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1.
J Lipid Res ; 65(6): 100559, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729351

RESUMO

Adipogenesis is one of the major mechanisms for adipose tissue expansion, during which spindle-shaped mesenchymal stem cells commit to the fate of adipocyte precursors and differentiate into round-shaped fat-laden adipocytes. Here, we investigated the lipidomic profile dynamics of ex vivo-differentiated brown and white adipocytes derived from the stromal vascular fractions of interscapular brown (iBAT) and inguinal white adipose tissues. We showed that sphingomyelin was specifically enriched in terminally differentiated brown adipocytes, but not white adipocytes. In line with this, freshly isolated adipocytes of iBAT showed higher sphingomyelin content than those of inguinal white adipose tissue. Upon cold exposure, sphingomyelin abundance in iBAT gradually decreased in parallel with reduced sphingomyelin synthase 1 protein levels. Cold-exposed animals treated with an inhibitor of sphingomyelin hydrolases failed to maintain core body temperature and showed reduced oxygen consumption and iBAT UCP1 levels. Conversely, blockade of sphingomyelin synthetic enzymes resulted in enhanced nonshivering thermogenesis, reflected by elevated body temperature and UCP1 levels. Taken together, our results uncovered a relation between sphingomyelin abundance and fine-tuning of UCP1-mediated nonshivering thermogenesis.


Assuntos
Esfingomielinas , Termogênese , Proteína Desacopladora 1 , Animais , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 1/genética , Esfingomielinas/metabolismo , Camundongos , Masculino , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Marrom/metabolismo , Camundongos Endogâmicos C57BL
2.
Small ; : e2403971, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012083

RESUMO

Developing low-cost and industrially viable electrode materials for efficient water-splitting performance and constructing intrinsically active materials with abundant active sites is still challenging. In this study, a self-supported porous network Ni(OH)2-CeOx heterostructure layer on a FeOOH-modified Ni-mesh (NiCe/Fe@NM) electrode is successfully prepared by a facile, scalable two-electrode electrodeposition strategy for overall alkaline water splitting. The optimized NiCe0.05/Fe@NM catalyst reaches a current density of 100 mA cm-2 at an overpotential of 163 and 262 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, in 1.0 m KOH with excellent stability. Additionally, NiCe0.05/Fe@NM demonstrates exceptional HER performance in alkaline seawater, requiring only 148 mV overpotential at 100 mA cm-2. Under real water splitting conditions, NiCe0.05/Fe@NM requires only 1.701 V to achieve 100 mA cm-2 with robust stability over 1000 h in an alkaline medium. The remarkable water-splitting performance and stability of the NiCe0.05/Fe@NM catalyst result from a synergistic combination of factors, including well-optimized surface and electronic structures facilitated by an optimal Ce ratio, rapid reaction kinetics, a superhydrophilic/superaerophobic interface, and enhanced intrinsic catalytic activity. This study presents a simple two-electrode electrodeposition method for the scalable production of self-supported electrocatalysts, paving the way for their practical application in industrial water-splitting processes.

3.
New Phytol ; 242(2): 786-796, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38451101

RESUMO

Molecular genetic understanding of flowering time regulation is crucial for sorghum development. GRAIN NUMBER, PLANT HEIGHT AND HEADING DATE 7 (SbGhd7) is one of the six classical loci conferring photoperiod sensitivity of sorghum flowering. However, its functions remain poorly studied. The molecular functions of SbGhd7 were characterized. The gene regulatory network controlled by SbGhd7 was constructed and validated. The biological roles of SbGhd7 and its major targets were studied. SbGhd7 overexpression (OE) completely prevented sorghum flowering. Additionally, we show that SbGhd7 is a major negative regulator of flowering, binding to the promoter motif TGAATG(A/T)(A/T/C) and repressing transcription of the major florigen FLOWERING LOCUS T 10 (SbFT10) and floral activators EARLY HEADING DATE (SbEhd1), FLAVIN-BINDING, KELCH REPEAT, F-BOX1 (SbFKF1) and EARLY FLOWERING 3 (SbELF3). Reinforcing the direct effect of SbGhd7, SbEhd1 OE activated the promoters of three functional florigens (SbFT1, SbFT8 and SbFT10), dramatically accelerating flowering. Our studies demonstrate that SbGhd7 is a major repressor of sorghum flowering by directly and indirectly targeting genes for flowering activation. The mechanism appears ancient. Our study extends the current model of floral transition regulation in sorghum and provides a framework for a comprehensive understanding of sorghum photoperiod response.


