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1.
Phys Chem Chem Phys ; 26(10): 8426-8435, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38407835

RESUMEN

In order to develop candidate materials for more metal ion battery anodes, a three-dimensional (3D) porous structure 3D-PGY was designed based on graphyne, and a sandwich structure graphene/PGY/graphene (G/PGY/G) was constructed by adjusting the distance between two layers of graphene with 3D-PGY as the middle layer. Systematic calculations have shown that 3D-PGY is thermally and mechanically stable even at temperatures up to 1000 K. Li can migrate in multiple diffusion directions in two structures because of its smaller radius while Na and K ions can only migrate through the larger pores. The energy barriers of Li, Na and K ions in 3D-PGY are 0.18, 0.43 and 0.27 eV respectively. After forming the sandwich structure with graphene, the minimum energy barriers of Li, Na and K ions are decreased to 0.12, 0.37 and 0.24 eV, respectively. As the anode for Li, Na, and K ion batteries, the theoretical specific capacities of 3D-PGY are about 558 mA h g-1, and the average open circuit voltages of 3D-PGY and G/PGY/G are about 0.48/0.52/0.29 and 1.08/1.04/1.39 V, respectively. Finally, using ab initio molecular dynamics simulations, the diffusion coefficients for 3D-PGY at different temperatures, as well as for G/PGY/G at 400 K were obtained. The Li, Na and K ions in both structures can diffuse rapidly and have good rate capabilities. These excellent performances show that the graphyne-based 3D porous structure and its sandwich-type graphene structure are very promising for the development of new battery materials.

2.
J Sci Food Agric ; 104(2): 1178-1189, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37743545

RESUMEN

BACKGROUND: Riboflavin, a vital water-soluble vitamin with antioxidative activity, plays a critical role in maintaining overall bodily health and defense responses. However, its impact on fragrant rice yield and aroma remains unexplored. RESULTS: In a 2022 pot experiment with Meixiangzhan and Yuxiangyouzhan fragrant rice cultivars, we applied riboflavin foliar treatments at concentrations of 0 (CK), 10 (R10), 20 (R20), and 40 (R40) mg L-1 during the initial heading stage. Riboflavin increased rice yield, 2-acetyl-1-pyrroline (2-AP) content, and antioxidative properties. It boosted 2-AP level by 13.1-50.1% for Meixiangzhan and 22.3-35.3% for Yuxiangyouzhan, with the highest levels in R20 and R10 treatments. This increase is significantly correlated with elevated levels of proline, pyrroline-5-carboxylic acid, pyrroline, and methylglyoxal, as well as heightened enzyme activities, including those of proline dehydrogenase, ornithine aminotransferase, and pyrroline-5-carboxylic acid synthetase (P5CS). The R20 treatment resulted in the highest yield due to an improved seed-setting rate. Importantly, a positive correlation emerged between 2-AP content and yield, both significantly linked to superoxide dismutase, proline, hydrogen peroxide, P5CS, catalase, and pyrroline. CONCLUSION: Riboflavin maintained enzyme activities, regulated substance synthesis pathways, and increased 2-AP and yield, especially in the R20 treatment. These insights advance fragrant rice production theory by uncovering riboflavin's role in the development of fragrant rice. © 2023 Society of Chemical Industry.


Asunto(s)
Antioxidantes , Oryza , Antioxidantes/farmacología , Antioxidantes/metabolismo , Oryza/química , Odorantes/análisis , Grano Comestible/metabolismo , Pirroles/farmacología , Pirroles/metabolismo , Riboflavina , Prolina/metabolismo , Ácidos Carboxílicos/metabolismo
3.
Angew Chem Int Ed Engl ; : e202407928, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39022842

RESUMEN

Although highly appealing for rapid access of molecular complexity, multi-functionalization of alkenes that allows incorporation of more than two functional groups remains a prominent challenge. Herein, we report a novel strategy that merges dipolar cycloaddition with photoredox promoted radical ring-opening remote C(sp3)-H functionalization, thus enabling a smooth 1,2,5-trifunctionalization of unactivated alkenes. A highly regioselective [3+2] cycloaddition anchors a reaction trigger onto alkene substrates. The subsequent halogen atom transfer (XAT) selectively initiates ring-opening process, which is followed by a series of 1,5-hydrogen atom transfer (1,5-HAT) and intermolecular fluorine atom transfer (FAT) events. With this method, site-selective introduction of three different functional groups is accomplished and a broad spectrum of valuable ß-hydroxyl-ε-fluoro-nitrile products are synthesized from readily available terminal alkenes.

