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1.
Food Chem ; 339: 127813, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916401

RESUMO

Bisphenol S (BPS), a structural analog of Bisphenol A (BPA), has been widely used as a substitute for epoxy resin, food packaging materials, and other products due to the limited application of BPA. Studies in vivo and in vitro have indicated that BPA could induce fat accumulation like an obesogen. The main goal of this study was to investigate the role and mechanism of BPS in lipid metabolism using Caenorhabditis elegans (C. elegans) as a model. Results showed that both the overall fat deposition and the triglyceride level were significantly increased in a non-monotonically increasing trend, and the low dose of BPS (0.01 µM) exhibited a stronger influence. Additionally, BPS enhanced fat synthesis depending on daf-16, fat-5, fat-6 and fat-7, and inhibited fatty acid oxidation via nhr-49 and acs-2. This study further indicate that fat accumulation induced by BPS requires nhr-49, which also mediated the nuclear hormone signaling pathway.

2.
Cell Death Differ ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188281

RESUMO

Metastatic melanoma remains a challenging disease. Understanding the molecular mechanisms how melanoma becomes metastatic is therefore of interest. Herein we show that downregulation of the AP-1 transcription factor member Fra-2 in melanoma cells is associated with an aggressive melanoma phenotype in vitro and in vivo. In vitro, Fra-2 knockdown in melanoma cells promoted cell migration and invasion associated with increased Snail-1, Twist-1/2, and matrix metalloproteinase-2 (MMP-2) expression. In vivo, Fra-2 knockdown in a melanoma cell line led to increased metastasis into the lungs and liver. The increased metastatic potential of Fra-2 knockdown melanoma cells was likely due to an accelerated cell cycle transition and increased tissue angiogenesis. Using Fra-2 knockdown cell lines microarray analysis, we identified the protein Fam212b (family with sequence similarity 212 member B) as a downstream target of Fra-2. By additional knockdown of Fam212b in Fra-2 mutant cells, we mitigated the cell migration, invasion, and cell cycle transition phenotype induced by Fra-2 knockdown. Furthermore, Fam212b overexpression enhanced ß-catenin pathway. Finally, Fam212b expression is correlated with increased melanoma metastasis and poor clinical outcomes in human patients. In summary, these findings reveal the Fra-2-Fam212b axis as a new pathway of melanoma metastasis, which can be in the future used as potential marker of the metastatic properties of melanoma.

3.
Bioresour Technol ; 320(Pt A): 124314, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33147527

RESUMO

Hydrogen production from renewable resources via microbial electrolysis cells (MECs) is a promising approach for sustainable energy production. Yet high hydrogen yield from real feedstocks has not been demonstrated in up-scaled MECs. In this study, a 10-L single chamber MEC with a high electrode surface area to volume ratio (66 m2/m3) was constructed and electroactive cathodic biofilms were enriched for hydrogen evolution reaction. A high hydrogen yield of 91% was achieved using lignocellulosic hydrolysate with a hydrogen production rate of 0.71 L/L/D at an organic loading rate of 0.4 g/D. The anodic and cathodic microbial communities, with Enterococcus spp. as the known electroactive bacteria, were capable of achieving current densities of 13.7 A/m2 and 16.5 A/m2, respectively. A machine learning algorithm was used to investigate the correlation between community data and electrochemical performance, and the critical genera on determining current density were identified.

