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1.
Polymers (Basel) ; 14(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36432936

RESUMO

Advanced organic vapor sensors that simultaneously have high sensitivity, fast response, and good reproducibility are required. Herein, flexible, robust, and conductive vapor-grown carbon fibers (VGCFs)-filled polydimethylsiloxane (PDMS) porous composites (VGCFs/PDMS sponge (CPS)) with multilevel pores and thin, rough, and hollows wall were prepared based on the sacrificial template method and a simple dip-spin-coating process. The optimized material showed outstanding mechanical elasticity and durability, good electrical conductivity and hydrophobicity, as well as excellent acid and alkali tolerance. Additionally, CPS exhibited good reproducible sensing behavior, with a high sensitivity of ~1.5 × 105 s-1 for both static and flowing organic vapor, which was not affected in cases such as 20% squeezing deformation or environment humidity distraction (20~60% RH). Interestingly, both the reproducibility and sensitivity of CPS were better than those of film-shaped VGCFs/PDMS (CP), which has a thickness of two hundred microns. Therefore, the contradiction between the reproducibility and high sensitivity was well-solved here. The above excellent performance could be ascribed to the unique porous structures and the rough, thin, hollow wall of CPS, providing various gas channels and large contact areas for organic vapor penetration and diffusion. This work paves a new way for developing advanced vapor sensors by optimizing and tailoring the pore structure.

2.
Zhen Ci Yan Jiu ; 45(4): 305-9, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32333536

RESUMO

OBJECTIVE: To observe the effect of moxibustion and acupoint catgut embedding (ACE) at "Tianshu"(ST25) "Dachangshu"(BL25) and "Shangjuxu"(ST37) on changes of body mass, stool property, histopathological conditions and expression levels of interleukin 6 (IL-6) in colonic mucosa of ulcerative colitis (UC) rats, so as to reveal its anti-inflammatory mechanisms underlying improvement of UC. METHODS: SD rats were randomized into normal, model, moxibustion, ACE and moxibustion+ACE groups (n=6 in each group). The UC model was established by enema of trinitro-benzene-sulfonic acid and ethanol. Moxibustion was applied to bilateral ST25, BL25 and ST37 for 10 min, once daily for 14 days, and ACE applied to the same 3 acupoints, once a week for two weeks. After the treatment, the rats' general conditions were observed, and the severity of UC was assessed by using disease activity index (DAI) score. Colonic mucosal pathological changes were observed under microscope after hematoxylin eosin (H.E.) stain, and the expression levels of IL-6 in the colonic mucosa tissue detected by using immunohistochemical stain and Western blot, respectively. RESULTS: After modeling, the DAI score, and expression level of colonic IL-6 protein detected by immunohistochemistry and Western blot were obviously increased in the model group relevant to the normal group (P<0.01). Following the intervention, the increase of DAI score and IL-6 expression were reversed in moxibustion, ACE and moxibustion+ACE groups (P<0.01, P<0.05). The therapeutic effects of moxibustion+ACE were considerably superior to those of simple ACE and simple moxibustion in down-regulating the levels of DAI score and IL-6 expression (P<0.01). H.E. staining showed severe defect of the colonic mucosal epithelium with infiltration of a large number of inflammatory cells in the model group, which was milder in moxibustion, ACE and moxibustion+ACE groups. CONCLUSION: Moxibustion combined with ACE is able to improve the inflammatory injury of colonic mucosa in UC rats, which may be related with its effect in suppressing the expression of colonic IL-6; and the efficacy of moxibustion+ACE is apparently superior to that of moxibustion and ACE alone.


Assuntos
Colite Ulcerativa , Moxibustão , Pontos de Acupuntura , Animais , Categute , Inflamação , Ratos , Ratos Sprague-Dawley
3.
Electrophoresis ; 41(3-4): 235-245, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31743462

RESUMO

A biogeographic estimate of a certain population can not only discern population substructure in the whole genome association study, but also provide informative clues for forensic investigations when obtained DNA genotypes do not find a match in the available forensic DNA database. In this study, 100 ancestry informative single nucleotide polymorphisms (AISNPs) were first presented to differentiate three continental ancestries (African, East Asian and European). Ultimately, forty-two AISNPs were chosen from the 100 AISNPs. Distinguishing power of the 100 and 42 AISNPs for differentiating continental populations was further evaluated with population cluster analyses. Results indicated both of AISNP sets could efficiently differentiate 11 training populations from the three continents. Further validation of 42 AISNPs in testing population set indicated these 42 AISNPs performed well for ancestry inferences of these testing individuals. Ancestry components of Uyghur group were assessed by comparing with different continental populations based on these 42 AISNPs. Results revealed that East Asian populations contributed more ancestry components to the studied Uyghur group than European populations. In conclusion, our study is expected to provide more AISNP markers and enrich extant reference database.


