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1.
Nat Commun ; 15(1): 5024, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38866773

RESUMEN

Chemical etching of nano-sized metal clusters at the atomic level has a high potential for creating metal number-specific structures and functions that are difficult to achieve with bottom-up synthesis methods. In particular, precisely etching metal atoms one by one from nonmetallic element-centred metal clusters and elucidating the relationship between their well-defined structures, and chemical and physical properties will facilitate future materials design for metal clusters. Here we report the single-gold etching at a hypercarbon centre in gold(I) clusters. Specifically, C-centred hexagold(I) clusters protected by chiral N-heterocyclic carbenes are etched with bisphosphine to yield C-centred pentagold(I) (CAuI5) clusters. The CAuI5 clusters exhibit an unusually large bathochromic shift in luminescence, which is reproduced theoretically. The etching mechanism is experimentally and theoretically suggested to be a tandem dissociation-association-elimination pathway. Furthermore, the vacant site of the central carbon of the CAuI5 cluster can accommodate AuCl, allowing for post-functionalisation of the C-centred gold(I) clusters.

2.
STAR Protoc ; 5(2): 103120, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38857154

RESUMEN

The model of M2-like tumor-associated macrophages (TAMs) is an increasingly attractive model for the study of TAMs. However, the detailed process of M2-like TAMs polarization induced by lactic acid or conditioned medium from Lewis cells (LCM) and the identification of M2-like TAMs is not yet available. In this protocol, we present the detailed methods to induce M2-like TAMs polarization and verify its functionality in order to better carry out related research. For complete details on the use and execution of this protocol, please refer to Fang et al.1.


Asunto(s)
Ácido Láctico , Macrófagos Asociados a Tumores , Medios de Cultivo Condicionados/farmacología , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/efectos de los fármacos , Ácido Láctico/metabolismo , Ácido Láctico/farmacología , Animales , Ratones , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Modelos Biológicos
3.
Nano Lett ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38836517

RESUMEN

As a potential alternative to antibiotics, hyperbranched poly(ionic liquid)s (HPILs) have demonstrated significant potential in combating bacterial biofilms. However, their high cation density poses a high risk of toxicity, greatly limiting their in vivo applications. In this study, we constructed a biocompatible HPIL (HPIL-Glu) from a hyperbranched polyurea core with modified terminals featuring charge-convertible ionic liquids. These ionic liquid moieties consist of an ammonium-based cation and a gluconate (Glu) organic counter. HPIL-Glu could form a homogeneous nanoassembly in water and exhibited a pH-responsive charge conversion property. Under neutral conditions, Glu shielded the positively charged surface, minimizing the toxicity. In a mildly acidic environment, Glu protonation exposes cationic moieties to biofilm eradication. Comprehensive antimicrobial assessments demonstrate that HPIL-Glu effectively kills bacteria and promotes the healing of bacteria-infected chronic wounds. Furthermore, prolonged exposure to HPIL-Glu does not induce antimicrobial resistance.

4.
Angew Chem Int Ed Engl ; : e202409020, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899789

RESUMEN

The strategy of integrating conformational isomerization donors and chiral acceptor in single molecule was proposed to construct white circularly polarized luminescence (WCPL) materials in this work. Consequently, a pair of dual-emission enantiomers, namely (R/S)-DO-PTZ, were designed and synthesized, which displayed white emission with blue and yellow dual-emission bands in solution and solid films at Commission Internationale de l'Eclairage (CIE) coordinates of (0.30, 0.33) and (0.33, 0.35), respectively. Meanwhile, (R/S)-DO-PTZ exhibited high PLQY of up to 67% in doped films and obvious mirror-image WCPL signals with |glum| value of 3.0 × 10-3. Moreover, white circularly polarized electroluminescence (WCPEL) based on organic light-emitting diodes (OLEDs) with (R/S)-DO-PTZ as emitters were also achieved with CIE coordinates of (0.32, 0.37) and EQEmax of 4.7%, representing the state-of-the-art level of white OLEDs based on single-molecule purely organic emitters. By optimizing the device structure, warm WCPEL devices were further obtained with |gEL| value of 2.8 × 10-3, CIE coordinates of (0.37, 0.48) and EQEmax of up to 15.6%. To our knowledge, this is the first report of CP-WOLEDs based on single-molecule purely organic emitters.

