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1.
Nanotechnology ; 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33535190

RESUMO

Achieving a balanced strength-toughness in polymer composites is a challenge largely because of poor interfacial interaction between the fillers and matrix. Here, we report that terpolymer grafted multi-wall carbon nanotubes (Ter-CNT) imparted good dispersion of CNT in matrix and strong CNT-matrix interaction. With the addition of 2 vol% filler into polymethyl methacrylate (PMMA) matrix, the composite exhibited simultaneously a balanced strength-toughness property with flexural strength of 72.3 MPa, toughness of 10.1 MJ/m3, which increased by 40.1 % and 578 % compared with those of pure PMMA. In addition, the composite also shows a high static contact angle (110.3°), and high thermal conductivity (0.86 Wm/k), which endow the composite with good self-cleaning and thermal management capabilities. Thus, this preparation process shows guidance for the design of polymer composite with integrated high strength-toughness, thermal conductivity and good self-cleaning.

2.
Int J Mol Sci ; 22(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562315

RESUMO

Plasma membrane intrinsic proteins (PIPs) transport water, CO2 and small neutral solutes across the plasma membranes. In this study, we used the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 system (CRISPR/Cas9) to mutate PIP1;4 and PIP1;5 in a pip1;1,2,3 triple mutant to generate a pip1;1,2,3,4,5 (pip1s-) quintuple mutant. Compared to the wild-type (WT) plant, the pip1s- mutants had smaller sized rosette leaves and flowers, less rosette leaf number, more undeveloped siliques, shorter silique and less seeds. The pollen germination rate of the pip1s- mutant was significantly lower than that of the WT and the outer wall of the pip1s- mutant's pollen was deformed. The transcriptomic analysis showed significant alterations in the expression of many key genes and transcription factors (TFs) in the pip1s- mutant which involved in the development of leaf, flower and pollen, suggesting that the mutant of PIP1s not only directly affects hydraulics and carbon fixation, but also regulates the expression of related genes to affect plant growth and development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Flores/crescimento & desenvolvimento , Germinação , Proteínas de Membrana/metabolismo , Desenvolvimento Vegetal/genética , Pólen/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana/genética , Pólen/genética , Pólen/metabolismo
3.
Angle Orthod ; 90(3): 397-404, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33378431

RESUMO

OBJECTIVE: To evaluate three-dimensional (3D) accuracy and reliability of nonradiographic dentofacial images integrated with a two-step method. METHODS: 3D facial images, cone-beam computed tomography (CBCT) images and digital maxillary dental casts were obtained from 20 pre-orthodontic subjects. Digital dental casts were integrated into 3D facial images using a two-step method based on the anterior tooth area. 3D coordinate values of five dental landmarks were identified in both dentofacial images and CBCT images. The accuracy of the integration method was assessed with paired t-tests between dentofacial images and CBCT-based reference standards. Intraclass correlation coefficients (ICCs) were assessed for the reliability of dentofacial images and CBCT-based images. Analysis of variance and Kruskal-Wallis tests evaluated the accuracy of the method in different dimensions. RESULTS: There was no statistical difference between dentofacial images and CBCT reference standards in both translational and rotational dimensions (P > .05). Translational mean absolute errors for full dentitions were within 0.42 mm and ICCs were over 0.998 in x, y, and z directions. Rotational mean absolute errors for full dentitions were within 0.92° and ICCs over 0.734 in pitch, yaw, and roll orientations. Integration errors were significantly greater in the first molar, z-translation, and pitch rotation (P < .05). CONCLUSIONS: Integrating 3D dentofacial images with the two-step method is precise and acceptable for clinical diagnostics and scientific purposes. Errors were greater in the molar region, z-translation, and pitch rotation.


Assuntos
Imageamento Tridimensional , Maxila , Tomografia Computadorizada de Feixe Cônico , Arco Dental , Humanos , Maxila/diagnóstico por imagem , Reprodutibilidade dos Testes
4.
Front Chem ; 8: 819, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33102439

RESUMO

A total of six conjugated polymers, namely PDBT-Th, PDBT-Th:Th, PDBT-2Th, PDBT-Th:2Th, PDBT-2Th:Th, and PDBT-2Th:2Th, consisting of dibenzothiophene, thiophene, and bithiophene were electrochemically synthesized. Their electrochemical and electrochromic properties were investigated in relation to the conjugation chain lengths of the thiophene units in the conjugated backbones. Density functional theory (DFT) calculations showed that longer conjugation lengths resulted in decreased HOMO-LUMO gaps in the polymers. The optical band gaps (E g,opt) and electrochemical band gaps (E g,cv) were decreased from PDBT-Th to PDBT-Th:Th, however, PDBT-Th:2Th, PDBT-2Th, PDBT-2Th:Th and PDBT-2Th:2Th displayed the similar band gaps. The conjugation length increments significantly improved the electrochemical stability of the conjugated polymers and exhibited reversible color changes due to the formation of polarons and bipolarons. The results suggest that the conjugated polymers prepared herein are promising candidates for fabricating flexible organic electrochromic devices.

