Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 244
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Allergy ; 73(9): 1881-1891, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29528494

RESUMO

BACKGROUND: Barrier dysfunction is an important feature of atopic dermatitis (AD) in which IL-4 and IL-13, signature type 2 cytokines, are involved. Periostin, a matricellular protein induced by IL-4 or IL-13, plays a crucial role in the onset of allergic skin inflammation, including barrier dysfunction. However, it remains elusive how periostin causes barrier dysfunction downstream of the IL-13 signal. METHODS: We systematically identified periostin-dependent expression profile using DNA microarrays. We then investigated whether IL-24 downregulates filaggrin expression downstream of the IL-13 signals and whether IL-13-induced IL-24 expression and IL-24-induced downregulation of filaggrin expression are dependent on the JAK/STAT pathway. To build on the significance of in vitro findings, we investigated expression of IL-24 and activation of STAT3 in mite-treated mice and in AD patients. RESULTS: We identified IL-24 as an IL-13-induced molecule in a periostin-dependent manner. Keratinocytes are the main IL-24-producing tissue-resident cells stimulated by IL-13 in a periostin-dependent manner via STAT6. IL-24 significantly downregulated filaggrin expression via STAT3, contributing to barrier dysfunction downstream of the IL-13/periostin pathway. Wild-type mite-treated mice showed significantly enhanced expression of IL-24 and activation of STAT3 in the epidermis, which disappeared in both STAT6-deficient and periostin-deficient mice, suggesting that these events are downstream of both STAT6 and periostin. Moreover, IL-24 expression was enhanced in the epidermis of skin tissues taken from AD patients. CONCLUSIONS: The IL-13/periostin pathway induces IL-24 production in keratinocytes, playing an important role in barrier dysfunction in AD.


Assuntos
Moléculas de Adesão Celular/metabolismo , Dermatite Atópica/etiologia , Dermatite Atópica/metabolismo , Epiderme/imunologia , Epiderme/metabolismo , Interleucina-13/metabolismo , Interleucinas/metabolismo , Adolescente , Adulto , Idoso , Animais , Biomarcadores , Moléculas de Adesão Celular/genética , Linhagem Celular , Criança , Pré-Escolar , Dermatite Atópica/patologia , Modelos Animais de Doenças , Epiderme/patologia , Feminino , Proteínas Filagrinas , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Lactente , Interleucina-13/genética , Interleucinas/genética , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Fator de Transcrição STAT6/metabolismo , Transdução de Sinais , Adulto Jovem
2.
Photochem Photobiol Sci ; 17(6): 846-853, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29808210

RESUMO

Phosphorescence lifetime imaging methods using oxygen-sensitive probes are very useful for visualizing the oxygen status of living cells and tissues with high spatial resolution. We aim to develop a useful oxygen detection technique combining a phosphorescent oxygen probe and an optimal detection method. Herein we present a biological oxygen imaging method using a microscope equipped with a gated intensified charge-coupled device (ICCD) camera as a detector and an Ir(iii) complex as a phosphorescent oxygen probe. Microscopic luminescence images of monolayer HT-29 cells (human colorectal adenocarcinoma cells) obtained using the cell-penetrating Ir(iii) complex BTPDM1 and an inverted microscope demonstrated that this method allowed visualization of the oxygen gradient produced in a monolayer of cultured cells when the monolayer is covered with a thin coverslip. Furthermore, combining the IR-emitting Ir(iii) complex DTTPH-PEG24 with a macrozoom microscope equipped with a gated ICCD camera enabled both the visualization of retinal vessels near the optic disc and the monitoring of oxygen level changes in a rabbit retina upon changing the inhaled oxygen content.

4.
Science ; 248(4954): 477-80, 1990 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-17815599

RESUMO

Pigeon pea was shown to be more efficient at utilizing iron-bound phosphorus (Fe-P) than several other crop species. This ability is attributed to root exudates, in particular piscidic acid and its p-O-methyl derivative, which release phosphorus from Fe-P by chelating Fe(3+). Pigeon pea is normally intercropped with cereals under low-input conditions in the Indian subcontinent. Although pigeon pea can utilize the relatively insoluble Fe-P, intercropped cereals must rely on the more soluble calcium-bound phosphorus. This finding suggests that cultivation of pigeon pea increases total phosphorus availability in cropping systems with low available phosphorus.