5.
Chin J Integr Med ; 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38907069

RESUMEN

OBJECTIVE: To confirm the efficacy and safety of Ganyushu Granule (GYSG) in treating premenstrual syndrome (PMS) in patients with Gan (Liver) depression and qi stagnation syndrome (GDQSS) and determine its effective dosage. METHODS: From June 2018 to March 2021, a total of 240 PMS women with GDQSS were included and randomly divided into 3 groups in a 1:1:1 ratio using central block randomization: high-dose GYSG group (n=78, GYSG 2 packs/time), low-dose GYSG group (n=82, GYSG and its simulant 1 pack/time), and placebo group (n=80, GYSG simulant 2 packs/time). Treatment with GYSG or placebo was given thrice daily and for up to 3 menstrual cycles. Primary outcomes were PMS diary (PMSD) score and premenstrual tension syndrome self-rating scale (PMTS). Secondary outcomes were Chinese medicine (CM) syndrome efficacy. PMSD, PMTS, and efficacy of CM were evaluated with menstrual cycles during the treatment period. Outcome indicators were analyzed after each menstrual cycle. All analyses were performed using an intention-to-treat method, and clinical safety was assessed. RESULTS: Of the 216 patients included in the effectiveness analysis, 70, 75, and 71 patients were in the high-, low-dose GYSG, and placebo groups, respectively. From the 2nd treatment cycle, the change in PMSD scores in the high- and low-dose groups was lower than that in the placebo group (P<0.05). PMTS scores in the high-dose GYSG group after the 1st treatment cycle was lower than that in the placebo group (P<0.05), while after the 3rd treatment cycle, that in the low-dose group was lower than that in the placebo group (P<0.05). After the 2nd treatment cycle, the high-dose GYSG group had the best CM syndrome efficacy (P<0.05). No serious adverse reactions were reported. CONCLUSIONS: GYSG was safe and well-tolerated at both doses for treating PMS patients with GDQSS. High-dose GYSG might be the optimal dose for a phase III trial. (Registration No. ChiCTR1800016595).

6.
Int J Ophthalmol ; 17(3): 420-434, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721513

RESUMEN

AIM: To explore whether autophagy functions as a cellular adaptation mechanism in lens epithelial cells (LECs) under hyperosmotic stress. METHODS: LECs were treated with hyperosmotic stress at the concentration of 270, 300, 400, 500, or 600 mOsm for 6, 12, 18, 24h in vitro. Polymerase chain reaction (PCR) was employed for the mRNA expression of autophagy-related genes, while Western blotting detected the targeted protein expression. The transfection of stub-RFP-sens-GFP-LC3 autophagy-related double fluorescence lentivirus was conducted to detect the level of autophagy flux. Scanning electron microscopy was used to detect the existence of autolysosome. Short interfering RNA of autophagy-related gene (ATG) 7, transient receptor potential vanilloid (TRPV) 1 overexpression plasmid, related agonists and inhibitors were employed to their influence on autophagy related pathway. Flow cytometry was employed to test the apoptosis and intracellular Ca2+ level. Mitochondrial membrane potential was measured by JC-1 staining. The cell counting kit-8 assay was used to calculate the cellular viability. The wound healing assay was used to evaluate the wound closure rate. GraphPad 6.0 software was utilized to evaluate the data. RESULTS: The hyperosmotic stress activated autophagy in a pressure- and time-dependent manner in LECs. Beclin 1 protein expression and conversion of LC3B II to LC3B I increased, whereas sequestosome-1 (SQSTM1) protein expression decreased. Transient Ca2+ influx was stimulated caused by hyperosmotic stress, levels of mammalian target of rapamycin (mTOR) phosphorylation decreased, and the level of AMP-activated protein kinase (AMPK) phosphorylation increased in the early stage. Based on this evidence, autophagy activation through the Ca2+-dependent AMPK/mTOR pathway might represent an adaptation process in LECs under hyperosmotic stress. Hyperosmotic stress decreased cellular viability and accelerated apoptosis in LECs and cellular migration decreased. Inhibition of autophagy by ATG7 knockdown had similar results. TRPV1 overexpression increased autophagy and might be crucial in the occurrence of autophagy promoted by hyperosmotic stress. CONCLUSION: A combination of hyperosmotic stress and autophagy inhibition may be a promising approach to decrease the number of LECs in the capsular bag and pave the way for improving prevention of posterior capsular opacification and capsular fibrosis.

