Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 250
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Genet Epidemiol ; 48(1): 42-55, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38014869

RESUMO

Rare-variants (RVs) genetic association studies enable researchers to uncover the variation in phenotypic traits left unexplained by common variation. Traditional single-variant analysis lacks power; thus, researchers have developed various methods to aggregate the effects of RVs across genomic regions to study their collective impact. Some existing methods utilize a static delineation of genomic regions, often resulting in suboptimal effect aggregation, as neutral subregions within the test region will result in an attenuation of signal. Other methods use varying windows to search for signals but often result in long regions containing many neutral RVs. To pinpoint short genomic regions enriched for disease-associated RVs, we developed a novel method, DYNamic Aggregation TEsting (DYNATE). DYNATE dynamically and hierarchically aggregates smaller genomic regions into larger ones and performs multiple testing for disease associations with a controlled weighted false discovery rate. DYNATE's main advantage lies in its strong ability to identify short genomic regions highly enriched for disease-associated RVs. Extensive numerical simulations demonstrate the superior performance of DYNATE under various scenarios compared with existing methods. We applied DYNATE to an amyotrophic lateral sclerosis study and identified a new gene, EPG5, harboring possibly pathogenic mutations.


Assuntos
Variação Genética , Árvores , Humanos , Modelos Genéticos , Estudos de Associação Genética , Mutação , Estudo de Associação Genômica Ampla/métodos , Proteínas Relacionadas à Autofagia , Proteínas de Transporte Vesicular
2.
Nat Mater ; 22(1): 73-83, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36456873

RESUMO

Achieving the long-term stability of perovskite solar cells is arguably the most important challenge required to enable widespread commercialization. Understanding the perovskite crystallization process and its direct impact on device stability is critical to achieving this goal. The commonly employed dimethyl-formamide/dimethyl-sulfoxide solvent preparation method results in a poor crystal quality and microstructure of the polycrystalline perovskite films. In this work, we introduce a high-temperature dimethyl-sulfoxide-free processing method that utilizes dimethylammonium chloride as an additive to control the perovskite intermediate precursor phases. By controlling the crystallization sequence, we tune the grain size, texturing, orientation (corner-up versus face-up) and crystallinity of the formamidinium (FA)/caesium (FA)yCs1-yPb(IxBr1-x)3 perovskite system. A population of encapsulated devices showed improved operational stability, with a median T80 lifetime (the time over which the device power conversion efficiency decreases to 80% of its initial value) for the steady-state power conversion efficiency of 1,190 hours, and a champion device showed a T80 of 1,410 hours, under simulated sunlight at 65 °C in air, under open-circuit conditions. This work highlights the importance of material quality in achieving the long-term operational stability of perovskite optoelectronic devices.


Assuntos
Amidinas , Luz Solar , Cátions , Dimetil Sulfóxido
3.
Ann Surg Oncol ; 31(2): 1232-1242, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37930500

RESUMO

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) constitutes a group of heterogeneous malignancies within the liver. We sought to subtype ICC based on anatomical origin of tumors, as well as propose modifications of the current classification system. METHODS: Patients undergoing curative-intent resection for ICC, hilar cholangiocarcinoma (CCA), or hepatocellular carcinoma (HCC) were identified from three international multi-institutional consortia of databases. Clinicopathological characteristics and survival outcomes were assessed. RESULTS: Among 1264 patients with ICC, 1066 (84.3%) were classified as ICC-peripheral subtype, whereas 198 (15.7%) were categorized as ICC-perihilar subtype. Compared with ICC-peripheral subtype, ICC-perihilar subtype was more often associated with aggressive tumor characteristics, including a higher incidence of nodal metastasis, macro- and microvascular invasion, perineural invasion, as well as worse overall survival (OS) (median: ICC-perihilar 19.8 vs. ICC-peripheral 37.1 months; p < 0.001) and disease-free survival (DFS) (median: ICC-perihilar 12.8 vs. ICC-peripheral 15.2 months; p = 0.019). ICC-perihilar subtype and hilar CCA had comparable OS (19.8 vs. 21.4 months; p = 0.581) and DFS (12.8 vs. 16.8 months; p = 0.140). ICC-peripheral subtype tumors were associated with more advanced tumor features, as well as worse survival outcomes versus HCC (OS, median: ICC-peripheral 37.1 vs. HCC 74.3 months; p < 0.001; DFS, median: ICC-peripheral 15.2 vs. HCC 45.5 months; p < 0.001). CONCLUSIONS: ICC should be classified as ICC-perihilar and ICC-peripheral subtype based on distinct clinicopathological features and survival outcomes. ICC-perihilar subtype behaved more like carcinoma of the bile duct (i.e., hilar CCA), whereas ICC-peripheral subtype had features and a prognosis more akin to a primary liver malignancy.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Colangiocarcinoma/patologia , Prognóstico , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia
4.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34341109

