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1.
Pharmazie ; 79(1): 2-5, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38509631

RESUMO

Nanoparticles are used in a variety of fields; for example, titanium oxide nanoparticles are used in paints, food additives, cosmetics, and sunscreen materials. Although the use of titanium oxide nanoparticles is regulated, their safety has not been established. Furthermore, the interaction between titanium oxide nanoparticles and various chemical substances and pharmaceuticals is unknown. We co-administered rutile-type titanium oxide nanoparticles (nTR) or anatase-type titanium oxide nanoparticles (nTA) to mice together with paraquat (PQ), cisplatin (CDDP), or anti-5-aminosalicylic acid (5-ASA), and investigated the extent, if any, of liver and kidney injury. As a result, when nTA and nTR were administered alone, no increases were observed in aspartate aminotransferase (AST) and alanine aminotransferase (ALT), which are indicators of liver damage, or urea nitrogen (BUN), which is an indicator of kidney damage. Next, nTA and nTR were co-administered with PQ, CDDP or 5-ASA. Although no increase in ALT or AST was observed, BUN levels increased significantly and acute kidney injury was induced. The findings suggested that titanium oxide nanoparticles induce acute kidney injury through their interaction with chemicals and drugs.


Assuntos
Injúria Renal Aguda , Nanopartículas , Titânio , Camundongos , Animais , Cisplatino/toxicidade , Paraquat , Mesalamina , Nanopartículas/química , Injúria Renal Aguda/induzido quimicamente
2.
Neuropathol Appl Neurobiol ; 42(3): 279-90, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26111727

RESUMO

AIMS: Primary central nervous system lymphoma (PCNSL) manifest aggressive clinical behaviour and have poor prognosis. Although constitutive activation of the nuclear factor-κB (NF-κB) pathway has been documented, knowledge about the genetic alterations leading to the impairment of the NF-κB pathway in PCNSLs is still limited. This study was aimed to unravel the underlying genetic profiles of PCNSL. METHODS: We conducted the systematic sequencing of 21 genes relevant to the NF-κB signalling network for 71 PCNSLs as well as the pyrosequencing of CD79B and MYD88 mutation hotspots in a further 35 PCNSLs and 46 glioblastomas (GBMs) for validation. RESULTS: The results showed that 68 out of 71 PCNSLs had mutations in the NF-κB gene network, most commonly affecting CD79B (83%), MYD88 (76%), TBL1XR1 (23%), PRDM1 (20%) and CREBBP1 (20%). These mutations, particularly CD79B and MYD88, frequently coincided within each tumour in various combinations, simultaneously affecting diverse pathways within the network. No GBMs had hotspot mutation of CD79B Y196 and MYD88 L265. CONCLUSIONS: The prevalence of CD79B and MYD88 mutations in PCNSLs was considerably higher than reported in systemic diffuse large B-cell lymphomas. This observation could reflect the paucity of antigen stimuli from the immune system in the central nervous system (CNS) and the necessity to substitute them by the constitutive activation of CD79B and MYD88 that would initiate the signalling cascades. These hotspot mutations may serve as a genetic hallmark for PCNSL serving as a genetic marker for diagnose and potential targets for molecular therapy.


Assuntos
Antígenos CD79/genética , Neoplasias do Sistema Nervoso Central/genética , Linfoma Difuso de Grandes Células B/genética , Fator 88 de Diferenciação Mieloide/genética , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase
3.
Heredity (Edinb) ; 116(1): 75-83, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26264548

