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1.
Int J Mol Sci ; 20(18)2019 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-31500376

RESUMO

Accumulating evidence has shown that miR-34a serves as a posttranscriptional regulatory molecule of lipid metabolism in mammals. However, little studies about miR-34a on lipid metabolism in poultry have been reported until now. To gain insight into the biological functions and action mechanisms of miR-34a on hepatic lipid metabolism in poultry, we firstly investigated the expression pattern of miR-34a-5p, a member of miR-34a family, in liver of chicken, and determined its function in hepatocyte lipid metabolism by miR-34a-5p overexpression and inhibition, respectively. We then validated the interaction between miR-34a-5p and its target using dual-luciferase reporter assay, and explored the action mechanism of miR-34a-5p on its target by qPCR and Western blotting. Additionally, we looked into the function of the target gene on hepatocyte lipid metabolism by gain- and loss-of-function experiments. Our results indicated that miR-34a-5p showed a significantly higher expression level in livers in peak-laying hens than that in pre-laying hens. miR-34a-5p could increase the intracellular levels of triglycerides and total cholesterol in hepatocyte. Furthermore, miR-34a-5p functioned by inhibiting the translation of its target gene, long-chain acyl-CoA synthetase 1 (ACSL1), which negatively regulates hepatocyte lipid content. In conclusion, miR-34a-5p could increase intracellular lipid content by reducing the protein level, without influencing mRNA stability of the ACSL1 gene in chickens.

2.
Mol Cancer Ther ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515296

RESUMO

Increased activity of PI3K/AKT/mTOR pathway has been observed in chronic myeloid leukemia (CML). Morin, a kind of flavonoid, exhibits a significant anticancer activity by suppressing the PI3K/AKT signaling pathway. However, the effect of morin on CML and its underlying mechanisms are poorly understood. Here, we found that morin dose-dependently inhibited the proliferation of CML cell lines K562 and KCL22 and induced their apoptosis, with a significant increase in cell apoptosis upon exposure of cells to 50 µM morin. Moreover, morin significantly reduced CML xenograft growth in nude mice. Mechanically, morin attenuated phosphorylated AKT level by upregulating PTEN expression, thus leading to the inhibition of AKT signaling. Knockdown of PTEN by its si-RNA completely abrogated morin-induced cell apoptosis, indicating that PTEN mediates the inductive effect of morin on CML cell apoptosis. More importantly, we found that miR-188-5p was significantly upregulated in CML patients and CML cell lines. Treating CML cells with morin markedly downregulated miR-188-5p expression level. Further, we demonstrated that miR-188-5p repressed PTEN expression by directly targeting its 3'-UTR. miR-188-5p downregulation induced by morin enhanced CML cell apoptosis by relieving miR-188-5p repression of PTEN expression. In summary, morin exerts significant anticancer efficacy in CML by regulating miR-188-5p/PTEN axis and thus repressing the PI3K/AKT signaling.

3.
Zhongguo Zhen Jiu ; 39(9): 1009-12, 2019 Sep 12.
Artigo em Chinês | MEDLINE | ID: mdl-31544393

RESUMO

Xin'an region is enriched in humanities and talents, in which a regional medicine school was generated, named Xin'an medicine. The representative medical scholars have profound knowledge in acupuncture and moxibustion, such as WANG Guo-rui 's theory on "identification the reinforcing from the reducing" and "corresponding between acupoints and needling techniques", WANG Ji 's theory on "moxibustion for heat syndrome and boils and sores" and "selecting optimal points accordingly in treatment", WU Kun's theory on "the same principles shared in acupuncture and herbal medicine" and "the application of five-shu points", ZHENG Mei-jian's innovation about "ZHENG 's three needling technique" and WU Yi-ding's theory on "identifying symptoms/patterns and determining acupoints" and "contraindication of moxibustion". In this paper, the academic thoughts of the Xin'an medical representatives were collected and sorted out on acupuncture and moxibustion and summarized so as to provide the references for further research.