RESUMO

Unlike crystalline atomic and ionic solids, texture development due to crystallographically preferred growth in colloidal crystals is less studied. Here we investigate the underlying mechanisms of the texture evolution in an evaporation-induced colloidal assembly process through experiments, modeling, and theoretical analysis. In this widely used approach to obtain large-area colloidal crystals, the colloidal particles are driven to the meniscus via the evaporation of a solvent or matrix precursor solution where they close-pack to form a face-centered cubic colloidal assembly. Via two-dimensional large-area crystallographic mapping, we show that the initial crystal orientation is dominated by the interaction of particles with the meniscus, resulting in the expected coalignment of the close-packed direction with the local meniscus geometry. By combining with crystal structure analysis at a single-particle level, we further reveal that, at the later stage of self-assembly, however, the colloidal crystal undergoes a gradual rotation facilitated by geometrically necessary dislocations (GNDs) and achieves a large-area uniform crystallographic orientation with the close-packed direction perpendicular to the meniscus and parallel to the growth direction. Classical slip analysis, finite element-based mechanical simulation, computational colloidal assembly modeling, and continuum theory unequivocally show that these GNDs result from the tensile stress field along the meniscus direction due to the constrained shrinkage of the colloidal crystal during drying. The generation of GNDs with specific slip systems within individual grains leads to crystallographic rotation to accommodate the mechanical stress. The mechanistic understanding reported here can be utilized to control crystallographic features of colloidal assemblies, and may provide further insights into crystallographically preferred growth in synthetic, biological, and geological crystals.

5.
Zhongguo Zhong Yao Za Zhi ; 49(2): 518-533, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403327

RESUMO

The efficacy and safety of different Chinese patent medicines in the treatment of coronary heart disease complicated with heart failure were evaluated by network Meta-analysis. The randomized controlled trial(RCT) of Chinese patent medicines for coronary heart disease complicated with heart failure was retrieved from CNKI, Wanfang, VIP, SinoMed, PubMed, Web of Science, EMbase, and Cochrane Library with the time interval from inception to July 5, 2023. The quality of the included RCT was evaluated by the Cochrane's risk of bias assessment tool, and a network Meta-analysis was performed in Stata 16.0. Finally, a total of 82 RCTs were included, involving 9 298 patients and 11 Chinese patent medicines. Network Meta-analysis yielded the following results based on the surface under the cumulative ranking curve(SUCRA).(1)In terms of improving the clinical response rate, the top three interventions were Qishen Yiqi Dripping Pills + conventional western medicine, Zhenyuan Capsules + conventional western medicine, and Tongxinluo Capsules + conventional western medicine.(2) In terms of increasing left ventricular ejection fraction(LVEF), the top three interventions were Shexiang Baoxin Pills + conventional western medicine, Compound Danshen Dripping Pills + conventional western medicine, and Tongxinluo Capsules + conventional western medicine.(3) In terms of reducing left ventricular end-diastolic diameter(LVEDD), the top three interventions were Shexiang Tongxin Dripping Pills + conventional western medicine, Tongxinluo Capsules + conventional western medicine, and Shexiang Baoxin Pills + conventional western medicine.(4) In terms of reducing N-terminal pro-brain natriuretic peptide(NT-proBNP), the top three interventions were Shexiang Baoxin Pills + conventional western medicine, Qi-shen Yiqi Dripping Pills + conventional western medicine, and Compound Danshen Dripping Pills + conventional western medicine.(5) In terms of reducing hyper-sensitive C-reactive protein(hs-CRP), the top three interventions were Naoxintong Capsules + conventional western medicine, Shexiang Baoxin Pills + conventional western medicine, and Compound Danshen Dripping Pills + conventional western medicine.(6) In terms of increasing the distance of the six-minute walking trail(6MWT), the top three interventions were Zhen-yuan Capsules + conventional western medicine, Qili Qiangxin Capsules + conventional western medicine, and Qishen Yiqi Dripping Pills + conventional western medicine. The results showed that Chinese patent medicines combined with conventional western medicine can effectively improve the clinical response rate, LVEF, and 6MWT and reduce LVEDD, NT-proBNP, and hs-CRP. However, due to the overall low quality of the articles included and the few articles of some Chinese patent medicines, direct comparison between diffe-rent Chinese patent medicines remains to be carried out and the results need to be further verified.