RESUMO

A significant feature of the genomes of Lepidoptera, butterflies and moths, is the high conservation of chromosome organization. Recent remarkable progress in genome sequencing of Lepidoptera has revealed that syntenic gene order is extensively conserved across phylogenetically distant species. The ancestral karyotype of Lepidoptera is thought to be n=31; however, that of the most well-studied moth, Bombyx mori, is n=28, and diverse studies suggest that three chromosomal fusion events occurred in this lineage. To identify the boundaries between predicted ancient fusions involving B. mori chromosomes 11, 23 and 24, we constructed fluorescence in situ hybridization (FISH)-based chromosome maps of the European corn borer, Ostrinia nubilalis (n=31). We first determined a 511 Mb genomic sequence of the Asian corn borer, O. furnacalis, a congener of O. nubilalis, and isolated bacterial artificial chromosomes and fosmid clones that were expected to localize in candidate regions for the boundaries using these sequences. Combined with FISH and genetic analysis, we narrowed down the candidate regions to 40 kb-1.5 Mb, in strong agreement with a previous estimate based on the genome of a butterfly, Melitaea cinxia. The significant difference in the lengths of the candidate regions where no functional genes were observed may reflect the evolutionary time after fusion events.


Assuntos
Evolução Biológica , Mapeamento Cromossômico , Genoma de Inseto , Mariposas/genética , Sintenia , Animais , Cromossomos Artificiais Bacterianos , Genes de Insetos , Genótipo , Hibridização in Situ Fluorescente , Masculino , Telômero/genética , Zea mays
4.
ESMO Open ; 9(4): 102981, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38613908

RESUMO

BACKGROUND: Comprehensive genome profiling (CGP) serves as a guide for suitable genomically matched therapies for patients with cancer. However, little is known about the impact of the timing and types of cancer on the therapeutic benefit of CGP. MATERIALS AND METHODS: A single hospital-based pan-cancer prospective study (TOP-GEAR; UMIN000011141) was conducted to examine the benefit of CGP with respect to the timing and types of cancer. Patients with advanced solid tumors (>30 types) who either progressed with or without standard treatments were genotyped using a single CGP test. The subjects were followed up for a median duration of 590 days to examine therapeutic response, using progression-free survival (PFS), PFS ratio, and factors associated with therapeutic response. RESULTS: Among the 507 patients, 62 (12.2%) received matched therapies with an overall response rate (ORR) of 32.3%. The PFS ratios (≥1.3) were observed in 46.3% (19/41) of the evaluated patients. The proportion of subjects receiving such therapies in the rare cancer cohort was lower than that in the non-rare cancer cohort (9.6% and 17.4%, respectively; P = 0.010). However, ORR of the rare cancer patients was higher than that in the non-rare cancer cohort (43.8% and 20.0%, respectively; P = 0.046). Moreover, ORR of matched therapies in the first or second line after receiving the CGP test was higher than that in the third or later lines (62.5% and 21.7%, respectively; P = 0.003). Rare cancer and early-line treatment were significantly and independently associated with ORR of matched therapies in multivariable analysis (P = 0.017 and 0.004, respectively). CONCLUSION: Patients with rare cancer preferentially benefited from tumor mutation profiling by increasing the chances of therapeutic response to matched therapies. Early-line treatments after profiling increase the therapeutic benefit, irrespective of tumor types.


Assuntos
Neoplasias , Medicina de Precisão , Humanos , Neoplasias/genética , Neoplasias/tratamento farmacológico , Feminino , Medicina de Precisão/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Adulto , Idoso de 80 Anos ou mais , Intervalo Livre de Progressão , Adulto Jovem , Doenças Raras/genética , Doenças Raras/tratamento farmacológico , Genômica/métodos
5.
Opt Express ; 21(6): 6889-94, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23546071

RESUMO

n-channel body-tied partially depleted metal-oxide-semiconductor field-effect transistors (MOSFETs) were fabricated for large current applications on a silicon-on-insulator wafer with photonics-oriented specifications. The MOSFET can drive an electrical current as large as 20 mA. We monolithically integrated this MOSFET with a 2 × 2 Mach-Zehnder interferometer optical switch having thermo-optic phase shifters. The static and dynamic performances of the integrated device are experimentally evaluated.