Assuntos
Etnicidade/genética , Genética Populacional/métodos , Polimorfismo de Nucleotídeo Único/genética , Grupos Raciais/genética , Genética Forense , Frequência do Gene/genética , Genótipo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
4.
Mol Biol Rep ; 47(2): 1079-1087, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31792748

RESUMO

Tibetans living in the Qing-Tibet plateau show unique genetic features since they are exposed to the high altitude environment. Accordingly, it is necessary for us to analyze genetic components of the Tibetan groups. Here, genetic structure and ancestry proportions of Tibet Tibetan and Qinghai Tibetan groups are dissected by using a previously published ancestral deletion/insertion polymorphisms (DIPs) panel. Genetic distributions of the analyzed DIPs in both Tibetan groups reveal that some DIPs show relatively balanced frequency distributions with the values ranging from 0.4 to 0.6, implying that these DIPs could be used as individual identification loci for forensic applications in both groups. Besides, the cumulative power of discrimination of the panel also reflects that the panel could serve as a valuable tool for forensic individual identifications in Tibet Tibetan and Qinghai Tibetan groups. Population genetic analyses including principal component analysis, DA genetic distances, phylogenetic tree, and genetic structure reveal that two studied Tibetan groups have closer genetic affiliations with East Asian populations. Genetic differentiation analyses of two Han populations, Xinjiang Uyghur and two Tibetan groups reveal that some DIP loci might be informative for differentiating Uyghurs from the other populations.


Assuntos
Povo Asiático/genética , Etnicidade/genética , Loci Gênicos , Genética Populacional , Mutação INDEL , Polimorfismo Genético , Alelos , China , Frequência do Gene , Geografia , Humanos , Desequilíbrio de Ligação , Tibet
5.
Sci Rep ; 9(1): 5659, 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30948734

RESUMO

A series of Ti/Li/Al ternary layered double hydroxides (TiLiAl-LDHs) with different Ti:Li:Al molar ratios were prepared by a coprecipitation method for photocatalytic CO2 reduction. It was demonstrated that the contents of anions between the layers of Ti/Li/Al-LDHs greatly determined the photocatalytic activity for CO2 reduction. With Ti:Li:Al molar ratios optimized to be 1:3:2, the largest contents of [Formula: see text]- anion and hydroxyl group were obtained for the Ti1Li3Al2-LDHs sample, which exhibited the highest photocatalytic activity for CO2 reduction, with CH4 production rate achieving 1.33 mmol h-1 g-1. Moreover, the theoretical calculations show that Ti1Li3Al2-LDHs is a p-type semiconductor with the narrowest band gap among all the obtained TiLiAl-LDHs. After calcined at high temperatures such as 700 °C, and the obtained TiLiAl-700 sample showed much increased photocatalytic activity for CO2 reduction, with CH4 production rate reaching about 1.59 mmol h-1 g-1. This calcination induced photocatalytic enhancement should be related to the cystal structure transformation from hydrotalcite to mixed oxides containing high reactive oxygen species for more efficient CO2 reduction.

6.
J Zhejiang Univ Sci B ; 20(3): 287-290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30829016

RESUMO

To further enrich the genetic data of the Chinese Xinjiang Mongolian group, the genetic distribution and forensic parameters of 19 autosomal short tandem repeats (STRs) were investigated. Altogether, 249 alleles were observed in these 19 STRs. The mean values of the polymorphism information content (PIC), match probability (MP), discrimination power (DP), and probability of exclusion (PE) for these 19 STRs were 0.7775, 0.0699, 0.9301, and 0.6085, respectively. Additionally, the cumulative DP and PE values obtained in the Mongolian group were 0.999 999 999 999 999 999 999 995 67 and 0.999 999 992 163, respectively. Furthermore, population genetic analysis of the Mongolian group and 20 published populations was conducted based on the population data of 15 overlapping STRs. Genetic distances indicated that the Mongolian group had closer genetic similarities with the Uyghur, Xibe, and other Chinese populations rather than the other continental populations. Multidimensional scaling analysis further revealed that the Mongolian group possessed similar genetic distributions as most Chinese populations. To sum it all up, these STRs could be used as an extremely efficient tool for forensic applications in the Xinjiang Mongolian group.


Assuntos
Povo Asiático/genética , Marcadores Genéticos , Repetições de Microssatélites , Alelos , China , Impressões Digitais de DNA , Bases de Dados Genéticas , Etnicidade/genética , Frequência do Gene , Genética Populacional , Genoma Humano , Humanos , Desequilíbrio de Ligação , Mongólia , Polimorfismo Genético , Análise de Componente Principal , Probabilidade , Software
7.
J Mater Chem B ; 6(37): 5986-5991, 2018 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32254718

RESUMO

A new class of biosensor molecules evoking fluorescent emission by rotation-restricted binding with bacteria was examined for its applicability in detecting live bacteria instantly. The fluorogens possessed multiple tetraphenylethene (TPE)-cored boronic acids to oligomerize through complexation with cis-diols on bacterial surfaces, resulting in aggregation-induced emission (AIE). The fluorogen having two boronic acid units discriminated between live and dead bacteria by showing AIE activity only with the latter. Live bacteria were instantly detected by consequent treatment with reagents of three and four di-boronates (which showed AIE activity with both live and dead bacteria). This phenomenon may lead to a practical method for live bacteria detection.

