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1.
Molecules ; 29(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38257230

RESUMO

Hazel leaf, a by-product of hazelnuts, is commonly used in traditional folk medicine in Portugal, Sweden, Iran and other regions for properties such as vascular protection, anti-bleeding, anti-edema, anti-infection, and pain relief. Based on our previous studies, the polyphenol extract from hazel leaf was identified and quantified via HPLC fingerprint. The contents of nine compounds including kaempferol, chlorogenic acid, myricetin, caffeic acid, p-coumaric acid, resveratrol, luteolin, gallic acid and ellagic acid in hazel leaf polyphenol extract (ZP) were preliminary calculated, among which kaempferol was the highest with 221.99 mg/g, followed by chlorogenic acid with 8.23 mg/g. The inhibition of ZP on α-glucosidase and xanthine oxidase activities was determined via the chemical method, and the inhibition on xanthine oxidase was better. Then, the effect of ZP on hyperuricemia zebrafish was investigated. It was found that ZP obviously reduced the levels of uric acid, xanthine oxidase, urea nitrogen and creatinine, and up-regulated the expression ofOAT1 and HPRT genes in hyperuricemia zebrafish. Finally, the targeted network pharmacological analysis and molecular docking of nine polyphenol compounds were performed to search for relevant mechanisms for alleviating hyperuricemia. These results will provide a valuable basis for the development and application of hazel leaf polyphenols as functional ingredients.


Assuntos
Corylus , Hiperuricemia , Animais , Polifenóis/farmacologia , Ácido Clorogênico/farmacologia , Simulação de Acoplamento Molecular , Peixe-Zebra , Farmacologia em Rede , Quempferóis , Hiperuricemia/tratamento farmacológico , Xantina Oxidase , Extratos Vegetais/farmacologia
2.
Molecules ; 29(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675549

RESUMO

Derived from hazelnuts, hazel leaf has been utilized in traditional folk medicine for centuries in countries such as Portugal, Sweden, and Iran. In our previous investigations, we conducted a preliminary assessment of the hazel leaf polyphenol extract (referred to as ZP) and identified nine compounds, such as kaempferol and chlorogenic acid, in its composition. ZP has shown promising properties as an antioxidant and anti-inflammatory agent. Our research has revealed that ZP has protective effects against cisplatin-induced acute kidney injury (AKI). We conducted a comprehensive examination of both the pathological and ultrastructural aspects and found that ZP effectively ameliorated renal tissue lesions and mitigated mitochondrial damage. Moreover, ZP significantly suppressed malondialdehyde levels while increasing glutathione and catalase concentrations in the kidneys of AKI-induced mice. ZP decreased the number of apoptotic cells and decreased pro-apoptotic protein expression in the kidneys of mice and human renal tubular epithelial cells (HK-2). Furthermore, treatment with ZP increased the levels of proteins marking anti-ferroptosis, such as GPX4, FTH1, and FSP1, in experiments both in vivo and in vitro. We elucidated the underlying mechanisms of ZP's actions, revealing its inhibitory effect on Yap phosphorylation and its regulation of Lats expression, which exert a protective influence on the kidneys. Furthermore, we found that inhibiting the Hippo pathway compromised ZP's nephroprotective effects in both in vitro and in vivo studies. In summary, this research shows that ZP exhibits renoprotective properties, effectively reducing oxidative damage, apoptosis, and ferroptosis in the kidneys by targeting the Hippo pathway.


Assuntos
Injúria Renal Aguda , Cisplatino , Ferroptose , Via de Sinalização Hippo , Extratos Vegetais , Folhas de Planta , Polifenóis , Transdução de Sinais , Animais , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/induzido quimicamente , Ferroptose/efeitos dos fármacos , Cisplatino/efeitos adversos , Polifenóis/farmacologia , Polifenóis/química , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Humanos , Transdução de Sinais/efeitos dos fármacos , Folhas de Planta/química , Proteínas Serina-Treonina Quinases/metabolismo , Masculino , Linhagem Celular , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Estresse Oxidativo/efeitos dos fármacos
3.
J Neurochem ; 167(3): 461-484, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37788328

