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1.
Int J Biol Macromol ; : 135001, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39182868

RESUMEN

This study reports the successful synthesis of flame-retardant and smoke-suppressing epoxy resin (EP) via bio-based polyelectrolyte flame retardants. Herein, a novel polyelectrolyte flame retardant was prepared from chitosan (CS) and hexa-(4-carboxyl-phenoxy)-cyclotriphosphazene (HCPCP) by acid-base neutralization reaction, which the HCPCP was synthesized with hexachlorocyclotriphosphazene (HCCP) and methyl p-hydroxybenzoate (MP) by nucleophilic substitution reaction. The combined effect of the addition on the flame retardant, smoke suppression and mechanical properties of EP samples were systematically investigated. The presence of this bio-based polyelectrolyte provided excellent smoke suppression and flame-retardant properties of the prepared EP. Among them, the peak heat release rate (PHRR), peak smoke production rate (PSPR) and total smoke production (TSP) of EP/9wt%3CS-HCPCP composite (the ratio of CS to HCPCP was 3: 7, and the dosage was 9 wt%) were reduced by 45.42 %, 41.66 % and 22.56 %, respectively. In addition, the EP/CS-HCPCP composites showed a 207.80 % enhancement in char residue compared to pure EP. These results suggest a green and cost-effective strategy for the production of flame-retardant, drip-proof and smoke-suppressed EP composites.

2.
Mol Cancer Res ; 22(8): 699-710, 2024 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-38639925

RESUMEN

Leptomeningeal metastasis (LM) is a devastating complication of advanced non-small cell lung cancer (NSCLC). Its diagnosis and monitoring can be challenging. Recently, extracellular vesicle (EV) miRNAs have become a new noninvasive diagnostic biomarker. The purpose of this study was to examine the clinical value and role of EV miRNAs in NSCLC-LM. Next-generation sequencing analysis revealed that miRNAs with differential expression of EVs in sera of patients with NSCLC with LM and non-LM were detected to identify biological markers for the diagnosis of LM. Cellular and in vivo experiments were conducted to explore the pathogenesis of EV miRNA promoting LM in NSCLC. In the present study, we first demonstrated that the serum level of EV-associated miR-374a-5p in patients with LM of lung cancer was much higher than that in patients without LM and was correlated with the survival time of patients with LM. Further studies showed that EV miR-374a-5p efficiently destroys tight junctions and the integrity of the cerebral microvascular endothelial cell barrier, resulting in increased blood-brain barrier permeability. Mechanistically, miR-374a-5p regulates the distribution of ZO1 and occludin in endothelial cells by targeting γ-adducin, increasing vascular permeability and promoting LM. Implications: These results suggest that serum NSCLC-derived EV miR-374a-5p is involved in premetastatic niche formation by regulating the permeability of the blood-brain barrier to promote NSCLC-LM and can be used as a blood biomarker for the diagnosis and prognosis of NSCLC-LM.


Asunto(s)
Barrera Hematoencefálica , Carcinoma de Pulmón de Células no Pequeñas , Vesículas Extracelulares , Neoplasias Pulmonares , MicroARNs , MicroARNs/genética , MicroARNs/sangre , MicroARNs/metabolismo , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Barrera Hematoencefálica/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/sangre , Animales , Ratones , Masculino , Femenino , Persona de Mediana Edad , Línea Celular Tumoral , Ratones Desnudos , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/secundario , Neoplasias Meníngeas/sangre , Neoplasias Meníngeas/metabolismo , Permeabilidad
3.
ACS EST Air ; 1(4): 247-258, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38633205