8.
PLoS One ; 11(9): e0158233, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27662186

RESUMO

During eating, the teeth usually endure the sharply temperature changes because of different foods. It is of importance to investigate the heat transfer and heat dissipation behavior of the dentino-enamel junction (DEJ) of human tooth since dentine and enamel have different thermophysical properties. The spatial and temporal temperature distributions on the enamel, dentine, and pulpal chamber of both the human tooth and its discontinuous boundaries, were measured using infrared thermography using a stepped temperature increase on the outer boundary of enamel crowns. The thermal diffusivities for enamel and dentine were deduced from the time dependent temperature change at the enamel and dentine layers. The thermal conductivities for enamel and dentine were calculated to be 0.81 Wm-1K-1 and 0.48 Wm-1K-1 respectively. The observed temperature discontinuities across the interfaces between enamel, dentine and pulp-chamber layers were due to the difference of thermal conductivities at interfaces rather than to the phase transformation. The temperature gradient distributes continuously across the enamel and dentine layers and their junction below a temperature of 42°C, whilst a negative thermal resistance is observed at interfaces above 42°C. These results suggest that the microstructure of the dentin-enamel junction (DEJ) junction play an important role in tooth heat transfer and protects the pulp from heat damage.

9.
Bioorg Med Chem Lett ; 23(11): 3314-9, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23601711

RESUMO

The small chemical compound 8-ethoxy-2-(4-fluorophenyl)-3-nitro-2H-chromene (S14161) was recently identified as an inhibitor of the phosphoinositide 3-kinase (PI3K). In the present study, we designed a novel synthesis of S14161 and prepared a series of its analogues via the oxa-Michael-Henry reaction in the presence of catalytic amounts of l-proline and triethylamine. Further structural simplification led to the identification of 6-bromo-8-ethoxy-3-nitro-2H-chromene (BENC-511) that exhibited potent antiproliferative activities against a panel of 12 tumor cell lines. Compared with S14161, BENC-511 was more potent in blocking the AKT phosphorylation and inducing cancer cell apoptosis. BENC-511 also displayed more potent effects on human umbilical vein epithelial cells (HUVEC) migration, suggesting its anti-angiogenesis activity.


Assuntos
Antineoplásicos/síntese química , Benzopiranos/química , Benzopiranos/síntese química , Inibidores de Fosfoinositídeo-3 Quinase , Antineoplásicos/química , Antineoplásicos/toxicidade , Benzopiranos/farmacologia , Sítios de Ligação , Catálise , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Células Endoteliais da Veia Umbilical Humana , Humanos , Simulação de Acoplamento Molecular , Neovascularização Fisiológica/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Piperazinas/química , Prolina/química , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-akt/metabolismo
10.
Curr Med Chem ; 20(15): 1997-2016, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23317165

RESUMO

Rheumatoid arthritis (RA) and other chronic inflammatory diseases are always the major therapeutic challenges. Recent research efforts provided new insights into the molecular basis of these diseases and new opportunities for developing improved anti-inflammatory drugs. The p38 mitogen-activated protein (MAP) kinase plays a central role in the regulation of the biosynthesis and release of several proinflammatory cytokines including tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1ß). Hence, inhibition of the p38 MAP kinase is regarded as a promising therapeutic strategy for controlling inflammatory diseases. A diverse range of p38α MAP kinase inhibitors have been developed as potential anti-inflammatory agents, and some of them have entered the phase II clinical trials. The imidazole derivatives are known as competitive inhibitors at the ATP binding site of the p38α MAP kinase. Modifications on the imidazole scaffold have led to a large amount of potent p38α MAP kinase inhibitors. This review will summarize the developments of small molecule p38α MAP kinase inhibitors based on the imidazole core scaffolds in recent 10 years. Variations at the N1, C2, C4 and C5 positions of imidazole were introduced, and the structure-activity relationships of these imidazole inhibitors were also discussed.


Assuntos
Anti-Inflamatórios/química , Artrite Reumatoide/tratamento farmacológico , Imidazóis/química , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Bibliotecas de Moléculas Pequenas/química , Animais , Anti-Inflamatórios/farmacologia , Artrite Reumatoide/enzimologia , Descoberta de Drogas , Humanos , Imidazóis/farmacologia , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade
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