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1.
Mol Psychiatry ; 22(10): 1473-1482, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28138157

RESUMEN

Manic episodes are one of the major diagnostic symptoms in a spectrum of neuropsychiatric disorders that include schizophrenia, obsessive-compulsive disorder and bipolar disorder (BD). Despite a possible association between BD and the gene encoding phospholipase Cγ1 (PLCG1), its etiological basis remains unclear. Here, we report that mice lacking phospholipase Cγ1 (PLCγ1) in the forebrain (Plcg1f/f; CaMKII) exhibit hyperactivity, decreased anxiety-like behavior, reduced depressive-related behavior, hyperhedonia, hyperphagia, impaired learning and memory and exaggerated startle responses. Inhibitory transmission in hippocampal pyramidal neurons and striatal dopamine receptor D1-expressing neurons of Plcg1-deficient mice was significantly reduced. The decrease in inhibitory transmission is likely due to a reduced number of γ-aminobutyric acid (GABA)-ergic boutons, which may result from impaired localization and/or stabilization of postsynaptic CaMKII (Ca2+/calmodulin-dependent protein kinase II) at inhibitory synapses. Moreover, mutant mice display impaired brain-derived neurotrophic factor-tropomyosin receptor kinase B-dependent synaptic plasticity in the hippocampus, which could account for deficits of spatial memory. Lithium and valproate, the drugs presently used to treat mania associated with BD, rescued the hyperactive phenotypes of Plcg1f/f; CaMKII mice. These findings provide evidence that PLCγ1 is critical for synaptic function and plasticity and that the loss of PLCγ1 from the forebrain results in manic-like behavior.


Asunto(s)
Trastorno Bipolar/enzimología , Trastorno Bipolar/genética , Fosfolipasa C gamma/metabolismo , Prosencéfalo/enzimología , Animales , Trastorno Bipolar/parasitología , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Hipocampo/enzimología , Hipocampo/metabolismo , Ratones , Plasticidad Neuronal/fisiología , Neuronas/enzimología , Neuronas/metabolismo , Fosfolipasa C gamma/deficiencia , Fosfolipasa C gamma/genética , Prosencéfalo/patología , Células Piramidales/metabolismo , Receptor trkB/metabolismo , Receptores de Dopamina D1 , Sinapsis/enzimología , Sinapsis/patología , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/metabolismo
3.
Water Sci Technol ; 73(10): 2453-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27191567

RESUMEN

In this study, several natural materials were investigated in order to clarify their potential use as cesium (Cs) adsorbents in situ. Four materials--carbonized rice hull, beech sawdust, oak sawdust, and charcoal (Japanese cedar)--which were previously shown to have Cs adsorption capabilities, were examined. Cs adsorption experiments were conducted using different initial Cs and adsorbent concentrations. The physical properties, adsorption isotherms, and adsorption processes were then examined, so as to exploit the Cs adsorption characteristics in the field. Based on these findings, carbonized rice hull and beech sawdust were selected as effective Cs adsorbents. It was found that these materials show continuous and stable Cs adsorption rates for different initial Cs concentrations. The adsorption efficiency of these two adsorption materials in combination was considered, and it was shown that the adsorption isotherms for carbonized rice hull and beech sawdust follow the Freundlich model. Furthermore, the beech sawdust adsorption process exhibited better agreement with the calculated values obtained via the adsorption rate model and the adsorption kinetics model than did the carbonized rice hull adsorption.


Asunto(s)
Cesio/química , Carbón Orgánico , Contaminantes Químicos del Agua/química , Madera , Adsorción , Carbono , Concentración de Iones de Hidrógeno , Cinética , Soluciones , Eliminación de Residuos Líquidos/métodos
4.
Br J Cancer ; 110(4): 1027-33, 2014 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-24357795

