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1.
Life (Basel) ; 12(4)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35455095

RESUMO

This study was a multicenter retrospective cohort study of term nulliparous women who underwent labor, and was conducted to develop an automated machine learning model for prediction of emergent cesarean section (CS) before onset of labor. Nine machine learning methods of logistic regression, random forest, Support Vector Machine (SVM), gradient boosting, extreme gradient boosting (XGBoost), light gradient boosting machine (LGBM), k-nearest neighbors (KNN), Voting, and Stacking were applied and compared for prediction of emergent CS during active labor. External validation was performed using a nationwide multicenter dataset for Korean fetal growth. A total of 6549 term nulliparous women was included in the analysis, and the emergent CS rate was 16.1%. The C-statistics values for KNN, Voting, XGBoost, Stacking, gradient boosting, random forest, LGBM, logistic regression, and SVM were 0.6, 0.69, 0.64, 0.59, 0.66, 0.68, 0.68, 0.7, and 0.69, respectively. The logistic regression model showed the best predictive performance with an accuracy of 0.78. The machine learning model identified nine significant variables of maternal age, height, weight at pre-pregnancy, pregnancy-associated hypertension, gestational age, and fetal sonographic findings. The C-statistic value for the logistic regression machine learning model in the external validation set (1391 term nulliparous women) was 0.69, with an overall accuracy of 0.68, a specificity of 0.83, and a sensitivity of 0.41. Machine learning algorithms with clinical and sonographic parameters at near term could be useful tools to predict individual risk of emergent CS during active labor in nulliparous women.

2.
Prev Nutr Food Sci ; 20(2): 126-32, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26176000

RESUMO

This study investigated the anti-amnesic effect of fermented Ganoderma lucidum water extracts (GW) on scopolamine-induced memory impairment in rats. GW were fermented by the lactic acid bacterium Bifidobacterium bifidum (FGWB), followed by Lactobacillus sakei LI033 (FGWBL). To induce amnesia, scopolamine (1 mg/kg) was intraperitoneally injected into rats 30 min before the behavioral tests. Step-through latencies of rats treated with primary fermented extracts (300 mg/kg, FGWB) and secondary fermented extracts (300 mg/kg, FGWBL) were significantly longer than those of rats treated with GW (300 mg/kg) in the retention trial of the multiple trial passive avoidance test. In the Morris water maze task, FGWBL significantly shortened escape latencies in training trials. Furthermore, swimming times within the target zone during the probe trial with FGWBL were significantly higher than the GW and FGWB treatments. In addition, acetylcholinesterase activities were lower in the brains of scopolamine-treated rats treated with FGWBL. These results suggest that FGWBL could be useful to enhance learning memory and cognitive function via cholinergic dysfunction.

3.
J Biosci Bioeng ; 118(4): 372-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24746735

RESUMO

A thrombolytic protease named kitamase possessing anticoagulant property was purified from edible and medicinal plant Aster yomena (Kitam.) Honda. Kitamase showed a molecular weight of 50 kDa by SDS-PAGE and displayed a strong fibrin zymogram lysis band corresponding to the similar molecular mass. The enzyme was active at high temperatures (50°C). The fibrinolytic activity of kitamase was strongly inhibited by EDTA, EGTA, TPCK and PMSF, inhibited by Zn(2+). The Km and Vmax values for substrate S-2251 were determined as 4.31 mM and 23.81 mM/mg respectively. It dissolved fibrin clot directly and specifically cleaved the α, Aα and γ-γ chains of fibrin and fibrinogen. In addition, kitamase delayed the coagulation time and increased activated partial thromboplastin time and prothrombin time. Kitamase exerted a significant protective effect against collagen and epinephrine induced pulmonary thromboembolism in mice. These results suggest that kitamase may have the property of metallo-protease like enzyme, novel fibrino(geno)lytic enzyme and a potential to be a therapeutic agent for thrombosis.


