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1.
J Food Sci ; 2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32418198

RESUMO

Radioresistance is an important factor affecting the radiotherapy effect of colorectal cancer (CRC). Allicin is a versatile sulfur-containing organic compound extracted from garlic (Allium sativum L.), which has many pharmacological effects. However, the effect of allicin on the sensitivity of CRC radiotherapy has not been confirmed. The present study is to observe the radiosensitivity effects of allicin and to explore its mechanism in CRC radiotherapy. The proliferation inhibition effects of allicin combined with X-ray radiotherapy in HCT116 cells were measured by growth curve of cell and colony formation assays. The cell apoptosis was detected by Hoechst 33258 nucleus staining assay. The migration ability of cells was detected by Transwell chamber migration assay. The animal model of CRC was established in BALB/c mice via transplantation of CT26 cell, and the radiosensitization effect of allicin on CRC was detected in vivo. The mRNA expressions of NF-κB, IKKß, and IκBα were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). The protein expressions of NF-κB, p-NF-κB, IKKß, p-IKKß, IκBα, and p-IκBα were detected by western blotting. Our results showed that allicin improves the sensitivity of X-ray radiotherapy in CRC, and its mechanism may be associated with inhibition of NF-κB signaling pathway. These findings suggest that allicin may be used as a potential sensitizer for tumor radiotherapy in the clinic.

2.
Theranostics ; 10(9): 3849-3866, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32226524

RESUMO

In the past decade, the study of exosomes, nanosized vesicles (50-150 nm) released into the extracellular space via the fusion of multivesicular bodies with the plasma membrane, has burgeoned with impressive achievements in theranostics applications. These nanosized vesicles have emerged as key players in homeostasis and in the pathogenesis of diseases owing to the variety of the cargos they can carry, the nature of the molecules packaged inside the vesicles, and the robust interactions between exosomes and target cells or tissues. Accordingly, the development of exosome-based liquid biopsy techniques for early disease detection and for monitoring disease progression marks a new era of precision medicine in the 21st century. Moreover, exosomes possess intrinsic properties - a nanosized structure and unique "homing effects" - that make them outstanding drug delivery vehicles. In addition, targeted exosome-based drug delivery systems can be further optimized using active targeting ligands such as nucleic acid aptamers. Indeed, the aptamers themselves can function as therapeutic and/or diagnostic tools based on their attributes of unique target-binding and non-immunogenicity. This review aims to provide readers with a current picture of the research on exosomes and aptamers and their applications in cancer theranostics, highlighting recent advances in their transition from the bench to the clinic.

3.
Sci Total Environ ; 715: 136805, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32041038

RESUMO

Aryl hydrocarbon receptor (AhR) plays important roles in the interferences of dioxin exposure with the occurrence and development of tumors. Neuroblastoma is a kind of malignant tumor with high mortality and its occurrence is getting higher in dioxin exposed populations. However, there is still a lack of direct evidence of influences of dioxin on neuroblastoma cell migration. SK-N-SH is a human neuroblastoma cell line which has been used to reveal 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced dysregulation of certain promigratory gene. Thus, in this study, we employed SK-N-SH cells to investigate the effects of TCDD on the spontaneous movement of neuroblastoma cells, which is a short-range cell migratory behavior related to clone formation and tumor metastasis in vitro. Using unlabeled live cell imaging and high content analysis, we characterized the spontaneous movement under a full-nutrient condition in SK-N-SH cells. We found that the spontaneous movement of SK-N-SH cells was inhibited after 36- or 48-h treatment with TCDD at relative low concentrations (10-10 or 2 × 10-10 M). The TCDD-treated cells were unable to move as freely as that of control cells, resulting in less diffusive trajectories and a decreased displacement of the movement. In line with this cellular effect, the expression of pro-adhesive genes was significantly induced in time- and concentration-dependent manners after TCDD treatment. In addition, with the presence of AhR antagonist, CH223191, the effects of TCDD on the gene expression and the spontaneous cell movement were effectively reversed. Thus, we proposed that AhR-mediated up-regulation of pro-adhesive genes might be involved in the inhibitory effects of dioxin on the spontaneous movement of neuroblastoma cells. To our knowledge, this is the first piece of direct evidence about the influence of dioxin on neuroblastoma cell motility.