7.
Chemistry ; : e202401094, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38797717

RESUMEN

A 'passivated precursor' approach is developed for the efficient synthesis and isolation of all-alkynyl-protected gold nanoclusters. Direct reduction of dpa-passivated precursor Au-dpa (Hdpa = 2,2'-dipyridylamine) in one-pot under ambient conditions gives a series of clusters including Au22(C≡CR)18 (R = -C6H4-2-F), Au36(C≡CR)24, Au44(C≡CR)28, Au130(C≡CR)50, and Au144(C≡CR)60. These clusters can be well separated via column chromatography. The overall isolation yield of this series of clusters is 40% (based on gold), which is much improved in comparison with previous approaches. It is notable that the molecular structure of the giant cluster Au130(C≡CR)50 is revealed, which presents important information for understanding the structure of the mysterious Au130 nanoclusters. Theoretical calculations indicated Au130(C≡CR)50 has a smaller HOMO-LUMO gap than Au130(S-C6H4-4-CH3)50. This facile and reliable synthetic approach will greatly accelerate further studies on all-alkynyl-protected gold nanoclusters.

8.
J Nanobiotechnology ; 22(1): 275, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778401

RESUMEN

BACKGROUND: Acute gouty is caused by the excessive accumulation of Monosodium Urate (MSU) crystals within various parts of the body, which leads to a deterioration of the local microenvironment. This degradation is marked by elevated levels of uric acid (UA), increased reactive oxygen species (ROS) production, hypoxic conditions, an upsurge in pro-inflammatory mediators, and mitochondrial dysfunction. RESULTS: In this study, we developed a multifunctional nanoparticle of polydopamine-platinum (PDA@Pt) to combat acute gout by leveraging mild hyperthermia to synergistically enhance UA degradation and anti-inflammatory effect. Herein, PDA acts as a foundational template that facilitates the growth of a Pt shell on the surface of its nanospheres, leading to the formation of the PDA@Pt nanomedicine. Within this therapeutic agent, the Pt nanoparticle catalyzes the decomposition of UA and actively breaks down endogenous hydrogen peroxide (H2O2) to produce O2, which helps to alleviate hypoxic conditions. Concurrently, the PDA component possesses exceptional capacity for ROS scavenging. Most significantly, Both PDA and Pt shell exhibit absorption in the Near-Infrared-II (NIR-II) region, which not only endow PDA@Pt with superior photothermal conversion efficiency for effective photothermal therapy (PTT) but also substantially enhances the nanomedicine's capacity for UA degradation, O2 production and ROS scavenging enzymatic activities. This photothermally-enhanced approach effectively facilitates the repair of mitochondrial damage and downregulates the NF-κB signaling pathway to inhibit the expression of pro-inflammatory cytokines. CONCLUSIONS: The multifunctional nanomedicine PDA@Pt exhibits exceptional efficacy in UA reduction and anti-inflammatory effects, presenting a promising potential therapeutic strategy for the management of acute gout.


Asunto(s)
Gota , Indoles , Polímeros , Especies Reactivas de Oxígeno , Ácido Úrico , Gota/tratamiento farmacológico , Gota/metabolismo , Gota/terapia , Especies Reactivas de Oxígeno/metabolismo , Animales , Ratones , Polímeros/química , Indoles/química , Indoles/farmacología , Nanopartículas/química , Platino (Metal)/química , Platino (Metal)/farmacología , Platino (Metal)/uso terapéutico , Humanos , Peróxido de Hidrógeno/metabolismo , Hipertermia Inducida/métodos , Células RAW 264.7 , Terapia Fototérmica/métodos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Masculino
9.
Pharm Biol ; 62(1): 456-471, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38773737

