Zearalenone (ZEA) is a mycotoxin produced by
fungi that is commonly found in cereal crops. ZEA has an estrogen-like effect which affects the reproductive function of animals. It also damages the ...liver and kidneys and reduces immune function which leads to cytotoxicity and immunotoxicity. At present, the detoxification of mycotoxins is mainly accomplished using biological methods. Microbial-based methods involve zearalenone conversion or adsorption, but not all transformation products are nontoxic. In this paper, the non-pathogenic microorganisms which have been found to detoxify ZEA in recent years are summarized. Then, two mechanisms by which ZEA can be detoxified (adsorption and biotransformation) are discussed in more detail. The compounds produced by the subsequent degradation of ZEA and the heterogeneous expression of ZEA-degrading enzymes are also analyzed. The development trends in the use of probiotics as a ZEA detoxification strategy are also evaluated. The overall purpose of this paper is to provide a reliable reference strategy for the biological detoxification of ZEA.
The biosynthesis of C27–29 sterols from their C30 precursor squalene involves C24-alkylation and the removal of three methyl groups, including two at the C4 position. The two C4 demethylation ...reactions require a bifunctional enzyme known as 3β-hydroxysteroid dehydrogenase/C4-decarboxylase (3βHSD/D), which removes an oxidized methyl (carboxylic) group at C4 while simultaneously catalyzing the 3β-hydroxyl→3-keto oxidation. Its loss-of-function mutations cause ergosterol-dependent growth in yeast and congenital hemidysplasia with ichthyosiform erythroderma and limb defect (CHILD) syndrome in humans. Although plant 3βHSD/D enzymes were well studied enzymatically, their developmental functions remain unknown. Here we employed a CRISPR/Cas9-based genome-editing approach to generate knockout mutants for two Arabidopsis 3βHSD/D genes, HSD1 and HSD2, and discovered the male gametophytic lethality for the hsd1 hsd2 double mutation. Pollen-specific expression of HSD2 in the heterozygous hsd1 hsd2/+ mutant not only rescued the pollen lethality but also revealed the critical roles of the two HSD genes in embryogenesis. Our study thus demonstrated the essential functions of the two Arabidopsis 3βHSD/D genes in male gametogenesis and embryogenesis.
The study of patterns of crowd flows represents an emerging and expanding research field. The most straightforward and efficient approach to investigate the patterns of crowd flows is to concentrate ...on traffic flow. However, assessments of simple point-to-point movement frequently lack universal validity, and little research has been conducted on the regularity of nighttime movement. Due to the suspension of public transportation at night, taxi orders are critical in capturing the features of nighttime crowd flows in a tourism city. Using Haikou as an example, this paper proposes a mixed Geogrid Spatio-temporal model (MG-STM) for the tourism city in order to address the challenges. Firstly, by collecting the pick-up/drop-off/in-out flow of crowds, this research uses DCNMF dimensionality reduction to extract semi-supervised spatio-temporal variation features and the K-Means clustering method to determine the cluster types of nighttime crowd flows’ changes in each geogrid. Secondly, by constructing a mixed-evaluation model based on LJ1-01 nighttime light data, crowd flows’ clusters, and land use data in geogrid-based regions, the pattern of nighttime crowd flows in urban land use areas is successfully determined. The results suggest that MG-STM can estimate changes in the number of collective flows in various regions of Haikou effectively and appropriately. Moreover, population density of land use areas shows a high positive correlation with the lag of crowd flows. Each 5% increase in population density results in a 30-min delay in the peak of crowd flows. The MG-STM will be extremely beneficial in developing and implementing systems for criminal tracking and pandemic prevention.
Background and Objective
Cementum is a part of the periodontium and anchors periodontal ligaments to the alveolar bone. Cementoblasts are responsible for the cementum formation via matrix deposition ...and subsequently mineralization. Thus, exploring novel mechanisms underlying the function of cementoblast contributes to the treatment of cementum damage. Recently, circRNA Lrp6 (circLRP6) has been of interest due to its active role in cell differentiation, but its potential role in cementoblast differentiation remains unclear. Herein, we attempted to elucidate the role of circLRP6 in cementoblast differentiation and clarify any associated mechanisms.