Assuntos
Neuroblastoma , Movimento Celular , Células Cultivadas , Expressão Gênica , Humanos , Dibenzodioxinas Policloradas , Receptores de Hidrocarboneto Arílico
4.
Artigo em Inglês | MEDLINE | ID: mdl-31944647

RESUMO

High power conversion efficiency (PCE) and long-term stability are inevitable issues faced in practical device applications of perovskite solar cells. In this paper, significant enhancements in the device efficiency and stability are achieved by using a surface-active lead acetate (Pb(OAc)2) at the top or bottom of CH3NH3PbI3 (MAPbI3)-based perovskite. When a saturated Pb(OAc)2 solution is introduced on the top of the MAPbI3 perovskite precursor, the OAc- in Pb(OAc)2 participates in lattice restructuring of MAPbI3 to form MAPbI3-x(OAc)x, thereby producing a high-quality perovskite film with high crystallinity, large grain sizes, and uniform and pinhole-free morphology. Moreover, when Pb(OAc)2 solution is mixed in the poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) solution in the bottom way, the OAc- in Pb(OAc)2 improves the water resistance of PEDOT-PSS. As the OAc- easily bonds with the Pb2+, the deposition of MAPbI3 precursor onto the Pb(OAc)2 mixed with PEDOT-PSS results in a reduction of the uncoordinated Pb, leading to strong stabilization of the perovskite layer. Both the top- and bottom-treated devices exhibit enhanced PCE values of 18.93% and 18.28%, respectively, compared to the conventional device with a PCE of 16.47%, which originates from decreased trap sites and reduced energy barriers. In particular, the bottom-treated device exhibits long-term stability, with more than 84% of its initial PCE over 800 h in an ambient environment.

5.
J Biol Chem ; 294(52): 19889-19895, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31753916

RESUMO

N 6-Methyladenosine (m6A) is the most abundant post-transcriptional mRNA modification in eukaryotes and exerts many of its effects on gene expression through reader proteins that bind specifically to m6A-containing transcripts. Fragile X mental retardation protein (FMRP), an RNA-binding protein, has previously been shown to affect the translation of target mRNAs and trafficking of mRNA granules. Loss of function of FMRP causes fragile X syndrome, the most common form of inherited intellectual disability in humans. Using HEK293T cells, siRNA-mediated gene knockdown, cytoplasmic and nuclear fractions, RNA-Seq, and LC-MS/MS analyses, we demonstrate here that FMRP binds directly to a collection of m6A sites on mRNAs. FMRP depletion increased mRNA m6A levels in the nucleus. Moreover, the abundance of FMRP targets in the cytoplasm relative to the nucleus was decreased in Fmr1-KO mice, an effect also observed in highly methylated genes. We conclude that FMRP may affect the nuclear export of m6A-modified RNA targets.

6.
Environ Sci Technol ; 53(21): 12803-12811, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31566365

RESUMO

Field investigations have revealed the ability of the climbing perch Anabas testudineus to survive in highly contaminated water bodies. The aryl hydrocarbon receptor (AhR) pathway is vital in mediating the toxicity of aromatic hydrocarbon contaminants, and genotypic variation in the AhR can confer resistance to these contaminants. Thus, we characterized the AhR pathway in A. testudineus in order to understand the mechanism(s) underlying the resistance of this species to contaminants and to broaden current knowledge on teleost AhR. In A. testudineus, four AhRs, two AhR nuclear translocators (ARNTs), and one AhR repressor (AhRR) were found. Transient transfection assays revealed that AhR1a, AhR1b, and AhR2b were functional, whereas AhR2a was poorly activated by the potent agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Two ARNTs (partner of AhR) and one AhRR (repressor of AhR) all were functional with each of the active AhR. As a major form, the insensitivity of AhR2a might serve as a potential mechanism for A. testudineus' reduced sensitivity to severe contamination. We explored the key residues that may account for AhR2a's insensitivity in silico and then functionally validated them in vitro. Two sites (VCS322-324, M370) in its ligand-binding domain (LBD) were proved critical for its sensitivity to TCDD. This systematic exploration of the AhR pathway showed that most members have maintained their traditional functions as expected, whereas a nonfunctionalization event has occurred for AhR2a.


