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1.
Nanotechnology ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32059199

RESUMO

In recent years, organic-inorganic hybrid perovskites have attracted wide attention due to their excellent optoelectronic properties in the application of optoelectronic devices. In the manufacturing process of perovskite solar cells, perovskite films inevitably have residual stress caused by non-stoichiometry components and the external load. However, their effects on the structural stability and photovoltaic performance of perovskite solar cells are still not clear. In this work, we investigated the effects of external strain on the structural stability and optoelectronic properties of tetragonal MAPbI3 by using the first-principles calculations. We found that the migration barrier of I- ion increases in the presence of compressive strain and decreases with tensile strain, indicating that the compressive strain can enhance the structural stability of halide perovskites. In addition, the light absorption and electronic properties of MAPbI3 under compressive strain are also improved. The variations of the band gap under triaxial and biaxial strains are consistent within a certain range of strain, resulting from that the band edge positions are mainly influenced by the Pb-I bond in the equatorial plane. Our results provide useful guidance for realizing the commercial applications of MAPbI3-based perovskite solar cells.

2.
Eat Weight Disord ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32026376

RESUMO

PURPOSE: Asprosin is a centrally acting appetite-promoting hormone and promotes glucose production in the liver. This study is the first to investigate the difference in asprosin in the plasma between anorexia nervosa (AN) and healthy controls, and to explore the relationship between asprosin changes and plasma glucose levels and AN symptoms. METHODS: Plasma asprosin and glucose concentrations were detected in AN patients (n = 46) and healthy control subjects (n = 47). Eating Disorder Inventory-2 (EDI-2) was used to assess subjects' eating disorder symptoms and related personality traits. The patient's concomitant levels of depression and anxiety were also measured using the beck depression inventory and beck anxiety inventory, respectively. RESULTS: Results indicate that AN patients had a higher asprosin concentration in their plasma compared to healthy controls (p = 0.033). Among AN patients, plasma asprosin levels correlated positively with EDI-2 interoceptive awareness subscale score (p = 0.030) and negatively with duration of illness (p = 0.036). Multiple linear regression analyses showed that increases in asprosin levels (p = 0.029), glucose levels (p = 0.024) and body mass index (p = 0.003) were associated with an increase of the score of EDI-2 bulimia subscale. CONCLUSIONS: Our findings suggest that the increase in plasma asprosin concentration in patients with AN may be a compensation for the body's energy shortage, and asprosin may be involved in the development of bulimia and lack of interoceptive awareness in AN patients. LEVEL OF EVIDENCE: Level III, case-control analytic study.

3.
Med Image Anal ; 61: 101656, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-32062154

RESUMO

Brain imaging genetics becomes an important research topic since it can reveal complex associations between genetic factors and the structures or functions of the human brain. Sparse canonical correlation analysis (SCCA) is a popular bi-multivariate association identification method. To mine the complex genetic basis of brain imaging phenotypes, there arise many SCCA methods with a variety of norms for incorporating different structures of interest. They often use the group lasso penalty, the fused lasso or the graph/network guided fused lasso ones. However, the group lasso methods have limited capability because of the incomplete or unavailable prior knowledge in real applications. The fused lasso and graph/network guided methods are sensitive to the sign of the sample correlation which may be incorrectly estimated. In this paper, we introduce two new penalties to improve the fused lasso and the graph/network guided lasso penalties in structured sparse learning. We impose both penalties to the SCCA model and propose an optimization algorithm to solve it. The proposed SCCA method has a strong upper bound of grouping effects for both positively and negatively highly correlated variables. We show that, on both synthetic and real neuroimaging genetics data, the proposed SCCA method performs better than or equally to the conventional methods using fused lasso or graph/network guided fused lasso. In particular, the proposed method identifies higher canonical correlation coefficients and captures clearer canonical weight patterns, demonstrating its promising capability in revealing biologically meaningful imaging genetic associations.