Assuntos
Interferometria/instrumentação , Refratometria/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Silício/química , Transistores Eletrônicos , Condutividade Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Temperatura Alta , Fótons , Integração de Sistemas
6.
Minerva Gastroenterol Dietol ; 59(2): 187-203, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23831909

RESUMO

MicroRNAs (miRNAs) are small, noncoding RNA molecules that regulate gene expression post-transcriptionally through complementary base pairing with thousands of messenger RNAs. Although the target genes and precise biological functions of individual miRNAs remain largely unknown, miRNAs are speculated to play important roles in diverse biological processes in both normal and pathological states. The liver is a vital organ that plays major roles in a number of physiological functions. Recent advances in the study of liver miRNAs using gene-modified mice or in vivo nucleic acid delivery to overexpress specific miRNAs or inhibit miRNA functions have revealed the crucial biological roles of individual miRNAs in physiologically essential liver functions in vivo. Because miRNA-based strategies are being applied to clinical therapeutics, the importance of precise knowledge of miRNA functions cannot be underestimated, not only from a scientific point of view, but also from a clinical perspective to make the most of such drugs and avoid unexpected harmful effects. The aims of this review are to describe current knowledge regarding both known and as-yet-undiscovered molecular aspects of the biological roles of miRNAs in the liver, with a special emphasis on lipid, glucose, drug, and iron metabolism as vital functions of the liver as well as important therapeutic targets.


Assuntos
Fígado/metabolismo , MicroRNAs/fisiologia , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos/genética
7.
Trends Cell Biol ; 11(12): 497-503, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11719056

RESUMO

Proteins, RNAs and even large macromolecular complexes are transported into and out of nuclei with remarkable rapidity and specificity. Nucleocytoplasmic transport must therefore be efficient and selective. Characterization of the roles of the importin beta family of transport receptors and of the Ran GTPase has showed how these characteristics can be achieved, but there are many examples of nucleocytoplasmic transport that do not fit this model. Here, we discuss current understanding of various transport mechanisms and evaluate cases in which the molecules and mechanisms underlying nucleocytoplasmic transport are used to carry out important cellular functions in the absence of a nucleus.


Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Transporte Nucleocitoplasmático , Proteínas de Ligação a RNA/metabolismo , beta Carioferinas/metabolismo , Proteína ran de Ligação ao GTP/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Cromossomos/metabolismo , Humanos , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Fatores de Transcrição/metabolismo
8.
J Environ Radioact ; 196: 133-140, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30453130

RESUMO

The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident has caused significant radionuclide contamination. Pu isotopes at the level of GBq were released from the damaged reactors to terrestrial and marine ecosystems. In this work, 35 samples were collected at different locations of Fukushima. Samples consisted of three types, soil, forest litter and alluvial dust (road dust, sludges from drainage systems and below gutter pipe outflows). The obtained activity ratios of 238Pu/(239+240)Pu ranged from 0.030 to 1.86. 14 of our samples contained trace amounts of Pu originating from the damaged reactors (2SM verification). Our study identified a few previously unknown "hot spots" of 238Pu/(239+240)Pu activity ratio localized in an area between 15 and 30 km in the northwest direction from the FDNPP. Additionally, results obtained in this study combined with previously published data allowed us to prepare a map of spatial distribution of the Pu isotope fingerprints (238Pu/(239+240)Pu) in Fukushima Prefecture.


Assuntos
Acidente Nuclear de Fukushima , Plutônio/análise , Monitoramento de Radiação , Poluentes Radioativos/análise , Japão
9.
Kidney Int ; 73(8): 926-32, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18256598

RESUMO

Phosphorylation of tyrosine residue (Y1204) of rat nephrin by Fyn kinase allows Nck adaptor protein binding to nephrin motifs, which include the phosphorylated tyrosine. This phosphorylation-dependent switch induces actin polymerization in a cell culture system. Here, we generated an antibody recognizing phosphorylated nephrin at the Nck binding sites pY1204 and pY1228 to determine the phosphorylation status of nephrin using a rat model of puromycin aminonucleoside-induced nephrosis. Changes in globular actin (G-actin) and filamentous actin (F-actin) contents in isolated glomeruli were measured by western blot. Before experimental nephrosis, both Y1204 and Y1228 were phosphorylated, and most of the actin was filamentous. Before the onset of overt proteinuria, however, phosphorylation of both Y1204 and Y1228 rapidly decreased and became almost undetectable. During this period, the amount of F-actin in glomeruli began to decrease, whereas G-actin increased. Phosphorylation of nephrin at Y1228 in glomeruli of patients with minimal change nephrosis was significantly decreased compared with that in normal glomeruli. Our study suggests that tyrosine phosphorylation of nephrin by regulating F-actin formation may be important for the maintenance of normal podocyte morphology and function.