4.
Theor Appl Genet ; 136(4): 80, 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36952057

RESUMEN

KEY MESSAGE: A novel quantitative trait locus for early flowering in spring oilseed rape, BnaC08cqDTF, was mapped to an 86-kb region on chromosome C08, and its causal gene, CRY2, was uncovered. Days to flowering is a very important agronomic and adaptive trait of Brassica napus oilseed rape (AACC, 2n = 38). We previously identified BnaC08cqDTF as a novel candidate quantitative trait locus (QTL) for early flowering in spring oilseed rape. Here, we present fine mapping of the locus and a study of its causal gene. Initial mapping was performed by QTL sequencing of DNA pools of BC3F2 plants with extreme flowering times derived from crosses between the spring-type cv. No. 4512 (early flowering) and cv. No. 5246 (late flowering), along with fine mapping by target sequencing of the BC3F2 and BC4F2 populations. Fine mapping narrowed down BnaC08cqDTF to an 86-kb region on chromosome C08. The region harbored fifteen genes. After comparative analyses of the DNA sequences for mutation between A and C syntenic regions and detected by RNA-seq and qRT-PCR between the two parents, we found that BnaC08G0010400ZS harbors an A/G nonsynonymous mutation in exon 3. This single nucleotide polymorphism (SNP) haplotype was also correlated with early flowering in a 256 accession panel. BnaC08G0010400ZS is a homolog of the AT1G04400 gene (CRY2) in Arabidopsis. The analyses of transgenic Arabidopsis verified that BnaC08G0010400ZS is responsible for early flowering. Our results contribute to a better understanding of the genetic control mechanism of early flowering in spring Brassica napus and will promote the breeding for early mature varieties.


Asunto(s)
Arabidopsis , Brassica napus , Sitios de Carácter Cuantitativo , Brassica napus/genética , RNA-Seq , Arabidopsis/genética , Fitomejoramiento
5.
Chemphyschem ; 24(17): e202300290, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37306634

RESUMEN

The development of lithium-ion batteries with simplified assembling steps and fast charge capability is crucial for current battery applications. In this study, we propose a simple in-situ strategy for the construction of high-dispersive cobalt oxide (CoO) nanoneedle arrays, which grow vertically on a copper foam substrate. It is demonstrated that this nanoneedle CoO electrodes provide abundant electrochemical surface area. The resulting CoO arrays directly act as binder-free anodes in lithium-ion batteries with the copper foam functioning as the current collector. The highly-dispersed feature of the nanoneedle arrays enhances the effectiveness of active materials, leading to outstanding rate capability and superior long-term cycling stability. These impressive electrochemical properties are attributed to the highly-dispersed self-standing nanoarrays, the advantages of binder-free constituent, and the high exposed surface area of the copper foam substrate compared to copper foil, which enrich active surface area and facilitate charge transfer. The proposed approach to prepare binder-free lithium-ion battery anodes streamlines the electrode fabrication steps and holds significant promise for the future development of the battery industry.

6.
Dev Psychopathol ; : 1-15, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38111966

RESUMEN

Peer victimization and depressive symptoms are highly relevant risks during adolescence. Understanding the dynamic patterns of interactions between peer victimization and depressive symptoms as well as gender differences in these variables can improve intervention strategies for adolescents navigating this critical transition period. In the present study, a large sample of Chinese adolescents reported peer victimization and depressive symptoms in four survey waves at six-month intervals. A total of 2534 adolescents (51.9% boys, M = 12.98 ± 0.60 years) were included in the latent change score (LCS) analysis. The results supported the reciprocal effects model obtained in the full sample. Changes in peer victimization were influenced by prior changes in depressive symptoms over time, and changes in depressive symptoms were influenced by prior levels of peer victimization. There were also gender differences, with boys exhibiting depressive symptom-driven effects on peer victimization, while girls exhibiting peer victimization-induced depressive symptoms. The dynamic relationships between peer victimization and depressive symptoms that promote and constrain each other in adolescents are elucidated in this study. Differentiating effects on boys and girls is crucial for enhancing the effectiveness of practical interventions.