4.
Chaos ; 29(7): 073112, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31370402

RESUMO

In this paper, the reliable synchronization of oscillatory power networks with different topologies is investigated by presenting two simple control strategies, namely, phase feedback control and frequency feedback control. The power networks are modeled by the coupled second-order Kuramoto oscillators that represent both consumers and generators. Through the simulations on the power networks with control, it is found that both the proposed control strategies can effectively enhance the synchronizability of the power networks, except for the case when the frequency feedback strategy is adopted for a coupled power network with the WS structure. In this case, it is observed that the critical coupling strength reaches the smallest value when the feedback control strength is equal to one and a sudden drop of order parameter occurs as the control strength further increases. This work provides innovative ideas for constructing a cost-effective power system.

5.
Sci Rep ; 9(1): 8355, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31175315

RESUMO

The recent rapid development of acoustic logic devices has opened up the possibilities of sound computing and information processing. However, simultaneous realization of acoustic logic devices with subwavelength size, broad bandwidth and passive structure still poses a great challenge. To overcome it, we propose a subwavelength acoustic logic gate which consists of binary-phase passive unit cells placed into a multi-port waveguide. Based on the phase manipulations of the unit cells, we experimentally and numerically realize three basic logic gates OR, NOT and AND, and a composite logic gate XOR with a uniform threshold of 0.4 Pa based on linear acoustic interferences. More importantly, We also design a composite logic gate XNOR by a four-port waveguide, and composite logic gates NOR and NAND and a logic operation A⊙(B+C) based on two logic gates. We demonstrate a 0.6λ-length, 0.3λ-width, and 0.2-fractional bandwidth acoustic logic gate constructed by passive structures, which may lead to important advances in various applications, such as acoustic computing, acoustic information processing and integrated acoustics.

6.
Nat Ecol Evol ; 3(7): 1064-1069, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31209289

RESUMO

Organisms influence ecosystems, from element cycling to disturbance regimes, to trophic interactions and to energy partitioning. Microorganisms are part of this influence, and understanding their ecology in nature requires studying the traits of these organisms quantitatively in their natural habitats-a challenging task, but one which new approaches now make possible. Here, we show that growth rate and carbon assimilation rate of soil microorganisms are influenced more by evolutionary history than by climate, even across a broad climatic gradient spanning major temperate life zones, from mixed conifer forest to high-desert grassland. Most of the explained variation (~50% to ~90%) in growth rate and carbon assimilation rate was attributable to differences among taxonomic groups, indicating a strong influence of evolutionary history, and taxonomic groupings were more predictive for organisms responding to resource addition. With added carbon and nitrogen substrates, differences among taxonomic groups explained approximately eightfold more variance in growth rate than did differences in ecosystem type. Taxon-specific growth and carbon assimilation rates were highly intercorrelated across the four ecosystems, constrained by the taxonomic identity of the organisms, such that plasticity driven by environment was limited across ecosystems varying in temperature, precipitation and dominant vegetation. Taken together, our results suggest that, similar to multicellular life, the traits of prokaryotes in their natural habitats are constrained by evolutionary history to a greater degree than environmental variation.

7.
J Acoust Soc Am ; 145(3): 1331, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31067931

RESUMO

Drug delivery by acoustic waves is a crucial technology for targeted therapy. Recently, a three-layered drug micro-particle was proposed and fabricated, the second shell of which greatly improves both the encapsulation of the drug and the flexibility in its release rate. In this work, the acoustic radiation force (ARF) of an acoustic focused Gaussian beam on a three-layered particle comprising an inner drug core (D), a middle layer of poly(lactide-co-glycolide) (PLGA), and an outer chitosan shell (CS) is investigated. A three-layered elastic shell (TES) mimics the D-PLGA-CS structure, and the acoustic scattering from and ARF of the D-PLGA-CS are studied using Mie theory. This paper focuses on how the geometry and acoustic parameters of the outer shell influence the ARF, finding that the Poisson's ratio of the outer shell affects the ARF more than does the density or Young's modulus. In addition, this paper finds that the choice of the inner drug has little effect on the ARF acting on the D-PLGA-CS particle. The present work may benefit the acoustic manipulation of both TESs and three-layered drugs.

