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1.
J Appl Microbiol ; 120(5): 1390-402, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26895351

RESUMEN

AIMS: Exopolysaccharide fraction from Pediococcus pentosaceus KFT18 (PE-EPS), a lactic acid bacteria isolated from Kimchi (a Korean fermented vegetable product), was preliminary characterized and its immunostimulating effects were analysed. METHODS AND RESULTS: In this study, we used interferon-γ (IFN-γ)-primed RAW 264·7 macrophages and CD3/CD28-stimulated splenocytes to determine the immunotimulatory activities of PE-EPS. Upon exposure to PE-EPS, IFN-γ-primed RAW 264·7 macrophages showed significant increases in the expressions of inducible nitric oxide synthase (iNOS), tumour necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1ß. Molecular data using reporter gene assay and electrophoretic mobility shift assay (EMSA) revealed that PE-EPS upregulated transcriptional activity, DNA binding and the nuclear translocation of nuclear factor-κB (NF-κB). Furthermore, PE-EPS enhanced anti-CD3/CD28-specific proliferation and the productions of IL-2 and IFN-γ in primary splenocytes. In cyclophosphamide-induced immunosuppressed mice, pretreatment with PE-EPS (5, 15 or 45 mg kg(-1) day(-1), p.o.) increased thymus and spleen indices, and improved lymphocyte and neutrophil counts. CONCLUSION: PE-EPS stimulated the IFN-γ-primed macrophages and primary splenocytes to induce immune responses and improved the cyclophosphamide-induced immunosuppression in mice. SIGNIFICANCE AND IMPACT OF THE STUDY: The results in this study improved our understanding of immunostimulating activity of PE-EPS and supported its potential treatment option as a natural immunostimulant.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Macrófagos/efectos de los fármacos , Pediococcus pentosaceus/química , Animales , Recuento de Células Sanguíneas , Línea Celular , Ensayo de Cambio de Movilidad Electroforética , Regulación de la Expresión Génica , Huésped Inmunocomprometido , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos ICR , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Bazo/citología , Bazo/inmunología , Bazo/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
2.
Clin Exp Dermatol ; 39(1): 25-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24341477

RESUMEN

BACKGROUND: Androgenetic alopecia (AGA) is the most common type of hair loss, and is characterized by the transformation of terminal scalp hair into vellus hair. The epidemiology of AGA is not fully understood. A strong genetic basis has long been identified, although little is known of its nongenetic causes. AIM: To evaluate the association of AGA with a number of environmental factors, including smoking, drinking and sleeping habit. METHODS: In total, 3114 Korean individuals with AGA who attended any one of 17 dermatology clinics in 6 cities in South Korea between March 2011 and February 2012 were enrolled in the study. Epidemiologic a data were collected using a standard questionnaire. RESULTS: No association was seen between eating or sleeping habits and severity of hair loss. However, drinking and smoking were associated with the severity of AGA in male patients. We also found that patients of both genders with a family history had more advanced types of hair loss, and the age of onset of AGA in male patients with a family history was earlier than that in male patients without a family history. CONCLUSIONS: Although the evidence for an environmental influence on AGA remains very weak, we did find an association between hair loss severity and certain environmental factors, such as smoking and drinking. Family history with more severe hair loss and an earlier age of onset.


Asunto(s)
Alopecia/epidemiología , Adulto , Distribución por Edad , Edad de Inicio , Consumo de Bebidas Alcohólicas/efectos adversos , Alopecia/etiología , Alopecia/fisiopatología , Femenino , Humanos , Estilo de Vida , Masculino , Prevalencia , República de Corea/epidemiología , Factores de Riesgo , Distribución por Sexo , Sueño/fisiología , Fumar/efectos adversos
3.
J Viral Hepat ; 19(5): 353-63, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22497815

RESUMEN

We identified heat shock protein 72 (Hsp72) as a host factor that was differentially expressed in cells expressing nonstructural 5A (NS5A) protein. To investigate how NS5A modulates Hsp72 in hepatitis C virus (HCV) life cycle, we examined the role of Hsp72 in HCV replication and virus production. NS5A specifically interacted with Hsp72. Both Hsp72 and nuclear factor of activated T cells 5 (NFAT5) levels were increased in cells expressing NS5A protein. Treatments of N-acetylcysteine and glutathione markedly reduced protein levels of both NFAT5 and Hsp72. Knockdown of NFAT5 resulted in decrease in Hsp72 level in cells expressing NS5A. Importantly, silencing of Hsp72 expression resulted in decrease in both RNA replication and virus production in HCV-infected cells. These data indicate that NS5A modulates Hsp72 via NFAT5 and reactive oxygen species activation for HCV propagation.