Assuntos
Doença das Coronárias , Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Humanos , Metanálise em Rede , Medicamentos sem Prescrição/uso terapêutico , Proteína C-Reativa , Volume Sistólico , Função Ventricular Esquerda , Medicamentos de Ervas Chinesas/uso terapêutico , Doença das Coronárias/complicações , Doença das Coronárias/tratamento farmacológico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico
6.
Small ; 19(43): e2301822, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37386817

RESUMO

Excess lead iodide (PbI2 ) aggregation at the charge carrier transport interface leads to energy loss and acts as unstable origins in perovskite solar cells (PSCs). Here, a strategy is reported to modulate the interfacial excess PbI2 by introducing π-conjugated small-molecule semiconductors 4,4'-cyclohexylbis[N,N-bis(4-methylphenyl)aniline] (TAPC) into perovskite films through an antisolvent addition method. The coordination of TAPC to PbI units through the electron-donating triphenylamine groups and π-Pb2+ interactions allows for a compact perovskite film with reduced excess PbI2 aggregates. Besides, preferred energy level alignment is achieved due to the suppressed n-type doping effect at the hole transport layer (HTL) interfaces. As a result, the TAPC-modified PSC based on Cs0.05 (FA0.85 MA0.15 )0.95 Pb(I0.85 Br0.15 )3 triple-cation perovskite achieved an improved PCE from 18.37% to 20.68% and retained ≈90% of the initial efficiency after 30 days of aging under ambient conditions. Moreover, the TAPC-modified device based on FA0.95 MA0.05 PbI2.85 Br0.15 perovskite produced an improved efficiency of 23.15% compared to the control (21.19%). These results provide an effective strategy for improving the performance of PbI2 -rich PSCs.

7.
Langmuir ; 39(31): 10779-10787, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37498111

RESUMO

Antireflective (AR) films are widely applied in solar cells to reduce the reflectivity toward sunlight, thus improving the photoelectric conversion efficiency (PCE) of solar cells. However, AR films are still suffering from poor mechanical properties and low transmittance in photovoltaic applications. Herein, a ZrO2-SiO2 composite film with enhanced mechanical properties was successfully synthesized by a facile sol-gel method, whose pencil hardness increased from less than 6B to B compared with the pure SiO2 film synthesized with the same alkali-catalyzed method. Moreover, the ZrO2-SiO2 film with a Zr/Si mole ratio (nZr/Si) of 0.06 exhibited a high transmittance gain (ΔT) of 3.0%, and an obvious increase (1.32%) in PCE was observed in a perovskite solar cell compared with the cell covered by a bare glass. Additionally, both the short-circuit current density (JSC) and PCE of perovskite solar cells have a non-linear increasing relationship with the average transmittance (Tavg) of the ZrO2-SiO2 composite film. In this sense, this work can provide a facile way to prepare AR films effectively improving performances of solar cells.

8.
BMC Pregnancy Childbirth ; 23(1): 828, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036952

RESUMO

BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP) is a prevalent pregnancy-specific complication that presents with maternal itching and elevated serum bile acid levels. ICP is associated with unfavorable pregnancy outcomes, severely decreasing the pregnant woman's quality of life. Timely identification of ICP is crucial for effective management and improved outcomes. METHODS: We collected urine samples from 8 patients with ICP and 8 healthy individuals. We used Liquid Chromatography-Mass Spectrometry (LC-MS) to detect metabolite expression levels, then conducted a series of bioinformatic analyses to explore the potential biological meanings of differentially expressed metabolites, and preliminarily discovered several candidate biomarkers. To validate these candidate biomarkers, we performed Gas Chromatography-Mass Spectrometry (GC-MS) detection and analyzed their diagnostic values using receiver operating characteristic (ROC) curve. RESULTS: Untargeted metabolomics data showed that 6129 positive peaks and 6218 negative peaks were extracted from each specimen. OPLS-DA analysis and the heat map for cluster analysis showed satisfactory capability in discriminating ICP specimens from controls. Subsequent analysis extracted 64 significantly differentially expressed metabolites, which could be potential biomarkers for diagnosis of ICP. Based on the KEGG enrichment analyses, six candidate biomarkers were preliminarily identified. Two most promising biomarkers (3-hydroxypropionic acid and uracil) were validated by targeted metabolomics analyses with the area under the curve (AUC) of 0.920 and 0.850 respectively. CONCLUSION: Based on preliminary screening from untargeted metabolomics and subsequent validation through targeted metabolomics, 3-hydroxypropionic acid and uracil were identified as promising diagnostic biomarkers for ICP.


