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1.
Small ; 20(25): e2307276, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38196162

RESUMEN

Graphdiyne (GDY) has garnered significant attention as a cutting-edge 2D material owing to its distinctive electronic, optoelectronic, and mechanical properties, including high mobility, direct bandgap, and remarkable flexibility. One of the key challenges hindering the implementation of this material in flexible applications is its large area and uniform synthesis. The facile growth of centimeter-scale bilayer hydrogen substituted graphdiyne (Bi-HsGDY) on germanium (Ge) substrate is achieved using a low-temperature chemical vapor deposition (CVD) method. This material's field effect transistors (FET) showcase a high carrier mobility of 52.6 cm2 V-1 s-1 and an exceptionally low contact resistance of 10 Ω µm. By transferring the as-grown Bi-HsGDY onto a flexible substrate, a long-distance piezoresistive strain sensor is demonstrated, which exhibits a remarkable gauge factor of 43.34 with a fast response time of ≈275 ms. As a proof of concept, communication by means of Morse code is implemented using a Bi-HsGDY strain sensor. It is believed that these results are anticipated to open new horizons in realizing Bi-HsGDY for innovative flexible device applications.

2.
Int J Mol Sci ; 24(17)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37686129

RESUMEN

The primary objectives of this study were to assess the inhibitory effects of Allium ampeloprasum L. extract (AAE) and its derived organosulfur and polyphenolic compounds on the enzymatic activities of cGMP-specific PDE V (PDE5) and aminopeptidase N (APN). Additionally, the study aimed to investigate their potential as inhibitors against these two target enzymes through kinetic analyses and molecular docking studies. The in vitro enzyme assays demonstrated that both AAE and its derived compounds significantly decreased the activity of PDE5 and APN. Further analyses involving kinetics and molecular docking provided insights into the specific inhibitor types of AAE and its derived compounds along with the proposed molecular docking models illustrating the interactions between the ligands (the compounds) and the enzymes (PDE5 and APN). In particular, AAE-derived polyphenolic compounds showed relatively stable binding affinity (-7.2 to -8.3 kcal/mol) on PDE5 and APN. Our findings proved the potential as an inhibitor against PDE5 and APN of AAE and AAE-derived organosulfur and polyphenolic compounds as well as a functional material for erectile dysfunction improvement.


Asunto(s)
Allium , Antígenos CD13 , Simulación del Acoplamiento Molecular , Cinética , Modelos Moleculares
3.
Molecules ; 27(11)2022 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-35684431

RESUMEN

In blood coagulation, circulating platelets and coagulation factors are crucial for the primary process because thrombi are generated by fibrin clotting with fibrinogen, thrombin, FXIIIa, and platelet activation. Therefore, strategies to reduce the activity of key coagulation factors, or interfere with their functions and delay the activation of platelets can be used as important tools to suppress excessive blood clot formation and platelet hyperactivation. This study examined the antithrombotic activity and hematological toxicity of PA, IVA, and 4-HA isolated from M. tricuspidata (Carr.) Bur in several in vitro experiments and inhibitor assays. We found that PA, IVA, and 4-HA attenuated the formation of fibrin polymers/clots and degraded the blood clots. These compounds inhibited the activities of procoagulant proteases and fibrinoligase, and prolonged the coagulation time. There was a significant reduction in platelet function and ATP or serotonin levels in thrombin-activated platelets. An inhibitor study showed that PA exhibited a mixed inhibition type for thrombin, an uncompetitive inhibition type for FXa, and a non-competitive inhibition type for FXIIIa and IVA, while 4-HA exhibited an uncompetitive inhibition type for thrombin and non-competitive inhibition type for FXa and FXIIIa. These three compounds (up to 50 µg/mL) were not toxic to blood cells.