4.
EBioMedicine ; 52: 102638, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32014820

RESUMO

BACKGROUND: To improve the early diagnosis of hepatocellular carcinoma (HCC), more effective diagnostic biomarkers are needed. A combination of biomarkers is reported to distinguish individuals with early-stage HCC from at-risk individuals. METHODS: Participants in this study were recruited from six hospitals in China. Literature review was used to choose 19 candidate proteins, a case-control study in the discovery stage was used to identify five proteins (P5) that constituted a diagnostic model. In the training and validation stages, the effectiveness of P5 for detecting early-stage HCC was tested (cross-sectional study). Finally, a nested case-control study independent of the other stages was set up to evaluate the P5 in the preclinical diagnosis of HCC. FINDINGS: Between February 2013 and June 2017, a total of 1396 participants were recruited. A panel of 5 proteins (P5: OPN, GDF15, NSE, TRAP5 and OPG) showed high diagnostic accuracy when differentiating the early-stage HCC from the at-risk group, with AUCs of 0·892, 0·907 and 0·852 for the training stage, validation cohort 1 and cohort 2 data sets, respectively. In the prediction set, the sensitivity of P5 for diagnosing preclinical HCC increased with time, starting from 12 months before to the time of definitive clinical diagnosis (range, 46·15% to 86·67%). INTERPRETATION: The P5 panel has the potential to screen populations at high risk of developing HCC and can enable the early diagnosis of HCC. FUNDING: Research supported by grants from eight funds. All sources of funding were declared at the end of the text.

5.
Brain Connect ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32056450

RESUMO

OBJECTIVE: Hierarchical organization of brain function has been an established concept in the neuroscience field for a long time, however, it has been rarely demonstrated how such hierarchical macroscale functional networks are actually organized in the human brain. In this study, to answer this question, we propose a novel methodology to provide an evidence of evidence on hierarchical organization of functional brain networks. METHOD: This paper introduces the Hybrid Spatiotemporal Deep Learning (HSDL), by jointly using Deep Belief Networks (DBN) and Deep LASSO to reveal the temporal hierarchical features and spatial hierarchical maps of brain networks based on the Human Connectome Project (HCP) 900 fMRI datasets. Briefly, the key idea of HSDL is to extract the weights between two adjacent layers of DBN, which are then treated as the hierarchical dictionaries for Deep LASSO to identify the corresponding hierarchical spatial maps. CONCLUSION: Our results demonstrate that both spatial and temporal aspects of dozens of functional networks exhibit multiscale properties that can be well characterized and interpreted based on existing computational tools and neuroscience knowledge. SIGNIFICANCE: Our proposed novel hybrid deep model is employed to provide the first insightful opportunity to reveal the potential hierarchical organization of time series and functional brain networks, using task-based fMRI signals of human brain.

6.
Nat Commun ; 11(1): 740, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029739

RESUMO

Primary and acquired drug resistance imposes a major threat to achieving optimized clinical outcomes during cancer treatment. Aberrant changes in epigenetic modifications are closely involved in drug resistance of tumor cells. Using BET inhibitor (BETi) resistant leukemia cells as a model system, we demonstrated herein that genome-wide enhancer remodeling played a pivotal role in driving therapeutic resistance via compensational re-expression of pro-survival genes. Capitalizing on the CRISPR interference technology, we identified the second intron of IncRNA, PVT1, as a unique bona fide gained enhancer that restored MYC transcription independent of BRD4 recruitment in leukemia. A combined BETi and CDK7 inhibitor treatment abolished MYC transcription by impeding RNAPII loading without affecting PVT1-mediated chromatin looping at the MYC locus in BETi-resistant leukemia cells. Together, our findings have established the feasibility of targeting enhancer plasticity to overcome drug resistance associated with epigenetic therapies.

7.
Sci Rep ; 10(1): 2485, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051510

RESUMO

Kinases are involved in numerous critical cell signaling processes, and dysregulation in kinase signaling is implicated in many types of human cancers. In this study, we applied a parallel-reaction monitoring (PRM)-based targeted proteomic method to assess kinome reprogramming during melanoma metastasis in three pairs of matched primary/metastatic human melanoma cell lines. Around 300 kinases were detected in each pair of cell lines, and the results showed that Janus kinase 3 (JAK3) was with reduced expression in the metastatic lines of all three pairs of melanoma cells. Interrogation of The Cancer Genome Atlas (TCGA) data showed that reduced expression of JAK3 is correlated with poorer prognosis in melanoma patients. Additionally, metastatic human melanoma cells/tissues exhibited diminished levels of JAK3 mRNA relative to primary melanoma cells/tissues. Moreover, JAK3 suppresses the migration and invasion of cultured melanoma cells by modulating the activities of matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9). In summary, our targeted kinome profiling method provided by far the most comprehensive dataset for kinome reprogramming associated with melanoma progression, which builds a solid foundation for examining the functions of other kinases in melanoma metastasis. Moreover, our results reveal a role of JAK3 as a potential suppressor for melanoma metastasis.

