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1.
Environ Res ; 214(Pt 2): 113805, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35810816

RESUMO

The incidence of thyroid cancer (TC) has increased considerably in the last few decades. Environmental factors, including plasticizers, are recognized as potential risks leading to thyroid cancer in humans. In this study, we used a transcriptome-metabolome-wide association study to find the unidentified carcinogenic mechanism of di-2-ethylhexyl phthalate (DEHP) in thyroid and biomarkers for non-invasive diagnosis. Rats were treated with different doses of DEHP (0, 0.3, 3, 30, 150 mg DEHP/kg bw/day) for 13 weeks. Then, the thyroids were processed for Ki67 staining and RNA-seq. Also, 17-h urine samples were collected for high-resolution metabolomics analysis. After a high dose of DEHP exposure, the terminal body weights and the thyroid and parathyroid glands weights were not altered. However, the liver weights and numbers of Ki67-positive cells were increased. Further, multivariate statistical analysis revealed that metabolic shifts were considerably altered above 30 mg DEHP/kg bw/day. In RNA-seq analysis, some cancer-related genes were altered, including 18 upregulated and 9 downregulated transcripts. These cancer transcripts and whole metabolome data were integrated to uncover thyroid cancer-related metabolic pathways, which revealed that cancer-related transcripts had a network structure linked to eicosanoids such as leukotriene D4 and prostaglandin. In brief, our study demonstrated that DEHP can induce thyroid hyperplasia through the eicosanoid-associated pathway, providing further insight into the mechanism of DEHP-associated thyroid cancer.


Assuntos
Dietilexilftalato , Neoplasias da Glândula Tireoide , Animais , Dietilexilftalato/toxicidade , Eicosanoides , Humanos , Antígeno Ki-67 , Metaboloma , Plastificantes , Ratos , Transcriptoma
2.
Chem Biodivers ; 19(1): e202100600, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34725898

RESUMO

Protein tyrosine phosphatases (PTPs) are essential modulators of signal transduction pathways and has been implicated in many human diseases such as cancer, diabetes, obesity, autoimmune disorders, and neurological diseases, indicating that PTPs are next-generation drug targets. Since PTPN1, PTPN2, and PTPN11 have been reported to be negative regulators of insulin action, the identification of PTP inhibitors may be an effective strategy to develop therapeutic agents for the treatment of type 2 diabetes. In this study, we observed for the first time that nepetin inhibits the catalytic activity of PTPN1, PTPN2, and PTPN11 in vitro, indicating that nepetin acts as a multi-targeting inhibitor of PTPN1, PTPN2, and PTPN11. Furthermore, treatment of mature 3T3-L1 adipocytes with 20 µM nepetin stimulates glucose uptake through AMPK activation. Taken together, our findings provide evidence that nepetin, a multi-targeting inhibitor of PTPN1, PTPN2, and PTPN11, could be a promising therapeutic candidate for the treatment of type 2 diabetes.


Assuntos
Inibidores Enzimáticos/química , Flavonas/química , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Biocatálise , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/patologia , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/uso terapêutico , Flavonas/metabolismo , Flavonas/uso terapêutico , Glucose/metabolismo , Humanos , Resistência à Insulina , Camundongos , Fosforilação/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 2/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Proteínas Tirosina Fosfatases/metabolismo
3.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563411

RESUMO

The emergence of the high correlation between type 2 diabetes and obesity with complicated conditions has led to the coinage of the term "diabesity". AMP-activated protein kinase (AMPK) activators and peroxisome proliferator-activated receptor (PPARγ) antagonists have shown therapeutic activity for diabesity, respectively. Hence, the discovery of compounds that activate AMPK as well as antagonize PPARγ may lead to the discovery of novel therapeutic agents for diabesity. In this study, the knockdown of PTPN6 activated AMPK and suppressed adipogenesis in 3T3-L1 cells. By screening a library of 1033 natural products against PTPN6, we found ethyl gallate to be the most selective inhibitor of PTPN6 (Ki = 3.4 µM). Subsequent assay identified ethyl gallate as the best PPARγ antagonist (IC50 = 5.4 µM) among the hit compounds inhibiting PTPN6. Ethyl gallate upregulated glucose uptake and downregulated adipogenesis in 3T3-L1 cells as anticipated. These results strongly suggest that ethyl gallate, which targets both PTPN6 and PPARγ, is a potent therapeutic candidate to combat diabesity.