RESUMEN

BACKGROUND: The endothelin axis has been shown to have a pivotal role in several human malignancies. The aim of this study was to clarify the clinical importance of endothelin receptor type B (ETBR) in human oesophageal squamous cell carcinoma (OSCC). METHODS: We evaluated ETBR expression in 107 patients with OSCC by immunohistochemistry. Microvessel density (MVD) and lymphatic vessel density were assessed by CD31 and D2-40 immunostaining, respectively. Furthermore, CD4, CD8, and CD45RO+ tumour-infiltrating lymphocytes (TILs) were immunohistochemically analysed. RESULTS: Sixty-one (57%) cases showed high expression of ETBR. Endothelin receptor type B expression was correlated with several clinicopathological factors including tumour differentiation, tumour depth, and lymph node metastasis. The overall and disease-specific survival rates were significantly lower in patients with high ETBR expression than patients with low expression. Furthermore, multivariate analysis revealed that ETBR status was an independent prognostic factor for patient survival. Mechanistic analysis indicated that MVD was significantly higher in tumour tissues with high ETBR expression compared with those with low expression, suggesting that angiogenesis may be a key mechanism in tumour progression and metastasis of OSCC mediated by ETBR expression. By contrast, there were no significant correlations between TILs and ETBR expression. CONCLUSION: Endothelin receptor type B has a pivotal role in oesophageal cancer and may be therapeutic target for this intractable malignancy.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Linfocitos Infiltrantes de Tumor/patología , Neovascularización Patológica/patología , Receptor de Endotelina B/metabolismo , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidad , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidad , Carcinoma de Células Escamosas de Esófago , Femenino , Humanos , Antígenos Comunes de Leucocito/metabolismo , Linfangiogénesis , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Pronóstico , Receptor de Endotelina B/biosíntesis , Sobrevida
5.
Anaesthesia ; 69(7): 693-700, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24773263

RESUMEN

Cardiac surgery with cardiopulmonary bypass is associated with the development of a systemic inflammatory response that can often lead to dysfunction of major organs. We hypothesised that the highly selective α2-adrenergic agonist, dexmedetomidine, attenuates the systemic inflammatory response. Forty-two patients were randomly assigned to receive dexmedetomidine or saline after aortic cross-clamping). The mean (SD) levels of the nuclear protein plasma high-mobility group box 1 increased significantly from 5.1 (2.2) ng ml(-1) during (16.6 (7.3) ng ml(-1) ) and after (14.3 (8.2) ng ml(-1) ) cardiopulmonary bypass in the saline group. In the dexmedetomidine group, the levels increased significantly only during cardiopulmonary bypass (4.0 (1.9) ng ml(-1) baseline vs. 10.8 (2.7) ng ml(-1) ) but not after (7.4 (3.8) ng ml(-1) ). Dexmedetomidine infusion also suppressed the rise in mean (SD) interleukin-6 levels after cardiopulmonary bypass (a rise of 124.5 (72.0) pg ml(-1) vs. 65.3 (30.9) pg ml(-1)). These suppressive effects of dexmedetomidine might be due to the inhibition of nuclear factor kappa B activation and suggest that intra-operative dexmedetomidine may beneficially inhibit inflammatory responses associated with ischaemia-reperfusion injury during cardiopulmonary bypass.


Asunto(s)
Analgésicos no Narcóticos/farmacología , Puente Cardiopulmonar/efectos adversos , Dexmedetomidina/farmacología , Mediadores de Inflamación/sangre , Cuidados Posoperatorios/métodos , Síndrome de Respuesta Inflamatoria Sistémica/sangre , Síndrome de Respuesta Inflamatoria Sistémica/prevención & control , Anciano , Analgésicos no Narcóticos/sangre , Biomarcadores/sangre , Dexmedetomidina/sangre , Femenino , Humanos , Interleucina-6/sangre , Masculino , FN-kappa B/sangre , FN-kappa B/efectos de los fármacos , Estudios Prospectivos , Cloruro de Sodio/administración & dosificación , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Factores de Tiempo , Resultado del Tratamiento
6.
R Soc Open Sci ; 11(1): 231893, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38204785

RESUMEN

[This corrects the article DOI: 10.1098/rsos.180139.][This corrects the article DOI: 10.1098/rsos.180139.].

