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1.
Adv Sci (Weinh) ; 11(18): e2307269, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38445899

RESUMO

Surface modification is an important approach to improve osseointegration of the endosseous implants, however it is still desirable to develop a facile yet efficient coating strategy. Herein, a metal-phenolic network (MPN) is proposed as a multifunctional nanocoating on titanium (Ti) implants for enhanced osseointegration through early immunomodulation. With tannic acid (TA) and Sr2+ self-assembled on Ti substrates, the MPN coatings provided a bioactive interface, which can facilitate the initial adhesion and recruitment of bone marrow mesenchymal stem cells (BMSCs) and polarize macrophage toward M2 phenotype. Furthermore, the TA-Sr coatings accelerated the osteogenic differentiation of BMSCs. In vivo evaluations further confirmed the enhanced osseointegration of TA-Sr modified implants via generating a favorable osteoimmune microenvironment. In general, these results suggest that TA-Sr MPN nanocoating is a promising strategy for achieving better and faster osseointegration of bone implants, which can be easily utilized in future clinical applications.


Assuntos
Imunomodulação , Células-Tronco Mesenquimais , Osseointegração , Titânio , Osseointegração/efeitos dos fármacos , Animais , Titânio/química , Imunomodulação/efeitos dos fármacos , Taninos/farmacologia , Taninos/química , Propriedades de Superfície , Próteses e Implantes , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Osteogênese/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Camundongos , Estrôncio/química , Estrôncio/farmacologia , Modelos Animais , Ratos
2.
Eur J Pharmacol ; 971: 176519, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38522641

RESUMO

Aberrant lipid metabolism impacts intratumoral T cell-mediated immune response and tumor growth. Fatostatin functions as an inhibitor of sterol regulatory element binding protein (SREBP) activation. However, the complex effects of fatostatin on cholesterol metabolism in the tumor microenvironment (TME) and its influence on T cell anti-tumor immunity remain unclear. In this study, fatostatin effectively suppressed B16 melanoma, MC38 colon cancer, and Lewis lung cancer (LLC) transplanted tumor growth in immunocompetent mice by reducing SREBPs-mediated lipid metabolism, especially cholesterol levels. Mechanistically, fatostatin decreased intracellular cholesterol accumulation and inhibited X-box binding protein 1 (XBP1)-mediated endoplasmic reticulum (ER) stress, reducing Treg cells and alleviating CD8+ T cell exhaustion in the TME, exerting anti-tumor activity. Nevertheless, this effect was impaired in immunodeficient nude mice, suggesting fatostatin's anti-tumor efficacy in transplanted tumors partly relies on T cell-mediated anti-tumor immunity. Our study highlights SREBP2-mediated cholesterol metabolism as a potential strategy for anti-tumor immunotherapy, and confirms fatostatin's promise in tumor immunotherapy.


Assuntos
Melanoma Experimental , Piridinas , Tiazóis , Animais , Camundongos , Camundongos Nus , Melanoma Experimental/tratamento farmacológico , Metabolismo dos Lipídeos , Colesterol/metabolismo , Microambiente Tumoral
3.
Chem Biol Interact ; 385: 110739, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37805176

RESUMO

Allergy is a growing global public health problem with a high socio-economic impact. The incidence of allergic diseases is increasing year by year, which has attracted more and more attention. In recent years, a number of epidemiological investigations and gut microbiota studies have shown that gut microbiota dysbiosis is associated with an increased prevalence of various allergic diseases, such as food allergy, asthma, allergic rhinitis, and atopic dermatitis. However, the underlying mechanisms are complex and have not been fully clarified. Metabolites are one of the main ways in which the gut microbiota functions. Short-chain fatty acids (SCFAs) are the main metabolites of intestinal flora fermentation and are beneficial to human health. Studies have shown that SCFAs play an important role in maintaining intestinal homeostasis and regulating immune responses by recognizing receptors and inhibiting histone deacetylases, and are key molecules involved in the occurrence and development of allergic diseases. In addition, research on the regulation of gut microbiota and the application of SCFAs in the treatment of allergic diseases is also emerging. This article reviews the clinical and experimental evidence on the correlation between SCFAs and allergic diseases and the potential mechanisms by which SCFAs regulate allergic diseases. Furthermore, SCFAs as therapeutic targets for allergic diseases are also summarized and prospected.