Assuntos
Diabetes Mellitus Tipo 2 , Ácido Gálico , PPAR gama , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/metabolismo , Adipogenia , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Ácido Gálico/análogos & derivados , Ácido Gálico/farmacologia , Camundongos , Obesidade/tratamento farmacológico , Obesidade/metabolismo , PPAR gama/efeitos dos fármacos , PPAR gama/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo
4.
Int J Mol Sci ; 23(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35457082

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative motor disorder without an available therapeutic to halt the formation of Lewy bodies for preventing dopaminergic neuronal loss in the nigrostriatal pathway. Since oxidative-stress-mediated damage has been commonly reported as one of the main pathological mechanisms in PD, we assessed the efficacy of a novel NOX inhibitor from AptaBio Therapeutics (C-6) in dopaminergic cells and PD mouse models. The compound reduced the cytotoxicity and enhanced the cell viability at various concentrations against MPP+ and α-synuclein preformed fibrils (PFFs). Further, the levels of ROS and protein aggregation were significantly reduced at the optimal concentration (1 µM). Using two different mouse models, we gavaged C-6 at two different doses to the PD sign-displaying transgenic mice for 2 weeks and stereotaxically PFF-injected mice for 5 weeks. Our results demonstrated that both C-6-treated mouse models showed alleviated motor deficits in pole test, hindlimb clasping, crossbeam, rotarod, grooming, and nesting analyses. We also confirmed that the compound treatment reduced the levels of protein aggregation, along with phosphorylated-α-synuclein, in the striatum and ventral midbrain and further dopaminergic neuronal loss. Taken together, our results strongly suggest that NOX inhibition can be a potential therapeutic target for PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Camundongos , Camundongos Transgênicos , Degeneração Neural/patologia , Doença de Parkinson/metabolismo , Agregados Proteicos , alfa-Sinucleína/metabolismo
5.
Metabolomics ; 16(1): 9, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31872321

RESUMO

INTRODUCTION: Despite the advances in diagnosis and treatment, malaria has still not been eradicated. Metabolic interactions between the host and Plasmodium may present novel targets for malaria control, but such interactions are yet to be deciphered. An exploration of metabolic interactions between humans and two Plasmodium species by high-resolution metabolomics may provide fundamental insights that can aid the development of a new strategy for the control of malaria. OBJECTIVES: This study aimed at exploring the metabolic changes in the sera of patients infected with Plasmodium falciparum and Plasmodium vivax. METHODS: Uni- and multivariate metabolomic analyses were performed on the sera of four groups of patients, namely normal control (N, n = 100), P. falciparum-infected patients (PF, n = 21), P. vivax-infected patients (PV, n = 74), and non-malarial pyretic patients (Pyr, n = 25). RESULTS: Univariate and multivariate analyses of N, PF, and PV groups showed differential metabolic phenotypes and subsequent comparisons in pairs revealed significant features. Pathway enrichment test with significant features showed the affected pathways, namely glycolysis/gluconeogenesis for PF and retinol metabolism for PV. The metabolites belonging to the affected pathways included significantly low 2,3-diphosphoglycerate and glyceraldehyde-3-phosphate in the sera of PF. The sera of PV had significantly low levels of retinol but high levels of retinoic acid. CONCLUSION: Our study reveals metabolic alterations induced by Plasmodium spp. in human serum and would serve as a milestone in the development of novel anti-malarial strategies.