Assuntos
Dibenzodioxinas Policloradas , Receptores de Hidrocarboneto Arílico , Animais , Peixes
7.
J Food Sci ; 84(9): 2658-2665, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31441515

RESUMO

Hepatic injury is one of the most common digestive system diseases worldwide in clinic. Guanylic acid or guanosine monophosphate (GMP) was an important component of nucleotides, which is mainly in the form of sodium salt (disodium guanylate, GMP-Na2 ). However, its effect on hepatic injury has not yet been investigated. This study is to investigate the protective effects of GMP-Na2 on acute hepatic injury induced by carbon tetrachloride (CCl4 ), and to explore its mechanism. The hepatic injury models of mice and HL-7702 cells were induced by CCl4 . The alanine transaminase (ALT), aspartate aminotransferase (AST), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), total antioxidant capacity (T-AOC) were determined by biochemical method. Hematoxylin-eosin staining were used to determine the morphological changes on liver tissue in mice. The mRNA and protein expressions of caspase-3, Bax, and Bcl-2 were detected by RT-PCR and Western blot analysis. Our results show that GMP-Na2 treatment significantly decreased the activities of ALT and AST, and the levels of MDA as well as increased the levels of SOD, GSH-Px, and T-AOC. Importantly, GMP-Na2 effectively enhanced the antiapoptosis function by upregulating Bcl-2 expression and downregulating caspase-3 and Bax expressions in vivo and in vitro. Moreover, the histopathological changes of liver tissue were obviously improved after GMP-Na2 treatment. These findings suggest that GMP-Na2 has protective effects on hepatic injury, and its mechanisms may be associated with antioxidative stress and antiapoptosis.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Guanosina Monofosfato/farmacologia , Fígado/efeitos dos fármacos , Animais , Fígado/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos
8.
Cell Rep ; 28(4): 845-854.e5, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340148

RESUMO

N6-methyladenosine (m6A) modification of mRNA is emerging as a vital mechanism regulating RNA function. Here, we show that fragile X mental retardation protein (FMRP) reads m6A to promote nuclear export of methylated mRNA targets during neural differentiation. Fmr1 knockout (KO) mice show delayed neural progenitor cell cycle progression and extended maintenance of proliferating neural progenitors into postnatal stages, phenocopying methyltransferase Mettl14 conditional KO (cKO) mice that have no m6A modification. RNA-seq and m6A-seq reveal that both Mettl14cKO and Fmr1KO lead to the nuclear retention of m6A-modified FMRP target mRNAs regulating neural differentiation, indicating that both m6A and FMRP are required for the nuclear export of methylated target mRNAs. FMRP preferentially binds m6A-modified RNAs to facilitate their nuclear export through CRM1. The nuclear retention defect can be mitigated by wild-type but not nuclear export-deficient FMRP, establishing a critical role for FMRP in mediating m6A-dependent mRNA nuclear export during neural differentiation.

9.
Sci Total Environ ; 687: 516-526, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31216508

RESUMO

Polyhalogenated carbazoles (PHCZs) are a class of contaminants identified with persistence and bioaccumulation property from previous studies. However, the toxic effect and mechanism of PHCZs are not fully understood. In this study, eleven PHCZs, including four chlorocarbazoles, four bromocarbazoles and two bromo/chlorocarbazoles were screened for their potential aryl hydrocarbon receptor (AhR) activity by using a dioxin responsive element-driven luciferase reporter assay. We found that nine PHCZs significantly activated AhR in a concentration-dependent manner. Their potencies of AhR activation were 1000 to 100,000 folds less than that of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most potent AhR ligand. The relative AhR activation potency of the nine PHCZs followed the order 2,3,6,7-tetrachloro-9H-carbazole >2,7-dibromo-9H-carbazole >1,3,6-tribromo-9H-carbazole >1,3,6,8-tetrachloro-9H-carbazole >1,3,6,8-tetrabromo-9H-carbazole >1-bromo-3,6-dichloro-9H-carbazole >3,6-dibromo-9H-carbazole >3-bromo-9H-carbazole >1,8-dibromo-3,6-dichloro-9H-carbazole, which was partly in line with the induction of AhR-mediated CYP1A1 expression. In silico analysis indicated that the nine PHCZs could be docked into the same pocket as TCDD due to their high structural similarity. However, the shrunk size of the heterocyclic moieties in PHCZs relative to that in TCDD dramatically decreased the complex stability provided by inter-molecular interactions. Moreover, two distinguished docking poses adopted by the nine PHCZs were found, in which one was illustrated by 2367-CCZ and 27-BCZ while the other symbolized by TCDD and the left seven agonists. The differential antagonizing effects of CH223191 on PHCZ-induced AhR activity supported such pose differentiation. The present experimental and in silico data provide new direct evidence of PHCZ-AhR interaction which sheds light on AhR-associated toxicological study and risk assessment of PHCZs.

