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1.
Br Poult Sci ; 64(1): 129-136, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36103116

RESUMEN

1. Sperm are exposed to severe osmotic stress during cryopreservation, which results in impairment of fertilisation ability, including motility and viability, in poultry. Sperm osmotolerance is regulated by many extracellular factors and varies widely in birds, leading to uncertainty in the nature of the osmotic injury.2. Tail bending is a primary response resulting from cell swelling from excessive osmotic stress. However, the underlying mechanism responsible for tail bending is largely unknown. This study examined the relationship between osmotic stress and post-thaw motility, with a particular focus on the role of Na+/K+ ATPase (NKA) in the tail bending response.3. Cryopreserved sperm exhibited rapidly reduced motility when maintained at 37°C. The combination of temperature change and osmotic stress was a primary factor responsible for tail bending. This work tested a hypothesis known to be associated with post-thaw tail abnormality in other species and found that cold shock, that is not accompanied by an apoptotic response, may occur. Ouabain inhibition of Na+/K+ ATPase activity alleviated the tail bending response in fresh and post-thaw sperm.4. These results demonstrated that the combination of temperature change and osmotic stress has a primary impact on the reduction of post-thaw motility, with a particular role in NKA activity, in the tail bending response of chicken sperm. These results provide a foundation for establishing cryopreservation methodology to ensure the optimal fertilisation potential of cryopreserved chicken sperm.


Asunto(s)
Pollos , Motilidad Espermática , Masculino , Animales , Semen , Criopreservación/veterinaria , Criopreservación/métodos , Adenosina Trifosfatasas
2.
Nutr Metab Cardiovasc Dis ; 28(11): 1133-1139, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30143406

RESUMEN

AIMS: To examine the association between wine consumption and the prevalence of chronic kidney disease (CKD) and cardiovascular disease (CVD). DATA SYNTHESIS: We performed a cross-sectional logistic regression analysis of National Health and Nutrition Examination Survey (NHANES) in participants 21 years of age or older from 2003 to 2006 in a large representative study of the U.S. POPULATION: Wine consumption was categorized as none (0 glass per day), light (<1 glass per day), or moderate (≥1 glasses per day). Prevalent CKD was defined as a urine albumin/creatinine ratio (UACR) ≥30 mg/g or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. CVD was defined as history of CVD including angina, myocardial infarction, or stroke. Only 27 (0.5%) individuals reported moderate wine consumption, whereas 57.5% and 42% reported abstinence and light wine consumption, respectively. Light wine consumption was associated with a lower prevalence of CKD as opposed to abstinence in unadjusted analysis. After adjusting for demographics and CVD risk factors light wine consumption was associated with lower prevalence of CKD defined as UACR ≥30 mg/g but not with low eGFR. Furthermore, light wine consumption was associated with significantly lower rates of CVD in the general population and in subjects with CKD. The adjusted odd of CVD for those with light wine consumption was 0.72 (CI 0.52-0.99, p = 0.046) for the subjects with CKD. CONCLUSION: These data suggest that light wine consumption (compared to abstinence) is associated with lower prevalence of CKD and a lower odd of CVD in those with CKD in the U.S.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Insuficiencia Renal Crónica/epidemiología , Vino , Adulto , Albuminuria/epidemiología , Albuminuria/fisiopatología , Albuminuria/prevención & control , Abstinencia de Alcohol , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/fisiopatología , Estudios Transversales , Femenino , Tasa de Filtración Glomerular , Humanos , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Prevalencia , Pronóstico , Factores Protectores , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/prevención & control , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Estados Unidos/epidemiología , Adulto Joven
3.
Infection ; 39(3): 247-53, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21512791