Assuntos
Asma , Dermatite Atópica , Microbioma Gastrointestinal , Hipersensibilidade , Humanos , Ácidos Graxos Voláteis/metabolismo , Hipersensibilidade/complicações , Dermatite Atópica/complicações
4.
Front Genet ; 14: 1231415, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37867602

RESUMO

Stomach Adenocarcinoma (STAD) is a leading cause of death worldwide. Somatic Copy Number Alterations (SCNAs), which result in Homologous recombination (HR) deficiency in double-strand break repair, are associated with the progression of STAD. However, the landscape of frequent breakpoints of SCNAs (hotspots) and their functional impacts remain poorly understood. In this study, we aimed to explore the frequency and impact of these hotspots in 332 STAD patients and 1,043 cancer cells using data from the Cancer Genome Atlas (TCGA) and Cancer Cell Line Encyclopedia (CCLE). We studied the rates of DSB (Double-Strand Breaks) loci in STAD patients by employing the Non-Homogeneous Poisson Distribution (λ), based on which we identified 145 DSB-hotspots with genes affected. We further verified DNA cytosine deamination as a critical process underlying the burden of DSB in STAD. Finally, we illustrated the clinical impact of the significant biological processes. Our findings highlighted the relationship between DNA cytosine deamination and SCNA in cancer was associated with recurrent Somatic Copy Number Alterations in STAD.

5.
Environ Sci Pollut Res Int ; 30(26): 68403-68416, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37121944

RESUMO

Multilayer strontium-doped TiO2/carbon dots (CDs) materials (TC) were produced via sol-gel-layered carbonization method. A thorough analysis of the fabricated composites via XRD, SEM, and XPS revealed that strontium ions, TiO2 and CDs, were combined with each other to form layered structures. According to the UV-Vis diffuse reflectance spectrograms and (αhv)1/2 vs. hv plots, the electron-donor property of strontium ions caused a more positive TC conduction band position than that in the pure TiO2, thereby increasing the visible-light absorption range of TC. Based on the photocatalytic degradation data, the degradation rate of enrofloxacin was 84.7% at the dosage of 0.05 g·L-1 and the concentration of 10 mg·L-1. The capture experiments and ESR results showed that ·O2- and e- played a major role in the degradation process of TC. The possible degradation mechanism of enrofloxacin was explained in terms of decarboxylation and defluorination, as was detected via ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) analysis.


Assuntos
Carbono , Espectrometria de Massas em Tandem , Enrofloxacina , Cromatografia Líquida , Luz , Titânio/química , Catálise
7.
Int J Oral Sci ; 14(1): 48, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36216801

RESUMO

Maintaining the stemness of the transplanted stem cell spheroids in an inflammatory microenvironment is challenging but important in regenerative medicine. Direct delivery of stem cells to repair periodontal defects may yield suboptimal effects due to the complexity of the periodontal inflammatory environment. Herein, stem cell spheroid is encapsulated by interfacial assembly of metal-phenolic network (MPN) nanofilm to form a stem cell microsphere capsule. Specifically, periodontal ligament stem cells (PDLSCs) spheroid was coated with FeIII/tannic acid coordination network to obtain spheroid@[FeIII-TA] microcapsules. The formed biodegradable MPN biointerface acted as a cytoprotective barrier and exhibited antioxidative, antibacterial and anti-inflammatory activities, effectively remodeling the inflammatory microenvironment and maintaining the stemness of PDLSCs. The stem cell microencapsulation proposed in this study can be applied to multiple stem cells with various functional metal ion/polyphenol coordination, providing a simple yet efficient delivery strategy for stem cell stemness maintenance in an inflammatory environment toward a better therapeutic outcome.


