphorylation sites for defensive response-related kinases, and a new [xxxxSSxxxx] motif significantly enriched in incompatible interaction. The results shed light on the early phosphorylation events contributing to wheat resistance against Pst. Moreover, our study demonstrated that the phosphorylation levels of Nucleoside diphosphate kinase TaNAPK1 are upregulated at 12 hpi with CYR23 and at 24 hpi with CYR31. Transient silencing of TaNAPK1 was able to attenuate wheat resistance to CYR23 and CYR31. Our study provides new insights into the mechanisms underlying Pst-wheat interactions and may provide database to find potential targets for the development of new resistant varieties.

4.
Bull Environ Contam Toxicol ; 112(2): 33, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38342847

RESUMO

Abundant iron and sulfate resources are present in acid mine drainage. The synthesis of schwertmannite from AMD rich in iron and sulfate could achieve the dual objectives of resource recovery and wastewater purification. However, schwertmannite cannot emerge spontaneously due to the Gibbs free energy greater than 0. This results in the iron and sulfate in AMD only being able to use the energy generated by oxidation in the coupling reaction to promote the formation of minerals, but this only achieved partial mineralization, which limited the remediation of AMD through mineralization. In order to clarify the mechanism of iron and sulfate removal by the formation of schwertmannite in AMD, kinetic and thermodynamic parameters were crucial. This work used H2O2 oxidation of Fe2+ as a coupling reaction to promote the formation of schwertmannite from 64.4% of iron and 15.7% of sulfate in AMD, and determined that 99.7% of the iron and 89.9% of sulfate were immobilized in the schwertmannite structural, and only a small fraction was immobilized by the adsorption of schwertmannite, both of which were consistent with second-order kinetics models. The thermodynamic data suggested that reducing the concentration of excess sulfate ions or increasing the energy of the system may allow more iron and sulfate to be immobilized by forming schwertmannite. Experimental verification using the reaction of potassium bicarbonate with the acidity in solution to increase the energy in the system showed that the addition of potassium bicarbonate effectively promoted the formation of schwertmannite from Fe3+ and SO42-. It provided a theoretical and research basis for the direct synthesis of schwertmannite from Fe3+ and SO42- rich AMD for the removal of contaminants from water and the recovery of valuable resources.


Assuntos
Bicarbonatos , Compostos de Ferro , Ferro , Compostos de Potássio , Adsorção , Peróxido de Hidrogênio , Compostos de Ferro/química , Oxirredução , Sulfatos/química , Concentração de Íons de Hidrogênio
5.
Bioorg Med Chem Lett ; 101: 129648, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38331226

RESUMO

In the treatment of non-small cell lung cancer (NSCLC), acquired drug resistance is a major factor that affects the efficacy of third-generation epidermal growth factor receptor (EGFR) inhibitors like Osimertinib. To overcome the L858R/T790M/C797S mutation, taking the Brigatinib as the positive control, two classes of 20 target compounds were designed and synthesized with 2-phenylaminopyrimidine as the core structure on the basis of summarizing the structure-activity relationship (SAR), following the basic principles of drug design. Representative compound I-10 potently inhibited EGFRL858R/T790M/C797S with an IC50 value of 33.26 nM and suppressed Ba/F3-EGFRL858R/T790M/C797S cells with an IC50 value of 106.4 nM, which is 5-fold more potent than Brigatinib. Besides, the compound exhibited an inhibition rate of less than 50 % against wild-type cell (NCI-H838), which reflected its toxicity or selectivity. Furthermore, this work serves as a foundation for future studies on EGFR inhibitors.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Compostos Organofosforados , Pirimidinas , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Receptores ErbB , Mutação , Inibidores de Proteínas Quinases/química , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral
6.
J Agric Food Chem ; 71(50): 19986-19999, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38063491