7.
Theor Appl Genet ; 135(4): 1319-1330, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35059781

RESUMEN

KEY MESSAGE: A major QTL, qBWA12, was fine mapped to a 216.68 kb physical region, and A12.4097252 was identified as a useful KASP marker for breeding peanut varieties resistant to bacterial wilt. Bacterial wilt, caused by Ralstonia solanacearum, is a major disease detrimental to peanut production in China. Breeding disease-resistant peanut varieties is the most economical and effective way to prevent the disease and yield loss. Fine mapping the QTLs for bacterial wilt resistance is critical for the marker-assisted breeding of disease-resistant varieties. A recombinant inbred population comprising 521 lines was used to construct a high-density genetic linkage map and to identify QTLs for bacterial wilt resistance following restriction-site-associated DNA sequencing. The genetic map, which included 5120 SNP markers, covered a length of 3179 cM with an average marker distance of 0.6 cM. Four QTLs for bacterial wilt resistance were mapped on four chromosomes. One major QTL, qBWA12, with LOD score of 32.8-66.0 and PVE of 31.2-44.8%, was stably detected in all four development stages investigated over the 3 trial years. Additionally, qBWA12 spanned a 2.7 cM region, corresponding to approximately 0.4 Mb and was fine mapped to a 216.7 kb region by applying KASP markers that were polymorphic between the two parents based on whole-genome resequencing data. In a large collection of breeding and germplasm lines, it was proved that KASP marker A12.4097252 can be applied for the marker-assisted breeding to develop peanut varieties resistant to bacterial wilt. Of the 19 candidate genes in the region covered by qBWA12, nine NBS-LRR genes should be further investigated regarding their potential contribution to the resistance of peanut against bacterial wilt.


Asunto(s)
Arachis , Resistencia a la Enfermedad , Arachis/genética , Arachis/microbiología , Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Fenotipo , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Polimorfismo de Nucleótido Simple
8.
J Org Chem ; 87(16): 11226-11230, 2022 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-35901265

RESUMEN

Herein, we report a strategically novel method for the efficient construction of indole skeletons using 2-phenylisoxazol-5-ones as the starting material. This reaction proceeds via Brønsted acid-promoted α-iminyl cation generation by N-O bond cleavage and a subsequent intramolecular cyclization to afford 1H-indole-3-carboxylic acid, which further undergoes decarboxylation to yield the final product. Control experiments show that N-O bond cleavage and intramolecular cyclization proceed so fast that the 1H-indole-3-carboxylic acid could be isolated in high yields even after 5-10 min. The substrate scope of this transformation is broad, and the desired products are obtained in moderate to good yields. The transition-metal-free reaction condition, CO2 as the sole byproduct, and good practicability add to the synthetic potential of this transformation in the pharmaceutical and flavor industries.


Asunto(s)
Androstenoles , Indoles , Ácidos/química , Cationes , Ciclización , Indoles/química
9.
Inorg Chem ; 61(16): 5977-5981, 2022 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-35394782

RESUMEN

This Communication demonstrates a novel and in situ simultaneous cavitation-doping (SCD) approach to construct bimetallic metal-doped cobalt metal-organic framework hollow nanospheres (CoM-MOF HNSs, with M = Ru or Fe). The key point of the SCD approach is the careful balance between the kinetics of Co-MOF being etched and the coordinative growth of a more stable CoM-MOF shell induced by Lewis acid (MCl3, with M = Ru or Fe). Our work provides a new method to synthesize bimetallic hollow MOFs and benefits the development of electrocatalysts.

10.
BMC Plant Biol ; 21(1): 568, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34861823

RESUMEN

BACKGROUND: The determinate growth habits is beneficial for plant architecture modification and the development of crops cultivars suited to mechanized production systems. Which play an important role in the genetic improvement of crops. In Brassica napus, a determinate inflorescence strain (4769) has been discovered among doubled haploid (DH) lines obtained from a spring B. napus × winter B. napus cross, but there are few reports on it. We fine mapped a determinate inflorescence locus, and evaluated the effect of the determinate growth habit on agronomic traits. RESULTS: In this study, we assessed the effect of the determinate growth habit on agronomic traits. The results showed that determinacy is beneficial for reducing plant height and flowering time, advancing maturity, enhancing lodging resistance, increasing plant branches and maintaining productivity. Genetic analysis in the determinate (4769) and indeterminate (2982) genotypes revealed that two independently inherited recessive genes (Bnsdt1, Bnsdt2) are responsible for this determinate growth trait. Bnsdt2 was subsequently mapped in BC2 and BC3 populations derived from the combination 2982 × 4769. Bnsdt2 could be delimited to an approximately 122.9 kb region between 68,586.2 kb and 68,709.1 kb on C09. BLAST analysis of these candidate intervals showed that chrC09g006434 (BnaC09.TFL1) is homologous to TFL1 of A. thaliana. Sequence analysis of two alleles identified two non-synonymous SNPs (T136C, G141C) in the first exon of BnaC09.TFL1, resulting in two amino acid substitutions (Phe46Leu, Leu47Phe). Subsequently, qRT-PCR revealed that BnaC09.TFL1 expression in shoot apexes was significantly higher in NIL-4769 than in 4769, suggesting its essential role in sustaining the indeterminate growth habit. CONCLUSIONS: In this study, the novel locus Bnsdt2, a recessive genes for determinate inflorescence in B. napus, was fine-mapped to a 68,586.2 kb - 68,709.1 kb interval on C09. The annotated genes chrC09g006434 (BnaC09.TFL1) that may be responsible for inflorescence traits were found.