RESUMO

Parkinson's disease (PD) is an age-related chronic neurological disorder, mainly characterized by the pathological feature of α-synuclein (α-syn) aggregation, with the exact disease pathogenesis unclear. During the onset and progression of PD, synaptic dysfunction, including dysregulation of axonal transport, impaired exocytosis, and endocytosis are identified as crucial events of PD pathogenesis. It has been reported that over-expression of α-syn impairs clathrin-mediated endocytosis (CME) in the synapses. However, the underlying mechanisms still needs to be explored. In this study, we investigated the molecular events underlying the synaptic dysfunction caused by over-expression of wild-type human α-syn and its mutant form, involving series of proteins participating in CME. We found that excessive human α-syn causes impaired fission and uncoating of clathrin-coated vesicles during synaptic vesicle recycling, leading to reduced clustering of synaptic vesicles near the active zone and increased size of plasma membrane and number of endocytic intermediates. Furthermore, over-expressed human α-syn induced changes of CME-associated proteins, among which synaptojanin1 (SYNJ1) showed significant reduction in various brain regions. Over-expression of SYNJ1 in primary hippocampal neurons from α-syn transgenic mice recovered the synaptic vesicle density, clustering and endocytosis. Using fluorescence-conjugated transferrin, we demonstrated that SYNJ1 re-boosted the CME activity by restoring the phosphatidylinositol-4,5-bisphosphate homeostasis. Our data suggested that over-expression of α-syn disrupts synaptic function through interfering with vesicle recycling, which could be alleviated by re-availing of SYNJ1. Our study unrevealed a molecular mechanism of the synaptic dysfunction in PD pathogenesis and provided a potential therapeutic target for treating PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Humanos , Camundongos , alfa-Sinucleína/metabolismo , Clatrina/metabolismo , Endocitose/fisiologia , Camundongos Transgênicos , Doença de Parkinson/metabolismo , Sinapses/metabolismo
4.
J Sep Sci ; 46(10): e2300029, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36880199

RESUMO

Efficient strategies for the preparative separation of iridoid glycosides and flavonoid glycosides from Hedyotis diffusa using preparative high-performance liquid chromatography combined with appropriate pretreatment technologies were developed. Four fractions (Fr.1-1, Fr.1-2, Fr.1-3, and Fr.2-1) were firstly isolated from the crude extract of Hedyotis diffusa by column chromatography with C18, resin, and silica gel materials, respectively. Then, corresponding separation strategies were developed according to the polarity and chemical constituents. High-polar compounds of Fr.1-1 were purified by hydrophilic reversed-phase liquid chromatography and hydrophilic interaction liquid chromatography mode. The combination of C18 and phenyl columns realized the complementary separation of iridoid glycosides in Fr.1-2. Meanwhile, the improved selectivity caused by the change of organic solvent in the mobile phase was utilized to realize the purification of flavonoid glycosides in Fr.1-3 and Fr. 2-1. Finally, 27 compounds (purity > 95%) mainly involving nine iridoid glycosides and five flavonoid glycosides were obtained. A complete strategy was established for the separation of a complex sample with a wide polarity range, to jointly solve the problems of enrichment of target components and separation of structural analogs.


Assuntos
Glicosídeos , Hedyotis , Glicosídeos Iridoides/química , Flavonoides/análise , Hedyotis/química , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão/métodos
5.
J Clin Apher ; 36(4): 634-644, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34046928