Material and Methods
The mRNA expressions of circLRP6, miR‐145a‐5p, zinc finger E‐box binding homeobox 2 (Zeb2), runt‐related transcription factor 2 (Runx2), osteopontin (Opn), and bone sialoprotein (Bsp) were evaluated by qRT‐PCR. The protein levels of Zeb2 were measured by Western blot. Bioinformatic analysis and dual‐luciferase reporter assays were used to test the potential binding targets of miR‐145a‐5p. The differentiation potentials of the cementoblasts were assessed by Alkaline phosphatase (ALP) staining, ALP activity assay, Alizarin red S (ARS) staining, and quantification.
Results
In this study, circLRP6 was significantly upregulated in cementoblast differentiation. Furthermore, circLRP6 knockdown inhibited ALP levels, reduced calcium nodule formation and the expression of Runx2, Opn, and Bsp. Mechanically, bioinformatic analysis and dual‐luciferase reporter assays confirmed miR‐145a‐5p was a potential binding target of circLRP6. miR‐145a‐5p can negatively regulate cementoblast differentiation. Subsequently, bioinformatic analysis and dual‐luciferase reporter assays confirmed Zeb2 was a potential miR‐145a‐5p target. miR‐145a‐5p overexpression resulted in a downregulation of Zeb2. Furthermore, Zeb2 inhibition partially reversed the effect of circLRP6 during cementoblast differentiation.
Conclusion
Taken together, circLRP6 appears to modulate cementoblast differentiation by antagonizing the function of miR‐145a‐5p, thereby increasing Zeb2. This study serves as a stepping stone for the potential development of an approach to promote cementum formation.
This study evaluated the protective effect of proanthocyanidins (PCs) on reducing apoptosis in the mouse intestinal epithelial cell model MODE-K exposed to zearalenone (ZEA) through inhibition of the ...endoplasmic reticulum stress (ERS)-induced apoptosis pathway. Our results showed that PCs could reduce the rate of apoptosis in MODE-K cells exposed to ZEA (
< 0.01). PCs significantly increased the ZEA-induced antioxidant protective effects on the enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and on the content of GSH. PCs also significantly decreased the ZEA-induced increase in the content of malondialdehyde (MDA). The analysis indicated that ZEA increased both mRNA and protein expression levels of C/EBP homologous protein (CHOP), GRP78, c-Jun N-terminal kinase (JNK), and cysteinyl aspartate specific proteinase 12 (caspase-12) (
< 0.05), which are related to the ERS-induced apoptosis pathway. ZEA decreased levels of the pro-apoptotic related protein Bcl-2 (
< 0.05) and increased the anti-apoptotic related protein Bax (
< 0.05). Co-treatment with PCs was also shown to significantly reverse the expression levels of these proteins in MODE-K cells. The results demonstrated that PCs could protect MODE-K cells from oxidative stress and apoptosis induced by ZEA. The underlying mechanism may be that PCs can alleviate apoptosis in mouse intestinal epithelial cells by inhibition of the ERS-induced apoptosis pathway.
Hydrogen energy, the cleanest fuel, presents extensive applications in renewable energy technologies such as fuel cells. However, the transition process from carbon-based (fossil fuel) energy to ...desired hydrogen energy is usually hindered by inevitable scientific, technological, and economic obstacles, which mainly involves complex hydrocarbon reforming reactions. Hence, this paper provides a systematic and comprehensive analysis focusing on the hydrocarbon reforming mechanism. Accordingly, recent related studies are summarized to clarify the intrinsic difference among the reforming mechanism. Aiming to objectively assess the activated catalyst and deactivation mechanism, the rate-determining steps of reforming process have been emphasized, summarized, and analyzed. Specifically, the effect of metals and supports on individual reaction processes is discussed followed by the metal-support interaction. Current tendency and research map could be established to promote the technology development and expansion of hydrocarbon reforming field. This review could be considered as the guideline for academics and industry designing appropriate catalysts.