Asunto(s)
Brassica napus/crecimiento & desarrollo , Brassica napus/genética , Regulación del Desarrollo de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Proteínas de Plantas/metabolismo , Flores/crecimiento & desarrollo , Haploidia , Proteínas de Plantas/genética
11.
Inorg Chem ; 60(7): 4366-4370, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33764045

RESUMEN

Controlling the morphology of highly homogeneous nanoribbons is one of the main goals for synthesizing catalysts with excellent activity and durability. In this Communication, platinum (Pt) nanoribbons were synthesized by a one-pot method. We used ammonium fluoride (NH4F) as the regulator, under 8 atm of hydrogen (H2), to synthesize zigzag-shaped two-dimensional Pt nanoribbons. Benefiting from their unique morphology, the Pt nanoribbons display superior electrocatalytic activity and stability.

12.
Ann Hum Biol ; 48(2): 157-159, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33487040

RESUMEN

The Shandong Peninsula is the largest peninsula in China and has played a vital part in Chinese civilisation. The ancient independent Laizi kingdom was located on the Shandong peninsula. While large demographic changes have happened at this peninsula throughout history, the genetic landscape of modern populations on this peninsula has never been clarified. The aims of our study were to investigate population genetic characteristics of the populations on the Shandong peninsula and to reveal their genetic affinities with other populations around the world. Allele frequencies, Hardy-Weinberg equilibrium, and forensic parameters of 15 autosomal STRs in the AmpFlSTR® Identifiler system were obtained from the studied populations with 2441 individuals in total. Allele frequencies were used to reveal the phylogenetic relationships among 287 worldwide populations. The combined power of discrimination (CPD) and the combined power of exclusion (CPE) in the whole of the Han population on the Shandong Peninsula were 0.999999999999999983 and 0.999998155, respectively. The 15 autosomal loci were polymorphic and informative among our studied populations. Genetic homogeneities were revealed between the modern populations on the Shandong Peninsula and Han nationalities from Northeastern China as well as East China.


Asunto(s)
Frecuencia de los Genes , Variación Genética , Repeticiones de Microsatélite , China
13.
Angew Chem Int Ed Engl ; 60(37): 20237-20242, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34191389

RESUMEN

Selective C-F bond functionalization of CF3 group represents an appealing strategy for the incorporation of pharmaceutically privileged difluoromethylene moiety. Despite the recent significant advancement attained in the functionalization of Ar-CF3 molecules, prescriptions amenable for alkenyl-CF3 congeners remain sufficiently inadequate. Herein, we report a strategically novel protocol for the C-F bond elaboration of trifluoromethylalkene derivatives. By using readily available allyl metallics as nucleophilic coupling partner, the present reaction enables an expedient construction of structurally diversified CF2 -bridged 1,5-dienes. Furthermore, the exquisite selectivity observed in this transformation is revealed to be based on the underlying mechanism that consists of a cascade of nucleophilic SN 2' defluorinative allylation and electronically promoted Cope rearrangement.

