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In this study, the structure-activity relationship of finger citron polysaccharides (FCPs) and their phosphorylated derivatives (P-FCPs) was investigated. Three FCPs (FCP20, FCP40 and FCP60) were successively fractionated by ethanol, and were phosphorylated modification to obtain P-FCPs (P-FCP20, P-FCP40 and P-FCP60). FCPs and P-FCPs are acidic heteropolysaccharides composed of mannose, rhamnose, glucose, galactose, arabinose and galacturonic acid, and exhibited different content of neutral sugar, uronic acid, proteins, polyphenols and sulfates. FTIR and NMR analyses determined the structures of FCPs and P-FCPs, indicating that the phosphorylation modification was successful. P-FCPs possessed the smaller molecular weight distribution and particle size, with significant changes in microstructure than FCPs. Additionally, P-FCPs showed significantly increased antioxidant and α-amylase inhibitory activities compared to FCPs. The inhibitory mechanisms of FCP40 and P-FCP40 on α-amylase was a mixed-type manner and dynamic fluorescence quenching. The results demonstrate that phosphorylation modification can alter the structural features and bioactivities of FCPs, providing an approach for the further development of finger citron in the field of medicinal and functional foods. • Three polysaccharides from finger citron (FCPs) were obtained by gradient ethanol precipitation. • Three phosphorylated derivatives of finger citron polysaccharides (P-FCPs) were prepared by the phosphate method. • The structural characteristics and physicochemical properties of FCPs and P-FCPs were analyzed. • P-FCPs showed better antioxidant and α-amylase inhibitory activity than FCPs. • FCP40 and P-FCP40 interact with α-amylase through mixed-type inhibition and dynamic fluorescence quenching. [ABSTRACT FROM AUTHOR]

Acidic sugarcane leaf polysaccharide (ASLP) has a variety of biological activities, but its macromolecular properties make it difficult for the human body to completely absorb or metabolize quickly in the body, and the action time is short. To solve this problem, acidic sugarcane leaf polysaccharide liposomes (ASLPL) were prepared by reverse evaporation method and characterized for encapsulation efficiency, particle size, potential, morphology, rheology and stability. In vitro release and digestion tests were used to verify the sustained release effect and stability of ASLPL. The results showed that ASLPL was spherical, with an encapsulation rate of 86.19% ± 0.976%, a particle size of 134.57 ± 2.501 nm, and a zeta potential of −24.49 ± 1.002 mV, which was a pseudoplastic fluid that was more stable to be stored in a neutral environment at 4 °C. The antioxidant, hypolipidemic and antibacterial activities of ASLPL were significantly increased compared with those of ASLP. The in vitro release and digestion results showed that ASLPL had obvious sustained release effect and could slow down the digestion of ASLP in vivo and prolong the duration of action. Therefore, the development and utilization of ASLPL can provide a greater development potential for the further application of ASLP in the food and pharmaceutical fields. [Display omitted] • ASLPL is a typical pseudoplastic fluid with good stability. • The biological activity of ASLPL was significantly higher than that of ASLP. • ASLPL has obvious sustained release effect and improves the digestive stability of ASLP. • ASLPL is expected to develop into a new type of biological agent. [ABSTRACT FROM AUTHOR]

As a waste of sugarcane, the added value of sugarcane leaves has not been fully utilized, and sugarcane leaf polysaccharide is an important active component of sugarcane leaves. Using new extraction methods to study the structure and biological activity of polysaccharides from sugarcane leaves is of great significance for the development and application of sugarcane leaves. To determine the structural characteristics and biological activities of different acidic sugarcane leaf polysaccharides (ASLPs) extracted by microwave-assisted hot alkali extraction (MALE), three new acidic sugarcane leaf polysaccharides (ASLP-50, ASLP-70 and ASLP-90) were precipitated by ethanol. The structure of ASLPs extracted by MALE contains protein, sulfate and uronic acid. ASLP-50 (195.88 kDa), ASLP-70 (94.62 kDa) and ASLP-90 (16.37 kDa) were acidic polysaccharides composed of mannose, galacturonic acid, glucose, arabinose and fucose. The results of XRD and NMR showed that ASLPs were amorphous polysaccharides composed of α-L-Araf-(1→ main chain, and its branching points were composed of Arap and GalpA residues. In addition, ASLPs showed significant antioxidant, hypoglycemic, hypolipidemic and antibacterial activities in vitro. The research and application of ASLPs provide a reference for the recycling of sugarcane leaves, which is conducive to the development of food, agriculture and pharmaceutical industries. [Display omitted] • Three acidic polysaccharides were obtained from sugarcane leaves by MALE. • ASLPs showed strong antioxidant, hypoglycemic and hypolipidemic potential in vitro. • ASLPs have certain antibacterial activity. • ASLPs have great potential for development and application in many fields. [ABSTRACT FROM AUTHOR]

