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1.
Gene Ther ; 23(1): 50-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26241176

RESUMEN

Combination therapy of carbon-ion beam with the far upstream element-binding protein (FBP)-interacting repressor, FIR, which interferes with DNA damage repair proteins, was proposed as an approach for esophageal cancer treatment with low side effects regardless of TP53 status. In vivo therapeutic antitumor efficacy of replication-defective adenovirus (E1 and E3 deleted adenovirus serotype 5) encoding human FIR cDNA (Ad-FIR) was demonstrated in the tumor xenograft model of human esophageal squamous cancer cells, TE-2. Bleomycin (BLM) is an anticancer agent that introduces DNA breaks. The authors reported that Ad-FIR involved in the BLM-induced DNA damage repair response and thus applicable for other DNA damaging agents. To examine the effect of Ad-FIR on DNA damage repair, BLM, X-ray and carbon-ion irradiation were used as DNA damaging agents. The biological effects of high linear energy transfer (LET) radiotherapy used with carbon-ion irradiation are more expansive than low-LET conventional radiotherapy, such as X-rays or γ rays. High LET radiotherapy is suitable for the local control of tumors because of its high relative biological effectiveness. Ad-FIR enhanced BLM-induced DNA damage indicated by γH2AX in vitro. BLM treatment increased endogenous nuclear FIR expression in TE-2 cells, and P27Kip1 expression was suppressed by TP53 siRNA and BLM treatment. Further, Ad-FIRΔexon2, a dominant-negative form of FIR that lacks exon2 transcriptional repression domain, decreased Ku86 expression. The combination of Ad-FIR and BLM in TP53 siRNA increased DNA damage. Additionally, Ad-FIR showed synergistic cell toxicity with X-ray in vitro and significantly increased the antitumor efficacy of carbon-ion irradiation in the xenograft mouse model of TE-2 cells (P=0.03, Mann-Whitney's U-test) and was synergistic with the sensitization enhancement ratio (SER) value of 1.15. Therefore, Ad-FIR increased the cell-killing activity of the carbon-ion beam that avoids late-phase severe adverse effects independently of the TP53 status in vitro. Our findings indicated the feasibility of the combination of Ad-FIR with DNA damaging agents for future esophageal cancer treatment.


Asunto(s)
Adenoviridae/genética , Neoplasias Esofágicas/tratamiento farmacológico , Radioterapia de Iones Pesados/métodos , Proteínas de Unión al ARN/metabolismo , Proteínas Represoras/metabolismo , Proteína p53 Supresora de Tumor/genética , Animales , Bleomicina/farmacología , Línea Celular Tumoral , Terapia Combinada , Daño del ADN/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Técnicas de Silenciamiento del Gen , Vectores Genéticos , Células HeLa , Humanos , Ratones , Ratones Endogámicos BALB C , Factores de Empalme de ARN , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteínas de Unión al ARN/genética , Proteínas Represoras/genética , Proteína p53 Supresora de Tumor/metabolismo , Rayos X , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Gene Ther ; 22(4): 297-304, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25588744

RESUMEN

Far-upstream element-binding protein-interacting repressor (FIR) is a transcription factor that inhibits c-Myc expression and has been shown to have antitumor effects in some malignancies. Here, we evaluated the antitumor effects of FIR using fusion gene-deleted Sendai virus (SeV/ΔF) as a nontransmissible vector against head and neck squamous cell carcinoma (HNSCC). Using in vitro and in vivo xenograft mouse models, we observed efficient expression of green fluorescent protein (GFP) following transduction with the SeV/ΔF vector encoding GFP (GFP-SeV/ΔF) into HNSCC cells. In vitro and in vivo studies revealed that administration of the FIR-encoded SeV/ΔF (FIR-SeV/ΔF) vector exerted significant antitumor effects, suppressed c-Myc expression and induced apoptosis in HNSCC. Additionally, the antitumor effects of FIR or the expression of GFP following administration of the FIR- or GFP-SeV/ΔF vector, respectively, were dependent on the multiplicity of infection or titer. Furthermore, the SeV/ΔF vector itself had no cytotoxic effects. Therefore, the SeV/ΔF vector may be safe and useful for the treatment of HNSCC, allowing for high-titer SeV/ΔF vector administration for anticancer gene therapy. In addition, SeV/ΔF vector-mediated FIR gene therapy demonstrated effective tumor suppression in HNSCC, suggesting that this therapy may have the potential for clinical use as a novel strategy for HNSCC treatment.