Assuntos
Colestase Intra-Hepática , Qualidade de Vida , Gravidez , Feminino , Humanos , Metabolômica , Colestase Intra-Hepática/diagnóstico , Biomarcadores , Uracila
9.
Biotechnol Lett ; 45(8): 993-1000, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37243776

RESUMO

The self-sufficient cytochrome P450 BM3 mutant (A74G/F87V/D168H/L188Q) can serve as a biocatalyst for whole-cell catalysis process of indigo. Nevertheless, the bioconversion yield of indigo is generally low under normal cultivation conditions (37 °C, 250 rpm). In this study, a recombinant E. coli BL21(DE3) strain was constructed to co-express the P450 BM3 mutant gene and GroEL/ES genes to investigate whether GroEL/ES can promote the indigo bioconversion yield in E. coli. The results revealed that the GroEL/ES system could significantly increase the indigo bioconversion yield, and the indigo bioconversion yield of the strain co-expressing P450 BM3 mutant and GroEL/ES was about 21-fold that of the strain only expressing the P450 BM3 mutant. In addition, the P450 BM3 enzyme content and in vitro indigo bioconversion yield were determined to explore the underlying mechanism for the improvement of indigo bioconversion yield. The results revealed that GroEL/ES did not increase indigo bioconversion yield by increasing the content of P450 BM3 enzyme and its enzymatic transformation efficiency. Moreover, GroEL/ES could improve the intracellular nicotinamide adenine dinucleotide phosphate (NADPH)/NADP+ ratio. Given that NADPH is an important coenzyme in the catalytic process of indigo, the underlying mechanism for the improvement of indigo bioconversion yield is probably related to an increase in the intracellular NADPH/NADP+ ratio.


Assuntos
Escherichia coli , Índigo Carmim , Escherichia coli/genética , Escherichia coli/metabolismo , NADP/metabolismo , NADPH-Ferri-Hemoproteína Redutase/genética , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Proteínas de Bactérias/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Biotransformação
10.
Sensors (Basel) ; 23(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37420527

RESUMO

Infrared images have been widely used in many research areas, such as target detection and scene monitoring. Therefore, the copyright protection of infrared images is very important. In order to accomplish the goal of image-copyright protection, a large number of image-steganography algorithms have been studied in the last two decades. Most of the existing image-steganography algorithms hide information based on the prediction error of pixels. Consequently, reducing the prediction error of pixels is very important for steganography algorithms. In this paper, we propose a novel framework SSCNNP: a Convolutional Neural-Network Predictor (CNNP) based on Smooth-Wavelet Transform (SWT) and Squeeze-Excitation (SE) attention for infrared image prediction, which combines Convolutional Neural Network (CNN) with SWT. Firstly, the Super-Resolution Convolutional Neural Network (SRCNN) and SWT are used for preprocessing half of the input infrared image. Then, CNNP is applied to predict the other half of the infrared image. To improve the prediction accuracy of CNNP, an attention mechanism is added to the proposed model. The experimental results demonstrate that the proposed algorithm reduces the prediction error of the pixels due to full utilization of the features around the pixel in both the spatial and the frequency domain. Moreover, the proposed model does not require either expensive equipment or a large amount of storage space during the training process. Experimental results show that the proposed algorithm had good performances in terms of imperceptibility and watermarking capacity compared with advanced steganography algorithms. The proposed algorithm improved the PSNR by 0.17 on average with the same watermark capacity.