4.
Neuroreport ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33196547

RESUMO

Identifying outcome predictors for ischemic stroke is beneficial for choosing correct intervention protocols. Thus, it is necessary to systemically evaluate histological outcome-associated changes such as hemodynamics, behavior, and body weight during the early phase of ischemia. Here, 50 mice were subjected to 45-min middle cerebral artery occlusion (MCAO) using Longa's method. Hemodynamic changes were monitored by Doppler laser probe, and behaviors were evaluated by scales while the tissues were visualized by staining. The results by correlation analysis demonstrated that with a probe located near the posterior boundary zone of MCA territory, the latency of anoxic depolarization, as well as the cerebral blood flow reduction during MCAO were confirmed to be predictors for the infarct volume on day 3 post-ischemia; histology showed that the risk of a space-occupying secondary hemorrhage was significantly correlated with the increase of infarct volume versus the traditional Bederson's neurological deficit scale, a renewed combined behavioral scoring method performed nicely to reflect the severity of tissue lesions. Weight loss was a valuable metric for the enlargement of both infarct volume and secondary hemorrhage. Monitoring changes during early-phase ischemia may benefit the optimization of ischemia models and the discovery of potential intervention targets.See Video Abstract, http:/links.lww.com/WNR/A601).

5.
Biomed Res Int ; 2020: 8790531, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33150183

RESUMO

Background: Cleft lip with or without cleft palate (CL/P) is the most common facial birth defect, with a worldwide incidence of 1 in 700-1000 live births. CL/P can be divided into syndromic CL/P (SCL/P) and nonsyndromic CL/P (NSCL/P). Genetic factors are an important component to the etiology of NSCL/P. ARHGAP29, one of the NSCL/P disease-causing genes, mediates the cyclical regulation of small GTP binding proteins such as RhoA and plays an essential role in cellular shape, proliferation, and craniofacial development. Methods: The present study investigated a Chinese family with NSCL/P and explored potential pathogenic variants using whole-exome sequencing (WES). Variants were screened and filtered through bioinformatic analysis and prediction of variant pathogenicity. Cosegregation was subsequently conducted. Results: We identified a novel heterozygous missense variant of ARHGAP29 (c.2615C > T, p.A872V) in a Chinese pedigree with NSCL/P. Conclusion: We detected the disease-causing variant in this NSCL/P family. Our identification expands the genetic spectrum of ARHGAP29 and contributes to novel approaches to the genetic diagnosis and counseling of CL/P families.

6.
Environ Pollut ; : 115943, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33158624

RESUMO

Electrochemically active bacteria (EAB) are effective for the bioreduction of nitroaromatic compounds (NACs), but the exact reduction mechanisms are unclear yet. Therefore, 3-nitrobenzenesulfonate (NBS) was used to explore the biodegradation mechanism of NACs by EAB. Results show that NBS could be anaerobically degraded by Shewanella oneidensis MR-1. The generation of aminoaromatic compounds was accompanied with the NBS reduction, indicating that NBS was biodegraded via reductive approach by S. oneidensis MR-1. The impacts of NBS concentration and cell density on the NBS reduction were evaluated. The removal of NBS depends mainly on the transmembrane electron transfer of S. oneidensis MR-1. Impairment of Mtr respiratory pathway was found to mitigate the reduction of NBS, suggesting that the anaerobic biodegradation of NBS occurred extracellularly. Knocking out cymA severely impaired the extracellular reduction ability of S. oneidensis MR-1. However, the phenotype of ΔcymA mutant could be compensated by the exogenous electron mediators, implying the trans-outer membrane diffusion of mediators into the periplasmic space. This work provides a new insight into the anaerobic reduction of aromatic contaminants by EAB.

7.
Anal Chem ; 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33166462

RESUMO

Modulating the active sites of oxygen vacancies (OVs) to enhance the catalytic properties of nanomaterials has attracted much research interest in various fields, but its intrinsic catalytic mechanism is always neglected. Herein, we establish an efficient strategy to promote the electrochemical detection of Pb(II) by regulating the concentration of OVs in α-MoO3 nanorods via doping Ce3+/Ce4+ ions. α-MoO3 with the Ce-doped content of 9% (C9M) exhibited the highest detection sensitivity of 106.64 µM µA-1 for Pb(II), which is higher than that achieved by other metal oxides and most precious metal nanomaterials. It is found that C9M possessed the highest concentration of OVs, which trapped some electrons for strong affinity interaction with Pb(II) and provided numerous atomic level interfaces of high surface free energy for catalysis reactions. X-ray absorption fine structure spectra and density functional theory calculation indicate that Pb(II) was bonded with the surface-activated oxygen atoms (Os) around Ce ions and obtained some electrons from Os. Besides, the longer Pb-O bonds on C9M were easier to break, causing a low desorption energy barrier to effectively accelerate Pb(II) desorbing to the electrode surface. This study helps to understand the changes in electronic structure and catalytic performance with heteroatom doping and OVs in chemically inert oxides and provide a reference for designing high-active electrocatalytic interfaces to realize ultrasensitive analysis of environmental contaminants.