Assuntos
Encapsulamento de Células , Polifenóis , Antibacterianos/farmacologia , Cápsulas/farmacologia , Diferenciação Celular , Células Cultivadas , Compostos Férricos/farmacologia , Osteogênese/fisiologia , Ligamento Periodontal , Polifenóis/farmacologia , Células-Tronco , Taninos/farmacologia
8.
Front Nutr ; 9: 992487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967800

RESUMO

[This corrects the article DOI: 10.3389/fnut.2022.928972.].

9.
Front Nutr ; 9: 928972, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35799594

RESUMO

Sesame seed hull is the major by-product of sesame seed processing and is rich in polysaccharides. In this work, sesame hull polysaccharides (SHP) were extracted by ultrasound-assisted alkali extraction methods with a yield of 6.49%. Three purified polysaccharide fractions were obtained after decolorization, deproteinization, and column chromatography. Then, their main composition and antioxidant activity were investigated. The dominant fraction was SHP-2 with a yield of 3.78%. It was composed of galacturonic acid (51.3%), glucuronic acid (13.8%), rhamnose (8.9%), glucose (8.4%), and others. The linkage types of SHP-2 have the α-D-GalpA-(1,4)-linked, α-D-GlcpA-(1,2)-linked, ß-T-D-Rhap-linked, ß-D-Glcp-(1,6)-linked, ß-T-D-Galp-linked, α-L-Xylp-(1,4)-linked, α-L-Araf-(1,3,5)-linked, and ß-D-Manp-(1,4)-linked. This study might provide some useful basic data for developing applications for sesame seed hull polysaccharides in the food and pharmaceutical industries.

10.
Front Bioeng Biotechnol ; 10: 916967, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35837554

RESUMO

Sufficient bone volume is indispensable to achieve functional and aesthetic results in the fields of oral oncology, trauma, and implantology. Currently, guided bone regeneration (GBR) is widely used in reconstructing the alveolar ridge and repairing bone defects owing to its low technical sensitivity and considerable osteogenic effect. However, traditional barrier membranes such as collagen membranes or commercial titanium mesh cannot meet clinical requirements, such as lack of space-preserving ability, or may lead to more complications. With the development of digitalization and three-dimensional printing technology, the above problems can be addressed by employing customized barrier membranes to achieve space maintenance, precise predictability of bone graft, and optimization of patient-specific strategies. The article reviews the processes and advantages of three-dimensional computer-assisted surgery with GBR in maxillofacial reconstruction and alveolar bone augmentation; the properties of materials used in fabricating customized bone regeneration sheets; the promising bone regeneration potency of customized barrier membranes in clinical applications; and up-to-date achievements. This review aims to present a reference on the clinical aspects and future applications of customized barrier membranes.

11.
Nutrition ; 101: 111703, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35700592

RESUMO

OBJECTIVES: Coenzyme Q10 (CoQ10) had shown promising effects in improving the lipid and glycemic profile in dyslipidemic individuals in our previous work, but little is known about how it affects high-density lipoprotein (HDL) function in patients with dyslipidemia. The aim of this study was to explore the effects of CoQ10 supplementation on HDL function in people with dyslipidemia. METHODS: A 24-wk, randomized, double-blind, placebo-controlled trial was conducted in 101 people with dyslipidemia. All patients were randomized into the CoQ10 group (120 mg/d, n = 51) or the placebo group (n = 50). High-density lipoprotein-mediated cholesterol efflux capacity (CEC), HDL inflammatory index (HII), and HDL intrinsic oxidation were measured at baseline, 12 wk, and 24 wk. RESULTS: CoQ10 supplementation for 24 wk significantly improved HDL-mediated CEC (mean change, 1.21±2.44 versus -0.12±2.94; P = 0.014) and reduced HII (mean change, -0.32±0.58 versus -0.05±0.49, P = 0.014) compared with placebo. However, there was no significant difference in the effect of CoQ10 on HDL intrinsic oxidation between the two groups after 24 wk (P = 0.290). A positive correlation was found between the changes in CEC and HDL cholesterol in the CoQ10 group (r, 0.30; P = 0.032). Furthermore, we also found that the improved HDL functions were more obvious in elderly, female, or non-obese individuals, which indicated a specific population that benefits most from CoQ10 intervention. CONCLUSIONS: This study suggested that supplementation of CoQ10 for 24 wk can significantly improve HDL-mediated CEC and antiinflammatory function of HDL in patients with dyslipidemia.