Assuntos
Actinas/metabolismo , Glomérulos Renais/metabolismo , Proteínas de Membrana/metabolismo , Nefrose/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Anticorpos/isolamento & purificação , Antimetabólitos Antineoplásicos/toxicidade , Células COS , Chlorocebus aethiops , Citoesqueleto/metabolismo , Humanos , Proteínas de Membrana/imunologia , Nefrose/induzido quimicamente , Fosforilação , Podócitos/metabolismo , Puromicina Aminonucleosídeo/toxicidade , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
10.
Acta Radiol ; 49(2): 197-203, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18300147

RESUMO

BACKGROUND: The pathogenesis of cerebrospinal fluid (CSF) hypovolemia is supposed to be caused by CSF leakage through small dural defects. PURPOSE: To compare source three-dimensional (3D) fast spin-echo (FSE) images of magnetic resonance (MR) myelography with radionuclide cisternography findings, and to evaluate the feasibility of MR myelography in the detection of CSF leakage. MATERIAL AND METHODS: A total of 67 patients who were clinically suspected of CSF hypovolemia underwent indium-111 radionuclide cisternography, and 27 of those who had direct findings of CSF leakage were selected for evaluation. MR myelography with 3D FSE sequences (TR/TE 6000/203 ms) was performed at the lumbar spine for all patients. We evaluated source images and maximum intensity projection (MIP) images of MR myelography, and the findings were correlated with radionuclide cisternography findings. MR myelography of five healthy volunteers was used as a reference. The MR visibility of the CSF leakage was graded as definite (leakage clearly visible), possible (leakage poorly seen), or absent (not shown). RESULTS: CSF leakage was identified with source 3D FSE images in 22 (81.5%) of 27 patients. Of the 22 patients, 16 were graded as definite and six were graded as possible. For the definite cases, 3D FSE images clearly showed the extent of the leaked CSF in the paraspinal structures. In the remaining five patients with absent findings, radionuclide cisternography showed only slight radionuclide activity out of the arachnoid space. CONCLUSION: Source 3D FSE images of MR myelography seem useful in the detection of CSF leakage. Invasive radionuclide cisternography may be reserved for equivocal cases only.


Assuntos
Imagem Ecoplanar/métodos , Imageamento Tridimensional/métodos , Derrame Subdural/diagnóstico , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Hipovolemia/diagnóstico , Hipovolemia/etiologia , Radioisótopos de Índio , Hipotensão Intracraniana/diagnóstico , Hipotensão Intracraniana/etiologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Cintilografia , Valores de Referência , Estudos Retrospectivos , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Fatores de Tempo
11.
Nat Neurosci ; 4(12): 1238-43, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11713472

RESUMO

Here we introduce a strategy in which pharmacology is used to induce the effects of recessive mutations. For example, mice heterozygous for a null mutation of the K-ras gene (K-ras+/-) show normal hippocampal mitogen-activated protein kinase (MAPK) activation, long-term potentiation (LTP) and contextual conditioning. However, a dose of a mitogen-activated/extracellular-signal-regulated kinase (MEK) inhibitor, ineffective in wild-type controls, blocks MAPK activation, LTP and contextual learning in K-ras+/- mutants. These indicate that K-Ras/MEK/MAPK signaling is critical in synaptic and behavioral plasticity. A subthreshold dose of NMDA receptor antagonists triggered a contextual learning deficit in mice heterozygous for a point mutation (T286A) in the alphaCaMKII gene, but not in K-ras+/- mutants, demonstrating the specificity of the synergistic interaction between the MEK inhibitor and the K-ras+/- mutation. This pharmacogenetic approach combines the high temporal specificity that pharmacological manipulations offer, with the molecular specificity of genetic disruptions.