Assuntos
Sorghum , Sorghum/metabolismo , Proteínas de Plantas/metabolismo , Flores/fisiologia , Florígeno/metabolismo , Fotoperíodo , Regulação da Expressão Gênica de Plantas
4.
Fish Shellfish Immunol ; 147: 109436, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369071

RESUMO

IFN-γ plays a crucial role in both innate and adaptive immune responses and is a typical Th1 cytokine that promotes Th1 response and activates macrophages. When macrophages were incubated with IFN-γ, their phagocytosis ratio against Mycobacterium marinum increased significantly, as observed under fluorescence microscopy. The macrophages engulfed a large number of M. marinum. The proliferative ability of macrophages treated with IFN-γ was significantly weaker on the 4th and 7th day after phagocytosis and subsequent re-infection with marine chlamydia (P < 0.001). This suggests that IFN-γ enhances the phagocytosis and killing ability of macrophages against M. marinum. IFN-γ protein also significantly increased the production of reactive oxygen species (H2O2) and nitric oxide (NO) by macrophages. Additionally, the expression levels of toll-like receptor 2 (tlr2) and caspase 8 (casp8) were significantly higher in macrophages after IFN-γ incubation compared to direct infection after 12 h of M. marinum stimulation. Apoptosis was also observed to a higher degree in IFN-γ incubated macrophage. Moreover, mRNA expression of major histocompatibility complex (MHC) molecules produced by macrophages after IFN-γ incubation was significantly higher than direct infection. This indicates that IFN-γ enhances antigen presentation by upregulating MHC expression. It also upregulates tlr2 and casp8 expression through the TLR2 signaling pathway to induce apoptosis in macrophages. The pro-inflammatory cytokine showed an initial increase followed by a decline, suggesting that IFN-γ enhances the immune response of macrophages against M. marinum infection. On the other hand, the anti-inflammatory cytokine showed a delayed increase, significantly reducing the expression of pro-inflammatory cytokines. The expression of both cytokines balanced each other and together regulated the inflammatory reaction against M. marinum infection.


Assuntos
Mycobacterium marinum , Receptor 2 Toll-Like , Animais , Receptor 2 Toll-Like/genética , Peróxido de Hidrogênio/metabolismo , Macrófagos , Citocinas/metabolismo
5.
J Dairy Sci ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851581

RESUMO

Hepatocellular lipid accumulation characterizes fatty liver in dairy cows. Lipid droplets (LD), specialized organelles that store lipids and maintain cellular lipid homeostasis, are responsible for the ectopic storage of lipids associated with several metabolic disorders. In recent years, non-ruminant studies have reported that LD-mitochondria interactions play an important role in lipid metabolism. Due to the role of diacylglycerol acyltransferase isoforms (DGAT1 and DGAT2) in LD synthesis, we explored mechanisms of mitochondrial fatty acid transport in ketotic cows using liver biopsies and isolated primary hepatocytes. Compared with healthy cows, cows with fatty liver had massive accumulation of LD and high protein expression of the triglyceride (TAG) synthesis-related enzymes DGAT1 and DGAT2, LD synthesis-related proteins perilipin 2 (PLIN2) and perilipin 5 (PLIN5), and the mitochondrial fragmentation-related proteins dynamin-related protein 1 (DRP1) and fission 1 (FIS1). In contrast, factors associated with fatty acid oxidation, mitochondrial fusion and mitochondrial electron transport chain complex were lower compared with those in the healthy cows. In addition, transmission electron microscopy revealed significant contacts between LD-mitochondria in liver tissue from cows with fatty liver. Compared with isolated cytoplasmic mitochondria, expression of carnitine palmitoyl transferase 1A (CPT1A) and DRP1 was lower, but mitofusin 2 (MFN2) and mitochondrial electron transport chain complex was greater in isolated peridroplet mitochondria from hepatic tissue of cows with fatty liver. In vitro data indicated that exogenous free fatty acids (FFA) induced hepatocyte LD synthesis and mitochondrial dynamics consistent with in vivo results. Furthermore, DGAT2 inhibitor treatment attenuated the FFA-induced upregulation of PLIN2 and PLIN5 and rescued the impairment of mitochondrial dynamics. Inhibition of DGAT2 also restored mitochondrial membrane potential and reduced hepatocyte reactive oxygen species production. The present in vivo and in vitro results indicated there are functional differences among different types of mitochondria in the liver tissue of dairy cows with ketosis. Activity of DGAT2 may play a key role in maintaining liver mitochondrial function and lipid homeostasis in dairy cows during the transition period.