RESUMO

Berberine bridge enzymes (BBEs), functioning as carbonate oxidases, enhance disease resistance in Arabidopsis and tobacco. However, the understanding of BBEs' role in monocots against pathogens remains limited. This study identified 81 TaBBEs with FAD_binding_4 and BBE domains. Phylogenetic analysis revealed a separation of the BBE gene family between monocots and dicots. Notably, RNA-seq showed TaBBE64's significant induction by both pathogen-associated molecular pattern treatment and Puccinia striiformis f. sp. tritici (Pst) infection at early stages. Subcellular localization revealed TaBBE64 at the cytoplasmic membrane. Knocking down TaBBE64 compromised wheat's Pst resistance, reducing reactive oxygen species and promoting fungal growth, confirming its positive role. Molecular docking and enzyme activity assays confirmed TaBBE64's glucose oxidation to produce H2O2. Since Pst relies on living wheat cells for carbohydrate absorption, TaBBE64's promotion of glucose oxidation limits fungal growth and resists pathogen infection. This study sheds light on BBEs' role in wheat resistance against biotrophic fungi.


Assuntos
Basidiomycota , Triticum , Triticum/microbiologia , Filogenia , Peróxido de Hidrogênio , Simulação de Acoplamento Molecular , Glucose , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Basidiomycota/genética
7.
Mol Plant ; 16(10): 1564-1589, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37671604

RESUMO

Wheat (Triticum aestivum) is a staple food for about 40% of the world's population. As the global population has grown and living standards improved, high yield and improved nutritional quality have become the main targets for wheat breeding. However, wheat production has been compromised by global warming through the more frequent occurrence of extreme temperature events, which have increased water scarcity, aggravated soil salinization, caused plants to be more vulnerable to diseases, and directly reduced plant fertility and suppressed yield. One promising option to address these challenges is the genetic improvement of wheat for enhanced resistance to environmental stress. Several decades of progress in genomics and genetic engineering has tremendously advanced our understanding of the molecular and genetic mechanisms underlying abiotic and biotic stress responses in wheat. These advances have heralded what might be considered a "golden age" of functional genomics for the genetic improvement of wheat. Here, we summarize the current knowledge on the molecular and genetic basis of wheat resistance to abiotic and biotic stresses, including the QTLs/genes involved, their functional and regulatory mechanisms, and strategies for genetic modification of wheat for improved stress resistance. In addition, we also provide perspectives on some key challenges that need to be addressed.


Assuntos
Melhoramento Vegetal , Triticum , Triticum/genética , Mudança Climática , Plantas , Estresse Fisiológico/genética
8.
Cell Commun Signal ; 21(1): 268, 2023 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-37777801

RESUMO

Due to the complexity and incomplete understanding of the crosstalk between liver and adipose tissue, especially the processes of hepatic lipogenesis and adipogenic differentiation, there are currently no effective drugs for the treatment of nonalcoholic fatty liver disease (NAFLD). Stearoyl-coenzyme A desaturase 1 (SCD1), which is abundantly expressed in liver and adipose tissue, may mediate the cross-talk between liver and adipose tissue. Thus, it is essential to develop specific SCD1 inhibitors that target the liver-adipose axis. Herein, we identified a novel SCD1 inhibitor, E6446, through a high-throughput virtual screen. E6646 significantly inhibited adipogenic differentiation and hepatic lipogenesis via SCD1-ATF3 signaling. The SPR results showed that E6446 had a strong interaction ability with SCD1 (KD:4.61 µM). Additionally, E6646 significantly decreased hepatic steatosis, hepatic lipid droplet accumulation and insulin resistance in high-fat diet (HFD)-fed mice. Taken together, our findings not only suggest that E6446 can serve as a new, safe and highly effective anti-NAFLD agent for future clinical use but also provide a molecular basis for the future development of SCD1 inhibitors that inhibit both adipogenic differentiation and hepatic lipogenesis. Video Abstract.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo , Obesidade/metabolismo , Lipogênese , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL
9.
Huan Jing Ke Xue ; 44(9): 4874-4883, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699806