Assuntos
Redes Neurais de Computação , Análise de Ondaletas , Algoritmos , Registros , Segurança Computacional
11.
Zhongguo Zhong Yao Za Zhi ; 48(16): 4508-4520, 2023 Aug.
Artigo em Zh | MEDLINE | ID: mdl-37802877

RESUMO

This study reviewed the current status of the use of outcome indicators in randomized controlled trial(RCT) on traditional Chinese medicine(TCM) treatment of microvascular angina(MVA) and analyzed the existing problems and possible solutions, aiming to provide a basis for the design of high-quality RCT and the establishment of core outcome sets for MVA. CNKI, Wanfang, VIP, SinoMed, PubMed, EMbase, Cochrane Library, Web of Science, and 2 clinical trial registries were searched for the RCT on TCM treatment of MVA according to pre-defined criteria. The Cochrane's risk of bias assessment tool was used to evaluate the methodological quality of the included RCT and the use of outcome indicators was summarized. A total of 69 RCTs were included, from which 100 outcome indicators were extracted, with the frequency of 430. The extracted outcome indicators belonged to 8 domains: response rate, symptoms and signs, physical and chemical examinations, TCM efficacy, safety, quality of life, economic evaluation, and long-term prognosis. The indicators of physical and chemical examinations were the most(70 indicators with the frequency of 211), followed by those of response rate(7 indicators with the frequency of 73) and symptoms and signs(7 indicators with the frequency of 54). The outcome indicators with higher frequency were adverse reactions, angina attack frequency, clinical efficacy, endothelin-1, total duration of treadmill exercise, and hypersensitive C-reactive protein. The RCT on TCM treatment of MVA had the following problems: irregular reporting of adverse reactions, diverse indicators with low frequency, lack of attention to the application of endpoint indicators, insufficient use of TCM differentiation and efficacy indicators, non-standard evaluation criteria and failure to reflect the basic characteristics of TCM. A unified MVA syndrome differentiation standard should be established, on the basis of which an MVA treatment efficacy evaluation system and core outcome indicator set that highlights the characteristics of TCM with patient-reported outcomes as the starting point should be established to improve the clinical research and research value.


Assuntos
Medicamentos de Ervas Chinesas , Angina Microvascular , Humanos , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/efeitos adversos , Angina Microvascular/tratamento farmacológico , Qualidade de Vida , Fitoterapia , Resultado do Tratamento
12.
Nature ; 594(7861): 27-28, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34079131
13.
Sensors (Basel) ; 22(20)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36298196

RESUMO

Deep learning has become an essential technique in image steganography. Most of the current deep-learning-based steganographic methods process digital images in the spatial domain. There are problems such as limited embedding capacity and unsatisfactory visual quality. To improve capacity-distortion performance, we develop a steganographic method from the frequency-domain perspective. We propose a module called the adaptive frequency-domain channel attention network (AFcaNet), which makes full use of the frequency features in each channel by a fine-grained manner of assigning weights. We apply this module to the state-of-the-art SteganoGAN, forming an Adaptive Frequency High-capacity Steganography Generative Adversarial Network (AFHS-GAN). The proposed neural network enhances the ability of high-dimensional feature extraction through overlaying densely connected convolutional blocks. In addition to this, a low-frequency loss function is introduced as an evaluation metric to guide the training of the network and thus reduces the modification of low-frequency regions of the image. Experimental results on the Div2K dataset show that our method has a better generalization capability compared to the SteganoGAN, with substantial improvement in both embedding capacity and stego-image quality. Furthermore, the embedding distribution of our method in the DCT domain is more similar to that of the traditional method, which is consistent with the prior knowledge of image steganography.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação
14.
J Chem Phys ; 154(16): 161101, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33940857

RESUMO

We present a computational approach to simulate linear sweep and cyclic voltammetry experiments that does not require a discretized grid in space to quantify diffusion. By using a Green's function solution coupled to a standard implicit ordinary differential equation solver, we are able to simulate current and redox species concentrations using only a small grid in time. As a result, where benchmarking is possible, we find that the current method is faster than (and quantitatively identical to) established techniques. The present algorithm should help open the door for studying adsorption effects in inner sphere electrochemistry.