Asunto(s)
Maclura , Trombosis , Factores de Coagulación Sanguínea/metabolismo , Plaquetas/metabolismo , Fibrina , Fibrinolíticos/farmacología , Humanos , Hidroxibenzoatos/metabolismo , Trombina/metabolismo , Trombosis/metabolismo
4.
J Biochem Mol Toxicol ; 32(12): e22223, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30273962

RESUMEN

Recently, antiobesity studies using the method of inhibiting enzymatic activity of obesity-related enzymes as targets have received considerable attention. The aims of the current study were to investigate whether p-hydroxybenzyl alcohol (HBA), identified from Cudrania tricuspidata fruits with antiobesity effects, inhibits the activity of digestive and obesity-related enzymes and acts as an inhibitor against four target enzymes in kinetic studies. In vitro enzyme assays showed HBA at the highest concentration significantly reduced the enzymatic activity of four targets: pancreatic lipase (IC50 = 2.34-3.70 µM), α-glycosidase (IC50 = 9.08 µM), phosphodiesterase IV (IC50 = 4.99 µM), and citrate synthase (IC50 = 2.07 µM) enzymes. Based on the results of kinetic assays, the types of inhibition were investigated. Our findings indicate that HBA could have antiobesity efficacy, and it deserves further study.


Asunto(s)
Fármacos Antiobesidad/farmacología , Alcoholes Bencílicos/farmacología , Citrato (si)-Sintasa/antagonistas & inhibidores , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 4/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Lipasa/antagonistas & inhibidores , Obesidad/enzimología , alfa-Glucosidasas/efectos de los fármacos , Animales , Humanos , Concentración 50 Inhibidora , Cinética , Moraceae/química , Extractos Vegetales/farmacología , Porcinos
5.
J Biochem Mol Toxicol ; 32(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29077251

RESUMEN

We discovered recently in vitro and in vivo antithrombotic and cytotoxicity effects of ferulic acid. The cytotoxicity assays showed that ferulic acid (∼300 µg/mL) did not cause any significant toxicity on three cell lines, platelets, leukocytes, and erythrocytes. In vitro assays showed inhibitory effects of ferulic acid on thrombin (THR)- or collagen/epinephrine-stimulated platelet activation by inhibiting platelet aggregation, and decreasing clot retraction activity. The in vitro effect of ferulic acid on THR-stimulated platelet activation was proved by the decrease in the secretion of serotonin from the platelets. The anticoagulant effects of ferulic acid were confirmed by the prolongation of the intrinsic or/and extrinsic pathways and the delay of recalcification time in plasma coagulation. Ferulic acid had antithrombotic effect in acute thromboembolism model in vivo, and decreased the expression of αIIb ß3 /FIB and phosphorylation of AKT in THR-stimulated platelet activation in vivo, and their antithrombotic efficacies hold promise for therapeutic targeting in our ongoing studies.


Asunto(s)
Anticoagulantes/uso terapéutico , Ácidos Cumáricos/uso terapéutico , Modelos Animales de Enfermedad , Inhibidores de Agregación Plaquetaria/uso terapéutico , Tromboembolia/prevención & control , Células 3T3-L1 , Animales , Anticoagulantes/efectos adversos , Anticoagulantes/farmacología , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Supervivencia Celular/efectos de los fármacos , Retracción del Coagulo/efectos de los fármacos , Ácidos Cumáricos/efectos adversos , Ácidos Cumáricos/farmacología , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Hemostasis/efectos de los fármacos , Células Hep G2 , Humanos , Leucocitos/citología , Leucocitos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos ICR , Células 3T3 NIH , Agregación Plaquetaria/efectos de los fármacos , Inhibidores de Agregación Plaquetaria/efectos adversos , Inhibidores de Agregación Plaquetaria/farmacología , Serotonina/química , Serotonina/metabolismo , Antagonistas de la Serotonina/efectos adversos , Antagonistas de la Serotonina/farmacología , Antagonistas de la Serotonina/uso terapéutico
6.
J Biochem Mol Toxicol ; 31(3)2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27704645