RESUMO

BACKGROUND: Whether race/ethnicity plays a role in hematopoietic stem/progenitor cells (HSPC) mobilization in autologous donors has not been studied. We hypothesize that donor characteristic including race/ethnicity, age, sex, body mass index, and diagnostic groups influences HSPC mobilization. Diagnostic groups include healthy allogeneic donors, autologous multiple myeloma (MM) and non-MM donors. STUDY DESIGN AND METHODS: Here, we conducted a single-center retrospective study in 64 autologous patients and 48 allogeneic donors. Autologous donors were patients diagnosed with MM or non-MM. All donors were grouped as African American (AA), White (W), or "Other"(O). RESULTS: Multivariate analysis demonstrated diagnostic group differences for CD34+ cell yields between race/ethnicity. Specifically, non-MM patients had the lowest CD34+ cell yields in AA and O, but not in W. For pre-apheresis peripheral blood (PB) CD34+ cell numbers, race/ethnicity had a significant effect both in bivariate and multivariate analyses. Non-MM patients had the lowest, and AA patients had the highest PB CD34+ cells. The results support the view that past therapies used in MM are likely more conducive of recovery of HSPC. CONCLUSIONS: Our study shows that race/ethnicity and diagnostic group differences influenced CD34+ cell mobilization response across donor types. Interestingly, autologous MM donors with the aid of plerixafor displayed comparable CD34 yields to allogeneic donors. Even though both MM and non-MM donors received plerixafor, non-MM donors had significantly lower CD34 yields among AA and O donors but not in W donors. Larger studies would be required to validate the role of diagnostic groups and race/ethnicity interactions.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Mieloma Múltiplo/etnologia , Mieloma Múltiplo/terapia , Células-Tronco/citologia , Adulto , Negro ou Afro-Americano , Idoso , Antígenos CD34/metabolismo , Remoção de Componentes Sanguíneos , Índice de Massa Corporal , Etnicidade , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Transplante Autólogo , Transplante Homólogo , Estados Unidos
6.
PLoS Pathog ; 13(7): e1006491, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28704563

RESUMO

Prions, characterized by self-propagating protease-resistant prion protein (PrP) conformations, are agents causing prion disease. Recent studies generated several such self-propagating protease-resistant recombinant PrP (rPrP-res) conformers. While some cause prion disease, others fail to induce any pathology. Here we showed that although distinctly different, the pathogenic and non-pathogenic rPrP-res conformers were similarly recognized by a group of conformational antibodies against prions and shared a similar guanidine hydrochloride denaturation profile, suggesting a similar overall architecture. Interestingly, two independently generated non-pathogenic rPrP-res were almost identical, indicating that the particular rPrP-res resulted from cofactor-guided PrP misfolding, rather than stochastic PrP aggregation. Consistent with the notion that cofactors influence rPrP-res conformation, the propagation of all rPrP-res formed with phosphatidylglycerol/RNA was cofactor-dependent, which is different from rPrP-res generated with a single cofactor, phosphatidylethanolamine. Unexpectedly, despite the dramatic difference in disease-causing capability, RT-QuIC assays detected large increases in seeding activity in both pathogenic and non-pathogenic rPrP-res inoculated mice, indicating that the non-pathogenic rPrP-res is not completely inert in vivo. Together, our study supported a role of cofactors in guiding PrP misfolding, indicated that relatively small structural features determine rPrP-res' pathogenicity, and revealed that the in vivo seeding ability of rPrP-res does not necessarily result in pathogenicity.


Assuntos
Endopeptidases/química , Doenças Priônicas/metabolismo , Proteínas Priônicas/química , Animais , Biocatálise , Dimerização , Endopeptidases/metabolismo , Camundongos , Fosfatidilgliceróis/metabolismo , Doenças Priônicas/genética , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , Ligação Proteica , Conformação Proteica , RNA/química , RNA/genética , RNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Mol Cell Biochem ; 445(1-2): 25-33, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29260433

RESUMO

Choroidal melanoma is the most common intraocular tumor in adults, and overexpression of matrix metalloproteinase-2 or matrix metalloproteinase-9 (MMP-2/MMP-9) is associated with angiogenesis and tumor metastasis of the choroidal malignant melanoma (CMM). This study aims to investigate the functions and mechanisms of microRNA or long non-coding RNA-targeted MMP-2/MMP-9 in CMM. We demonstrated that expressions of MMP-2/MMP-9 were increased in CMM tissues and C918 cells in comparison with normal choroidal melanocytes. Bio-informatics prediction and our experiments validated that MMP-2 and MMP-9 were simultaneously targeted by miR-296-3p and FOXC1 promoter upstream transcript (FOXCUT); the latter two exerted tumor-suppressing effects on CMM cells by inhibiting cell proliferation, cell cycle progression, migration, invasion, and induction of cell apoptosis. Furthermore, significant downregulations of miR-296-3p and FOXCUT were found in C918 cells compared with choroidal melanocytes from the unaffected eyes, and a positive correlation was observed between their levels in three cases of eye malignant melanomas. Our data indicated that MMP-2/MMP-9 was coordinately targeted by two non-coding RNAs, miR-296-3p and FOXCUT, which were decreased, and tumor-suppressing factors in CMM. Further study will show the possibility of developing them as therapeutic candidates for CMM.