14.
BMC Plant Biol ; 20(1): 511, 2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-33167895

RESUMEN

BACKGROUND: Chlorophyll is the most important factor enabling plants to absorb, transfer and transform light energy and plays an important role in yield formation. Brassica napus is one of the most important oil crops. Breeding Brassica napus for high light efficiency by improving photosynthetic efficiency has considerable social and economic value. In Brassica napus, there have been studies of the initial location of chlorophyll in seed embryos and pericarps, but there are few reports on the fine mapping of chlorophyll QTLs. We constructed near-isogenic lines (NIL), fine-mapped a chlorophyll locus, and evaluated the effect of this dominant locus on agronomic traits. RESULTS: The cqSPDA2 locus was mapped to an interval of 21.87-22.91 Mb on the chromosome A02 of Brassica napus using doubled haploid (DH) lines. To fine-map cqSPDA2, we built NIL and designed Indel primers covering the mapping interval. The 469 individuals in the BC3F2 population were analyzed using these indel primers. Among these indel primers, 15 could narrow the mapping interval to 188 kb between Indel3 and Indel15. Next, 16 indel primers and 19 SSR primers were designed within the new narrower mapping interval, and 5 of the primer-amplified fragments were found to be polymorphic and tightly linked to the cqSPDA2 locus in the BC4F2 population. The mapping interval was narrowed to 152 kb on A02 between SSR2 and Indel15. By gene expression analysis, we found three annotated genes in the mapping interval, including BnaA02g30260D, BnaA02g30290D and BnaA02g30310D, which may be responsible for chlorophyll synthesis. CONCLUSIONS: The locus cqSPDA2, a dominant QTL for chlorophyll content in Brassica napus, was fine-mapped to a 21.89-22.04 Mb interval on A02. Three annotated genes (BnaA02g30260D, BnaA02g30290D and BnaA02g30310D) that may be responsible for chlorophyll synthesis were found.


Asunto(s)
Brassica napus/genética , Brassica napus/metabolismo , Clorofila/metabolismo , Mapeo Cromosómico , Genes de Plantas , Fotosíntesis/genética , Sitios de Carácter Cuantitativo , Clorofila/genética , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Fenotipo
15.
Ann Hum Biol ; 47(5): 472-477, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32342713

RESUMEN

BACKGROUND: The population genetics investigation of STR loci in specific populations is the basic premise for forensic practice, and the AmpFlSTRTM IdentifilerTM Plus kit is still widely used in most forensic DNA laboratories. AIM: To obtain more reliable and accurate population genetic data of 15 autosomal STRs in the Shandong Han population and explore the genetic relationship with 25 neighbouring Chinese populations. SUBJECTS AND METHODS: A total of 5356 unrelated Chinese Han individuals from Shandong Province were genotyped using the IdentifilerTM Plus Kit. Allele frequencies and corresponding forensic statistical parameters were calculated. Population comparisons were further explored through the neighbour-joining tree and multidimensional scaling analysis. RESULTS: A total of 217 alleles were calculated, the allele frequencies spanned from 0.0001 to 0.5340. The combined discrimination power (CDP) and the combined probability of paternity (CPE) of 15 STR loci were 0.99999999999999998755 and 0.999994524, respectively. Population comparisons demonstrated that Shandong Han have genetic homogeneity with most Sino-Tibetan populations. CONCLUSIONS: Our study updates the Shandong Han population database with a large sample size. These 15 STR loci in the Shandong Han population are more polymorphic and discriminatory than shown in previous data, which could be more applicable to personal identification and paternity testing, as well other population genetics studies.


Asunto(s)
Frecuencia de los Genes , Genotipo , Repeticiones de Microsatélite , China/etnología
16.
Angew Chem Int Ed Engl ; 58(12): 3918-3922, 2019 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-30694598

RESUMEN

A novel strategy for the expedient construction of CF3 -embeded tertiary/quarternary carbon centers was developed by taking advantage of photoredox catalysis. Thanks to a key step of single-electron oxidation, electron-rich gem-difluoroalkenes, which otherwise are essentially reluctant towards F-nucleoplilic addition, now readily participate in this fluoroallylation reaction. Furthermore, this strategy provides an elegant example for the generation, as well as functionalization, of α-CF3 -substituted benzylic radical intermediates using cheap and readily available starting materials.

17.
Angew Chem Int Ed Engl ; 58(52): 19027-19033, 2019 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-31617301

RESUMEN

Water-splitting photoanodes based on semiconductor materials typically require a dopant in the structure and co-catalysts on the surface to overcome the problems of charge recombination and high catalytic barrier. Unlike these conventional strategies, a simple treatment is reported that involves soaking a sample of pristine BiVO4 in a borate buffer solution. This modifies the catalytic local environment of BiVO4 by the introduction of a borate moiety at the molecular level. The self-anchored borate plays the role of a passivator in reducing the surface charge recombination as well as that of a ligand in modifying the catalytic site to facilitate faster water oxidation. The modified BiVO4 photoanode, without typical doping or catalyst modification, achieved a photocurrent density of 3.5 mA cm-2 at 1.23 V and a cathodically shifted onset potential of 250 mV. This work provides an extremely simple method to improve the intrinsic photoelectrochemical performance of BiVO4 photoanodes.