RESUMO

As one of the famous karst springs in Shanxi Province, the Gudui spring is the only medium-low temperature hot spring, with a long history of development and a rich cultural accumulation. The karst groundwater in the Gudui spring catchment was taken as the research object. Through systematic sample collection and isotope analysis, hydrochemistry (Durov map, ion ratio, Gibbs map, and hydrogen and oxygen isotope) methods were comprehensively used to analyze groundwater hydrochemistry and groundwater system runoff characteristics. The87Sr/86Sr value of karst groundwater in the Gudui spring catchment was 0.709 to 0.717, and the Mg/(Mg+Ca) value was 0.27 to 0.74. By analyzing the Sr isotope composition and Mg/(Mg+Ca) and 1/Sr variation characteristics, it was concluded that the karst groundwater in the Gudui spring catchment was a mixture of deep hot water and shallow cold water. The karst water subsystem of Nanliang spring presented the characteristics of carbonate stratum runoff. The karst water subsystem of Fuling Mountain Gaoxian Haitou spring and the deep circulation subsystem of Houma Basin exhibited the runoff characteristics of carbonate rock and igneous rock strata. The karst water subsystem of Taiershan Jiuyuanshan Gudui spring presented the runoff characteristics of carbonate rock and ancient silicoaluminate strata. The δ18O value in karst groundwater of Guodui spring area ranged from -11.46‰ to -7.81‰, and the average value was -10.08‰. The range of the δD value was -83.7‰ to -60.8‰, and the average value was -73.6‰. This showed that karst groundwater in the spring area was the result of mixing of various types of water. Through comparative analysis of hydrogen and oxygen isotopes of 2014 and 2021 sampling points at the same location, it was concluded that the change in water samples at the Guduiquan resulted from the gradual accumulation of water supplied by Sanquan Reservoir. The change in Sanquan Reservoir was due to the influence of Yellow River diversion. The karst groundwater in the spring area were characterized by large calcium ion, magnesium ion, and sodium ion values; a small potassium ion value; a large sulfate value; and a small chloride value. The hydrochemical types of karst groundwater in Gudui spring catchment could be divided into SO4-Na, SO4-Ca, HCO3-Na, HCO3-Mg, HCO3-Ca, and Cl-Na. The hydrochemical types of karst groundwater showed evident hydrochemical composition zoning from HCO3-Ca·Mg→HCO3·SO4-Ca·Mg→SO4·HCO3-Na·Ca→SO4·Cl-Na·Ca. According to the comprehensive analysis of hydrochemical isotope and hydrogeological conditions, the karst water subsystem of Nanliang spring was primarily recharged by rainfall infiltration in the exposed limestone area and river infiltration, and its karst groundwater was recharged by runoff from south to north to the karst water subsystem of Fuling Mountain Gaoxian Haitou spring and the deep circulation subsystem of Houma Basin. The karst water subsystem of Taier Jiuyuan Mountain Gudui spring received rainfall infiltration supplement and upstream runoff supplement from the exposed limestone area. Its karst groundwater flowed from north to south and received the supply of Sanquan Reservoir from Yellow River water in the natural discharge area of Gudui spring.

10.
Bioorg Med Chem Lett ; 88: 129284, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060933

RESUMO

Cyclin-dependent kinase 2 (CDK2) is considered as an important target in the research of antitumor drugs. Taking the CDK2/4/6 inhibitor Ebvaciclib as the positive control and an in-house library compound (23) as the lead compound, three classes of 30 target compounds with pteridin-7(8H)-one as the core structure were designed to establish structure-activity relationships (SAR). In general, SAR of pteridin-7(8H)-one CDK2 inhibitors is systematically described in this paper, resulting in the discovery of two compounds (KII-17 and KII-21) with further research value. After the above compounds were tested for CDK2/4/6 kinase selectivity, we found that compound KII-21 was about 3 and 4 times more selective to CDK2-cyclinE2 than CDK4-cyclinD1 and CDK6-cyclinD3, respectively. This work also provides a reference basis for the subsequent research on CDK2 inhibitors.


Assuntos
Antineoplásicos , Inibidores de Proteínas Quinases , Antineoplásicos/química , Quinase 2 Dependente de Ciclina , Quinase 4 Dependente de Ciclina , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade
11.
Int J Mol Sci ; 24(7)2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-37047410