6.
Eur Arch Otorhinolaryngol ; 281(4): 1877-1884, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38206391

RESUMO

OBJECTIVES: To assess and compare the effectiveness of various treatment approaches for laryngeal contact granulomas (LCG). METHODS: A retrospective analysis was conducted on a cohort of 45 patients diagnosed with LCG at the Second Affiliated Hospital of Xi'an Jiaotong University from October 2017 to May 2023. Based on the treatment modalities administered, patients were categorized into three groups: acid suppression alone, hormone injection combined with acid suppression, and surgery combined with acid suppression. Subsequently, the study compared differences in treatment efficacy and average healing time among these three groups, using various indicators. RESULTS: The findings indicate that the granuloma size in LCG patients with hoarseness (0.126, 95% CI 0.087-0.288) was significantly greater compared to LCG patients without hoarseness (0.047, 95% CI 0.014-0.083) (P = 0.001). However, there were no significant variations in age, morphology (unlobulated/lobulated), laterality ratio (left/right), sex ratio (male/female), history of tracheal intubation (non-intubation/intubation), and RFS score (RFS > 7/RFS ≤ 7) (P > 0.05), regardless of the presence of hoarseness symptoms. At the treatment observation endpoint of 3 months, the curative ratio in the group receiving hormone injection combined with acid suppression was found to be significantly higher compared to the group receiving acid suppression alone (P = 0.018). In addition, the average healing time of patients in the hormone injection combined with acid suppression group was notably shorter than that of the acid suppression alone group (P = 0.007). CONCLUSIONS: The combination of hormonal injections and acid suppression may enhance the curative ratio and expedite the healing time of LCG.


Assuntos
Granuloma Laríngeo , Rouquidão , Humanos , Masculino , Feminino , Estudos Retrospectivos , Rouquidão/etiologia , Rouquidão/terapia , Granuloma Laríngeo/cirurgia , Granuloma , Hormônios
7.
Sensors (Basel) ; 24(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39001056

RESUMO

In the process of metal wire and additive manufacturing, due to changes in temperature, humidity, current, voltage, and other parameters, as well as the failure of machinery and equipment, a failure may occur in the manufacturing process that seriously affects the current situation of production efficiency and product quality. Based on the demand for monitoring of the key impact parameters of additive manufacturing, this paper develops a parameter monitoring and prediction system for the additive manufacturing feeding process to provide a basis for future fault diagnosis. The fault diagnosis and prediction system for metal wire supply and additive manufacturing utilizes STM 32 as its core, enabling the capture and transmission of temperature, humidity, current, and voltage data. The upper computer system, designed on the LabVIEW 2019 virtual instrument platform, incorporates an LSTM neural network model and facilitates a connection between LabVIEW and MATLAB 2019 to achieve the prediction function. The monitoring and prediction system established in this study is intended to provide basic research assistance in the field of fault diagnosis.

8.
Elife ; 132024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470102

RESUMO

Perirenal adipose tissue (PRAT) is a unique visceral depot that contains a mixture of brown and white adipocytes. The origin and plasticity of such cellular heterogeneity remains unknown. Here, we combine single-nucleus RNA sequencing with genetic lineage tracing to reveal the existence of a distinct subpopulation of Ucp1-&Cidea+ adipocytes that arises from brown-to-white conversion during postnatal life in the periureter region of mouse PRAT. Cold exposure restores Ucp1 expression and a thermogenic phenotype in this subpopulation. These cells have a transcriptome that is distinct from subcutaneous beige adipocytes and may represent a unique type of cold-recruitable adipocytes. These results pave the way for studies of PRAT physiology and mechanisms controlling the plasticity of brown/white adipocyte phenotypes.