18.
J Am Chem Soc ; 140(34): 10695-10699, 2018 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-30102522

RESUMEN

Herein, we report the first example of group transfer radical addition of O-vinylhydroxylamine derivatives onto unactivated alkenes. By utilizing O-vinylhydroxylamine derivatives as both the N- and C-donors, this reaction enables intermolecular carboamination of unactivated alkenes in an atom economical fashion. As the process is initiated through N-radical addition followed by C-transfer, linear carboamination products are afforded. This differs from canonical radical carbofunctionalization of olefins, which typically favors branched product owing to initiation by C-radical addition.

19.
Nanotechnology ; 29(30): 305503, 2018 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-29741497

RESUMEN

Carbon nanotubes form a complex network in nanocomposites. In the network, the configuration of the nanotubes is various. A carbon nanotube may be curled or straight, and it may be parallel or crossed to another. As a result, carbon nanotube-based composites exhibit integrated characteristics of inductor, capacitor and resistor. In this work, it is hypothesised that carbon nanotube-based composites all adhere to a RLC interior circuit. To verify the hypothesis, three different composites, viz multi-walled carbon nanotube/polyvinylidene fluoride (MWCNT/PVDF), multi-walled carbon nanotube/epoxy (MWCNT/EP), multi-walled carbon nanotube/polydimethylsiloxane (MWCNT/PDMS) were fabricated and tested. The resistances and the dielectric loss tangent (tanδ) of the materials were measured in direct and alternating currents. The measurement shows that the value of tanδ is highly affected by the volume fraction of MWCNT in the composites. The experimental results prove that the proposed RLC equivalent circuit model can fully describe the electrical properties of the MWCNT network in nanocomposites. The RLC model provides a new route to detect the inductance and capacitance of carbon nanotubes. Moreover, the model also indicates that the carbon nanotube-based composite films may be used to develop wireless strain sensors.

20.
Exp Dermatol ; 26(4): 368-374, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27943426

RESUMEN

Psoriasis is a common inflammatory skin disease, but the exact pathogenesis is largely unknown. Interleukin-22 (IL-22) has demonstrated its vital role in T-cell-mediated immune response by interacting with keratinocytes in the pathogenesis of psoriasis. Here, we showed the differentially expressed miRNAs and their potential targets in HaCaT cells stimulated by IL-22 using miRNA and mRNA microarrays. We revealed a total of 20 significantly changed (more than twofold) miRNAs in HaCaT cells and validated the results with quantitative reverse transcriptase PCR (qRT-PCR). We demonstrated that miR-122-5p was up-regulated both in HaCaT cells stimulated by IL-22 and in psoriatic lesions. Then, we aimed to investigate the biological roles and potential mechanism of miR-122-5p in keratinocytes. As a result, CCK-8 assay indicated that overexpression of miR-122-5p in keratinocytes promoted proliferation and conversely inhibition of endogenous miR-122-5p suppressed proliferation. According to the microarray analysis, we assumed that Sprouty2 (Spry2), a negative regulator of extracellular signal regulated kinase/mitogen-activated protein kinase signalling pathway, was a direct target gene of miR-122-5p. We found that the staining of Spry2 in cytoplasm was mainly localized in both basal and suprabasal layers of epidermis and showed a markedly decreased expression in psoriasis than in normal control by immunohistochemistry. Luciferase reporter and Western blot assays in HaCaT cells demonstrated that Spry2 was a direct target gene of miR-122-5p. In conclusion, IL-22-induced miR-122-5p promotes keratinocyte proliferation possibly by downregulating the expression of Spry2 thus playing important roles in the pathogenesis of psoriasis.


Asunto(s)
Proliferación Celular/genética , Interleucinas/farmacología , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de la Membrana/genética , MicroARNs/genética , Psoriasis/genética , ARN Mensajero/análisis , Regiones no Traducidas 3' , Regulación hacia Abajo/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Queratinocitos/fisiología , Proteínas de la Membrana/metabolismo , MicroARNs/análisis , MicroARNs/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Psoriasis/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Interleucina-22
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