RESUMEN

BACKGROUND: During 2005-2007, we experienced sporadic isolations of multidrug-resistant (MDRP) Pseudomonas aeruginosa from wards in a general hospital in Hiroshima. The objective of this study was to analyze epidemiology relationships and the mode of spread of the strains. METHODS: Clonality was assessed using pulsed-field gel electrophoresis (PFGE) and serotyping. MICs were determined using the microdilution broth method. Investigations of the affected patients' movements and environmental sampling from the affected wards were conducted. RESULTS: An abrupt increase in MDRP isolations began at the end of 2005 and ended in February 2007. A total of 25 MDRP strains were sporadically isolated from nine wards. Fourteen strains were genotypically and serologically identical. Analysis of the patients' movements identified that six of the 14 MDRP-positive patients became positive for MDRP when they were in the intensive care unit (ICU), and two became positive after the patients moved from the ICU to another nursing unit. Four MDRP strains were isolated from patients who did not stay in the ICU and were in ward E6, which had the second highest number of isolations. In July 2006, environmental sampling of the hospital identified a toilet brush in ward E6 that was contaminated with MDRP that was genotypically and serologically identical to the clinical isolates. CONCLUSIONS: Our study suggests that the sporadic increase in MDRP isolates during 2005-2007 in the general hospital in Hiroshima was due to an epidemic of an MDRP clone. Continuity and spread of infection was probably due to cross infection and contamination in the hospital with the MDRP strain.


Asunto(s)
Infección Hospitalaria/epidemiología , Farmacorresistencia Bacteriana Múltiple , Epidemias , Infecciones por Pseudomonas/epidemiología , Pseudomonas aeruginosa/aislamiento & purificación , Electroforesis en Gel de Campo Pulsado , Hospitales Generales , Humanos , Unidades de Cuidados Intensivos , Japón/epidemiología , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Serotipificación
4.
Clin Transl Oncol ; 23(4): 682-696, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32930920

RESUMEN

Day by day, the health and economical burden of cancer increases globally. Indeed it can be considered that there is ''cancer pandemic''. Blocking the renin-angiotensin system (RAS) by angiotensin-converting enzyme (ACE) inhibitors (ACEI) or angiotensin-receptor blockers (ARB) are widely used measures to treat hypertension and heart failure. It has been recently suggested the activation and blocking of RAS has been associated with various types of cancer in epidemiological and experimental studies. Various studies have shown that RAS blockage is protective in some cancers. However, although fewer, contradictory data also showed that RAS blockage is either not related or adversely related to cancer. Although the reasons for these findings are not exactly known, different types of receptors and effectors in RAS may account for these findings. In the current review, we summarize the different RAS receptors and cancer development with regard to epidemiology, and pathogenesis including cell signaling pathways, apoptosis, genetic and epigenetic factors.


Asunto(s)
Antagonistas de Receptores de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Epigénesis Genética , Neoplasias/epidemiología , Sistema Renina-Angiotensina/fisiología , Transducción de Señal , Apoptosis/fisiología , Carcinógenos/toxicidad , Proliferación Celular/fisiología , Contaminación de Medicamentos , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Hipertensión/tratamiento farmacológico , MicroARNs/fisiología , Neoplasias/etiología , Peptidil-Dipeptidasa A/genética , Sistema Renina-Angiotensina/efectos de los fármacos
5.
Science ; 242(4881): 1036-7, 1988 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-3143155

RESUMEN

The induction of immunoglobulin kappa light chain expression in 70Z/3 pre-B cells treated with bacterial lipopolysaccharide (LPS) requires the activation of the B cell-specific factor NF-kappa B, which binds to the kappa enhancer motif, GGGACTTTCC. This sequence alone can function as a tissue-specific enhancer for LPS-induced gene expression. A potent inhibitor of B lymphopoiesis [transforming growth factor-beta (TGF-beta)] was used to explore the mechanisms in the activation of kappa transcription by LPS and by interferon-gamma (IFN-gamma). TGF-beta inhibited LPS-induced kappa transcription but not the activation and in vitro binding of NF-kappa B. This indicates that NF-kappa B activation, while necessary, is not sufficient for LPS-induced kappa transcription. TGF-beta had no effect on IFN-gamma-induced kappa transcription, and NF-kappa B was not activated by IFN-gamma. These results reveal that LPS and IFN-gamma activate transcription through different mechanisms.