Assuntos
Biomarcadores/sangue , Malária/patologia , Metabolômica , Plasmodium falciparum/fisiologia , Plasmodium vivax/fisiologia , 2,3-Difosfoglicerato/sangue , Adulto , Idoso , Estudos de Casos e Controles , Análise por Conglomerados , Análise Discriminante , Feminino , Gliceraldeído 3-Fosfato/sangue , Humanos , Malária/metabolismo , Malária/parasitologia , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Tretinoína/sangue , Vitamina A/sangue
6.
Nucleic Acids Res ; 43(W1): W413-8, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25904629

RESUMO

Molecular cavities, which include voids and channels, are critical for molecular function. We present a webserver, BetaCavityWeb, which computes these cavities for a given molecular structure and a given spherical probe, and reports their geometrical properties: volume, boundary area, buried area, etc. The server's algorithms are based on the Voronoi diagram of atoms and its derivative construct: the beta-complex. The correctness of the computed result and computational efficiency are both mathematically guaranteed. BetaCavityWeb is freely accessible at the Voronoi Diagram Research Center (VDRC) (http://voronoi.hanyang.ac.kr/betacavityweb).


Assuntos
Conformação Molecular , Software , Algoritmos , Internet , Modelos Moleculares , Conformação Proteica
7.
Immunol Invest ; 44(3): 309-20, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25831081

RESUMO

Fascin is a well-known cytoskeletal regulatory protein that, as a substrate of protein kinase C (PKC), is involved in PKC-mediated translational regulation of TNF-α in macrophages stimulated with lipopolysaccharide (LPS). The regulatory effects of fascin targeted the 3'-untraslated region (UTR) of the TNF-α mRNA, and suppression of PKC activity or fascin expression resulted in specific blockage of the LPS-induced translational activation of the mRNA. In an effort to identify the molecular mechanism of this fascin-mediated translational regulation, the expression levels of micro-RNA (miRNA) after stimulation of the toll-like receptor 4 (TLR4) signaling pathways were analyzed in cells with down-regulation of fascin. The LPS-induced translation of TNF-α is known to be regulated by miR-155 and miR-125b, which have positive and negative effects, respectively. Interestingly, suppression of fascin expression reversed LPS-induced down-regulation of miR-125b and abolished the LPS-induced increase in miR-155. Furthermore, introduction of miR-155 precursor, blocking of miR-125b activity, or introduction of a mutation into the miR-125b binding site of the TNF-α 3'-UTR restored translational activation in cells with suppressed fascin expression. These data indicate that fascin regulates translation through miR-155 and miR-125b, which target 3' UTR in TNF-α mRNA.


Assuntos
Proteínas de Transporte/metabolismo , Macrófagos/fisiologia , MicroRNAs/metabolismo , Proteínas dos Microfilamentos/metabolismo , Fator de Necrose Tumoral alfa/genética , Regiões 3' não Traduzidas/genética , Sítios de Ligação/genética , Proteínas de Transporte/genética , Regulação da Expressão Gênica/genética , Células HEK293 , Humanos , Lipopolissacarídeos/imunologia , MicroRNAs/genética , Proteínas dos Microfilamentos/genética , Mutação/genética , Biossíntese de Proteínas/genética , Proteína Quinase C/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Transdução de Sinais/genética , Receptor 4 Toll-Like/metabolismo
8.
Proteins ; 82(9): 1829-49, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24677176

RESUMO

Molecular external structure is important for molecular function, with voids on the surface and interior being one of the most important features. Hence, recognition of molecular voids and accurate computation of their geometrical properties, such as volume, area and topology, are crucial, yet most popular algorithms are based on the crude use of sampling points and thus are approximations even with a significant amount of computation. In this article, we propose an analytic approach to the problem using the Voronoi diagram of atoms and the beta-complex. The correctness and efficiency of the proposed algorithm is mathematically proved and experimentally verified. The benchmark test clearly shows the superiority of BetaVoid to two popular programs: VOIDOO and CASTp. The proposed algorithm is implemented in the BetaVoid program which is freely available at the Voronoi Diagram Research Center (http://voronoi.hanyang.ac.kr).