15.
Nano Lett ; 20(2): 1240-1251, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31960676

RESUMO

3D/2D hybrid perovskite systems have been intensively investigated to improve the stability of perovskite solar cells (PSCs), whereas undesired crystallization of 2D perovskite during the film formation process could undermine the structural stability of 2D perovskite materials, which causes serious hysteresis of PSCs after aging. This issue is, however, rarely studied. The stability study for 3D/2D hybrid systems to date is all under the one-direction scan, and the lack of detailed information on the hysteresis after aging compromises the credibility of the stability results. In this work, by correlating the hysteresis of the hybrid PSCs with the 2D crystal structure, we find that the prompt 2D perovskite formation process easily induces numerous crystal imperfections and structural defects. These defects are susceptible to humidity attack and decompose the 2D perovskite to insulating long-chain cations and 3D perovskite, which hinder charge transfer or generate charge accumulation. Therefore, a large hysteresis is exhibited after aging the 3D/2D hybrid PSCs in an ambient environment, even though the reverse-scan power conversion efficiency (PCE) is found to be well-preserved. To address this issue, alkali cations, K+ and Rb+, are introduced into the 2D perovskite to exquisitely modulate the crystal formation, which gives rise to a higher crystallinity of 2D perovskite and a better film morphology with fewer defects. We achieved PCE beyond 21% due to the preferable charge transfer process and reduced nonradiative recombination losses. The structural features also bring about impressive moisture stability, which results in the corresponding PSCs retaining 93% of its initial PCE and negligible hysteresis after aging in an ambient atmosphere for 1200 h.

16.
Opt Express ; 28(9): 12650-12660, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403758

RESUMO

Back-contact architectures for perovskite solar cells eliminate parasitic-absorption losses caused by the electrode and charge collection layers but increase surface reflection due to the high refractive index mismatch at the air/perovskite interface. To mitigate this, a ∼85 nm thick layer of poly(methyl methacrylate) (PMMA), with a refractive index between those of air and perovskite, has been applied as an antireflective coating. Transfer matrix modelling is used to determine the ideal PMMA layer thickness, with UV-Vis spectroscopy measurements used to confirm the increase in absorption that arises through the application of the antireflective coating. The deposition of a thin film of PMMA via spin coating onto a solar cell results in a 20-30% relative increase in short circuit current density and stable power output density.

17.
Med Sci Monit ; 26: e919241, 2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31955177

RESUMO

BACKGROUND This study aimed to investigate the expression of microRNA-639 (miR-639) in tumor tissue from patients with hepatocellular carcinoma (HCC) and its effects on patient outcome, to identify the targets for miR-639 using bioinformatics and luciferase reporter analysis, and the effects of miR-639 in human HCC cells in vitro to identify the molecular pathways involved. MATERIAL AND METHODS Expression levels of miR-639 were compared in tumor tissue and adjacent normal liver tissue from 50 patients with HCC, and Kaplan-Meier curves identified the association with overall survival (OS). miR-639 expression was measured in HCC cells cultured in vitro using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and Western blot. HCC cells were studied using the MTT assay, the colony formation assay, and the transwell assay. Bioinformatics and luciferase reporter analysis identified the role of the histone acetyltransferase gene, KAT7, in HCC. RESULTS The expression of miR-639 was significantly reduced in HCC tissues compared with normal adjacent liver tissues, and inhibited cell proliferation and epithelial-mesenchymal transition (EMT) of HCC cells. Bioinformatics and luciferase reporter analysis showed that miR-639 directly targeted KAT7 and inhibit its expression. KAT7 expression promoted cell proliferation, and migration of human HCC cells in vitro, and miR-639 inhibited cell proliferation and EMT by down-regulating the KAT7/Wnt/ß-catenin signaling pathway. CONCLUSIONS miR-639 was down-regulated in HCC tumor tissue, and inhibited proliferation and migration of HCC cells by the down-regulation of KAT7/Wnt/ß-catenin signaling and was associated with reduced OS. These findings supported the potential role of miR-639 as a tumor suppressor.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular/genética , Regulação para Baixo/genética , Histona Acetiltransferases/metabolismo , Neoplasias Hepáticas/genética , MicroRNAs/genética , Via de Sinalização Wnt/genética , Regiões 3' não Traduzidas/genética , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Análise de Sobrevida
18.
Adv Exp Med Biol ; 1217: 349-362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31898237