Asunto(s)
Proteínas del Choque Térmico HSP72/metabolismo , Hepacivirus/patogenicidad , Interacciones Huésped-Patógeno , Factores de Transcripción/metabolismo , Proteínas no Estructurales Virales/metabolismo , Replicación Viral , Línea Celular , Hepatocitos/virología , Humanos
4.
J Nanosci Nanotechnol ; 12(7): 5902-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22966678

RESUMEN

Nanocrystalline surface layer up to 84 microm in thick is produced on a specimen made of Al6061-T6 alloy by means of surface treatment called ultrasonic nanocrystalline surface modification (UNSM) technique. The refined grain size is produced in the top-layer and it is increased with increasing depth from the top surface. Vickers microhardness measurement for each nanocrystalline surface layer is performed and measurement results showed that the microhardness is increased from 116 HV up to 150 HV, respectively. In this study, fatigue behavior of Al6061-T6 alloy was studied up to 10(7)-10(9) cycles by using a newly developed ultrasonic fatigue testing (UFT) rig. The fatigue results of the UNSM-treated Al6061-T6 alloy specimens were compared with those of the untreated specimens. The microstructure of the untreated and UNSM-treated specimens was characterized by means of scanning electron microscopey (SEM) and transmission electron microscopey (TEM).

5.
J Periodontal Res ; 46(6): 712-21, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21745208

RESUMEN

BACKGROUND AND OBJECTIVE: Activation of sirtuin 1 (SIRT1) promotes the differentiation of keratinocytes and mesenchymal stem cells, but inhibits the differentiation of muscle and fat cells. However, the involvement of SIRT1 in the differentiation of human periodontal ligament cells into osteoblast-like cells remains unclear. To identify the role of SIRT1 in human periodontal ligament cells, we measured SIRT1 mRNA and SIRT1 protein levels during the osteoblastic differentiation of human periodontal ligament cells. Additionally, we investigated the effects of overexpressing and underexpressing SIRT1 on the differentiation of human periodontal ligament cells, and the signaling mechanisms involved. MATERIAL AND METHODS: Expression of SIRT1 and osteoblastic differentiation markers was assessed by RT-PCR, real-time PCR, Alizarin red staining and western blotting. RESULTS: Marked upregulation of SIRT1 mRNA and SIRT1 protein was observed in cells grown for 3 d in osteogenic induction medium (OM). Activation of SIRT1 using resveratrol and isonicotinamide stimulated osteoblastic differentiation in a dose-dependent manner, as assessed by the expression of mRNAs encoding alkaline phosphatase, osteopontin, osteocalcin, osterix and Runx2, and induced calcium deposition. In contrast, inhibition of SIRT1 using sirtinol, nicotinamide and gene silencing by RNA interference suppressed mineralization and the expression of osteoblast marker mRNAs. Further mechanistic studies revealed that resveratrol treatment increased the phosphorylation of Akt, adenosine monophosphate kinase (AMPK), Smad 1/5/8 and c-Jun N-terminal kinase, but reduced OM-induced activation of nuclear factor-κB. Conversely, application of sirtinol suppressed the phosphorylation of Akt, AMPK, Smad 1/5/8, p38, ERK and c-Jun N-terminal kinase, and enhanced nuclear factor-κB activity, in OM-stimulated cells. CONCLUSION: These data suggest that SIRT1 is a potent regulator of differentiation of human periodontal ligament cells and may have clinical implications for periodontal bone regeneration.


Asunto(s)
Osteoblastos/citología , Osteogénesis/genética , Ligamento Periodontal/citología , Sirtuina 1/biosíntesis , Sirtuina 1/fisiología , Diferenciación Celular/genética , Línea Celular Transformada , Regulación de la Expresión Génica , Humanos , Regeneración/genética , Sirtuina 1/genética
6.
Clin Otolaryngol ; 35(1): 25-30, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20447159