Assuntos
Modelos Moleculares , Conformação Molecular , Dobramento de Proteína , Proteínas/ultraestrutura , Algoritmos , Simulação por Computador , Estrutura Terciária de Proteína
9.
Acta Crystallogr D Biol Crystallogr ; 70(Pt 2): 421-35, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24531476

RESUMO

Dual-specificity protein phosphatases (DUSPs), which dephosphorylate both phosphoserine/threonine and phosphotyrosine, play vital roles in immune activation, brain function and cell-growth signalling. A family-wide structural library of human DUSPs was constructed based on experimental structure determination supplemented with homology modelling. The catalytic domain of each individual DUSP has characteristic features in the active site and in surface-charge distribution, indicating substrate-interaction specificity. The active-site loop-to-strand switch occurs in a subtype-specific manner, indicating that the switch process is necessary for characteristic substrate interactions in the corresponding DUSPs. A comprehensive analysis of the activity-inhibition profile and active-site geometry of DUSPs revealed a novel role of the active-pocket structure in the substrate specificity of DUSPs. A structure-based analysis of redox responses indicated that the additional cysteine residues are important for the protection of enzyme activity. The family-wide structures of DUSPs form a basis for the understanding of phosphorylation-mediated signal transduction and the development of therapeutics.


Assuntos
Fosfatases de Especificidade Dupla/química , Fosfatases de Especificidade Dupla/classificação , Inibidores Enzimáticos/química , Filogenia , Domínio Catalítico , Cristalografia por Raios X , Cisteína/química , Fosfatases de Especificidade Dupla/antagonistas & inibidores , Fosfatases de Especificidade Dupla/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Hidrólise , Modelos Moleculares , Oxirredução , Fosfosserina/química , Fosfotreonina/química , Fosfotirosina/química , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/classificação , Proteínas Recombinantes/genética , Transdução de Sinais , Homologia Estrutural de Proteína , Especificidade por Substrato
10.
Proteins ; 81(8): 1420-33, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23568277

RESUMO

We present a new four-body knowledge-based potential for recognizing the native state of proteins from their misfolded states. This potential was extracted from a large set of protein structures determined by X-ray crystallography using BetaMol, a software based on the recent theory of the beta-complex (ß-complex) and quasi-triangulation of the Voronoi diagram of spheres. This geometric construct reflects the size difference among atoms in their full Euclidean metric; property not accounted for in a typical 3D Delaunay triangulation. The ability of this potential to identify the native conformation over a large set of decoys was evaluated. Experiments show that this potential outperforms a potential constructed with a classical Delaunay triangulation in decoy discrimination tests. The addition of a statistical hydrogen bond potential to our four-body potential allows a significant improvement in the decoy discrimination, in such a way that we are able to predict successfully the native structure in 90% of cases.


Assuntos
Dobramento de Proteína , Proteínas/química , Algoritmos , Bases de Dados de Proteínas , Ligação de Hidrogênio , Modelos Moleculares , Conformação Proteica
11.
J Comput Chem ; 34(30): 2647-56, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24108416

RESUMO

In this article, an enhanced version of GalaxyDock protein-ligand docking program is introduced. GalaxyDock performs conformational space annealing (CSA) global optimization to find the optimal binding pose of a ligand both in the rigid-receptor mode and the flexible-receptor mode. Binding pose prediction has been improved compared to the earlier version by the efficient generation of high-quality initial conformations for CSA using a predocking method based on a beta-complex derived from the Voronoi diagram of receptor atoms. Binding affinity prediction has also been enhanced by using the optimal combination of energy components, while taking into consideration the energy of the unbound ligand state. The new version has been tested in terms of binding mode prediction, binding affinity prediction, and virtual screening on several benchmark sets, showing improved performance over the previous version and AutoDock, on which the GalaxyDock energy function is based. GalaxyDock2 also performs better than or comparable to other state-of-the-art docking programs. GalaxyDock2 is freely available at http://galaxy.seoklab.org/softwares/galaxydock.html.