8.
Scand J Med Sci Sports ; 23(5): e286-92, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23647307

RESUMEN

We examined whether post-exercise macronutrient supplementation during a 5-month home-based interval walking training (IWT) accelerated exercise-induced increases in skeletal muscle mass and strength in healthy middle-aged and older women. Thirty-five women (41-78 years) were randomly divided into two groups: IWT alone (CNT, n = 18) or IWT plus post-exercise macronutrient (7.6 g protein, 32.5 g carbohydrate, and 4.4 g fat) supplementation (NUT, n = 17). For IWT, all subjects were instructed to repeat five or more sets of 3-min low-intensity walking at 40% peak aerobic capacity (Vo2 peak ), followed by a 3-min high-intensity walking above 70% Vo2 peak per day for 4 or more days per week. We determined Vo2 peak , thigh muscle tissue area by computer tomography, and thigh muscle strength in all subjects before and after IWT. We found that an increase in hamstring muscle tissue area was 2.8 ± 1.2% in NUT vs -1.0 ± 0.7% in CNT and that in isometric knee flexion force was 16.3 ± 3.7% in NUT vs 6.5 ± 3.0% in CNT; both were significantly higher in NUT than in CNT (both, P < 0.001). Thus, post-exercise macronutrient supplementation enhanced the increases in thigh muscle mass and strength, although partially, in home-based IWT in middle-aged and older women.


Asunto(s)
Articulación de la Rodilla/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/crecimiento & desarrollo , Caminata/fisiología , Adulto , Anciano , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Femenino , Humanos , Japón , Persona de Mediana Edad , Músculo Esquelético/anatomía & histología , Músculo Esquelético/fisiología , Consumo de Oxígeno , Muslo/fisiología
9.
Eur J Gynaecol Oncol ; 34(4): 332-5, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24020141

RESUMEN

Embryonal rhabdomyosarcoma (RMS) is a rare sarcoma that characteristically occurs in children. The current treatment protocols are based on trials performed in patients under 21 years of age. Embryonal RMS in women over 20 years of age is rare, and studies on treatments and outcomes are limited. The authors here in report a case of a 35-year-old woman with ectocervical RMS who was treated with radical hysterectomy followed by chemotherapy. She is currently disease-free. Based on a literature review, the authors recommend a surgical approach in combination with chemotherapy for treatment of embryonal RMS in adult patients.


Asunto(s)
Rabdomiosarcoma Embrionario/terapia , Neoplasias Uterinas/terapia , Adulto , Terapia Combinada , Femenino , Humanos , Rabdomiosarcoma Embrionario/patología , Neoplasias Uterinas/patología
11.
Nat Cell Biol ; 3(2): 210-4, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11175755

RESUMEN

The origin of eukaryotic cell nuclei by symbiosis of Archaea in Bacteria was proposed on the basis of the phylogenetic topologies of genes. However, it was not possible to conclude whether or not the genes involved were authentic representative genes. Furthermore, using the BLAST and FASTA programs, the similarity of open reading frame (ORF) groups between three domains (Eukarya, Archaea and Bacteria) was estimated at one threshold. Therefore, their similarities at other thresholds could not be clarified. Here we use our newly developed 'homology-hit analysis' method, which uses multiple thresholds, to determine the origin of the nucleus. We removed mitochondria-related ORFs from yeast ORFs, and determined the number of yeast orthologous ORFs in each functional category to the ORFs in six Archaea and nine Bacteria at several thresholds (E-values) using the BLAST. Our results indicate that yeast ORFs related to the nucleus may share their origins with archaeal ORFs, whereas ORFs that are related to the cytoplasm may share their origins with bacterial ORFs. Our results thus strongly support the idea of nucleus symbiosis.


