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1.
Food Chem ; 450: 139297, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38631199

RESUMO

This study aimed to investigate the antioxidative and cytoprotective activity of antioxidant peptides from fermented broad bean paste (FBBP) and explore their potential molecular mechanisms using a combined in silico and in vitro approach. Seven novel antioxidant peptides (VSRRFIYYL, SPAIPLP, PVPPPGG, KKDGYWWAKFK, LAWY, LGFMQF, and LPGCP) identified by integrated approaches of peptidomics and in silico bioinformatic analysis were synthesized, exhibiting strong antioxidant potential against in vitro radicals. Molecular docking results suggested that these peptides could form stable hydrogen bonds and solvent-accessible surface with key amino acid residues of Keap1, thus potentially regulating the Keap1-Nrf2 pathway by occupying the Nrf2-binding site on Keap1. Additionally, they exhibited strong cellular antioxidant activity and could protect HepG2 cells from AAPH-induced oxidative injury by reducing reactive oxygen species and MDA accumulation. This study firstly unraveled the molecular mechanisms of antioxidant peptides from FBBP, and provided a new theoretical basis for the high-value utilization of FBBP.

2.
J Agric Food Chem ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557018

RESUMO

In this study, in silico analysis and peptidomics were performed to examine the generation mechanism of the umami taste of fermented broad bean paste (FBBP). Based on the information from peptidomics, a total of 470 free peptides were identified from FBBP, most of which were increased after fermentation. Additionally, the increase of the content of umami peptides, organic acids, and amino acids during fermentation contributed to the perception of umami taste in FBBP. Molecule docking results inferred that these umami molecules were easy to connect with Ser, Glu, His, and Gln in the T1R3 subunit through hydrogen bonds and electrostatic interaction force. The binding sites His145, Gln389, and Glu301 particularly contributed to the formation of the ligand-receptor complexes. The aromatic interaction, hydrogen bond, hydrophilicity, and solvent-accessible surface (SAS) played key roles in the receptor-peptide interaction. Sensory evaluation and electronic tongue results showed that EDEDE, DLSESV, SNGDDE, DETL, CDLSD, and TDEE screened from FBBP had umami characteristics and umami-enhancing effects (umami threshold values ranging from 0.131 to 0.394 mmol/L). This work provides new insight into the rapid and efficient screening of novel umami peptides and a deeper understanding of the taste mechanisms of umami molecules from FBBP.

3.
Int J Biol Macromol ; : 131370, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38580027

RESUMO

Garlic essential oil (GEO) is a potential natural antioxidant and antimicrobial agent for food preservation, but its intrinsic low water-solubility, high volatility and poor stability severely limit its application and promotion. In this work, we investigated the synergistic stabilization of the GEO-in-water nanoemulsion using carboxymethyl chitosan (CCS) and Tween 80 (TW 80). Additionally, the nanoemulsion was fabricated through high-pressure microfluidization and utilized for the coating-mediated preservation of chilled pork. The garlic essential oil nanoemulsion (GEON) with 3.0 % CCS and 3.0 % TW 80 exhibited more homogeneous droplet size (around 150 nm) and narrower size distribution, while maintained long-term stability with no significant change in size during 30 d storage. Compared with free GEO, the GEONs exhibited a higher scavenging capacity to DPPH and ABTS free radicals as well as higher inhibitory effects against Escherichia coli and Staphylococcus aureus, suggesting that the encapsulation of GEO in nanoemulsion considerably improved its antioxidant and antibacterial activities. Furthermore, the results of coating preservation experiments showed that the GEON coating effectively expanded the shelf-life of chilled fresh pork for approximately one week. Altogether, this study would guide the development of GEO-loaded nanoemulsions, and promote GEON as a promising alternative for coating preservation of chilled fresh meat.