RESUMEN

OBJECTIVES: To determine the role of psychological distress in laryngopharyngeal reflux patients and evaluate the correlation between symptoms, laryngeal signs, pH monitoring results and psychological profile. DESIGN: Prospective study. SETTING: Hanyang University Hospital, a university teaching hospital and tertiary referral center. PARTICIPANTS: One hundred and six patients who were diagnosed with laryngopharyngeal reflux by 24-h ambulatory double probe pH monitoring and 119 healthy controls visiting our health promotion center from January 2006 to June 2007. MAIN OUTCOME MEASURES: The psychological profile of laryngopharyngeal reflux patients measured by the Symptom Checklist-90-Revised questionnaire were evaluated and compared with those of healthy controls. The correlation between reflux symptom index, reflux finding score, parameters of pH monitoring and the Symptom Checklist-90-Revised profiles were also evaluated. RESULTS: On the Symptom Checklist-90-Revised questionnaire, the total mean T-scores of the nine symptom dimensions and three global indices of the laryngopharyngeal reflux patients were all below 50. The Global Severity Index, which indicates overall psychological distress, was normal in all of the patients. On comparison with the control group, no statistically significant difference was noted in the psychological profile except on the Somatisation scale where laryngopharyngeal reflux patients showed significantly higher scores. Reflux symptom index showed significant positive correlation with the number of reflux episodes, percentage of time which pH fell below 4 in total positions, and DeMeester score of the upper probe. The nine symptom dimensions and three global indices of Symptom Checklist-90-Revised questionnaire did not show any correlation with reflux symptom index, reflux finding score and the parameters of the 24-h ambulatory double probe pH monitoring. CONCLUSIONS: Laryngopharyngeal reflux patients did not demonstrate any significant level of psychological distress and their symptom severity showed significant positive correlation with reflux severity.


Asunto(s)
Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/etiología , Reflujo Gastroesofágico/psicología , Encuestas y Cuestionarios , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Índice de Severidad de la Enfermedad
7.
J Cell Biol ; 130(5): 1127-36, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7657697

RESUMEN

Involvement of transglutaminase in myofibrillogenesis of chick embryonic myoblasts has been investigated in vitro. Both the activity and protein level of transglutaminase initially decreased to a minimal level at the time of burst of myoblast fusion but gradually increased thereafter. The localization of transglutaminase underwent a dramatic change from the whole cytoplasm in a diffuse pattern to the cross-striated sarcomeric A band, being strictly colocalized with the myosin thick filaments. For a brief period prior to the appearance of cross-striation, transglutaminase was localized in nonstriated filamental structures that coincided with the stress fiber-like structures. When 12-o-tetradecanoyl phorbol acetate was added to muscle cell cultures to induce the sequential disassembly of thin and thick filaments, transglutaminase was strictly colocalized with the myosin thick filaments even in the myosacs, of which most of the thin filaments were disrupted. Moreover, monodansylcadaverine, a competitive inhibitor of transglutaminase, reversibly inhibited the myofibril maturation. In addition, myosin heavy chain behaved as one of the potential intracellular substrates for transglutaminase. The cross-linked myosin complex constituted approximately 5% of the total Triton X-100-insoluble pool of myosin molecules in developing muscle cells, and its level was reduced to below 1% upon treatment with monodansylcadaverine. These results suggest that transglutaminase plays a crucial role in myofibrillogenesis of developing chick skeletal muscle.


Asunto(s)
Embrión de Pollo/citología , Miofibrillas/enzimología , Transglutaminasas/metabolismo , Animales , Diferenciación Celular/fisiología , Células Cultivadas/citología , Células Cultivadas/enzimología , Embrión de Pollo/enzimología , Pollos , Reactivos de Enlaces Cruzados/metabolismo , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/enzimología , Miosinas/metabolismo , Especificidad por Sustrato , Transglutaminasas/análisis , Transglutaminasas/antagonistas & inhibidores
8.
J Appl Microbiol ; 107(2): 514-23, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19486415

RESUMEN

AIMS: Elucidation of the regulation of ChiB production in Aspergillus nidulans. METHODS AND RESULTS: Mutational inactivation of the A. nidulans chiB gene resulted in a nonautolytic phenotype. To better understand the mechanisms controlling both developmental progression and fungal autolysis, we examined a range of autolysis-associated parameters in A. nidulans developmental and/or autolytic mutants. Investigation of disorganization of mycelial pellets, loss of biomass, extra-/intracellular chitinase activities, ChiB production and chiB mRNA levels in various cultures revealed that, in submerged cultures, initialization of autolysis and stationary phase-induced ChiB production are intimately coupled, and that both processes are controlled by the FluG-BrlA asexual sporulation regulatory pathway. ChiB production does not affect the progression of apoptotic cell death in the aging A. nidulans cultures. CONCLUSIONS: The endochitinase ChiB plays an important role in autolysis of A. nidulans, and its production is initiated by FluG-BrlA signalling. Despite the fact that apoptosis is an inseparable part of fungal autolysis, its regulation is independent to FluG-initiated sporulation signalling. SIGNIFICANCE AND IMPACT OF THE STUDY: Deletion of chiB and fluG homologues in industrial filamentous fungal strains may stabilize the hyphal structures in the autolytic phase of growth and limit the release of autolytic hydrolases into the culture medium.


Asunto(s)
Aspergillus nidulans/enzimología , Aspergillus nidulans/genética , Autólisis , Quitinasas/metabolismo , Proteínas Fúngicas/metabolismo , Anticuerpos Antifúngicos/inmunología , Aspergillus nidulans/crecimiento & desarrollo , Aspergillus nidulans/inmunología , Autólisis/genética , Autólisis/metabolismo , Biomasa , Quitina/metabolismo , Quitinasas/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiología , Regulación Fúngica de la Expresión Génica , Fenotipo , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Esporas Fúngicas/genética , Esporas Fúngicas/metabolismo
9.
Neuron ; 21(3): 617-21, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9768847

RESUMEN

Voltage-activated K+ channels are integral membrane proteins containing a potassium-selective transmembrane pore gated by changes in the membrane potential. This activation gating (opening) occurs in milliseconds and involves a gate at the cytoplasmic side of the pore. We found that substituting cysteine at a particular position in the last transmembrane region (S6) of the homotetrameric Shaker K+ channel creates metal binding sites at which Cd2+ ions can bind with high affinity. The bound Cd2+ ions form a bridge between the introduced cysteine in one channel subunit and a native histidine in another subunit, and the bridge traps the gate in the open state. These results suggest that gating involves a rearrangement of the intersubunit contacts at the intracellular end of S6. The recently solved structure of a bacterial K+ channel shows that the S6 homologs cross in a bundle, leaving an aperture at the bundle crossing. In the context of this structure, the metal ions form a bridge between a cysteine above the bundle crossing and a histidine below the bundle crossing in a neighboring subunit. Our results suggest that gating occurs at the bundle crossing, possibly through a change in the conformation of the bundle itself.


Asunto(s)
Cadmio/metabolismo , Activación del Canal Iónico/fisiología , Canales de Potasio/fisiología , Sustitución de Aminoácidos , Sitios de Unión , Cadmio/farmacología , Línea Celular , Humanos , Cinética , Sustancias Macromoleculares , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Canales de Potasio/química , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Canales de Potasio de la Superfamilia Shaker , Transfección
10.
Nat Biotechnol ; 18(6): 645-8, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10835603

RESUMEN

We have developed a recombinant live oral vaccine using the ice-nucleation protein (Inp) from Pseudomonas syringae to display viral antigens on the surface of Salmonella spp. Fusion proteins containing viral antigens were expressed in the oral vaccine strain, Salmonella typhi Ty21a. Surface localization was verified by immunoblotting and fluorescence-activated cell sorting. The immunogenicity of surface-displayed viral antigens on the recombinant live vaccine strain was assessed in mice inoculated intranasally and intraperitoneally. Inoculation resulted in significantly higher serum antibody level than those induced by viral antigens expressed intracellularly. Thus, this multivalent mucosal live vaccine may provide an effective means for inducing mucosal or systemic immune responses against multiple viral antigens.


Asunto(s)
Antígenos Virales/inmunología , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/inmunología , Salmonella typhi/inmunología , Vacunas Sintéticas/inmunología , Administración Intranasal , Animales , Vacunas Bacterianas/administración & dosificación , Vacunas Bacterianas/genética , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Hepacivirus/genética , Antígenos de Superficie de la Hepatitis B/genética , Immunoblotting , Inmunoglobulina G/sangre , Infusiones Parenterales , Hígado/virología , Ratones , Ratones Endogámicos BALB C , Mutagénesis , Bazo/virología , Factores de Tiempo , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética
11.
Tree Physiol ; 26(3): 377-88, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16356908

RESUMEN

We studied the effects of hyperhydricity on subcellular ultrastructure and physiology of leaves during in vitro regeneration of apple plants. Morphological, anatomical and ultrastructural differences between healthy leaf tissues obtained from greenhouse-grown plants and healthy and hyperhydric leaves obtained from shoots raised from nodal shoot explants in a bioreactor were investigated by electron microscopy and confocal laser scanning microscopy. Compared with healthy leaves, hyperhydric leaves showed abnormal, often discontinuous development of the epidermis and cuticle. Stomata were malformed. The leaf lamina appeared thickened and was characterized by poor differentiation between the palisade and spongy mesophyll tissue. Hyperhydric leaves had a significantly lower chloroplast number per cell and chloroplasts showed reduced thylakoid stacking compared with healthy leaves. Hyperhydricity resulted in a general decrease in concentrations of reduced and oxidized pyridine nucleotides, reflecting a reduction in metabolic activity. The activities of antioxidant enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were higher in hyperhydric leaves than in healthy leaves, indicating that hyperhydricity was associated with oxidative stress. Chlorophyll fluorescence measurements provided evidence of oxidative damage to the photosynthetic machinery in hyperhydric leaves: photochemical efficiency of photosystem II, effective quantum efficiency and photochemical quenching were all lower in hyperhydric leaves compared with healthy leaves.


Asunto(s)
Malus/fisiología , Malus/ultraestructura , Agua/metabolismo , Antioxidantes/metabolismo , Ascorbato Peroxidasas , Carotenoides/metabolismo , Catalasa/metabolismo , Clorofila/metabolismo , Clorofila A , Metabolismo Energético , Fluorescencia , Malus/citología , Malus/enzimología , Peroxidasas/metabolismo , Fotosíntesis , Epidermis de la Planta/enzimología , Epidermis de la Planta/fisiología , Epidermis de la Planta/ultraestructura , Hojas de la Planta/enzimología , Hojas de la Planta/fisiología , Hojas de la Planta/ultraestructura , Piridinas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
12.
Neuroscience ; 339: 644-654, 2016 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-27789382

RESUMEN

The present study investigated the effects of (-)-sesamin on motor and memory deficits in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mouse model of Parkinson's disease (PD) with l-3,4-dihydroxyphenylalanine (l-DOPA). MPTP-lesioned (30mg/kg/day, 5days) mice showed deficits in memory including habit learning memory and spatial memory, which were further aggravated by daily treatment with 25mg/kg l-DOPA for 21days. However, daily treatment with (-)-sesamin (25 and 50mg/kg) for 21days ameliorated memory deficits in an MPTP-lesioned mouse model of PD treated with l-DOPA (25mg/kg). Both (-)-sesamin doses reduced decreases in the retention latency time in the passive avoidance test, latency to fall of rotarod test and distance traveled in the open field test, and attenuated decreases in tyrosine hydroxylase (TH)-immunopositive cells, dopamine, and its metabolites in the substantia nigra-striatum. (-)-Sesamin reduced increases in the retention transfer latency time in the elevated plus-maze test and N-methyl-d-aspartate receptor (NMDAR) expression and reduced decreases in the phosphorylation of extracellular signal-regulated kinase (ERK1/2) and cyclic AMP-response element binding protein (CREB) in the hippocampus. In contrast, daily treatment with 10mg/kg l-DOPA for 21days ameliorated memory deficits in MPTP-lesioned mice, and this effect was further improved by treatment with (-)-sesamin (25 and 50mg/kg). These results suggest that (-)-sesamin protects against habit learning memory deficits by activating the dopamine neuronal system, while spatial memory deficits are decreased by its modulatory effects on the NMDAR-ERK1/2-CREB system. Accordingly, (-)-sesamin may act as an adjuvant phytonutrient for motor and memory deficits in patients with PD receiving l-DOPA.


Asunto(s)
Antiparkinsonianos/farmacología , Dioxoles/farmacología , Levodopa/farmacología , Lignanos/farmacología , Nootrópicos/farmacología , Trastornos Parkinsonianos/tratamiento farmacológico , Animales , Antiparkinsonianos/química , Reacción de Prevención/efectos de los fármacos , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Cuerpo Estriado/patología , Dioxoles/química , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Lignanos/química , Masculino , Memoria/efectos de los fármacos , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/etiología , Trastornos de la Memoria/patología , Trastornos de la Memoria/fisiopatología , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Nootrópicos/química , Trastornos Parkinsonianos/patología , Trastornos Parkinsonianos/fisiopatología , Trastornos Parkinsonianos/psicología , ARN Mensajero/metabolismo , Sustancia Negra/efectos de los fármacos , Sustancia Negra/metabolismo , Sustancia Negra/patología
13.
Int J Biol Macromol ; 85: 522-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26778161

RESUMEN

Although the peel of the hallabong (Citrus sphaerocarpa) fruit is rich in polysaccharides, which are valuable dietary ingredients for human health, it is normally wasted. The present study aimed to utilize the peel waste and identify properties it may have against breast cancer metastasis. Hallabong peel extract containing crude polysaccharides was fractionated by gel permeation chromatography to produce four different polysaccharide fractions (HBE-I, -II, -III, and -IV). The HBE polysaccharides significantly blocked tube formation of human umbilical vein vascular endothelial cells (HUVECs), at a concentration of 12.5 or 25 µg/mL. Tube formation appeared to be more sensitive to HBE-II than to other HBE polysaccharides. HBE-II also inhibited breast cancer cell migration, through downregulation of matrix metalloproteinase-9 (MMP-9) in MDA-MB-231 triple-negative breast cancer cells. Therefore, inhibition of tube formation and MMP-9-mediated migration observed in HUVEC and MDA-MB-231 cells, respectively, are likely to be important therapeutic targets in triple-negative breast cancer metastasis.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Antineoplásicos Fitogénicos/farmacología , Citrus/química , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Neoplasias de la Mama , Carbohidratos/química , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Peso Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Polisacáridos/química , Polisacáridos/aislamiento & purificación
14.
Biochim Biophys Acta ; 1163(2): 158-64, 1993 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-8387825

RESUMEN

A peroxidase was purified 98.3-fold from the culture filtrate of Pleurotus ostreatus with an overall yield of 12.4%. The molecular mass determined by gel filtration was found to be approx. 140 kDa. SDS-PAGE revealed that the enzyme consists of two identical subunits with a molecular mass of approx. 72 kDa. The pI value of this enzyme is approx. 4.3. The enzyme contains 41% carbohydrate by weight, and aspartic acid and asparagine (16.8%), and glutamic acid and glutamine (12.0%). The enzyme has the highest affinity toward synaptic acid and affinity towards various phenolic compounds containing methoxyl and p-hydroxyl groups, directly attached to the benzene ring. However, the enzyme does not react with veratryl alcohol and shows no affinity for nonphenolic compounds. The optimal reaction pH and temperature are 4.0 and 40 degrees C, respectively. The catalytic mechanism of the enzymic reaction is of the Ping-Pong type. The activity of the enzyme is competitively inhibited by high concentrations of H2O2 and its Ki value is 1.70 mM against H2O2. This enzyme contains approx. 1 mol of heme per mol of one subunit of the enzyme. The pyridine hemochrome spectrum of the enzyme indicates that the heme of P. ostreatus peroxidase is iron protoporphyrin IX. The EPR spectrum of the native peroxidase shows the presence of a high-spin ferric complex with g values at 6.102, 5.643 and 1.991.


Asunto(s)
Peroxidasa/aislamiento & purificación , Polyporaceae/enzimología , Aminoácidos/análisis , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Cinética , Lignina/metabolismo , Peso Molecular , Peroxidasa/química , Especificidad por Sustrato , Temperatura
15.
J Gen Physiol ; 117(2): 91-101, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11158163

RESUMEN

Hyperpolarization-activated cation currents (I(h)) are key determinants of repetitive electrical activity in heart and nerve cells. The bradycardic agent ZD7288 is a selective blocker of these currents. We studied the mechanism for ZD7288 blockade of cloned I(h) channels in excised inside-out patches. ZD7288 blockade of the mammalian mHCN1 channel appeared to require opening of the channel, but strong hyperpolarization disfavored blockade. The steepness of this voltage-dependent effect (an apparent valence of approximately 4) makes it unlikely to arise solely from a direct effect of voltage on blocker binding. Instead, it probably indicates a differential affinity of the blocker for different channel conformations. Similar properties were seen for ZD7288 blockade of the sea urchin homologue of I(h) channels (SPIH), but some of the blockade was irreversible. To explore the molecular basis for the difference in reversibility, we constructed chimeric channels from mHCN1 and SPIH and localized the structural determinant for the reversibility to three residues in the S6 region likely to line the pore. Using a triple point mutant in S6, we also revealed the trapping of ZD7288 by the closing of the channel. Overall, the observations led us to hypothesize that the residues responsible for ZD7288 block of I(h) channels are located in the pore lining, and are guarded by an intracellular activation gate of the channel.