Asunto(s)
Archaea/genética , Bacterias/genética , Núcleo Celular/genética , Evolución Molecular , Sistemas de Lectura Abierta/genética , Simbiosis , Levaduras/genética , Archaea/fisiología , Fenómenos Fisiológicos Bacterianos , Núcleo Celular/fisiología , ADN/genética , Bases de Datos Factuales , Modelos Biológicos , Homología de Secuencia , Levaduras/fisiología
13.
J Exp Med ; 169(4): 1309-21, 1989 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-2926327

RESUMEN

Expression of MHC class I genes varies according to developmental stage and type of tissues. To study the basis of class I gene regulation in tissues in vivo, we examined binding of nuclear proteins to the conserved cis sequence of the murine H-2 gene, class I regulatory element (CRE), which contains two independent factor-binding sites, region I and region II. In gel mobility shift analyses we found that extracts from adult tissues that express class I genes, such as spleen and liver, had binding activity to region I. In contrast, extracts from brain, which does not express class I genes, did not show region I binding activity. In addition, fetal tissues that express class I gene at very low levels, also did not reveal region I binding activity. Binding activity to region I became detectable during the neonatal period when class I gene expression sharply increases. Most of these tissues showed binding activity to region II, irrespective of class I gene expression. Although region II contained a sequence similar to the AP-1 recognition site, AP-1 was not responsible for the region II binding activity detected in this work. These results illustrate a correlation between region I binding activity and developmental and tissue-specific expression of MHC class I genes. The CRE exerts an enhancer-like activity in cultured fibroblasts. We evaluated the significance of each factor binding to CRE. Single 2-bp mutations were introduced into the CRE by site-directed mutagenesis and the ability of each mutant to elicit the enhancer activity was tested in transient CAT assays. A mutation that eliminated region I protein binding greatly impaired enhancer activity. A mutation that eliminated region II binding also caused a lesser but measurable effect. We conclude that region I and region II are both capable of enhancing transcription of the class I gene. These results indicate that in vivo regulation of MHC class I gene expression is mediated by binding of trans-acting factors to the CRE.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Regulación de la Expresión Génica , Antígenos H-2/genética , Proteínas Nucleares/fisiología , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/fisiología , Animales , Análisis Mutacional de ADN , Elementos de Facilitación Genéticos , Ratones , Distribución Tisular , Transcripción Genética
14.
J Exp Med ; 189(10): 1621-30, 1999 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-10330441

RESUMEN

Asthma is a chronic disease characterized by increased airway responsiveness and airway inflammation. The functional role of nitric oxide (NO) and the various nitric oxide synthase (NOS) isoforms in human asthma is controversial. To investigate the role of NO in an established model of allergic asthma, mice with targeted deletions of the three known isoforms of NOS (NOS1, 2, and 3) were studied. Although the inducible (NOS2) isoform was significantly upregulated in the lungs of ovalbumin (OVA)-sensitized and -challenged (OVA/OVA) wild-type (WT) mice and was undetectable in similarly treated NOS2-deficient mice, airway responsiveness was not significantly different between these groups. OVA/OVA endothelial (NOS3)-deficient mice were significantly more responsive to methacholine challenge compared with similarly treated NOS1 and NOS1&3-deficient mice. Airway responsiveness in OVA/OVA neuronal (NOS1)-deficient and neuronal/endothelial (NOS1&3) double-deficient mice was significantly less than that observed in similarly treated NOS2 and WT groups. These findings demonstrate an important function for the nNOS isoform in controlling the inducibility of airway hyperresponsiveness in this model of allergic asthma.


Asunto(s)
Asma/inmunología , Óxido Nítrico Sintasa/deficiencia , Neumonía/inmunología , Animales , Asma/enzimología , Asma/etiología , Líquido del Lavado Bronquioalveolar/citología , Calcio/metabolismo , Modelos Animales de Enfermedad , Marcación de Gen/métodos , Histocitoquímica , Humanos , Isoenzimas/deficiencia , Pulmón/enzimología , Cloruro de Metacolina , Ratones , Ratones Noqueados , Ovalbúmina , Pletismografía
15.
Clin Exp Dermatol ; 35(3): 263-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19538187