5.
Front Plant Sci ; 11: 574316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983222

RESUMO

Arabidopsis thaliana ENO2 (AtENO2) encodes two proteins AtENO2 (enolase) and AtMBP-1 (c-Myc binding protein 1-like). The loss of AtENO2 function causes the constitutive developmental defects which are correlated with reduced enolase activity, but not AtMBP-1 transcript abundance. However, the regulation mechanism of AtENO2 on the seed properties is still not clear. In this study, we found that the mutation of AtENO2 reduced the seed size and weight. The level of glucose in seed was significantly elevated but that of starch was decreased in AtENO2 mutants compared to WT plants. We also found that AtENO2 mutation reduced the content of cytokinin which resulted in smaller cotyledons. The RNA-seq data showed that there were 1892 differentially expressed genes and secondary metabolic pathways were significantly enriched. Instead of AtMBP-1, AtENO2 protein interacted with AtbZIP75 which may mediate the secondary metabolism. Therefore, ENO2 alters the size and weight of seeds which is not only regulated by the content of cytokinin and secondary metabolism, but may be affected by the interaction of ENO2 and bZIP57. These results are helpful to understand the novel function of AtENO2 which provide a foundation for further exploration of the key candidate genes for crop breeding.

6.
Physiol Plant ; 168(3): 660-674, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31343741

RESUMO

Arabidopsis thaliana ENO2 (AtENO2) plays an important role in plant growth and development. It encodes two proteins, a full-length AtENO2 and a truncated version, AtMBP-1, alternatively translated from the second start codon of the mRNA. The AtENO2 mutant (eno2- ) exhibited reduced leaf size, shortened siliques, a dwarf phenotype and higher sensitivity to abiotic stress. The objectives of this study were to analyze the regulatory network of the ENO2 gene in plant growth development and understand the function of AtENO2/AtMBP-1 to abiotic stresses. An eno2- /35S:AtENO2-GFP line and an eno2- /35S:AtMBP-1-GFP line of Arabidopsis were obtained. Results of sequencing by 454 GS FLX identified 578 upregulated and 720 downregulated differential expressed genes (DEGs) in a pairwise comparison (WT-VS-eno2- ). All the high-quality reads were annotated using the Gene Ontology (GO) terms. The DEGs with KEGG pathway annotations occurred in 110 pathways. The metabolic pathways and biosynthesis of secondary metabolites contained more DEGs. Moreover, the eno2- /35S:AtENO2-GFP line returned to the wild-type (WT) phenotype and was tolerant to drought and salt stresses. However, the eno2- /35S:AtMBP-1-GFP line was not able to recover the WT phenotype but it has a higher tolerance to drought and salt stresses. Results from this study demonstrate that AtENO2 is critical for the growth and development, and the AtMBP-1 coded by AtENO2 is important in tolerance of Arabidopsis to abiotic stresses.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Secas , Estresse Salino , Proteínas de Transporte , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas
7.
Neurosci Bull ; 35(6): 1035-1044, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31327148

RESUMO

ETS-1 is a transcription factor that is a member of the E26 transformation-specific (ETS) family. Galanin receptor 2 (GalR2), a subtype of receptors of the neuropeptide galanin, has been shown to have an antidepressant-like effect after activation in rodents. Our previous study has shown that overexpression of ETS-1 increases the expression of GalR2 in PC12 phaeochromocytoma cells. However, whether ETS-1 has an antidepressant-like effect is still unclear. In this study, we found that chronic mild stress (CMS) decreased the expression of both ETS-1 and GalR2 in the ventral hippocampus of rats. Meanwhile, we demonstrated that overexpression of ETS-1 increased the expression of GalR2 in primary hippocampal neurons. Importantly, we showed that overexpression of ETS-1 in the ventral hippocampus counteracted the depression-like behaviors of CMS rats. Furthermore, we found that overexpression of ETS-1 increased the level of downstream phosphorylated extracellular signal-regulated protein kinases 1 and 2 (p-ERK1/2) of GalR2 in the ventral hippocampus of CMS rats. Taken together, our findings suggest that ETS-1 has an antidepressant-like effect in rats, which might be mediated by increasing the level of GalR2 and its downstream p-ERK1/2 in the ventral hippocampus.


Assuntos
Depressão/metabolismo , Hipocampo/metabolismo , Proteína Proto-Oncogênica c-ets-1/metabolismo , Anedonia , Animais , Sistema de Sinalização das MAP Quinases , Masculino , Ratos , Ratos Sprague-Dawley , Receptor Tipo 2 de Galanina/metabolismo , Sacarose , Natação
8.
Angle Orthod ; 2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31958373