Asunto(s)
Activación del Canal Iónico/fisiología , Canales Iónicos/genética , Canales Iónicos/metabolismo , Proteínas del Tejido Nervioso , Secuencia de Aminoácidos , Fármacos Cardiovasculares/farmacología , Células Cultivadas , Canales Catiónicos Regulados por Nucleótidos Cíclicos , Humanos , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización , Activación del Canal Iónico/efectos de los fármacos , Canales Iónicos/química , Riñón/citología , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida/fisiología , Técnicas de Placa-Clamp , Canales de Potasio , Estructura Terciaria de Proteína , Pirimidinas/farmacología
16.
Appl Biochem Biotechnol ; 126(1): 35-48, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16014997

RESUMEN

To find a new use of rice bran, five fungi were examined for the production of exo-biopolymer with macrophage-stimulating activity from rice bran. Among the exo-biopolymers produced from the cultures, Monascus pilosus had the most potent macrophage stimulating activity in a liquid culture rather than in a solid culture. In order to improve the yield of exo-biopolymer with macrophage-stimulating activity, a suitable medium for exo-biopolymer was tested in submerged culture of M. pilosus. The highest amount of exo-biopolymer (13.9 mg/mL) was obtained in a medium containing rice bran as an only carbon source followed by media with additional maltose and sucrose (13.8 and 13.7 mg/mL, respectively). The addition of peptone resulted in the production of high amount of exo-biopolymer (15.1 mg/mL), meanwhile the addition of ammonium chloride resulted in 264.0 microg/mL of glucosamine content. Among eight different kinds of inorganic salts tested, potassium phosphate (0.1%) was the most effective inorganic salt for the mycelial growth and exo-biopolymer production. Therefore the optimal medium composition was as follows (g/L): 20 g of rice bran, 5 g of peptone, and 1 g of KH2PO4. The optimal culture pH and time for mycelial growth and exo-biopolymer production was pH 5.0 and 25 degrees C, respectively. The maximum exo-biopolymer (20.1 mg/mL) was observed at the fourth day of cultivation. Exo-biopolymer, a crude polysaccharide fraction, mainly contained neutral sugar (81.8%) with considerable amounts of uronic acid (18.2%). Component sugar analysis showed that the active fraction consisted mainly of arabinose, galactose, glucose, which was digested from starch of rice bran during cultivation, and uronic acid (molar ratio; 0.8:1.0:0.7:0.8).


Asunto(s)
Biopolímeros/biosíntesis , Biopolímeros/farmacología , Activación de Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Monascus/metabolismo , Oryza/microbiología , Semillas/microbiología , Animales , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos ICR
17.
FEBS Lett ; 454(3): 197-200, 1999 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-10431806

RESUMEN

Phospholipase D has been recognized as playing an important role in signal transduction in many types of cells. We investigated the expression of phospholipase D during the differentiation of F9 embryonal teratocarcinoma cells. The ADP ribosylation factor-dependent phospholipase D activity, as measured by an in vitro assay, and H2O2-induced phospholipase D activity and phospholipase D protein content in whole cells were decreased during the differentiation of F9 cells induced by a combination of dibutyryl cyclic AMP and all-trans retinoic acid. In contrast, these changes were not observed when cells were induced by retinoic acid. These results suggest that down-regulation of phospholipase D protein is associated with differentiation of F9 cells to a parietal endoderm lineage.


Asunto(s)
Fosfolipasa D/biosíntesis , Teratocarcinoma/enzimología , Teratocarcinoma/patología , Animales , Antineoplásicos/farmacología , Diferenciación Celular/efectos de los fármacos , AMP Cíclico/farmacología , Regulación hacia Abajo/efectos de los fármacos , Ratones , Tretinoina/farmacología , Células Tumorales Cultivadas
18.
FEBS Lett ; 508(2): 277-81, 2001 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-11718730

RESUMEN

Phospholipase D (PLD) has been associated with necrosis. However, it is not clear whether PLD plays a causative role in this cellular process. We investigated the role of PLD in oxidative stress-induced necrosis of vascular smooth muscle cells (VSMCs). Pervanadate (hydrogen peroxide plus orthovanadate) but not hydrogen peroxide alone activated PLD in a dose- and time-dependent manner. Exposure of VSMCs to pervanadate resulted in necrosis. Pretreatment with butan-1-ol, a PLD inhibitor, attenuated both pervanadate-induced necrosis and increase of intracellular Ca(2+). Removal of extracellular Ca(2+) inhibited pervanadate-induced necrosis by 50%. These results suggest that PLD activation mediates pervanadate-induced necrosis of VSMCs, which is at least partly due to Ca(2+) toxicity.