RESUMEN

The chemical and optical properties of secondary organic aerosols (SOA) have been widely studied through environmental chamber experiments, and some of the results have been parametrized in atmospheric models to help understand their radiative effects and climate influence. While most chamber studies investigate the aerosol formed from a single volatile organic compound (VOC), the potential interactions between reactive intermediates derived from VOC mixtures are not well understood. In this study, we investigated the SOA formed from pure and mixtures of anthropogenic (phenol and 1-methylnaphthalene) and/or biogenic (longifolene) VOCs using continuous-flow, high-NOx photooxidation chamber experiments to better mimic ambient conditions. SOA optical properties, including single scattering albedo (SSA), mass absorption coefficient (MAC), and refractive index (RI) at 375 nm, and chemical composition, including the formation of oxygenated organic compounds, organic-nitrogen compounds (including organonitrates and nitro-organics), and the molecular structure of the major chromophores, were explored. Additionally, the imaginary refractive index values of SOA in the multi-VOC system were predicted using a linear-combination assumption and compared with the measured values. When two VOCs were oxidized simultaneously, we found evidence for changes in SOA chemical composition compared to SOA formed from single-VOC systems, and this change led to nonlinear effects on SOA optical properties. The nonlinear effects were found to vary between different systems.

4.
J Imaging Inform Med ; 37(1): 374-385, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38343259

RESUMEN

Fully supervised medical image segmentation methods use pixel-level labels to achieve good results, but obtaining such large-scale, high-quality labels is cumbersome and time consuming. This study aimed to develop a weakly supervised model that only used image-level labels to achieve automatic segmentation of four types of uterine lesions and three types of normal tissues on magnetic resonance images. The MRI data of the patients were retrospectively collected from the database of our institution, and the T2-weighted sequence images were selected and only image-level annotations were made. The proposed two-stage model can be divided into four sequential parts: the pixel correlation module, the class re-activation map module, the inter-pixel relation network module, and the Deeplab v3 + module. The dice similarity coefficient (DSC), the Hausdorff distance (HD), and the average symmetric surface distance (ASSD) were employed to evaluate the performance of the model. The original dataset consisted of 85,730 images from 316 patients with four different types of lesions (i.e., endometrial cancer, uterine leiomyoma, endometrial polyps, and atypical hyperplasia of endometrium). A total number of 196, 57, and 63 patients were randomly selected for model training, validation, and testing. After being trained from scratch, the proposed model showed a good segmentation performance with an average DSC of 83.5%, HD of 29.3 mm, and ASSD of 8.83 mm, respectively. As far as the weakly supervised methods using only image-level labels are concerned, the performance of the proposed model is equivalent to the state-of-the-art weakly supervised methods.

5.
Chemosphere ; 346: 140521, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37925028

RESUMEN

The traditional method of preparing graphene will cause serious environmental pollution, and the combustion of polymer materials will seriously harm people's health. In this paper, a Cu-MOF-coated graphene composite flame retardant (G@Cu-MOF) rich in flame retardant elements such as B and N was synthesized through green mechanical ball milling method. Flame retardants reduce the threat to the environment and people's lives and property. After adding 6 wt% G@Cu-MOF, the peak heat release rate, total heat release rate, CO production and CO2 production of epoxy resin (EP) composite samples decreased by 55, 14, 59, and 55%, respectively. This type of Cu-MOF releases incombustible gases such as boron trifluoride (BF3) and ammonia (NH3) during combustion, diluting the concentration of combustible gases and producing copper borate in the condensed phase. Cu2+ is reduced to Cu, and boron compounds are converted into boron oxides. The thermal conductivity of graphene can reduce the temperature of the matrix, and has good flame retardancy. It synergistically acts with Cu-MOF to promote the formation of high-quality residual char, and can significantly inhibit the heat and smoke release of EP. It plays a role in flame retardancy and protecting the substrate from fire. This study provides a new approach for preparing graphene hybrid flame retardants through mechanical ball milling, in order to improve the flame retardancy of EP and suppress the release of smoke and toxic gases.