8.
Phys Rev Lett ; 122(19): 193202, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144971

RESUMO

We experimentally investigate the two-dimensional photoelectron momentum spectra of aligned diatomic molecules in an intense laser field. Our results reveal a novel prominent valley structure in the molecular alignment dependence of the high-energy photoelectron spectra along the laser polarization. Resorting to the molecular strong-field approximation and a simple semiclassical analysis, we show that this valley structure stems from the destructive two-center interference of the laser-driven rescattered electrons in diatomic molecules. Based on this two-center interference with aligned diatomic molecules, we demonstrate for the first time a tomographic method to extract the molecular internuclear separation, providing a more straightforward approach of molecular imaging, in comparison with, e.g., laser-induced electron diffraction and fixed-angle broadband laser-driven electron scattering.

9.
ISME J ; 13(9): 2162-2172, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31053828

RESUMO

Relationships between microbial genes and performance are often evaluated in the laboratory in pure cultures, with little validation in nature. Here, we show that genomic traits related to laboratory measurements of maximum growth potential failed to predict the growth rates of bacteria in unamended soil, but successfully predicted growth responses to resource pulses: growth increased with 16S rRNA gene copy number and declined with genome size after substrate addition to soils, responses that were repeated in four different ecosystems. Genome size best predicted growth rate in response to addition of glucose alone; adding ammonium with glucose weakened the relationship, and the relationship was absent in nutrient-replete pure cultures, consistent with the idea that reduced genome size is a mechanism of nutrient conservation. Our findings demonstrate that genomic traits of soil bacteria can map to their ecological performance in nature, but the mapping is poor under native soil conditions, where genomic traits related to stress tolerance may prove more predictive. These results remind that phenotype depends on environmental context, underscoring the importance of verifying proposed schemes of trait-based strategies through direct measurement of performance in nature, an important and currently missing foundation for translating microbial processes from genes to ecosystems.

10.
Biosci Rep ; 39(4)2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30962263

RESUMO

microRNAs (miRNA), as tumor suppressors or oncogenes, are involved in modulating cancer cell behavior, including cell proliferation and apoptosis. The miR-140-5p acts as a tumor suppressor in several tumors, but the role of miR-140-5p in chronic myeloid leukemia (CML) remains unclear. Here, we investigated the suppression of miR-140-5p in CML patients and CML cell lines using quantitative PCR (qPCR) and fluorescence in situ hybridization (FISH). Overexpression miR-140-5p in CML cells significantly inhibited cell proliferation as revealed by the CCK-8 assay and promoted cell apoptosis as revealed by flow cytometry. Moreover, the sine oculis homeobox 1 (SIX1) gene had been confirmed as a direct target of miR-140-5p using bioinformatics analysis and luciferase reporter assays. Overexpression of miR-140-5p decreased the SIX1 protein level in CML cells. SIX1 mRNA and protein levels were significantly up-regulated in CML patients and CML cell lines. Knockdown of SIX1 expression significantly inhibited CML cell proliferation and promoted cell apoptosis. Furthermore, SIX1 as a transcriptional factor positively regulated pyruvate kinase isozyme type M2 (PKM2) expression and played an important role in the Warburg effect. In addition, these findings indicated that miR-140-5p functions as a tumor suppressor and plays a critical role in CML cell apoptosis and metabolism by targeting SIX1. Moreover, the miR-140-5p/SIX1 axis may be a potential therapeutic target in CML.

11.
Cancer Res ; 79(12): 3063-3075, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987997

RESUMO

Cholesterol increases the risk of aggressive prostate cancer and has emerged as a potential therapeutic target for prostate cancer. The functional roles of cholesterol in prostate cancer metastasis are not fully understood. Here, we found that cholesterol induces the epithelial-to-mesenchymal transition (EMT) through extracellular-regulated protein kinases 1/2 pathway activation, which is mediated by EGFR and adipocyte plasma membrane-associated protein (APMAP) accumulation in cholesterol-induced lipid rafts. Mechanistically, APMAP increases the interaction with EGFR substrate 15-related protein (EPS15R) to inhibit the endocytosis of EGFR by cholesterol, thus promoting cholesterol-induced EMT. Both the mRNA and protein levels of APMAP are upregulated in clinical prostate cancer samples. Together, these findings shed light onto an APMAP/EPS15R/EGFR axis that mediates cholesterol-induced EMT of prostate cancer cells. SIGNIFICANCE: This study delineates the molecular mechanisms by which cholesterol increases prostate cancer progression and demonstrates that the binding of cholesterol-induced APMAP with EPS15R inhibits EGFR internalization and activates ERK1/2 to promote EMT. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/12/3063/F1.large.jpg.