10.
Front Genet ; 10: 410, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130987

RESUMO

Spinal muscular atrophy (SMA) is a severe motor neuron degenerative disease caused by loss-of-function mutations in the survival motor neuron gene SMN1. It is widely posited that defective gene expression underlies SMA. However, the identities of these affected genes remain to be elucidated. By analyzing the transcriptome of a Caenorhabditis elegans SMA model at the pre-symptomatic stage, we found that the expression of numerous nuclear encoded mitochondrial genes and vacuolar H+-ATPase genes was significantly down-regulated, while that of histone genes was significantly up-regulated. We previously showed that the uaf-1 gene, encoding key splicing factor U2AF large subunit, could affect the behavior and lifespan of smn-1 mutants. Here, we found that smn-1 and uaf-1 interact to affect the recognition of 3' and 5' splice sites in a gene-specific manner. Altogether, our results suggest a functional interaction between smn-1 and uaf-1 in affecting RNA splicing and a potential effect of smn-1 on the expression of mitochondrial and histone genes.

11.
J Cell Biochem ; 120(9): 15157-15169, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31111564

RESUMO

BACKGROUND: Long noncoding RNA urothelial carcinoma-associated 1 (lncRNA-UCA1) is generally recognized as an oncogenic molecule in several human malignant tumors. However, the available evidence does not necessarily imply an unequivocal causal function of UCA1 in glioblastoma. The current study was aimed to probe the biological function of lncRNA-UCA1 in human glioblastoma cell lines. Besides, we further investigated the potential mechanisms. METHODS: Cell viability, apoptosis, as well as migration and invasion were measured using a commercial cell counting kit-8, flow cytometry, and 24-Transwell assay, respectively. LncRNA-UCA1, microRNA-193a (miR-193a), and CDK6 at messenger RNA levels were evaluated by quantitative real-time polymerase chain reaction method. Protein level was examined by Western blot analysis. RNA immunoprecipitation was utilized to validate lncRNA-UCA1 associated with miR-193a. Luciferase activity assay was used to identify the miR-193a-targeted CDK6 3'-untranslated region. RESULTS: lncRNA-UCA1 knockdown weakened cell viability, augmented apoptosis progression, as well as suppressed migration and invasion behaviors in glioblastoma cells, whereas lncRNA-UCA1 silence exhibited the opposite functions. lncRNA-UCA1 functioned as an endogenous sponge of miR-193a. miR-193a silence reversed the biological function of lncRNA-UCA1 knockdown on U-118 MG cells. miR-193a negatively regulated the expression of CDK6, and it affected the U-118 MG cells through regulating CDK6 expression. CDK6 overexpression abrogated the blockage of PI3K/AKT, mitogen-activated protein kinase (MAPK), and Notch signaling pathways. Furthermore, lncRNA-UCA1 and miR-193a could affect these signaling cascades through regulating CDK6 expression. The regulatory mechanisms of lncRNA-UCA1 were further consolidated in clinical specimens. CONCLUSION: lncRNA-UCA1 silence reduced cell viability, promoted apoptosis progression, while impeding the migration and invasion of glioblastoma cells by miR-193a-mediated silence of CDK6, with blockage of PI3K/AKT, MAPK, and Notch pathways.

