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1.
J Hazard Mater ; 469: 134055, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38503215

RESUMO

The purification of oxygenated volatile organic compounds VOCs (OVOCs), important precursors of ozone and particulate matters, has triggered intensive research interests. UiO-66 with high photocatalytic activity have shown great potential. However, the lack of active sites severely limited the trapping and degradation of OVOCs. Herein, reo-UiO-66 with increased specific surface area, hierarchical porous structure and tunable acidic/basic sites was synthesized by simply adding water as the modulator. XRD, TGA and FTIR results confirmed the formation of reo-defects, which significantly affected the surface hydrophilicity and active sites of UiO-66. The adsorption of Lewis acidic acetaldehyde was enhanced by 265 times with coordinative unsaturated Zr acting as the dominant adsorption sites. The degradation efficiency of typical OVOCs (acetaldehyde and acetone) increased from 0% and 25% to 50% and 73%, respectively. This work provided a facile method to modulate the micro-environment in MOFs for the efficient capture and catalytic purification of OVOCs.

2.
ACS Appl Mater Interfaces ; 14(47): 52894-52906, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36378027

RESUMO

The implantation of metal nanoparticles (MNPs) into metal-organic framework (MOF) hosts is a promising means to prepare high-performance photocatalysts for the degradation of gas pollutants. However, the uniform encapsulation of MNPs in MOFs is still challenging. Herein, a facile "quasi-in situ" encapsulation method is proposed by utilizing the spatial confinement effect of the colloidal network formed during the synthesis of the MIL-100(Fe) monolith [noted as m-MIL-100(Fe)]. Highly dispersed Ag NPs with an average diameter of ∼2 nm are encapsulated in the MIL-100(Fe) monolith to form a unique "watermelon-seed" structure, which ensures the large contact area between the two components and protects Ag NPs from being oxidized. The fast charge transfer between m-MIL-100(Fe) and Ag NPs enables the spatial separation of electron-hole pairs and promotes the generation of oxidative radicals. Compared with pristine m-MIL-100(Fe), the 0.2 wt % Ag@m-MIL-100(Fe) composite shows obviously enhanced photodegradation efficiencies for flowing o-xylene under both xenon (∼97%) and visible light (∼80.0%) with high stability. This work not only provides a promising Ag@m-MIL-100(Fe) material for eliminating air pollutants but also gives a versatile means for the design and synthesis of nanoparticles@MOFs composites with desired performance.

3.
Front Cell Dev Biol ; 9: 671170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568312

RESUMO

MicroRNAs let-7c and let-7f, two members of the let-7 family, were involved in regulating osteoblast differentiation and have an important role in bone formation. Let-7e-5p, which also belonged to the let-7 family, presented in the differentiation of adipose-derived stem cells and mouse embryonic stem cells. However, the role of let-7e-5p in osteoblast differentiation was unclear. Thus, this study aimed to elucidate the function of let-7e-5p in osteoblast differentiation and its mechanism. Firstly, we found that the let-7e-5p mimic promoted osteoblast differentiation but not the proliferation of MC3T3-E1 cells by positively regulating the expression levels of osteogenic-associated genes (RUNX2, OCN, OPN, and OSX), the activity of ALP, and formation of mineralized nodules. Moreover, we ascertained that the let-7e-5p mimic downregulated the post-transcriptional expression of SOCS1 by specifically binding to the 3' untranslated region of SOCS1 mRNA. Also, let-7e-5p-induced SOCS1 downregulation increased the protein levels of p-STAT5 and IGF-1, which were both modulated by SOCS1 molecules. Furthermore, let-7e-5p abrogated the inhibition of osteogenic differentiation mediated by SOCS1 overexpression. Therefore, these results suggested that let-7e-5p regulated the differentiation of MC3T3-E1 cells through the JAK2/STAT5 pathway to upregulate IGF-1 gene expression by inhibiting SOCS1. These findings may provide a new insight into the regulatory role of let-7e-5p in osteogenic differentiation and imply the existence of a novel mechanism underlying let-7e-5p-mediated osteogenic differentiation.