4.
Chemosphere ; 357: 142034, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615962

RESUMO

Sulfonamides, quinolones, tetracyclines, and macrolides are the most prevalent classes of antibiotics used in both medical treatment and agriculture. The misuse of antibiotics leads to their extensive dissemination in the environment. These antibiotics can modify the structure and functionality of microbial communities, consequently impacting microbial-mediated nitrogen cycling processes including nitrification, denitrification, and anammox. They can change the relative abundance of nirK/norB contributing to the emission of nitrous oxide, a potent greenhouse gas. This review provides a comprehensive examination of the presence of these four antibiotic classes across different environmental matrices and synthesizes current knowledge of their effects on the nitrogen cycle, including the underlying mechanisms. Such an overview is crucial for understanding the ecological impacts of antibiotics and for guiding future research directions. The presence of antibiotics in the environment varies widely, with significant differences in concentration and type across various settings. We conducted a comprehensive review of over 70 research articles that compare various aspects including processes, antibiotics, concentration ranges, microbial sources, experimental methods, and mechanisms of influence. Antibiotics can either inhibit, have no effect, or even stimulate nitrification, denitrification, and anammox, depending on the experimental conditions. The influence of antibiotics on the nitrogen cycle is characterized by dose-dependent responses, primarily inhibiting nitrification, denitrification, and anammox. This is achieved through alterations in microbial community composition and diversity, carbon source utilization, enzyme activities, electron transfer chain function, and the abundance of specific functional enzymes and antibiotic resistance genes. These alterations can lead to diminished removal of reactive nitrogen and heightened nitrous oxide emissions, potentially exacerbating the greenhouse effect and related environmental issues. Future research should consider diverse reaction mechanisms and expand the scope to investigate the combined effects of multiple antibiotics, as well as their interactions with heavy metals and other chemicals or organisms.

5.
Sci Total Environ ; : 172511, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641106

RESUMO

The co-occurrence of nanoplastics (NPs) and antibiotics in the environment is a growing concern for ecological safety. As NPs age in natural environments, their surface properties and morphology may change, potentially affecting their interactions with co-contaminants such as antibiotics. It is crucial to understand the effect of aging on NPs adsorption of antibiotics, but detailed studies on this topic are still scarce. The study utilized the photo-Fenton-like reaction to hasten the aging of polystyrene nanoplastics (PS-NPs). The impact of aging on the adsorption behavior of norfloxacin (NOR) was then systematically examined. The results showed a time-dependent rise in surface oxygen content and functional groups in aged PS-NPs. These modifications led to noticeable physical changes, including increased surface roughness, decreased particle size, and improved surface area. The physicochemical changes significantly increased the adsorption capacity of aged PS-NPs for norfloxacin. Aged PS-NPs showed 5.03 times higher adsorption compared to virgin PS-NPs. The adsorption mechanism analysis revealed that in addition to the electrostatic interactions, van der Waals force, hydrogen bonding, π-π* interactions and hydrophobic interactions observed with virgin PS-NPs, aged PS-NPs played a significant role in polar interactions and pore-filling mechanisms. The study highlights the potential for aging to worsen antibiotic risk in contaminated environments. This study not only enhances the comprehension of the environmental behavior of aged NPs but also provides a valuable basis for developing risk management strategies for contaminated areas.

6.
Food Microbiol ; 121: 104533, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38637092

RESUMO

Defined starter cultures, containing selected microbes could reduce the complexity of natural starter, are beneficial for controllable food fermentations. However, there are challenges in identifying key microbiota and constructing synthetic microbiota for traditional food fermentations. Here, we aimed to develop a defined starter culture for reproducible profile of flavour compounds, using Chinese Xiaoqu Baijiu fermentation as a case. We classified all microbes into 4 modules using weighted correlation network analysis. Module 3 presented significant correlations with flavour compounds (P < 0.05) and the highest gene abundance related with flavour compound production. 13 dominant species in module 3 were selected for mixed culture fermentation, and each species was individually deleted to analyse the effect on flavour compound production. Ten species, presenting significant effects (P < 0.05) on flavour compound production, were selected for developing the starter culture, including Rhizopus oryzae, Rhizopus microsporus, Saccharomyces cerevisiae, Pichia kudriavzevii, Wickerhamomyces anomalus, Lactobacillus acetotolerans, Levilactobacillus brevis, Weissella paramesenteroides, Pediococcus acidilactici, and Leuconostoc pseudomesenteroides. After optimising the structure of the starter culture, the profile similarity of flavour compounds produced by the starter culture reached 81.88% with that by the natural starter. This work indicated feasibility of reproducible profile of flavour compounds with defined starter culture for food fermentations.