Asunto(s)
Retardadores de Llama , Grafito , Humanos , Humo , Cobre , Gases
6.
Mol Cancer ; 22(1): 179, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932766

RESUMEN

BACKGROUND: Noncoding RNAs such as circular RNAs (circRNAs) are abundant in the human body and influence the occurrence and development of various diseases. Non-small cell lung cancer (NSCLC) is one of the most common malignant cancers. Information on the functions and mechanism of circRNAs in lung cancer is limited; thus, the topic needs more exploration. The purpose of this study was to identify aberrantly expressed circRNAs in lung cancer, unravel their roles in NSCLC progression, and provide new targets for lung cancer diagnosis and therapy. METHODS: High-throughput sequencing was used to analyze differential circRNA expression in patients with lung cancer. qRT‒PCR was used to determine the level of circHERC1 in lung cancer tissues and plasma samples. Gain- and loss-of-function experiments were implemented to observe the impacts of circHERC1 on the growth, invasion, and metastasis of lung cancer cells in vitro and in vivo. Mechanistically, dual luciferase reporter assays, fluorescence in situ hybridization (FISH), RNA immunoprecipitation (RIP) and RNA pull-down experiments were performed to confirm the underlying mechanisms of circHERC1. Nucleocytoplasmic localization of FOXO1 was determined by nucleocytoplasmic isolation and immunofluorescence. The interaction of circHERC1 with FOXO1 was verified by RNA pull-down, RNA immunoprecipitation (RIP) and western blot assays. The proliferation and migration of circHERC1 in vivo were verified by subcutaneous and tail vein injection in nude mice. RESULTS: CircHERC1 was significantly upregulated in lung cancer tissues and cells, ectopic expression of circHERC1 strikingly facilitated the proliferation, invasion and metastasis, and inhibited the apoptosis of lung cancer cells in vitro and in vivo. However, knockdown of circHERC1 exerted the opposite effects. CircHERC1 was mainly distributed in the cytoplasm. Further mechanistic research indicated that circHERC1 acted as a competing endogenous RNA of miR-142-3p to relieve the repressive effect of miR-142-3p on its target HMGB1, activating the MAPK/ERK and NF-κB pathways and promoting cell migration and invasion. More importantly, we found that circHERC1 could bind FOXO1 and sequester it in the cytoplasm, adjusting the feedback AKT pathway. The accumulation of FOXO1 in the cytosol and nuclear exclusion promoted cell proliferation and inhibited apoptosis. CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential prognostic biomarker and therapeutic target for NSCLC. CONCLUSIONS: CircHERC1 is a new circRNA that promotes tumor function in NSCLC and may serve as a potential diagnosis biomarker and therapeutic target for NSCLC. Our findings indicate that circHERC1 facilitates the invasion and metastasis of NSCLC cells by regulating the miR-142-3p/HMGB1 axis and activating the MAPK/ERK and NF-κB pathways. In addition, circHERC1 can promote cell proliferation and inhibit apoptosis by sequestering FOXO1 in the cytoplasm to regulate AKT activity and BIM transcription.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Proteína Forkhead Box O1 , Proteína HMGB1 , Neoplasias Pulmonares , MicroARNs , ARN Circular , Animales , Humanos , Ratones , Biomarcadores , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Citoplasma/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteína HMGB1/metabolismo , Hibridación Fluorescente in Situ , Neoplasias Pulmonares/genética , Ratones Desnudos , MicroARNs/genética , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Circular/genética , Proteína Forkhead Box O1/metabolismo , Ubiquitina-Proteína Ligasas/genética
7.
Apoptosis ; 28(3-4): 471-484, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36574090