Asunto(s)
Linfocitos B/fisiología , Genes de Inmunoglobulinas , Cadenas kappa de Inmunoglobulina/genética , Interferón gamma/farmacología , Factores de Transcripción/fisiología , Transcripción Genética/efectos de los fármacos , Línea Celular , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica/efectos de los fármacos , Cadenas mu de Inmunoglobulina/genética , Técnicas In Vitro , Lipopolisacáridos/farmacología , Factores de Crecimiento Transformadores/farmacología
6.
Br J Cancer ; 99(9): 1442-52, 2008 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-18854835

RESUMEN

In a previous study, we showed that a novel anticancer drug, 1-(3-C-ethynyl-beta-D-ribo-pentofuranosyl)cytosine (TAS106, ECyd) increased the antitumour efficacy of X-irradiation. However, its effects on hypoxic cells in tumours remain unclarified. Here, we show that TAS106 enhances the induction of apoptosis in X-irradiated human gastric adenocarcinoma MKN45 and MKN28 cells under hypoxia in vitro. At the same time, the accumulation of HIF-1alpha observed under hypoxia was shown to be decreased to the level of normoxia in the presence of 0.1 microM TAS106. To study the function of HIF-1alpha protein in apoptosis of hypoxic cells, we employed an HIF-1alpha reductive approach using its specific antisense oligodeoxynucleotide. The reduction of HIF-1alpha gene expression dramatically enhanced X-ray-induced apoptosis in hypoxic cells. In in vivo experiments in which MKN45 cells were transplanted into severe combined immunodeficient (SCID) mice, TAS106 (0.5 mg kg(-1)) suppressed HIF-1alpha expression and subsequently reduced the area of the hypoxic region in the tumour and enhanced the induction of apoptosis in the hypoxic region when combined with 2 Gy of X-irradiation. These results suggest the possibility that TAS106 acts as a potent radiosensitiser through the inhibition of HIF-1alpha expression and can be a useful agent against radiotherapy-resistant hypoxic cells in solid tumours.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Fármacos Sensibilizantes a Radiaciones/farmacología , Animales , Ciclo Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ratones , Ratones SCID , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , Oligonucleótidos Antisentido/farmacología , Transcripción Genética/efectos de los fármacos , Uridina Quinasa/genética , Uridina Quinasa/fisiología , Factor A de Crecimiento Endotelial Vascular/genética , Terapia por Rayos X
7.
Rev Sci Instrum ; 89(2): 023111, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29495866

RESUMEN

Newly designed Lyman-alpha absorption cells for imaging hydrogen planetary corona were characterized using an ultra high resolution Fourier transform spectrometer installed on the DESIRS (Dichroïsme Et Spectroscopie par Interaction avec le Rayonnement Synchrotron) beamline of Synchrotron SOLEIL in France. The early absorption cell installed in the Japanese Mars orbiter NOZOMI launched in 1998 had not been sufficiently optimized due to its short development time. The new absorption cells are equipped with the ability to change various parameters, such as filament shape, applied power, H2 gas pressure, and geometrical configuration. We found that the optical thickness of the new absorption cell was ∼4 times higher than the earlier one at the center wavelength of Lyman-alpha absorption, by optimizing the condition to promote thermal dissociation of H2 molecules into two H atoms on a hot tungsten filament. The Doppler temperature of planetary coronas could be determined with an accuracy better than 100 K with the performance of the newly developed absorption cell.