RESUMEN

Thrombosis is a leading cause of morbidity and mortality throughout the world. Thrombolytic agents are important for both the prevention and treatment of thrombosis. Fibrin clot and turbidity assays revealed that it was able to inhibit the formation of fibrin clot. Chlorogenic acid degraded blood clot and inhibited the enzymatic activity of procoagulant proteases, thrombin, activated factor X (FXa), and activated factor XIII (FXIIIa). Chlorogenic acid was found to delay activated partial thromboplastin time, prothrombin time, and thrombin time. PFA-100 assays showed that it prolonged the closure time of citrated whole human blood. It demonstrated the antithrombotic effect in collagen and epinephrine-induced acute thromboembolism mice model. These antithrombotic profiles together with its anticoagulant and platelet disaggregation properties, and lack of toxicity to NIH-3T3 and 3T3-L1 cells, make it a potential agent for thrombotic treatment and prevention.


Asunto(s)
Ácido Clorogénico/administración & dosificación , Fibrinolíticos/administración & dosificación , Trombosis/tratamiento farmacológico , Tromboembolia Venosa/tratamiento farmacológico , Células 3T3-L1 , Animales , Coagulación Sanguínea/efectos de los fármacos , Colágeno/metabolismo , Modelos Animales de Enfermedad , Epinefrina/toxicidad , Factor XIIIa/metabolismo , Factor Xa/metabolismo , Fibrina/metabolismo , Humanos , Ratones , Agregación Plaquetaria/efectos de los fármacos , Trombosis/sangre , Trombosis/patología , Tromboembolia Venosa/sangre , Tromboembolia Venosa/inducido químicamente
7.
Prep Biochem Biotechnol ; 47(6): 539-546, 2017 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-27136080

RESUMEN

A fibrinolytic metalloprotease with in vitro fibrinolytic effects was purified from the edible mushroom Pleurotus ferulae using several chromatography steps including anion and ion exchange, gel filtration, and fast protein liquid chromatography columns. The molecular mass of the enzyme was estimated to be 20.0 kDa, as determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fibrin zymography. The protease was active at 50°C, and pH 4.0, 5.0, and 8.0. The fibrinolytic activity of the enzyme was inhibited by ethyleneglycol-bis-(2-aminoethyl)-N,N,N',N' tetraacetic acid and strongly inhibited by two metal ions, Cu and Mg. In vitro assays evaluating fibrinolytic activity on a fibrin plate, fibrin turbidity, and thrombolytic activity on fibrin clots using human fibrinogen and human thrombin revealed that the enzyme could hydrolyze fibrin polymers directly and inhibit the formation of fibrin clots. In activated partial thromboplastin time (APTT) and prothrombin time assays, the enzyme strongly prolonged the APTT, which detects an activity of intrinsic and common pathways. The enzyme showed strong in vivo protective effect against mortality/paralysis from epinephrine plus collagen-induced acute thromboembolism in in vivo model. Our findings suggest that the enzyme may have a potential for treatment and prevention of thrombosis-relative diseases.


Asunto(s)
Fibrinolíticos/aislamiento & purificación , Cuerpos Fructíferos de los Hongos/enzimología , Metaloproteasas/aislamiento & purificación , Pleurotus/enzimología , Animales , Coagulación Sanguínea/efectos de los fármacos , Fibrinolíticos/metabolismo , Fibrinolíticos/uso terapéutico , Cuerpos Fructíferos de los Hongos/metabolismo , Humanos , Masculino , Metaloproteasas/metabolismo , Metaloproteasas/uso terapéutico , Ratones Endogámicos ICR , Pleurotus/metabolismo , Tromboembolia/sangre , Tromboembolia/tratamiento farmacológico
8.
J Biochem Mol Toxicol ; 30(11): 548-558, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27271803