RESUMEN

Circular RNAs (circRNAs) are a specialized circular structure, are deregulated in cancers and play essential roles in biological processes involved in tumor progression. However, the mechanism by which circRNAs affect lung tumorigenesis and progression remains largely unexplored. To investigate the role of circRNA in lung cancer, circRNA expression profile was screened by bioinformatics analysis. The levels of circTAB2, miR-3142, and GLIS family zinc finger 2 (GLIS2) were measured by quantitate real-time (qRT-PCR) or western blot. Cell proliferation, apoptosis, migration and invasion were detected by EdU, flow cytometry, and transwell assays, respectively. Bioinformatics, western blot, RIP, pull down, dual luciferase reporter and rescue experiments were used to verify the direct relationship between miR-3142 and circTAB2 or GLIS2. The xenograft assays were used to assess the role of circTAB2 in vivo.CircTAB2 exhibited low expression in cancer tissues. Gain and loss-of-function assays indicated that circTAB2 could inhibit cell proliferation, migration and invasion. Functional studies revealed that circTAB2 acted as a miRNA sponge, directly interacted with miR-3142 and consequently regulated GLIS2 /AKT. Taken together, circTAB2 serves as an inhibitory role in lung cancer through a novel circTAB2 /miR-3142 /GLIS2 /AKT pathway and could be exploited a novel marker in lung cancer.


Asunto(s)
Neoplasias Pulmonares , MicroARNs , Humanos , Apoptosis , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/patología , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Circular/genética , ARN Circular/metabolismo
8.
ACS Infect Dis ; 8(10): 2019-2027, 2022 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-36048501

RESUMEN

ATP provides energy in the biosynthesis of cellular metabolites as well as regulates protein functions through phosphorylation. Many ATP-dependent enzymes are antibacterial and anticancer targets including human kinases acted on by most of the successful drugs. In search of new chemotherapeutics for tuberculosis (TB), we screened repurposing compounds against the essential glutamine synthase (GlnA1) of Mycobacterium tuberculosis (Mtb) and identified linsitinib, a clinical-stage drug originally targeting kinase IGF1R/IR as a potent GlnA1 inhibitor. Linsitinib has direct antimycobacterial activity. Biochemical, molecular modeling, and target engagement analyses revealed the inhibition is ATP-competitive and specific in Mtb. Linsitinib also improves autophagy flux in both Mtb-infected and uninfected THP1 macrophages, as demonstrated by the decreased p-mTOR and p62 and the increased lipid-bound LC3B-II and autophagosome forming puncta. Linsitinib-mediated autophagy reduces intracellular growth of wild-type and isoniazid-resistant Mtb alone or in combination with bedaquiline. We have demonstrated that an IGF-IR/IR inhibitor can potentially be used to treat TB. Our study reinforces the concept of targeting ATP-dependent enzymes for novel anti-TB therapy.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Adenosina Trifosfato/metabolismo , Antibacterianos/metabolismo , Glutamina/metabolismo , Humanos , Imidazoles , Isoniazida , Lípidos , Mycobacterium tuberculosis/metabolismo , Inhibidores de Proteínas Quinasas , Pirazinas , Receptor IGF Tipo 1/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Tuberculosis/tratamiento farmacológico , Tuberculosis/microbiología
9.
Hortic Res ; 9: uhac071, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35734379

RESUMEN

Cineraria (Senecio cruentus) is an ornamental plant with pure colour and bicolour cultivars, widely used for landscaping. Anthocyanin biosynthesis influences coloration patterns in cineraria. However, how anthocyanins accumulate and distribute in cineraria is poorly understood. This study investigated the molecular mechanisms underlying anthocyanin biosynthesis and bicolour formation in cineraria using pure colour and bicolour cultivars. Transcriptome and gene expression analysis showed that five genes, ScCHS2, ScF3H1, ScDFR3, ScANS, and ScbHLH17, were inhibited in the white cultivar and colourless regions of bicolour cultivars. In contrast, two MADS-box genes, ScAG and ScAGL11, showed significantly higher expression in the colourless regions of bicolour cultivars. ScAG and ScAGL11 were localized in the nucleus and co-expressed with the bicolour trait. Further functional analysis verified that ScAG inhibits anthocyanin accumulation in tobacco (Nicotiana tabacum). However, virus-induced gene silencing (VIGS) experiments showed that silencing of ScAG and ScAGL11 increases anthocyanin content in cineraria leaves. Similar results were observed when ScAG and ScAGL11 were silenced in the cineraria capitulum, accompanied by the smaller size of the colourless region, specifically in the ScAG/ScAGL11-silenced plants. The expression of ScCHS2, ScDFR3, and ScF3H1 increased in silenced cineraria leaves and capitulum. Furthermore, yeast two-hybrid and bimolecular fluorescence complementation experiments demonstrated that ScAG interacts with ScAGL11. Moreover, ScAG directly inhibited the transcription of ScF3H1 while ScAGL11 inhibited ScDFR3 expression by binding to their promoters separately. The findings reported herein indicate that ScAG and ScAGL11 negatively regulate anthocyanin biosynthesis in cineraria ray florets, and their differential expression in ray florets influences the bicolour pattern appearance.