Assuntos
Neoplasias da Coroide/patologia , Genes Supressores de Tumor , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Melanoma/patologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Células Cultivadas , Neoplasias da Coroide/enzimologia , Neoplasias da Coroide/genética , Regulação para Baixo , Humanos , Melanoma/enzimologia , Melanoma/genética , MicroRNAs/genética , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , RNA Longo não Codificante/genética , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
8.
Nano Lett ; 17(2): 915-921, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28068098

RESUMO

Phonon-cavity electromechanics allows the manipulation of mechanical oscillations similar to photon-cavity systems. Many advances on this subject have been achieved in various materials. In addition, the coherent phonon transfer (phonon Rabi oscillations) between the phonon cavity mode and another oscillation mode has attracted many interest in nanoscience. Here, we demonstrate coherent phonon transfer in a carbon nanotube phonon-cavity system with two mechanical modes exhibiting strong dynamical coupling. The gate-tunable phonon oscillation modes are manipulated and detected by extending the red-detuned pump idea of photonic cavity electromechanics. The first- and second-order coherent phonon transfers are observed with Rabi frequencies 591 and 125 kHz, respectively. The frequency quality factor product fQm ∼ 2 × 1012 Hz achieved here is larger than kBTbase/h, which may enable the future realization of Rabi oscillations in the quantum regime.

9.
PLoS Pathog ; 11(7): e1004958, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26136122

RESUMO

The prion hypothesis postulates that the infectious agent in transmissible spongiform encephalopathies (TSEs) is an unorthodox protein conformation based agent. Recent successes in generating mammalian prions in vitro with bacterially expressed recombinant prion protein provide strong support for the hypothesis. However, whether the pathogenic properties of synthetically generated prion (rec-Prion) recapitulate those of naturally occurring prions remains unresolved. Using end-point titration assay, we showed that the in vitro prepared rec-Prions have infectious titers of around 104 LD50/µg. In addition, intraperitoneal (i.p.) inoculation of wild-type mice with rec-Prion caused prion disease with an average survival time of 210-220 days post inoculation. Detailed pathological analyses revealed that the nature of rec-Prion induced lesions, including spongiform change, disease specific prion protein accumulation (PrP-d) and the PrP-d dissemination amongst lymphoid and peripheral nervous system tissues, the route and mechanisms of neuroinvasion were all typical of classical rodent prions. Our results revealed that, similar to naturally occurring prions, the rec-Prion has a titratable infectivity and is capable of causing prion disease via routes other than direct intra-cerebral challenge. More importantly, our results established that the rec-Prion caused disease is pathogenically and pathologically identical to naturally occurring contagious TSEs, supporting the concept that a conformationally altered protein agent is responsible for the infectivity in TSEs.


Assuntos
Modelos Animais de Doenças , Doenças Priônicas/patologia , Príons/patogenicidade , Proteínas Recombinantes/administração & dosagem , Animais , Imuno-Histoquímica , Injeções Intraperitoneais , Camundongos , Príons/administração & dosagem , Proteínas Recombinantes/síntese química
10.
Nano Lett ; 16(9): 5456-62, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27487412

RESUMO

Coupling an electromechanical resonator with carbon-nanotube quantum dots is a significant method to control both the electronic charge and the spin quantum states. By exploiting a novel microtransfer technique, we fabricate two separate strongly coupled and electrically tunable mechanical resonators for the first time. The frequency of the two resonators can be individually tuned by the bottom gates, and in each resonator, the electron transport through the quantum dot can be strongly affected by the phonon mode and vice versa. Furthermore, the conductance of either resonator can be nonlocally modulated by the other resonator through phonon-phonon interaction between the two resonators. Strong coupling is observed between the phonon modes of the two resonators, where the coupling strength larger than 200 kHz can be reached. This strongly coupled nanotube electromechanical resonator array provides an experimental platform for future studies of the coherent electron-phonon interaction, the phonon-mediated long-distance electron interaction, and entanglement state generation.