12.
Chem Biol Interact ; 308: 164-169, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31100272

RESUMO

Emerging data indicate that prenatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) could interfere with myogenic differentiation in vivo. Acetylcholinesterase (EC3.1.1.7; AChE), an enzyme critical for cholinergic neurotransmission, is abundantly expressed in neurons and mature myotubes, and we recently found that muscle AChE expression was suppressed in parallel with the inhibition of myogenic differentiation upon TCDD treatment in mouse C2C12 cells. This TCDD-induced suppression of muscle AChE was proposed to involve an aryl hydrocarbon receptor (AhR)-independent mechanism, but the precise underlying mechanism remains unclear. Considering the widely recognized role of muscular activity in AChE expression and its potential crosstalk with the AhR signaling pathway, we sought to investigate the effect of TCDD on muscle AChE expression in the presence of muscular activity. Therefore, we employed a highly contractile rat primary skeletal muscle culture system in which AChE activity and the expression of genes related to it (AChE T subunit and collagen Q (ColQ)) were increased during the myogenic differentiation process. Although TCDD treatment successfully induced the expression of genes regulated by AhR activation, the treatment exerted no notable effects on myogenic differentiation. Moreover, muscle AChE enzymatic activity and mRNA level remained unchanged following TCDD treatment, and only ColQ mRNA expression was slightly increased after 4-day treatment with TCDD (10-10 M). The compensatory role of muscle-contraction-related signaling pathways in this newly identified unresponsiveness of muscle AChE to TCDD warrants further investigation.


Assuntos
Acetilcolinesterase/metabolismo , Diferenciação Celular/efeitos dos fármacos , Desenvolvimento Muscular/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Acetilcolinesterase/genética , Animais , Células Cultivadas , Colágeno/genética , Colágeno/metabolismo , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Contração Muscular/efeitos dos fármacos , Mioblastos Esqueléticos/citologia , Mioblastos Esqueléticos/efeitos dos fármacos , Mioblastos Esqueléticos/metabolismo , Dibenzodioxinas Policloradas/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
13.
Nanomaterials (Basel) ; 9(3)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823644

RESUMO

Constructing elaborate catalysts to prompt the charge carrier separation and transport is critical to developing efficient photocatalytic systems. Here, a hierarchical hollow structure based on 1D/2D BiOCl/Bi2WO6 hybrid materials was fabricated by a precursor chemical engineering method. This hybrid is made up of molten 1D BiOCl nanorods and 2D Bi2WO6 nanosheets. The synergetic effect of the presence of BiOCl and specific interfaces between BiOCl and Bi2WO6 provided efficient interfacial charge transfer of photogenerated carriers under visible light. Seamless BiOCl functions like a noble metal, with platinum-like behavior, accelerating the oxidizing ability of fabricated BiOCl/Bi2WO6 hybrids, which was favorable for the photocatalytic decomposition of organic compounds (3.2 times greater for Rhodamine B (RhB) and 4 times greater for Ciprofloxacin (CIP)) over the Bi2WO6 catalysts. The beneficial interfacial interaction between BiOCl and Bi2WO6 resulting from the unique construction prompted the charge transfer from the conduction band of Bi2WO6 to that of BiOCl. The findings presented in this study provide a cost-effective precursor-mediated strategy to realize the critical and efficient separation of photoinduced carriers in environmental remediation applications.

14.
J Bioinform Comput Biol ; 17(6): 1940012, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-32019414

RESUMO

Mapping short reads to a reference genome is an essential step in many next-generation sequencing (NGS) analyses. In plants with large genomes, a large fraction of the reads can align to multiple locations of the genome with equally good alignment scores. How to map these ambiguous reads to the genome is a challenging problem with big impacts on the downstream analysis. Traditionally, the default method is to assign an ambiguous read randomly to one of the many potential locations. In this study, we explore two alternative methods that are based on the hypothesis that the possibility of an ambiguous read being generated by a location is proportional to the total number of reads produced by that location: (1) the enrichment method that assigns an ambiguous read to the location that has produced the most reads among all the potential locations, (2) the probability method that assigns an ambiguous read to a location based on a probability proportional to the number of reads the location produces. We systematically compared the performance of the proposed methods with that of the default random method. Our results showed that the enrichment method produced better results than the default random method and the probability method in the discovery of single nucleotide polymorphisms (SNPs). Not only did it produce more SNP markers, but it also produced SNP markers with better quality, which was demonstrated using multiple mainstay genomic analyses, including genome-wide association studies (GWAS), minor allele distribution, population structure, and genomic prediction.

