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1.
Mol Psychiatry ; 22(10): 1473-1482, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28138157

RESUMO

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.


Assuntos
Transtorno Bipolar/enzimologia , Transtorno Bipolar/genética , Fosfolipase C gama/metabolismo , Prosencéfalo/enzimologia , Animais , Transtorno Bipolar/parasitologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Hipocampo/enzimologia , Hipocampo/metabolismo , Camundongos , Plasticidade Neuronal/fisiologia , Neurônios/enzimologia , Neurônios/metabolismo , Fosfolipase C gama/deficiência , Fosfolipase C gama/genética , Prosencéfalo/patologia , Células Piramidais/metabolismo , Receptor trkB/metabolismo , Receptores de Dopamina D1 , Sinapses/enzimologia , Sinapses/patologia , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/metabolismo
3.
Water Sci Technol ; 73(10): 2453-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27191567

RESUMO

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.


Assuntos
Césio/química , Carvão Vegetal , Poluentes Químicos da Água/química , Madeira , Adsorção , Carbono , Concentração de Íons de Hidrogênio , Cinética , Soluções , Eliminação de Resíduos Líquidos/métodos
4.
Br J Cancer ; 110(4): 1027-33, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24357795

RESUMO

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.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Linfócitos do Interstício Tumoral/patologia , Neovascularização Patológica/patologia , Receptor de Endotelina B/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Antígenos Comuns de Leucócito/metabolismo , Linfangiogênese , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptor de Endotelina B/biossíntese , Sobrevida
5.
Anaesthesia ; 69(7): 693-700, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24773263

RESUMO

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.


Assuntos
Analgésicos não Narcóticos/farmacologia , Ponte Cardiopulmonar/efeitos adversos , Dexmedetomidina/farmacologia , Mediadores da Inflamação/sangue , Cuidados Pós-Operatórios/métodos , Síndrome de Resposta Inflamatória Sistêmica/sangue , Síndrome de Resposta Inflamatória Sistêmica/prevenção & controle , Idoso , Analgésicos não Narcóticos/sangue , Biomarcadores/sangue , Dexmedetomidina/sangue , Feminino , Humanos , Interleucina-6/sangue , Masculino , NF-kappa B/sangue , NF-kappa B/efeitos dos fármacos , Estudos Prospectivos , Cloreto de Sódio/administração & dosagem , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Fatores de Tempo , Resultado do Tratamento
6.
R Soc Open Sci ; 11(1): 231893, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38204785

RESUMO

[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.
Artigo em Inglês | MEDLINE | ID: mdl-23647307

RESUMO

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.


Assuntos
Articulação do Joelho/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/crescimento & desenvolvimento , Caminhada/fisiologia , Adulto , Idoso , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Feminino , Humanos , Japão , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio , Coxa da Perna/fisiologia
9.
Eur J Gynaecol Oncol ; 34(4): 332-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24020141

RESUMO

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.


Assuntos
Rabdomiossarcoma Embrionário/terapia , Neoplasias Uterinas/terapia , Adulto , Terapia Combinada , Feminino , Humanos , Rabdomiossarcoma Embrionário/patologia , Neoplasias Uterinas/patologia
11.
Nat Cell Biol ; 3(2): 210-4, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11175755

RESUMO

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.


Assuntos
Archaea/genética , Bactérias/genética , Núcleo Celular/genética , Evolução Molecular , Fases de Leitura Aberta/genética , Simbiose , Leveduras/genética , Archaea/fisiologia , Fenômenos Fisiológicos Bacterianos , Núcleo Celular/fisiologia , DNA/genética , Bases de Dados Factuais , Modelos Biológicos , Homologia de Sequência , Leveduras/fisiologia
13.
J Exp Med ; 169(4): 1309-21, 1989 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2926327

RESUMO

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.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Antígenos H-2/genética , Proteínas Nucleares/fisiologia , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/fisiologia , Animais , Análise Mutacional de DNA , Elementos Facilitadores Genéticos , Camundongos , Distribuição Tecidual , Transcrição Gênica
14.
J Exp Med ; 189(10): 1621-30, 1999 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-10330441

RESUMO

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.


Assuntos
Asma/imunologia , Óxido Nítrico Sintase/deficiência , Pneumonia/imunologia , Animais , Asma/enzimologia , Asma/etiologia , Líquido da Lavagem Broncoalveolar/citologia , Cálcio/metabolismo , Modelos Animais de Doenças , Marcação de Genes/métodos , Histocitoquímica , Humanos , Isoenzimas/deficiência , Pulmão/enzimologia , Cloreto de Metacolina , Camundongos , Camundongos Knockout , Ovalbumina , Pletismografia
15.
Clin Exp Dermatol ; 35(3): 263-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19538187

RESUMO

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.


Assuntos
, Sarcoma/patologia , Neoplasias Cutâneas/patologia , Diagnóstico Diferencial , Traumatismos do Pé/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Sarcoma/cirurgia , Neoplasias Cutâneas/cirurgia , Fatores de Tempo , Resultado do Tratamento
16.
Ann Biomed Eng ; 48(12): 2705-2706, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33140243

RESUMO

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.


Assuntos
COVID-19 , Pulmão , Modelos Biológicos , SARS-CoV-2/metabolismo , Vírion/metabolismo , COVID-19/metabolismo , COVID-19/patologia , COVID-19/transmissão , Humanos , Pulmão/metabolismo , Pulmão/patologia
17.
J Sports Med Phys Fitness ; 49(4): 424-31, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20087302

RESUMO

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.


Assuntos
Aminoácidos de Cadeia Ramificada/uso terapêutico , Suplementos Nutricionais , Tolerância ao Exercício/efeitos dos fármacos , Inflamação/prevenção & controle , Músculo Esquelético/efeitos dos fármacos , Dor/tratamento farmacológico , Adaptação Fisiológica/efeitos dos fármacos , Creatina Quinase/sangue , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , L-Lactato Desidrogenase/sangue , Elastase de Leucócito/sangue , Modelos Lineares , Masculino , Contração Muscular , Fadiga Muscular , Músculo Esquelético/lesões , Avaliação Nutricional , Dor/etiologia , Medição da Dor , Aptidão Física , Estatística como Assunto , Adulto Jovem
18.
Eur Respir J ; 31(4): 783-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18094012

RESUMO

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.


Assuntos
Amidas/farmacologia , Antiasmáticos/farmacologia , Asma/tratamento farmacológico , Asma/imunologia , Compostos de Amônio Quaternário/farmacologia , Receptores CCR5 , Receptores CXCR3 , Animais , Modelos Animais de Doenças , Feminino , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Receptores CCR/antagonistas & inibidores , Receptores CCR3/imunologia , Receptores CCR5/efeitos dos fármacos , Receptores CCR5/imunologia , Receptores CXCR3/efeitos dos fármacos , Receptores CXCR3/imunologia
19.
R Soc Open Sci ; 5(6): 180139, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30110423

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-2555690

RESUMO

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.


Assuntos
Transformação Celular Neoplásica/genética , RNA Nuclear Pequeno/fisiologia , Animais , Sequência de Bases , Linhagem Celular , Sobrevivência Celular , Aberrações Cromossômicas , Endorribonucleases , Técnicas In Vitro , Cinética , Dados de Sequência Molecular , Mutagênicos , RNA Nuclear Pequeno/metabolismo , RNA Nuclear Pequeno/toxicidade , Ratos , Ratos Endogâmicos F344 , Ribonuclease H , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica , Transfecção
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