5.
Pediatr Hematol Oncol ; 25(6): 607-13, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18728980

RESUMO

A 20-year-old female developed a relapse of B-precursor acute lymphoblastic leukemia (ALL) as a mass in her left breast after 6 years of maintained continuous complete remission. No leukemic lesions were identified in other sites such as the bone marrow or cerebrospinal fluid. The relapsed leukemic cells in the breast revealed the same immunophenotypes (CD10(+), CD19(+), CD20(+), HLA-DR(+), CD34(+)) as those of the onset ALL cells in the bone marrow. A literature survey found 10 other cases of ALL relapse in the breast without bone marrow involvement, mostly consisting of adolescent girls. Including the present report, a total of 11 cases were analyzed; the onset ages of ALL were a median of 16.5 (range 5-50) years old and the ages of relapse in the breast a median of 20 (range 12-51) years old. Data suggest that, although rare, the breast could become one of the extramedullary relapse sites of ALL developed in adolescent girls.


Assuntos
Neoplasias da Mama/secundário , Recidiva Local de Neoplasia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Adulto , Feminino , Humanos
6.
J Environ Radioact ; 186: 23-33, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28869070

RESUMO

Processes of vertical and lateral migration lead to gradual reduction in contamination of catchment soil, particularly its top layer. The reduction can be considered as natural attenuation. This, in turn, results in a gradual decrease of radiocesium activity concentrations in the surface runoff and river water, in both dissolved and particulate forms. The purpose of this research is to study the dynamics of Fukushima-derived radiocesium in undisturbed soils and floodplain deposits exposed to erosion and sedimentation during floods. Combined observations of radiocesium vertical distribution in soil and sediment deposition on artificial lawn-grass mats on the Niida River floodplain allowed us to estimate both annual mean sediment accumulation rates and maximum sedimentation rates corresponding to an extreme flood event during Tropical Storm Etau, 6-11 September 2015. Dose rates were reduced considerably for floodplain sections with high sedimentation because the top soil layer with high radionuclide contamination was eroded and/or buried under cleaner fresh sediments produced mostly due to bank erosion and sediments movements. Rate constants of natural attenuation on the sites of the Takase River and floodplain of Niida River was found to be in range 0.2-0.4 year-1. For the site in the lower reach of the Niida River, collimated shield dose readings from soil surfaces slightly increased during the period of observation from February to July 2016. Generally, due to more precipitation, steeper slopes, higher temperatures and increased biological activities in soils, self-purification of radioactive contamination in Fukushima associated with vertical and lateral radionuclide migration is faster than in Chernobyl. In many cases, monitored natural attenuation along with appropriate restrictions seems to be optimal option for water remediation in Fukushima contaminated areas.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Japão , Solo/química
7.
Mol Cell Biol ; 17(3): 1417-24, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9032268

RESUMO

The E2A-HLF fusion gene, created by the t(17;19)(q22;p13) chromosomal translocation in pro-B lymphocytes, encodes an oncogenic protein in which the E2A trans-activation domain is linked to the DNA-binding and protein dimerization domain of hepatic leukemia factor (HLF), a member of the proline- and acidic amino acid-rich (PAR) subfamily of bZIP transcription factors. This fusion product binds to its DNA recognition site not only as a homodimer but also as a heterodimer with HLF and two other members of the PAR bZIP subfamily, thyrotroph embryonic factor (TEF) and albumin promoter D-box binding protein (DBP). Thus, E2A-HLF could transform cells by direct regulation of downstream target genes, acting through homodimeric or heterodimeric complexes, or by sequestering normal PAR proteins into nonfunctional heterocomplexes (dominant-negative interference). To distinguish among these models, we constructed mutant E2A-HLF proteins in which the leucine zipper domain of HLF was extended by one helical turn or altered in critical charged amino acids, enabling the chimera to bind to DNA as a homodimer but not as a heterodimer with HLF or other PAR proteins. When introduced into NIH 3T3 cells in a zinc-inducible vector, each of these mutants induced anchorage-independent growth as efficiently as unaltered E2A-HLF, indicating that the chimeric oncoprotein can transform cells in its homodimeric form. Transformation also depended on an intact E2A activator region, providing further support for a gain-of-function contribution to oncogenesis rather than one based on a dominant-interfering or dominant-negative mechanism. Thus, the tumorigenic effects of E2A-HLF and its mutant forms in NIH 3T3 cells favor a straightforward model in which E2A-HLF homodimers bind directly to promoter/enhancer elements of downstream target genes and alter their patterns of expression in early B-cell progenitors.


