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1.
Mar Environ Res ; 202: 106807, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39504806

RESUMO

Seagrass sediment is intricately linked to their ecological functions, collectively forming the foundation of the seagrass ecosystem, and providing a range of essential ecosystem services, underscoring their significant research importance. This study aims to analyze the emerging hotspots and evolving trends in research on seagrass sediment over the past two decades (2003-2023), identify current research gaps, and forecast future directions for investigation. We extracted data from 3,390 studies identified in the Web of Science that have published pivotal research on seagrass sediment. Over this period, investigations into seagrass sediment have progressively transitioned from focusing on seagrass ecology to examining global change impacts on these sediments, ultimately shifting towards blue carbon research. Notably, there remains a paucity of studies addressing the sediments of small and tropical seagrasses. Furthermore, while the sedimentation mechanisms related to seagrasses represent an active area of inquiry, comprehensive analyses regarding these mechanisms are still limited. This study underscores the critical need for further exploration into sedimentation processes involving seagrasses as well as calls for enhanced integration within blue carbon ecosystem sediment studies pertaining to seagrass habitats.

2.
Microbiome ; 12(1): 202, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39407320

RESUMO

BACKGROUND: Entomopathogenic fungal infection-induced dysbiosis of host microbiota offers a window into understanding the complex interactions between pathogenic fungi and host symbionts. Such insights are critical for enhancing the efficacy of mycoinsecticides. However, the utilization of these interactions in pest control remains largely unexplored. RESULTS: Here, we found that infection by the host-specialist fungus Metarhizium acridum alters the composition of the symbiotic microbiota and increases the dominance of some bacterial symbionts in locusts. Meanwhile, M. acridum also effectively limits the overgrowth of the predominant bacteria. Comparative transcriptomic screening revealed that the fungus upregulates the production of MaCFEM1, an iron-binding protein, in the presence of bacteria. This protein sequesters iron, thereby limiting its availability. Functionally, overexpression of MaCFEM1 in the fungus induces iron deprivation, which significantly suppresses bacterial growth. Conversely, MaCFEM1 knockout relieves the restriction on bacterial iron availability, resulting in iron reallocation. Upon ΔMaCFEM1 infection, some host bacterial symbionts proliferate uncontrollably, turning into opportunistic pathogens and significantly accelerating host death. CONCLUSIONS: This study elucidates the critical role of pathogenic fungal-dominated iron allocation in mediating the shift of host microbes from symbiosis to pathogenicity. It also highlights a unique biocontrol strategy that jointly exploits pathogenic fungi and bacterial symbionts to increase host mortality. Video Abstract.


Assuntos
Bactérias , Proteínas Fúngicas , Ferro , Metarhizium , Simbiose , Ferro/metabolismo , Animais , Metarhizium/genética , Metarhizium/metabolismo , Metarhizium/patogenicidade , Metarhizium/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Gafanhotos/microbiologia , Interações Hospedeiro-Patógeno , Disbiose/microbiologia
3.
ACS Biomater Sci Eng ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39373322

RESUMO

Dicalcium phosphate anhydrous (DCPA) presents good biomineralization ability, the strontium element is known for superior bone affinity, and a whisker possesses good mechanical strength; all these are beneficial for improving the drawbacks of hydroxyapatite (HAP) like weaker mechanical properties, poor biomineralization, and slower degradation/absorption. Therefore, a homogeneous precipitation was adopted to synthesize Sr-substituted and DCPA and HAP coexisting whiskers. The composition, structure, and morphology based on urea dosage and substitution content were characterized, and the roles of DCPA, Sr, and whisker shape were investigated. It turned out that Sr-DCPA/HAP biphasic products contained about 19% DCPA and 81% HAP, and both phases occupied the outer and inner parts of the whisker, respectively. Increasing the urea dosage made the morphology transform from a sea urchin shape to fiber clusters and then whiskers, while Sr substitution brought the whisker back to the porous microsphere shape. Only 5% of Sr content and 15 g of urea could maintain the whisker shape. Sr could promote the proliferation of MC3T3-E1 cells even at a higher extract concentration of 10 mg/mL. The cells stayed in a healthy state whether cocultured with the whisker or the microsphere. The unstable DCPA combined with the decreased crystallinity brought by Sr doping contributed to shortening the apatite deposition period to within 7 days. The whisker morphology enhanced the compressive strength of acrylic resin, and the apatite layer helped to reduce the strength loss during soaking. The Sr-DCPA/HAP biphasic whisker with enhanced overall properties possessed more promising potential for biomedical application.