Assuntos
Aster/química , Endopeptidases/isolamento & purificação , Fibrinolíticos/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Embolia Pulmonar/tratamento farmacológico , Animais , Aster/enzimologia , Testes de Coagulação Sanguínea , Cátions Bivalentes , Colágeno , Ácido Edético/química , Ácido Egtázico/química , Endopeptidases/metabolismo , Endopeptidases/farmacologia , Fibrina/química , Fibrina/metabolismo , Fibrinogênio/química , Fibrinogênio/metabolismo , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/metabolismo , Fibrinolíticos/farmacologia , Temperatura Alta , Cinética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Peso Molecular , Folhas de Planta/química , Proteínas de Plantas/metabolismo , Proteínas de Plantas/farmacologia , Plantas Medicinais , Embolia Pulmonar/sangue , Embolia Pulmonar/induzido quimicamente , Zinco/química
4.
Neurochem Res ; 39(1): 84-96, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24214023

RESUMO

Celastrol, a potent natural triterpene and one of the most promising medicinal molecules, is known to possess a broad range of biological activity. Rotenone, a pesticide and complex I inhibitor, is commonly used to produce experimental models of Parkinson's disease both in vivo and in vitro. The present study was designed to examine the effects of celastrol on cell injury induced by rotenone in the human dopaminergic cells and to elucidate the possible mechanistic clues in its neuroprotective action. We demonstrate that celastrol protects SH-SY5Y cells from rotenone-induced cellular injury and apoptotic cell death. Celastrol also prevented the increased generation of reactive oxygen species and mitochondrial membrane potential (ΔΨm) loss induced by rotenone. Similarly, celastrol treatment inhibited cytochrome c release, Bax/Bcl-2 ratio changes, and caspase-9/3 activation. Celastrol specifically inhibited rotenone-evoked p38 mitogen-activated protein kinase activation in SH-SY5Y cells. These data suggest that celastrol may serve as a potent agent for prevention of neurotoxin-induced neurodegeneration through multiple mechanisms and thus has therapeutic potential for the treatment of neurodegenerative diseases.


Assuntos
Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/fisiopatologia , Rotenona/toxicidade , Triterpenos/uso terapêutico , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Triterpenos Pentacíclicos , Rotenona/antagonistas & inibidores
5.
Appl Biochem Biotechnol ; 170(3): 609-22, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23564433

RESUMO

Herinase, a new bi-functional fibrinolytic metalloprotease, was purified from a medicinal and edible mushroom Hericium erinaceum. The enzyme was monomeric with a molecular mass of 51 kDa. Analysis of fibrin zymography showed an active band with a similar molecular mass. The N-terminal sequence of herinase VPSSFRTTITDAQLRG was highly distinguished from known fibrinolytic enzymes. Moreover, the enzyme activity was strongly inhibited by EDTA and EGTA, indicating that herinase is a metalloprotease. Herinase exhibited high specificity for the substrate t-PA followed by plasmin. The K(m) and V(max) values for H-D-Ile-Pro-Arg-PNA were found to be 4.7 mg and 26.7 U/ml respectively. Similarly, fibrin plate assays revealed that it was able to degrade fibrin clot directly and also able to activate plasminogen. Herinase provoked a rapid degradation of fibrin and fibrinogen α chains and slower degradation of γ chains. It had no activity on the ß chains of fibrin and fibrinogen. This result suggests that herinase could possibly contain higher amount of α-fibrinogenase. The activity of herinase was stimulated by metal ions such as Ca(2+), Mg(2+), and Mn(2+), but inhibited by Cu(2+), Fe(2+), and Zn(2+). Herinase exhibited maximum activity at 30 °C and pH 7.0. These results demonstrate that herinase could be a novel fibrinolytic enzyme.