11.
Proc Natl Acad Sci U S A ; 109(28): E1938-46, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22711839

RESUMO

Prions containing misfolded prion protein (PrP(Sc)) can be formed with cofactor molecules using the technique of serial protein misfolding cyclic amplification. However, it remains unknown whether cofactors materially participate in maintaining prion conformation and infectious properties. Here we show that withdrawal of cofactor molecules during serial propagation of purified recombinant prions caused adaptation of PrP(Sc) structure accompanied by a reduction in specific infectivity of >10(5)-fold, to undetectable levels, despite the ability of adapted "protein-only" PrP(Sc) molecules to self-propagate in vitro. We also report that changing only the cofactor component of a minimal reaction substrate mixture during serial propagation induced major changes in the strain properties of an infectious recombinant prion. Moreover, propagation with only one functional cofactor (phosphatidylethanolamine) induced the conversion of three distinct strains into a single strain with unique infectious properties and PrP(Sc) structure. Taken together, these results indicate that cofactor molecules can regulate the defining features of mammalian prions: PrP(Sc) conformation, infectivity, and strain properties. These findings suggest that cofactor molecules likely are integral components of infectious prions.


Assuntos
Príons/química , Animais , Catálise , Feminino , Glicosilação , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Força Atômica/métodos , Fosfatidiletanolaminas/química , Príons/metabolismo , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Proteínas Recombinantes/química , Ureia/química
12.
FASEB J ; 27(12): 4768-75, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23970796

RESUMO

The prion hypothesis is strongly supported by the fact that prion infectivity and the pathogenic conformer of prion protein (PrP) are simultaneously propagated in vitro by the serial protein misfolding cyclic amplification (sPMCA). However, due to sPMCA's enormous amplification power, whether an infectious prion can be formed de novo with bacterially expressed recombinant PrP (rPrP) remains to be satisfactorily resolved. To address this question, we performed unseeded sPMCA with rPrP in a laboratory that has never been exposed to any native prions. Two types of proteinase K (PK)-resistant and self-perpetuating recombinant PrP conformers (rPrP-res) with PK-resistant cores of 17 or 14 kDa were generated. A bioassay revealed that rPrP-res(17kDa) was highly infectious, causing prion disease in wild-type mice with an average survival time of about 172 d. In contrast, rPrP-res(14kDa) completely failed to induce any disease. Our findings reveal that sPMCA is sufficient to initiate various self-perpetuating PK-resistant rPrP conformers, but not all of them possess in vivo infectivity. Moreover, generating an infectious prion in a prion-free environment establishes that an infectious prion can be formed de novo with bacterially expressed rPrP.


Assuntos
Príons/química , Animais , Encéfalo/patologia , Camundongos , Príons/patogenicidade , Dobramento de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química
13.
Food Funct ; 15(4): 1825-1839, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38315542

RESUMO

Ginsenosides are a class of natural products with hormone-like activity of triterpenoid saponins and have a variety of pharmacological activities such as anti-aging, immune regulation and cognitive improvement. With the great research interest in alternative medicine and natural products, they are gradually becoming research hotspots. Ginsenosides have a four-ring rigid steroid backbone similar to steroid hormones, and a series of experimental studies have shown that they can exhibit hormone-like activity by binding to nuclear receptors or affecting hormone levels, thereby affecting a wide range of inflammatory conditions, cancers, and menopause-related diseases. This review summarizes the mechanisms and potential health effects of ginsenosides exhibiting estrogen-like, glucocorticoid-like and androgen-like activities, providing an important reference for the exploration of safe phytohormone replacement therapy.