Assuntos
Adipócitos Bege , Tecido Adiposo , Camundongos , Animais , Tecido Adiposo/metabolismo , Adipócitos Brancos , Adipócitos Marrons/metabolismo , Termogênese/genética , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/fisiologia
9.
Front Neurosci ; 18: 1341109, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38595972

RESUMO

Amyotrophic lateral sclerosis is a fatal, multigenic, multifactorial neurodegenerative disease characterized by upper and lower motor neuron loss. Animal models are essential for investigating pathogenesis and reflecting clinical manifestations, particularly in developing reasonable prevention and therapeutic methods for human diseases. Over the decades, researchers have established a host of different animal models in order to dissect amyotrophic lateral sclerosis (ALS), such as yeast, worms, flies, zebrafish, mice, rats, pigs, dogs, and more recently, non-human primates. Although these models show different peculiarities, they are all useful and complementary to dissect the pathological mechanisms of motor neuron degeneration in ALS, contributing to the development of new promising therapeutics. In this review, we describe several common animal models in ALS, classified by the naturally occurring and experimentally induced, pointing out their features in modeling, the onset and progression of the pathology, and their specific pathological hallmarks. Moreover, we highlight the pros and cons aimed at helping the researcher select the most appropriate among those common experimental animal models when designing a preclinical ALS study.

10.
Front Public Health ; 12: 1363451, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38846605

RESUMO

Background: Public health emergencies have a lasting impact on a country's economic and social development. However, commercial insurance can disperse these negative consequences and reduce risk losses. Method: Based on the Chinese Household Tracking Survey and Peking University Digital Inclusive Finance Index, this study employed a difference-in-differences model to test the impact of the COVID-19 outbreak on commercial insurance participation and the impact mechanism. Results: The analysis showed that the outbreak of COVID-19 improved residents' risk perception, risk preference and digital finance and promoted their participation in commercial insurance, commercial endowment insurance, and commercial medical insurance. Conclusion: Major public health emergencies can increase commercial insurance participation, but the promotional effect of commercial insurance on rural and low-income individuals is relatively limited. To tap into potential customers, financial institutions should focus on vulnerable societal groups. This study supplements the relevant literature on the impact of major public health emergencies on commercial insurance participation.


Assuntos
COVID-19 , Emergências , Saúde Pública , Humanos , China/epidemiologia , COVID-19/epidemiologia , COVID-19/economia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Seguro Saúde/estatística & dados numéricos , Inquéritos e Questionários , SARS-CoV-2
11.
World J Psychiatry ; 14(5): 607-623, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38808079

RESUMO

Depression, a prevalent and complex mental health condition, presents a significant global health burden. Depression is one of the most frequent mental disorders; deaths from it account for 14.3% of people worldwide. In recent years, the integration of complementary and alternative medicine, including traditional Chinese medicine (TCM), has gained attention as a potential avenue for addressing depression. This comprehensive review critically assesses the efficacy of TCM interventions in alleviating depressive symptoms. An in-depth look at different research studies, clinical trials, and meta-analyses is used in this review to look into how TCM practices like herbal formulations, acupuncture, and mind-body practices work. The review looks at the quality of the evidence, the rigor of the methods, and any possible flaws in the current studies. This gives us an idea of where TCM stands right now in terms of treating depression. This comprehensive review aims to assess the efficacy of TCM interventions in alleviating depressive symptoms. In order to learn more about their possible healing effects, the study also looks into how different types of TCM work, such as herbal formulas, acupuncture, and mind-body practices.

12.
Mol Metab ; 81: 101890, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307384

RESUMO

BACKGROUND & AIMS: Genome-wide studies have identified three missense variants in the human gene ACVR1C, encoding the TGF-ß superfamily receptor ALK7, that correlate with altered waist-to-hip ratio adjusted for body mass index (WHR/BMI), a measure of body fat distribution. METHODS: To move from correlation to causation and understand the effects of these variants on fat accumulation and adipose tissue function, we introduced each of the variants in the mouse Acvr1c locus and investigated metabolic phenotypes in comparison with a null mutation. RESULTS: Mice carrying the I195T variant showed resistance to high fat diet (HFD)-induced obesity, increased catecholamine-induced adipose tissue lipolysis and impaired ALK7 signaling, phenocopying the null mutants. Mice with the I482V variant displayed an intermediate phenotype, with partial resistance to HFD-induced obesity, reduction in subcutaneous, but not visceral, fat mass, decreased systemic lipolysis and reduced ALK7 signaling. Surprisingly, mice carrying the N150H variant were metabolically indistinguishable from wild type under HFD, although ALK7 signaling was reduced at low ligand concentrations. CONCLUSION: Together, these results validate ALK7 as an attractive drug target in human obesity and suggest a lower threshold for ALK7 function in humans compared to mice.