Assuntos
Transformação Celular Neoplásica , Proteínas de Ligação a DNA/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Fatores de Transcrição/metabolismo , Células 3T3 , Animais , Fatores de Transcrição de Zíper de Leucina Básica , DNA/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Dimerização , Regulação Neoplásica da Expressão Gênica/fisiologia , Zíper de Leucina , Camundongos , Mutação , Proteínas de Fusão Oncogênica/química , Proteínas de Fusão Oncogênica/genética , RNA Mensageiro/análise , Fatores de Transcrição/química , Fatores de Transcrição/genética
8.
Mol Cell Biol ; 15(6): 3247-55, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7760820

RESUMO

The E2A-HLF fusion gene, formed by the t(17;19)(q22;p13) translocation in childhood acute pro-B-cell leukemia, encodes a hybrid protein that contains the paired trans-activation domains of E2A (E12/E47) linked to the basic region/leucine zipper DNA-binding and dimerization domain of hepatic leukemia factor (HLF). To assess the transforming potential of this novel gene, we introduced it into NIH 3T3 murine fibroblasts by using an expression vector that also contained the neomycin resistance gene. Cells selected for resistance to the neomycin analog G418 formed aberrant colonies in monolayer cultures, marked by increased cell density and altered morphology. Transfected cells also grew readily in soft agar, producing colonies whose sizes correlated with E2A-HLF expression levels. Subclones expanded from colonies with high levels of the protein reproducibly formed tumors in nude mice and grew to higher plateau-phase cell densities in reduced-serum conditions than did parental NIH 3T3 cells. By contrast, NIH 3T3 cells expressing mutant E2A-HLF proteins that lacked either of the bipartite E2A trans-activation domains or the HLF leucine zipper domain failed to show oncogenic properties, including anchorage-independent cell growth. Thus, both of the E2A trans-activation motifs and the HLF leucine zipper dimerization domain are essential for the transforming potential of the chimeric E2A-HLF protein, suggesting a model in which aberrant regulation of the expression pattern of downstream target genes contributes to leukemogenesis.


Assuntos
Proteínas E2 de Adenovirus/genética , Transformação Celular Neoplásica/metabolismo , Proteínas de Ligação a DNA/genética , Zíper de Leucina/genética , Proteínas de Fusão Oncogênica/genética , Células 3T3 , Proteínas E2 de Adenovirus/farmacologia , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina Básica , Proteínas de Ligação a DNA/farmacologia , Camundongos , Dados de Sequência Molecular , Proteínas de Fusão Oncogênica/farmacologia , Plasmídeos , Dobramento de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
9.
Mol Cell Biol ; 19(4): 2754-62, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10082541

RESUMO

Hematopoietic cells require cytokine-initiated signals for survival as well as proliferation. The pathways that transduce these signals, ensuring timely regulation of cell fate genes, remain largely undefined. The NFIL3 (E4BP4) transcription factor, Bcl-xL, and constitutively active mutants of components in Ras signal transduction pathways have been identified as key regulation proteins affecting murine interleukin-3 (IL-3)-dependent cell survival. Here we show that expression of NFIL3 is regulated by oncogenic Ras mutants through both the Raf-mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways. NFIL3 inhibits apoptosis without affecting Bcl-xL expression. By contrast, Bcl-xL levels are regulated through the membrane proximal portion in the cytoplasmic domain of the receptor (betac chain), which is shared by IL-3 and granulocyte-macrophage colony-stimulating factor. Activation of either pathway alone is insufficient to ensure cell survival, indicating that multiple independent signal transduction pathways mediate the survival of developing B-lymphoid cells.