Assuntos
Dislipidemias , Lipoproteínas HDL , Adulto , Idoso , China , HDL-Colesterol , Suplementos Nutricionais , Método Duplo-Cego , Dislipidemias/tratamento farmacológico , Feminino , Humanos , Ubiquinona/análogos & derivados , Ubiquinona/farmacologia , Ubiquinona/uso terapêutico
12.
Sci Total Environ ; 829: 154519, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35292317

RESUMO

Large airport operation release harmful air pollutants and have adverse impact on local air quality. As one of the world's top 30 busiest airports, Xinzheng International Airport (CGO) located in Zhengzhou City, China, its emission impacts needs particular attention. To identify the possible impacts and quantify the contribution of CGO airport to air pollution, a comprehensive approach including emission inventory, continuous monitoring, coupled with statistical modelling was adopted in this study. We estimated a more detailed emissions inventory for CGO, including hourly and annual emissions from engines and auxiliary power units of aircrafts during landing and take-off flight, and airside ground support equipment (GSE) in 2019. The results indicate that almost all the CGO specific parameters including operating hours, fuel consumption and unit LTO emissions at different modes were lower than ICAO reference values. The annual total emissions of NOx, CO, HC, SO2 and PM from CGO from aircrafts and GSE were 1207.7, 921.3, 123.7, 268.3 and 36.2 tons, respectively. In addition to SO2, the main engines of the aircraft accounted for 80.3%, 62.6%, 45.5% and 74.3% of the total emissions, respectively. Meanwhile, a continuous monitoring campaign was conducted for one year in the vicinity of CGO airport. The monitoring data were analyzed using generalized additive model (GAM) to quantify the impact of NOx emissions from airport activities on air quality at CGO. The results showed that even the influence of environmental and meteorological variables was greater, nearly 13% of the ambient NOx concentrations were explained by emissions from airport activities, indicating the importance of airport-related emissions as the major source affecting local air quality.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Aeroportos , China , Monitoramento Ambiental , Material Particulado/análise , Emissões de Veículos/análise
13.
EBioMedicine ; 70: 103533, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34392146

RESUMO

BACKGROUND: Dyslipidemia induces platelet hyperactivation and hyper-aggregation, which are linked to thrombosis. Anthocyanins could inhibit platelet function in vitro and in mice fed high-fat diets with their effects on platelet function in subjects with dyslipidemia remained unknown. This study aimed to investigate the effects of different doses of anthocyanins on platelet function in individuals with dyslipidemia. METHODS: A double-blind, randomized, controlled trial was conducted. Ninety-three individuals who were initially diagnosed with dyslipidemia were randomly assigned to placebo or 40, 80, 160 or 320 mg/day anthocyanin groups. The supplementations were anthocyanin capsules (Medox, Norway). Platelet aggregation by light aggregometry of platelet-rich plasma, P-selectin, activated GPⅡbⅢa, reactive oxygen species (ROS), and mitochondrial membrane potential were tested at baseline, 6 weeks and 12 weeks. FINDINGS: Compared to placebo group, anthocyanins at 80 mg/day for 12 weeks reduced collagen-induced platelet aggregation (-3.39±2.36%) and activated GPⅡbⅢa (-8.25±2.45%) (P < 0.05). Moreover, compared to placebo group, anthocyanins at 320 mg/day inhibited collagen-induced platelet aggregation (-7.05±2.38%), ADP-induced platelet aggregation (-7.14±2.00%), platelet ROS levels (-14.55±1.86%), and mitochondrial membrane potential (7.40±1.56%) (P < 0.05). There were dose-response relationships between anthocyanins and the attenuation of platelet aggregation, mitochondrial membrane potential and ROS levels (P for trend <0.05). Furthermore, significantly positive correlations were observed between changes in collagen-induced (r = 0.473) or ADP-induced (r = 0.551) platelet aggregation and ROS levels in subjects with dyslipidemia after the 12-week intervention (P < 0.05). INTERPRETATION: Anthocyanin supplementation dose-dependently attenuates platelet function, and 12-week supplementation with 80 mg/day or more of anthocyanins can reduce platelet function in individuals with dyslipidemia. FUNDING: None.