4.
Langmuir ; 40(43): 22582-22590, 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39422971

RESUMO

Microplastics (MPs) pollution has emerged as a pressing environmental concern in recent years. Owing to their minute dimensions, conventional plastic remediation approaches are inadequate for addressing the challenges posed by MPs. Herein, spherical (BOC-S) and nanosheet (BOC-N) BiOCl photocatalysts were prepared and applied to the degradation of poly(ethylene terephthalate) (PET) MPs after hydrothermal pretreatment. The results indicated that the degradation efficiency of pretreated PET MPs using BOC-S and BOC-N photocatalysts was 8.8 and 6.9 times that of the unpretreated MPs under the same conditions. Comparative experiments confirmed the excellent performance of the photocatalysis-pretreatment system. The creation of pores on the surface of pretreated PET MPs facilitates the entry of active substances into the interior to cause damage, while the enhancement of hydrophilicity and specific surface area facilitates the contact between the catalyst and PET MPs, thus increasing the degradation efficiency. Free radical trapping experiments revealed that hydroxyl radicals (·OH) produced by photocatalysis had the greatest influence on the degradation performance of pretreated PET MPs. Finally, a possible photocatalytic degradation mechanism for PET MPs was proposed. This research offers a novel perspective on MPs degradation, providing valuable insights for advancing the efficacy of the process.

5.
Polymers (Basel) ; 16(20)2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39458756

RESUMO

A key challenge in the utilization of waste polyester fibers (PET fibers) is the development of fiber-reinforced composites with high filler content and the improvement of fiber length retention. Herein, the effects of a two-rotor continuous mixer and a twin-screw extruder on the structure and properties of waste polyester fiber composites were evaluated. The results revealed that the mechanical properties of the composites were improved significantly with increasing fiber content, especially when processed using the twin-rotor continuous mixer. This mixer facilitated the formation of a robust fiber network structure, leading to substantial enhancements in tensile strength, flexural strength, and heat resistance. Specifically, compared to those processed by the twin-screw extruder, with 60 wt% fibers content, the tensile and flexural strengths of specimens processed by the twin-rotor continuous mixer increase by 21% and 13%, respectively. The average fiber length in specimens processed by the twin-rotor continuous mixer was 32% longer than that in specimens processed by the twin-screw extruder, attributable to the lower shear frequency and the higher tensile ratio of the former. This blending technique emerges as an effective strategy, contributing significantly to promoting the development and practical application of waste textile fiber-reinforced polymer composites.

6.
RSC Adv ; 14(44): 32389-32397, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39403160

RESUMO

Water resources are vital for sustainable human life and economic activities. However, the issue of water pollution has reached alarming levels. Coking wastewater, known for its high concentrations of organic matter and toxic substances, poses significant environmental hazards. In response to this challenge, we developed a novel composite flocculant called polymeric aluminum ferric chloride (PAFC)/rice straw (PAFC/RS) from fly ash (a coal waste) and rice straw (an agricultural waste). The PAFC/RS was characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Fourier transformed infrared (FT-IR). The flocculation performance of PAFC/RS was studied utilizing humic acid simulated coking wastewater as the target by measuring the chemical oxygen demand (COD), UV254, and turbidity. A removal efficiency of 97.3% for turbidity, 79.7% for COD, and 98.2% for UV254 was reached for the PAFC/RS with an optimal composition. It demonstrated a better flocculation effect compared to the traditional aluminum-iron-based inorganic flocculant. The PAFC/RS possesses great potential for a straightforward, cost-effective, and environmentally friendly water treatment material.

7.
Angew Chem Int Ed Engl ; : e202415221, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39324946

RESUMO

A zinc (Zn) metal anode paired with a vanadium oxide (VOx) cathode is a promising system for aqueous Zn-ion batteries (AZIBs); however, side reactions proliferating on the Zn anode surface and the infinite dissolution of the VOx cathode destabilise the battery system. Here, we introduce a multi-functional additive into the ZnSO4 (ZS) electrolyte, KAl(SO4)2 (KASO), to synchronise the in situ construction of the protective layer on the surface of the Zn anode and the VOx cathode. Theoretical calculations and synchrotron radiation have verified that the high-valence Al3+ plays dual roles of competing with Zn2+ for solvation and forming a Zn-Al alloy layer with a homogeneous electric field on the anode surface to mitigate the side reactions and dendrite generation. The Al-containing cathode-electrolyte interface (CEI) considerably alleviates the irreversible dissolution of the VOx cathode and the accumulation of byproducts. Consequently, the Zn||Zn cell with KASO exhibits an ultra-long cycle of 6000 h at 2 mA cm-2. Importantly, the VOx cathodes (VO2, V2O5 and NH4V4O10) in the ZS-KASO electrolyte showed excellent cycling stability, including Zn powder||VO2 cells and Zn||VO2 pouch cells. Even better, the full cell exhibits excellent cycling stability at low negative/positive (N/P) ratio of 2.83 and high mass loading (~16 mg cm-2). This study offers a straightforward and practical reference for concurrently addressing challenges at the anode and cathode of AZIBs.

8.
J Ethnopharmacol ; 335: 118712, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-39173724

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Yajieshaba (YJSB), approved by the Yunnan Provincial Food and Drug Administration in 2008, are known for their anti-inflammatory, antiviral, and pro-apoptotic properties, effectively treating Hepatic fibrosis (HF). However, its mechanism of action remains unclear. AIM OF THE STUDY: The objective of this investigation is to explore how YJSB influences the TGF-ß1/Smad signaling pathway as a strategy for reducing HF. METHODS: The establishment of a HF model in mice involved ligation of the common bile duct, followed by administration of YJSB. Body and liver weights were measured, and the liver index calculated. Serum levels of ALT, AST, ALP, TBA, and TBIL were assessed using colorimetric methods. Additionally, liver homogenates were analyzed for PIIINP, Col-IV, LN, HA, and Hyp, as well as TGF-ß1 activity, using ELISA. Histological analyses of liver sections, stained with H&E, Ag, and Masson's trichrome, were performed to examine inflammation and the accumulation of collagen and reticular fibers. These studies aimed to elucidate the pharmacodynamic effects of YJSB on HF in mice with bile duct obstruction. The target pathways of YJSB were preliminarily identified through immunofluorescence detection of TGF-ß1, P-Smad2L, P-Smad2C, P-Smad3L, P-Smad3C, and Smad4 proteins. In vitro experiments included the induction of hepatic stellate cell (HSC-T6) activation by H2O2. A cell injury model was established for HSC-T6, and the CCK-8 assay was used to determine the optimal YJSB concentration and treatment duration. After pirfenidone (PFD) administration, which inhibits the TGF-ß1/Smad pathway, the effects of YJSB on HSC-T6 cell proliferation were observed. ELISA assays quantified Col-III, α-SMA, and Col-I in cell lysates to assess YJSB's impact on collagen synthesis in HSC-T6 cells. Western blot analysis was performed to assess the protein levels within the TGF-ß1/Smad signaling cascade. RESULTS: In the HF mouse model, administration of YJSB notably augmented the body weight and reduced the liver index. Concurrently, there was an elevation in serum concentrations of ALP, AST, ALT, TBA, and TBIL. Similarly, in the liver homogenates of HF mice, increases were observed in the levels of HA, PIIINP, Col-IV, LN, Hyp, and TGF-ß1. Histological assessments using H&E, Ag, and Masson stains indicated a substantial diminution in liver tissue damage. Through immunofluorescence analysis, it was discerned that YJSB modulated the expression of TGF-ß1, P-Smad2L, P-Smad2C, and P-Smad3L downwards, while elevating P-Smad3C and Smad4 protein expressions. Additional investigations revealed a significant reduction in α-SMA, Col-I, and Col-III levels in cell culture fluids, suggesting a decrease in collagen synthesis and a protective role against cellular damage. Western blot analyses demonstrated that the TGF-ß1/Smad pathway inhibitor, PFD, acted in synergy with YJSB, enhancing its regulatory effects on this pathway, decreasing levels of TGF-ß1, P-Smad2L, P-Smad2C, P-Smad3L, and promoting the expression of P-Smad3C. CONCLUSIONS: YJSB demonstrates a pharmacodynamic effect against HF, enhancing liver functionality and effectively mitigating the damage associated with bile duct obstruction. The proposed action mechanism of YJSB involves modulation of the TGF-ß1/Smad signaling pathway. Research indicates that YJSB might play a role in suppressing the movement, programmed cell death, and activation of HSC-T6, potentially decelerating the advancement of hepatic fibrosis.


Assuntos
Colestase , Células Estreladas do Fígado , Peróxido de Hidrogênio , Cirrose Hepática , Transdução de Sinais , Fator de Crescimento Transformador beta1 , Animais , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Fator de Crescimento Transformador beta1/metabolismo , Camundongos , Masculino , Peróxido de Hidrogênio/metabolismo , Colestase/metabolismo , Colestase/patologia , Colestase/tratamento farmacológico , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Transdução de Sinais/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Linhagem Celular , Modelos Animais de Doenças , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Proteínas Smad/metabolismo , Camundongos Endogâmicos C57BL , Proteína Smad2/metabolismo
9.
Redox Biol ; 75: 103260, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38955114

RESUMO

Tumor metabolic reprogramming requires high levels of adenosine triphosphate (ATP) to maintain treatment resistance, which poses major challenges to chemotherapy and photothermal therapy. Especially, high levels of ATP promote copper ion efflux for limiting the curative effect of cuproptosis. Here, an H2S-responsive mesoporous Cu2Cl(OH)3-loading chemotherapeutic cisplatin (CDDP) was synthesized, and the final nanoparticle, CDDP@Cu2Cl(OH)3-CDs (CDCuCDs), was encapsulated by electrostatic action with carbon dots (CDs). CDCuCDs reacted with overproduction H2S in colon tumor to produce photothermic copper sulfide for photothermal therapy. CDDP was released by lysis to achieve chemotherapeutic effects. Importantly, CDDP elevated H2O2 levels in cells through a cascade reaction and continuously transforms H2O2 into highly cytotoxic •OH through chemodynamic therapy between H2O2 and Cu+, which enables nanoparticles to generate •OH and improve the chemotherapeutic efficacy. Highly toxic •OH disrupts mitochondrial homeostasis, prohibiting it from performing normal energy-supplying functions. Down-regulated ATP inhibits heat shock protein expression, which promotes the therapeutic effect of mild photothermal therapy and reduces the efflux of intracellular copper ions, thus improving the therapeutic effect of cuproptosis. Our research provides a potential therapeutic strategy using overproduction H2S responses in tumors, allowing tumor microenvironment-activated •OH nanogenerators to promote tumor energy remodeling for cancer treatment.