Assuntos
Genes ras/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Memória/efeitos dos fármacos , Mutação/efeitos dos fármacos , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Axônios/efeitos dos fármacos , Axônios/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas Quinases Dependentes de Cálcio-Calmodulina/deficiência , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Medo/efeitos dos fármacos , Medo/fisiologia , Feminino , Genes ras/fisiologia , Heterozigoto , Hipocampo/metabolismo , Aprendizagem/fisiologia , Potenciação de Longa Duração/fisiologia , MAP Quinase Quinase 1 , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Memória/fisiologia , Camundongos , Camundongos Knockout , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação/fisiologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo
12.
J Int Med Res ; 36(3): 489-95, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18534130

RESUMO

Nocturnal vocalization is frequent in Parkinson's disease patients with rapid eye movement (REM) sleep behaviour disorder (RBD). We investigated the frequency of nocturnal vocalization and other sleep problems in patients with pure autonomic failure (PAF) and compared the results with idiopathic Parkinson's disease (IPD) and dementia with Lewy bodies (DLB). We interviewed consecutive patient-caregiver pairs with PAF (n = 13), IPD (n = 200) and DLB (n = 19), and ischaemic stroke patients (controls, n = 43). Nocturnal vocalization was similarly frequent in PAF, IPD and DLB. Other dream enactments and vivid dreams also were more frequent in PAF, IPD and DLB compared with controls. Excessive night-time awakenings and daytime sleepiness were frequent in IPD but rare in PAF and controls. Clinical manifestation of sleep disturbances, at least of RBD-like symptoms including nocturnal vocalization and other dream enactments, may occur in PAF, as in IPD and DLB.


Assuntos
Doenças do Sistema Nervoso Autônomo/complicações , Escuridão , Transtornos do Sono-Vigília/complicações , Idoso , Estudos de Casos e Controles , Demência/complicações , Feminino , Humanos , Corpos de Lewy/patologia , Masculino , Doença de Parkinson/complicações
13.
J Hosp Infect ; 99(1): 31-35, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29258919

RESUMO

BACKGROUND: Several reports have been published regarding cost increases attributable to surgical site infections (SSIs) in Europe and the USA. However, such studies have been limited in Japan. AIM: To evaluate the economic burden of colorectal SSIs on hospitals in Japan. METHODS: This study was undertaken at a Japanese university hospital. Amongst 265 patients who had undergone colorectal surgery in the Department of Coloproctological Surgery between November 2014 and March 2016, 16 patients who developed SSIs and could be allocated a diagnosis procedure combination code were selected as SSI cases. Individual SSI cases were matched to non-SSI cases based on a combination of surgical category, age band, sex, wound class, presence of stoma and risk index. Median length of stay (LOS) and piecework reference cost were compared between SSI episodes and non-SSI episodes. FINDINGS: The median LOS for patients with SSI and without SSI was 25.5 [interquartile range (IQR) 21.5-39.3] and 16.5 (IQR 12.5-18.5) days, respectively (P<0.01). The median piecework reference cost for patients with SSI and without SSI was ¥842,155 (IQR ¥716,423-1,388,968) and ¥575,795 (IQR ¥529,638-680,105), respectively (P<0.01). CONCLUSION: SSIs led to a significant increase in LOS and economic burden. Although the SSI episodes appear to be more profitable than the non-SSI episodes, the economic profit for SSI episodes was less than that for non-SSI episodes in the observation period, when opportunity costs were taken into account.