8.
Int J Cancer ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32030746

RESUMO

Lynch syndrome (LS) is the most common hereditary colorectal cancer (CRC) predisposition syndrome. We performed a large-scale study to assess a screening strategy for identifying LS in Chinese CRC patients in routine clinical testing. 4,195 eligible CRCs were universally screened. 8.7% of CRCs were detected with dMMR. The incidence of LS was 2.7% (115 of 4,195) in this cohort; among patients over 70 years of age, only 0.3% (2 of 678) were diagnosed as LS. 17.4% of LS cases showed large genomic deletions/duplications. LS probands developed CRCs predominantly at proximal colon location. The frequency of BRAF V600E mutation among Chinese CRCs was significantly lower than that among Western populations, and MLH1 promoter methylation significantly improved the efficiency of genetic screening for LS among MLH1-deficient patients. A comprehensive molecular testing strategy that includes detection of large genomic rearrangements is imperative for the diagnosis of LS. Among CRC patients aged 70 years or younger, a selective strategy for LS screening might be considered for routine clinical testing. This article is protected by copyright. All rights reserved.

9.
IEEE Trans Cybern ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31985448

RESUMO

In this article, the cooperative control problem is investigated for the nonlinear multiagent system (MAS). For the purpose of avoiding possible data collisions, the stochastic communication protocol (SCP) is adopted to schedule the data transmission at each time instant. To deal with the unmatched disturbances, the composite control strategy is put forward which integrates the model predictive control (MPC) and the integral sliding-mode control methods. The sufficient conditions are established to guarantee the cooperative behavior of the MAS subjected to SCP scheduling. Furthermore, the parameters of the MPC scheme are selected such that the recursive feasibility and mean-square practical stability are guaranteed. Finally, the numerical simulation on the satellites is conducted to verify the effectiveness of the proposed methodology.

10.
Brain Imaging Behav ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31950404

RESUMO

Mapping the relation between cortical convolution and structural/functional brain architectures could provide deep insights into the mechanisms of brain development, evolution and diseases. In our previous studies, we found a unique gyral folding pattern, termed a 3-hinge, which was defined as the conjunction of three gyral crests. The uniqueness of the 3-hinge was evidenced by its thicker cortex and stronger fiber connections than other gyral regions. However, the role that 3-hinges play in cortico-cortical connective architecture remains unclear. To this end, we conducted MRI studies by constructing structural cortico-cortical connective networks based on a fine-granular cortical parcellation, the parcels of which were automatically labeled as 3-hinge, 2-hinge (ordinary gyrus) or sulcus. On human brains, 3-hinges possess significantly higher degrees, strengths and betweennesses than 2-hinges, suggesting that 3-hinges could serve more like hubs in the cortico-cortical connective network. This hypothesis gains supports from human functional network analyses, in which 3-hinges are involved in more global functional networks than ordinary gyri. In addition, 3-hinges could serve as 'connector' hubs rather than 'provincial' hubs and they account for a dominant proportion of nodes in the high-level 'backbone' of the network. These structural results are reproduced on chimpanzee and macaque brains, while the roles of 3-hinges as hubs become more pronounced in higher order primates. Our new findings could provide a new window to the relation between cortical convolution, anatomical connection and brain function.

11.
Mar Drugs ; 18(1)2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31936139

RESUMO

Mycosporine-like amino acids (MAAs), maximally absorbed in the wavelength region of 310-360 nm, are widely distributed in algae, phytoplankton and microorganisms, as a class of possible multi-functional compounds. In this work, based on the Web of Science, Springer, Google Scholar, and China national knowledge infrastructure (CNKI), we have summarized and analyzed the studies related to MAAs in marine macroalgae over the past 30 years (1990-2019), mainly focused on MAAs distribution, contents, and types. It was confirmed that 572 species marine macroalgae contained MAAs, namely in 45 species of Chlorophytes, 41 species of Phaeophytes, and 486 species of Rhodophytes, and they respectively belonged to 28 orders. On this basis, we established an open online database to quickly retrieve MAAs in 501 species of marine macroalgae. Furthermore, research concerning MAAs in marine macroalgae were analyzed using CiteSpace. It could easily be seen that the preparation and purification of MAAs in marine macroalgae have not been intensively studied during the past 10 years, and therefore it is necessary to strengthen the research in the preparation and purification of MAA purified standards from marine macroalgae in the future. We agreed that this process is not only interesting, but important due to the potential use of MAAs as food and cosmetics, as well as within the medicine industry.