Asunto(s)
Factores de Intercambio de Guanina Nucleótido/metabolismo , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/terapia , Virus Sendai/metabolismo , Animales , Línea Celular , Femenino , Técnicas de Transferencia de Gen , Terapia Genética , Vectores Genéticos , Neoplasias de Cabeza y Cuello/genética , Xenoinjertos , Humanos , Ratones , Trasplante de Neoplasias , Proteínas Proto-Oncogénicas c-myc/metabolismo
3.
Clin Exp Allergy ; 44(3): 450-7, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24372664

RESUMEN

BACKGROUND: Schizophyllum commune is one of the causative agents of basidiomycosis including disorders such as allergic bronchopulmonary mycosis, allergic fungal sinusitis, and mucoid impaction of bronchi, the incidence of those of which has been increasing. These mycoses are difficult to diagnose because only a limited number of diagnostic tools are currently available. The biggest problem is that no specific antigens of S. commune have been identified to enable serodiagnosis of the disease. OBJECTIVE: In this study, we attempted to identify a major antigen of S. commune to establish a reliable serodiagnostic method. METHODS: We used mass spectrometry to identify an antigen that reacted with the serum of a patient with allergic bronchopulmonary mycosis caused by S. commune. The protein was expressed in Escherichia coli, highly purified, and the patient sera IgG and IgE titres against the protein were determined by enzyme-linked immunosorbent assay. RESULTS: The protein identified as a major antigen of S. commune was named Sch c 1; it was a homolog of glucoamylase. The IgG and IgE titres against Sch c 1 in patient sera were significantly higher than those in healthy volunteer sera (P < 0.01). CONCLUSIONS AND CLINICAL RELEVANCE: Sch c 1 is recognized by the host immune system of patients as an antigen/allergen. The purified glucoamylase Sch c 1 is a promising candidate antigen for the serodiagnosis of S. commune-induced mycosis.


Asunto(s)
Alérgenos/inmunología , Antígenos Fúngicos/inmunología , Glucano 1,4-alfa-Glucosidasa/inmunología , Micosis/inmunología , Schizophyllum/inmunología , Alérgenos/química , Secuencia de Aminoácidos , Anticuerpos Antifúngicos/sangre , Anticuerpos Antifúngicos/inmunología , Antígenos Fúngicos/química , Reacciones Cruzadas/inmunología , Glucano 1,4-alfa-Glucosidasa/química , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Datos de Secuencia Molecular , Micosis/sangre , Aspergilosis Pulmonar/inmunología , Schizophyllum/enzimología , Alineación de Secuencia
4.
Neurourol Urodyn ; 30(1): 102-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20658542

RESUMEN

AIMS: It is usually difficult to distinguish between idiopathic Parkinson's disease (PD) and parkinsonian-type multiple system atrophy (MSA-P) in the early stage. However, it is important to make a careful early-stage diagnosis. Therefore, we determined whether an examination of pelvic organ dysfunction would be helpful to distinguish between PD and MSA-P. METHODS: We recruited 61 patients with PD and 54 patients with MSA-P who were examined at our neurology clinic. The mean ages of the patients with PD and MSA-P were 67 and 64 years, respectively. The mean disease duration of both groups was 3.2 years. We administered a questionnaire on pelvic organ dysfunction to the PD and MSA-P groups. The questionnaire had sections focusing on bladder, bowel, and sexual function. Dysfunction, as described in the responses, was evaluated as normal, mild (>once a month), moderate (>once a week), or severe (>once a day). The Mann-Whitney U-test was used for statistical analysis. RESULTS: Compared with the PD group, the prevalence and severity of pelvic dysfunction in the MSA-P group was significantly higher for urinary urgency (MSA-P 76%, PD 58%, P<0.05), retardation in initiating urination (79%, 48%, P<0.05), prolongation in urination (79%, 72%, P<0.05), and constipation (58%, 31%, P<0.05). The quality-of-life index among pelvic organ dysfunctions indicated that urinary and bowel function was significantly more impaired in the MSA-P group than in the PD group. CONCLUSIONS: Urinary urgency, retardation in initiating urination, prolongation in urination, and constipation are more prevalent and severe in MSA-P compared to PD.


Asunto(s)
Estreñimiento/etiología , Atrofia de Múltiples Sistemas/complicaciones , Enfermedad de Parkinson/complicaciones , Pelvis/fisiopatología , Enfermedades de la Vejiga Urinaria/etiología , Anciano , Estreñimiento/fisiopatología , Diagnóstico Diferencial , Diagnóstico Precoz , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atrofia de Múltiples Sistemas/fisiopatología , Enfermedad de Parkinson/fisiopatología , Prevalencia , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Enfermedades de la Vejiga Urinaria/fisiopatología
5.
J Exp Med ; 193(4): 417-26, 2001 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-11181694

RESUMEN

IkappaB kinase (IKK) alpha and beta phosphorylate IkappaB proteins and activate the transcription factor, nuclear factor (NF)-kappaB. Although both are highly homologous kinases, gene targeting experiments revealed their differential roles in vivo. IKKalpha is involved in skin and limb morphogenesis, whereas IKKbeta is essential for cytokine signaling. To elucidate in vivo roles of IKKalpha in hematopoietic cells, we have generated bone marrow chimeras by transferring control and IKKalpha-deficient fetal liver cells. The mature B cell population was decreased in IKKalpha(-/-) chimeras. IKKalpha(-/-) chimeras also exhibited a decrease of serum immunoglobulin basal level and impaired antigen-specific immune responses. Histologically, they also manifested marked disruption of germinal center formation and splenic microarchitectures that depend on mature B cells. IKKalpha(-/-) B cells not only showed impairment of survival and mitogenic responses in vitro, accompanied by decreased, although inducible, NF-kappaB activity, but also increased turnover rate in vivo. In addition, transgene expression of bcl-2 could only partially rescue impaired B cell development in IKKalpha(-/-) chimeras. Taken together, these results demonstrate that IKKalpha is critically involved in the prevention of cell death and functional development of mature B cells.


