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1.
Small ; 20(25): e2307276, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38196162

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-37686129

RESUMO

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.


Assuntos
Allium , Antígenos CD13 , Simulação de Acoplamento Molecular , Cinética , Modelos Moleculares
3.
Photochem Photobiol Sci ; 21(12): 2217-2230, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36103110

RESUMO

Rosa davurica is widely used to treat various kinds of diseases because of its high antioxidant, antiviral and anti-inflammatory activities. This use of plant-based materials as medicine is called phytomedicine and has been widely practiced since time immemorial. However, the pharmacological mechanism of R. davurica in skin photoaging is not yet fully understood. Therefore, this study was carried out to evaluate the recovery effects of R. davurica leaf extracts (RDE) in UVB-irradiated human skin keratinocytes (HaCaTs) and investigate whether RDE is a potential therapeutic agent against skin photoaging. The expression of aging-related markers including mitogen-activated protein kinases/activator protein 1 (MAPK/AP-1), nuclear factor-κB (NF-κB), and nuclear factor E2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) was evaluated using Western blot analysis. The reactive oxygen species (ROS) was also used by FACS in HaCaTs. Findings indicated that RDE is efficient in scavenging free radicals and dose-dependently reducing ROS generation. Furthermore, RDE notably decreased UVB-induced matrix metalloproteinase-1 (MMP-1) expression through inhibition of MAPK/AP-1 and NF-κB signaling pathways as well as induced blocking of extracellular matrix (ECM) degradation in UVB-irradiated HaCaTs. In addition, RDE improved Nrf2/HO-1 signaling that increases oxidative defense capacity and enhances transforming growth factor-beta (TGF-ß) signaling activation to promote procollagen type I synthesis, relieving UVB-induced skin cell damage. In conclusion, the protective effects of RDE on skin cellular components suggest that it has a high biological potential for skin protection from UVB-induced skin photoaging and is a good candidate for drug and cosmetic application.


Assuntos
Extratos Vegetais , Rosa , Envelhecimento da Pele , Humanos , Heme Oxigenase-1 , Proteínas Quinases Ativadas por Mitógeno , Fator 2 Relacionado a NF-E2 , NF-kappa B , Rosa/química , Fator de Transcrição AP-1 , Envelhecimento da Pele/efeitos dos fármacos , Células HaCaT , Extratos Vegetais/farmacologia , Raios Ultravioleta
4.
Molecules ; 27(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35684431

RESUMO

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.


Assuntos
Maclura , Trombose , Fatores de Coagulação Sanguínea/metabolismo , Plaquetas/metabolismo , Fibrina , Fibrinolíticos/farmacologia , Humanos , Hidroxibenzoatos/metabolismo , Trombina/metabolismo , Trombose/metabolismo
5.
Molecules ; 26(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073317

RESUMO

Myrciaria dubia (HBK) McVaugh (camu-camu) belongs to the family Myrtaceae. Although camu-camu has received a great deal of attention for its potential pharmacological activities, there is little information on the anti-oxidative stress and anti-inflammatory effects of camu-camu fruit in skin diseases. In the present study, we investigated the preventative effect of 70% ethanol camu-camu fruit extract against high glucose-induced human keratinocytes. High glucose-induced overproduction of reactive oxygen species (ROS) was inhibited by camu-camu fruit treatment. In response to ROS reduction, camu-camu fruit modulated the mitogen-activated protein kinases (MAPK)/activator protein-1 (AP-1), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and nuclear factor of activated T cells (NFAT) signaling pathways related to inflammation by downregulating the expression of proinflammatory cytokines and chemokines. Furthermore, camu-camu fruit treatment activated the expression of nuclear factor E2-related factor 2 (Nrf2) and subsequently increased the NAD(P)H:quinone oxidoreductase1 (NQO1) expression to protect keratinocytes against high-glucose-induced oxidative stress. These results indicate that camu-camu fruit is a promising material for preventing oxidative stress and skin inflammation induced by high glucose level.