Assuntos
Proteínas Fúngicas/isolamento & purificação , Metaloproteases/isolamento & purificação , Agaricales/enzimologia , Sequência de Aminoácidos , Cátions Bivalentes/farmacologia , Fibrina/metabolismo , Fibrinogênio/metabolismo , Fibrinolisina/metabolismo , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/metabolismo , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Metaloproteases/antagonistas & inibidores , Metaloproteases/metabolismo , Dados de Sequência Molecular , Peso Molecular , Especificidade por Substrato , Temperatura , Ativador de Plasminogênio Tecidual/metabolismo
6.
Neurochem Res ; 35(8): 1269-80, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20467894

RESUMO

The present work was conducted to investigate the antioxidant activity and neuroprotective effects of Tripterygium regelii extract (TRE) on H(2)O(2)-induced apoptosis in human dopaminergic cells, SH-SY5Y. TRE possessed considerable amounts of phenolics (282.73 mg tannic acid equivalents/g of extract) and flavonoids (101.43 mg naringin equivalents/g of extract). IC(50) values for reducing power and DPPH radical scavenging activity were 52.51 and 47.83 microg, respectively. The H(2)O(2) scavenging capacity of TRE was found to be 57.68 microM x microg(-1) min(-1). By examining the effects of TRE on SH-SY5Y cells injured by H(2)O(2), we found that after incubation of cells with TRE prior to H(2)O(2) exposure, the H(2)O(2) induced cytotoxicity was significantly reversed and the apoptotic features such as change in cellular morphology, nuclear condensation and DNA fragmentation was inhibited. Moreover, TRE was very effective attenuating the disruption of mitochondrial membrane potential and apoptotic cell death induced by H(2)O(2). TRE extract effectively suppressed the up-regulation of Bax, Caspase-3 and -9, and down-regulation of Bcl-2. Moreover, TRE pretreatment evidently increased the tyrosine hydroxylase (TH) and brain-derived neurotrophic factor (BDNF) in SH-SY5Y cells. These findings demonstrate that TRE protects SH-SY5Y cells against H(2)O(2)-induced injury and antioxidant properties may account for its neuroprotective actions and suggest that TRE might potentially serve as an agent for prevention of neurodegenerative disease associated with oxidative stress.


Assuntos
Antioxidantes/farmacologia , Dopamina/metabolismo , Peróxido de Hidrogênio/farmacologia , Fármacos Neuroprotetores/farmacologia , Tripterygium , Apoptose/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Ativação Enzimática , Flavonoides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Tirosina 3-Mono-Oxigenase/biossíntese
7.
J Agric Food Chem ; 58(3): 1543-50, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20073473

RESUMO

Carnosol, a naturally occurring bioactive phenolic diterpene originating from rosemary and sage, has been shown to exert antioxidant and anti-inflammatory effects. This study examined possible protective effects of carnosol on sodium nitroprusside (SNP)-induced cytotoxicity in C6 glial cells. Carnosol (1-10 microM) dose-dependently attenuated SNP (100 microM)-induced cell death and NO production. SNP-induced apoptotic characteristics, including DNA fragmentation, caspase-3 activation, and c-jun N-terminal protein kinase (JNK) phosphorylation, were significantly suppressed by carnosol (10 microM). In addition, carnosol pretreatment restored the level of reduced glutathione (GSH), which was diminished by SNP treatment. Although both SNP (100 microM) and carnosol (10 microM) stimulated the HO-1 expression time-dependently, SNP caused a temporal increase in HO-1 in early time periods (3-6 h) before cell death occurred. In contrast, carnosol induced the sustained expression of HO-1 until a late time point (24 h). The addition of 1 microM zinc protoporphyrin IX (ZnPP), a specific HO inhibitor, with SNP or carnosol further reduced cell viability. Also, the addition of ZnPP inhibited the protective effect of carnosol against SNP-induced cytotoxicity in C6 cells. These results suggest that carnosol possesses abilities to inhibit SNP-mediated glial cell death through modulation of apoptotic events and induction of HO-1 expression.