Asunto(s)
Linfocitos B/citología , Proteínas de Unión al ADN/genética , Proteínas I-kappa B , FN-kappa B/antagonistas & inhibidores , Animales , Linfocitos B/inmunología , Células de la Médula Ósea , Diferenciación Celular , Proteínas de Unión al ADN/metabolismo , Centro Germinal , Recuento de Linfocitos , Ratones , Ratones Mutantes , Inhibidor NF-kappaB alfa , Bazo , Quimera por Trasplante , Trasplantes
6.
Br J Cancer ; 103(2): 223-31, 2010 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-20551957

RESUMEN

BACKGROUND: Intracellular phosphoprotein activation significantly regulates cancer progression. However, the significance of circulating phosphoproteins in the blood remains unknown. We investigated the serum phosphoprotein profile involved in pancreatic cancer (PaCa) by a novel approach that comprehensively measured serum phosphoproteins levels, and clinically applied this method to the detection of PaCa. METHODS: We analysed the serum phosphoproteins that comprised cancer cellular signal pathways by comparing sera from PaCa patients and benign controls including healthy volunteers (HVs) and pancreatitis patients. RESULTS: Hierarchical clustering analysis between PaCa patients and HVs revealed differential pathway-specific profiles. In particular, the components of the extracellular signal-regulated kinase (ERK) signalling pathway were significantly increased in the sera of PaCa patients compared with HVs. The positive rate of p-ERK1/2 (82%) was found to be superior to that of CA19-9 (53%) for early stage PaCa. For the combination of these serum levels, the area under the receiver-operator characteristics curves was showing significant ability to distinguish between the two populations in independent validation set, and between cancer and non-cancer populations in another validation set. CONCLUSION: The comprehensive measurement of serum cell signal phosphoproteins is useful for the detection of PaCa. Further investigations will lead to the implementation of tailor-made molecular-targeted therapeutics.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Pancreáticas/diagnóstico , Fosfoproteínas/sangre , Transducción de Señal , Análisis por Conglomerados , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Quinasas Quinasa Quinasa PAM/metabolismo , Masculino , Neoplasias Pancreáticas/sangre , Pancreatitis/sangre , Fosforilación , Proteómica/métodos
7.
J Chemother ; 19(6): 709-15, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18230555

RESUMEN

5-fluorouracil (5-FU) is a basic agent used in chemotherapy. The aim of this study is to investigate the gene expression of 5-FU anabolic and catabolic enzymes in hepatocellular carcinoma (HCC) and non-tumor tissue, respectively to increase our knowledge of resistant mechanisms to 5-FU in HCC. The relative mRNA level of orotate phosphoribosyltransferase (OPRT), ribonucleotide reductase (RNR), dihydropyrimidine dehydrogenase (DPD) and target enzyme thymidylate synthase (TS), were analyzed in 30 matched samples of HCC (T) and non-tumor tissue (NT) using quantitative RT-PCR. The expression of OPRT, RNR-M1, RNR-M2 and TS is significantly higher in T compared with in NT (1.3-fold increase, 1.6-fold, 7.1-fold, 1.9-fold, respectively), but that of DPD showed no difference between T and NT. Our results show that HCC should not be treated with 5-FU alone because of its instability in liver.


Asunto(s)
Carcinoma Hepatocelular/enzimología , Fluorouracilo/metabolismo , Neoplasias Hepáticas/enzimología , Hígado/enzimología , Dihidrouracilo Deshidrogenasa (NADP)/metabolismo , Femenino , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Orotato Fosforribosiltransferasa/metabolismo , Ribonucleótido Reductasas/metabolismo , Timidilato Sintasa/metabolismo
8.
Oncogene ; 18(23): 3471-80, 1999 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-10376525

RESUMEN

We have identified and characterized a new calcium/calmodulin (Ca2+/CaM) dependent protein kinase termed death-associated protein kinase 2 (DAPK2) that contains an N-terminal protein kinase domain followed by a conserved CaM-binding domain with significant homologies to those of DAP kinase, a protein kinase involved in apoptosis. DAPK2 mRNA is expressed abundantly in heart, lung and skeletal muscle. The mapping results indicated that DAPK2 is located in the central region of mouse chromosome 9. In vitro kinase assay revealed that DAPK2 is autophosphorylated and phosphorylates myosin light chain (MLC) as an exogenous substrate. DAPK2 binds directly to CaM and is activated in a Ca2+/CaM-dependent manner. A constitutively active DAPK2 mutant is generated by removal of the CaM-binding domain (deltaCaM). Treatment of agonists that elevate intracellular Ca2+-concentration led to the activation of DAPK2 and transfection studies revealed that DAPK2 is localized in the cytoplasm. Overexpression of DAPK2, but not the kinase negative mutant, significantly induced the morphological changes characteristic of apoptosis. These results indicate that DAPK2 is an additional member of DAP kinase family involved in apoptotic signaling.