RESUMEN

The present study evaluates the in vitro, in vivo, and ex vivo antithrombotic and anticoagulant effect of two flavonoids: quercetin and quercetin-3-O-ß-d-glucoside (isoquercetin). The present results have shown that quercetin and isoquercetin inhibit the enzymatic activity of thrombin and FXa and suppress fibrin clot formation and blood clotting. The prolongation effect of quercetin and isoquercetin against epinephrine and collagen-induced platelet activation may have been caused by intervention in intracellular signaling pathways including coagulation cascade and aggregation response on platelets and blood. The in vivo and ex vivo anticoagulant efficacy of quercetin and isoquercetin was evaluated in thrombin-induced acute thromboembolism model and in ICR mice. Our findings showed that in vitro and in vivo inhibitory effects of quercetin were slightly higher than that of quercetin glucoside, whereas in vitro and ex vivo anticoagulant effects of quercetin were weaker than that of quercetin glucoside because of their structural characteristics.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Fibrinolíticos/farmacología , Flavonoides/farmacología , Quercetina/farmacología , Trombina/antagonistas & inhibidores , Tromboembolia/tratamiento farmacológico , Enfermedad Aguda , Animales , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Plaquetas/patología , Colágeno/antagonistas & inhibidores , Colágeno/farmacología , Modelos Animales de Enfermedad , Epinefrina/antagonistas & inhibidores , Epinefrina/farmacología , Factor Xa/metabolismo , Fibrina/antagonistas & inhibidores , Fibrina/metabolismo , Glucósidos , Masculino , Ratones , Ratones Endogámicos ICR , Activación Plaquetaria/efectos de los fármacos , Cultivo Primario de Células , Ratas Sprague-Dawley , Transducción de Señal , Trombina/administración & dosificación , Tromboembolia/inducido químicamente , Tromboembolia/metabolismo , Tromboembolia/patología
9.
J Biochem Mol Toxicol ; 30(3): 111-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26418808

RESUMEN

Undaria pinnatifida is a well-known traditional Korean food with a variety of biological activities. Carrageenan (carr) is commonly used to induce paw edema in animal models. This study was designed to elucidate the processes underlying the anti-inflammatory effect of fucoxanthin isolated from the sporophyll of U. pinnatifida in carr-induced paw edema in ICR mice. Fucoxanthin significantly decreased carr-induced increased nitric oxide levels in the plasma of mice with carr-induced paw edema. Fucoxanthin protected catalase (CAT) and superoxide dismutase (SOD) activity against disruption in mice with carr-induced paw edema. In addition, fucoxanthin repressed carr-induced activation of inducible nitric oxide synthase, cyclooxygenase-2, and nuclear factor kappa B, as well as carr-induced phosphorylation of mitogen-activated protein kinase, extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, and protein kinase B/Akt. These results suggest that fucoxanthin may have therapeutic potential as a treatment for patients with inflammatory diseases.


Asunto(s)
Modelos Animales de Enfermedad , Inflamación/prevención & control , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , FN-kappa B/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Xantófilas/farmacología , Animales , Catalasa/metabolismo , Ciclooxigenasa 2/metabolismo , Edema/prevención & control , Ratones , Ratones Endogámicos ICR , Óxido Nítrico/sangre , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fosforilación , Superóxido Dismutasa/metabolismo
10.
J Biochem Mol Toxicol ; 29(5): 240-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25651404

