33 research outputs found

    Clustering based Multiple Anchors High-Dimensional Model Representation

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    In this work, a cut high-dimensional model representation (cut-HDMR) expansion based on multiple anchors is constructed via the clustering method. Specifically, a set of random input realizations is drawn from the parameter space and grouped by the centroidal Voronoi tessellation (CVT) method. Then for each cluster, the centroid is set as the reference, thereby the corresponding zeroth-order term can be determined directly. While for non-zero order terms of each cut-HDMR, a set of discrete points is selected for each input component, and the Lagrange interpolation method is applied. For a new input, the cut-HDMR corresponding to the nearest centroid is used to compute its response. Numerical experiments with high-dimensional integral and elliptic stochastic partial differential equation as backgrounds show that the CVT based multiple anchors cut-HDMR can alleviate the negative impact of a single inappropriate anchor point, and has higher accuracy than the average of several expansions

    The Farnesyltransferase β-Subunit Ram1 Regulates Sporisorium scitamineum Mating, Pathogenicity and Cell Wall Integrity

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    The basidiomycetous fungus Sporisorium scitamineum causes a serious sugarcane smut disease in major sugarcane growing areas. Sexual mating is essential for infection to the host; however, its underlying molecular mechanism has not been fully studied. In this study, we identified a conserved farnesyltransferase (FTase) β subunit Ram1 in S. scitamineum. The ram1Δ mutant displayed significantly reduced mating/filamentation, thus of weak pathogenicity to the host cane. The ram1Δ mutant sporidia showed more tolerant toward cell wall stressor Congo red compared to that of the wild-type. Transcriptional profiling showed that Congo red treatment resulted in notable up-regulation of the core genes involving in cell wall integrity pathway in ram1Δ sporidia compared with that of WT, indicating that Ram1 may be involved in cell wall integrity regulation. In yeast the heterodimeric FTase is responsible for post-translational modification of Ras (small G protein) and a-factor (pheromone). We also identified and characterized two conserved Ras proteins, Ras1 and Ras2, respectively, and a MAT-1 pheromone precursor Mfa1. The ras1Δ, ras2Δ and mfa1Δ mutants all displayed reduced mating/filamentation similar as the ram1Δ mutant. However, both ras1Δ and ras2Δ mutants were hypersensitive to Congo red while the mfa1Δ mutant was the same as wild-type. Overall our study displayed that RAM1 plays an essential role in S. scitamineum mating/filamentation, pathogenicity, and cell wall stability

    Peritumoral Microgel Reservoir for Long-Term Light-Controlled Triple-Synergistic Treatment of Osteosarcoma with Single Ultra-Low Dose

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    Local minimally invasive injection of anticancer therapies is a compelling approach to maximize the utilization of drugs and reduce the systemic adverse drug effects. However, the clinical translation is still hampered by many challenges such as short residence time of therapeutic agents and the difficulty in achieving multi-modulation combination therapy. Herein, mesoporous silica-coated gold nanorods (AuNR@SiO2) core-shell nanoparticles are fabricated to facilitate drug loading while rendering them photothermally responsive. Subsequently, AuNR@SiO2 is anchored into a monodisperse photocrosslinkable gelatin (GelMA) microgel through one-step microfluidic technology. Chemotherapeutic drug doxorubicin (DOX) is loaded into AuNR@SiO2 and 5,6-dimethylxanthenone-4-acetic acid (DMXAA) is loaded in the microgel layer. The osteosarcoma targeting ligand alendronate is conjugated to AuNR@SiO2 to improve the tumor targeting. The microgel greatly improves the injectability since they can be dispersed in buffer and the injectability and degradability are adjustable by microfluidics during the fabrication. The drug release can, in turn, be modulated by multi-round light-trigger. Importantly, a single super low drug dose (1 mg kg(-1) DOX with 5 mg kg(-1) DMXAA) with peritumoral injection generates long-term therapeutic effect and significantly inhibited tumor growth in osteosarcoma bearing mice. Therefore, this nanocomposite@microgel system can act as a peritumoral reservoir for long-term effective osteosarcoma treatment

    Neovascularization-directed bionic eye drops for noninvasive renovation of age-related macular degeneration