RESUMEN

Slow-growing sarcomas may give rise to intractable wounds, which may be attributed to commoner causes. A 57-year-old man with diabetes mellitus presented with a 24-year history of a chronic wound that originated on his left great toe. Because of the long history, the nonspecific histological findings and the complication of ulcerative colitis, we misdiagnosed his ulcer as pyoderma gangrenosum. The wound was eventually diagnosed correctly by histological examination of a skin biopsy and the use of immunohistochemistry to detect cytokeratin, epithelial membrane antigen and vimentin. Specimens obtained 16 years earlier showed the same staining pattern. Radiological examinations revealed no metastasis. The patient received a below-knee amputation without further chemotherapy or radiotherapy. When patients have intractable ulcers, appropriate biopsies and immunohistochemical examinations are sometimes necessary to exclude a malignancy even if the history and symptoms do not suggest a diagnosis of sarcoma.


Asunto(s)
Pie , Sarcoma/patología , Neoplasias Cutáneas/patología , Diagnóstico Diferencial , Traumatismos de los Pies/patología , Humanos , Masculino , Persona de Mediana Edad , Sarcoma/cirugía , Neoplasias Cutáneas/cirugía , Factores de Tiempo , Resultado del Tratamiento
16.
Ann Biomed Eng ; 48(12): 2705-2706, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33140243

RESUMEN

A unique feature of COVID-19 interstitial pneumonia is an abrupt progression to respiratory failure. Our calculation shows that this abrupt deteriorate may be caused by a sudden shift in the spread of virus-laden bioaerosols through the airways to many different regions of the lungs from the initial site of infection.


Asunto(s)
COVID-19 , Pulmón , Modelos Biológicos , SARS-CoV-2/metabolismo , Virión/metabolismo , COVID-19/metabolismo , COVID-19/patología , COVID-19/transmisión , Humanos , Pulmón/metabolismo , Pulmón/patología
17.
J Sports Med Phys Fitness ; 49(4): 424-31, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20087302

RESUMEN

AIM: The aim of this paper was to assess the effects of branched-chain amino acid (BCAA) supplementation on muscle soreness, muscle damage and inflammation during an intensive training program. METHODS: Twelve long-distance runners (20 + or - 1 year-old) participated in a double-blinded crossover designed study conducted during two intensive training periods (three-day). The subjects were provided either a drink containing BCAA (0.8% BCAA in a 3.5% carbohydrate solution; 2,500 mL/day) or an isocaloric placebo drink during each training period. All subjects completed the same training program (total running distance: males: 86 km, females: 64 km), and ate the same meals during the training period. Whole body muscle soreness and fatigue sensation were measured in the morning before and during the training period by Visual Analogue Scale method. Plasma creatine kinase (CK), lactate dehydrogenase (LDH), and granulocyte elastase (GEL) levels were measured as indicators of muscle damage and inflammation before and after the training period. RESULTS: Muscle soreness and fatigue sensation during the training period in the BCAA trial were lower than those in the placebo trial (-32% and -24%, respectively; P<0.05). The plasma CK, LDH, and GEL levels after the training program in the BCAA trial were lower than those in the placebo trial (-21%, -6%, and -15%, respectively; P<0.05). CONCLUSIONS: These results demonstrate that BCAA supplementation during an intensive training program effectively reduces the muscle soreness and fatigue sensation, and that the perceived changes could be attributed to the attenuation of muscle damage and inflammation.


Asunto(s)
Aminoácidos de Cadena Ramificada/uso terapéutico , Suplementos Dietéticos , Tolerancia al Ejercicio/efectos de los fármacos , Inflamación/prevención & control , Músculo Esquelético/efectos de los fármacos , Dolor/tratamiento farmacológico , Adaptación Fisiológica/efectos de los fármacos , Creatina Quinasa/sangre , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , L-Lactato Deshidrogenasa/sangre , Elastasa de Leucocito/sangre , Modelos Lineales , Masculino , Contracción Muscular , Fatiga Muscular , Músculo Esquelético/lesiones , Evaluación Nutricional , Dolor/etiología , Dimensión del Dolor , Aptitud Física , Estadística como Asunto , Adulto Joven
18.
Eur Respir J ; 31(4): 783-9, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18094012