8.
Int J Biol Macromol ; 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33172614

RESUMO

Bitter melon polysaccharides (BPS) have been reported to have hypolipidemic effects. However, the precise mechanism of BPS regulating lipid metabolism remains elusive. Water-soluble (WBPS) and alkali-soluble bitter melon polysaccharides (ABPS) were extracted to evaluate the fat-lowering bioactivities in HepG2 cells and Caenorhabditis elegans. WBPS and ABPS were slightly different in the uronic acid contents (22.23% and 5.69%), monosaccharide composition, molecular weight (Mw: 332 kDa and 1552 kDa, respectively) and IR spectra. In palmitic acid-treated HepG2 cell, the ABPS exhibited better effects on accelerating glucose consumption and decreasing the triglyceride content than WBPS via stimulating glucose consumption (GLUT4) and gluconeogenesis (PEPCK). In the model of glucose-treated C. elegans, we observed that both WBPS and ABPS obviously suppressed the fat accumulation, more significantly by ABPS, along with no toxicity towards some physical activities. Fat-5, fat-6 and fat-7 mediated fatty acid desaturases pathways were further confirmed to be involved in the lipid-lowering effects of BPSs. Our studies demonstrated that both WBPS and ABPS can exhibit effects on fat- lowering in HepG2 cells and C. elegans.

9.
Chemosphere ; : 128715, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33160651

RESUMO

PM2.5-attributable deaths and years of life lost (YLL) due to specific causes during 1998-2015 in India were estimated using the integrated exposure-response (IER) model. The estimated PM2.5-mortality in India revealed an annual increasing rate of 2.7% during the study period. Spatially, deaths due to the exposure to ambient PM2.5 concentrated mostly in populated North India, and four northern states contributed 43% to the national PM2.5-attributable deaths in 2015. PM2.5-attributable deaths in India increased by 21% during 1998-2015 due to the changes of PM2.5 only, and deaths due to lung cancer (LC) revealed the largest sensitivity to increasing ambient PM2.5. The findings of this study suggest that aggressive air pollution control strategies should be implemented in North India due to their dominant contributions to the current health risks. Moreover, the rapid growth of LC related deaths with increasing ambient PM2.5 should not be neglected.

10.
IEEE Trans Cybern ; PP2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175688

RESUMO

Conventional nonlinear subspace learning techniques (e.g., manifold learning) usually introduce some drawbacks in explainability (explicit mapping) and cost effectiveness (linearization), generalization capability (out-of-sample), and representability (spatial-spectral discrimination). To overcome these shortcomings, a novel linearized subspace analysis technique with spatial-spectral manifold alignment is developed for a semisupervised hyperspectral dimensionality reduction (HDR), called joint and progressive subspace analysis (JPSA). The JPSA learns a high-level, semantically meaningful, joint spatial-spectral feature representation from hyperspectral (HS) data by: 1) jointly learning latent subspaces and a linear classifier to find an effective projection direction favorable for classification; 2) progressively searching several intermediate states of subspaces to approach an optimal mapping from the original space to a potential more discriminative subspace; and 3) spatially and spectrally aligning a manifold structure in each learned latent subspace in order to preserve the same or similar topological property between the compressed data and the original data. A simple but effective classifier, that is, nearest neighbor (NN), is explored as a potential application for validating the algorithm performance of different HDR approaches. Extensive experiments are conducted to demonstrate the superiority and effectiveness of the proposed JPSA on two widely used HS datasets: 1) Indian Pines (92.98%) and 2) the University of Houston (86.09%) in comparison with previous state-of-the-art HDR methods. The demo of this basic work (i.e., ECCV2018) is openly available at https://github.com/danfenghong/ECCV2018_J-Play.