12.
J Cardiothorac Surg ; 15(1): 21, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941543

RESUMO

BACKGROUND: The present study aimed to evaluate the value of admission serum uric acid (UA) level in predicting in-hospital risk of death in patients with acute type A aortic dissection (AAAD). METHODS: From January 2016 to June 2019, 186 consecutive patients with AAAD who underwent thoracic aortic surgery were retrospectively studied. Serum UA levels were measured on admission. Forward conditional logistic regression was performed to identify independent risk factors for in-hospital death. Receiver operating characteristic (ROC) analysis was performed to assess the most clinical useful level of serum UA for predicting postoperative in-hospital mortality. RESULTS: Increased level of serum UA was found in non-survivors compared with those survived (446 ± 123 vs 371 ± 111 umol/L, p < 0.001). Age (OR = 1.063, 95% CI 1.016-1.112, p = 0.009), UA (OR = 1.006, 95% CI 1.002-1.010, p = 0.002), D-dimer (OR = 1.025, 95% CI 1.005-1.013, p = 0.012), operation time (OR = 1.009, 95% CI 1.005-1.013, p < 0.001) and extent of aortic replacement (OR = 0.412, 95% CI 0.220-0.768, p = 0.005) were identified as independent risk factors of in-hospital mortality in AAAD patients. The best cut-off value of admission serum UA in predicting in-hospital mortality was determined to be 415 umol/L. Subgroup analysis showed that in the subgroup of total arch replacement, UA was significantly associated with in-hospital death (OR = 1.010, 95% CI 1.005-1.015, p < 0.001), while in patients underwent ascending aorta replacement or hemiarch replacement, the relationship was no longer significant (OR = 1.001, 95% CI 0.996-1.006, p = 0.611). CONCLUSIONS: Elevated serum UA level on admission is an independent predictor of in-hospital mortality in patients with AAAD.

13.
Nanotechnology ; 31(16): 165504, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-31899903

RESUMO

Cu3(PO4)2 flowers are reported for the first time as a solid precursor for the preparation of hierarchical CuO particles with sea urchin-like morphology in the absence of self-assembled templates or matrixes. In the alkaline condition, Cu3(PO4)2 transforms into Cu(OH)2 firstly, and then into CuO through dehydration at room temperature. Different from soluble Cu salt as precursor, the basic building blocks for CuO are continuously supplied in a controlled manner form Cu3(PO4)2 precursor, which ensures a nearly sustained supersaturated concentration that favors heterogeneous nucleation and progressive growth of sea urchin-like CuO particles. The gas sensing property of as-prepared sea urchin-like CuO particles to ethanol is investigated. The sea urchin-like CuO particles exhibit a good sensing performance in terms of high response, short response/recovery time, good selectivity, good reproducibility, and long-term stability. The facile strategy demonstrated here opens up a new strategy to fabricate hierarchical CuO particles with enormous potential from the perspective of practical application.

14.
Methods Mol Biol ; 2102: 195-210, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31989556

RESUMO

RNA interference (RNAi) is a powerful approach for inhibiting gene expression and its wide applications have expanded our understanding of gene functions. Short hairpin RNAs (shRNAs) are artificially synthesized RNA molecules used to mediate RNAi. The expression of shRNA in cells can be achieved by using plasmids or viral/bacterial vectors. The use of viral vectors to carry and deliver shRNA shows many advantages, including the ability to overcome the difficulty of transfecting certain cell types, the capability to establish stable cell lines via antibiotics selection or fluorescence-activated cell sorting, and the option to control temporally shRNA expression using inducible promoters. In this chapter, we introduce a gene silencing method utilizing a lentivirus-based inducible shRNA system. Using the human topoisomerase (TOP) gene as an example, we describe a procedure to generate stable HepG2 cells showing inducible suppression of TOP1. In addition, a procedure for assessing the efficiency of gene silencing is described in detail.

15.
Methods Mol Biol ; 2102: 531-555, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31989575

RESUMO

Endoplasmic reticulum (ER) stress is one of the major mechanisms underlying the etiology of multiple diseases and drug-induced toxicity. Gaussia luciferase (Gluc) is a naturally secreted protein that has been used as a reporter for the secretory pathway of ER to enable efficient and real-time monitoring of the ER function. The Gluc assay has been widely used and optimized in various labs. In this chapter, we provide an example of the application of the Gluc assay by establishing a stable cell line expressing both Gluc and firefly luciferase (Fluc) to study ER stress in liver cells. We describe the detailed procedures used in our laboratory for Gluc- and Fluc-containing lentivirus production and titration, for establishing a HepG2-based stable cell line through lentivirus transduction and the validation process. In addition, we provide an example of using the established stable cell line to investigate ER stress.