8.
J Natl Cancer Inst ; 90(20): 1563-8, 1998 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-9790550

RESUMEN

BACKGROUND: The presence of autoantibodies to p53 protein has been associated with the presence of p53 (also known as TP53) gene mutations in primary tumors and with poor prognosis. This study was undertaken to determine the clinical significance of p53 autoantibodies in patients with non-small-cell lung cancer (NSCLC). METHODS: We studied 188 consecutive patients with NSCLC who underwent pulmonary resection and for whom preoperative serum was available. The presence of p53 autoantibodies, detected by use of two amino-terminal and two carboxy-terminal peptides (20-30 mers) as antigens and an enzyme-linked immunosorbent assay, was related to various clinicopathologic parameters and to overexpression of p53 protein in the primary tumor. For 22 patients who had p53 autoantibodies before surgery, we also examined sera taken during postoperative follow-up. Reported P values are two-sided. RESULTS: Autoantibodies to p53 protein were detected in 38 patients. Patients with squamous cell carcinoma, those with more advanced disease (stage III-IV), and those with tumors that overexpressed p53 had a significantly higher incidence of p53 autoantibodies (P = .05,.0079, and .02, respectively). In all but one of the patients with postoperative serum samples, the antibody titer declined after surgery; however, there was no relationship between clinical course and this change in antibody titer. In addition, there was no relationship between the presence of p53 autoantibodies and overall survival in 171 patients who underwent potentially curative resection (P = .28); however, 13 patients with autoantibodies to amino-terminal peptides had a worse overall survival (P = .02). CONCLUSIONS: In NSCLC, the incidence of p53 autoantibodies is associated with histologic type, stage, and p53 overexpression--but not with patient survival. Our data do not support the clinical utility of p53 autoantibodies as diagnostic or prognostic markers in patients with NSCLC.


Asunto(s)
Autoanticuerpos/sangre , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Neoplasias Pulmonares/inmunología , Proteína p53 Supresora de Tumor/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Núcleo Celular/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Proteína p53 Supresora de Tumor/metabolismo
9.
Kyobu Geka ; 59(13): 1213-6, 2006 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-17163217

RESUMEN

A 61-year-old woman was admitted due to severe coughing. Chest X-ray revealed a mass in the right lower lung field at standing position and in the right upper lung field at supine position. A position of the mass changed with change in her posture because of lobar torsion. Bronchoscopic biopsy of the polypoid tumor obstructing the right upper bronchus revealed adenocarcinoma. She had hypertrophic osteoarthropathy simultaneously. Right pneumonectomy was performed. Postoperative course has been uneventful for 3 years.


Asunto(s)
Adenocarcinoma/complicaciones , Adenocarcinoma/cirugía , Enfermedades Pulmonares/etiología , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/cirugía , Osteoartropatía Hipertrófica Secundaria/etiología , Femenino , Humanos , Enfermedades Pulmonares/cirugía , Persona de Mediana Edad , Neumonectomía , Anomalía Torsional/etiología , Anomalía Torsional/cirugía , Resultado del Tratamiento
10.
Drug Res (Stuttg) ; 66(12): 628-632, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27643410

RESUMEN

Background: Hypertension is a common complication in patients with gout and/or hyperuricemia. Besides, hyperuricemia is a risk factor of gout as well as ischemic heart disease in hypertensive patients. Moreover, the risk of gout is modified by antihypertensive drugs. However, it remains unclear how antihypertensive agents affect uric acid metabolism. Purpose: In the present study, we investigated the uric acid metabolism in treated hypertensive patients to find out whether any of them would influence serum levels of uric acid. Patients and methods: 751 hypertensive patients (313 men and 438 women) under antihypertensive treatment were selected. Blood pressure (BP), serum uric acid (SUA) and serum creatinine (Scr) were measured and evaluated statistically. Results: In patients treated with diuretics, beta-blockers and/or alpha-1 blockers SUA levels were significantly higher than in patients who were not taking these drugs. Besides, the estimated glomerular filtration rate (eGFR) in patients treated with diuretics, beta-blockers and/or alpha-1 blockers was negatively correlated with SUA level. There were gender differences in the effects of beta-blockers and alpha-1 blockers. Multiple regression analysis indicated that both diuretics and beta-blockers significantly contributed to hyperuricemia in patients with medication for hypertension. Conclusion: Diuretics, beta-blockers and alpha-1 blockers reduced glomerular filtration rate and raised SUA levels. Calcium channel blockers, ACE inhibitors and angiotensin receptor blockers, including losartan, did not increase SUA levels.


Asunto(s)
Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Ácido Úrico/metabolismo , Antagonistas de Receptores Adrenérgicos alfa 1/uso terapéutico , Antagonistas Adrenérgicos beta/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Bloqueadores de los Canales de Calcio/uso terapéutico , Estudios de Cohortes , Creatinina/sangre , Estudios Transversales , Diuréticos/uso terapéutico , Quimioterapia Combinada/métodos , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Hipertensión/sangre , Hipertensión/metabolismo , Losartán/uso terapéutico , Masculino , Ácido Úrico/sangre
11.
Drug Res (Stuttg) ; 66(5): 270-4, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26909689

RESUMEN

BACKGROUND: Although urate impaired the endothelial function, its underlying mechanism remains unknown. We hypothesized that urate impaired nitric oxide (NO) production in human umbilical vein endothelial cells (HUVECs) via activation of uric acid transporters (UATs). PURPOSE AND METHOD: In the present study, we studied effects of urate on NO production and eNOS protein expression in HUVEC cells in the presence and absence of urate lowering agents using molecular biological and biochemical assays. RESULTS: HUVECs expressed the 4 kinds of UATs, URATv1, ABCG2, MRP4 and MCT9. Exposure to urate at 7 mg/dl for 24 h significantly reduced production of NO. Pretreatment with benzbromarone, losartan or irbesartan normalized NO production. The same exposure resulted in dephosphorylation of endothelial NO synthase (eNOS) in HUVECs. Again pretreatment with benzbromarone, losartan or irbesartan abolished this effect. CONCLUSION: Urate reduced NO production by impaired phosphorylation of eNOS in HUVEC via activation of UATs, which could be normalized by urate lowering agents.


Asunto(s)
Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico/metabolismo , Ácido Úrico/farmacología , Uricosúricos/farmacología , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/antagonistas & inhibidores , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Benzbromarona/farmacología , Compuestos de Bifenilo/farmacología , Células Cultivadas , Proteínas Facilitadoras del Transporte de la Glucosa/antagonistas & inhibidores , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Irbesartán , Losartán/farmacología , Transportadores de Ácidos Monocarboxílicos/antagonistas & inhibidores , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/metabolismo , Fosforilación , Tetrazoles/farmacología
12.
Biochim Biophys Acta ; 432(3): 292-9, 1976 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-178378

RESUMEN

When deoxyribonucleoprotein-proflavine complexes were studied by electron spin-resonance spectroscopy following gamma-irradiation, it was found that stable free radicals were not formed at random on the complex but were preferentially located on proflavine. Since proflavine intercalalated to DNA bases serves as a final acceptor of electrons liberated by ionization, the result of our experiment was regarded as suggesting that the electron transfer from the protein moiety to the DNA moiety occurred in the irradiated deoxyribonucleoprotein.


Asunto(s)
ADN/efectos de la radiación , Desoxirribonucleoproteínas/efectos de la radiación , Nucleoproteínas/efectos de la radiación , Efectos de la Radiación , Animales , Sitios de Unión , Bovinos , Espectroscopía de Resonancia por Spin del Electrón , Transporte de Electrón , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica , Timo
13.
J Gen Physiol ; 56(6): 768-82, 1970 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-5483106

RESUMEN

The effects of amino acids on the labellar hair chemosensory cells were examined with two kinds of flies (the fleshfly, Boettcherisca peregrina, and the blowfly, Phormia regina). As a result of this examination, the effects of amino acids were divided into four main classes. Amino acids in class 1 did not stimulate any chemoreceptor cell. Amino acids in class 2 inhibited nonspecifically the discharges from three kinds of chemosensory cells. Amino acids in class 3 stimulated the salt receptor cell. Amino acids in class 4 stimulated the sugar receptor cell. A possibility that a fourth neuron in the labellar hair chemosensory cell might be a protein or an amino acid receptor cell was eliminated.