Assuntos
Apoptose , Linfócitos B/citologia , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Hematopoéticas/citologia , Interleucina-3/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linfócitos B/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Sobrevivência Celular , Relação Dose-Resposta a Droga , Fatores de Ligação G-Box , Células-Tronco Hematopoéticas/metabolismo , Camundongos , Modelos Imunológicos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais , Proteína bcl-X , Proteínas ras/metabolismo
10.
Nat Biotechnol ; 17(3): 282-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10096297

RESUMO

To improve the iron content of rice, we have transferred the entire coding sequence of the soybean ferritin gene into Oryza sativa (L. cv. Kita-ake) by Agrobacterium-mediated transformation. The rice seed-storage protein glutelin promoter, GluB-1, was used to drive expression of the soybean gene specifically in developing, self-pollinated seeds (T1 seeds) of transgenic plants, as confirmed by reverse transcription PCR analysis. Stable accumulation of the ferritin subunit in the rice seed was demonstrated by western blot analysis, and its specific accumulation in the endosperm by immunologic tissue printing. The iron content of T1 seeds was as much as threefold greater than that of their untransformed counterparts.


Assuntos
Ferritinas/genética , Ferro/metabolismo , Oryza/genética , Plantas Geneticamente Modificadas , Southern Blotting , Western Blotting , Ferritinas/metabolismo , Expressão Gênica , Imuno-Histoquímica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual , Transformação Genética
11.
Bone Marrow Transplant ; 37(1): 25-31, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16247416

RESUMO

The prognosis of patients with acute lymphoblastic leukemia (ALL) and central nervous system (CNS) relapse has historically been very poor. Although chemo-radiotherapy has improved outcomes, some patients still have a poor prognosis after CNS relapse. Therefore, allogeneic hematopoietic stem cell transplantation (allo-SCT) has recently become an option for treatment of CNS leukemia; however, information, particularly on the long-term outcome of transplant recipients, is limited. We performed allo-SCT in eight pediatric patients with ALL (n=7) or T-cell type non-Hodgkin's lymphoma (n=1), who had isolated CNS relapse. All patients survived for a median of 70.5 (range, 13-153) months after SCT. Sequelae developed late in some patients: mental retardation (IQ=47) in one patient, severe alopecia in two patients, limited chronic graft-versus-host-disease in three patients, and amenorrhea and/or hypothyroidism in three patients. Except for a pre-school child with post transplant CNS relapse, six out of seven patients show normal school/social performance. Our results clearly indicate a high cure rate of isolated CNS relapse by allo-SCT in pediatric lymphoid malignancies; however, there needs to be further studies to determine which are the appropriate candidates for transplantation and what is the best transplant regimen to achieve high cure rate and maintain good quality of life.


Assuntos
Neoplasias do Sistema Nervoso Central/terapia , Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Amenorreia/etiologia , Amenorreia/mortalidade , Neoplasias do Sistema Nervoso Central/complicações , Neoplasias do Sistema Nervoso Central/mortalidade , Neoplasias do Sistema Nervoso Central/secundário , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/mortalidade , Humanos , Hipotireoidismo/etiologia , Hipotireoidismo/mortalidade , Deficiência Intelectual/etiologia , Deficiência Intelectual/mortalidade , Linfoma de Células T/complicações , Linfoma de Células T/mortalidade , Linfoma de Células T/terapia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Qualidade de Vida , Recidiva , Transplante Homólogo
12.
Acta Physiol (Oxf) ; 218(3): 178-187, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27306326