10.
ACS Chem Biol ; 17(1): 39-53, 2022 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-34908399

RESUMEN

Indolmycin (IND) is a microbial natural product that selectively inhibits bacterial tryptophanyl-tRNA synthetase (TrpRS). The tryptophan biosynthesis pathway was recently shown to be an important target for developing new antibacterial agents against Mycobacterium tuberculosis (Mtb). We investigated the antibacterial activity of IND against several mycobacterial model strains. A TrpRS biochemical assay was developed to analyze a library of synthetic IND analogues. The 4″-methylated IND compound, Y-13, showed improved anti-Mtb activity with a minimum inhibitory concentration (MIC) of 1.88 µM (∼0.5 µg/mL). The MIC increased significantly when overexpression of TrpRS was induced in the genetically engineered surrogate M. bovis BCG. The cocrystal structure of Mtb TrpRS complexed with IND and ATP has revealed that the amino acid pocket is in a state between the open form of apo protein and the closed complex with the reaction intermediate. In whole-cell-based experiments, we studied the combination effect of Y-13 paired with different antibacterial agents. We evaluated the killing kinetics, the frequency of resistance to INDs, and the mode of resistance of IND-resistant mycobacteria by genome sequencing. The synergistic interaction of Y-13 with the TrpE allosteric inhibitor, indole propionic acid, suggests that prospective IND analogues could shut down tryptophan biosynthesis and protein biosynthesis in pathogens, leading to a new class of antibiotics. Finally, we discuss a strategy to expand the genome mining of antibiotic-producing microbes specifically for antimycobacterial development.


Asunto(s)
Antibacterianos/farmacología , Productos Biológicos/farmacología , Mycobacterium bovis/efectos de los fármacos , Antibacterianos/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Productos Biológicos/química , Clonación Molecular , Escherichia coli , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Genes Bacterianos , Indoles/química , Indoles/farmacología , Estructura Molecular , Mutación
11.
Plant Sci ; 313: 111094, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34763879

RESUMEN

Anthocyanins are important flavonoid pigments involved in the colouring of flowers and fruits. They are synthesized on the cytoplasmic surface of the endoplasmic reticulum and transported into the vacuole for storage. Previous reports have suggested that glutathione S-transferase (GST) is involved in anthocyanin transport. However, due to the limitation of plant materials, most GSTs only participate in the cyanidin or delphinidin transport pathway. Here, an anthocyanin-related GST, ScGST3, was identified from the transcriptome of cineraria. The expression pattern of ScGST3 was highly consistent with anthocyanin accumulation in ray florets. Molecular complementation of Arabidopsis tt19 indicated that the overexpression of ScGST3 restores the anthocyanin-deficient phenotype of the mutant. Virus-induced gene silencing (VIGS) of ScGST3 in carmine and blue cineraria leaves could inhibit anthocyanin accumulation, further confirming the function of ScGST3 in anthocyanin accumulation. In vitro assays showed that ScGST3 increases the water solubility of cyanidin-3-O-glucoside (C3G) and delphinidin-3-O-glucosid (D3G). In addition, we also identified two anthocyanin-related MYB transcription factors, ScMYB3 and ScMYB6. The expression pattern of these two genes was also highly consistent with anthocyanin accumulation. Faded abaxial leaf phenotypes were observed after the silencing of ScMYB3 and ScMYB6, and the expression levels of partial structural genes were repressed. Based on the results from dual-luciferase assays and yeast one-hybrid assays, ScMYB3 can activate the promoter of ScGST3. Collectively, the transcription of ScGST3 is regulated by ScMYB3, which plays an important role in the transport of C3G and D3G in cineraria.