Assuntos
Antocianinas/farmacologia , Dislipidemias/tratamento farmacológico , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Adulto , Idoso , Antocianinas/administração & dosagem , Antocianinas/uso terapêutico , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Selectina-P/sangue , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Espécies Reativas de Oxigênio/sangue
14.
Thromb Haemost ; 121(7): 931-943, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33545736

RESUMO

Oxidative stress plays crucial roles in initiating platelet apoptosis that facilitates the progression of cardiovascular diseases (CVDs). Protocatechuic acid (PCA), a major metabolite of anthocyanin cyanidin-3-O-ß-glucoside (Cy-3-g), exerts cardioprotective effects. However, underlying mechanisms responsible for such effects remain unclear. Here, we investigate the effect of PCA on platelet apoptosis and the underlying mechanisms in vitro. Isolated human platelets were treated with hydrogen peroxide (H2O2) to induce apoptosis with or without pretreatment with PCA. We found that PCA dose-dependently inhibited H2O2-induced platelet apoptosis by decreasing the dissipation of mitochondrial membrane potential, activation of caspase-9 and caspase-3, and decreasing phosphatidylserine exposure. Additionally, the distributions of Bax, Bcl-xL, and cytochrome c mediated by H2O2 in the mitochondria and the cytosol were also modulated by PCA treatment. Moreover, the inhibitory effects of PCA on platelet caspase-3 cleavage and phosphatidylserine exposure were mainly mediated by downregulating PI3K/Akt/GSK3ß signaling. Furthermore, PCA dose-dependently decreased reactive oxygen species (ROS) generation and the intracellular Ca2+ concentration in platelets in response to H2O2. N-Acetyl cysteine (NAC), a ROS scavenger, markedly abolished H2O2-stimulated PI3K/Akt/GSK3ß signaling, caspase-3 activation, and phosphatidylserine exposure. The combination of NAC and PCA did not show significant additive inhibitory effects on PI3K/Akt/GSK3ß signaling and platelet apoptosis. Thus, our results suggest that PCA protects platelets from oxidative stress-induced apoptosis through downregulating ROS-mediated PI3K/Akt/GSK3ß signaling, which may be responsible for cardioprotective roles of PCA in CVDs.


Assuntos
Apoptose/efeitos dos fármacos , Doenças Cardiovasculares/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Hidroxibenzoatos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Plaquetas/metabolismo , Cálcio/metabolismo , Catalase/metabolismo , Humanos , Peróxido de Hidrogênio , Camundongos , Camundongos Endogâmicos C57BL , Ativação Plaquetária , Espécies Reativas de Oxigênio , Transdução de Sinais
15.
Food Funct ; 11(1): 139-152, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31755492