Asunto(s)
Apoptosis/fisiología , Proteínas Quinasas Dependientes de Calcio-Calmodulina/fisiología , Células 3T3 , Animales , Proteínas Reguladoras de la Apoptosis , Células COS , Calcio/metabolismo , Proteínas Quinasas Dependientes de Calcio-Calmodulina/genética , Calmodulina/metabolismo , Mapeo Cromosómico , Proteínas Quinasas Asociadas a Muerte Celular , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Fosforilación , ARN Mensajero/metabolismo , Distribución Tisular , Transfección
9.
J Clin Oncol ; 11(8): 1602-8, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8336196

RESUMEN

PURPOSE: A phase I study was conducted to determine the maximum-tolerated dose (MTD) of a 14-day continuous infusion of etoposide, and to evaluate the pharmacokinetics in patients with lung cancer. PATIENTS AND METHODS: Etoposide was administered continuously through a central venous catheter using a pump. The starting dose level was 300 mg/m2 over 14 days, with dose escalations of 100 mg/m2 over 14 days until unacceptable toxicities occurred. Pharmacokinetic studies were performed in all patients. RESULTS: Twenty-one patients, 20 with non-small-cell lung cancer and one with refractory small-cell lung cancer, received 37 courses. No World Health Organization (WHO) grade III or greater toxicity occurred at doses up to 400 mg/m2 over 14 days. At 700 mg/m2 over 14 days, all four patients experienced grade III or IV leukocytopenia, and two developed grade III stomatitis. No cumulative toxicity was observed. A steady concentration of etoposide was achieved 24 hours after the start of chemotherapy, and it was significantly correlated with surviving fractions of leukocytes (r = -.64, P = .001) and platelets (r = -.68, P < .001). The leukocyte count at the termination of chemotherapy predicted the nadir count (r = .93, P < .001). CONCLUSION: Steady blood levels of etoposide were maintained for prolonged periods, during 14-day continuous infusions. Leukocytopenia and stomatitis were dose-limiting. Nadir counts and surviving fractions of leukocytes were predicted by the leukocyte count at the end of chemotherapy and the concentration of etoposide, respectively. The recommended dose for phase II trials is 600 mg/m2 over 14 days.


Asunto(s)
Etopósido/administración & dosificación , Etopósido/farmacocinética , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anciano , Cateterismo Venoso Central , Esquema de Medicación , Etopósido/efectos adversos , Etopósido/uso terapéutico , Femenino , Enfermedades Hematológicas/inducido químicamente , Humanos , Bombas de Infusión , Infusiones Intravenosas , Neoplasias Pulmonares/metabolismo , Masculino , Persona de Mediana Edad
10.
Oncogene ; 34(32): 4177-89, 2015 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-25347736

RESUMEN

Most human cancers show chromosomal instability (CIN), but the precise mechanisms remain uncertain. Annexin A2 is frequently overexpressed in human cancers, and its relationship to tumorigenesis is poorly understood. We found that annexin A2 is overexpressed in the nuclei of CIN cells compared with cells with microsatellite instability (MIN). Ectopic annexin A2 expression in MIN cells results in a high level of aneuploidy and induces lagging chromosomes; suppression of annexin A2 in CIN cells reduces such CIN signatures with apoptosis of highly aneuploid cells. Ectopic expression of annexin A2 in MIN cells reduces the expression of centromere proteins. Conversely, annexin A2-knockdown in CIN cells increases the expression of centromere proteins. Moreover, the endogenous expression levels of centromere proteins in CIN cells were greatly reduced compared with MIN cell lines. The reduced expression of centromere proteins likely occurred due to aberrant centromere localization of coilin, a major component of the Cajal bodies. These results suggest that nuclear accumulation of annexin A2 has a crucial role in CIN by disrupting centromere function.