RESUMO

Plant cell surface-localized receptor-like kinases (RLKs) recognize invading pathogens and transduce the immune signals inside host cells, subsequently triggering immune responses to fight off pathogen invasion. Nonetheless, our understanding of the role of RLKs in wheat resistance to the biotrophic fungus Puccinia striiformis f. sp. tritici (Pst) remains limited. During the differentially expressed genes in Pst infected wheat leaves, a Leucine-repeat receptor-like kinase (LRR-RLK) gene TaBIR1 was significantly upregulated in the incompatible wheat-Pst interaction. qRT-PCR verified that TaBIR1 is induced at the early infection stage of Pst. The transient expression of TaBIR1-GFP protein in N. bentamiana cells and wheat mesophyll protoplasts revealed its plasma membrane location. The knockdown of TaBIR1 expression by VIGS (virus induced gene silencing) declined wheat resistance to stripe rust, resulting in reduced reactive oxygen species (ROS) production, callose deposition, and transcripts of pathogenesis-related genes TaPR1 and TaPR2, along with increased Pst infection area. Ectopic overexpression of TaBIR1 in N. benthamiana triggered constitutive immune responses with significant cell death, callose accumulation, and ROS production. Moreover, TaBIR1 triggered immunity is dependent on NbBAK1, the silencing of which significantly attenuated the defense response triggered by TaBIR1. TaBIR1 interacted with the NbBAK1 homologues in wheat, co-receptor TaSERK2 and TaSERK5, the transient expression of which could restore the impaired defense due to NbBAK1 silencing. Taken together, TaBIR1 is a cell surface RLK that contributes to wheat stripe rust resistance, probably as a positive regulator of plant immunity in a BAK1-dependent manner.


Assuntos
Basidiomycota , Triticum , Triticum/microbiologia , Leucina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Imunidade Inata , Basidiomycota/genética , Doenças das Plantas/microbiologia
12.
Bioorg Med Chem Lett ; 88: 129265, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37011767

RESUMO

Son of sevenless 1 (SOS1) is a vital guanine nucleotide exchange factor (GEFs) that activates rat sarcoma (Ras) protein in cells. SOS1 inhibitors can effectively inhibit the expression of downstream signaling pathways by blocking the interaction between SOS1 and Ras protein. Here, we designed and synthesized a series of quinazoline-based compounds, and conducted subsequent evaluations of their biological activities. Among them, the comparable compounds I-2 (IC50 = 20 nM, against SOS1) I-5 (IC50 = 18 nM, against SOS1) and I-10 (IC50 = 8.5 nM, against SOS1) have kinase activity equivalent to BAY-293 (IC50 = 6.6 nM, against SOS1), and I-10 also has cell activity equivalent to BAY-293, providing a theoretical reference for subsequent related researches on SOS1 inhibitors.


Assuntos
Núcleo Familiar , Transdução de Sinais , Proteínas Son Of Sevenless , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fosforilação , Proteínas Son Of Sevenless/antagonistas & inibidores , Quinazolinas/química , Quinazolinas/farmacologia
13.
Br J Pharmacol ; 180(17): 2266-2279, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37005734

RESUMO

BACKGROUND AND PURPOSE: High-fat diet (HFD) induces dysregulated pathways in coronary artery endothelial cells (CAECs), which leads to altered regulation of vascular tone, tissue perfusion and increases the risk of coronary artery diseases. Ca2+ -activated K+ (KCa ) channels are known to be associated with transient receptor potential (TRP) channels, which are important for regulating endothelial function. But how TRPV4 channels interacts with KCa channels in regulating coronary vascular tone in HFD mice requires further exploration. EXPERIMENTAL APPROACH: TRPV4 channel activity was assessed by fluorescent Ca2+ imaging. Interactions between TRPV4 and KCa 3.1 channels were verified by co-immunoprecipitation and immunofluorescence resonance energy transfer (FRET), and their binding site was found by site-directed mutagenesis. Endothelium-specific TRPV4 knockout (TRPV4EC -/- ) mice were used to study the effect of the interactions between TRPV4-KCa 3.1 channels on coronary vascular tone. Coronary blood flow was measured by Doppler ultrasound device. KEY RESULTS: TRPV4 channels were involved in regulating coronary vascular tone, through coupling with a Ca2+ -sensitive K+ channel (KCa 3.1) in CAECs, affecting vasodilation and coronary blood flow. In mice fed a HFD diet, the coupling was damaged by a high concentration of plasma 1-heptadecanoyl-2-hydroxy-sn-glycero-3-phosphocholine. Using a bridging approach, we then identified folic acid as an effective drug to repair the uncoupled TRPV4-KCa 3.1 channels and to improve coronary arterial function. CONCLUSION AND IMPLICATIONS: Our data highlight the importance of coupling between TRPV4 and KCa 3.1 channels in the regulation of coronary vascular tone and provide a novel strategy for developing new drugs to reduce the incidence of cardiovascular events.