11.
Int J Biol Macromol ; 165(Pt B): 1664-1674, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33038396

RESUMO

Liriomyza spp. (Diptera: Agromyzidae) represent a group of economically-significant highly polyphagous pests of plants grown in field and greenhouse conditions. Liriomyza spp. share similar biological and morphological characteristics, and complex interspecific interactions have been documented among these species in various geographical regions. Where the displacement of one of these species by the other has been studied, no unique mechanisms have been identified as causing it. The impact of competitive factors (such as, insecticide tolerance, thermotolerance, and adaptability to cropping systems) may be unique to specific geographic regions of Liriomyza spp., but more research is needed to confirm these hypotheses. In this study, RNA-seq was used to determine the transcriptomes of three closely-related leafminers, e.g. L. sativae, L. trifolii, and L. huidobrensis. Over 20 Gb of clean reads were generated and assembled into unique transcriptomes, and 38,747 unigenes were annotated in different databases. In pairwise comparisons, L. trifolii and L. sativae had more up-regulated genes than L. huidobrensis. With respect to common differentially-expressed genes (Co-DEGs), the three leafminers exhibited distinct groups of highly-expressed gene clusters. When genes related to competitive factors were compared, expression patterns in L. trifolii and L. sativae were more closely related to each other than to L. huidobrensis. The data suggest that DEGs involved in competitive factors may play a key role in competition and displacement of leafminers. The divergent genes identified in this study will be valuable in revealing possible mechanisms of invasion, displacement and interspecific competition in Liriomyza spp.

12.
Food Funct ; 11(10): 9157-9167, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33026384

RESUMO

Oenothein B (OEB) has various biological functions, although few studies have focused on its effect on in vivo metabolic phenotypes. In the present study, the systematic antioxidant activity of OEB was evaluated both in vitro and in vivo, and the effect of OEB on metabolic pathways related to antioxidant capacity of Caenorhabditis elegans (C. elegans) was explored. Our findings indicate that OEB exhibits great antioxidant capacity and ability to scavenge free radicals and that OEB treatment can protect RAW 264.7 macrophages from oxidative damage by increasing superoxide dismutase (SOD) activity, catalase (CAT) activity and glutathione (GSH) content and the corresponding gene expression (sod2, cat, gpx1), while decreasing malonic dialdehyde (MDA) content. Moreover, OEB treatment significantly reduced ROS accumulation under oxidative stress conditions and increased glutathione peroxidase (GPx) activity and decreased MDA content in C. elegans. Metabolomics analysis revealed that sixteen out of forty-two significantly altered metabolites were selected as potential biomarkers related to alterations in the antioxidant status of worms, including metabolic pathways involved in amino acid metabolism, taurine and hypotaurine metabolism, lipid metabolism, and purine metabolism. Overall, our results provide new insights into the effects of OEB treatment on antioxidant capacity and metabolism that suggest that OEB could be a potentially good source of natural antioxidants.