RESUMEN

We investigated in vitro and in vivo fibrinolytic and antithrombotic activity of spirulan and analyzed its partial biochemical properties. Spirulan, a sulfated polysaccharide from the blue-green alga Arthrospira platensis, exhibits antithrombotic potency. Spirulan showed a strong fibrin zymogram lysis band corresponding to its molecular mass. It specifically cleaved Aα and Bß, the major chains of fibrinogen. Spirulan directly decreased the activity of thrombin and factor X activated (FXa), procoagulant proteins. In vitro assays using human fibrin and mouse blood clots showed fibrinolytic and hemolytic activities of spirulan. Spirulan (2 mg/kg) showed antithrombotic effects in the ferric chloride (FeCl3 )-induced carotid arterial thrombus model and collagen and epinephrine-induced pulmonary thromboembolism mouse model. These results may be attributable to the prevention of thrombus formation and partial lysis of thrombus. Therefore, we suggest that spirulan may be a potential antithrombotic agent for thrombosis-related diseases.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Fibrina/antagonistas & inhibidores , Fibrinolíticos/farmacología , Polisacáridos/farmacología , Trombosis/tratamiento farmacológico , Animales , Cianobacterias/química , Fibrinógeno/antagonistas & inhibidores , Fibrinolíticos/química , Humanos , Ratones , Polisacáridos/química , Trombosis/patología
11.
J Biochem Mol Toxicol ; 29(12): 552-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26184785

RESUMEN

The objectives of present study were to investigate whether luteolin affects procoagulant proteinase activity and fibrin clot formation and influences thrombosis and coagulation in Sprague-Dawle rats. Luteolin significantly inhibited the enzymatic activity of thrombin and FXa activity by 29.1% and 16.2%. Luteolin also inhibited fibrin polymer formation in turbidity and microscopic analysis using fluorescent conjugate. Coagulation assay of luteolin was found to prolong activated partial thromboplastin time and prothrombin time. Moreover, luteolin protected the development of oxidative stress induced thrombosis in the FeCl3 -induced carotid arterial thrombus model. This study demonstrated that luteolin may be useful by reducing or preventing thrombotic challenge and can help us better understand the antithrombotic action of luteolin.


Asunto(s)
Antitrombinas/farmacología , Luteolina/farmacología , Trombosis/prevención & control , Animales , Factores de Coagulación Sanguínea/metabolismo , Arterias Carótidas/patología , Técnicas In Vitro , Masculino , Ratas , Ratas Sprague-Dawley
12.
Neurochem Res ; 39(4): 707-18, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24549762

RESUMEN

Dendropanax morbifera Leveille (Araliaceae) is well known in Korean traditional medicine for a variety of diseases. Rotenone is a commonly used neurotoxin to produce in vivo and in vitro Parkinson's disease models. This study was designed to elucidate the processes underlying neuroprotection of rutin, a bioflavonoid isolated from D. morbifera Leveille in cellular models of rotenone-induced toxicity. We found that rutin significantly decreased rotenone-induced generation of reactive oxygen species levels in SH-SY5Y cells. Rutin protected the increased level of intracellular Ca(2+) and depleted level of mitochondrial membrane potential (ΔΨm) induced by rotenone. Furthermore, it prevented the decreased ratio of Bax/Bcl-2 caused by rotenone treatment. Additionally, rutin protected SH-SY5Y cells from rotenone-induced caspase-9 and caspase-3 activation and apoptotic cell death. We also observed that rutin repressed rotenone-induced c-Jun N-terminal kinase and p38 mitogen-activated protein kinase phosphorylation. These results suggest that rutin may have therapeutic potential for the treatment of neurodegenerative diseases associated with oxidative stress.


Asunto(s)
Neuronas Dopaminérgicas/enzimología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Rotenona/toxicidad , Rutina/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Araliaceae , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Neuronas Dopaminérgicas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Fármacos Neuroprotectores/aislamiento & purificación , Fármacos Neuroprotectores/farmacología , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Inhibidores de Proteínas Quinasas/aislamiento & purificación , Rotenona/antagonistas & inhibidores , Rutina/aislamiento & purificación , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Int J Med Mushrooms ; 26(6): 53-68, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38801087