RESUMEN

CONTEXT: The mechanisms of Traditional Chinese Medicine (TCM) Guizhi-Gancao Decoction (GGD) remain unknown. OBJECTIVE: This study explores the mechanisms of GGD against cardiac hypertrophy. MATERIALS AND METHODS: Network pharmacology analysis was carried out to identify the potential targets of GGD. In vivo experiments, C57BL/6J mice were divided into Con, phenylephrine (PE, 10 mg/kg/d), 2-chloroadenosine (CADO, the stable analogue of adenosine, 2 mg/kg/d), GGD (5.4 g/kg/d) and GGD (5.4 g/kg/d) + CGS15943 (a nonselective adenosine receptor antagonist, 4 mg/kg/d). In vitro experiments, primary neonatal rat cardiomyocytes (NRCM) were divided into Con, PE (100 µM), CADO (5 µM), GGD (10-5 g/mL) and GGD (10-5 g/mL) + CGS15943 (5 µM). Ultrasound, H&E and Masson staining, hypertrophic genes expression and cell surface area were conducted to verify the GGD efficacy. Adenosine receptors (ADORs) expression were tested via real-time polymerase chain reaction (PCR), western blotting and immunofluorescence analysis. RESULTS: Network pharmacology identified ADORs among those of the core targets of GGD. In vitro experiments demonstrated that GGD attenuated PE-induced increased surface area (with an EC50 of 5.484 × 10-6 g/mL). In vivo data shown that GGD attenuated PE-induced ventricular wall thickening. In vitro and in vivo data indicated that GGD alleviated PE-induced hypertrophic gene expression (e.g., ANP, BNP and MYH7/MYH6), A1AR over-expression and A2aAR down-expression. Moreover, CADO exerts effects similar to GGD, whereas CGS15943 eliminated most effects of GGD. DISCUSSION AND CONCLUSIONS: Our findings suggest the mechanism by which GGD inhibits cardiac hypertrophy, highlighting regulation of ADORs as a potential therapeutic strategy for HF.


Asunto(s)
Cardiomegalia , Medicamentos Herbarios Chinos , Ratones Endogámicos C57BL , Miocitos Cardíacos , Farmacología en Red , Fenilefrina , Animales , Medicamentos Herbarios Chinos/farmacología , Fenilefrina/farmacología , Cardiomegalia/tratamiento farmacológico , Cardiomegalia/inducido químicamente , Ratones , Masculino , Ratas , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Miocitos Cardíacos/metabolismo , Ratas Sprague-Dawley , Células Cultivadas , Modelos Animales de Enfermedad , Medicina Tradicional China/métodos
10.
Nutrients ; 16(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38732552

RESUMEN

Ulcerative colitis (UC) is a chronic intestinal ailment which cannot be completely cured. The occurrence of UC has been on the rise in recent years, which is highly detrimental to patients. The effectiveness of conventional drug treatment is limited. The long-term usage of these agents can lead to substantial adverse effects. Therefore, the development of a safe and efficient dietary supplement is important for the prevention of UC. Echinacea purpurea polysaccharide (EPP) is one of the main bioactive substances in Echinacea purpurea. EPP has many favorable effects, such as antioxidative, anti-inflammatory, and antitumor effects. However, whether EPP can prevent or alleviate UC is still unclear. This study aims to analyze the effect and mechanism of EPP on UC in mice using a 3% dextran sulfate sodium (DSS)-induced UC model. The results showed that dietary supplementation with 200 mg/kg EPP significantly alleviated the shortening of colon length, weight loss, and histopathological damage in DSS-induced colitis mice. Mechanistically, EPP significantly inhibits the activation of the TLR4/NF-κB pathway and preserves the intestinal mechanical barrier integrity by enhancing the expression of claudin-1, ZO-1, and occludin and reducing the loss of goblet cells. Additionally, 16S rRNA sequencing revealed that EPP intervention reduced the abundance of Bacteroides, Escherichia-Shigella, and Klebsiella; the abundance of Lactobacillus increased. The results of nontargeted metabonomics showed that EPP reshaped metabolism. In this study, we clarified the effect of EPP on UC, revealed the potential function of EPP, and supported the use of polysaccharide dietary supplements for UC prevention.