RESUMO

Protein neddylation is one type of posttranslational modifications that regulates the activity of the substrate proteins. Neddylation modification is catalyzed by NEDD8-activating enzyme (NAE, E1), NEDD8-conjugating enzyme (E2), and NEDD8 ligase (E3) to attach NEDD8, an ubiquitin-like molecule, to a lysine residue of a substrate protein. The best known neddylation substrates are cullin family members, which are scaffold components of cullin-RING ligases (CRLs), and cullin neddylation is required for activation of CRLs. In mammalian cells, there are one E1, two E2s (UBC12/UBE2M and UBE2F), and over a dozen E3s. MLN4924, the first-in-class small-molecule inhibitor of NAE, blocks the entire neddylation modification to inactivate activity of all CRLs. MLN4924 is currently in the Phase I/II clinical trials for anticancer application.In the last few years, targeting protein-protein interactions of the neddylation complexes has been pursued as a potential strategy to selectively inhibit the activity of individual CRL. Analysis of the co-crystal structures of DCN1, a co-E3 for neddylation, and its binding partners UBC12 (a neddylation E2) suggested that it may be amenable for the design of potent, small-molecule inhibitors. In this chapter, we will review the discovery of small-molecule inhibitors that block the interactions of DCN1 with UBC12 (hereafter called DCN1 inhibitors) from a number of laboratories, including ours, leading to selective inactivation of CRL-1 and/or CRL-3. We will also discuss potential therapeutic applications of these small-molecule inhibitors.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína NEDD8/metabolismo , Ligação Proteica/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Enzimas de Conjugação de Ubiquitina/metabolismo , Animais , Humanos
19.
Pharmazie ; 75(10): 500-504, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33305725

RESUMO

The etiology of osteoarthritis (OA) has been discussed widely, but the molecular mechanisms beneath OA aggravation have not yet been investigated in detail. This study focused on the role of lncRNA RMRP (RMRP) on OA progression. We found that the expression of RMRP was significantly increased in cartilage tissues of patients with OA. CCK-8 and colony formation assays showed that RMRP knockdown promoted proliferation of chondrocytes treated with IL-1ß. Flow cytometry and caspase-3 activity analysis indicated that RMRP silence inhibited apoptosis of chondrocytes treated with IL-1ß. Moreover, luciferase reporter, RNA pull-down and RIP assays showed that RMRP competing with miR-206. Additionally, CDK9 acted as a direct target of miR-206. Moreover, rescue assays indicated that miR-206 inhibitor or pcDNA-CDK9 reversed the effects of RMRP suppression on the proliferation and apoptosis of chondrocytes. Taken together, our results indicated that RMRP knockdown could promote proliferation and inhibit apoptosis in OA chondrocytes via the miR-206/CDK9 axis.


Assuntos
Condrócitos/patologia , MicroRNAs/genética , Osteoartrite/patologia , RNA Longo não Codificante/genética , Apoptose/genética , Cartilagem/patologia , Linhagem Celular , Proliferação de Células/genética , Quinase 9 Dependente de Ciclina/genética , Progressão da Doença , Técnicas de Silenciamento de Genes , Humanos , Interleucina-1beta/administração & dosagem , Osteoartrite/genética
20.
Anal Chem ; 91(15): 9747-9753, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31283180

RESUMO

Facile and efficient assembly of intelligent DNA nano-objects with the ability to exert robust microRNA determination is essential for DNA nanobiotechnology and basic biomedical study. Herein, we present a novel target-triggered DNA assembly pathway for the construction of multibranched DNA nanoarchitectures by the combination of DNA concatamers with G-quadruplex wires. The DNA concatamers acting as the main body structures were assembled by hybridization chain reaction (HCR), while the G-quadruplex wires acting as the branch structures were generated by terminal deoxynucleotidyl transferase (TdT)-promoted polymerization and G-quadruplex units (GUs) based self-assembly. With a copious number of G-quadruplex replicates collected on the electrode surface, the obtained multibranched DNA nanoarchitectures were able to bind with lots of hemin, which further led to a significantly amplified electrochemical sensing signal for ultrasensitive and selective detection of miRNA-21. The detection limit was achieved as low as 0.2 fM with a wide dynamic response ranging from 10 fM to 100 nM, which is much more powerful or at least comparable to most of the reported studies. Furthermore, the electrochemical biosensor offered an excellent specificity, and even the single-base mutation against the perfectly matched target miRNA can be easily distinguished easily. Furthermore, the real biological samples were also desirably analyzed, indicating that the proposed strategy is an ideal platform for the fabrication of versatile DNA nanobiosensors.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Quadruplex G , MicroRNAs/análise , Nanoestruturas/química , Desenho de Fármacos , Limite de Detecção
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA