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1.
Life (Basel) ; 12(4)2022 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-35455095

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-26176000

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-24746735

RESUMEN

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.


Asunto(s)
Aster/química , Endopeptidasas/aislamiento & purificación , Fibrinolíticos/aislamiento & purificación , Proteínas de Plantas/aislamiento & purificación , Embolia Pulmonar/tratamiento farmacológico , Animales , Aster/enzimología , Pruebas de Coagulación Sanguínea , Cationes Bivalentes , Colágeno , Ácido Edético/química , Ácido Egtácico/química , Endopeptidasas/metabolismo , Endopeptidasas/farmacología , Fibrina/química , Fibrina/metabolismo , Fibrinógeno/química , Fibrinógeno/metabolismo , Fibrinólisis/efectos de los fármacos , Fibrinolíticos/metabolismo , Fibrinolíticos/farmacología , Calor , Cinética , Masculino , Ratones , Ratones Endogámicos ICR , Peso Molecular , Hojas de la Planta/química , Proteínas de Plantas/metabolismo , Proteínas de Plantas/farmacología , Plantas Medicinales , Embolia Pulmonar/sangre , Embolia Pulmonar/inducido químicamente , Zinc/química
4.
Neurochem Res ; 39(1): 84-96, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24214023

RESUMEN

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.


Asunto(s)
Fármacos Neuroprotectores/uso terapéutico , Enfermedad de Parkinson/fisiopatología , Rotenona/toxicidad , Triterpenos/uso terapéutico , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Triterpenos Pentacíclicos , Rotenona/antagonistas & inhibidores
5.
Appl Biochem Biotechnol ; 170(3): 609-22, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23564433

RESUMEN

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.


Asunto(s)
Proteínas Fúngicas/aislamiento & purificación , Metaloproteasas/aislamiento & purificación , Agaricales/enzimología , Secuencia de Aminoácidos , Cationes Bivalentes/farmacología , Fibrina/metabolismo , Fibrinógeno/metabolismo , Fibrinolisina/metabolismo , Fibrinólisis/efectos de los fármacos , Fibrinolíticos/aislamiento & purificación , Fibrinolíticos/metabolismo , Proteínas Fúngicas/antagonistas & inhibidores , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Metaloproteasas/antagonistas & inhibidores , Metaloproteasas/metabolismo , Datos de Secuencia Molecular , Peso Molecular , Especificidad por Sustrato , Temperatura , Activador de Tejido Plasminógeno/metabolismo
6.
Neurochem Res ; 35(8): 1269-80, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20467894

RESUMEN

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.


Asunto(s)
Antioxidantes/farmacología , Dopamina/metabolismo , Peróxido de Hidrógeno/farmacología , Fármacos Neuroprotectores/farmacología , Tripterygium , Apoptosis/efectos de los fármacos , Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Línea Celular , Activación Enzimática , Flavonoides/farmacología , Depuradores de Radicales Libres/farmacología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Fenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Tirosina 3-Monooxigenasa/biosíntesis
7.
J Agric Food Chem ; 58(3): 1543-50, 2010 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-20073473

RESUMEN

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.


Asunto(s)
Abietanos/farmacología , Neuroglía/citología , Nitroprusiato/toxicidad , Extractos Vegetales/farmacología , Rosmarinus/química , Salvia officinalis/química , Animales , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Fragmentación del ADN/efectos de los fármacos , Neuroglía/efectos de los fármacos , Neuroglía/metabolismo , Ratas
8.
Mycol Res ; 112(Pt 8): 990-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18550350

RESUMEN

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.


Asunto(s)
Fibrinolíticos/química , Fibrinolíticos/aislamiento & purificación , Metaloproteasas/química , Metaloproteasas/aislamiento & purificación , Polyporales/enzimología , Secuencia de Aminoácidos , Estabilidad de Enzimas , Fibrinolíticos/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Metaloproteasas/metabolismo , Datos de Secuencia Molecular , Peso Molecular , Micelio/química , Micelio/enzimología , Micelio/genética , Polyporales/química , Polyporales/genética , Alineación de Secuencia , Especificidad por Sustrato , Madera/microbiología
9.
J Microbiol Biotechnol ; 17(8): 1271-83, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18051595

RESUMEN

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.


Asunto(s)
Fibrina/metabolismo , Metaloproteasas/aislamiento & purificación , Metaloproteasas/metabolismo , Micelio/enzimología , Pleurotus/enzimología , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Cationes Bivalentes/farmacología , Cromatografía en Gel , Clonación Molecular , Coenzimas/farmacología , Ácido Edético/farmacología , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Metaloproteasas/química , Metaloproteasas/genética , Metales/farmacología , Datos de Secuencia Molecular , Peso Molecular , Oligopéptidos/metabolismo , Sistemas de Lectura Abierta , Pleurotus/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Análisis de Secuencia de Proteína , Homología de Secuencia de Aminoácido , Temperatura
10.
Biosci Biotechnol Biochem ; 71(9): 2214-22, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17827681

RESUMEN

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.


Asunto(s)
Agaricales/enzimología , Endopeptidasas/aislamiento & purificación , Endopeptidasas/metabolismo , Fibrinólisis , Secuencia de Aminoácidos , Cromatografía en Gel , Endopeptidasas/química , Activación Enzimática/efectos de los fármacos , Concentración de Iones de Hidrógeno , Metales/farmacología , Datos de Secuencia Molecular , Peso Molecular , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , Temperatura
11.
J Microbiol ; 44(6): 622-31, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17205040

RESUMEN

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.


Asunto(s)
Cordyceps/enzimología , Fibrina/metabolismo , Fibrinolíticos , Cuerpos Fructíferos de los Hongos/enzimología , Secuencia de Aminoácidos , Quimotripsina , Cordyceps/crecimiento & desarrollo , Medios de Cultivo , Fibrinolíticos/química , Fibrinolíticos/aislamiento & purificación , Fibrinolíticos/metabolismo , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Serina Endopeptidasas/química , Serina Endopeptidasas/aislamiento & purificación , Serina Endopeptidasas/metabolismo , Especificidad por Sustrato , Temperatura
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