Asunto(s)
Colitis Ulcerosa , Sulfato de Dextran , Echinacea , Microbioma Gastrointestinal , FN-kappa B , Polisacáridos , Receptor Toll-Like 4 , Animales , Masculino , Ratones , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/microbiología , Colon/efectos de los fármacos , Colon/patología , Colon/metabolismo , Suplementos Dietéticos , Modelos Animales de Enfermedad , Echinacea/química , Microbioma Gastrointestinal/efectos de los fármacos , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Polisacáridos/farmacología , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 4/metabolismo
11.
Food Chem ; 453: 139680, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-38788648

RESUMEN

Hydrophobic coatings have wide applications, but face challenges in food flexible packaging in terms of poor adhesion and inadequate wear resistance. Health hazards and poor adhesion drive the search for novel hydrophobic coatings substitutes. Here, we introduced rationally synthesized carnauba wax-SiO2 microspheres as a component to composite polyethylene (PE) film construction, and created a wear-resistant hydrophobic composite PE film via the blown film technique. The resultant hydrophobic composite film demonstrated an enhanced water contact angle from 86° to above 100°, coupled with favorable mechanical properties such as wear resistance, tensile strength and effective barrier performance against water vapor and oxygen. Upon implementation in the preservation of a Cantonese delicacy, Chaoshan fried shrimp rolls, it was observed that at 25 °C, the carnauba wax-SiO2-PE composite packaging film extended the shelf life of the product by 3 days compared to pure PE film.


Asunto(s)
Embalaje de Alimentos , Conservación de Alimentos , Interacciones Hidrofóbicas e Hidrofílicas , Polietileno , Ceras , Polietileno/química , Embalaje de Alimentos/instrumentación , Animales , Ceras/química , Conservación de Alimentos/métodos , Conservación de Alimentos/instrumentación , Resistencia a la Tracción , Dióxido de Silicio/química , Penaeidae/química
12.
Food Funct ; 15(10): 5466-5484, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38690672

RESUMEN

Inflammatory bowel disease (IBD) is difficult to cure, and formulating a dietary plan is an effective means to prevent and treat this disease. Wheat peptide contains a variety of bioactive peptides with anti-inflammatory and antioxidant functions. The results of this study showed that preventive supplementation with wheat peptide (WP) can significantly alleviate the symptoms of dextran sulfate sodium (DSS)-induced colitis in mice. WP can increase body weight, alleviate colon shortening, and reduce disease activity index (DAI) scores. In addition, WP improved intestinal microbial disorders in mice with colitis. Based on LC-MS, a total of 313 peptides were identified in WP, 4 of which were predicted to be bioactive peptides. The regulatory effects of WP and four bioactive peptides on the Keap1-Nrf2 signaling pathway were verified in Caco-2 cells. In conclusion, this study demonstrated that WP alleviates DSS-induced colitis by helping maintain gut barrier integrity and targeting the Keap1-Nrf2 axis; these results provided a rationale for adding WP to dietary strategies to prevent IBD.


Asunto(s)
Colitis , Sulfato de Dextran , Proteína 1 Asociada A ECH Tipo Kelch , Ratones Endogámicos C57BL , Factor 2 Relacionado con NF-E2 , Péptidos , Transducción de Señal , Triticum , Animales , Factor 2 Relacionado con NF-E2/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Ratones , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Sulfato de Dextran/efectos adversos , Transducción de Señal/efectos de los fármacos , Humanos , Triticum/química , Células CACO-2 , Péptidos/farmacología , Masculino , Modelos Animales de Enfermedad , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efectos de los fármacos
13.
World J Hepatol ; 16(5): 800-808, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38818290