Assuntos
Produtos Biológicos , Ginsenosídeos , Panax , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Estrogênios , Receptores Citoplasmáticos e Nucleares , Esteroides
14.
Food Res Int ; 187: 114425, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38763673

RESUMO

In this study, composite gel was prepared from konjac glucomannan (KGM) and fibrin (FN). Composite gels with different concentration ratios were compared in terms of their mechanical properties, rheological properties, water retention, degradation rate, microstructure and biocompatibility. The results showed that the composite gels had better gel strength and other properties than non-composite gels. In particular, composite hydrogels with low Young's modulus formed when the KGM concentration was 0.8% and the FN concentration was 1.2%. The two components were cross linked through hydrogen-bond interaction, which formed a more stable gel structure with excellent water retention and in-vitro degradation rates, which were conducive to myogenic differentiation of ectomesenchymal stem cells (EMSCs). KGM-FN composite gel was applied to the preparation of cell-culture meat, which had similar texture properties and main nutrients to animal meat as well as higher content of dry base protein and dry base carbohydrate.


Assuntos
Fibrina , Hidrogéis , Mananas , Reologia , Mananas/química , Hidrogéis/química , Fibrina/química , Animais , Alicerces Teciduais/química , Células-Tronco Mesenquimais , Carne , Diferenciação Celular , Módulo de Elasticidade , Técnicas de Cultura de Células
15.
Int J Biol Macromol ; 256(Pt 2): 128538, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38043651

RESUMO

Hazelnut is one of the most popular nuts in the world, rich in nutrients and various active substances. In this study, soluble dietary fiber (SDF) was extracted from hazelnut kernels, and its physicochemical properties and absorbability were explored. Hazelnut-SDF exhibited ideal water-holding, oil-holding and swelling capacity, and glucose, cholesterol and cholate absorbing ability. Scanning electron microscopy and fourier transform infrared spectroscopy showed that hazelnut-SDF had typical polysaccharide structure of functional groups. The main monosaccharides were identified as arabinose, rhamnose, xylose, ribose, glucuronic acid, mannose and glucose by gas chromatography-mass spectrometry. In high-fat diet rats, hazelnut-SDF could improve serum lipid parameters, inhibit lipid accumulation in liver and adipocytes, and regulate the expression level of liver lipid synthesis-related genes. It also could adjust intestinal short chain fatty acids, promote the composition and structure of intestinal microbiota, and significantly balance the abundance of Alloprevotella, Fusicatenibacter, Lactobacillus, Roseburia, Ruminococcaceae_UCG-005, Ruminococcaceae_UCG-014 and Clostridiales. The results concluded that oral administration of hazelnut-SDF could alleviate hyperlipidemia and obesity, and might serve as a potential functional food ingredient.


Assuntos
Corylus , Microbioma Gastrointestinal , Ratos , Animais , Dieta Hiperlipídica/efeitos adversos , Fibras na Dieta/farmacologia , Fibras na Dieta/análise , Colesterol/farmacologia , Glucose/farmacologia
16.
Adv Mater ; 36(11): e2312125, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38052233

RESUMO

Twisted bilayer graphene (TBG) generates significant attention in the fundamental research of 2D materials due to its distinct twist-angle-dependent properties. Exploring the efficient production of TBG with a wide range of twist angles stands as one of the major frontiers in moiré materials. Here, the local space-confined chemical vapor deposition growth technique for high-quality single-crystal TBG with twist angles ranging from 0° to 30° on liquid copper substrates is reported. The clean surface, pristine interface, high crystallinity, and thermal stability of TBG are verified by using comprehensive characterization techniques including optical microscopy, electron microscopy, and secondary-ion mass spectrometry. The proportion of TBG in bilayer graphene reaches as high as 89%. In addition, the stacking structure and growth mechanism of TBG are investigated, revealing that the second graphene layer develops beneath the first one. A series of comparative experiments illustrates that the liquid copper surface, with its excellent fluidity, promotes the growth of TBG. Electrical measurements show the twist-angle-dependent electronic properties of as-grown TBG, achieving a room-temperature carrier mobility of 26640 cm2 V-1 s-1 . This work provides an approach for the in situ preparation of 2D twisted materials and facilitates the application of TBG in the fields of electronics.