12.
Biotechnol Appl Biochem ; 66(4): 545-554, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30990920

RESUMO

Biological mineralization is a highly programmed process in which inorganic minerals reassociate under the strict control of the extracellular matrix to form minerals with special functions and patterns. Shells are biominerals, and their synthesis is finely regulated by organic matrix including matrix proteins, polysaccharides, lipids, pigments, free amino acids, and small peptides. In this study, two matrix protein genes, hic14 and hic19, were isolated from the mantle of the mussel Hyriopsis cumingii. Tissue expression analysis showed that both proteins were expressed mainly in the mantle, and in situ hybridization of mantle tissues showed that they were specifically expressed in the dorsal epithelial cells of mantle pallial. Therefore, hic14 and hic19 were both nacreous layer matrix proteins. In the pearl insertion experiment, hic14 and hic19 kept low expression during pearl sac formation and disordered calcium carbonate deposition, and increased significantly during pearl nacre accumulation, which showed that both proteins participated in the mineralization of pearl nacre. In the RNA interference experiment, shell nacre tablet growth was inhibited after crystal nucleation due to the decreased expression of hic14, and crystal morphology and arrangement of nacre were highly modified after expression of hic19 was inhibited. These results provided further evidence that both hic14 and hic19 participated in nacreous layer biomineralization.

13.
Biosci Biotechnol Biochem ; 83(6): 1045-1061, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30935300

RESUMO

MicroRNAs (miRNAs) regulate the development and growth cycle of hair follicles (HFs). The molecular mechanism by which miRNAs determine the development of HFs in the sheep foetus remains elusive. In this study, the expression profiles of miRNAs at 11 development periods (45, 55, 65, 75, 85, 95, 105, 115, 125, 135 and 145 d) in sheep foetus skin were analysed by high-throughput sequencing and bioinformatics analysis. A total of 72 conserved miRNAs, 44 novel miRNAs and 32 known miRNAs were significantly differentially expressed. qRT-PCR results for 18 miRNAs were consistent with the sequencing data. 85 d of foetal development was the starting point for secondary hair follicle (SF) development according to tissue morphology and cluster analysis. In SF development, the prolactin signalling pathway and platelet activation played important roles, and 10 miRNAs were potential candidate miRNAs in SF initiation.


Assuntos
Desenvolvimento Fetal/genética , Perfilação da Expressão Gênica , Folículo Piloso/crescimento & desenvolvimento , MicroRNAs/genética , Ovinos/embriologia , Animais , Biologia Computacional , Regulação para Baixo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Ativação Plaquetária , Prolactina/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Análise de Sequência de RNA/métodos , Transdução de Sinais , Regulação para Cima ,
14.
Fish Shellfish Immunol ; 89: 437-447, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980916

RESUMO

Proteinase inhibitors with the ability to inhibit specific proteinases are usually closely connected with the immune system. Interestingly, proteinase inhibitors are also a common ingredient in the organic matrix of mollusk shells. However, the molecular mechanism that underlies the role of proteinase inhibitors in immune system and shell mineralization is poorly known. In this study, a Kunitz serine proteinase inhibitor (HcKuPI) was isolated from the mussel Hyriopsis cumingii. HcKuPI was specifically expressed in dorsal epithelial cells of the mantle pallium and HcKuPI dsRNA injection caused an irregular surface and disordered deposition on the aragonite tablets of the nacreous layer. These results indicated that HcKuPI plays a vital role in shell nacreous layer biomineralization. Moreover, the expression pattern of HcKuPI during LPS challenge and pearl formation indicated its involvement in the antimicrobial process during pearl sac formation and nacre tablets accumulation during pearl formation. In the in vitro calcium carbonate crystallization assay, the addition of GST-HcKuPI increased the precipitation rate of calcium carbonate and induced the crystal overgrowth of calcium carbonate. Taken together, these results indicate that HcKuPI is involved in antimicrobial process during pearl formation, and participates in calcium carbonate deposition acceleration and morphological regulation of the crystals during nacreous layer formation. These findings extend our knowledge of the role of proteinase inhibitors in immune system and shell biomineralization.