RESUMO

AIM: A recent study demonstrated that FoxO3a was directly induced by the overexpression of Hsp72 in rat soleus muscle. However, whether heat stress treatment induces FoxO3a phosphorylation in rat skeletal muscle remains unclear. This study examined the effects of heat stress on the regulation of the FoxO3a signalling pathway in rat skeletal muscle. METHODS: Thirty-two male Wistar rats (15 weeks old) were randomly assigned into two groups; sedentary control group (Sed, n = 8) and experimental group (n = 24). After an overnight fast, one leg of each rat (HS leg) in the experimental group was immersed in hot water (43 °C) for 30 min, and the soleus and plantaris muscles in both legs were removed immediately (0 min), 30 min, 60 min, or 24 h after the heat stress (n = 6 each group). The contralateral, non-heated leg in the experimental group served as an internal control (CT leg). RESULTS: Heat stress treatment resulted in a significant increase in FoxO3a phosphorylation (Ser253) in the soleus and plantaris muscles of heat-stressed legs after 24 h. Hsp72 expression in heat-stressed legs was significantly higher at 60 min and 24 h in these muscles. Activation of the PTEN/Akt and MEK/ERK pathways was also observed in these muscles immediately after stress, but not at 24 h. There were no differences in FoxO1 and AMPKα phosphorylation in either muscle. CONCLUSION: Heat stress in rat skeletal muscle induces phosphorylation of FoxO3a signalling, and it may be related to Hsp72 upregulation, and the activation of the PTEN/Akt and MEK/ERK pathways.


Assuntos
Proteína Forkhead Box O3/metabolismo , Músculo Esquelético/metabolismo , Transdução de Sinais/fisiologia , Estresse Fisiológico/fisiologia , Animais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas de Choque Térmico HSP72/genética , Proteínas de Choque Térmico HSP72/metabolismo , Temperatura Alta , Masculino , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Wistar , Regulação para Cima
13.
Bone Marrow Transplant ; 35(6): 587-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15756284

RESUMO

A young female patient in a second remission of acute lymphoblastic leukemia underwent bone marrow transplantation after total body irradiation and high-dose cytarabine from her HLA-matched brother. Following successful engraftment, mixed chimerism was seen 75 days post transplant. The karyotype contained numerous abnormalities in residual recipient cells. Chromosomes 1, 7, 13, and X were significantly more affected than other chromosomes. The high-frequency breakpoints identified were 1p22.2, 5q31.2, and 13q14.2. Some karyotypes specific for leukemia, such as t(9;22)(q34.1;q11.2) and t(8;21)(q22.2;q22.2), not seen with the original disease, were also present. As the frequency of aberrant chromosomes increased markedly with time, donor leukocytes were infused 14 months after BMT, which effectively eradicated the abnormal karyotypes.


Assuntos
Células da Medula Óssea/patologia , Transplante de Medula Óssea/efeitos adversos , Aberrações Cromossômicas , Pré-Escolar , Células Clonais/patologia , Terapia Combinada , Feminino , Humanos , Cariotipagem , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Transplante Homólogo
14.
Phytochemistry ; 66(21): 2577-80, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16226774

RESUMO

Bioassay-guided investigation of the bark of Elaeocarpus parvifolius led to the isolation of three new ellagic acid derivatives, 4-O-methylellagic acid 3'-alpha-rhamnoside (2), 4-O-methylellagic acid 3'-(3''-O-acetyl)-alpha-rhamnoside (3), and 4-O-methylellagic acid 3'-(4''-O-acetyl)-alpha-rhamnoside (4) in addition to the known ellagic acid derivative, 4-O-methylellagic acid 3'-(2'',3''-di-O-acetyl)-alpha-rhamnoside (1). Their structures were elucidated on the basis of analysis of 1H NMR, 13C NMR, HMQC, HMBC and MS spectroscopic data. Compounds 1-4 were evaluated for their growth-inhibitory effect on Babesia gibsoni in vitro. Compounds 2 and 4 showed very weak activity, while compounds 1 and 3 showed moderate activity, with IC50 values of 28.5 and 52.1 microg/ml, respectively.


Assuntos
Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Babesia/efeitos dos fármacos , Elaeocarpaceae/química , Casca de Planta/química , Animais , Antiprotozoários/química , Ácido Elágico/análogos & derivados , Ácido Elágico/química , Ácido Elágico/isolamento & purificação , Ácido Elágico/farmacologia , Estrutura Molecular
15.
Leukemia ; 7(3): 441-5, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8383257

RESUMO

Four cDNA clones encoding myeloperoxidase were isolated from a cDNA library of monocytic leukemia SKM-1 cells. The sequences of two of them were identical to those of cDNA clones previously isolated from a HL-60 cell cDNA library. The sequences of the other two cDNA clones, MP-S34 and MP-S29, differed from those previously described. There was a deletion of 57 bp in the MP-S34 sequence, which was generated by partially skipping exon 9. MP-S29 had a 171 bp deletion, which was generated by completely skipping exon 10. Thus MP-S34 and MP-S29 encoded polypeptides lacking 19 and 57 amino acids, respectively. Both deletions were located on the sequence encoding the heavy subunit. These results indicate that the heterogeneity of the heavy subunit of MPO observed in leukocytes or leukemia could be in part produced by partial or complete skipping of an exon.