Assuntos
Microbiota , Fermentação , Saccharomyces cerevisiae , China
7.
Food Chem ; 449: 139203, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38599105

RESUMO

This study examined the interaction between myofibrillar proteins (MPs) and the numbing substance hydroxy-α-sanshool (α-SOH) in a thermal environment, and provided an explanation of the numbness perception mechanism through muti-spectroscopic and molecular dynamics simulation methodology. Results showed that addition of α-SOH could reduce the particle size and molecular weight of MPs, accompanied by changes in the tertiary and secondary structure, causing the α-helix of MPs transitioned to ß-sheet and ß-turn due to the reorganization of hydrogen bonds. After a moderate heating (60 or 70 °C), MPs could form the stable complexes with α-SOH that were associated with attachment sites and protein wrapping. The thermal process might convert a portion of α-SOH' into hydroxy-ß-sanshool' (ß-SOH'). When docking with the sensory receptor TRPV1, the RMSD, RMSF and binding free energy all showed that ß-SOH' demonstrated a low affinity, thereby reducing the numbing perception. These findings can provide a theoretical foundation for the advanced processing of numbing meat products.

9.
Oncol Lett ; 27(6): 252, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38646495

RESUMO

The pan-immune-inflammation-value (PIV) is a comprehensive biomarker that integrates different peripheral blood cell subsets. The present study aimed to evaluate the prognostic ability of PIV in patients with nasopharyngeal carcinoma (NPC) undergoing chemoradiotherapy. PIV was assessed using the following equation: (Neutrophil count × platelet count × monocyte count)/lymphocyte count. The Kaplan-Meier method and Cox hazards regression models were used for survival analyses. The optimal cut-off values for PIV and systemic immune-inflammation index (SII) were determined using receiver operating characteristic analysis to be 428.0 and 1032.7, respectively. A total of 319 patients were recruited. Patients with a low baseline PIV (≤428.0) accounted for 69.9% (n=223) and patients with a high baseline PIV (>428.0) accounted for 30.1% (n=96). Compared with patients with low PIV, patients with a high PIV had significantly worse 5-year progression-free survival [PFS; 66.8 vs. 77.1%; hazard ratio (HR), 1.97; 95% confidence interval (CI), 1.22-3.23); P=0.005] and 5-year overall survival (OS; 68.7 vs. 86.9%, HR, 2.71; 95% CI, 1.45-5.03; P=0.001). PIV was also a significant independent prognostic indicator for OS (HR, 2.19; 95% CI, 1.16-4.12; P=0.016) and PFS (HR, 1.86; 95% CI, 1.14-3.04; P=0.013) and outperformed the SII in multivariate analysis. In conclusion, the PIV was a powerful predictor of survival outcomes and outperformed the SII in patients with NPC treated with chemoradiotherapy. Prospective validation of the PIV should be performed to better stratify radical treatment of patients with NPC.