RESUMEN

BACKGROUND: In recent years, approximately half of the newly diagnosed cases and mortalities attributed to hepatocellular carcinoma (HCC) have been reported in China. Despite the high incidence of HCC, there remains a paucity of data regarding the natural growth pattern and the determination of optimal surveillance intervals specific to the Chinese population. AIM: To quantify the natural tumor growth pattern of HCC in regional China. METHODS: A retrospective analysis was performed on patients from a single institution in Southwest China who had undergone two or more serial dynamic computed tomography or magnetic resonance imaging scans between 2014 and 2020, without having received any anti-cancer therapy. Tumor growth was assessed using tumor volume doubling time (TVDT) and tumor growth rate (TGR), with volumes measured manually by experienced radiologists. Simple univariate linear regression and descriptive analysis were applied to explore associations between growth rates and clinical factors. RESULTS: This study identifies the median TVDT for HCC as 163.4 d, interquartile range (IQR) 72.1 to 302.3 d, with a daily TGR of 0.42% (IQR 0.206%-0.97%). HCC growth patterns reveal that about one-third of tumors grow indolently with TVDT exceeding 270 d, another one-third of tumors exhibit rapid growth with TVDT under 90 d, and the remaining tumors show intermediate growth rates, with TVDT ranging between 3 to 9 months. CONCLUSION: The identified TGRs support biannual surveillance and follow-up for HCC patients in certain regions of China. Given the observed heterogeneity in HCC growth, further investigation is warranted.

14.
Heliyon ; 10(7): e28531, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38586380

RESUMEN

Improvement of sugarcane is hampered due to its narrow genetic base, and the difficulty in synchronizing flowering further hinders the exploitation of the genetic potential of available germplasm resources. Therefore, the continuous evaluation and optimization of flowering control and induction techniques are vital for sugarcane improvement. In view of this, the review was conducted to investigate the current understanding of photoperiodic and lighting treatment effects on sugarcane flowering and its genetic regulation. Photoperiod facilities have made a significant contribution to flowering control in sugarcane; however, inductive photoperiods are still unknown for some genotypes, and some intended crosses are still impossible to produce because of unresponsive varieties. The effectiveness of lower red/far-red ratios in promoting sugarcane flowering has been widely understood. Furthermore, there is vast potential for utilizing blue, red, and far-red light wavelengths in the flowering control of sugarcane. In this context, light-emitting diodes (LEDs) remain efficient sources of light. Therefore, the combined use of photoperiod regimes with different light wavelengths and optimization of such treatment combinations might help to control and induce flowering in sugarcane parental clones. In sugarcane, FLOWERING LOCUS T (ScFT) orthologues from ScFT1 to ScFT13 have been identified, and interestingly, ScFT3 has evidently been identified as a floral inducer in sugarcane. However, independent assessments of different FT-like gene family members are recommended to comprehensively understand their role in the regulation of flowering. Similarly, we believe this review provides substantial information that is vital for the manipulation of flowering and exploitation of germplasm resources in sugarcane breeding.

15.
Nat Commun ; 15(1): 3299, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38632245

RESUMEN

Improving the absorption of electromagnetic waves at low-frequency bands (2-8 GHz) is crucial for the increasing electromagnetic (EM) pollution brought about by the innovation of the fifth generation (5G) communication technology. However, the poor impedance matching and intrinsic attenuation of material in low-frequency bands hinders the development of low-frequency electromagnetic wave absorbing (EMWA) materials. Here we propose an interface-induced dual-pinning mechanism and establish a magnetoelectric bias interface by constructing bilayer core-shell structures of NiFe2O4 (NFO)@BiFeO3 (BFO)@polypyrrole (PPy). Such heterogeneous interface could induce distinct magnetic pinning of the magnetic moment in the ferromagnetic NFO and dielectric pinning of the dipole rotation in PPy. The establishment of the dual-pinning effect resulted in optimized impedance and enhanced attenuation at low-frequency bands, leading to better EMWA performance. The minimum reflection loss (RLmin) at thickness of 4.43 mm reaches -65.30 dB (the optimal absorption efficiency of 99.99997%), and the effective absorption bandwidth (EAB) can almost cover C-band (4.72 ~ 7.04 GHz) with low filling of 15.0 wt.%. This work proposes a mechanism to optimize low-frequency impedance matching with electromagnetic wave (EMW) loss and pave an avenue for the research of high-performance low-frequency absorbers.