Assuntos
Cirurgia Colorretal/efeitos adversos , Custos Hospitalares , Hospitais Universitários , Infecção da Ferida Cirúrgica/economia , Infecção da Ferida Cirúrgica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Japão/epidemiologia , Tempo de Internação , Masculino , Pessoa de Meia-Idade
14.
Cell Death Differ ; 13(4): 551-63, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16273081

RESUMO

We previously reported that 8-oxoguanine (8-oxoG) accumulates in the cytoplasm of dopamine neurons in the substantia nigra of patients with Parkinson's disease and the expression of MTH1 carrying an oxidized purine nucleoside triphosphatase activity increases in these neurons, thus suggesting that oxidative damage in nucleic acids is involved in dopamine neuron loss. In the present study, we found that levels of 8-oxoG in cellular DNA and RNA increased in the mouse nigrostriatal system during the tyrosine hydroxylase (TH)-positive dopamine neuron loss induced by the administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). MTH1-null mice exhibited a greater accumulation of 8-oxoG in mitochondrial DNA accompanied by a more significant decrease in TH and dopamine transporter immunoreactivities in the striatum after MPTP administration, than in wild-type mice. We thus demonstrated that MTH1 protects the dopamine neurons from oxidative damage in the nucleic acids, especially in the mitochondrial DNA of striatal nerve terminals of dopamine neurons.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , DNA Mitocondrial/metabolismo , Dopamina/metabolismo , Guanina/análogos & derivados , Neurônios/enzimologia , Transtornos Parkinsonianos/enzimologia , Monoéster Fosfórico Hidrolases/metabolismo , Animais , Corpo Estriado/enzimologia , Corpo Estriado/patologia , Enzimas Reparadoras do DNA/deficiência , Enzimas Reparadoras do DNA/genética , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Guanina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/patologia , Estresse Oxidativo , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/patologia , Monoéster Fosfórico Hidrolases/deficiência , Monoéster Fosfórico Hidrolases/genética , RNA/metabolismo , Substância Negra/enzimologia , Substância Negra/patologia , Tirosina 3-Mono-Oxigenase/metabolismo
15.
Curr Biol ; 9(2): R66-9, 1999 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-10021358

RESUMO

The protein Mei2 performs at least two functions required in fission yeast for the switch from mitotic to meiotic cell cycles. One of these functions also requires meiRNA. It appears that meiRNA targets Mei2 to the nucleus, where it can promote the first meiotic division.


Assuntos
Proteínas Fúngicas/metabolismo , Meiose/genética , Proteínas de Ligação a RNA/metabolismo , RNA/genética , Proteínas de Schizosaccharomyces pombe , Transporte Biológico , Proteínas Fúngicas/genética , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/genética
16.
J Clin Invest ; 95(3): 1363-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7883983

RESUMO

The endothelium has the capacity to modulate vascular structure in response to hemodynamic stimuli. We tested the hypothesis that exposure of the endothelium to increased laminar shear stress induces the expression of TGF beta 1 via a signal transduction pathway modulated by K+ channel currents. Although TGF beta 1 is normally secreted in a latent, inactive form, exposure of cultured endothelial cells to steady laminar shear stress (20 dynes/cm2) induced increased generation of biologically active TGF beta 1. This increase in active TGF beta 1 was associated with a sustained increase in TGF beta 1 mRNA expression within 2 h of stimulation. TGF beta 1 mRNA levels increased in direct proportion to the intensity of the shear stress within the physiologic range. The effect of shear stress on TGF beta 1 mRNA expression was regulated at the transcriptional level as defined by nuclear run-off studies and transient transfection of a TGF beta 1 promoter-reporter gene construct. Blockade of endothelial K+ channels with tetraethylammonium significantly inhibited: activation of TGF beta 1 gene transcription; increase in steady state mRNA levels; and generation of active TGF beta 1 in response to shear stress. These data suggest that endothelial K+ channels and autocrine-paracrine TGF beta 1 may be involved in the mechanotransduction mechanisms mediating flow-induced vascular remodeling.