RESUMEN

The purification of a fibrinolytic enzyme from the fruiting bodies of wild-growing medicinal mushroom, Pycnoporus coccineus was achieved through a two-step procedure, resulting in its homogeneity. This purification process yielded a significant 4.13-fold increase in specific activity and an 8.0% recovery rate. The molecular weight of P. coccineus fibrinolytic enzyme (PCFE) was estimated to be 23 kDa using sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. PCFE demonstrated its optimal activity at a temperature of 40 °C and pH 8. Notably, the enzymatic activity was inhibited by the presence of zinc or copper metal ions, as well as serine protease inhibitors, such as phenylmethylsulfonyl fluoride and 4-amidinophenylmethanesulfonyl fluoride. PCFE exhibited remarkable specificity towards a synthetic chromogenic substrate for thrombin. The enzyme demonstrated the Michaelis-Menten constant (Km), maximal velocity (V ), and catalytic rate constant (Kcat) values of 3.01 mM, 0.33 mM min-1 µg-1, and 764.1 s-1, respectively. In vitro assays showed PCFE's ability to effectively degrade fibrin and blood clots. The enzyme induced alterations in the density and structural characteristics of fibrin clots. PCFE exhibited significant effects on various clotting parameters, including recalcification time, activated partial thromboplastin time, prothrombin time, serotonin secretion from thrombin-activated platelets, and thrombin-induced acute thromboembolism. These findings suggest that P. coccineus holds potential as an antithrombotic biomaterials and resources for cardiovascular research.


Asunto(s)
Fibrinolíticos , Pycnoporus , Serina Proteasas , Fibrinolíticos/farmacología , Fibrinolíticos/aislamiento & purificación , Fibrinolíticos/química , Serina Proteasas/aislamiento & purificación , Serina Proteasas/farmacología , Serina Proteasas/metabolismo , Serina Proteasas/química , Animales , Pycnoporus/enzimología , Peso Molecular , Cuerpos Fructíferos de los Hongos/química , Concentración de Iones de Hidrógeno , Temperatura , Humanos , Fibrina/metabolismo , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacología
14.
Adv Mater ; 36(30): e2400091, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38573312

RESUMEN

Crystallographic characteristics, including grain boundaries and crystallographic orientation of each grain, are crucial in defining the properties of two-dimensional materials (2DMs). To date, local microstructure analysis of 2DMs, which requires destructive and complex processes, is primarily used to identify unknown 2DM specimens, hindering the subsequent use of characterized samples. Here, a nondestructive large-area 2D crystallographic analytical method through sticky-note-like van der Waals (vdW) assembling-disassembling is presented. By the vdW assembling of veiled polycrystalline graphene (PCG) with a single-atom-thick single-crystalline graphene filter (SCG-filter), detailed crystallographic information of each grain in PCGs is visualized through a 2D Raman signal scan, which relies on the interlayer twist angle. The scanned PCGs are seamlessly separated from the SCG-filter using vdW disassembling, preserving their original condition. The remaining SCG-filter is then reused for additional crystallographic scans of other PCGs. It is believed that the methods can pave the way for advances in the crystallographic analysis of single-atom-thick materials, offering huge implications for the applications of 2DMs.

15.
Nat Commun ; 15(1): 2172, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467601

RESUMEN

Semi-infinite single-atom-thick graphene is an ideal reinforcing material that can simultaneously improve the mechanical, electrical, and thermal properties of matrix. Here, we present a float-stacking strategy to accurately align the monolayer graphene reinforcement in polymer matrix. We float graphene-poly(methylmethacrylate) (PMMA) membrane (GPM) at the water-air interface, and wind-up layer-by-layer by roller. During the stacking process, the inherent water meniscus continuously induces web tension of the GPM, suppressing wrinkle and folding generation. Moreover, rolling-up and hot-rolling mill process above the glass transition temperature of PMMA induces conformal contact between each layer. This allows for pre-tension of the composite, maximizing its reinforcing efficiency. The number and spacing of the embedded graphene fillers are precisely controlled. Notably, we accurately align 100 layers of monolayer graphene in a PMMA matrix with the same intervals to achieve a specific strength of about 118.5 MPa g-1 cm3, which is higher than that of lightweight Al alloy, and a thermal conductivity of about 4.00 W m-1 K-1, which is increased by about 2,000 %, compared to the PMMA film.