Asunto(s)
Aminoácidos/farmacología , Células Quimiorreceptoras/efectos de los fármacos , Dípteros/efectos de los fármacos , Cabello/efectos de los fármacos , Animales , Células Quimiorreceptoras/fisiología , Electrofisiología , Sacarosa/farmacología , Agua/farmacología
14.
Leukemia ; 14(2): 299-306, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10673748

RESUMEN

The mechanism of apoptosis induced by 2-chloro-2'-deoxyadenosine (2CdA) in human leukemia cell line MOLT-4 was investigated. 2CdA induced increases of 3'-OH ends of genomic DNA, ladder-like DNA fragmentation and phosphatidylserine translocation to the outer membrane, which are apoptotic characteristics. These apoptotic phenomena induced by 2CdA were inhibited by cycloheximide (CHX; a protein synthesis inhibitor), deoxycytidine (dC; a substrate of deoxycytidine kinase), acetyl Ile-Glu-Thr-Asp aldehyde (Ac-IETD-CHO; a caspase-8 inhibitor) and acetyl Asp-Glu-Val-Asp aldehyde (Ac-DEVD-CHO; a caspase-3 inhibitor). The protein synthesis-dependent expression of Fas and Fas ligand (Fas-L) was detected by treatment with 2CdA. The proteolytic processing of procaspases-8 and -3 to produce active fragments, caspases-8 (p18) and -3 (p17), respectively, was observed after treatment with 2CdA, and suppressed by cycloheximide. Increases in the activities of caspases-8 and -3 were observed after 2CdA treatment. Their activation was also dependent on protein synthesis. These results indicated that 2CdA-induced apoptosis was triggered by phosphorylation of 2CdA followed by the protein synthesis-dependent expression of Fas and Fas-L and activation of caspases-8 and -3.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Cladribina/farmacología , Leucemia/tratamiento farmacológico , Leucemia/metabolismo , Receptor fas/efectos de los fármacos , Antineoplásicos/antagonistas & inhibidores , Western Blotting , Caspasa 3 , Caspasa 8 , Caspasa 9 , Inhibidores de Caspasas , Cladribina/antagonistas & inhibidores , Cicloheximida/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Fragmentación del ADN , ADN de Neoplasias , Desoxicitidina/farmacología , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Fluorometría , Humanos , Etiquetado Corte-Fin in Situ , Leucemia/enzimología , Oligopéptidos/farmacología , Fosforilación/efectos de los fármacos , Células Tumorales Cultivadas
15.
Clin Cancer Res ; 4(9): 2195-200, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9748139

RESUMEN

The purpose of this study was to determine the angiogenic profile of human esophageal carcinomas. The expression of vascular endothelial growth factor (VEGF) was examined in 6 esophageal carcinoma cell lines and 119 human esophageal carcinoma tissues by Northern blot analysis and immunohistochemistry, respectively. Immunohistochemistry using antibodies against CD34 (endothelial cell specific) was carried out on archival specimens, and microvessels were quantitated by counting vessels in a x200 field in the most vascular area of the tumor. All of the cell lines constitutively expressed VEGF mRNA at various levels. A total of 71 of 119 (59.7%) tumors showed intense VEGF immunoreactivity in the cytoplasm of cancer cells. Vessel count was significantly higher in the VEGF-positive tumors than it was in the VEGF-negative tumors. VEGF expression correlated with the depth of tumor invasion, tumor stage, venous invasion, and lymphatic invasion. The survival rate of patients with high vessel density in the tumor was significantly worse than that of patients with low vessel density in the tumor. There was a tendency for poorer prognosis in the group with VEGF-positive tumors compared with that of the group with VEGF-negative tumors. Overall, these results suggest that VEGF is associated with tumor progression by stimulating angiogenesis in human esophageal carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/irrigación sanguínea , Carcinoma de Células Escamosas/metabolismo , Factores de Crecimiento Endotelial/biosíntesis , Neoplasias Esofágicas/irrigación sanguínea , Neoplasias Esofágicas/metabolismo , Linfocinas/biosíntesis , Neovascularización Patológica/metabolismo , Northern Blotting , Progresión de la Enfermedad , Humanos , Pronóstico , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
16.
Exp Hematol ; 29(2): 174-82, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11166456