RESUMO

OBJECTIVE: To evaluate three-dimensional (3D) accuracy and reliability of nonradiographic dentofacial images integrated with a two-step method. METHODS: 3D facial images, cone-beam computed tomography (CBCT) images and digital maxillary dental casts were obtained from 20 pre-orthodontic subjects. Digital dental casts were integrated into 3D facial images using a two-step method based on the anterior tooth area. 3D coordinate values of five dental landmarks were identified in both dentofacial images and CBCT images. The accuracy of the integration method was assessed with paired t-tests between dentofacial images and CBCT-based reference standards. Intraclass correlation coefficients (ICCs) were assessed for the reliability of dentofacial images and CBCT-based images. Analysis of variance and Kruskal-Wallis tests evaluated the accuracy of the method in different dimensions. RESULTS: There was no statistical difference between dentofacial images and CBCT reference standards in both translational and rotational dimensions (P > .05). Translational mean absolute errors for full dentitions were within 0.42 mm and ICCs were over 0.998 in x, y, and z directions. Rotational mean absolute errors for full dentitions were within 0.92° and ICCs over 0.734 in pitch, yaw, and roll orientations. Integration errors were significantly greater in the first molar, z-translation, and pitch rotation (P < .05). CONCLUSIONS: Integrating 3D dentofacial images with the two-step method is precise and acceptable for clinical diagnostics and scientific purposes. Errors were greater in the molar region, z-translation, and pitch rotation.

9.
Int J Mol Sci ; 19(12)2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30518090

RESUMO

Alternatively translated from the ENO gene and expressed in an array of vertebrate and plant tissues, c-Myc binding protein 1 (MBP-1) participates in the regulation of growth in organisms, their development and their environmental responses. As a transcriptional repressor of multiple proto-oncogenes, vertebrate MBP-1 interacts with other cellular factors to attenuate the proliferation and metastasis of lung, breast, esophageal, gastric, bone, prostrate, colorectal, and cervical cancer cells. Due to its tumor-suppressive property, MBP-1 and its downstream targets have been investigated as potential prognostic markers and therapeutic targets for various cancers. In plants, MBP-1 plays an integral role in regulating growth and development, fertility and abiotic stress responses. A better understanding of the functions and regulatory factors of MBP-1 in plants may advance current efforts to maximize plant resistance against drought, high salinity, low temperature, and oxidative stress, thus optimizing land use and crop yields. In this review article, we summarize the research advances in biological functions and mechanistic pathways underlying MBP-1, describe our current knowledge of the ENO product and propose future research directions on vertebrate health as well as plant growth, development and abiotic stress responses.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Humanos , Neoplasias/metabolismo , Preparações Farmacêuticas , Desenvolvimento Vegetal , Vertebrados/metabolismo
10.
Food Chem ; 253: 5-12, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29502843

RESUMO

The antioxidant activity and genotoxicity of isogarcinol were assessed by several in vitro tests. Its IC50 values for DPPH and ABTS were 36.3 ±â€¯3.35 µM and 16.6 ±â€¯3.98 µM, respectively, which were all lower than those of VC and BHT. Isogarcinol had no cyctotoxic or promotional activities at 1-10 µM in the CCK-8 assay, and negligible genotoxic effects at 50-500 µM on HepG2 cells by the single-cell gel electrophoresis assay. Pre-incubation of the cells with 0.5-1.5 µM isogarcinol, before exposure to H2O2, significantly increased cell viability in a concentration-dependent manner. Isogarcinol also reduced intercellular reactive oxygen species accumulation, lactate dehydrogenase release and malondialdehyde levels, and increased superoxide dismutase activity and glutathione levels. Western-blot analysis revealed that it up-regulated pro-caspase-3 and reduced cleaved caspase-3 during H2O2-induced oxidative stress. All the above results indicate that isogarcinol promises to be useful as a natural antioxidant.


Assuntos
Antioxidantes/farmacologia , Antioxidantes/toxicidade , Mutagênicos/farmacologia , Mutagênicos/toxicidade , Terpenos/farmacologia , Terpenos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Concentração Inibidora 50 , Oxirredução , Estresse Oxidativo/efeitos dos fármacos
11.
Tumour Biol ; 39(7): 1010428317706915, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28714368

RESUMO

Bladder cancer is a neoplasm originated from bladder epithelial cells. The therapy for bladder cancer is so far not satisfactory. In this study, we examined the effects of Cordyceps militaris hot water extracts containing cordycepin on human bladder cells. Cordyceps militaris hot water extracts containing cordycepin was used to treat human T24 bladder carcinoma cells, and we found that Cordyceps militaris hot water extracts containing cordycepin decreased T24 cell survival in a dose-dependent manner, which was seemingly mediated by activation of A3 adenosine receptor and the subsequent inactivation of Akt pathways, resulting in increases in cleaved Caspase-3 and apoptosis. Overexpression of A3 adenosine receptor in T24 cells mimicked the effects of Cordyceps militaris hot water extracts, while A3 adenosine receptor depletion abolished the effects of Cordyceps militaris hot water extracts containing cordycepin. Together, these data suggest that Cordyceps militaris hot water extracts containing cordycepin may be a promising treatment for bladder cancer via A3 adenosine receptor activation.


Assuntos
Apoptose/efeitos dos fármacos , Desoxiadenosinas/administração & dosagem , Receptor A3 de Adenosina/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Caspase 3/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cordyceps/química , Desoxiadenosinas/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteína Oncogênica v-akt/genética , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
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