15.
J Food Biochem ; 44(11): e13459, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32885854

RESUMO

Barley, a kind of cereal, is rich in polysaccharides, phenols, proteins, ß-glucan, etc. Our previous studies discovered that extracts from Lactobacillus plantarum dy-1-fermented barley (LFBE) held strong anti-obesity property in obese rats through inhibiting inflammation and suppressing the differentiation in 3T3-L1 preadipocytes; however, the precise mechanism of LFBE regulating lipid metabolism remains elusive. Results suggested LFBE and its main active components, especially the total phenols, exhibited fat-lowering effects in glucose treated Caenorhabditis elegans at a certain concentration. Additionally, LFBE and the main components changed related genes in the insulin signaling pathway, fatty acid oxidation, and synthesis. Following verification study using mutants confirmed that the daf-2 gene rather than the daf-16 gene was required in LFBE and main components regulating lipid metabolism, which also involved in the process of fatty acid ß-oxidation and unsaturated fatty acid synthesis. Results demonstrated that LFBE and its main bioactivate compounds inhibited fat accumulation partly in a daf-2-dependent mechanism. PRACTICAL APPLICATIONS: Our previous studies have reported that extracts of fermented barley exhibited anti-obesity activity. However, little is known about which functional factors play a leading role in decreasing fat deposition and its precise mechanism. Results indicated that daf-2 mediated signaling pathways involved in the fat-lowering effects of LFBE and its main components. Our findings are beneficial to understand the main nutritional ingredients in LFBE which are ideal and expected in functional foods for the obese.

16.
J Food Biochem ; 44(11): e13471, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32985001

RESUMO

Fermented barley (FB) flour by Lactobacillus plantarum is richer in dietary fiber, polyphenols, gamma-aminobutyric acid, and other biologically active ingredients. This study aimed to determine the impacts of fermented barley - wheat flour compound noodle (FBWN) on glucose and fat metabolism in subjects with metabolic syndrome. This was a single-blinded and parallel 10-week clinical trial study. Subjects were randomly assigned into the trial group (FBWN) and whole wheat noodles group (WWN), and were measured on the beginning of week 3 and the ending of week 10. The glucose level at 30 and 60 min was significantly decreased after FBWN intervention. Levels of fasting blood glucose, HbA1c, and TG were all declined after FBWN intervention compared to before in the trial group. Moreover, the fat mass, fat rate, and visceral fat were decreased by 6.48, 7.19, 6.3 kg after FBWN intervention, respectively, while muscle mass and basal metabolic rate rose 7.44 kg and 252.60 kcal. PRACTICAL APPLICATIONS: Many studies have illustrated that the extraction of fermented barley held the activities of anti-obesity, antitumor, and so on. Moreover, this present study evaluated the effects of fermented barley by Lactobacillus plantarum on patients with metabolic syndrome. Results indicated that FB benefits the subjects on improving plasma glycolipids and insulin sensitivity, decreasing visceral fat level, and increasing satiety. The findings showed that the products of FB may be beneficial to dietary manipulations, thus, reducing the burden of patients.

17.
Anal Methods ; 12(25): 3250-3259, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32930188

RESUMO

Lactic acid (LA) plays an important role in the tumor metabolism and malignant progression of various cancers. Herein, we have developed a one-step, wash-free microfluidic approach with droplet biosensors for the sensitive detection of LA secreted by a single tumor cell. Our assay integrates the enzyme-assisted chemical conversion of LA in small-volume (4.2 nL) droplets for fluorescence signal readout. The microdroplet assay achieved a limit of detection of 1.02 µM and was more sensitive than the commercial ELISA kit by nearly two orders of magnitude. A good specificity has been demonstrated for this assay by testing various ions and biomolecules from the culture medium. This droplet assay allows us to acquire the profiles of the lactic acid secretion of tumor cells under the influence of glycolytic inhibitors at the single-cell level. It offers a useful research tool to study the cell-to-cell differences of LA secretion and glycolytic inhibitor screening for cancer research.

18.
Microb Ecol ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32995929

RESUMO

Piezophiles, by the commonly accepted definition, grow faster under high hydrostatic pressure (HHP) than under ambient pressure and are believed to exist only in pressurized environments where life has adapted to HHP during evolution. However, recent findings suggest that piezophiles have developed a common adaptation strategy to cope with multiple types of stresses including HHP. These results raise a question on the ecological niches of piezophiles: are piezophiles restricted to habitats with HHP? In this study, we observed that the bacterial strains Sporosarcina psychrophila DSM 6497 and Lysinibacillus sphaericus LMG 22257, which were isolated from surface environments and then transferred under ambient pressure for half a century, possess moderately piezophilic characteristics with optimal growth pressures of 7 and 20 MPa, respectively. Their tolerance to HHP was further enhanced by MgCl2 supplementation under the highest tested pressure of 50 MPa. Transcriptomic analysis was performed to compare gene expression with and without MgCl2 supplementation under 50 MPa for S. psychrophila DSM 6497. Among 4390 genes or transcripts obtained, 915 differentially expressed genes (DEGs) were identified. These DEGs are primarily associated with the antioxidant defense system, intracellular compatible solute accumulation, and membrane lipid biosynthesis, which have been reported to be essential for cells to cope with HHP. These findings indicate no in situ pressure barrier for piezophile isolation, and cells may adopt a common adaptation strategy to cope with different stresses.