Asunto(s)
Anexina A2/genética , Centrómero/genética , Inestabilidad Cromosómica , Proteínas Nucleares/genética , Aneuploidia , Anexina A2/metabolismo , Apoptosis/genética , Autoantígenos/genética , Autoantígenos/metabolismo , Western Blotting , Células CACO-2 , Línea Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/metabolismo , Centrómero/metabolismo , Proteína A Centromérica , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Electroforesis en Gel Bidimensional , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Células HT29 , Humanos , Inestabilidad de Microsatélites , Proteínas Nucleares/metabolismo , Proteoma/genética , Proteoma/metabolismo , Proteómica/métodos , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
BMJ Open ; 5(11): e009157, 2015 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-26560063

RESUMEN

OBJECTIVE: POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes) syndrome is a rare multisystem disease characterised by plasma cell dyscrasia and overproduction of vascular endothelial growth factor (VEGF). VEGF is assumed to be useful in monitoring disease activity, because VEGF levels usually decrease after treatment. However, there is no study to investigate whether the extent of decrease in VEGF correlates with clinical outcome. We tested the predictive efficacy of serum VEGF levels in POEMS syndrome. METHOD: This was an institutional review board approved retrospective observational cohort study of 20 patients with POEMS monitored regularly for more than 12 months (median follow-up, 87 months) after treatment onset using our prospectively accumulated database of POEMS from 1999 to 2015. Patients were treated by autologous peripheral blood stem cell transplantation or thalidomide administration. Serum VEGF was measured by ELISA. Outcome measures included clinical and laboratory findings and relapse-free survival. RESULTS: Serum VEGF levels decreased rapidly after treatment, and stabilised by 6 months post treatment. Patients with normalised serum VEGF levels (<1040 pg/mL) at 6 months showed prolonged relapse-free survival (HR=12.81, 95% CI 2.691 to 90.96; p=0.0001) and greater later clinical improvement. The rate of serum VEGF reduction over the first 6 months post treatment correlated with increased grip strength, serum albumin levels, and compound muscle action potential amplitudes at 12 months. CONCLUSIONS: Serum VEGF level at 6 months post treatment is a predicative biomarker for disease activity and prognosis in POEMS syndrome. Serum VEGF could be used as a surrogate endpoint for relapse-free survival or clinical or laboratory improvement of POEMS syndrome for clinical trials.


Asunto(s)
Síndrome POEMS/sangre , Síndrome POEMS/terapia , Trasplante de Células Madre de Sangre Periférica , Talidomida/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
12.
Environ Sci Pollut Res Int ; 22(5): 3947-54, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25300186

RESUMEN

The aim of the study was to use the comet assay (single-cell gel electrophoresis) and micronucleus test to assess the extent of genomic damage in the whole blood of Dendropsophus minutus from agroecosystems with great use of agrochemicals and to compare the results to those obtained from animals living in unpolluted areas. Our results indicated that specimens of D. minutus collected in perturbed areas exhibited higher amounts of DNA damage in blood cells in comparison to animals from areas free of agricultural activities. The average and standard deviation of all comet assay parameters (tail length, percentage of DNA in the tail, and olive tail moment) and micronuclei frequency were significantly higher in specimens collected in perturbed areas than in the animals from preserved areas. Our study showed that animals from perturbed areas, such as agroecosystems, tend to have higher amounts of DNA damage than animals from reference areas. Moreover, we can conclude that D. minutus tadpoles could be included as a model organism in biomonitoring studies.


Asunto(s)
Anuros/genética , Daño del ADN , Monitoreo del Ambiente , Contaminación Ambiental/efectos adversos , Xenobióticos/efectos adversos , Agricultura , Animales , Brasil , Ensayo Cometa , Monitoreo del Ambiente/métodos , Genómica , Pruebas de Micronúcleos
13.
J Cereb Blood Flow Metab ; 14(1): 156-65, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8263052

RESUMEN

Brain protection during open heart surgery in the neonate and infant remains inadequate. Effects of the excitatory neurotransmitter antagonists MK-801 and NBQX on recovery of brain cellular energy state and metabolic rates were evaluated in 34 4-week-old piglets (10 MK-801, 10 NBQX, 14 controls) undergoing cardiopulmonary bypass and hypothermic circulatory arrest at 15 degrees C nasopharyngeal temperature for 1 h, as is used clinically for repair of congenital heart defects. MK-801 (dizocilpine) (0.75 mg/kg) or NBQX [2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline] (25 mg/kg) was given intravenously before cardiopulmonary bypass. Equivalent doses were placed in the cardiopulmonary bypass prime plus continuous infusions after reperfusion (0.15 mg kg-1h-1 and 5 mg kg-1h-1). Changes in high-energy phosphate concentrations and pH were analyzed by magnetic resonance spectroscopy in 17 animals until 225 min after reperfusion. Cerebral blood flow determined by radioactive microspheres as well as cerebral oxygen and glucose consumption were studied in 17 other animals. Cerebral blood flow and oxygen consumption were depressed relative to control by both MK-801 and NBQX at baseline. Recovery of phosphocreatine (p = 0.010), ATP (p = 0.030), and intracellular pH (p = 0.004) was accelerated by MK-801 and retarded by NBQX over the 45 min of rewarming reperfusion and the first hour of normothermic reperfusion. The final recovery of ATP at 3 h and 45 min reperfusion was significantly reduced by NBQX (46 +/- 26% baseline, mean +/- SD) versus control (81 +/- 19%) and MK-801 (75 +/- 8%) (p = 0.030). Cerebral oxygen consumption recovered to 105 +/- 30% baseline in group MK-801 and 94 +/- 31% in control but only to 61 +/- 22% in group NBQX (p = 0.070). Cerebral blood flow stayed significantly lower in group NBQX relative to control. Thus, MK-801 accelerates recovery of cerebral high-energy phosphates and metabolic rate after cardiopulmonary bypass and hypothermic circulatory arrest in the immature animal. At the dosage used NBQX exerts an adverse effect.