16.
Foods ; 12(8)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37107470

RESUMEN

The study investigated the effects of Petasites japonicus (Siebold & Zucc.) Maxim. extract (PJE) and fenofibrate on diet-induced obesity (DIO) in mice. PJE was found to contain various bio-active polyphenolic compounds, including kaempferol, p-hydroxybenzoic acid, ferulic acid, gallic acid, chlorogenic acid, 3,4-dicaffeoylquinic acid, caffeic acid, quercetin, rutin, protocatechuic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, p-coumaric acid, apigenin, and 1,3-dicaffeoylquinic acid. The results showed that PJE treatment up to 1000 µg/mL did not affect the viability of 3T3-L1 cell line, and it reduced the feed efficiency ratio in DIO mice. PJE administration also resulted in a significant reduction in body weight gain and fat accumulation in the liver compared to the DIO control group. Additionally, PJE administration improved the levels of lipid and related parameters, including total cholesterol, triacylglycerol, low-density lipoprotein, very low-density lipoprotein, glucose, insulin, insulin resistance, leptin, and atherogenic or cardiac indexes compared to the DIO control group. The study suggested that PJE may have a beneficial effect on insulin resistance, lipid profiles, atherogenesis, adipokines, and cardiac risk associated with diet-induced obesity.

17.
ACS Appl Mater Interfaces ; 15(5): 7274-7281, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36719071

RESUMEN

We successfully demonstrated the improvement and stabilization of the electrical properties of a graphene field effect transistor by fabricating a sandwiched amorphous boron nitride (a-BN)/graphene (Gr)/a-BN using a directly grown a-BN film. The a-BN film was grown via low-pressure chemical vapor deposition (LPCVD) at a low growth temperature of 250 °C and applied as a protection layer in the sandwiched structure. Both structural and chemical states of the as-grown a-BN were verified by various spectroscopic and microscopic analyses. We analyzed the Raman spectra of Gr/SiO2 and a-BN/Gr/a-BN structures to determine the stability of the device under exposure to ambient air. Following exposure, the intensity of the 2D/G-peak ratio of Gr/SiO2 decreased and the position of the G and 2D peaks red-shifted due to the degradation of graphene. In contrast, the peak position of encapsulated graphene is almost unchanged. We also confirmed that the mobility of a-BN/Gr/a-BN structure is 17,941 cm2/Vs. This synthetic strategy could provide a facile way to synthesize uniform a-BN film for encapsulating various van der Waals materials, which is beneficial for future applications in nanoelectronics.

18.
Antioxidants (Basel) ; 12(8)2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37627553

RESUMEN

The antioxidative proteolytic fraction, MA-1, was partially purified from Mycoleptodonoides aitchisonii. MA-1 was purified to homogeneity using a two-step procedure, which resulted in an 89-fold increase in specific activity and 42.5% recovery. SDS-PAGE revealed two proteins with a molecular weight of 48 kDa. The zymography results revealed proteolytic activity based on the MA-1 band. MA-1 was found to be stable in the presence of Na+, Ca2+, Fe3+, K+, and Mg2+. MA-1 was also stable in methanol, ethanol, and acetone, and its enzyme activity increased by 15% in SDS. MA-1 was inhibited by ethylenediaminetetra-acetic acid or ethylene glycol tetraacetic acid and exerted the highest specificity for the substrate, MeO-Suc-Arg-Pro-Tyr-pNA, for chymotrypsin. Accordingly, MA-1 belongs to the family of chymotrypsin-like metalloproteins. The optimum temperature was 40 °C and stability was stable in the range of 20 to 35 °C. The optimum pH and stability were pH 5.5 and pH 4-11. MA-1 exhibited stronger fibrinolytic activity than plasmin. MA-1 hydrolyzed the Aα, Bß, and γ chains of fibrinogen within 2 h. MA-1 exhibited an antithrombotic effect in animal models. MA-1 was devoid of hemorrhagic activity at a dose of 80,000 U/kg. Overall, our results show that M. aitchisonii produces an acid-tolerant and antioxidative chymotrypsin-like fibrinolytic enzyme, and M. aitchisonii containing MA-1 could be a beneficial functional material for the prevention of cardiovascular diseases and possible complications.