Assuntos
Abietanos/farmacologia , Neuroglia/citologia , Nitroprussiato/toxicidade , Extratos Vegetais/farmacologia , Rosmarinus/química , Salvia officinalis/química , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Ratos
8.
Mycol Res ; 112(Pt 8): 990-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18550350

RESUMO

In this study we purified and characterized a fibrinolytic protease from the mycelia of Perenniporia fraxinea. The apparent molecular mass of the purified enzyme was estimated to be 42kDa by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), fibrin zymography and size exclusion using fast protein liquid chromatography (FPLC). The first 20 amino acid residues of the N-terminal sequence were ASYRVLPITKELLPPEFFVA, which shows a high degree of similarity with a fungalysin metallopeptidase from Coprinopsis cinerea. The optimal reaction pH value and temperature were pH 6.0 and 35-40 degrees C, respectively. Results for the fibrinolysis pattern showed that the protease rapidly hydrolyzed the fibrin alpha-chain followed by the beta-chain. The gamma-gamma chains were also hydrolyzed, but more slowly. The purified protease effectively hydrolyzed fibrinogen, preferentially digesting the Aalpha-chains of fibrinogen, followed by Bbeta- and gamma-chains. We found that protease activity was inhibited by Cu(2+), Fe(3+), and Zn(2+), but enhanced by the additions of Mn(2+), Mg(2+) and Ca(2+) metal ions. Furthermore, the protease activity was inhibited by EDTA, and it was found to exhibit a higher specificity for the chromogenic substrate S-2586 for chymotrypsin, indicating that the enzyme is a chymotrypsin-like metalloprotease. The mycelia of P. fraxinea may thus represent a source of new therapeutic agents to treat thrombosis.


Assuntos
Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Metaloproteases/química , Metaloproteases/isolamento & purificação , Polyporales/enzimologia , Sequência de Aminoácidos , Estabilidade Enzimática , Fibrinolíticos/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Metaloproteases/metabolismo , Dados de Sequência Molecular , Peso Molecular , Micélio/química , Micélio/enzimologia , Micélio/genética , Polyporales/química , Polyporales/genética , Alinhamento de Sequência , Especificidade por Substrato , Madeira/microbiologia
9.
J Microbiol Biotechnol ; 17(8): 1271-83, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18051595

RESUMO

A fibrinolytic protease (PoFE) was purified from the cultured mycelia of the edible oyster mushroom Pleurotus ostreatus, using a combination of various chromatographies. The purification protocol resulted in an 876-fold purification of the enzyme, with a final yield of 6.5%. The apparent molecular mass of the purified enzyme was estimated to be 32 kDa by SDS-PAGE, fibrin-zymography, and size exclusion using FPLC. The optimal reaction pH value and temperature were pH 6.5 and 35 degrees C, respectively. PoFE effectively hydrolyzed fibrinogen, preferentially digesting the A alpha-chain and the B beta-chain over the gamma-chain. Enzyme activity was enhanced by the addition of Ca2+, Zn2+, and Mg2+ ions. Furthermore, PoFE activity was potently inhibited by EDTA, and it was found to exhibit a higher specificity for the chromogenic substrate S-2586 for chymotrypsin, indicating that the enzyme is a chymotrypsin-like metalloprotease. The first 19 amino acid residues of the N-terminal sequence were ALRKGGAAALNIYSVGFTS, which is extremely similar to the metalloprotease purified from the fruiting body of P. ostreatus. In addition, we cloned the PoFE protein, encoding gene, and its nucleotide sequence was determined. The cDNA of cloned PoFE is 867 nucleotides long and consists of an open reading frame encoding 288 amino acid residues. Its cDNA showed a high degree of homology with PoMEP from P. ostreatus fruiting body. The mycelia of P. ostreatus may thus represent a potential source of new therapeutic agents to treat thrombosis.