4.
Front Genet ; 12: 607910, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33692824

RESUMO

Maternally expressed gene 3 (MEG3) is a long non-coding RNA that is a crucial regulator of skeletal muscle development. Some single-nucleotide polymorphism (SNP) mutants in MEG3 had strong associations with meat quality traits. Nevertheless, the function and mechanism of MEG3 mutants on porcine skeletal muscle development have not yet been well-demonstrated. In this study, eight SNPs were identified in MEG3 of fat- and lean-type pig breeds. Four of these SNPs (g.3087C > T, g.3108C > T, g.3398C > T, and g.3971A > C) were significantly associated with meat quality and consisted of the CCCA haplotype for fat-type pigs and the TTCC haplotype for lean-type pigs. Quantitative real-time PCR results showed that the expression of MEG3-TTCC was higher than that of MEG3-CCCA in transcription level (P < 0.01). The stability assay showed that the lncRNA stability of MEG3-TTCC was lower than that of MEG3-CCCA (P < 0.05). Furthermore, the results of qRT-PCR, Western blot, and Cell Counting Kit-8 assays demonstrated that the overexpression of MEG3-TTCC more significantly inhibited the proliferation of porcine skeletal muscle satellite cells (SCs) than that of MEG3-CCCA (P < 0.05). Moreover, the overexpression of MEG3-TTCC more significantly promoted the differentiation of SCs than that of MEG3-CCCA (P < 0.05). The Western blot assay suggested that the overexpression of MEG3-TTCC and MEG3-CCCA inhibited the proliferation of SCs by inhibiting PI3K/AKT and MAPK/ERK1/2 signaling pathways. The overexpression of the two haplotypes also promoted the differentiation of SCs by activating the JAK2/STAT3 signaling pathway in different degrees. These data are valuable for further studies on understanding the crucial role of lncRNAs in skeletal muscle development.

5.
Front Cell Dev Biol ; 8: 623, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754602

RESUMO

Owing to the wide application of miniature pigs in biomedicine, the formation mechanism of its short stature must be elucidated. The insulin-like growth factor 1 receptor (IGF-1R), which receives signals through the extracellular domain (ECD) binding with ligands, is crucial in regulating cell growth and bone matrix mineralization. In this study, two haplotypes of Igf1r with four synonymous mutations in the coding sequences of IGF-1R ECD between large pigs (LP) and Bama pigs (BM) were stably expressed in the Igf1r-knockout MC3T3-E1 cells and named as MC3T3-LP cells (LP group) and MC3T3-BM cells (BM group), respectively. IGF-1R expression was lower in the BM group than in the LP group both in terms of transcription and translation levels, and IGF-1R expression inhibited cell proliferation. In addition, IGF-1R expression in the BM group promoted early-stage differentiation but delayed late-stage differentiation, which not only suppressed the expression of bone-related factors but also reduced alkaline phosphatase activity and calcium deposition. Moreover, different haplotypes of Igf1r changed the stability and conformation of the protein, further affecting the binding with IGF-1. Our data indicated that the four synonymous mutations of IGF1R ECD encoded by affect gene transcription and translation, thereby further leading to differences in the downstream pathways and functional changes of osteoblasts.

6.
RNA Biol ; 17(12): 1754-1766, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32508238

RESUMO

Growth hormone (GH), whose synthesis and release are mainly regulated by intracellular signals mediated by growth hormone-releasing hormone receptor (GHRHR), is one of the major pituitary hormones and critical regulators of organism growth, metabolism, and immunoregulation. Pig GHRHR splice variants (SVs) may activate different signalling pathways via the variable C-terminal by alternative splicing, and SVs have the potential to change microRNA (miRNA) binding sites. In this study, we first confirmed the existence of pig GHRHR SVs (i.e., GHRHR, GHRHR SV1 and SV2) and demonstrated the inhibitory effects of critical pituitary miRNAs (i.e., let-7e and miR-328-5p) on GH synthesis and cell proliferation of primary pituitary cells. The SVs of GHRHR targeted by let-7e and miR-328-5p were predicted via bioinformatics analysis and verified by performing dual-luciferase reporter assays and detecting the expression of target transcripts. The differential responses of let-7e, and miR-328-5p to GH-releasing hormone and the changes in signalling pathways mediated by GHRHR suggested that let-7e and miR-328-5p were involved in GH synthesis mediated by GHRHR SVs, indicating that the two miRNAs played different roles by different ways. Finally, results showed that the protein coded by the GHRHR transcript regulated GH through the NO/NOS signalling pathway, whereas that coded by SV1 and SV2 regulated GH through the PKA/CREB signalling pathway, which was confirmed by the changes in signalling pathways after transfecting the expression vectors of GHRHR SVs to GH3 cells. To the best of our knowledge, this paper is the first to report pituitary miRNAs regulate GH synthesis by targeting the different SVs of GHRHR.