Asunto(s)
Encéfalo/metabolismo , Maleato de Dizocilpina/farmacología , Paro Cardíaco Inducido , Quinoxalinas/farmacología , Animales , Circulación Cerebrovascular , Metabolismo Energético , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Membranas Intracelulares/metabolismo , Lactatos/metabolismo , Ácido Láctico , Oxígeno/metabolismo , Fosfatos/metabolismo , Porcinos , Porcinos Enanos
14.
Biochem Pharmacol ; 33(5): 807-14, 1984 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-6370262

RESUMEN

To assess the importance of non-ADH ethanol metabolism, ADH-negative and ADH-positive deermice were fed liquid diets containing ethanol or isocaloric carbohydrate for 2-4 weeks. Blood ethanol disappearance rate increased significantly after chronic ethanol feeding in both strains. Although at low ethanol concentrations (between 5 and 10 mM) there was no significant difference between ethanol-fed and pair-fed control animals, at high ethanol concentrations (between 40 and 70 mM) blood ethanol elimination rates were increased significantly after chronic ethanol feeding in both ADH-positive and ADH-negative animals. There was no significant effect of the catalase inhibitor 3-amino-1,2,4-triazole on the ethanol elimination/rates in both strains. Whereas catalase and ADH activities were not altered after chronic ethanol treatment, the activity of the microsomal ethanol-oxidizing system (MEOS) was enhanced three to four times in both strains, and microsomal cytochrome P-450 content was also increased significantly. When MEOS activity was expressed per cytochrome P-450 content, it was higher in ADH-negative than in ADH-positive animals, and it increased after ethanol administration. When microsomal proteins were separated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, ethanol-fed animals had a distinct band which reflected the increase in microsomal cytochrome P-450 content and seemed to reflect a unique form of cytochrome P-450 induced by ethanol. Thus, despite the absence of the ADH pathway, a large amount of ethanol was metabolized by MEOS in ADH-negative deermice; this was associated with increased blood ethanol elimination rates, enhanced MEOS activity, and quantitative and qualitative changes of cytochrome P-450.


Asunto(s)
Oxidorreductasas de Alcohol/metabolismo , Etanol/metabolismo , Peromyscus/metabolismo , Alcohol Deshidrogenasa , Animales , Catalasa/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Electroforesis en Gel de Poliacrilamida , Hígado/ultraestructura , Microscopía Electrónica , Microsomas Hepáticos/enzimología
15.
Eur J Endocrinol ; 138(4): 383-7, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9578504

RESUMEN

OBJECTIVE: To understand the molecular mechanisms by which catecholamine synthesis is controlled in pheochromocytomas--tumors that synthesize and release catecholamines, which are related to various clinical manifestations of the condition. METHODS: We measured the concentrations of mRNA coding for the catecholamine-synthesizing enzymes tyrosine hydroxylase, aromatic L-amino acid decarboxylase (AADC), dopamine beta-hydroxylase (DBH) and phenylethanolamine N-methyl transferase (PNMT) and for the catecholamine contents in 12 pheochromocytomas and 12 normal adrenal medullas. RESULTS: The mean content of total catecholamine and the beta-actin mRNA expression in the pheochromocytomas were almost the same as those in the normal adrenal medullas. However, the tyrosine hydroxylase, AADC and DBH mRNA concentrations in the pheochromocytomas were greater than those of the normal adrenal medullas. Conversely, the PNMT mRNA concentration in the pheochromocytomas was lower than that in the normal adrenal medullas. These differences are responsible for the difference in the proportions of catecholamines between pheochromocytomas and normal adrenal medullas. The constitutive expression of the catecholamine-synthesizing enzyme mRNAs varied in magnitude among the pheochromocytomas, and the tyrosine hydroxylase mRNA expressions correlated with the contents of total catecholamine in the tumors (r=0.964, P<0.0001). CONCLUSIONS: These findings indicate that catecholamine production in pheochromocytomas is primarily controlled by the level of gene expression.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Catecolaminas/biosíntesis , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación Neoplásica de la Expresión Génica/fisiología , Feocromocitoma/genética , ARN Mensajero/genética , Neoplasias de las Glándulas Suprarrenales/metabolismo , Médula Suprarrenal/metabolismo , Descarboxilasas de Aminoácido-L-Aromático/genética , Estudios de Casos y Controles , Dopamina beta-Hidroxilasa/genética , Código Genético , Humanos , Feniletanolamina N-Metiltransferasa/genética , Feocromocitoma/metabolismo , ARN Mensajero/biosíntesis , Tirosina 3-Monooxigenasa/genética
16.
Eur J Endocrinol ; 138(6): 707-12, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9678541