Assuntos
Vasos Coronários , Canais de Potencial de Receptor Transitório , Camundongos , Animais , Vasos Coronários/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Células Endoteliais/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Vasodilatação , Endotélio/metabolismo , Endotélio Vascular
14.
J Integr Plant Biol ; 65(1): 249-264, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36181397

RESUMO

The obligate biotrophic fungus Puccinia striiformis f. sp. tritici (Pst) employs virulence effectors to disturb host immunity and causes devastating stripe rust disease. However, our understanding of how Pst effectors regulate host defense responses remains limited. In this study, we determined that the Pst effector Hasp98, which is highly expressed in Pst haustoria, inhibits plant immune responses triggered by flg22 or nonpathogenic bacteria. Overexpression of Hasp98 in wheat (Triticum aestivum) suppressed avirulent Pst-triggered immunity, leading to decreased H2 O2 accumulation and promoting P. striiformis infection, whereas stable silencing of Hasp98 impaired P. striiformis pathogenicity. Hasp98 interacts with the wheat mitogen-activated protein kinase TaMAPK4, a positive regulator of plant resistance to stripe rust. The conserved TEY motif of TaMAPK4 is important for its kinase activity, which is required for the resistance function. We demonstrate that Hasp98 inhibits the kinase activity of TaMAPK4 and that the stable silencing of TaMAPK4 compromises wheat resistance against P. striiformis. These results suggest that Hasp98 acts as a virulence effector to interfere with the MAPK signaling pathway in wheat, thereby promoting P. striiformis infection.


Assuntos
Basidiomycota , Triticum , Virulência/fisiologia , Triticum/metabolismo , Basidiomycota/fisiologia , Puccinia , Doenças das Plantas/microbiologia
15.
J Am Med Inform Assoc ; 30(3): 438-446, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36478240

RESUMO

OBJECTIVES: To develop an unbiased objective for learning automatic coding algorithms from clinical records annotated with only partial relevant International Classification of Diseases codes, as annotation noise in undercoded clinical records used as training data can mislead the learning process of deep neural networks. MATERIALS AND METHODS: We use Medical Information Mart for Intensive Care III as our dataset. We employ positive-unlabeled learning to achieve unbiased loss estimation, which is free of misleading training signal. We then utilize reweighting mechanism to compensate for the imbalance between positive and negative samples. To further close the performance gap caused by poor quality annotation, we integrate the supervision provided by the automatic annotation tool Medical Concept Annotation Toolkit which can ease the heavy burden of manual validation. RESULTS: Our benchmarking results show that positive-unlabeled learning with reweighting outperforms competitive baseline methods over a range of missing label ratios. Integrating supervision provided by annotation tool further boosted the performance. DISCUSSION: Considering the annotation noise and severe imbalance, unbiased loss estimation and reweighting mechanism are both important for learning from undercoded clinical records. Unbiased loss requires the estimation of false negative ratios and estimation through trained models is practical and competitive. CONCLUSIONS: The combination of positive-unlabeled learning with reweighting and supervision provided by the annotation tool is a promising solution to learn from undercoded clinical records.


Assuntos
Registros Eletrônicos de Saúde , Classificação Internacional de Doenças , Humanos , Redes Neurais de Computação , Algoritmos , Cuidados Críticos
16.
Plants (Basel) ; 13(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38202402