Assuntos
Processamento Alternativo , Hormônio do Crescimento/metabolismo , MicroRNAs/metabolismo , Hipófise/metabolismo , Interferência de RNA , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Transdução de Sinais , Animais , Linhagem Celular , Proliferação de Células , Sobrevivência Celular/genética , Biologia Computacional , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Hormônio do Crescimento/genética , MicroRNAs/genética , Óxido Nítrico/metabolismo , Suínos
7.
J Colloid Interface Sci ; 572: 374-383, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32272312

RESUMO

Most studies on the photodegradation of volatile organic compounds (VOCs) have focused on the synthesis of efficient photocatalysts. However, little attention has been paid to the band bending change of semiconductive photocatalysts after the adsorption of VOCs. Herein, we first disclose how the adsorption of two typical VOCs influences the band bending of P-type rutile TiO2 and consequently changes the amount of reactive radicals. This provides a new way to understand the experimental phenomenon of heterogeneous reactions. Theoretical computations of the adsorption model and zeta potential tests both verified that o-xylene is an acceptor molecule when it adsorbs on the TiO2 surface, and it tends to attract electrons from TiO2. In contrast, acetaldehyde is a donor molecule. A distinct electron transfer direction between TiO2 and adsorbed molecules (o-xylene and acetaldehyde) induces a different band bending degree. O-xylene adsorption alleviates the downward band bending of TiO2 itself, whereas acetaldehyde adsorption strengthens the downward band bending. The probability of electrons and holes reaching the TiO2 surface is influenced by this change, which has a considerable influence on the generation of active radicals. Consequently, o-xylene adsorption leads to more hydroxyl radical generation, and acetaldehyde adsorption results in less hydroxyl radical generation. As a result, hydroxyl radicals play the predominant role in the degradation of o-xylene, whereas the photocatalysis of acetaldehyde is dominant for superoxide radicals. In addition, the band bending of a semiconductor induced by gaseous molecule adsorption has the potential for application in gas sensors to improve sensitivity.

8.
Domest Anim Endocrinol ; 72: 106430, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32171113

RESUMO

The kidney of miniature pigs has been considered the most likely potential kidney source for patients needing kidney transplantation. Insulin-like growth factor 1 (IGF-1) is involved in regulating the growth of miniature pigs and inducing growth of kidneys. There are evidences showing that the SNPs in the 3'UTR of a gene may affect the gene expression by affecting the binding to a miRNA target site. In this study, one SNP (rs34142920) was screened in the IGF-1 3'UTR between 2 different body types of porcine breeds, Bama Xiang (BX) pigs, a miniature pig breed, and Large White (LW) pigs by sequencing. The secondary structure of the IGF-1 3'UTR mRNA containing the SNP in BX pigs is different from that of LW pigs. We then verified that there was a porcine miRNA (miR-new14) binding to this SNP in the 3'UTR of IGF-1 via cotransfecting the 3'UTR from the 2 breeds and miR-new14. We further found that the SNP downregulated mRNA and protein levels of IGF-1 by affecting the binding of miR-new14. To understand the function of miR-new14 in porcine kidney (PK-15) cells and its mechanism, cell proliferation and cell apoptosis assays were employed and results showed that proliferation viability of PK-15 cells was weakened and the apoptotic percentage of PK-15 cells was higher in the miR-new14 group. Porcine miRNA reduced the mRNA expression of AKT/ERK and protein levels of p-AKT/p-ERK. These results suggested that the expression of IGF-1 is influenced by this SNP and miR-new14 and that miR-new14 may suppress cell proliferation and promote cell apoptosis in PK-15 cells through regulating AKT and ERK signaling pathways, in which IGF-1 is involved.


Assuntos
Regiões 3' não Traduzidas , Regulação da Expressão Gênica/fisiologia , Fator de Crescimento Insulin-Like I/metabolismo , MicroRNAs/metabolismo , Polimorfismo de Nucleotídeo Único , Suínos , Animais , Apoptose , Linhagem Celular , Proliferação de Células , Fator de Crescimento Insulin-Like I/genética , MicroRNAs/genética
9.
Int J Biol Macromol ; 152: 147-153, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32109480