16.
Methods Mol Biol ; 2102: 557-566, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31989576

RESUMO

microRNAs (miRNAs) modulate the expression of enzymes responsible for activation or detoxification of xenobiotics and toxicants. miRNAs are dysregulated in response to environmental exposure and have been implicated in toxicological events. Many in vivo and in vitro experimental approaches have been employed to delineate the mechanisms by which miRNAs regulate target genes; however, all these methods provide only indirect evidence for the interaction between miRNAs and their counterpart mRNA molecules. In this chapter, we describe a novel approach-a fluorescent-based RNA electrophoretic mobility shift assay (FREMSA) that is a sensitive and time-saving method, with a high specificity, to visualize the interactions among miRNAs, mRNAs, and proteins, as direct evidence of mRNA/miRNA complex formation.

17.
Chem Commun (Camb) ; 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31994547

RESUMO

Adjusting the position of active components is critical to enhancing the activity of CHA structured small-pore zeolites for NO selective catalytic reduction. We herein synthesized a novel low-cost multi-metal Cu-Ce-La-SSZ-13 catalyst via a simple one-pot method and revealed the relationship between the position of active species and catalytic activity. The introduction of Ce4+ ions and La3+ ions can effectively regulate the Cu2+ cations to migrate from eight-membered rings to more active six-membered rings, which endows Cu-Ce-La-SSZ-13 with excellent low-temperature SCR activity.

18.
Nat Prod Res ; : 1-7, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31960725

RESUMO

A new phenol derivative, 3-chloro-5-hydroxy-4-methoxyphenylacetic acid methyl ester (1), along with five known compounds methyl 4-hydroxyphenylacetate (2), cytosporone B (3), (R)-striatisporolide A (4), (R)-butanedioic acid (5) and ergosterol (6) were isolated from the mangrove-derived fungus Eupenicillium sp. HJ002. Their structures were established by spectroscopic methods, GIAO based 13C NMR chemical shift calculations and comparison with the data of literature. Compounds 1-5 were isolated from Xylocarpus granatum Koening-derived fungus for the first time.

19.
Mar Drugs ; 18(1)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963874

RESUMO

Five new perylenequinone derivatives, altertoxins VIII-XII (1-5), as well as one known compound cladosporol I (6), were isolated from the fermentation broth of the marine-derived fungus Cladosporium sp. KFD33 from a blood cockle from Haikou Bay, China. Their structures were determined based on spectroscopic methods and ECD spectra analysis along with quantum ECD calculations. Compounds 1-6 exhibited quorum sensing inhibitory activities against Chromobacterium violaceum CV026 with MIC values of 30, 30, 20, 30, 20 and 30 µg/well, respectively.

20.
Zool Res ; 41(1): 20-31, 2020 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-31930784

RESUMO

There is a growing appreciation for the specific health benefits conferred by commensal microbiota on their hosts. Clinical microbiota analysis and animal studies in germ-free or antibiotic-treated mice have been crucial for improving our understanding of the role of the microbiome on the host mucosal surface; however, studies on the mechanisms involved in microbiome-host interactions remain limited to small animal models. Here, we demonstrated that rhesus monkeys under short-term broad-spectrum antibiotic treatment could be used as a model to study the gut mucosal host-microbiome niche and immune balance with steady health status. Results showed that the diversity and community structure of the gut commensal bacteria in rhesus monkeys were both disrupted after antibiotic treatment. Furthermore, the 16S rDNA amplicon sequencing results indicated that Escherichia-Shigella were predominant in stool samples 9 d of treatment, and the abundances of bacterial functional genes and predicted KEGG pathways were significantly changed. In addition to inducing aberrant morphology of small intestinal villi, the depletion of gut commensal bacteria led to increased proportions of CD3 + T, CD4 + T, and CD16 + NK cells in peripheral blood mononuclear cells (PBMCs), but decreased numbers of Treg and CD20 + B cells. The transcriptome of PBMCs from antibiotic-treated monkeys showed that the immune balance was affected by modulation of the expression of many functional genes, including IL-13, VCAM1, and LGR4.


Assuntos
Disbiose/imunologia , Microbioma Gastrointestinal , Intestinos/anatomia & histologia , Macaca mulatta/microbiologia , Animais , Antibacterianos/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , DNA Bacteriano/genética , Fezes/microbiologia , Intestinos/microbiologia , Masculino
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