Asunto(s)
Antocianinas/biosíntesis , Antocianinas/genética , Flores/metabolismo , Glutatión Transferasa/metabolismo , Pigmentación/genética , Senecio/genética , Senecio/metabolismo , Factores de Transcripción/efectos de los fármacos , China , Flores/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo , Glutatión Transferasa/genética
12.
Chem Commun (Camb) ; 57(45): 5558-5561, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-33969842

RESUMEN

Two 2-dimensional covalent organic frameworks (COFs; TJNU-203 and TJNU-204) with high crystallinity and large specific surface area are rationally fabricated using a three-connected distorted building block and linear linkers. The two COFs show high iodine uptake (5.885 g g-1 for TJNU-203 and 5.335 g g-1 for TJNU-204) on account of physical-chemical adsorption, which make them one among the best porous materials for iodine adsorption.

13.
Front Plant Sci ; 12: 640746, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33692819

RESUMEN

Polyacylated anthocyanins with multiple glycosyl and aromatic acyl groups tend to make flowers display bright and stable blue colours. However, there are few studies on the isolation and functional characterization of genes involved in the polyacylated anthocyanin biosynthesis mechanism, which limits the molecular breeding of truly blue flowers. Senecio cruentus is an important potted ornamental plant, and its blue flowers contain 3',7-polyacylated delphinidin-type anthocyanins that are not reported in any other plants, suggesting that it harbours abundant gene resources for the molecular breeding of blue flowers. In this study, using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) analysis of blue, carmine and white colours of cineraria cultivars "Venezia" (named VeB, VeC, and VeW, respectively), we found that 3',7-polyacylated anthocyanin, cinerarin, was the main pigment component that determined the blue colour of ray florets of cineraria. Based on the transcriptome sequencing and differential gene expression (DEG) analysis combined with RT- and qRT-PCR, we found two genes encoding uridine diphosphate glycosyltransferase, named ScUGT1 and ScUGT4; two genes encoding acyl-glucoside-dependent glucosyltransferases which belong to glycoside hydrolase family 1 (GH1), named ScAGGT11 and ScAGGT12; one gene encoding serine carboxypeptidase-like acyltransferase ScSCPL2; and two MYB transcriptional factor genes ScMYB2 and ScMYB4, that were specifically highly expressed in the ray florets of VeB, which indicated that these genes may be involved in cinerarin biosynthesis. The function of ScSCPL2 was analysed by virus-induced gene silencing (VIGS) in cineraria leaves combined with HPLC-MS/MS. ScSCPL2 mainly participated in the 3' and 7-position acylation of cinerarin. These results will provide new insight into the molecular basis of the polyacylated anthocyanin biosynthesis mechanism in higher plants and are of great significance for blue flower molecular breeding of ornamental plants.

14.
Chem Res Toxicol ; 34(3): 892-900, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33656867

RESUMEN

Dimethyl selenide (DMSe) is one of the major volatile organoselenium compounds released into the atmosphere through plant metabolism and microbial methylation. DMSe has been recently revealed as a precursor of secondary organic aerosol (SOA), and its resultant SOA possesses strong oxidizing capability toward thiol groups that can perturb several major biological pathways in human airway epithelial cells and is linked to genotoxicity, DNA damage, and p53-mediated stress responses. Mounting evidence has suggested that long noncoding RNAs (lncRNAs) are involved in stress responses to internal and environmental stimuli. However, the underlying molecular interactions remain to be elucidated. In this study, we performed integrative analyses of lncRNA-mRNA coexpression in the transformed human bronchial epithelial BEAS-2B cell line exposed to DMSe-derived SOA. We identified a total of 971 differentially expressed lncRNAs in BEAS-2B cells exposed to SOA derived from O3 and OH oxidation of DMSe. Gene ontology (GO) network analysis of cis-targeted genes showed significant enrichment of DNA damage, apoptosis, and p53-mediated stress response pathways. trans-Acting lncRNAs, including PINCR, PICART1, DLGAP1-AS2, and LINC01629, known to be associated with human carcinogenesis, also showed altered expression in cell treated with DMSe-SOA. Overall, this study highlights the regulatory role of lncRNAs in altered gene expression induced by DMSe-SOA exposure.