19.
BMC Genomics ; 21(1): 577, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32831009

RESUMO

BACKGROUND: Drought is one of the most adverse environmental factors limiting crop productions and it is important to identify key genetic determinants for food safety. Calcium-dependent protein kinases (CPKs) are known to be involved in plant growth, development, and environmental stresses. However, biological functions and regulatory mechanisms of many plant CPKs have not been explored. In our previous study, abundance of the wheat CPK34 (TaCPK34) protein was remarkably upregulated in wheat plants suffering from drought stress, inferring that it could be involved in this stress. Therefore, here we further detected its function and mechanism in response to drought stress. RESULTS: Transcripts of the TaCPK34 gene were significantly induced after PEG-stimulated water deficiency (20% PEG6000) or 100 µM abscisic acid (ABA) treatments. The TaCPK34 gene was transiently silenced in wheat genome by using barley stripe mosaic virus-induced silencing (BSMV-VIGS) method. After 14 days of drought stress, the transiently TaCPK34-silenced wheat seedlings showed more sensitivity compared with control, and the plant biomasses and relative water contents significantly decreased, whereas soluble sugar and MDA contents increased. The iTRAQ-based quantitative proteomics was employed to measure the protein expression profiles in leaves of the transiently TaCPK34-silenced wheat plants after drought stress. There were 6103 proteins identified, of these, 51 proteins exhibited significantly altered abundance, they were involved in diverse function. And sequence analysis on the promoters of genes, which encoded the above identified proteins, indicated that some promoters harbored some ABA-responsive elements. We determined the interactions between TaCPK34 and three identified proteins by using bimolecular fluorescent complementation (BiFC) method and our data indicated that TaCPK34directly interacted with the glutathione S-transferase 1 and prx113, respectively. CONCLUSIONS: Our study suggested that the TaCPK34 gene played positive roles in wheat response to drought stress through directly or indirectly regulating the expression of ABA-dependent manner genes, which were encoding identified proteins from iTRAQ-based quantitative proteomics. And it could be used as one potential gene to develop crop cultivars with improved drought tolerance.

20.
Comput Med Imaging Graph ; 84: 101765, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32810817

RESUMO

Dermoscopic images are widely used for melanoma detection. Many existing works based on traditional classification methods and deep learning models have been proposed for automatic skin lesion analysis. The traditional classification methods use hand-crafted features as input. However, due to the strong visual similarity between different classes of skin lesions and complex skin conditions, the hand-crafted features are not discriminative enough and fail in many cases. Recently, deep convolutional neural networks (CNN) have gained popularity since they can automatically learn optimal features during the training phase. Different from existing works, a novel mid-level feature learning method for skin lesion classification task is proposed in this paper. In this method, skin lesion segmentation is first performed to detect the regions of interest (ROI) of skin lesion images. Next, pretrained neural networks including ResNet and DenseNet are used as the feature extractors for the ROI images. Instead of using the extracted features directly as input of classifiers, the proposed method obtains the mid-level feature representations by utilizing the relationships among different image samples based on distance metric learning. The learned feature representation is a soft discriminative descriptor, having more tolerance to the hard samples and hence is more robust to the large intra-class difference and inter-class similarity. Experimental results demonstrate advantages of the proposed mid-level features, and the proposed method obtains state-of-the-art performance compared with the existing CNN based methods.

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