RESUMEN

The differential display of mRNA is a new strategy to identify genes that are differentially expressed under altered conditions. We applied this method to determine differential gene expression in the rat pheochromocytoma cell line during differentiation induced by nerve growth factor (NGF). Three different mRNA species were isolated, and their differential expression was confirmed by RT-PCR. One of the mRNA species was identified as stathmin, a 19 kDa cytosolic protein attracting increasing interest for its role in signal transduction. In the NGF-treated PC12 cells, the expression of stathmin mRNA increased in a time-dependent manner, as assessed by northern blot analysis and RT-PCR. We also assessed by northern blot analysis how the expression of stathmin mRNA was altered in human pheochromocytomas (n = 5) compared with that in normal adrenal medulla tissue (n = 5). The mRNA concentrations were found to be significantly greater in the pheochromocytomas than in the normal tissues. It has been shown that stathmin mRNA concentrations are increased in various tumor cells. As pheochromocytomas are well-differentiated tumors of neural origin, it is not unexpected that stathmin mRNA is overexpressed in these tumors. Stathmin was isolated and identified as a differentially expressed gene by the differential display method in PC12 cells during differentiation induced by NGF. In addition, stathmin mRNA was found to be overexpressed in human pheochromocytomas. The mechanisms responsible for the up-regulation of stathmin mRNA during differentiation of PC12 cells and the significance of its overexpression in human pheochromocytomas remain to be determined.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/metabolismo , Proteínas de Microtúbulos , Factores de Crecimiento Nervioso/farmacología , Feocromocitoma/metabolismo , Fosfoproteínas/genética , ARN Mensajero/metabolismo , Animales , Northern Blotting , Diferenciación Celular/fisiología , Humanos , Neuronas/citología , Células PC12 , Fosfoproteínas/análisis , Reacción en Cadena de la Polimerasa/métodos , Ratas , Estatmina , Transcripción Genética
17.
J Thorac Cardiovasc Surg ; 107(3): 822-8, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8127111

RESUMEN

Hypothermia is believed to improve the tolerance to both ischemia and cardiopulmonary bypass and is commonly used during heart operations, particularly in the neonate. However, hypothermia also causes calcium to accumulate in the myocyte experimentally, and an increase in intracellular calcium during ischemia may worsen the effect of ischemia and impair the postischemic recovery of function. This effect of hypothermia on intracellular calcium has generally not been considered in experiments that attempt to optimize the composition of cardioplegic solutions. We have evaluated the impact of hypothermia before cardioplegic ischemia on the efficacy of two common cardioplegic solutions, one with calcium (St. Thomas' Hospital cardioplegia) and the other without calcium (glucose-potassium cardioplegia), in 37 isolated blood-perfused neonatal lamb hearts. Left ventricular maximal developed pressure, positive maximum of the first derivative of left ventricular pressure, left ventricular stiffness constant at 10 mmHg end-diastolic pressure, coronary blood flow, and myocardial oxygen consumption were measured before and 30 minutes after 2 hours of cold ischemia. After baseline measurements were made, two groups of hearts (ST-C and GK-C) had perfusion-cooling for 10 minutes to 17 degrees C myocardial temperature, and two other groups (ST-NC and GK-NC) had the same period of normothermic perfusion. Then the hearts were arrested with 4 degrees C St. Thomas' cardioplegic in groups ST-C and ST-NC and with glucose-potassium cardioplegia in groups GK-C and GK-NC. In the groups without preischemic cooling, both St. Thomas' (group ST-NC) and glucose-potassium (group GK-NC) cardioplegia resulted in a similar recovery of function compared with baseline levels (group ST-NC: developed pressure = 91.3% +/- 9.2%, dP/dt = 88.1% +/- 8.9%, left ventricular stiffness constant = 96.1% +/- 3.3%; group GK-NC: developed pressure = 89.3% +/- 6.9%, dP/dt = 82.6% +/- 8.8%, left ventricular stiffness constant = 99.4% +/- 2.0%; data are mean plus or minus the standard deviation). However, with preischemic cooling, St. Thomas' cardioplegia (group ST-C) resulted in a significantly reduced recovery of both systolic and diastolic function (developed pressure = 81.6% +/- 6.2%, dP/dt = 75.1% +/- 8.4%, left ventricular stiffness constant = 103.7% +/- 2.7%) compared with that for both glucose-potassium cardioplegia (group GK-C: developed pressure = 92.4% +/- 8.7%, dP/dt = 83.7% +/- 6.0%, left ventricular stiffness constant = 100.5% +/- 2.1%) and St. Thomas' cardioplegia without preischemic cooling (group ST-NC) (p < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Calcio/metabolismo , Soluciones Cardiopléjicas/farmacología , Paro Cardíaco Inducido , Hemodinámica/efectos de los fármacos , Hipotermia Inducida , Daño por Reperfusión Miocárdica/prevención & control , Miocardio/metabolismo , Animales , Animales Recién Nacidos , Bicarbonatos/farmacología , Calcio/farmacología , Cloruro de Calcio/farmacología , Soluciones Cardiopléjicas/química , Glucosa/farmacología , Magnesio/farmacología , Daño por Reperfusión Miocárdica/etiología , Potasio/farmacología , Cloruro de Potasio/farmacología , Cloruro de Sodio/farmacología
18.
Chest ; 101(1): 288-9, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1309499