RESUMO

Coenzyme Q10 (CoQ10) exists in a wide variety of foods and has promising cardiovascular benefits. However, its effects on platelets and integrin αIIbß3 signaling during atherosclerosis have not been previously explored. Here, apolipoprotein E-deficient (ApoE-/-) mice were fed a standard diet, high-fat diet (HFD) or CoQ10-supplemented HFD for 12 weeks. We found that CoQ10 supplementation in ApoE-/- mice significantly alleviated formation of HFD-induced atherosclerotic lesions, and attenuated platelet hyper-aggregation and granule secretion, including CD62P, CD63 and CD40 ligand (CD40L) expression and platelet factor-4, ß-thromboglobulin and activation normal T cell expressed and secreted (CCL5) release. CoQ10 supplementation decreased soluble fibrinogen and JON/A binding to αIIbß3 on activated platelets, indicating that αIIbß3-mediated inside-out signaling was attenuated. Additionally, CoQ10 down-regulated platelet αIIbß3 outside-in signaling including decreasing phosphorylation of the ß3 intracellular tail, cellular and sarcoma tyrosine-protein kinase (c-Src), and myosin light chain (MLC), and consistently attenuating platelet spreading and clot retraction. Importantly, platelet-monocyte aggregation that was primarily mediated by αIIbß3 and can be blocked using an αIIbß3-specific antagonist tirofiban was also markedly diminished by CoQ10. Thus, CoQ10 supplementation attenuates platelet hyper-reactivity via down-regulating both αIIbß3 inside-out and outside-in signaling, which may play important preventive roles in atherothrombosis.


Assuntos
Aterosclerose/tratamento farmacológico , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ubiquinona/análogos & derivados , Animais , Retração do Coágulo , Masculino , Camundongos , Camundongos Knockout para ApoE , Ubiquinona/uso terapêutico
16.
J Magn Reson ; 308: 106593, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31520789

RESUMO

As a demonstration of the application of rapid-scan EPR to imaging at low frequency and magnetic field, a multi-compartment phantom containing six different samples was imaged. The samples were nitroxide radicals, trityl (substituted triarylmethyl) radicals, and the oxygen-sensitive solid lithium phthalocyanine (LiPc), all of which are useful for in vivo imaging. The 2D spectral-spatial image demonstration was performed at 250 MHz, with samples in sealed tubes of various sizes arranged in a 3D-printed plastic holder. Maximum gradients of 10 G/cm gave a spatial resolution of about 0.1 mm for the narrow trityl and LiPc signals and about 1 mm for the nitroxide. The importance of proper selection of resonator bandwidth and scan rate for obtaining accurate linewidth information is demonstrated for a case in which the phantom is composed of species with signal linewidths and relaxation times that differ by more than a factor of 10.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Campos Eletromagnéticos , Radicais Livres , Indóis/química , Óxidos de Nitrogênio/química , Compostos Organometálicos/química , Trítio , Compostos de Tritil
17.
Mol Nutr Food Res ; 63(23): e1900662, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31512815

RESUMO

SCOPE: Platelet integrin αIIbß3 is the key mediator of atherothrombosis. Supplementation of coenzyme Q10 (CoQ10), a fat-soluble molecule that exists in various foods, exerts protective cardiovascular effects. This study aims to investigate whether and how CoQ10 acts on αIIbß3 signaling and thrombosis, the major cause of cardiovascular diseases. METHODS AND RESULTS: Using a series of platelet functional assays in vitro, it is demonstrated that CoQ10 reduces human platelet aggregation, granule secretion, platelet spreading, and clot retraction. It is further demonstrated that CoQ10 inhibits platelet integrin αIIbß3 outside-in signaling. These inhibitory effects are mainly mediated by upregulating cAMP/PKA pathway, where CoQ10 stimulates the A2A adenosine receptor and decreases phosphodiesterase 3A phosphorylation. Moreover, CoQ10 attenuates murine thrombus growth and vessel occlusion in a ferric chloride (FeCl3 )-induced thrombosis model in vivo. Importantly, the randomized, double-blind, placebo-controlled clinical trial in dyslipidemic patients demonstrates that 24 weeks of CoQ10 supplementation increases platelet CoQ10 concentrations, enhances the cAMP/PKA pathway, and attenuates αIIbß3 outside-in signaling, leading to decreased platelet aggregation and granule release. CONCLUSION: Through upregulating the platelet cAMP/PKA pathway, and attenuating αIIbß3 signaling and thrombus growth, CoQ10 supplementation may play an important protective role in patients with risks of cardiovascular diseases.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , AMP Cíclico/fisiologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/fisiologia , Trombose/prevenção & controle , Ubiquinona/análogos & derivados , Adulto , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Método Duplo-Cego , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Receptor A2A de Adenosina/fisiologia , Transdução de Sinais/fisiologia , Ubiquinona/farmacologia , Regulação para Cima
18.
Appl Magn Reson ; 50(1-3): 333-345, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30799909