• A label-free sensor based on Au NRs was proposed for ultra-sensitive detection of thiabendazole. • SERS spectra were subtracted baseline shift by Adaptive Iterative Re-weighted Penalized Least Squares. • Chemometric models were used for spectral mining and predictive modeling. • The limit of detection achieved was lower than the Ministry of Agriculture of China set standard of thiabendazole in citrus. Citrus is a highly consumed fruit worldwide. However, the excessive use of thiabendazole (TBZ) pesticides during citrus cultivation poses a health risk to people. Hence, a rapid and quantitative method has been established for TBZ determination in citrus by coupling gold nanorods (Au NRs) based surface enhanced Raman scattering (SERS) coupling chemometrics. The results show that support vector machine (SVM) can distinguish TBZ residues of different orders of magnitude with 99.1667% accuracy and that genetic algorithm-partial least squares (GA-PLS) had the best performance in the quantitative prediction of TBZ residues (Rp2 = 0.9737, RMSEP = 0.1179 and RPD = 5.85) in citrus. The limit of detection (LOD) was 0.33 μg mL−1. Furthermore, the proposed method was validated by a standard HPLC method using t -test with no significant difference. Therefore, the proposed Au NRs-based SERS technique can be used for the rapid quantitative analysis of TBZ residues in citrus. [ABSTRACT FROM AUTHOR]

Summary: Negative elongation factor (NELF) is known to enforce promoter-proximal pausing of RNA polymerase II (Pol II), a pervasive phenomenon observed across multicellular genomes. However, the physiological impact of NELF on tissue homeostasis remains unclear. Here, we show that whole-body conditional deletion of the B subunit of NELF (NELF-B) in adult mice results in cardiomyopathy and impaired response to cardiac stress. Tissue-specific knockout of NELF-B confirms its cell-autonomous function in cardiomyocytes. NELF directly supports transcription of those genes encoding rate-limiting enzymes in fatty acid oxidation (FAO) and the tricarboxylic acid (TCA) cycle. NELF also shares extensively transcriptional target genes with peroxisome proliferator-activated receptor α (PPARα), a master regulator of energy metabolism in the myocardium. Mechanistically, NELF helps stabilize the transcription initiation complex at the metabolism-related genes. Our findings strongly indicate that NELF is part of the PPARα-mediated transcription regulatory network that maintains metabolic homeostasis in cardiomyocytes. [Copyright &y& Elsevier]

Many mammalian genes are occupied by paused RNA polymerase II (pol II) in the promoter-proximal region on both sides of the transcription start site. However, the impact of pol II pausing on gene expression and cell biology is not fully understood. In this study, we used a Cre-Lox system to conditionally knock out the b subunit of mouse negative elongation factor (Nelf-b), a key pol II-pausing factor, in mouse embryonic fibroblasts. We found that Nelf-b was associated with the promoter-proximal region of the majority of expressed genes, yet genetic ablation of Nelf-b only affected the steady-state mRNA levels of a small percentage of the Nelf-b-associated genes. Interestingly, Nelf-b deletion also increased levels of transcription start site upstream transcripts at multiple negative elongation factor-associated genes. The direct target genes of Nelf-b were highly enriched with those involved in the control of cell growth and cell death. Correspondingly, Nelf-b knock-out mouse embryonic fibroblasts exhibited slower progression from quiescence to proliferation, as well as in a cycling cell population. Furthermore, Nelf-b deletion also resulted in increased apoptosis. Thus, the genetic and genomic studies provide new physiological and molecular insight into Nelf-mediated pol II pausing. [ABSTRACT FROM AUTHOR]

As an important part of the power system, power load forecasting directly affects the national economy. Small improvements in power load forecasts can save millions of dollars for the power industry. Therefore, improving the accuracy of power load forecasting has always been the pursuing goal for a power system. Based on this goal, this paper proposes a novel connection, the dense average connection, in which the outputs of all preceding layers are averaged as the input of the next layer in a feed-forward fashion. Dense average connection can alleviate the problem of gradient explosion without introducing new parameters. Based on dense average connection, we construct the dense average network (DaNet) for power load forecasting. On two public datasets (ISO-NE dataset and NAU dataset), we use MAPE, MAE and RMSE to evaluate the performance of DaNet. The predictions of DaNet are better than those of existing benchmarks. On this basis, this paper uses the ensemble method to reduce the peak value of prediction bias, which helps to alleviate the dispatching problem caused by unexpected loads. To verify the reliability of the model predictions, the robustness is analyzed and verified by adding input disturbances. The experimental results show that the proposed model is effective and robust for power load forecasting. [ABSTRACT FROM AUTHOR]