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    The current treatment of wet age-related macular degeneration (wAMD) relies on monthly intravitreal or intravenously injection of vascular endothelial growth factor (VEGF) inhibitor or photodynamic (PDT) agents to inhibit choroidal neovascularization. However, traumatic local therapy and exogenous long-distance fundus drug delivery often lead to secondary eye damage, low treatment efficiency, and immunogenic inflammation. Herein, inspired by the natural neovascular targeting ability of endogenous low-density lipoproteins (LDL), a noninvasive bionic nano-eye-drop with enhanced ocular penetrability and lesion recognizability is developed for enabling the PDT treatment of wAMD. Verteporfin (VP) as a laser-induced PDT agent is protected inside the hydrophobic core of reconstituted LDL (rLDL) vectors. 5-carboxyfluorescein (FAM) conjugated ste-penetratin (PEN, a transmembrane peptide) is anchored on the surface of the rLDL carrier, which enabled the nanoparticles (PEN-rLDL-VP) to cross the blood-retina barrier to realizing visual therapy. Following instillation, PEN-rLDL-VP can effectively deliver VP into neovascular that overexpress LDL receptors, which can respond to laser-induced PDT. Only with a single dose of the eye-drop and laser-induced PDT, the VEGF and proinflammatory intercellular adhesion molecule-1 (ICAM-1) proteins are significantly down-regulated in vivo, which implicates the neovascular inhibition and inflammation alleviation. This study presents an attractive non-invasive strategy for the PDT of wAMD

    Transcriptome analysis of Sporisorium scitamineum reveals critical environmental signals for fungal sexual mating and filamentous growth

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    BACKGROUND: Sporisorium scitamineum causes the sugarcane smut disease, one of the most serious constraints to global sugarcane production. S. scitamineum possesses a sexual mating system composed of two mating-type loci, a and b locus. We previously identified and deleted the b locus in S. scitamineum, and found that the resultant SsΔMAT-1b mutant was defective in mating and pathogenicity. RESULTS: To further understand the function of b-mating locus, we carried out transcriptome analysis by comparing the transcripts of the mutant strain SsΔMAT-1b, from which the SsbE1 and SsbW1 homeodomain transcription factors have previously been deleted, with those from the wild-type MAT-1 strain. Also the transcripts from SsΔMAT-1b X MAT-2 were compared with those from wild-type MAT-1 X MAT-2 mating. A total of 209 genes were up-regulated (p < 0.05) in the SsΔMAT-1b mutant, compared to the wild-type MAT-1 strain, while 148 genes down-regulated (p < 0.05). In the mixture, 120 genes were up-regulated (p < 0.05) in SsΔMAT-1b X MAT-2, which failed to mate, compared to the wild-type MAT-1 X MAT-2 mating, and 271 genes down-regulated (p < 0.05). By comparing the up- and down-regulated genes in these two sets, it was found that 15 up-regulated and 37 down-regulated genes were common in non-mating haploid and mating mixture, which indeed could be genes regulated by b-locus. Furthermore, GO and KEGG enrichment analysis suggested that carbon metabolism pathway and stress response mediated by Hog1 MAPK signaling pathway were altered in the non-mating sets. CONCLUSIONS: Experimental validation results indicate that the bE/bW heterodimeric transcriptional factor, encoded by the b-locus, could regulate S. scitamineum sexual mating and/or filamentous growth via modulating glucose metabolism and Hog1-mediating oxidative response. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-016-2691-5) contains supplementary material, which is available to authorized users

    Enhancing Sugarcane Growth and Improving Soil Quality by Using a Network-Structured Fertilizer Synergist

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    High usage and low efficiency of fertilizers not only restrict sugarcane production but also destroy the soil environment in China. To solve this problem, a network-structured nanocomposite as a fertilizer synergist (FS) was prepared based on attapulgite (ATP) and polyglutamic acid (PGA). Field demonstrations were conducted from 2020 to 2021. Leaching tests and characterization were used to evaluate the ability of the network structure to control nutrient loss. The effects of FS on sugarcane growth and field soil quality were also investigated. The results showed FS could effectively reduce nitrogen loss by 20.30% and decrease fertilizer usage by at least 20%. Compared to fertilizer with the same nutrition, fertilizer with FS could enhance sugarcane yield and brix by 20.79% and 0.58 percentage points, respectively. Additionally, FS improved the soil physicochemical properties, including reducing the soil bulk density and increasing the contents of nitrogen, phosphorus, potassium, and organic matter. FS also altered the diversity of the bacteria and improved the bacterial richness. Our study shows this FS has a good ability to control nutrient loss, advance sugarcane agronomic traits, and improve soil quality. This work offers an option for the sustainable development of sugarcane through the novel FS

    Kinase Hog1 and Adr1 Opposingly Regulate Haploid Cell Morphology by Controlling Vacuole Size in Sporisorium scitamineum