Assuntos
Antibacterianos/metabolismo , Carbonato de Cálcio/metabolismo , Nácar/metabolismo , Inibidores de Proteases , Unionidae/genética , Unionidae/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Unionidae/metabolismo
15.
Org Biomol Chem ; 17(9): 2379-2383, 2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30724938

RESUMO

K2CO3-catalyzed thio-Michael addition using quinoline-2-thiones and α,ß-unsaturated carbonyl compounds was used to assess the chemoselective construction of C-S and S-S bonds under mild reaction conditions in different solvents. The C-S bond showed a better chemoselective construction in EtOH whereas the S-S bond showed a better chemoselective construction in 1,4-dioxane. The corresponding products, generated from the reaction, presented a significant solvent-controlling effect.

16.
Mar Biotechnol (NY) ; 21(2): 240-249, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30659442

RESUMO

Matrix proteins regulate crystal nucleation, morphology, and polymorphism during pearl biomineralization and have significant correlations with pearl quality traits in nucleated pearls. However, there is little information about the connection between pearl quality traits and matrix proteins in non-nucleated pearls. In this study, we analyzed CaCO3 deposition during the first month of non-nucleated pearl formation and examined the expression patterns of ten shell matrix protein genes (Hcperlucin, hic31, silkmapin, hic22, hic74, hic52, HcTyr, HcCA3, hic24 and Hc-upsalin) in the pearl sac of Hyriopsis cumingii. During pearl formation, CaCO3 crystals were initially deposited in a disorderly manner during days 12 and 15 of pearl formation. On days 18 and 21, CaCO3 crystals gradually nucleated on an organic membrane, and the pattern of crystal deposition changed markedly. Between days 24 and 30, crystals similar to nacre tablets were deposited; they then grew and formed connections in a more orderly fashion, eventually forming the nacreous layer. We observed high expression levels of shell matrix proteins during the phases of disordered or ordered CaCO3 deposition, suggesting they were involved in non-nucleated pearl formation. Furthermore, the expressions of nine matrix proteins were significantly correlated with pearl weight during the first 6 months after grafting. The prismatic-layer matrix protein hic31 and nacreous-layer matrix protein hic22 showed negative correlations with pearl weight, but the other seven nacreous-layer matrix proteins had significantly positive correlations with pearl weight. These results show the involvement of matrix proteins in pearl formation and in determination of quality traits.


Assuntos
Calcificação Fisiológica/genética , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Unionidae/genética , Unionidae/metabolismo , Exoesqueleto/química , Exoesqueleto/metabolismo , Animais , Aquicultura , Carbonato de Cálcio/química , Carbonato de Cálcio/metabolismo , Regulação da Expressão Gênica/fisiologia , Nácar/metabolismo
18.
Biosci Rep ; 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30509961

RESUMO

Lactate dehydrogenase A (LDH-A) is a key enzyme during glycolysis, which increases the synthesis of related proteins and has elevated activity in cancer cells. The role of LDH-A in lung adenocarcinoma (LUAD) progression was investigated in this study. Expression levels of LDH-A were assessed in LUAD samples,and the relationship between LDH-A expression status and the prognosis of LUAD patients was confirmed. The effect of LDH-A on proliferation, invasion, migration, and colony formation of cancer cells was assessed. We further determined the role of LDH-A in tumor growth in   vivo  by using xenograft LUAD tumor models. The potential mechanism of LDH-A promotion in LUAD progression was explored. LDH-A showed an abnormally high expression in LUAD, which is closely associated with poor prognosis in patients with LUAD. In  in vitro  experiments, silencing LDH-A expression in LUAD cells could effectively inhibit proliferation, invasion, migration, and colony formation of cancer cells. In in   vivo  experiments, tumor growth was markedly inhibited by LDH-A silencing in a xenograft model of LUAD. Notably, LDH-A could also promote tumor progression by regulating epithelial-mesenchymal transition (EMT)-related molecules. LDH-A can promote the malignant biological behaviors of LUAD cells, and thus can be a potential target for LUAD treatment.

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