Assuntos
Queratinócitos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fatores de Transcrição NFATC/metabolismo , Estresse Oxidativo , Extratos Vegetais/farmacologia , Anti-Inflamatórios/farmacologia , Compostos de Bifenilo/química , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Avaliação Pré-Clínica de Medicamentos , Frutas/metabolismo , Glucose/metabolismo , Humanos , Inflamação/metabolismo , Queratinócitos/citologia , Sistema de Sinalização das MAP Quinases , Myrtaceae , NAD(P)H Desidrogenase (Quinona)/metabolismo , Picratos/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
6.
J Biochem Mol Toxicol ; 32(12): e22223, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30273962

RESUMO

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.


Assuntos
Fármacos Antiobesidade/farmacologia , Álcoois Benzílicos/farmacologia , Citrato (si)-Sintase/antagonistas & inibidores , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Lipase/antagonistas & inibidores , Obesidade/enzimologia , alfa-Glucosidases/efeitos dos fármacos , Animais , Humanos , Concentração Inibidora 50 , Cinética , Moraceae/química , Extratos Vegetais/farmacologia , Suínos
7.
J Biochem Mol Toxicol ; 32(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29077251

RESUMO

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.


Assuntos
Anticoagulantes/uso terapêutico , Ácidos Cumáricos/uso terapêutico , Modelos Animais de Doenças , Inibidores da Agregação Plaquetária/uso terapêutico , Tromboembolia/prevenção & controle , Células 3T3-L1 , Animais , Anticoagulantes/efeitos adversos , Anticoagulantes/farmacologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Retração do Coágulo/efeitos dos fármacos , Ácidos Cumáricos/efeitos adversos , Ácidos Cumáricos/farmacologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Células Hep G2 , Humanos , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Células NIH 3T3 , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/farmacologia , Serotonina/química , Serotonina/metabolismo , Antagonistas da Serotonina/efeitos adversos , Antagonistas da Serotonina/farmacologia , Antagonistas da Serotonina/uso terapêutico
8.
J Biochem Mol Toxicol ; 31(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27704645

RESUMO

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.


Assuntos
Ácido Clorogênico/administração & dosagem , Fibrinolíticos/administração & dosagem , Trombose/tratamento farmacológico , Tromboembolia Venosa/tratamento farmacológico , Células 3T3-L1 , Animais , Coagulação Sanguínea/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Epinefrina/toxicidade , Fator XIIIa/metabolismo , Fator Xa/metabolismo , Fibrina/metabolismo , Humanos , Camundongos , Agregação Plaquetária/efeitos dos fármacos , Trombose/sangue , Trombose/patologia , Tromboembolia Venosa/sangue , Tromboembolia Venosa/induzido quimicamente
9.
Prep Biochem Biotechnol ; 47(6): 539-546, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-27136080

RESUMO

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.


Assuntos
Fibrinolíticos/isolamento & purificação , Carpóforos/enzimologia , Metaloproteases/isolamento & purificação , Pleurotus/enzimologia , Animais , Coagulação Sanguínea/efeitos dos fármacos , Fibrinolíticos/metabolismo , Fibrinolíticos/uso terapêutico , Carpóforos/metabolismo , Humanos , Masculino , Metaloproteases/metabolismo , Metaloproteases/uso terapêutico , Camundongos Endogâmicos ICR , Pleurotus/metabolismo , Tromboembolia/sangue , Tromboembolia/tratamento farmacológico
10.
J Biochem Mol Toxicol ; 30(11): 548-558, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27271803

RESUMO

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.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Fibrinolíticos/farmacologia , Flavonoides/farmacologia , Quercetina/farmacologia , Trombina/antagonistas & inibidores , Tromboembolia/tratamento farmacológico , Doença Aguda , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Plaquetas/patologia , Colágeno/antagonistas & inibidores , Colágeno/farmacologia , Modelos Animais de Doenças , Epinefrina/antagonistas & inibidores , Epinefrina/farmacologia , Fator Xa/metabolismo , Fibrina/antagonistas & inibidores , Fibrina/metabolismo , Glucosídeos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ativação Plaquetária/efeitos dos fármacos , Cultura Primária de Células , Ratos Sprague-Dawley , Transdução de Sinais , Trombina/administração & dosagem , Tromboembolia/induzido quimicamente , Tromboembolia/metabolismo , Tromboembolia/patologia
11.
J Biochem Mol Toxicol ; 30(3): 111-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26418808

RESUMO

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.