10.
Oncol Lett ; 27(6): 256, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38646501

RESUMO

Cluster of differentiation 47 (CD47) is a transmembrane protein that is widely and moderately expressed on the surface of various cells and can have an essential role in mediating cell proliferation, migration, phagocytosis, apoptosis, immune homeostasis and other related responses by binding to its ligands, integrins, thrombospondin-1 and signal regulatory protein α. The poor prognosis of cancer patients is closely associated with high expression of CD47 in glioblastoma, ovarian cancer, breast cancer, bladder cancer, colon cancer and hepatocellular carcinoma. Upregulation of CD47 expression facilitates the growth of numerous types of tumor cells, while downregulation of its expression promotes phagocytosis of tumor cells by macrophages, thereby limiting tumor growth. In addition, blocking CD47 activates the cyclic GMP-AMP (cGAMP) synthase/cGAMP/interferon gene stimulating factor signaling pathway and initiates an adaptive immune response that kills tumor cells. The present review describes the structure, function and interactions of CD47 with its ligands, as well as its regulation of phagocytosis and tumor cell fate. It summarizes the therapeutics, mechanisms of action, research advances and challenges of targeting CD47. In addition, this paper provides an overview of the latest therapeutic options for targeting CD47, such as chimeric antigen receptor (CAR) T-cells, CAR macrophages and nanotechnology-based delivery systems, which are essential for future clinical research on targeting CD47.

11.
Hear Res ; 446: 109006, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38583350

RESUMO

Hair cells in the cochlear sensory epithelia serve as mechanosensory receptors, converting sound into neuronal signals. The basal sensory epithelia are responsible for transducing high-frequency sounds, while the apex handles low-frequency sounds. Age-related hearing loss predominantly affects hearing at high frequencies and is indicative of damage to the basal sensory epithelia. However, the precise mechanism underlying this site-selective injury remains unclear. In this study, we employed a microscale proteomics approach to examine and compare protein expression in different regions of the cochlear sensory epithelia (upper half and lower half) in 1.5-month-old (normal hearing) and 6-month-old (severe high-frequency hearing loss without hair cell loss) C57BL/6J mice. A total of 2,386 proteins were detected, and no significant differences in protein expression were detected in the upper half of the cochlear sensory epithelia between the two age groups. The expression of 20 proteins in the lower half of the cochlear sensory epithelia significantly differed between the two age groups (e.g., MATN1, MATN4, and AQP1). Moreover, there were 311 and 226 differentially expressed proteins between the upper and lower halves of the cochlear sensory epithelia in 1.5-month-old and 6-month-old mice, respectively. The expression levels of selected proteins were validated by Western blotting. These findings suggest that the spatial differences in protein expression within the cochlear sensory epithelia may play a role in determining the susceptibility of cells at different sites of the cochlea to age-related damage.

12.
Apoptosis ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498249

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy is highly effective for treating blood cancers such as B-cell malignancies, however, its effectiveness as an approach to treat solid tumors remains to be further explored. Here, we focused on the development of CAR-T cell therapies targeting tropomyosin-related kinase receptor B (TRKB), a highly expressed protein that is significantly associated with tumor progression, malignancy, and drug resistance in multiple forms of aggressive solid tumors. To achieve this, we screened brain-derived neurotrophic factor (BDNF) and neurotrophin 4 (NTF4) ligand-based CAR-T cells for their efficiency in targeting the TRKB receptor in the context of solid tumors, particularly hepatocellular carcinoma and pancreatic cancer. We demonstrated that TRKB is overexpressed not only in hepatocellular carcinoma and pancreatic carcinoma cell lines but also in cancer stem-like cells (CSCs). Notably, BDNF-CAR T and NTF4-CAR T cells could not only effectively target and kill TRKB-expressing pan-cancer cell lines in a dose-dependent manner but also effectively kill CSCs. We also performed in vivo studies to show that NTF4-CAR T cells have a better potential to inhibit the tumor growth of hepatocellular carcinoma xenografts in mice, compared with BDNF-CAR T cells. Taken together, our findings suggest that CAR-T targeting TRKB may be a promising approach for developing novel therapies to treat solid cancers.