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    Morphogenesis is a strictly regulated efficient system in eukaryotes for adapting to environmental changes. However, the morphogenesis regulatory mechanism in smut fungi is not clear. This study reports a relationship between MAP kinase Hog1 and cAMP-dependent protein kinase A catalytic subunit (Adr1) for the morphological regulation in the sugarcane pathogen Sporisorium scitamineum. The results demonstrated that MAP kinase Hog1 and cAMP/PKA signaling pathways are essential for the morphological development of S. scitamineum. Interestingly, MAP kinase Hog1 and cAMP/PKA signaling pathways&rsquo; defective mutants exhibit an opposite morphological phenotype. The morphology of cAMP/PKA defective mutants is recovered by deleting the SsHOG1 gene. However, MAP kinase Hog1 and cAMP-dependent protein kinase catalytic subunit Adr1 do not interfere with each other. Further investigations showed that kinase Hog1 and Adr1 antagonistically regulates the vacuolar size, which contributes to the cell size and determines the cellular elongation rates. Kinase Hog1 and Adr1 also antagonistically balanced the cell wall integrity and permeability. Taken together, kinase Hog1- and Adr1-based opposing morphogenesis regulation of S. scitamineum by controlling the vacuolar size and cell wall permeability is established during the study

    Effects of Exercise on Blood Glucose and Glycemic Variability in Type 2 Diabetic Patients with Dawn Phenomenon

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    Background. The dawn phenomenon (DP) is the primary cause of difficulty in blood glucose management in type 2 diabetic (T2D) patients, and the use of oral hypoglycemic agents has shown weak efficacy in controlling DP. Thus, this study is aimed at investigating the effect of moderate-intensity aerobic exercise before breakfast on the blood glucose level and glycemic variability in T2D patients with DP. Methods. A total of 20 T2D patients with DP confirmed via continuous glucose monitoring (CGM) participated in the current study. After collecting baseline measurements by CGM as a control, CGM was reinstalled and 30 minutes of moderate-intensity aerobic exercise was performed prior to breakfast. Dawn blood glucose increase, blood glucose levels, and glycemic variability were measured before and after exercise. Results. Dawn blood glucose increase (ΔGlu, 1.25±0.84vs.2.15±1.07, P=0.005), highest blood glucose value before breakfast (Gmax, 8.01±1.16vs. 8.78±1.09, P=0.005), and mean blood glucose (MBG, 7.80±0.97vs. 8.37±0.95, P=0.001) were all lower, and time in range (TIR, 90.75±12.27vs. 83.5±15.41, P=0.015) was higher after exercise than before exercise. Among the glycemic variability indicators, blood glucose standard deviation (SD, 1.1±0.5vs. 1.48±0.63, P=0.001), coefficient of variation (CV, 14.14±5.94vs.17.69±7.46, P=0.006), mean amplitude of glucose excursion (MAGE, 2.71±1.52vs.3.73±1.98, P=0.006), and largest amplitude of glucose excursion (LAGE, 4.97±2.07vs.6.41±2.36, P=0.002) were all decreased following exercise. Conclusions. Acute moderate-intensity aerobic exercise before breakfast reduced the morning rise of blood glucose in T2D patients, partially counteracting DP. Furthermore, exercise significantly reduced blood glucose fluctuations and improved blood glucose control throughout the day. We recommend that T2D patients with DP take moderate-intensity aerobic exercise before breakfast to improve DP and glycemic control

    An autocatalytic multicomponent DNAzyme nanomachine for tumor-specific photothermal therapy sensitization in pancreatic cancer

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    Abstract Multicomponent deoxyribozymes (MNAzymes) have great potential in gene therapy, but their ability to recognize disease tissue and further achieve synergistic gene regulation has rarely been studied. Herein, Arginylglycylaspartic acid (RGD)-modified Distearyl acylphosphatidyl ethanolamine (DSPE)-polyethylene glycol (PEG) (DSPE-PEG-RGD) micelle is prepared with a DSPE hydrophobic core to load the photothermal therapy (PTT) dye IR780 and the calcium efflux pump inhibitor curcumin. Then, the MNAzyme is distributed into the hydrophilic PEG layer and sealed with calcium phosphate through biomineralization. Moreover, RGD is attached to the outer tail of PEG for tumor targeting. The constructed nanomachine can release MNAzyme and the cofactor Ca2+ under acidic conditions and self-assemble into an active mode to cleave heat shock protein (HSP) mRNA by consuming the oncogene miRNA-21. Silencing miRNA-21 enhances the expression of the tumor suppressor gene PTEN, leading to PTT sensitization. Meanwhile, curcumin maintains high intracellular Ca2+ to further suppress HSP-chaperone ATP by disrupting mitochondrial Ca2+ homeostasis. Therefore, pancreatic cancer is triple-sensitized to IR780-mediated PTT. The in vitro and in vivo results show that the MNAzyme-based nanomachine can strongly regulate HSP and PTEN expression and lead to significant pancreatic tumor inhibition under laser irradiation
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