Assuntos
Cobre , Estresse Oxidativo , Terapia Fototérmica , Microambiente Tumoral , Terapia Fototérmica/métodos , Microambiente Tumoral/efeitos dos fármacos , Cobre/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Humanos , Animais , Camundongos , Linhagem Celular Tumoral , Nanopartículas/química , Cisplatino/farmacologia , Peróxido de Hidrogênio/metabolismo
11.
J Ethnopharmacol ; 335: 118611, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-39053712

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Allergic rhinitis (AR) stands as a non-infectious inflammatory condition affecting the nasal mucosa, marked by bouts of sneezing, nasal itching, and congestion. This ailment afflicts individuals across all age groups and poses challenges for effective treatment due to its chronic nature. Cangerzisan (CEZS), documented in the Jishengfang compendium, represents a traditional Chinese medicinal formula long utilized for AR management. AIM OF THE STUDY: Investigating mechanism beneath therapeutic effect of CEZS in alleviating AR. MATERIALS AND METHODS: The main active components in CEZS were determined by High Performance Liquid Chromatography (HPLC).The active constituents of CEZS and their corresponding targets were identified through an exhaustive screening process employing TCMSP database. To identify targets relevant to AR, GeneCards, OMIM, and DisGeNET databases were thoroughly applied. Protein-protein interaction (PPI) network was assembled utilizing STRING platform. Potential signaling pathways influenced by CEZS were delineated through GO and KEGG enrichment analyses. Subsequently, an AR model was induced by administering aluminum hydroxide (Al(OH)3) and ovalbumin (OVA) for affecting basal and local sensitization, respectively, facilitating experimental validation of the principal signaling pathways. RESULTS: There were 61 active constituents identified within CEZS, targeting a pool of 129 entities associated with AR treatment. Pathways analysis of KEGG revealed that CEZS potentially inhibits AR advancement via modulating TLR4 signaling pathway. Animal experiments demonstrated that CEZS effectively alleviated symptom scores in guinea pigs with AR. Moreover, it exhibited notable improvements in serum immune and inflammatory factors levels, as well as reduced inflammatory infiltration within nasal mucosa, including goblet and mast cells. CEZS was found to enhance GATA-3 expression while reducing T-bet expression, thereby modulating the TH1/TH2 immune balance. Additionally, CEZS downregulated HMGB1, TLR4, and p-NF-κB/NF-κB protein expressions within nasal mucosa of guinea pigs. CONCLUSIONS: The therapeutic mechanism of CEZS against AR involves rectifying TH1/TH2 immune imbalance and upregulating inflammatory and immune factors through modulating key proteins expression within TLR4 pathway. This targeted regulation effectively impedes AR progression.


Assuntos
Farmacologia em Rede , Rinite Alérgica , Animais , Rinite Alérgica/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/química , Mapas de Interação de Proteínas , Transdução de Sinais/efeitos dos fármacos , Ovalbumina , Masculino , Feminino , Receptor 4 Toll-Like/metabolismo , Modelos Animais de Doenças , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/metabolismo , Mucosa Nasal/imunologia , Cobaias , Antialérgicos/farmacologia , Citocinas/metabolismo
12.
Antioxidants (Basel) ; 13(7)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39061921

RESUMO

Ferulic acid is a ubiquitous ingredient in cereals, vegetables, fruits and Chinese herbal medicines. Due to the ferulic phenolic nucleus coupled to an extended side chain, it readily forms a resonant-stable phenoxy radical, which explains its potent antioxidant potential. In addition, it also plays an important role in anti-cancer, pro-angiogenesis, anti-thrombosis, neuroprotection, food preservation, anti-aging, and improving the antioxidant performance of livestock and poultry. This review provides a comprehensive summary of the structure, mechanism of antioxidation, application status, molecular mechanism of pharmacological activity, existing problems, and application prospects of ferulic acid and its derivatives. The aim is to establish a theoretical foundation for the utilization of ferulic acid in medicine, food, cosmetics, livestock, and poultry.