RESUMO

Puccinia striiformis f. sp. tritici is an obligate biotrophic fungus that causes destructive stripe rust disease in wheat. During infection, Pst secretes virulence effectors via a specific infection structure-the haustorium-inside host cells to disturb host immunity and promote fungal colonization and expansion. Hence, the identification and functional analyses of Pst effectors are of great significance in deciphering the Pst pathogenicity mechanism. Here, we identified one candidate Pst effector Pst_9302 that could suppress Bax-triggered cell death in Nicotiana benthamiana. qRT-PCR analyses showed that the transcript levels of Pst_9302 were highly increased during the early infection stages of Pst. The transient expression of Pst_9302 in wheat via the type-three secretion system (T3SS) significantly inhibited the callose deposition induced by Pseudomonas syringae EtHAn. During wheat-Pst interaction, Pst_9302 overexpression suppressed reactive oxygen species (ROS) accumulation and cell death caused by the avirulent Pst race CYR23. The host-induced gene silencing (HIGS) of Pst_9302 resulted in decreased Pst pathogenicity with reduced infection area. The results suggest that Pst_9302 plays a virulence role in suppressing plant immunity and promoting Pst pathogenicity. Moreover, wheat voltage-dependent anion channel 1 protein (TaVDAC1) was identified as candidate Pst_9302-interacting proteins by yeast two-hybrid (Y2H) screening. Pull-down assays using the His-Pst_9302 and GST-TaVDAC1 protein verified their interactions. These results suggest that Pst_9302 may modulate wheat TaVDAC1 to regulate plant immunity.

17.
Huan Jing Ke Xue ; 43(10): 4440-4448, 2022 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-36224130

RESUMO

The Fenhe River Basin is the mother river of Shanxi Province. Due to the over-exploitation of water resources and the impact of social and economic development, the ecological environment has deteriorated. After a series of treatment and protection measures, the water quality has since been improved. Mathematical statistics, Piper diagrams, Gibbs model, hydrogen and oxygen isotopes, and other methods were used to analyze the characteristics and sources of hydrochemistry in the surface water of the Fenhe River basin, which revealed the evolution process of surface water quality of the Fenhe River basin. The results showed that the content of the main hydrochemical components in the main stream surface water of Fenhe River basin increased gradually along the runoff path. The hydrochemical types of surface water of Fenhe River basin were mainly HCO3·SO4·Cl-Ca·Na·Mg and SO4·HCO3·Cl-Ca·Na·Mg. There were great differences in hydrochemical components of tributaries and karst water in the basin. There were also great differences in hydrochemical components of tributaries in the basin. The hydrochemical types of surface water of karst water were mainly SO4·HCO3-Ca·Mg. The hydrochemical composition of surface water in Fenhe River basin was mainly affected by rock weathering and evaporation crystallization, whereas rainfall had little effect. Na+ and K+ mainly came from the dissolution of evaporated salt rocks with Na in the surrounding loess. Ca2+, Mg2+, and HCO3- mainly came from the dissolution of carbonate rocks. SO42- may have also come from the dissolution of sulfide minerals in the loess layer around Fenhe River in addition to the dissolution of gypsum. The values of δD and δ18O of Fenhe River surface water were gradually enriched from upstream to downstream. The characteristics of hydrogen and oxygen isotopes further showed that the surface water was mainly affected by evaporation. The results of this study can provide evidence for ecological restoration and protection and ecological civilization construction in the Fenhe River basin.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Sulfato de Cálcio , Carbonatos , Monitoramento Ambiental/métodos , Água Subterrânea/química , Hidrogênio , Minerais , Isótopos de Oxigênio , Sulfetos , Poluentes Químicos da Água/análise , Qualidade da Água
18.
Cell ; 185(16): 2961-2974.e19, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35839760

RESUMO

Wheat crops are frequently devastated by pandemic stripe rust caused by Puccinia striiformis f. sp. tritici (Pst). Here, we identify and characterize a wheat receptor-like cytoplasmic kinase gene, TaPsIPK1, that confers susceptibility to this pathogen. PsSpg1, a secreted fungal effector vital for Pst virulence, can bind TaPsIPK1, enhance its kinase activity, and promote its nuclear localization, where it phosphorylates the transcription factor TaCBF1d for gene regulation. The phosphorylation of TaCBF1d switches its transcriptional activity on the downstream genes. CRISPR-Cas9 inactivation of TaPsIPK1 in wheat confers broad-spectrum resistance against Pst without impacting important agronomic traits in two years of field tests. The disruption of TaPsIPK1 leads to immune priming without constitutive activation of defense responses. Taken together, TaPsIPK1 is a susceptibility gene known to be targeted by rust effectors, and it has great potential for developing durable resistance against rust by genetic modifications.