RESUMEN

Umbilical metastases have been almost exclusively reported in patients with adenocarcinomas of intra-abdominal organs. We present a case of small cell carcinoma of the lung with umbilical metastasis that was confirmed by biopsy. To our knowledge, this is the first reported case of umbilical metastasis from small cell lung cancer.


Asunto(s)
Carcinoma de Células Pequeñas/secundario , Neoplasias Pulmonares/patología , Ombligo , Anciano , Carcinoma de Células Pequeñas/patología , Humanos , Masculino , Ombligo/patología
19.
Chest ; 105(6): 1658-62, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8205857

RESUMEN

STUDY OBJECTIVE: We evaluated the interbronchoscopist variability in the diagnosis of lung cancer by flexible bronchoscopy. DESIGN AND SETTING: A retrospective review of the bronchoscopic records and clinical charts of patients at a university-affiliated hospital. PATIENTS AND MEASUREMENTS: All records of flexible bronchoscopic procedures performed for the diagnosis of lung cancer were retrospectively reviewed, and procedures that obtained histologic or cytologic evidence of malignancy were considered positive. Rates of positivity were compared according to the following factors: operator, operator experience, bronchoscopic findings, tumor location, and tumor laterality. Factors that affected the positivity rate were evaluated using logistic regression analysis. RESULTS: Of 384 bronchoscopic procedures performed in 353 patients, 275 (72 percent) were positive. The positivity rate differed significantly depending on the operator (p = 0.003) and the bronchoscopic findings (p < 0.001). A difference between operators was noted in technically difficult cases without epithelial or subepithelial findings and when tumors were located in the upper lobe or the superior segment of the lower lobe. The bronchoscopic findings and the operator also emerged as factors significantly affecting the positivity rate in the logistic analysis. CONCLUSIONS: The diagnostic yield of bronchoscopy for lung cancer is dependent on both the type of bronchial lesion present and the bronchoscopist.


Asunto(s)
Broncoscopía/estadística & datos numéricos , Neoplasias Pulmonares/epidemiología , Broncoscopía/métodos , Humanos , Modelos Logísticos , Neoplasias Pulmonares/diagnóstico , Variaciones Dependientes del Observador , Estudios Retrospectivos
20.
J Thorac Cardiovasc Surg ; 105(2): 207-12; discussion 212-3, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8429646

RESUMEN

Hypothermia has been reported to increase intracellular ionized calcium, which may aggravate injury resulting from ischemia and reperfusion. The effects of plasma ionized calcium concentration ([Ca2+]) during hypothermic perfusion on recovery after 2 hours of cold cardioplegic ischemia were evaluated in 32 isolated, blood-perfused neonatal lamb hearts. Three groups of hearts (B, C, and D) were perfusion-cooled for 10 minutes to a myocardial temperature of 17 degrees C and then arrested with St. Thomas' Hospital cardioplegic solution. Group A had 10 minutes of normothermic perfusion before cardioplegia. Group B had cooling with normal [Ca2+]. Group C had citrate added as cooling was started to lower [Ca2+] (0.26 mmol/L), and it was not normalized until 15 minutes into reperfusion. Group D received citrate plus Ca2+ to give normal [Ca2+] during cooling. Groups B and D showed a significantly reduced recovery (p < 0.05) in left ventricular systolic function (developed pressure and the rate of pressure rise) and diastolic function (stiffness constant) than groups A and C. During preischemic cooling, oxygen consumption per beat and coronary vascular resistance increased significantly in groups B and D, but both oxygen consumption and coronary vascular resistance were significantly lower in group C than in groups B and D so long as [Ca2+] was low. The data show that preischemic hypothermia results in reduced postischemic recovery of function compared with simultaneous induction of cardioplegia and hypothermia. Low [Ca2+] during preischemic hypothermia and early reperfusion offsets this deleterious effect of hypothermia.


Asunto(s)
Calcio/sangre , Paro Cardíaco Inducido/métodos , Hipotermia Inducida , Función Ventricular Izquierda/fisiología , Animales , Animales Recién Nacidos , Isquemia Miocárdica/fisiopatología , Consumo de Oxígeno/fisiología , Ovinos , Resistencia Vascular/fisiología
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