16.
Artículo en Inglés | MEDLINE | ID: mdl-38659261

RESUMEN

BACKGROUND: Honokiol is a natural polyphenolic compound extracted from Magnolia officinali, which is commonly used material in Chinese herbal medicine, has a variety of biological functions, including anti-tumor, anti-oxidant, anti-inflammation, anti-microbial and anti-allergy. Although honokiol has numerous beneficial effects on human diseases, the underlying mechanisms of tumor metastasis are still unclear. Previously, we reported that honokiol suppresses thyroid cancer cell proliferation with cytotoxicity through cell cycle arrest, apoptosis, and dysregulation of intracellular hemostasis. Herein, we hypothesized that the antioxidant effect of honokiol might play a critical role in thyroid cancer cell proliferation and migration. METHODS: The cell viability assays, cellular reactive oxygen species (ROS) activity, cell migration, and immunoblotting were performed after cells were treated with honokiol. RESULTS: Based on this hypothesis, we first demonstrated that honokiol suppresses cell proliferation in two human anaplastic thyroid carcinoma (ATC) cell lines, KMH-2 and ASH-3, within a dosage- and time-dependent manner by cell counting kit-8 (CCK-8) assay. Next, we examined that honokiol induced ROS activation and could be suppressed by pre-treated with an antioxidant agent, N-acetyl-l-cysteine (NAC). Furthermore, the honokiol suppressed cell proliferation can be rescued by pre-treated with NAC. Finally, we demonstrated that honokiol inhibited ATC cell migration by modulating epithelial-mesenchymal transition (EMT)-related markers by Western blotting. CONCLUSION: Taken together, we provided the potential mechanism for treating ATC cells with honokiol, which significantly suppresses tumor proliferation and inhibits tumor metastasis in vitro through reactive oxygen species (ROS) induction.

17.
Environ Sci Technol ; 58(18): 7968-7976, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38680115

RESUMEN

Nitrogen oxide (NOx) emissions from heavy-duty diesel vehicles (HDDVs) have adverse effects on human health and the environment. On-board monitoring (OBM), which can continuously collect vehicle performance and NOx emissions throughout the operation lifespan, is recognized as the core technology for future vehicle in-use compliance, but its large-scale application has not been reported. Here, we utilized OBM data from 22,520 HDDVs in China to evaluate their real-world NOx emissions. Our findings showed that China VI HDDVs had a 73% NOx emission reduction compared with China V vehicles, but a considerable proportion still faced a significant risk of higher NOx emissions than the corresponding limits. The unsatisfactory efficiency of the emission treatment system under disadvantageous driving conditions (e.g., low speed or ambient temperature) resulted in the incompliance of NOx emissions, especially for utility vehicles (sanitation/garbage trucks). Furthermore, the observed intertrip and seasonal variability of NOx emissions demonstrated the need for a long-term continuous monitoring protocol instead of instantaneous evaluation for the OBM. With both functions of emission monitoring and malfunction diagnostics, OBM has the potential to accurately verify the in-use compliance status of large-scale HDDVs and discern the responsibility of high-emitting activities from manufacturers, vehicle operators, and driving conditions.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Óxidos de Nitrógeno , Emisiones de Vehículos , Emisiones de Vehículos/análisis , Monitoreo del Ambiente/métodos , Óxidos de Nitrógeno/análisis , Contaminantes Atmosféricos/análisis , China
18.
Eur J Pharmacol ; 973: 176585, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38636799