The study was conducted to investigate whether combined use of
Sx-01 and
C-1-3 could improve the intestinal health and reduce the lipid levels in sera of mice and whether these benefits were related ...to regulating the intestinal microflora. Eighty Kunming male mice were divided into four groups with five replicates per group and four mice per replicate. Mice in the control group were administrated with 0.2 mL normal saline; mice in three experimental groups were daily orally administrated with 4 × 10⁸ cfu of
, 4 × 10⁸ cfu of
, and a combination thereof (2 × 10⁸ cfu of
, and 2 × 10⁸ cfu of
), respectively. The experiment lasted for 14 days. The results showed that the average daily feed intake (ADFI) and feed/gain (F/G) ratio of growing mice underwent no significant changes (
> 0.05); however, the average daily gain (ADG) tended to increase over short periods of time. The activities of SOD and GSH-Px in serum in the combination group were significantly increased (
< 0.05); The triglyceride, and total cholesterol, contents in serum in the combined treatment group were significantly decreased (
< 0.05); The total volatile fatty acids and butyric acid in faecal matter of mice in the experimental groups were all significantly increased at 14 days (
< 0.05); The length of villi, and the mucosal thickness of colon and caecum (
< 0.05) were significantly improved; The relative abundance of some bacteria with antioxidant capacity or decomposing cholesterol capacity or butyrate producing capacity was increased, while the relative abundance of some pathogenic bacteria was decreased in the colon. Furthermore, our results showed that the beneficial effects of the combined use of the two strains was higher than that of single use. Overall, the results demonstrated that the combined use of
Sx-01 and
C-1-3 can significantly improve intestinal health and reduce the amount of lipids in sera of mice. The reason for these effects might be that besides their own probiotic effects, combined use of the two strains could regulate the intestinal microflora.
Robot-assisted retinal cannulation is an eye surgical procedure which can dissolve the obstruction by using robot to inject anticoagulant into occluded vessel. The current research on the critical ...parameters of cannulation for human is scarce because of the immature technology. Considering the influence of microneedle, this work investigated the effects of drug concentration, injection velocity, injection position, and size of clot on cannulation by theoretical analysis and finite element analysis. For finite element analysis, the multiphysics continuum model was established to demonstrate species transport and reaction which simulates the entire lytic process of the occlusive clot, and four cell zones were established to describe the generation of plasmin (PLS) with the addition of tissue-type plasminogen activator (tPA) and fibrinolysis of clot by importing subroutines into each cell zone under the conditions of constant clot size and variable size, respectively. The results imply that the most efficient value of tPA concentration is 50 nM, injection velocity is 60 mm/s for clot length of 0.1 mm, and the best position to insert the cannula is 0.5 mm in front of the thrombus. For different clot lengths of 0.1 mm to 0.6 mm, the optimal range of tPA concentration and injection velocity is from 20 nM to 70 nM and from 40 mm/s to 60 mm/s, respectively, and explores the reasonable injection position of 0.3 mm to 0.5 mm in front of clot in a vein of 100 μm. This conclusion can be used to perform robot-assisted cannulation surgery to improve fibrinolytic efficiency.
Genetic algorithm (GA) has strong global search ability and is easy to operate, but it has some disadvantages, such as slow convergence speed, and easy to fall into local extreme. In order to ...overcome these disadvantages, an improved genetic algorithm is proposed in this paper. Firstly, instead of the random initialization method, a uniform partition multi-population initialization method is used to generate the initial populations. This method calculates clustering centers by the criterion of Hamming distance, so as to generate different populations. The algorithm can make the initial solutions disperse in the solution space as much as possible, thus avoiding the problem of local extremes. Secondly, the ideas of multi-population parallel mechanism and learning mechanism are introduced to further improve the performance of algorithm. Based on the analysis of advantages and disadvantages of the two mechanisms, new improvements are made to these two mechanisms. Modified multi-population parallel mechanism and o
To solve the shortcomings of sparrow search algorithm (SSA), such as falling into local extremum easily influenced by initial solution and slow convergence in late iteration, a multi-chaotic sparrow ...search algorithm based on learning mechanism (MMCSSA) is proposed. Firstly, the centroid opposition-based learning strategy (COBL) is introduced to generate elite population to enhance the exploration of multi-source high-quality search areas, and then the local extreme escape ability and convergence performance of the algorithm are improved. Secondly, a scaled golden sine algorithm is proposed and embedded in SSA to improve the guidance search mode and enhance the global search ability of the algorithm. Thirdly, a multi-chaos mapping strategy based on learning mechanism is proposed, which utilizes the characteristics of multi-chaos and multi-disturbance, and enforces different disturb-ance features on the algorithm by dynamically calling different chaotic maps. When chaotic perturbation fails, Gaussian mutation s
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