Asunto(s)
Músculo Liso Vascular/citología , Músculo Liso Vascular/enzimología , Estrés Oxidativo , Fosfolipasa D/metabolismo , Animales , Aorta/citología , Butanoles/farmacología , Calcio/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Peróxido de Hidrógeno/farmacología , Músculo Liso Vascular/efectos de los fármacos , Necrosis , Estrés Oxidativo/efectos de los fármacos , Ratas , Factores de Tiempo , Vanadatos/farmacología
19.
J Cancer Res Clin Oncol ; 126(9): 519-28, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11003564

RESUMEN

Fibroblast growth factor (FGF), a key regulatory factor of cell growth and differentiation, is involved in embryonic development, angiogenesis, and tumorigenesis. To date, four different FGF receptors (FGFRs) have been cloned and characterized. We examined the expression of four FGFRs in human gastric cancer tissues and cell lines using Northern analysis, ribonuclease protection assay, and immunohistochemistry. The mRNAs of FGFR-1 (10/14), FGFR-2 (9/14), and FGFR-4 (9/14) were up-regulated in cancer compared with normal tissues. FGFR-3 mRNAs were barely detectable in both normal and cancer tissues. These FGFR mRNAs were co-expressed in various combinations of two or three in the same tissue. Immunohistochemistry confirmed specific staining of multiple FGFRs, except FGFR-3, in the cancer specimens. To investigate the functional significance of FGFR co-expression we examined the invasive property of SNU-16 cells, which exhibited gene amplification of FGFR-2, -3, and -4 as well as over-expression of keratinocyte growth factor receptor (KGFR), a splice variant of FGFR-2, and FGFR-4 mRNA. KGF plus acidic FGF (aFGF), KGF, and aFGF treatment enhanced the invasive potential of SNU-16 cells over the control by 100%, 107%, and 47%, respectively, indicating that neither additive nor synergistic effect was induced by stimulation with aFGF plus KGF. These results suggest that co-expression of FGFRs in various combinations may cause subtle changes in the progression of gastric cancer.


Asunto(s)
Factores de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/biosíntesis , Neoplasias Gástricas/metabolismo , Empalme Alternativo , Northern Blotting , Factor 1 de Crecimiento de Fibroblastos/farmacología , Factor 10 de Crecimiento de Fibroblastos , Factor 7 de Crecimiento de Fibroblastos , Amplificación de Genes , Sustancias de Crecimiento/farmacología , Humanos , Inmunohistoquímica , Isoformas de Proteínas , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteínas Tirosina Quinasas Receptoras/biosíntesis , Proteínas Tirosina Quinasas Receptoras/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/genética , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Receptores de Factores de Crecimiento/metabolismo , Neoplasias Gástricas/genética , Regulación hacia Arriba
20.
Carbohydr Res ; 300(3): 239-49, 1997 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-9202408

RESUMEN

A complex pectic polysaccharide (GL-4IIb2) has been isolated from the leaves of Panax ginseng C.A. Meyer, and shown to be a macrophage Fc receptor expression-enhancing polysaccharide. The primary structure of GL-4IIb2 was elucidated by composition. 1H NMR, methylation, and oligosaccharide analyses. GL-4IIb2 consisted of 15 different monosaccharides which included rarely observed sugars, such as 2-O-methylfucose, 2-O-methylxylose, apiose, 3-C-carboxy-5-deoxy-L-xylose (aceric acid, AceA), 3-deoxy-D-manno-2-octulosonic acid (Kdo), and 3-deoxy-D-lyxo-2-heptulosaric acid (Dha). Methylation analysis indicated that GL-4IIb2 comprised 34 different glycosyl linkages, such as 3,4-linked Fuc, 3- and 2,3,4-linked Rha, and 2-linked GlcA, which are characteristic of rhamnogalacturonan II (RG-II). Sequential degradation using partial acid hydrolysis indicated that GL-4IIb2 contained alpha-Rhap-(1-->5)-Kdo and Araf-(1-->5) Dha structural elements, an AceA-containing oligosaccharide, and uronic acid-rich oligosaccharide chains in addition to an alpha-(1 -->4)-galacturono-oligosaccharide chain. FABMS and methylation analyses suggested that the AceA-containing oligosaccharide was a nonasaccharide in which terminal Rha was additionally attached to position 3 of 2-linked Arap of the octasaccharide chain observed in sycamore RG-II. Component sugar and methylation analyses assumed that the uronic acid-rich oligosaccharides possessed a similar structural feature as those in sycamore RG-II. GL-4IIb2 had a larger molecular mass (11,000) than sycamore RG-II (approximately 5000).


Asunto(s)
Macrófagos/efectos de los fármacos , Panax/metabolismo , Pectinas , Plantas Medicinales , Receptores Fc/biosíntesis , Animales , Secuencia de Carbohidratos , Células Cultivadas , Macrófagos/inmunología , Datos de Secuencia Molecular , Pectinas/química , Pectinas/aislamiento & purificación , Pectinas/farmacología
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