15.
PLoS One ; 13(12): e0208104, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30507965

RESUMO

The process of rice domestication has been studied for decades based on changing morphological characteristics in assemblages of both macroremains, such as charred seeds and spikelet bases, and microremains, such as phytoliths, esp. bulliform and double-peaked phytoliths. The applicability of these indicators in determining if a specific assemblage is wild or domesticated, however, is rarely discussed. To understand the significance of these indicators in the determination of domestication, we collected 38 archaeological samples from eight Neolithic sites, dating from 10-2ka BP, in the lower Yangtze River region to analyze and compare the changes of these different indicators over eight thousand years. The data demonstrate that the comprehensive analysis of multiple indicators may be the best method to study the process of rice domestication developed thus far. An assemblage of rice remains can be identified as domesticated forms if they meet the following criteria simultaneously: 1) the proportion of domesticated-type bulliform phytoliths is more than 73%; and 2) the proportion of domesticated-type rice spikelet bases is higher than 75%. Furthermore, we found that each indicator tends to change steadily and gradually over time, and each stabilized at a different time, suggesting that the characteristics of domesticated rice developed slowly and successively. Changes of multiple indicators during the period between 10,000-2,000 yr BP indicate that the process of rice domestication in the lower Yangtze River region lasted as long as ca. 6,000 years during the Neolithic, and can be divided into three stages with the turning points in the middle Hemudu-late Majiabang culture (6,500-5,800yr BP) and the late Liangzhu culture (4,600-4,300yr BP).


Assuntos
Domesticação , Grão Comestível/história , Fósseis , Oryza/anatomia & histologia , Sementes/anatomia & histologia , Arqueologia , China , Grão Comestível/anatomia & histologia , História Antiga , Rios
16.
Nanoscale ; 11(1): 170-177, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30525145

RESUMO

The crystallization of MAPbI3 perovskite films was purposefully engineered to investigate the governing factors which determine their morphological properties and moisture stability. By modulating nucleation, we obtained a single layer perovskite film with controlled crystal facet orientation and grain size. The lack of perovskite nucleation sites during crystallization allowed us to tailor the resulting crystallization phase. Theoretical calculations indicated that the nucleation sites for perovskite growth are related to the electron density around the oxygen atom (C[double bond, length as m-dash]O and S[double bond, length as m-dash]O) in a Lewis base. A single layer of micrometer-sized and (110)-oriented perovskite crystals was achieved in the optimized MAPbI3 films via suppressing the formation of nucleation sites. We fabricated inverted perovskite solar cells with the structure of glass/ITO/PEDOT:PSS/MAPbI3/PC61BM/Al which exhibited a high power conversion efficiency of 17.5% and a high fill factor over 83%. In addition, a study of the moisture stability indicated that the (110) facet orientation of the perovskite grains plays a more important role in film degradation than grain size.

17.
RNA Biol ; 15(10): 1295-1308, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30295127

RESUMO

A key step in pre-mRNA splicing is the recognition of 3' splicing sites by the U2AF large and small subunits, a process regulated by numerous trans-acting splicing factors. How these trans-acting factors interact with U2AF in vivo is unclear. From a screen for suppressors of the temperature-sensitive (ts) lethality of the C. elegans U2AF large subunit gene uaf-1(n4588) mutants, we identified mutations in the RNA binding motif gene rbm-5, a homolog of the tumor suppressor gene RBM5. rbm-5 mutations can suppress uaf-1(n4588) ts-lethality by loss of function and neuronal expression of rbm-5 was sufficient to rescue the suppression. Transcriptome analyses indicate that uaf-1(n4588) affected the expression of numerous genes and rbm-5 mutations can partially reverse the abnormal gene expression to levels similar to that of wild type. Though rbm-5 mutations did not obviously affect alternative splicing per se, they can suppress or enhance, in a gene-specific manner, the altered splicing of genes in uaf-1(n4588) mutants. Specifically, the recognition of a weak 3' splice site was more susceptible to the effect of rbm-5. Our findings provide novel in vivo evidence that RBM-5 can modulate UAF-1-dependent RNA splicing and suggest that RBM5 might interact with U2AF large subunit to affect tumor formation.