Assuntos
Tecido Adiposo , Obesidade , Humanos , Camundongos , Animais , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Lipólise/genética , Distribuição da Gordura Corporal , Dieta Hiperlipídica/efeitos adversos , Receptores de Ativinas Tipo I/genética , Receptores de Ativinas Tipo I/metabolismo
13.
J Colloid Interface Sci ; 663: 856-868, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447400

RESUMO

Mitochondrial dysfunction and metal ion imbalance are recognized as pathological hallmarks of Alzheimer's Disease (AD), leading to deposition of ß-amyloid (Aß) thereby and inducing neurotoxicity, activating apoptosis, eliciting oxidative stress, and ultimately leading to cognitive impairment. In this study, the red blood cell membrane (RBC) was used as a vehicle for encapsulating carbon quantum dots (CQD) and polydopamine (PDA), creating a nanocomposite (PDA-CQD/RBC). This nanocomposite was combined with near-infrared light (NIR) for AD treatment. The RBC offers anti-immunorecognition properties to evade immune clearance, PDA exhibits enzyme-mimicking activity to mitigate oxidative stress damage, and CQD acts as a chelating agent for metal ions (Cu2+), effectively preventing Cu2+-mediated aggregation of Aß. Furthermore, the local heating induced by near-infrared laser irradiation can dismantle the formed Aß fibers and enhance the blood-brain barrier's permeability. Both in vitro and animal experiments have shown that PDA-CQD/RBC, in combination with NIR, mitigates neuroinflammation, and ameliorates behavioral deficits in mice. This approach targets multiple pathological pathways, surpassing the limitations of single-target treatments and enhancing therapeutic efficacy while decelerating disease progression.


Assuntos
Doença de Alzheimer , Indóis , Polímeros , Pontos Quânticos , Camundongos , Animais , Doença de Alzheimer/tratamento farmacológico , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/patologia , Peptídeos beta-Amiloides , Metais , Raios Infravermelhos , Carbono/farmacologia
14.
Chemosphere ; 358: 142277, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719118

RESUMO

Peracetic acid (PAA) has garnered significant attention as a novel disinfectant owing to its remarkable oxidative capacity and minimal potential to generate byproducts. In this study, we prepared a novel catalyst, denoted as cobalt modified nitrogen-doped carbon nanotubes (Co@N-CNTs), and evaluated it for PAA activation. Modification with cobalt nanoparticles (∼4.8 nm) changed the morphology and structure of the carbon nanotubes, and greatly improved their ability to activate PAA. Co@N-CNTs/PAA catalytic system shows outstanding catalytic degradation ability of antiviral drugs. Under neutral conditions, with a dosage of 0.05 g/L Co@N-CNT-9.8 and 0.25 mM PAA, the removal efficiency of acyclovir (ACV) reached 98.3% within a mere 10 min. The primary reactive species responsible for effective pollutant degradation were identified as acetylperoxyl radicals (CH3C(O)OO•) and acetyloxyl radicals (CH3C(O)O•). In addition, density functional theory (DFT) proved that Co nanoparticles, as the main catalytic sites, were more likely to adsorb PAA and transfer more electrons than N-doped graphene. This study explored the feasibility of PAA degradation of antiviral drugs in sewage, and provided new insights for the application of heterogeneous catalytic PAA in environmental remediation.


Assuntos
Antivirais , Cobalto , Nanotubos de Carbono , Nitrogênio , Ácido Peracético , Nanotubos de Carbono/química , Nitrogênio/química , Cobalto/química , Ácido Peracético/química , Catálise , Antivirais/química , Poluentes Químicos da Água/química , Aciclovir/química , Adsorção
15.
Front Oncol ; 14: 1386772, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737903

RESUMO

Tumor vasculature is pivotal in regulating tumor perfusion, immune cell infiltration, metastasis, and invasion. The vascular status of the tumor is intricately linked to its immune landscape and response to immunotherapy. Vessel co-option means that tumor tissue adeptly exploits pre-existing blood vessels in the para-carcinoma region to foster its growth rather than inducing angiogenesis. It emerges as a significant mechanism contributing to anti-angiogenic therapy resistance. Different from angiogenic tumors, vessel co-option presents a distinctive vascular-immune niche characterized by varying states and distribution of immune cells, including T-cells, tumor-associated macrophages, neutrophils, and hepatic stellate cells. This unique composition contributes to an immunosuppressive tumor microenvironment that is crucial in modulating the response to cancer immunotherapy. In this review, we systematically reviewed the evidence and molecular mechanisms of vessel co-option in liver cancer, while also exploring its implications for anti-angiogenic drug resistance and the immune microenvironment, to provide new ideas and clues for screening patients with liver cancer who are effective in immunotherapy.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38984582