13.
Redox Biol ; 74: 103229, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38870781

RESUMO

BACKGROUND: Nuclear erythroid 2-related factor 2 (Nrf2), a transcription factor, is critically involved in the regulation of oxidative stress and inflammation. However, the role of endothelial Nrf2 in atherogenesis has yet to be defined. In addition, how endothelial Nrf2 is activated and whether Nrf2 can be targeted for the prevention and treatment of atherosclerosis is not explored. METHODS: RNA-sequencing and single-cell RNA sequencing analysis of mouse atherosclerotic aortas were used to identify the differentially expressed genes. In vivo endothelial cell (EC)-specific activation of Nrf2 was achieved by injecting adeno-associated viruses into ApoE-/- mice, while EC-specific knockdown of Nrf2 was generated in Cdh5CreCas9floxed-stopApoE-/- mice. RESULTS: Endothelial inflammation appeared as early as on day 3 after feeding of a high cholesterol diet (HCD) in ApoE-/- mice, as reflected by mRNA levels, immunostaining and global mRNA profiling, while the immunosignal of the end-product of lipid peroxidation (LPO), 4-hydroxynonenal (4-HNE), started to increase on day 10. TNF-α, 4-HNE, and erastin (LPO inducer), activated Nrf2 signaling in human ECs by increasing the mRNA and protein expression of Nrf2 target genes. Knockdown of endothelial Nrf2 resulted in augmented endothelial inflammation and LPO, and accelerated atherosclerosis in Cdh5CreCas9floxed-stopApoE-/- mice. By contrast, both EC-specific and pharmacological activation of Nrf2 inhibited endothelial inflammation, LPO, and atherogenesis. CONCLUSIONS: Upon HCD feeding in ApoE-/- mice, endothelial inflammation is an earliest event, followed by the appearance of LPO. EC-specific activation of Nrf2 inhibits atherosclerosis while EC-specific knockdown of Nrf2 results in the opposite effect. Pharmacological activators of endothelial Nrf2 may represent a novel therapeutic strategy for the treatment of atherosclerosis.


Assuntos
Apolipoproteínas E , Aterosclerose , Células Endoteliais , Inflamação , Peroxidação de Lipídeos , Fator 2 Relacionado a NF-E2 , Animais , Humanos , Masculino , Camundongos , Apolipoproteínas E/genética , Apolipoproteínas E/deficiência , Apolipoproteínas E/metabolismo , Aterosclerose/metabolismo , Aterosclerose/genética , Aterosclerose/patologia , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Inflamação/metabolismo , Inflamação/genética , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo
14.
ChemSusChem ; : e202400512, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878218

RESUMO

Massive accumulation of postconsumer plastic waste in eco-system has raised growing environmental concerns. Sustainable end-of-life managements of the indispensable plastic are highly demanding and challenging in modern society. To relieve the plastic menace, herein we present a full life cycle sustainable supramolecular bioplastic made from biomass-derived polyelectrolyte (chitosan quaternary ammonium salt, QCS) and natural sodium fatty acid (sodium laurate, SL) through solid-phase molecular self-assembly (SPMSA), by which the QCS-SL complexes, precipitated from mixing the aqueous solutions, self-assemble to form bioplastic film by mildly pressing at room temperature. The QCS-SL bioplastic films display superior hydroplasticity owing to the water-activated molecular rearrangement and electrostatic bond reconstruction, which allows facile self-healing and reprocessing at room temperature to significantly extend the service lifetime of both products and raw materials. With higher water content, the dynamic electrostatic interactions and precipitation-dissolution equilibrium endow the QCS-SL bioplastic films with considerable solubility in water, which is promising to mitigate the plastic accumulation in aquatic environment. Because both QCS and SL are biocompatible and biodegradable, the dissolved QCS-SL films are nontoxic and environmentally friendly. Thus, this novel supramolecular bioplastic is highly sustainable throughout the whole life cycle, which is expected to open a new vista in sustainable plastic materials.