13.
Insights Imaging ; 15(1): 72, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483642

RESUMO

BACKGROUND AND PURPOSE: Effective evaluation of rotator cuff tear residual tendon quality is the key to surgical repair. However, until now, the evaluation of rotator cuff tissue by ultrasonic shear wave elasticity (SWE) has been controversial. This prospective study analyzed the association between preoperative SWE and arthroscopic residual tendon quality scores. METHODS: The shear wave velocity (SWV) of the deltoid muscle, the supraspinatus tendon, and the supraspinatus muscle were measured in full-thickness rotator cuff tear patients. Tendon quality was scored according to tear size, tendon margin, tendon thickness, and footprint coverage during arthroscopy. The arthroscopic scores were used as the gold standard, and the SWV ratio of tendon and muscle (supraspinatus tendon/deltoid and supraspinatus muscle/deltoid) were calculated and correlated with the arthroscopic scores. RESULT: Eighty-nine patients (129 shoulders) were enrolled, including 89 operation shoulders and 40 control shoulders. In the group of operation shoulders, both the SWV ratios of tendon (SWV-RT) and the SWV ratio of muscle (SWV-RM) were negatively correlated with arthroscopic scores (The correlation coefficient (R) ranged from -0.722 to -0.884 and -0.569 to -0.689). The SWV-RT and SWV-RM of the operation shoulders were significantly lower than that of the control shoulders (p < 0.05). CONCLUSION: SWE could be used to predict the quality of the residual tendon before the rotator cuff repair. SWV of the supraspinatus tendon and muscle was a useful parameter to predict the quality of the residual tendon. CRITICAL RELEVANCE STATEMENT: Measuring the shear wave velocity of the supraspinatus tendon and muscle with SWE is useful for predicting the quality of the residual tendon which is one of the key factors for a successful rotator cuff repair. KEY POINTS: • Evaluating the quality of the residual tendon is important before surgery. • Elasticity measurements were negatively correlated with the arthroscopic score. • SWE is useful for predicting the quality of the residual tendon.

14.
Cell Cycle ; : 1-16, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38547309

RESUMO

MiRNAs play crucial regulatory roles in the growth and development of tumor cells by serving as carriers of post-transcriptional regulatory information derived from genes. Investigating the potential function and clinical significance of miRNA-mediated mRNA regulatory networks in liver cancer can offer novel insights and therapeutic strategies for the treatment of this disease. We identified 300 differentially expressed miRNAs, and five miRNAs were identified to be correlated with overall survival and could be used as an independent prognostic. GO enrichment analysis mainly included carboxylic acid biosynthesis, organic acid biosynthesis, peroxisomal membrane, microsomal membrane, DNA binding, C-acyltransferase activity, etc. KEGG enrichment analysis showed that the pathways of target genes related to liver cancer were mainly focused on butyric acid metabolism and partial amino acid metabolism. Eight of the top 10 HUB genes were associated with prognosis, and the expression of four genes was positively correlated with prognosis, of which ABAT, BHMT, and SHMT1 were target genes of hsa-miR-5003-3p. MiR-5003-3p inhibits ABAT/BHMT/SHMT1 expression, thereby promoting liver cancer development. Overall, our study provides new ideas for the treatment of liver cancer, and these five miRNAs may be independent prognostic biomarkers and therapeutic targets for liver cancer patients. And miR-5003-3p may be a critical factor in the mechanism of liver cancer development.

15.
Immunotherapy ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506258

RESUMO

Aim: To evaluate pembrolizumab in patients of Chinese descent with microsatellite instability-high (MSI-H)/deficient mismatch repair (dMMR) tumors enrolled in KEYNOTE-158 (Cohort L). Methods: Patients with MSI-H/dMMR advanced tumors received pembrolizumab 200 mg IV Q3W. Primary end point was overall response rate (ORR). Secondary end points were duration of response (DOR), progression-free survival (PFS) and overall survival (OS). Results: 24 patients were enrolled (20 were evaluable for efficacy). With median follow-up of 12.4 months, the ORR was 70%. DOR, PFS and OS were all not reached. A total of 19 (79%) patients had a treatment-related adverse event (AE; grade ≥3 in 4 [17%]), and 8 (33%) had an immune-mediated AE (grade ≥3 in (4 [17%]). Conclusion: Pembrolizumab provided meaningful and durable responses with manageable safety. These results are consistent with those reported for the global trial.