RESUMO

A 25 mm diameter 250 MHz crossed-loop resonator was designed for rapid scan electron paramagnetic resonance imaging. It has a saddle coil for the driven resonator and a fine wire, loop gap resonator for the sample resonator. There is good separation of E and B fields and high isolation between the two resonators, permitting a wide range of sample types to be measured. Applications to imaging of nitroxide, trityl, and LiPc samples illustrate the utility of the resonator. Using this resonator and a trityl sample the signal-to-noise of a rapid scan absorption spectrum is about 20 times higher than for a first-derivative CW spectrum.

19.
Adv Exp Med Biol ; 977: 327-334, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28685462

RESUMO

The triarylmethyl radical OX063d24 is currently used for pulsed electron paramagnetic resonance oximetry at 250 MHz. Both 1/T 1 and 1/T 2 increase with increasing oxygen concentration. The dependence of 1/T 1 on probe concentration is smaller than for 1/T 2. To inform the selection of the optimum frequency for in vivo oximetry 1/T 1, 1/T 2 and signal-to-noise were measured as a function of frequency between 400 and 1000 MHz on a variable-frequency spectrometer with an adjustable-frequency cross-loop resonator. 1/T 1 and 1/T 2 decrease with increasing frequency and signal-to-noise increases with increasing frequency, which are all favourable for imaging at higher frequencies. However, depth of penetration of the radio frequency (RF) into an animal decreases with increasing frequency. Assuming that the RF loss in the animal to be studied determines the resonator Q, our results indicate that the optimum frequency for in vivo imaging will be determined by the desired depth of penetration in the tissue.


Assuntos
Elétrons , Oximetria/métodos , Compostos de Sulfidrila/química , Deutério/química , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Indenos/química , Ondas de Rádio , Razão Sinal-Ruído , Compostos de Tritil/química
20.
J Magn Reson ; 280: 140-148, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28579099

RESUMO

In rapid-scan EPR the magnetic field or frequency is repeatedly scanned through the spectrum at rates that are much faster than in conventional continuous wave EPR. The signal is directly-detected with a mixer at the source frequency. Rapid-scan EPR is particularly advantageous when the scan rate through resonance is fast relative to electron spin relaxation rates. In such scans, there may be oscillations on the trailing edge of the spectrum. These oscillations can be removed by mathematical deconvolution to recover the slow-scan absorption spectrum. In cases of inhomogeneous broadening, the oscillations may interfere destructively to the extent that they are not visible. The deconvolution can be used even when it is not required, so spectra can be obtained in which some portions of the spectrum are in the rapid-scan regime and some are not. The technology developed for rapid-scan EPR can be applied generally so long as spectra are obtained in the linear response region. The detection of the full spectrum in each scan, the ability to use higher microwave power without saturation, and the noise filtering inherent in coherent averaging results in substantial improvement in signal-to-noise relative to conventional continuous wave spectroscopy, which is particularly advantageous for low-frequency EPR imaging. This overview describes the principles of rapid-scan EPR and the hardware used to generate the spectra. Examples are provided of its application to imaging of nitroxide radicals, diradicals, and spin-trapped radicals at a Larmor frequency of ca. 250MHz.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Imagem Molecular/métodos , Algoritmos , Animais , Diagnóstico por Imagem , Humanos , Micro-Ondas
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