15.
Cell Metab ; 36(8): 1668-1678.e5, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38901423

RESUMO

Diet may promote brain health in metabolically impaired older individuals. In an 8-week randomized clinical trial involving 40 cognitively intact older adults with insulin resistance, we examined the effects of 5:2 intermittent fasting and the healthy living diet on brain health. Although intermittent fasting induced greater weight loss, the two diets had comparable effects in improving insulin signaling biomarkers in neuron-derived extracellular vesicles, decreasing the brain-age-gap estimate (reflecting the pace of biological aging of the brain) on magnetic resonance imaging, reducing brain glucose on magnetic resonance spectroscopy, and improving blood biomarkers of carbohydrate and lipid metabolism, with minimal changes in cerebrospinal fluid biomarkers for Alzheimer's disease. Intermittent fasting and healthy living improved executive function and memory, with intermittent fasting benefiting more certain cognitive measures. In exploratory analyses, sex, body mass index, and apolipoprotein E and SLC16A7 genotypes modulated diet effects. The study provides a blueprint for assessing brain effects of dietary interventions and motivates further research on intermittent fasting and continuous diets for brain health optimization. For further information, please see ClinicalTrials.gov registration: NCT02460783.


Assuntos
Encéfalo , Dieta Saudável , Jejum Intermitente , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores/sangue , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Cognição/fisiologia , Resistência à Insulina , Jejum Intermitente/fisiologia , Imageamento por Ressonância Magnética
16.
RSC Adv ; 14(21): 15143-15154, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38725564

RESUMO

Ethylene-vinyl acetate copolymer (EVA) is widely used in various applications; however, its flammability limits its application in wire and cable industries. In this study, 3-methacryloxypropyltrimethoxysilane (KH570) was successfully grafted onto the surface of anhydrous magnesium carbonate (AMC) by alkali activation treatment. The KH570 modified AMC (AMC@KH570) was then introduced into the EVA matrix along with hexaphenoxycyclotriphosphazene (HPCTP) to assess their effects on the flame retardancy and mechanical properties of EVA composites. The results illustrate a significant synergistic effect in enhancing the flame retardancy of EVA composites by using AMC@KH570 and HPCTP, and the limiting oxygen index (LOI) and vertical burning test (UL-94) of EVA filled with 5 wt% HPCTP and 45 wt% AMC@KH570 (mAMC/H-45-5) reached 27.6% and V-0, respectively. The flame retardant mechanism was investigated by thermogravimetric/infrared (TG-IR) spectroscopy and residual carbon composition analysis. The results show that the thermal decomposition of AMC@KH570 and HPCTP consists of gas dilution, free radical quenching, and catalytic carbonization. Furthermore, KH570 works as a bridge to improve the compatibility of AMC and EVA matrix, which offsets the mechanical loss of EVA to some extent. The present research provides a new path to modify AMC and fabricate EVA composites with excellent flame retardant properties.

17.
Int J Biol Macromol ; 271(Pt 2): 132375, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759855

RESUMO

Anti-counterfeiting in 3D printing has gained significant attention, however, current approaches often fall short of fully capitalizing on the inherent advantages of personalized manufacturing with this technology. Herein, we propose an embedded anti-counterfeiting scheme for additive manufacturing, accompanied by a novel fluorescent encrypted quick response (QR) method. This approach involves the development of a 3D printing filament utilizing poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) bio-composites as the primary filament matrix, with varying quantities of Chlorella powder incorporated. The resulting filament has a good thermal stability near 200 °C and exhibits a distinctive red fluorescence under ultraviolet light, with the emission peak at 677 nm when excited by 415 nm blue light. Fluorescence imaging analysis confirms that the red fluorescence in 3D printed devices containing Chlorella is a result of the chlorophyll and its derivatives fluorescence effect. The fluorescent encrypted QR codes are inconspicuous in daylight but become easily discernible under ultraviolet light. In the cases of recognizable QR codes, the ∆Eab* values all exceed 35, and the LC/LB values deviate significantly from 1. This research delves into the fluorescence characteristics of Chlorella and highlights its applicability in 3D printing, specifically within the realm of product anti-counterfeiting, presenting a groundbreaking approach.