Assuntos
Simulação de Acoplamento Molecular , Proteínas/química , Ligantes , Modelos Moleculares
12.
J Immunol ; 187(12): 6327-34, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22102721

RESUMO

Fascin, as a substrate of protein kinase C (PKC), is a well-known cytoskeletal regulatory protein required for cell migration, invasion, and adhesion in normal and cancer cells. In an effort to identify the role of fascin in PKC-mediated cellular signaling, its expression was suppressed by stable transfection of specific short hairpin RNAs (shRNAs) in mouse monocytic leukemia RAW264.7 cells. Suppression of fascin expression resulted in impaired cellular migration and invasion through extracellular matrix proteins. Unexpectedly, the specific shRNA transfectants exhibited a marked reduction in LPS-induced expression of TNF-α and IL-6 by blocking the translation of their mRNAs. Transient transfection assay using a luciferase expression construct containing the 3' untranslated region of TNF-α or IL-6 mRNA revealed a significant reduction in both LPS- and PMA- (the direct activator of PKC) induced reporter activity in cells transfected with fascin-specific shRNA, indicating that fascin-mediated translational regulation targeted 3' untranslated region. Furthermore, LPS-induced translational activation of reporter expression was blocked by a pharmacological inhibitor of PKC, and the dominant-negative form of PKCα attenuated LPS-induced translational activation. The same type of regulation was also observed in the human monocytic leukemia cell line THP-1 and in mouse peritoneal macrophages. These data demonstrate the involvement of fascin in the PKC-mediated translational regulation of TNF-α and IL-6 expression during the LPS response.


Assuntos
Proteínas de Transporte/fisiologia , Interleucina-6/genética , Lipopolissacarídeos/farmacologia , Proteínas dos Microfilamentos/fisiologia , Biossíntese de Proteínas/imunologia , Proteína Quinase C/fisiologia , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/genética , Animais , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/biossíntese , Linhagem Celular , Linhagem Celular Tumoral , Inibição de Migração Celular/genética , Inibição de Migração Celular/imunologia , Proteínas da Matriz Extracelular/antagonistas & inibidores , Proteínas da Matriz Extracelular/fisiologia , Humanos , Interleucina-6/antagonistas & inibidores , Interleucina-6/biossíntese , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos ICR , Proteínas dos Microfilamentos/antagonistas & inibidores , Proteínas dos Microfilamentos/biossíntese , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
13.
J Nanosci Nanotechnol ; 13(10): 7173-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24245221

RESUMO

The formation of nanometer-scale (ns)-Si dots and clusters on p-GaN layers has been studied by controlling the early stage of growth during plasma-enhanced chemical vapor deposition (PECVD) at room temperature. We found that ns-Si dots and clusters formed on the p-GaN surface, indicating that growth was the Volmer-Weber mode. The deposition parameters such as radio frequency (RF) power and processing time mainly influenced the size of the ns-Si dots (40 nm-160 nm) and the density of the ns-Si dot clusters.

14.
J Nanosci Nanotechnol ; 13(8): 5715-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882823

RESUMO

The electrical properties of Ni-based ohmic contacts to N-face p-type GaN were investigated. The specific contact resistance of N-face p-GaN exhibits a linear decrease from 1.01 omega cm2 to 9.05 x 10(-3) omega cm2 for the as-deposited and the annealed Ni/Au contacts, respectively, with increasing annealing temperature. However, the specific contact resistance could be decreased down to 1.03 x 10(-4) omega cm2 by means of surface treatment using an alcohol-based (NH4)2S solution. The depth profile data measured from the intensity of O1s peak in the X-ray photoemission spectra showed that the alcohol-based (NH4)2S treatment was effective in removing the surface oxide layer of GaN.