RESUMO

OBJECTIVE: Proteomic elucidation is an essential step in improving our understanding of the biological properties of proteins in amyotrophic lateral sclerosis (ALS). METHODS: Preliminary proteomic analysis was performed on the spinal cord and brain of SOD1 G93A (TG) and wild-type (WT) mice using isobaric tags for relative and absolute quantitation. RESULTS: Partial up- and downregulated proteins showing significant differences between TG and WT mice were identified, of which 105 proteins overlapped with differentially expressed proteins in both the spinal cord and brain of progression mice. Bioinformatic analyses using Gene Ontology, a cluster of orthologous groups, and Kyoto Encyclopedia of Genes and Genomes pathway revealed that the significantly up- and downregulated proteins represented multiple biological functions closely related to ALS, with 105 overlapping differentially expressed proteins in the spinal cord and brain at the progression stage of TG mice closely related to 122 pathways. Differentially expressed proteins involved in a set of molecular functions play essential roles in maintaining neural cell survival. CONCLUSION: This study provides additional proteomic profiles of TG mice, including potential overlapping proteins in both the spinal cord and brain that participate in pathogenesis, as well as novel insights into the up- and downregulation of proteins involved in the pathogenesis of ALS.

17.
ACS Appl Mater Interfaces ; 16(28): 35898-35911, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38954799

RESUMO

Alzheimer's disease (AD) has a complex etiology and diverse pathological processes. The therapeutic effect of single-target drugs is limited, so simultaneous intervention of multiple targets is gradually becoming a new research trend. Critical stages in AD progression involve amyloid-ß (Aß) self-aggregation, metal-ion-triggered fibril formation, and elevated reactive oxygen species (ROS). Herein, red blood cell membranes (RBC) are used as templates for the in situ growth of cerium oxide (CeO2) nanocrystals. Then, carbon quantum dots (CQDs) are encapsulated to form nanocomposites (CQD-Ce-RBC). This strategy is combined with photothermal therapy (PTT) for AD therapy. The application of RBC enhances the materials' biocompatibility and improves immune evasion. RBC-grown CeO2, the first application in the field of AD, demonstrates outstanding antioxidant properties. CQD acts as a chelating agent for copper ions, which prevents the aggregation of Aß. In addition, the thermal effect induced by near-infrared laser-induced CQD can break down Aß fibers and improve the permeability of the blood-brain barrier. In vivo experiments on APP/PS1 mice demonstrate that CQD-Ce-RBC combined with PTT effectively clears cerebral amyloid deposits and significantly enhances learning and cognitive abilities, thereby retarding disease progression. This innovative multipathway approach under light-induced conditions holds promise for AD treatment.


Assuntos
Doença de Alzheimer , Cério , Membrana Eritrocítica , Pontos Quânticos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/terapia , Doença de Alzheimer/metabolismo , Animais , Cério/química , Cério/farmacologia , Camundongos , Membrana Eritrocítica/química , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Humanos , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/química , Raios Infravermelhos , Carbono/química , Carbono/farmacologia , Terapia Fototérmica , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Nanocompostos/química , Nanocompostos/uso terapêutico
18.
Colloids Surf B Biointerfaces ; 238: 113887, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581835

RESUMO

Alzheimer's disease (AD) is complex and multifactorial, and its pathogenesis involves multiple factors and processes. This study pioneered the in situ growth of cerium oxide nanoparticles on macrophage membranes (Ce-RAW). Further, carbon quantum dots (CQD) were biomimetically modified by Ce-RAW, leading to the synthesis of a multifunctional nanocomposite (CQD-Ce-RAW). Within the framework of this research, CQD-Ce-RAW was strategically combined with photothermal therapy (PTT), aiming to achieve a more significant therapeutic effect. The macrophage membrane confers the system with anti-phagocytic and anti-inflammatory biological functions. More importantly, the ultra-small size of cerium oxide grown on the membrane acts as a reactive oxygen species (ROS) scavenger and alleviates the degree of oxidative stress. Meanwhile, CQD as a photosensitizer helps dissociate amyloid-ß (Aß) aggregates and chelates excess copper ions, thus further inhibiting Aß aggregation. Cell experiments showed that CQD-Ce-RAW combined with PTT could effectively degrade and inhibit the aggregation of Aß, remove ROS, and improve cell survival rate. The results of in vivo photothermal experiments demonstrated that near-infrared light enhanced the efficiency of drug penetration through the blood-brain barrier and facilitated its accumulation in brain tissue. This comprehensive therapeutic approach can intervene in the disease progression from multiple pathways, providing a new prospect for treating AD.