17.
J Virol ; 86(3): 1874-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22090130

RESUMO

Whether a genetic informational nucleic acid is required for the infectivity of transmissible spongiform encephalopathies is central to the debate about the infectious agent. Here we report that an infectious prion formed with bacterially expressed recombinant prion protein plus synthetic polyriboadenylic acid and synthetic phospholipid 1-palmitoyl-2-oleoylphosphatidylglycerol is competent to infect cultured cells and cause prion disease in wild-type mice. Our results show that genetic informational RNA is not required for recombinant prion infectivity.


Assuntos
Príons/patogenicidade , RNA/genética , Animais , Camundongos , Fosfatidilgliceróis/metabolismo , Príons/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
18.
Food Chem ; 413: 135576, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36745946

RESUMO

As output of hazelnut increases worldwide, so does the amount of by-products, leading to huge waste and environmental stress. This paper focuses on the varieties of hazelnut that have been studied more in the past two decades, and summarizes the research status of hazelnut and its by-products from the aspects of nutritional value, phytochemicals, extraction methods, biological functions and applications. Hazelnut and its by-products are rich in a variety of bioactive constituents, mainly polyphenols, which have antioxidant, antibacterial and prebiotic effects. Moreover, hazelnut shells, husks, and leaves contain taxanes such as paclitaxel, which can inhibit the proliferation of cancer cells. They are potentially good natural sources of paclitaxel compared to the slower growing yew. Therefore, it is essential to further integrate the extraction techniques and health-promoting properties of these nutrients and bioactive substances to expand their application and enhance their value.


Assuntos
Corylus , Corylus/química , Antioxidantes/química , Polifenóis , Compostos Fitoquímicos , Paclitaxel
19.
Front Nutr ; 10: 1092071, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36819681

RESUMO

Hazel leaf, one of the by-products of hazelnut, which is widely used in traditional folk medicine around the world. In the present study, the profile of free, conjugated, and bound phenolic compounds from hazel leaf was detected and their antioxidant and anti-inflammatory activities were investigated. The potential health benefits of different phenolic compounds were also predicted. The results showed that the 35 phenolic substances of free, conjugated and bound forms were identified including phenolic acids, flavonoids and catechins. Most of the hazel leaf phenolics were presented in free form, followed by conjugated and bound form. All the fractions effectively inhibited the production of reactive oxygen species and malondialdehyde in TBHP-stimulated human umbilical vein endothelial cells by enhancing endogenous superoxide dismutase, and accordingly alleviated inflammatory cytokines (NO, IL-1ß, TNF-α, and IL-6) in LPS-stimulated RAW264.7 cells, showing obvious antioxidant and anti-inflammatory capacity. Moreover, combined with network pharmacology, the potential therapeutic effects and functional pathways of hazel leaf phenolics were predicted, which provided value basis for exploring their treatment on diseases and developing health products in the future.

20.
Nanoscale ; 15(5): 2067-2078, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36594492

RESUMO

Antiferromagnets (AFMs) are some of the most promising candidates for next-generation magnetic memory technology owing to their advantages over conventional ferromagnets (FMs), such as zero stray field and THz-range magnetic resonance frequency. Motivated by the recent synthesis of FeCl2 films with interlayer AFM and intralayer FM couplings, we investigated the magnetic properties of few-layer FeCl2 and the spin-dependent transmissions of graphite/bilayer FeCl2/graphite and Au/n-layer FeCl2/Au magnetic tunnel junctions (MTJs) using first-principles calculations combined with the nonequilibrium Green's function. The interlayer AFM coupling of FeCl2 is certified to be stable and independent of the stacking orders and relative displacement between layers. Furthermore, based on the Au electrode with better conductive performance than the graphite electrode and monolayer 1T-FeCl2 with complete spin polarization, high Curie temperature and large magnetic anisotropic energy, a high tunnel magnetoresistance (TMR) ratio of 2.7 × 103% is achieved in Au/bilayer FeCl2/Au MTJs at zero bias and it increases with different layers of FeCl2 (n = 2-10). These excellent spin transport properties of Au/n-layer FeCl2/Au MTJs based on two-dimensional (2D) AFM barriers with out-of-plane magnetization directions suggest their great potential for application in high-reliability, high-speed and high-density spintronic devices.

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