Assuntos
Fibrina/metabolismo , Metaloproteases/isolamento & purificação , Metaloproteases/metabolismo , Micélio/enzimologia , Pleurotus/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Sequência de Bases , Cátions Bivalentes/farmacologia , Cromatografia em Gel , Clonagem Molecular , Coenzimas/farmacologia , Ácido Edético/farmacologia , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Metaloproteases/química , Metaloproteases/genética , Metais/farmacologia , Dados de Sequência Molecular , Peso Molecular , Oligopeptídeos/metabolismo , Fases de Leitura Aberta , Pleurotus/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Temperatura
10.
Biosci Biotechnol Biochem ; 71(9): 2214-22, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17827681

RESUMO

In this study we purified a fibrinolytic enzyme from the culture supernatant of Flammulina velutipes mycelia by ion exchange and gel filtration chromatographies, it was designated as F. velutipes protease (FVP-I). This purification protocol resulted in 18.52-fold purification of the enzyme at a final yield of 0.69%. The molecular mass of the purified enzyme was estimated to be 37 kDa by SDS-PAGE, fibrin-zymography and size exclusion by FPLC. This protease effectively hydrolyzed fibrin, preferentially digesting alpha-chain over beta-and gamma-gamma chain. Optimal protease activity was found to occur at a pH of 6.0 and a temperature of 20 to 30 degrees C. The protease activity was inhibited by Cu2+, Fe2+ and Fe3+ ions, but was found to be enhanced by Mn2+ and Mg2+ ions. Furthermore, FVP-I activity was potently inhibited by EDTA and EGTA, and it was found to exhibit a higher specificity for chromogenic substrate S-2586 for chymotrypsin, indicating that the enzyme is a chymotrypsin-like metalloprotease. The first 20 amino acid residues of the N-terminal sequence of FVP-I were LTYRVIPITKQAVTEGTELL. They had a high degree of homology with hypothetical protein CC1G_11771, GeneBank Accession no. EAU86463.


Assuntos
Agaricales/enzimologia , Endopeptidases/isolamento & purificação , Endopeptidases/metabolismo , Fibrinólise , Sequência de Aminoácidos , Cromatografia em Gel , Endopeptidases/química , Ativação Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Metais/farmacologia , Dados de Sequência Molecular , Peso Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Temperatura
11.
J Microbiol ; 44(6): 622-31, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17205040

RESUMO

In this study we purified a fibrinolytic enzyme from Cordyceps militaris using a combination of ion-exchange chromatography on a DEAE Sephadex A-50 column, gel filtration chromatography on a Sephadex G-75 column, and FPLC on a HiLoad 16/60 Superdex 75 column. This purification protocol resulted in a 191.8-fold purification of the enzyme and a final yield of 12.9 %. The molecular mass of the purified enzyme was estimated to be 52 kDa by SDS-PAGE, fibrin-zymography, and gel filtration chromatography. The first 19 amino acid residues of the N-terminal sequence were ALTTQSNV THGLATISLRQ, which is similar to the subtilisin-like serine protease PR1J from Metarhizium anisopliae var. anisopliase. This enzyme is a neutral protease with an optimal reaction pH and temperature of 7.4 and 37 degrees , respectively. Results for the fibrinolysis pattern showed that the enzyme rapidly hydrolyzed the fibrin alpha-chain followed by the gamma-gamma chains. It also hydrolyzed the beta-chain, but more slowly. The Aalpha, Bbeta, and gamma chains of fibrinogen were also cleaved very rapidly. We found that enzyme activity was inhibited by Cu2+ and Co2+, but enhanced by the additions of Ca2+ and Mg2+ ions. Furthermore, fibrinolytic enzyme activity was potently inhibited by PMSF and APMSF. This enzyme exhibited a high specificity for the chymotrypsin substrate S-2586 indicating it 's a chymotrypsin-like serine protease. The data we present suggest that the fibrinolytic enzyme derived from the edible and medicinal mushroom Cordyceps militaris has fibrin binding activity, which allows for the local activation of the fibrin degradation pathway.


Assuntos
Cordyceps/enzimologia , Fibrina/metabolismo , Fibrinolíticos , Carpóforos/enzimologia , Sequência de Aminoácidos , Quimotripsina , Cordyceps/crescimento & desenvolvimento , Meios de Cultura , Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/metabolismo , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Serina Endopeptidases/química , Serina Endopeptidases/isolamento & purificação , Serina Endopeptidases/metabolismo , Especificidade por Substrato , Temperatura
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