RESUMEN

Asthma is associated with increased numbers of T-cells in the lung. CC chemokine receptor (CCR)5 and CXC chemokine receptor (CXCR)3 have been reported to play important roles in the lung T-cell homing pathway, and may be potential targets for asthma therapy. The aim of the present study was to investigate the role of CCR5 and CXCR3 in allergen-induced acute asthma and to determine whether a novel small-molecule compound, TAK-779, targeting CCR5 and CXCR3 can attenuate allergic airway responses. Mice were sensitised with ovalbumin (OVA). mRNA expression of chemokine receptors in the lung were measured after the challenge with either aerosolised phosphate-buffered saline or OVA. OVA-sensitised mice were also treated with TAK-779. Respiratory function was measured, bronchoalveolar lavage was performed, and blood and lung samples were obtained. OVA challenge increased CCR3, CCR5 and CXCR3 expression in the lung. Treatment with TAK-779 significantly attenuated altered respiratory function and pulmonary allergic inflammation. The beneficial effect was associated with reduced expression of CCR5 and CXCR3 in the lung. These data demonstrate that blockade of CC chemokine receptor 5 and CXC chemokine receptor 3 using TAK-779, a synthetic nonpeptide compound, can prevent the development of asthma features in a mouse model. Thus, CC chemokine receptor 5 and CXC chemokine receptor 3 may be potential targets for asthma therapy.


Asunto(s)
Amidas/farmacología , Antiasmáticos/farmacología , Asma/tratamiento farmacológico , Asma/inmunología , Compuestos de Amonio Cuaternario/farmacología , Receptores CCR5 , Receptores CXCR3 , Animales , Modelos Animales de Enfermedad , Femenino , Inmunización , Ratones , Ratones Endogámicos BALB C , Ovalbúmina , Receptores CCR/antagonistas & inhibidores , Receptores CCR3/inmunología , Receptores CCR5/efectos de los fármacos , Receptores CCR5/inmunología , Receptores CXCR3/efectos de los fármacos , Receptores CXCR3/inmunología
19.
R Soc Open Sci ; 5(6): 180139, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30110423

RESUMEN

A specific periodic bar-and-joint framework with limited degrees of freedom is shown to have a transition mechanism when subjected to an external force. The static nonlinear elasticity of this framework under a uniaxial load is modelled with the two angular variables specifying the rotation and distortion of the linked square components. Numerically exploring the equilibrium paths then reveals a transition state of the structure at a critical value of the internal stiffness. A simplified formulation of the model with weak nonlinear terms yields an exact solution of its transition state. Load-displacement behaviour and stability for the two systems with or without approximation are analysed and compared.

20.
Mol Cell Biol ; 9(10): 4345-56, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2555690

RESUMEN

Low-molecular-weight RNA exhibiting transforming potential was identified in chemically induced lymphoma cells by the transformation of mink lung cells after transfection. The RNA was sequenced by the direct chemical method and was shown to be a small nuclear RNA, U5. The transforming potential of the RNA was further studied in quantitative transformation assays using 3Y1, a rat fibroblastic cell line. Transformed foci appeared with a latency of 3 to 4 weeks after transfection. U5-transformed 3Y1 cells frequently carried an amplified c-myc oncogene. In addition, U5 induced chromosome aberrations in transfected cells, indicating that the RNA acts as a clastogen. Transforming and clastogenic potentials were specifically inactivated when U5 was incubated with RNase H in the presence of a complementary oligonucleotide. We discuss a possible mechanism of U5-induced cell transformation.


Asunto(s)
Transformación Celular Neoplásica/genética , ARN Nuclear Pequeño/fisiología , Animales , Secuencia de Bases , Línea Celular , Supervivencia Celular , Aberraciones Cromosómicas , Endorribonucleasas , Técnicas In Vitro , Cinética , Datos de Secuencia Molecular , Mutágenos , ARN Nuclear Pequeño/metabolismo , ARN Nuclear Pequeño/toxicidad , Ratas , Ratas Endogámicas F344 , Ribonucleasa H , Homología de Secuencia de Ácido Nucleico , Transcripción Genética , Transfección
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