Assuntos
Processamento Alternativo/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Neoplasias/genética , Proteínas de Ligação a RNA/genética , Ribonucleoproteínas/genética , Proteínas Supressoras de Tumor/genética , Animais , Animais Geneticamente Modificados/genética , Caenorhabditis elegans/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Humanos , Mutação , Neoplasias/patologia , Neurônios/metabolismo , Sítios de Splice de RNA/genética , Processamento de RNA/genética , Fator de Processamento U2AF/genética , Temperatura
18.
ACS Appl Mater Interfaces ; 10(37): 31366-31373, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30152673

RESUMO

Perovskite optoelectronic devices are being regarded as future candidates for next-generation optoelectronic devices. Device performance has been shown to be influenced by the perovskite film, which is determined by the grain size, surface roughness, and film coverage; therefore, developing controllable and highly crystalline perovskite films is pivotal for highly efficient devices. In this work, an innovative bulk heterojunction (BHJ)-assisted grain growth (BAGG) technique was developed to accurately control the quality of perovskite films. By a simple modulation of the polymer-to-PC61BM ratio in the BHJ film, the transition to a complete film phase from the perovskite precursor was accurately regulated, resulting in a controllable perovskite grain growth and high-quality final perovskite film. Moreover, because the BHJ layer could seep deeply into the perovskite active layer through the grain boundaries in the BAGG process, it facilitated the interface engineering and charge transport. The perovskite solar cells containing an optimized CH3NH3PbI3 film presented a high efficiency of 18.38% and fill factor of 83.71%. The perovskite light-emitting diode that contained a nanoscale and uniform CH3NH3PbBr3 film with full coverage presented enhanced emission properties with a brightness value of 1600 cd/m2 at 6.0 V and a luminous efficiency of 0.56 cd/A.

19.
Nanoscale ; 10(20): 9628-9633, 2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29756134

RESUMO

A cost-effective fabrication method that can produce a remarkable enhancement in the device efficiency along with a reduction in the fabrication cost is one of the crucial requirements for the commercialization of perovskite-based solar cells. Here, we report a low-cost, printable, and highly effective synchronized-pressing annealing (SPA) method for inverted planar perovskite solar cells. In this method, two films are combined face-to-face for annealing, and separated as in a roll-to-roll process. Consequently, the SPA method provides two homogeneous highly crystalline MAPbI3 films with monolithic millimeter-scale crystalline grains by intermediate-induced crystallization engineering. The grains present a tendency of oriented growth along the <110> direction, parallel to the substrate, which leads to efficient charge transport. The IPSCs fabricated by the SPA method demonstrate a high efficiency of ∼17% with significantly enhanced photocurrents and fill factors. Moreover, the characteristics of both top and bottom devices are very similar, with nearly identical J-V curves and photoresponse spectra. As the SPA method is compatible with the printing technology for mass production, and as it can produce twin devices of high quality via one fabrication process, it can provide a remarkable reduction in the fabrication cost.

20.
Pediatr Res ; 83(1-2): 258-266, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28915233

RESUMO

Pediatric patients with a neurogenic urinary bladder, caused by developmental abnormalities including spina bifida, exhibit chronic urological problems. Surgical management in the form of enterocystoplasty is used to enlarge the bladder, but is associated with significant clinical complications. Thus, alternative methods to enterocystoplasty have been explored through the incorporation of stem cells with tissue engineering strategies. Within the context of this review, we will examine the use of bone marrow stem cells and induced pluripotent stem cells (iPSCs), as they relate to bladder regeneration at the anatomic and molecular levels. The use of bone marrow stem cells has demonstrated significant advances in bladder tissue regeneration as multiple aspects of bladder tissue have been recapitulated including the urothelium, bladder smooth muscle, vasculature, and peripheral nerves. iPSCs, on the other hand, have been well characterized and used in multiple tissue-regenerative settings, yet iPSC research is still in its infancy with regards to bladder tissue regeneration with recent studies describing the differentiation of iPSCs to the bladder urothelium. Finally, we examine the role of the Sonic Hedgehog signaling cascade that mediates the proliferative response during regeneration between bladder smooth muscle and urothelium. Taken together, this review provides a current, comprehensive perspective on bladder regeneration.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Medicina Regenerativa/métodos , Engenharia Tecidual , Bexiga Urinaria Neurogênica/terapia , Bexiga Urinária/patologia , Animais , Células da Medula Óssea/citologia , Diferenciação Celular , Proteínas Hedgehog/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Músculo Liso , Fenótipo , Regeneração , Transdução de Sinais , Disrafismo Espinal/terapia , Transplante de Células-Tronco , Tecidos Suporte , Urotélio/fisiologia
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