Assuntos
Modelos Animais de Doenças , Inflamação/prevenção & controle , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Xantofilas/farmacologia , Animais , Catalase/metabolismo , Ciclo-Oxigenase 2/metabolismo , Edema/prevenção & controle , Camundongos , Camundongos Endogâmicos ICR , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação , Superóxido Dismutase/metabolismo
12.
J Biochem Mol Toxicol ; 29(5): 240-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25651404

RESUMO

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.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Fibrina/antagonistas & inibidores , Fibrinolíticos/farmacologia , Polissacarídeos/farmacologia , Trombose/tratamento farmacológico , Animais , Cianobactérias/química , Fibrinogênio/antagonistas & inibidores , Fibrinolíticos/química , Humanos , Camundongos , Polissacarídeos/química , Trombose/patologia
13.
J Biochem Mol Toxicol ; 29(12): 552-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26184785

RESUMO

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.


Assuntos
Antitrombinas/farmacologia , Luteolina/farmacologia , Trombose/prevenção & controle , Animais , Fatores de Coagulação Sanguínea/metabolismo , Artérias Carótidas/patologia , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley
14.
Neurochem Res ; 39(4): 707-18, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24549762

RESUMO

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.


Assuntos
Neurônios Dopaminérgicos/enzimologia , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Rotenona/toxicidade , Rutina/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Araliaceae , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Inibidores de Proteínas Quinases/isolamento & purificação , Rotenona/antagonistas & inibidores , Rutina/isolamento & purificação , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Int J Med Mushrooms ; 26(6): 53-68, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38801087

RESUMO

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.


Assuntos
Fibrinolíticos , Pycnoporus , Serina Proteases , Fibrinolíticos/farmacologia , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/química , Serina Proteases/isolamento & purificação , Serina Proteases/farmacologia , Serina Proteases/metabolismo , Serina Proteases/química , Animais , Pycnoporus/enzimologia , Peso Molecular , Carpóforos/química , Concentração de Íons de Hidrogênio , Temperatura , Humanos , Fibrina/metabolismo , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacologia
16.
Nat Commun ; 15(1): 2172, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467601

RESUMO

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.

17.
Adv Mater ; 36(30): e2400091, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38573312

RESUMO

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.

18.
ACS Nano ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264283

RESUMO

The relentless miniaturization inherent in complementary metal-oxide semiconductor technology has created challenges at the interface of two-dimensional (2D) materials and metal electrodes. These challenges, predominantly stemming from metal-induced gap states (MIGS) and Schottky barrier heights (SBHs), critically impede device performance. This work introduces an innovative implementation of damage-free Sb2Te3 topological van der Waals (T-vdW) contacts, representing an ultimate contact electrode for 2D materials. We successfully fabricate p-type and n-type transistors using monolayer and multilayer WSe2, achieving ultralow SBH (∼24 meV) and contact resistance (∼0.71 kΩ·µm). Simulations highlight the role of topological surface states in Sb2Te3, which effectively mitigate the MIGS effect, thereby significantly elevating device efficiency. Our experimental insights revealed the semiohmic behavior of Sb2Te3 T-vdW contacts, with an exceptional photoresponsivity of 716 A/W and rapid response times of approximately 60 µs. The findings presented herein herald topological contacts as a superior alternative to traditional metal contacts, potentially revolutionizing the performance of miniaturized electronic and optoelectronic devices.

19.
Foods ; 12(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37107470

RESUMO

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.

20.
Antioxidants (Basel) ; 12(8)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37627553

RESUMO

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.

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