RESUMEN

OBJECTIVE: In an attempt to maintain and expand human stem cells, many investigators have used xenogeneic, especially murine, stromal cells and fetal calf serum. Because of the possible transmission of infectious diseases, however, the safety of the delivery of grafts expanded in culture using xenogeneic cells and serum has been debated. Using primary human marrow stromal cells, we established a novel serum-free culture system to expand human primitive progenitors and transplantable stem cells. MATERIALS AND METHODS: Cord blood CD34(+) cells were cultured on a monolayer of human primary marrow stromal cells in the presence of thrombopoietin (TPO), flt3/flk2 ligand (FL), and/or stem cell factor (SCF) under serum-free conditions. After 2 or 4 weeks of culture, cells were examined for clonogenic progenitors and severe combined immunodeficient disorder (SCID) mouse-reconstituting cells (SRC). RESULTS: In the presence of TPO, FL, and SCF, marrow stromal cells supported more than a 100- and 1,000-fold expansion of CD34(+) cells and colony-forming units in culture after 2 and 4 weeks of incubation, respectively. In addition, cobblestone area-forming cells were expanded more than 18- and 60-fold after 2 and 4 weeks of culture, respectively. Furthermore, SRC assay demonstrated augmented engraftment by cultured cells. CONCLUSION: This ex vivo expansion system should prove valuable in clinical settings in which stromal cells are available from recipients or stem cell donors.


Asunto(s)
Células de la Médula Ósea/citología , Técnicas de Cocultivo/métodos , Medio de Cultivo Libre de Suero , Sangre Fetal/citología , Células Madre Hematopoyéticas/citología , Células del Estroma/citología , Enfermedad Aguda , Animales , Antígenos CD34/análisis , Ensayo de Unidades Formadoras de Colonias , Citometría de Flujo , Hematopoyesis , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucemia/patología , Antígenos Comunes de Leucocito/análisis , Proteínas de la Membrana/farmacología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Factor de Células Madre/farmacología , Trombopoyetina/farmacología
17.
FEBS Lett ; 467(2-3): 253-8, 2000 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-10675549

RESUMEN

Stimulation of bovine polymorphonuclear leukocytes (PMN) with serum-opsonized zymosan (sOZ) induced the activation of p38 mitogen-activated protein kinase (MAPK), protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3-K) and sOZ-induced O(2)(-) production was significantly attenuated by their inhibitors (SB203580 for p38 MAPK, GF109203X for PKC and wortmannin for PI3-K). They caused significant attenuation of sOZ-induced phosphorylation of p47phox as well. Flow cytometric analysis, however, revealed that SB203580 and wortmannin attenuated phagocytosis, but GF109203X facilitated it. The results suggest that p38 MAPK and PI3-K participated in both signaling pathways of NADPH oxidase activation (O(2)(-) production) and phagocytosis, and PKC participated in the signaling pathway of NADPH oxidase activation alone.


Asunto(s)
Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Proteínas Quinasas Activadas por Mitógenos , NADPH Oxidasas/metabolismo , Neutrófilos/enzimología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteína Quinasa C/metabolismo , Animales , Bovinos , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Fagocitosis/efectos de los fármacos , Transducción de Señal , Zimosan , Proteínas Quinasas p38 Activadas por Mitógenos
18.
Free Radic Biol Med ; 23(7): 1073-7, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9358251

RESUMEN

In the present study we demonstrated the effects of the spin-trapping agent alpha-phenyl-N-tert-butylnitrone (PBN) on the in vitro development of rat embryos at the early stage. In rat embryos, PBN increased the speed of the first cleavage and had no toxicity during pregnancy after embryo culture. These results showed that reactive oxygen species (ROIs) that were formed by activating molecular oxygens through redox reactions regulated the speed of development for early-stage embryos. Thus, PBN caused a decrease in the level of ROIs and toxicity and an in increase in the level of the development of rat embryos. On the other hand, PBN could not decrease the 2-cell block in vitro nor increase the blastulation rate, in contrast to the fact that a scavenger of superoxide anions, SOD, is effective in doing so for mouse embryos. From these results it was concluded that free radicals play an important role in the in vitro development of rat embryos at the early stage, but play no role in the decrease of the 2-cell block or their blastulation rate. It should be noted that PBN had no toxicity for embryonic development at the 2-cell stage.