Asunto(s)
Células Epiteliales/efectos de los fármacos , Pulmón/efectos de los fármacos , Compuestos de Organoselenio/farmacología , ARN Largo no Codificante/genética , ARN Mensajero/genética , Aerosoles/farmacología , Células Cultivadas , Células Epiteliales/metabolismo , Humanos , Pulmón/metabolismo , RNA-Seq
15.
Artículo en Inglés | MEDLINE | ID: mdl-31968647

RESUMEN

We live in a rapidly changing business environment where change has become the norm for organizations to maintain competitiveness. Although both scholars and practitioners agree that organizational change communication is important to help employees adjust to change, little is known about how negative informal information before the change affects employees' reaction to the change and occurrence of possible within-person dynamics of resistance intention over time. Based on the construal-level theory, we used SPSS 22, AMOS 20, and HLM 6.0 as tools to explore how negative informal information affects individual performance. We used a multilevel approach to probe within-person processes among 215 MBA students in China. The results show that (1) negative informal information provided before the organizational change is positively related to the resistance intention, (2) resistance intention decreases significantly over time, and (3) negative informal information is negatively related to individual performance during the organizational change. The results from this study extend the literature on informal communication before the change and provide a dynamic perspective on the occurrence of possible within-person dynamics of resistance intention over time.


Asunto(s)
Comunicación , Innovación Organizacional , Adulto , China , Femenino , Humanos , Intención , Masculino , Rendimiento Laboral
16.
Polymers (Basel) ; 12(1)2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31952229

RESUMEN

Novel core-shell graphitic carbon nitride/zinc phytate (g-C3N4/PAZn) flame retardant was simple synthetized using two-dimensional g-C3N4 and bio-based PAZn by self-assembly and incorporated into epoxy resin (EP) for improving the fire safety. The flame retardance and smoke suppression were investigated by cone calorimetry. The results indicated that g-C3N4/PAZn-EP displayed outstanding flame retardancy and smoke suppression, for example, the peak heat release rate and peak smoke production rate decreased by 71.38% and 25%, respectively. Furthermore, the flame retardancy mechanism was further explored by char residue and thermal stability analysis. It can be predicted that g-C3N4/PAZn will provide valuable reference about bio-based flame retardant.

17.
Environ Sci Technol ; 53(24): 14660-14669, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31751125

RESUMEN

Dimethyl selenide (DMSe) is one of the major volatile organoselenium compounds released from aquatic and terrestrial environments through microbial transformation and plant metabolism. The detailed processes of DMSe leading to secondary organic aerosol (SOA) formation and the pulmonary health effects induced by inhalation of DMSe-derived SOA remain largely unknown. In this study, we characterized the chemical composition and formation yields of SOA produced from the oxidation of DMSe with OH radicals and O3 in controlled chamber experiments. Further, we profiled the transcriptome-wide gene expression changes in human airway epithelial cells (BEAS-2B) after exposure to DMSe-derived SOA. Our analyses indicated a significantly higher SOA yield resulting from the OH-initiated oxidation of DMSe. The oxidative potential of DMSe-derived SOA, as measured by the dithiothreitol (DTT) assay, suggested the presence of oxidizing moieties in DMSe-derived SOA at levels higher than typical ambient aerosols. Utilizing RNA sequencing (RNA-Seq) techniques, gene expression profiling followed by pathway enrichment analysis revealed several major biological pathways perturbed by DMSe-derived SOA, including elevated genotoxicity, DNA damage, and p53-mediated stress responses, as well as downregulated cholesterol biosynthesis, glycolysis, and interleukin IL-4/IL-13 signaling. This study highlights the significance of DMSe-derived SOA as a stressor in human airway epithelial cells.