15.
J Hazard Mater ; 446: 130659, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36587596

RESUMO

This study aimed to investigate the relationship among chronic exposure to a low concentration of organochlorine pesticides (OCPs), high-fat diet (HFD)-induced obesity, and caloric restriction in type 2 diabetes (T2D). Thus, female zebrafish were divided into four groups and treated for 12 weeks as follows: (i) negative control, (ii) HFD (obesity) control, (iii) obesity + a mixture of OCPs (OP), and (iv) obesity + a mixture of OCPs + caloric restriction (OPR). We then assessed T2D-related effects via hematological analysis, histopathology, mitochondrial evaluation, and multiomics analyses. The OP group showed a significant increase in glucose levels, whereas the OPR group maintained glucose at nonsignificant levels. Multiomics analyses revealed that the exacerbated metabolic effects in the OP group were associated with molecular alterations in oxidative stress, inflammation, nucleotide metabolism, and glucose/lipid homeostasis. These alterations were histologically verified by the increased numbers of hypertrophic adipocytes and inflammatory cells observed. Caloric restriction activated pathways related to antioxidant response, mitochondrial fatty acid oxidation, and energy metabolism in zebrafish, leading to preserved glucose homeostasis. In conclusion, this study identified molecular mechanisms underlying the synergistic effect of concurrent exposure to a mixture of OCPs and HFD as well as shed light on the beneficial effect of regular caloric restriction in T2D development.


Assuntos
Diabetes Mellitus Tipo 2 , Praguicidas , Animais , Feminino , Restrição Calórica , Dieta Hiperlipídica/efeitos adversos , Peixe-Zebra , Obesidade/metabolismo , Glucose , Praguicidas/toxicidade
16.
Cancer Invest ; 30(5): 364-71, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22571339

RESUMO

Increasing evidence supports that inflammation is closely associated with the development of cancer. In an effort to develop synthetic peptides that can suppress the inflammatory activation of cancer cells, decapeptides representing immunoreceptor tyrosine-based inhibitory motif (ITIM)-like sequences of immune receptor expressed on myeloid cells-1 (IREM-1) were tested for their anti-inflammatory effects in cancer cell lines. One (named TAT-YADL) out of the five synthetic peptides tested exhibited inhibitory effects on the expression of inflammatory mediators as well as invasion and migration. The inhibitory activities of the synthetic peptides required activation of SH2-containing protein tyrosine phosphatase-1 (SHP-1) and phosphoinositide 3-kinase (PI3K).


Assuntos
Mediadores da Inflamação/antagonistas & inibidores , Peptídeos/farmacologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , DNA/metabolismo , Humanos , NF-kappa B/metabolismo , Invasividade Neoplásica , Estrutura Terciária de Proteína , Fator de Necrose Tumoral alfa/antagonistas & inibidores
17.
Nanotechnology ; 23(23): 235303, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22595765

RESUMO

We report on nanoimprinting of polymer thin films at 30 nm scale resolution using two types of ultraviolet (UV)-curable, flexible polymer molds: perfluoropolyether (PFPE) and polyurethane acrylate (PUA). It was found that the quality of nanopatterning at the 30 nm scale is largely determined by the combined effects of surface tension and the coefficient of thermal expansion of the polymer mold. In particular, the polar component of surface tension may play a critical role in clean release of the mold, as evidenced by much reduced delamination or broken structures for the less polarized PFPE mold when patterning a relatively hydrophilic PMMA film. In contrast, such problems were not notably observed with a relatively hydrophobic PS film for both polymer molds. In addition, the demolding characteristic was also influenced by the coefficient of thermal expansion so that no delamination or uniformity problems were observed when patterning a UV-curable polymer film at room temperature. These results suggest that a proper polymeric mold material needs to be chosen for patterning polymer films under different surface properties and processing conditions, providing insights into how a clean demolding characteristic can be obtained at 30 nm scale nanopatterning.