Asunto(s)
Blastocisto/efectos de los fármacos , Óxidos de Nitrógeno/farmacología , Animales , Técnicas de Cultivo , Óxidos N-Cíclicos , Desarrollo Embrionario y Fetal/efectos de los fármacos , Femenino , Radicales Libres , Embarazo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Marcadores de Spin , Superóxido Dismutasa/metabolismo
19.
Free Radic Biol Med ; 21(6): 755-61, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8902521

RESUMEN

In the present study we demonstrated the protective effects of the spin-trapping agent alpha-phenyl-tert-butyl nitrone (PBN) against fulminant hepatitis with jaundice in LEC rats. In LEC rats an excess amount of copper is accumulated in the liver and causes hepatitis with severe jaundice. PBN was subcutaneously administered every 2 d at the concentration of 128 mg/kg, beginning with 13-week-old rats and continuing for 17 weeks. PBN prevented the loss of body weight, reduced death rate, and suppressed the increase in GTP and GOT values reflecting hepatic cell destruction. Ocular inspection also confirmed the suppressive effects of PBN on jaundice. In parallel with these phenomena, the amounts of thiobarbituric acid-reactive substances (TBARS) in livers of PBN-administered rats were found to be lower than those of non-PBN-administered rats. Little histological changes were observed in PBN-administered rats in comparison with non-PBN-administered rats. The protective effect of PBN on the formation of oxidative damage in liver DNA was observed but not so remarkable as that on lipid peroxidation. From these results, it was concluded that PBN had the liver-protective effects against fulminant hepatitis with jaundice. This suggested that free radicals play an important role in abnormally accumulated copper-induced liver injury and that PBN potentially has therapeutic value for the treatment of hepatitis.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Cobre , Ictericia/prevención & control , Óxidos de Nitrógeno/uso terapéutico , Marcadores de Spin , 8-Hidroxi-2'-Desoxicoguanosina , Envejecimiento , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Óxidos N-Cíclicos , ADN/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Ictericia/inducido químicamente , Peroxidación de Lípido , Hígado/metabolismo , Ratas , Ratas Mutantes , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Pérdida de Peso
20.
Antioxid Redox Signal ; 1(1): 113-21, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-11225728

RESUMEN

To clarify activation mechanisms of stress-activated protein kinase/C-Jun N-terminal kinase (SAPK/JNK) during oxidative stress, the roles of phosphatidylinositol 3-kinase (PI 3-kinase), concentration of intracellular calcium ([Ca2+]i), and cyclic AMP-dependent kinase (PKA) in hydrogen peroxide (H2O2)-induced SAPK/JNK activation were examined in Chinese hamster V79 cells. SAPK/JNK was dose-dependently activated after H2O2 treatment (from 10 microM to 1 mM), and a PI 3-kinase inhibitor (wortmaninn), intracellular calcium chelator (BAPTA-AM), and PKA activator (dibutyl cyclic AMP and forskolin) inhibited this activation. An increase in [Ca2+], was observed after treatment with H2O2. Immunoprecipitation revealed that a PI 3-kinase regulatory subunit, p85alpha, was associated with insulin receptor substance 1 (IRS-1) phosphorylated by H2O2 treatment. Furthermore, the formation of this complex of p85alpha and phospho-IRS-1 was abolished by the presence of BAPTA-AM but not forskolin. These results indicated that the PI 3-kinase activated through phosphorylation of IRS-1 upstream of SAPK/JNK after H2O2 treatment of V79 cells and that [Ca2+]i was a regulation factor for phosphorylation of IRS-1.


Asunto(s)
Calcio/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Peróxido de Hidrógeno/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Androstadienos/farmacología , Animales , Bucladesina/farmacología , Línea Celular , Quelantes/farmacología , Colforsina/farmacología , Cricetinae , Cricetulus , Ácido Egtácico/análogos & derivados , Ácido Egtácico/farmacología , Activación Enzimática , Humanos , Immunoblotting , Proteínas Sustrato del Receptor de Insulina , Proteínas Quinasas JNK Activadas por Mitógenos , Fosfatidilinositol 3-Quinasas/inmunología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosfoproteínas/metabolismo , Fosforilación , Pruebas de Precipitina , Wortmanina
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