16.
IMA Fungus ; 15(1): 8, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38528625

RESUMO

Sarcodon and Hydnellum are two ectomycorrhizal genera of important ecological and economic value in Southwest China, and they are common in the free markets in this region. It was estimated that more than 1,500 tonnes of them were sold as edible per year, but there was little information about the taxonomic placements of these edible mushrooms sold in the markets. Traditional concepts of the two genera have also been challenged recently, and circumscription of Sarcodon and the informally defined clade "Neosarcodon" remained unresolved. In the present study, specimens collected in the field and purchased from the markets in Southwest China were analyzed based on morphological characters and DNA sequences. Phylogeny of the traditional Sarcodon s. lat. and Hydnellum s. lat. was reconstructed from the combined internal transcribed spacer (ITS), nuclear large ribosomal subunit (nLSU) and RNA polymerase II second largest subunit (RPB2) dataset based on expanded samples to reevaluate the taxonomic placements of the two genera. In the present molecular analyses, four distinct clades were recovered and strongly supported: Hydnellum, Neosarcodon, Phellodon and Sarcodon. Neosarcodon is formally introduced as a generic name to include nine species previously placed in Sarcodon, and the delimitation of Sarcodon is revised based on phylogenetic and morphological studies. Phylogenetic analyses also revealed an unexpected species diversity (17 phylogenetic species) of Sarcodon and Hydnellum in the markets; nine phylogenetic species of Sarcodon and eight of Hydnellum were uncovered from the samples collected in the markets. Eight species were resolved in the traditional S. imbricatus complex, with S. imbricatus s.str. being the most common edible stipitate hydnoid fungal species. Three of the edible Hydnellum species (H. edulium, H. subalpinum, and H. subscabrosellum), and five separated from the S. imbricatus complex (Sarcodon flavidus, S. giganteus, S. neosquamosus, S. nigrosquamosus, and S. pseudoimbricatus), are described as new. Three new Chinese records (H. illudens, H. martioflavum, and H. versipelle), and the notable S. imbricatus and S. leucopus are also reported.

17.
Adv Healthc Mater ; : e2304189, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539056

RESUMO

The systemic use of tranexamic acid (TA) as an oral drug could bring adverse reactions, while intradermal injection leads to pain and a risk of infection. Moreover, it is difficult for highly hydrophilic TA to penetrate the skin barrier that contains lots of hydrophobic lipid compounds, which poses enormous restrictions on its topical application. Current transdermal TA delivery strategies, are suffering from low drug load rates, plus its synthesis complexity, time-consumption etc., adding to the difficulty of TA topical application in clinical therapeutics. To increase the penetration of TA, a novel approach using TA-loaded ZIF-8 (TA@ZIF-8) was developed. The encapsulation efficiency of TA@ZIF-8 reached nearly 25% through physical adsorption and chemical bonding of TA indicated by theoretical simulation and the improved TA penetration was elevated through activating the aquaporin-3 (AQP-3) protein. Additionally, in vivo and in vitro experiments have demonstrated the preponderance of TA@ZIF-8 for penetration ability and the advantages in intracellular uptake, minor cytotoxicity, and inhibition of melanogenesis and inflammatory factors. Moreover, clinical trials have demonstrated the safety and efficacy of TA@ZIF-8 in the treatment of melasma and rosacea. This work presents a potential topical application of TA, free from the safety concerns associated with systemic drug administration. This article is protected by copyright. All rights reserved.

18.
ACS Nano ; 18(12): 8961-8970, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38470346

RESUMO

Valley excitons dominate the optoelectronic response of transition-metal dichalcogenides and are drastically affected by structural and environmental inhomogeneities localized in these materials. Critical to understanding and controlling these nanoscale excitonic changes is the ability to correlate the imaging of excitonic states with crystalline structures on the atomic scale. Here, we apply scanning tunneling microscope-induced luminescence microscopy to image valley excitons in a semiconducting transition-metal dichalcogenide monolayer decoupled by a 10 nanometer-thick hexagonal-boron-nitride flake incorporated in a lateral homojunction on an Au electrode surface. This design enables the observation of chiral excitonic emission arising from neutral and charged valley excitons of the monolayer semiconductor at ambipolar voltages with a quantum efficiency up to ∼10-5 photon/electron. The measured light helicity demonstrates considerable circular polarization dependent on the sample voltage, reaching as much as 40%. The real-space luminescence imaging maps─at subnanometer resolution─of the valley excitons reveal striking spatial variations associated with localized inhomogeneities, including surface impurities and possibly nanoscale dielectric and/or potential disorders in the monolayer. Our study introduces a promising format for 2D materials to explore and tailor their optoelectronic processes at the atomic scale.