Assuntos
Cristalização/métodos , Impressão Molecular/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Polímeros/química , Módulo de Elasticidade , Temperatura Alta , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície , Tensão Superficial , Condutividade Térmica
18.
J Air Waste Manag Assoc ; 62(2): 235-41, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22442939

RESUMO

In this study, the physicochemical properties of the char of Indonesian SM coal following heat treatment at various temperatures were evaluated using X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and morphological and specific surface area analysis. Based on these analyses, heat treatment of coal was determined to be the most effective in increasing the coal rank. In the XPS analysis, the C-O and C-O-C groups and quaternary-N species were found to be of a lower grade coal when the pretreatment temperature decreased, meanwhile the C-C group and pyridinic species increased. In the FT-IR analysis, the collapse of the C-O and C-O-C group was observed due to the collapse of the ether group. In SEM and Brunauer-Emmett-Teller (BET) analysis, a decrease in the ether group was shown to be accompanied with the formation of micropores.


Assuntos
Carvão Mineral/análise , Temperatura Alta , Espectroscopia Fotoeletrônica
19.
Artigo em Inglês | MEDLINE | ID: mdl-35206537

RESUMO

Sepsis is a life-threatening condition with a high mortality rate. Early prediction and treatment are the most effective strategies for increasing survival rates. This paper proposes a neural architecture search (NAS) model to predict the onset of sepsis with a low computational cost and high search performance by applying a genetic algorithm (GA). The proposed model shares the weights of all possible connection nodes internally within the neural network. Externally, the search cost is reduced through the weight-sharing effect between the genotypes of the GA. A predictive analysis was performed using the Medical Information Mart for Intensive Care III (MIMIC-III), a medical time-series dataset, with the primary objective of predicting sepsis onset 3 h before occurrence. In addition, experiments were conducted under various prediction times (0-12 h) for comparison. The proposed model exhibited an area under the receiver operating characteristic curve (AUROC) score of 0.94 (95% CI: 0.92-0.96) for 3 h, which is 0.31-0.26 higher than the scores obtained using the Sequential Organ Failure Assessment (SOFA), quick SOFA (qSOFA), and Simplified Acute Physiology Score (SAPS) II scoring systems. Furthermore, the proposed model exhibited a 12% improvement in the AUROC value over a simple model based on the long short-term memory neural network. Additionally, it is not only optimally searchable for sepsis onset prediction, but also outperforms conventional models that use similar predictive purposes and datasets. Notably, it is sufficiently robust to shape changes in the input data and has less structural dependence.


Assuntos
Unidades de Terapia Intensiva , Sepse , Algoritmos , Cuidados Críticos , Mortalidade Hospitalar , Humanos , Curva ROC , Estudos Retrospectivos , Sepse/diagnóstico
20.
J Nanosci Nanotechnol ; 11(8): 7495-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22103228

RESUMO

380 nm ultraviolet (UV) light emitting diodes (LEDs) were grown on patterned n-type GaN substrate (PNS) with silicon dioxide (SiO2) nano pattern to improve the light output efficiency. Wet etched self assembled indium tin oxide (ITO) nano clusters serves as dry etching mask for converting the SiO2 layer grown on n-GaN template into SiO2 nano patterns by inductively coupled plasma etching. Three different diameter of ITO such as 200, 250 and 300 nm were used for SiO2 nano pattern fabrication. PNS is obtained by n-GaN regrowth on SiO2 nano patterns and UV LEDs were grown on PNS template by MOCVD. Enhanced light output intensity was observed by employing SiO2 nano patterns on n-GaN. Among different PNS UV LEDs, LED grown on PNS with 300 nm ITO diameter showed enhancement in light output intensity by 2.1 times compared to the reference LED without PNS.

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