RESUMO

Miniature pigs are regarded as ideal organ donors for xenotransplantation into humans. Elucidating the formation mechanism of miniature pigs is important. The insulin-like growth factor 1 receptor (IGF-1R) is crucial in the regulation of cell proliferation and organismal growth. According to our previous research, the IGF-1R expression levels between large and miniature pigs showed different profiles in liver and muscle tissues. Here, five synonymous mutations of IGF-1R in the coding sequence (CDS) of intracellular domain (ICD) between large and miniature pigs were analysed by constructing expression vectors of two haplotypes and named pcDNA3.1-LP (with the CDS of IGF-1R ICD of Large White pigs, LP group) and pcDNA3.1-BM (with the CDS of IGF-1R ICD of Bama Xiang pigs, BM group). The IGF-1R of the BM group was expressed lower than that of the LP group in transcription, translation and autophosphorylation levels. The IGF-1R of the BM group also down-regulated the protein levels of p-AKT/p-ERK than that of the LP group. PK-15 and C2C12 cell proliferation were detected to further understand the function of the haplotype. Results showed that the proliferation viability of PK-15 and C2C12 cells weakened in the BM group. Moreover, the mRNA and protein stabilities of the BM group were higher than those of the LP group. Our data indicated that two haplotypes of IGF-1R CDS in ICD between large and miniature pigs altered IGF-1R expression and down-regulated AKT and ERK signalling pathways at translation levels, resulting in an inhibitory effect on PK-15 and C2C12 cell proliferation.


Assuntos
Espaço Intracelular/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Mutação Silenciosa , Animais , Linhagem Celular , Proliferação de Células/genética , Loci Gênicos/genética , Haplótipos , Fosforilação/genética , Polimorfismo de Nucleotídeo Único , Domínios Proteicos , RNA Mensageiro/genética , Receptor IGF Tipo 1/química , Transdução de Sinais/genética , Suínos
10.
Reprod Domest Anim ; 55(3): 384-392, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31945221

RESUMO

Hypothalamic gonadotropin-releasing hormone (GnRH) controls the activity of hypothalamic-pituitary-gonadal axis and plays a key role in the reproductive performance of animals. In this study, five single nucleotide polymorphisms (SNPs), namely g.991T > C, g.1041T > C g.3424T > C, g.3462C > A and g.3463Inde A, were detected in the GnRH gene of 162 water buffaloes by Sanger sequencing. Each SNP was associated with more than two sperm quality traits of ejaculate volume, sperm concentration, post-thaw sperm motility and sperm abnormality. g.3424T > C and g.3462C > A were related to these four traits and had a remarkable effect on ejaculate volume. The three other SNPs were related to sperm concentration, post-thaw sperm motility and sperm abnormality. Moreover, six haplotypes (H1: TCCAI, H2: CTTC-, H3: TCCCI, H4: CTTA-, H5: CCTA- and H6: CTCC-) composed of five SNPs comprising seven different combined genotypes were generated by linkage disequilibrium analysis. Statistics followed by one-way ANOVA indicated that water buffaloes with the haplotype combination H1H1 had the highest genotypic frequency, and those with the H4H4 haplotype combination had the highest ejaculate volume. The sperm concentration of those with haplotype combination H1H5 was higher than that of the other genotypes. In summary, our study showed a remarkable association between the SNPs of GnRH and sperm quality traits of Chinese water buffalo.


Assuntos
Búfalos/genética , Hormônio Liberador de Gonadotropina/genética , Polimorfismo de Nucleotídeo Único , Análise do Sêmen , Animais , Búfalos/fisiologia , Ejaculação , Congelamento , Desequilíbrio de Ligação , Masculino , Preservação do Sêmen/veterinária , Contagem de Espermatozoides , Motilidade dos Espermatozoides/genética , Espermatozoides/anormalidades , Espermatozoides/fisiologia
11.
J Hazard Mater ; 380: 120814, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31325696

RESUMO

Although coupling reduced graphene oxide (RGO) with TiO2 is believed to enhance the photocatalysis through the light utilization, studies on its photothermal conversion effect are rarely reported. Herein, RGOP (reduced graphene oxide/P25) was synthesized to explore roles of the enhanced light adsorption and photothermal conversion in the photocatalytic process. It was found that although RGOP had increased absorbance, it actually possessed lower available light utilization compared with P25. In the synergistic effect of available light utilization, transfer resistance and hydrophilicity, RGOP exhibited less superoxide radicals but more hydroxyl radicals. In the presence of scavenger experiments, O2- was proved to play the predominant role in the photocatalytic process, while OH was the secondary one. In comparison to P25, the change of active radicals of RGOP was adverse to its photocatalysis. However, due to the superior adsorptive property of RGOP, it exhibited higher photocatalytic activity than P25. The improved photocatalytic activity of RGOP was ascribed to its superior adsorptive ability aside from active radicals (O2-, OH).

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