19.
Exp Dermatol ; 33(3): e15048, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38439204

RESUMO

As the largest organ, the skin provides the first line of defence against environmental pollutants. Different pollutants have varied damage to the skin due to their own physical-chemical properties. A previous epidemiological study by our team revealed that eczema was positively correlated with different air pollutants. However, the mechanism of action from different pollutants on the skin is less known. In this work, the differences among the genotoxicity, intracellular reactive oxygen species, and barrier-related parameters caused by two kinds of air pollutants, that is, S1650b and carbon black (CB) were investigated by Western blot, TUNEL, comet assay and RNA-sequences. The results indicated that both S1650b and CB caused DNA damage of keratinocytes. With the content of lipophilic polycyclic aromatic hydrocarbons (PAH), S1650b leaked into the keratinocytes easily, which activated the aromatic hydrocarbon receptor (AhR) in keratinocytes, leading to worse damage to barrier-related proteins than CB. And CB-induced higher intracellular ROS than S1650b due to the smaller size which make it enter the keratinocytes easier. RNA-sequencing results revealed that S1650b and CB both caused DNA damage of keratinocytes, and the intervention of S1650b significantly upregulated AhR, cytochrome oxidase A1 and B1 (CYP1A1 and CYP1B1) genes, while the results showed oppositely after CB intervention. The mechanism of keratinocyte damage caused by different air particle pollutants in this study will help to expand our understanding on the air pollutant-associated skin disease at cell levels.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Fuligem , Material Particulado/toxicidade , Queratinócitos , Dano ao DNA , Estresse Oxidativo , Poluentes Atmosféricos/toxicidade , RNA
20.
Mod Rheumatol ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441253

RESUMO

BACKGROUND: Osteoarthritis (OA) is the most common chronic joint degenerative disease. Mitophagy is closely related to OA pathogenesis. Herein, we investigated the role of lncRNA OIP5-AS1 in regulating mitophagy during OA. METHODS: RT-qPCR and Western blotting were utilized to analyze gene and protein levels. RIP and RNA pull down verified the relationship between OIP5-AS1, FUS and PPAR-γ. CCK-8 assay detected cells viability. ELISA evaluated the secretion of inflammatory cytokines. Flow cytometry measured the contents of ROS and Ca2+. Immunofluorescence staining analyzed TOMM20 and LC3B levels. JC-1 staining was adopted to measure mitochondrial membrane potential. The changes of mitophagy were analyzed by TEM. RESULTS: LPS treatment contributed to the decrease of chondrocytes viability, calcium level and inhibited mitochondrial membrane potential, while elevated the secretion of inflammatory factors, ROS accumulation and TOMM20 expression. Additionally, LPS decreased the ratio of LC3II/I, Parkin and PINK1 protein levels, and increased p62 and TOMM20 protein levels. Furthermore, overexpression of OIP5-AS1 inhibited LPS-induced chondrocytes injury and activated mitophagy. OIP5-AS1 upregulated PPAR-γ mRNA level to regulate AMPK/Akt/mTOR signaling by interacting with FUS. In addition, PPAR-γ overexpression alleviated LPS induced chondrocytes injury by activating AMPK/Akt/mTOR signaling. Knockdown of PPAR-γ reversed the promotion of OIP5-AS1 upregulation on mitophagy. CONCLUSION: OIP5-AS1 promotes PPAR-γ expression to activate the AMPK/Akt/mTOR signaling, thereby enhancing mitophagy and alleviating OA progression. It is suggested that OIP5-AS1 may function as a protector in OA development.

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