Assuntos
Chlorella , Poliésteres , Impressão Tridimensional , Poliésteres/química , Chlorella/química , Fluorescência
18.
Life Sci ; 349: 122723, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754816

RESUMO

Endothelial dysfunction is the most common pathological feature of cardiovascular diseases, including diabetes mellitus, hypertension and atherosclerosis. It affects both macro- and micro-vasculatures, causing functional impairment of multiple organs. Pien Tze Huang (PZH) is a well-studied traditional Chinese medicine (TCM) with multiple pharmacological properties that produces therapeutic benefits against colorectal cancer, non-alcoholic steatohepatitis and neurodegenerative diseases. However, it is unknown how PZH affects vascular function under pathological conditions. Therefore, this study aimed to investigate the effect of PZH on endothelial function and the underlying mechanisms in db/db diabetic mice. The results showed that chronic treatment of PZH (250 mg/kg/day, 5 weeks) improved endothelial function by restoring endothelium-dependent relaxation through the activation of the Akt-eNOS pathway and inhibition of endothelial oxidative stress, which increased nitric oxide bioavailability. Furthermore, PZH treatment increased insulin sensitivity and suppressed inflammation in diabetic mice. These new findings suggest that PZH may have vaso-protective properties and the potential to protect against diabetic vasculopathy by preserving endothelial function.


Assuntos
Diabetes Mellitus Experimental , Medicamentos de Ervas Chinesas , Endotélio Vascular , Estresse Oxidativo , Animais , Camundongos , Medicamentos de Ervas Chinesas/farmacologia , Masculino , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Endotélio Vascular/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Resistência à Insulina
19.
Cell ; 187(13): 3409-3426.e24, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38744281

RESUMO

Alterations in extracellular matrix (ECM) architecture and stiffness represent hallmarks of cancer. Whether the biomechanical property of ECM impacts the functionality of tumor-reactive CD8+ T cells remains largely unknown. Here, we reveal that the transcription factor (TF) Osr2 integrates biomechanical signaling and facilitates the terminal exhaustion of tumor-reactive CD8+ T cells. Osr2 expression is selectively induced in the terminally exhausted tumor-specific CD8+ T cell subset by coupled T cell receptor (TCR) signaling and biomechanical stress mediated by the Piezo1/calcium/CREB axis. Consistently, depletion of Osr2 alleviates the exhaustion of tumor-specific CD8+ T cells or CAR-T cells, whereas forced Osr2 expression aggravates their exhaustion in solid tumor models. Mechanistically, Osr2 recruits HDAC3 to rewire the epigenetic program for suppressing cytotoxic gene expression and promoting CD8+ T cell exhaustion. Thus, our results unravel Osr2 functions as a biomechanical checkpoint to exacerbate CD8+ T cell exhaustion and could be targeted to potentiate cancer immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Fatores de Transcrição , Animais , Feminino , Humanos , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Matriz Extracelular/metabolismo , Histona Desacetilases/metabolismo , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Exaustão das Células T , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Estresse Mecânico
20.
Mater Horiz ; 11(14): 3386-3395, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38689529

RESUMO

High-power electronic architectures and devices require elastic thermally conductive materials. The use of epoxy resin in thermal management is limited due to its rigidity. Here, based on epoxy vitrimer, flexible polyethylene glycol (PEG) chains are introduced into covalent adaptable networks to construct covalent-noncovalent interpenetrating networks, enabling the elasticity of epoxy resins. Compared to traditional silicone-based thermal interface materials, the newly developed elastic epoxy resin shows the advantages of reprocessability, self-healing, and no small molecule release. Results show that, even after being filled with boron nitride and liquid metal, the material maintains its resilience, reprocessability and self-healing properties. Leveraging these characteristics, the composite can be further processed into thin films through a repeated pressing-rolling technique that facilitates the forced orientation of the fillers. Subsequently, the bulk composites are reconstructed using a film-stacking method. The results indicate that the thermal conductivity of the reconstructed bulk composite reaches 3.66 W m-1 K-1, achieving a 68% increase compared to the composite prepared through blending. Due to the existence of covalent adaptable networks, the inorganic and inorganic components of the composite prepared in this work can be completely separated under mild conditions, realizing closed-loop recycling.

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