RESUMEN

This study aimed to explore the effects and mechanism of action of stachydrine hydrochloride (Sta) against myocardial infarction (MI) through sarcoplasmic/endoplasmic reticulum stress-related injury. The targets of Sta against MI were screened using network pharmacology. C57BL/6 J mice after MI were treated with saline, Sta (6 or 12 mg kg-1) for 2 weeks, and adult mouse and neonatal rat cardiomyocytes (AMCMs and NRCMs) were incubated with Sta (10-4-10-6 M) under normoxia or hypoxia for 2 or 12 h, respectively. Echocardiography, Evans blue, and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used for morphological and functional analyses. Endoplasmic reticulum stress (ERS), unfolded protein reaction (UPR), apoptosis signals, cardiomyocyte contraction, and Ca2+ flux were detected using transmission electron microscopy (TEM), western blotting, immunofluorescence, and sarcomere and Fluo-4 tracing. The ingredient-disease-pathway-target network revealed targets of Sta against MI were related to apoptosis, Ca2+ homeostasis and ERS. Both dosages of Sta improved heart function, decreased infarction size, and potentially increased the survival rate. Sta directly alleviated ERS and UPR and elicited less apoptosis in the border myocardium and hypoxic NRCMs. Furthermore, Sta upregulated sarcoplasmic reticulum Ca2+-ATPase 2a (SERCA2a) in both ischaemic hearts and hypoxic NRCMs, accompanied by restored sarcomere shortening, resting intracellular Ca2+, and Ca2+ reuptake time constants (Tau) in Sta-treated hypoxic ARCMs. However, 2,5-di-t-butyl-1,4-benzohydroquinone (BHQ) (25 µM), a specific SERCA inhibitor, totally abolished the beneficial effect of Sta in hypoxic cardiomyocytes. Sta protects the heart from MI by upregulating SERCA2a to maintain intracellular Ca2+ homeostasis, thus alleviating ERS-induced apoptosis.


Asunto(s)
Apoptosis , Calcio , Estrés del Retículo Endoplásmico , Homeostasis , Ratones Endogámicos C57BL , Miocitos Cardíacos , Prolina/análogos & derivados , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico , Animales , Estrés del Retículo Endoplásmico/efectos de los fármacos , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Calcio/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Homeostasis/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ratones , Masculino , Cardiotónicos/farmacología , Cardiotónicos/uso terapéutico , Ratas , Infarto del Miocardio/patología , Infarto del Miocardio/metabolismo , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/prevención & control , Bencilisoquinolinas/farmacología , Bencilisoquinolinas/uso terapéutico , Respuesta de Proteína Desplegada/efectos de los fármacos
19.
Foods ; 13(8)2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38672918

RESUMEN

A reliable strategy for improving the stability and shelf life of protein-stabilized systems is by covalently attaching the protein onto a polysaccharide. In this study, ovalbumin (OVA) was modified with dextran (DEX) of different molecular weights by the Maillard reaction, and was used to enhance the stability of emulsions loaded with resveratrol. The surface hydrophobicity, thermal stability, and FT-IR spectroscopy of the OVA-DEX conjugates were evaluated. The results showed that the surface hydrophobicity of OVA decreased, while the thermal stability of OVA was significantly improved after DEX covalent modification. The OVA-DEX1k-stabilized emulsion exhibited high encapsulation efficiency of resveratrol, with the value of 89.0%. In addition, OVA-DEX was considerably more effective in droplet stabilization against different environmental stresses (heat, pH, and ionic strength). After 28 days of storage at 25 °C, the OVA-stabilized emulsion showed faster decomposition of resveratrol, whereas the OVA-DEX-conjugate-stabilized emulsion had approximately 73% retention of resveratrol. Moreover, the antioxidant activity of resveratrol-loaded emulsions stabilized by OVA-DEX was higher during storage under different temperatures. These results proved that the OVA-DEX conjugates had the potential to form stable, food-grade emulsion-based delivery systems against environmental stresses, which strongly supports their potential in the field of food and biomedical applications.

20.
Macromol Rapid Commun ; : e2400108, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639216

RESUMEN

Various acoustic materials are developed to resolve noise pollution problem in many industries. Especially, materials with porous structure are broadly used to absorb sound energy in civil construction and transportation area. Polyurethane (PU) porous materials possess excellent damping properties, good toughness, and well-developed pore structures, which have a broad application prospect in sound absorption field. This work aims to summarize the recent progress of fabrication and structure for PU porous materials in sound absorption application. The sound absorption mechanisms of porous materials are introduced. Different kinds of structure for typical PU porous materials in sound absorption application are covered and highlighted, which include PU foam, modified PU porous materials, aerogel, templated PU, and special PU porous materials. Finally, the development direction and existing problems of PU material in sound absorption application are briefly prospected. It can be expected that porous PU with high sound absorption coefficient can be obtained by using some facile methods. The design and accurate regulation of porous structures or construction of multilayer sound absorption structure is favorably recommended to fulfill the high demand of industrial and commercial applications in the future work.

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