Assuntos
Endotélio Vascular/fisiologia , Canais de Potássio/metabolismo , Transdução de Sinais/fisiologia , Transcrição Gênica , Fator de Crescimento Transformador beta/biossíntese , Animais , Aorta/citologia , Bioensaio , Northern Blotting , Bovinos , Núcleo Celular/metabolismo , Células Cultivadas , Regulação da Expressão Gênica , Genes Reporter , Estimulação Física , Bloqueadores dos Canais de Potássio , RNA Mensageiro/análise , Tetraetilamônio , Compostos de Tetraetilamônio/farmacologia , Fator de Crescimento Transformador beta/genética
17.
Mol Cell Biol ; 14(11): 7611-20, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7935475

RESUMO

In the budding yeast Saccharomyces cerevisiae, a number of PRP genes known to be involved in pre-mRNA processing have been genetically identified and cloned. Three PRP genes (PRP2, PRP16, and PRP22) were shown to encode putative RNA helicases of the family of proteins with DEAH boxes. However, any such splicing factor containing the helicase motifs in vertebrates has not been identified. To identify human homologs of this family, we designed PCR primers corresponding to the highly conserved region of the DEAH box protein family and successfully amplified five cDNA fragments, using HeLa poly(A)+ RNA as a substrate. One fragment, designated HRH1 (human RNA helicase 1), is highly homologous to Prp22, which was previously shown to be involved in the release of spliced mRNAs from the spliceosomes. Expression of HRH1 in a S. cerevisiae prp22 mutant can partially rescue its temperature-sensitive phenotype. These results strongly suggest that HRH1 is a functional human homolog of the yeast Prp22 protein. Interestingly, HRH1 but not Prp22 contains an arginine- and serine-rich domain (RS domain) which is characteristic of some splicing factors, such as members of the SR protein family. We could show that HRH1 can interact in vitro and in the yeast two-hybrid system with members of the SR protein family through its RS domain. We speculate that HRH1 might be targeted to the spliceosome through this interaction.


Assuntos
Proteínas Fúngicas/genética , RNA Nucleotidiltransferases/genética , Proteínas de Saccharomyces cerevisiae , Sequência de Aminoácidos , Sequência de Bases , RNA Helicases DEAD-box , DNA/genética , Primers do DNA/genética , DNA Fúngico/genética , Genes Fúngicos , Teste de Complementação Genética , Células HeLa , Humanos , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , RNA Helicases , Precursores de RNA/metabolismo , Splicing de RNA/genética , Fatores de Processamento de RNA , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Spliceossomos/metabolismo
18.
Mol Cell Biol ; 19(3): 2051-60, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10022892

RESUMO

The gene encoding the Na/I symporter (NIS) is expressed at high levels only in thyroid follicular cells, where its expression is regulated by the thyroid-stimulating hormone via the second messenger, cyclic AMP (cAMP). In this study, we demonstrate the presence of an enhancer that is located between nucleotides -2264 and -2495 in the 5'-flanking region of the NIS gene and that recapitulates the most relevant aspects of NIS regulation. When fused to either its own or a heterologous promoter, the NIS upstream enhancer, which we call NUE, stimulates transcription in a thyroid-specific and cAMP-dependent manner. The activity of NUE depends on the four most relevant sites, identified by mutational analysis. The thyroid-specific transcription factor Pax8 binds at two of these sites. Mutations that interfere with Pax8 binding also decrease transcriptional activity of the NUE. Furthermore, expression of Pax8 in nonthyroid cells results in transcriptional activation of NUE, strongly suggesting that the paired-domain protein Pax8 plays an important role in NUE activity. The NUE responds to cAMP in both protein kinase A-dependent and -independent manners, indicating that this enhancer could represent a novel type of cAMP responsive element. Such a cAMP response requires Pax8 but also depends on the integrity of a cAMP responsive element (CRE)-like sequence, thus suggesting a functional interaction between Pax8 and factors binding at the CRE-like site.