Assuntos
Doença de Alzheimer , Biofilmes , Cério , Nanopartículas , Terapia Fototérmica , Espécies Reativas de Oxigênio , Cério/química , Cério/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/terapia , Doença de Alzheimer/patologia , Animais , Camundongos , Nanopartículas/química , Biofilmes/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Pontos Quânticos/química , Peptídeos beta-Amiloides/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Tamanho da Partícula , Células RAW 264.7 , Humanos , Propriedades de Superfície , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos
19.
J Colloid Interface Sci ; 659: 520-532, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38184994

RESUMO

The novel composite photocatalytic material perylene diimides/Fe2O3@C (PDIs/Fe2O3@C) was constructed by a simple hydrothermal-calcination method and an oil bath method. 20 % PDIs/Fe2O3@C displayed a 16.4-fold increase in the rate of tetracycline (TC) removal over Fe2O3@C at 8 min. The main factor that enhanced photocatalytic performance was due to the combination of PDIs with Fe2O3@C, which effectively improved the phenomenon during the self-assembly of highly agglomerative PDIs, increased the specific surface area of Fe2O3@C, exposed more reaction sites, and promoted the activation of peroxymonosulfate (PMS) by Fe2+/Fe3+; and secondly, the composite of two different materials, both organic and inorganic, which effectively promoted the photogenerated electron transfer and the separation of electron-hole pairs, the a new S-scheme electron transport pathway is formed, which effectively promoted the photogenerated electron transfer as well as the e--h+ separation, which was more favorable for the activation of PMS. The whole reaction pathway and product toxicity were thoroughly evaluated by Fukui function calculations, Liquid Chromatograph Mass Spectrometer (LC-MS), and Toxicity Estimation Software Tool (T.E.S.T.) simulation results, which demonstrated the rationality of the degradation pathway and the greatly reduced product toxicity. Moreover, the composites were effective and versatile for all other antibiotics (chlortetracycline (CTC), ciprofloxacin (CIP) and sulfadiazine (SDZ)). As an advanced oxidation process, the activation of PDIs/Fe2O3@C under visible light shows its potential application in pollutant degradation, which provides new perspectives and ideas for further effective treatment of real wastewater.


Assuntos
Antibacterianos , Peróxidos , Perileno , Antibacterianos/farmacologia , Elétrons , Luz
20.
ACS Appl Mater Interfaces ; 16(4): 4934-4947, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38252808

RESUMO

Dielectric ceramics with ultrahigh polarization and energy density are the core components used in next-generation pulse power generators based on explosive energy conversion. However, the low polarization of ferroelectric materials and high depolarized pressure hinder their development toward miniaturization, light weight, and integration, while antiferroelectric materials possessing larger nonlinear saturated polarization and rich phase structure are neglected in pulse power energy conversion. Here, an effective strategy of constructing antiferroelectric-to-ferroelectric overlap zone is achieved in binary system (1 - x)(Pb,La)(Zr,Ti)O3-xBa(Al1/2Nb1/2)O3 antiferroelectric ceramics to realize an excellent polarization of 41 µC/cm2 and a large depolarization efficiency of >99% under 150 MPa as well as a record high energy harvesting density of 2.5 J/cm3 under 400 MPa. The excellent comprehensive energy conversion and energy harvesting performance is mainly attributed to the strategy of antiferroelectric-to-ferroelectric overlap zone and improved microdomain density, at which orthorhombic-to-rhombohedral structure evolution is confirmed by transmission electron microscopy, piezo-response force microscopy, and Raman spectrum, resulting in substantially enhanced remanent polarization compared to ferroelectric ceramics. Besides, excellent temperature stability (∼180 °C) and optimized depolarization pressure also support that this binary system is a candidate for energy conversion and energy harvesting application. This work demonstrates that antiferroelectric-to-ferroelectric overlap based on antiferroelectric materials is an excellent strategy to develop dielectric materials with excellent depolarized polarization and energy harvesting density for energy conversion and harvesting.

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