Asunto(s)
Contaminantes Atmosféricos , Compuestos de Organoselenio , Aerosoles , Células Epiteliales , Humanos , Oxidación-Reducción , Transcriptoma
18.
Angew Chem Int Ed Engl ; 58(49): 17679-17683, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31583814

RESUMEN

Covalent-organic frameworks (COFs) as porous crystalline materials show promising potential applications. However, developing facile strategies for the construction of COFs directly from amorphous covalent organic polymers (COPs) is still a great challenge. To this end, we report a novel approach for easy preparation of COFs from amorphous COPs through the linkage replacement under different types of reactions. Four COFs with high crystallinity and porosity were constructed via the linkage substitution of polyimide-linked COPs to imine-linked COFs as well as imine-linked COPs to polyimide-linked COFs. The realization of the linkage substitution would significantly expand the research scope of COFs.

19.
Oncol Rep ; 41(4): 2351-2360, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30720133

RESUMEN

The development of cervical cancer (CC) is a multi­gene, multi­step carcinogenic process that involves complex genetic and epigenetic mechanisms. SRY­related HMG­box gene 11 (SOX11) is a member of the SOX family of transcription factors with an emerging crucial role in the development of various tumor types. To elucidate the function of SOX11 in cervical carcinogenesis, the expression level of SOX11 during the development of human CC was analyzed by immunohistochemistry and western blot analysis. Additionally, the methylation status of the SOX11 was examined using bisulfite sequencing and methylation­specific polymerase chain reaction. The SOX11 expression and promoter methylation in human CC cell lines were also determined. The effect of SOX11 expression restoration after 5­aza­2'­deoxycytidine (5­Aza­dC) treatment on the CC cell proliferation ability was evaluated in CC cell lines. SOX11 was highly expressed in normal cervix (NC) and precancerous low­grade squamous intraepithelial lesions, but weakly expressed or virtually absent in precancerous high­grade squamous intraepithelial lesions and CC, which is consistent with the result of the western blot analysis. Hypermethylation of the SOX11 promoter was detected in CC, which was significantly higher than that in NC samples at each CpG site. The expression level of SOX11 in the CC cell lines was downregulated compared with the positive control, Tera­1human teratoma cell line. Upon 5­Aza­dC treatment, SOX11 expression was significantly upregulated in the CC cell lines at the mRNA and protein levels, and cell proliferation was inhibited. The results indicated that the downregulation of SOX11 in CC is due to the hypermethylation of the SOX11 promoter region. Thus, SOX11 methylation may have a role in the growth of CC cells and cervical carcinogenesis.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Factores de Transcripción SOXC/genética , Proteínas Supresoras de Tumor/genética , Neoplasias del Cuello Uterino/genética , Adulto , Azacitidina/farmacología , Carcinogénesis/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Cuello del Útero/patología , Islas de CpG/genética , Metilación de ADN/efectos de los fármacos , Progresión de la Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Epigénesis Genética , Femenino , Humanos , Persona de Mediana Edad , Regiones Promotoras Genéticas/genética , Factores de Transcripción SOXC/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Neoplasias del Cuello Uterino/patología
20.
Angew Chem Int Ed Engl ; 58(15): 4906-4910, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30758117

RESUMEN

The field of covalent organic frameworks (COFs) has been developed significantly in the past decade on account of their important characteristics and vast application potential. On the other hand, the discovery of novel synthetic methodology is still a challenging task to further promote the preparation of COFs. Herein, an interesting protocol for the conversion of amorphous nonporous covalent organic polymers (COPs) to COFs was established, affording four COFs with high crystallinity and porosity. Specifically, imine-linked amorphous COP-1 was successfully converted to COF-1-4 by replacing one type of linker with other organic building blocks. The realization of this conversion provides a facile method for constructing COFs from COPs.

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