Assuntos
Proteínas de Transporte/genética , AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Proteínas de Membrana/genética , Simportadores , Glândula Tireoide/metabolismo , Transativadores/metabolismo , Transcrição Gênica , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Proteínas de Ligação a DNA/genética , Dados de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fator de Transcrição PAX8 , Fatores de Transcrição Box Pareados , Ratos , Sequências Reguladoras de Ácido Nucleico , Glândula Tireoide/citologia , Fator Nuclear 1 de Tireoide , Transativadores/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional
19.
Mol Cell Biol ; 19(9): 6276-85, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10454574

RESUMO

CRM1 is an export receptor mediating rapid nuclear exit of proteins and RNAs to the cytoplasm. CRM1 export cargoes include proteins with a leucine-rich nuclear export signal (NES) that bind directly to CRM1 in a trimeric complex with RanGTP. Using a quantitative CRM1-NES cargo binding assay, significant differences in affinity for CRM1 among natural NESs are demonstrated, suggesting that the steady-state nucleocytoplasmic distribution of shuttling proteins could be determined by the relative strengths of their NESs. We also show that a trimeric CRM1-NES-RanGTP complex is disassembled by RanBP1 in the presence of RanGAP, even though RanBP1 itself contains a leucine-rich NES. Selection of CRM1-binding proteins from Xenopus egg extract leads to the identification of an NES-containing DEAD-box helicase, An3, that continuously shuttles between the nucleus and the cytoplasm. In addition, we identify the Xenopus homologue of the nucleoporin CAN/Nup214 as a RanGTP- and NES cargo-specific binding site for CRM1, suggesting that this nucleoporin plays a role in export complex disassembly and/or CRM1 recycling.


Assuntos
Proteínas de Transporte/metabolismo , Carioferinas , Complexo de Proteínas Formadoras de Poros Nucleares , Proteínas Nucleares/metabolismo , RNA Helicases/metabolismo , Receptores Citoplasmáticos e Nucleares , Sequência de Aminoácidos , Animais , Sequência de Bases , Transporte Biológico Ativo , Núcleo Celular/metabolismo , Primers do DNA/genética , Feminino , Proteínas de Ligação ao GTP/metabolismo , Humanos , Técnicas In Vitro , Modelos Biológicos , Dados de Sequência Molecular , Oócitos/metabolismo , Ligação Proteica , RNA Helicases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Xenopus , Proteína ran de Ligação ao GTP , Proteína Exportina 1
20.
Cell Death Differ ; 12(8): 1078-96, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15861185

RESUMO

Transient forebrain ischemia causes selective induction of DeltaFosB, an AP-1 (activator protein-1) subunit, in cells within the ventricle wall or those in the dentate gyrus in the rat brain prior to neurogenesis, followed by induction of nestin, a marker for neuronal precursor cells, or galectin-1, a beta-galactoside sugar-binding lectin. The adenovirus-mediated expression of FosB or DeltaFosB induced expression of nestin, glial fibrillary acidic protein and galectin-1 in rat embryonic cortical cells. DeltaFosB-expressing cells exhibited a significantly higher survival and proliferation after the withdrawal of B27 supplement than the control or FosB-expressing cells. The decline in the DeltaFosB expression in the survivors enhanced the MAP2 expression. The expression of DeltaFosB in cells within the ventricle wall of the rat brain also resulted in an elevated expression of nestin. We therefore conclude that DeltaFosB can promote the proliferation of quiescent neuronal precursor cells, thus enhancing neurogenesis after transient forebrain ischemia.


Assuntos
Encéfalo/metabolismo , Galectina 1/fisiologia , Ataque Isquêmico Transitório/metabolismo , Proteínas Proto-Oncogênicas c-fos/fisiologia , Fatores de Transcrição/fisiologia , Adenoviridae/genética , Animais , Células Cultivadas , Córtex Cerebral/metabolismo , Embrião de Mamíferos , Galectina 1/biossíntese , Proteína Glial Fibrilar Ácida/biossíntese , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/biossíntese , Masculino , Camundongos , Microscopia Confocal , Microscopia de Fluorescência , Proteínas do Tecido Nervoso/biossíntese , Nestina , Neurônios/citologia , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-fos/genética , Coelhos , Ratos , Ratos Endogâmicos SHR , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
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