Assuntos
Basidiomycota , Triticum , Basidiomycota/genética , Basidiomycota/metabolismo , Doenças das Plantas , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Triticum/genética , Triticum/metabolismo , Triticum/microbiologia , Virulência/genética
19.
BMC Med Inform Decis Mak ; 22(1): 174, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778708

RESUMO

BACKGROUND: People live a long time in pre-diabetes/early diabetes without a formal diagnosis or management. Heterogeneity of progression coupled with deficiencies in electronic health records related to incomplete data, discrete events, and irregular event intervals make identification of pre-diabetes and critical points of diabetes progression challenging. METHODS: We utilized longitudinal electronic health records of 9298 patients with type 2 diabetes or prediabetes from 2005 to 2016 from a large regional healthcare delivery network in China. We optimized a generative Markov-Bayesian-based model to generate 5000 synthetic illness trajectories. The synthetic data were manually reviewed by endocrinologists. RESULTS: We build an optimized generative progression model for type 2 diabetes using anchor information to reduce the number of parameters learning in the third layer of the model from [Formula: see text] to [Formula: see text], where [Formula: see text] is the number of clinical findings, [Formula: see text] is the number of complications, [Formula: see text] is the number of anchors. Based on this model, we infer the relationships between progression stages, the onset of complication categories, and the associated diagnoses during the whole progression of type 2 diabetes using electronic health records. DISCUSSION: Our findings indicate that 55.3% of single complications and 31.8% of complication patterns could be predicted early and managed appropriately to potentially delay (as it is a progressive disease) or prevented (by lifestyle modifications that keep patient from developing/triggering diabetes in the first place). CONCLUSIONS: The full type 2 diabetes patient trajectories generated by the chronic disease progression model can counter a lack of real-world evidence of desired longitudinal timeframe while facilitating population health management.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Pré-Diabético , Teorema de Bayes , China/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Humanos , Estado Pré-Diabético/complicações , Estado Pré-Diabético/epidemiologia
20.
Cancer Cell Int ; 22(1): 202, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35642041

RESUMO

BACKGROUND: Breast cancer is the most common malignancy affecting women, yet effective targets and related candidate compounds for breast cancer treatment are still lacking. The lipogenic enzyme, stearoyl-CoA desaturase-1 (SCD1), has been considered a potential target for breast cancer treatment. Icaritin (ICT), a prenylflavonoid derivative from the Traditional Chinese Medicine Epimedii Herba, has been reported to exert anticancer effects in various types of cancer. The purpose of the present study was to explore the effect of the new ICT derivative, IC2, targeting SCD1 on breast cancer cells and to explore the specific mechanism. METHODS: Immunohistochemistry and semiquantitative evaluation were performed to detect the expression level of SCD1 in normal and tumor samples. Computer-aided drug design (CADD) technology was used to target SCD1 by molecular docking simulation, and several new ICT derivatives were prepared by conventional chemical synthesis. Cell viability was evaluated by an MTT assay and dead cell staining. SCD1 expression in cancer cells was determined by Western blot and qRT-PCR analyses. The enzymatic activity of SCD1 was evaluated by detecting the conversion rate of [d31] palmitic acid (PA) using Gas chromatography-mass spectrometry (GC-MS). DAPI staining, flow cytometry and Western blot were used to detect cell apoptosis. Mitochondrial membrane potential and reactive oxygen species (ROS) assays were used to determine cell mitochondrial function. Lentiviral transduction was utilized to generate SCD1-overexpressing cell lines. RESULTS: We found that SCD1 was overexpressed and correlated with poor prognosis in breast cancer patients. Among a series of ICT derivatives, in vitro data showed that IC2 potentially inhibited the viability of breast cancer cells, and the mechanistic study revealed that IC2 treatment resulted in ROS activation and cellular apoptosis. We demonstrated that IC2 inhibited SCD1 activity and expression in breast cancer cells in a dose-dependent manner. Moreover, SCD1 overexpression alleviated IC2-induced cytotoxicity and apoptosis in breast cancer cells. CONCLUSIONS: The new ICT derivative, IC2, was developed to induce breast cancer cell apoptosis by inhibiting SCD1, which provides a basis for the development of IC2 as a potential clinical compound for breast cancer treatment.

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