19.
Int J Med Mushrooms ; 23(4): 47-57, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33822507

RESUMEN

A fibrinolytic enzyme with thrombolytic, anticoagulant activities was purified from fruiting bodies of wild-growing mushroom Boletus pseudocalopus Hongo and homogenized with a two-step procedure with a 6.11-fold increase in specific activity and 3.2% recovery. The molecular weight of the enzyme was estimated to be 63.5 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The enzyme was active at 40°C and pH 7, and activity was inhibited by zinc metal ion and by serine protease and trypsin inhibitors phenylmethylsulfonyl fluoride and N-α-tosyl-l-lysinyl-chloromethylketone. The enzyme displayed high specificity for Pyro-Glu-Gly-Arg-pNA. In vitro assays showed that the enzyme was able to degrade fibrin and blood clots, inhibit thrombin and activated factor X, and alter the density or structural change of fibrin clots. It could also delay activated partial thromboplastin time and prothrombin time. These results suggest that the enzyme may have characteristics of a trypsin or serine-like enzyme with fibrinolytic and thrombolytic activities and may have potential as an antithrombotic agent for blood clotting disorders.


Asunto(s)
Basidiomycota/enzimología , Fibrinolíticos/aislamiento & purificación , Cuerpos Fructíferos de los Hongos/enzimología , Pruebas de Coagulación Sanguínea , Tiempo de Lisis del Coágulo de Fibrina , Fibrinólisis/efectos de los fármacos , Fibrinolíticos/farmacología , Concentración de Iones de Hidrógeno , Metales/química , Metales/farmacología , Microscopía Fluorescente , Peso Molecular , Nefelometría y Turbidimetría , Inhibidores de Proteasas/farmacología , República de Corea , Temperatura
20.
J Food Biochem ; : e13838, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34212412

RESUMEN

We found that the fermented Lentinula edodes (FLE) products exhibited various differences in terms of proximate composition, free sugar, and amino acid. In particular, there were higher levels of ergosterol, and ergothioneine in FLE-Pediococcus pentosaceus (PP) and -Lactobacillus acidophilus (LA) than in the L. edodes (LE) products. The survival rates of lactic acid bacteria (LAB) strains on artificial gastric juice, artificial bile, or heat (50-60°C) were observed to vary from 60%-66%, 60%-66%, to 42%-79%, respectively. The FLE products up to 300 µg/ml had no cytotoxicity on RAW264.7, AGS, and RBL-2H3 cells, but inhibited the activities of α-amylase, α-glucosidase, and pancreatic lipase, as well as the production of nitrite, IL-1ß, IL-4, TNF-α, and prostaglandin E2 (PGE2) from lipopolysaccharide (LPS)-induced inflammatory response. Our findings suggest that FLE products have metabolic enzyme inhibitory and anti-inflammatory effects. PRACTICAL APPLICATIONS: Fermentation plays a critical role in improving the functional and nutritional properties of food. In addition, lactobacteria are the main microorganisms involved in the fermentation of food known to have a variety of biological activities. Therefore, the utilization of lactobacteria for research and development of mushroom food materials can be used as a key strategy to improve the biological activity characteristics of mushroom food materials and to increase their active ingredient content. The present results show that FLE products had promising inhibitory efficacies against the activities of obesity-related metabolic enzymes and LPS-induced inflammatory response. These suggest that FLE products have the potential to be developed as functional probiotic dietary supplements or food products.

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