Assuntos
DNA de Neoplasias/genética , Leucemia Mieloide/enzimologia , Leucemia Mieloide/genética , Peroxidase/genética , Sequência de Aminoácidos , Sequência de Bases , Deleção Cromossômica , Clonagem Molecular , DNA de Neoplasias/isolamento & purificação , Éxons/genética , Genoma Humano , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta/genética , Splicing de RNA/genética , RNA Mensageiro/genética , Células Tumorais Cultivadas
16.
Hum Mutat ; 16(2): 177-8, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10923043

RESUMO

Mutations of myelin protein zero (MPZ) and connexin32 (Cx32) genes were examined in 70 unrelated Japanese patients with Charcot-Marie-Tooth disease (CMT) without PMP22 gene duplication. A new method, which could detect base pair mismatches with Rnase cleavage on agarose gel electrophoresis, identified 5 and 4 mutations of the MPZ and Cx32 genes, respectively, including one novel mutation (Ser128Ter) of Cx32. This non-isotopic RNase cleavage assay (NIRCA) employed in the present study is very suitable for exploring mutations of MPZ and Cx32 genes in a large number of CMT patients, as the phenotype of patients with CMT is greatly divergent from demyelinating to axonal pathology.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Conexinas/genética , Mutação/genética , Proteína P0 da Mielina/genética , Ribonucleases/metabolismo , Adolescente , Adulto , Pareamento Incorreto de Bases , Doença de Charcot-Marie-Tooth/enzimologia , Análise Mutacional de DNA/métodos , Feminino , Humanos , Hidrólise , Masculino , Pessoa de Meia-Idade , Proteína P0 da Mielina/metabolismo , Proteínas da Mielina/genética , Fenótipo , Ribonucleases/genética , Proteína beta-1 de Junções Comunicantes
17.
Endocrinology ; 126(2): 1009-13, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2298152

RESUMO

Although the posterior pituitary is known to contain the PRL releasing activity or factor (PRF), its chemical identification has been a matter of dispute. In the present study, we purified PRF in porcine posterior pituitary extracts to chemically determine the primary structure. PRF activity was assessed during purification by the release of immunoreactive PRL from superfused rat pituitary cells. Two hundred seventy porcine posterior pituitaries were boiled, homogenized, and extracted with 2 M acetic acid. The acid extract was precipitated with 67% acetone, and the supernatant was absorbed onto a C18 column. The column was eluted step-wise with 10, 20, 30, 40, 50, and 60% acetonitrile (CH3CN) in 0.1% trifluoroacetic acid (TFA). The greatest PRF activity was recovered in the 30% CH3CN/0.1% TFA fraction and was further purified by ion-exchange chromatography on SP-Sephadex, followed by gel-filtration on Sephadex G-50. The Sephadex G-50 fractions with major PRF activity were finally purified by two cycles of reverse phase HPLC, yielding a single peak of PRF. Amino acid, as well as sequence analyses, indicated that the highly purified PRF was oxytocin. Authentic oxytocin showed the same chromatographic behavior and biological activity as those of the isolated peptide. In another experiment, desalted crude extracts of rat and porcine posterior pituitary tissues were directly chromatographed by reverse phase HPLC, and each fraction was assayed for PRF activity. Only two areas showed PRF activity; the largest activity coeluted with oxytocin and the smaller one co-eluted with vasopressin. The fractions which coeluted with oxytocin also showed oxytocin immunoreactivity, as examined by RIA. The results clearly indicated that the major PRF in these posterior pituitary extracts was oxytocin.


Assuntos
Ocitocina/isolamento & purificação , Neuro-Hipófise/análise , Prolactina/metabolismo , Sequência de Aminoácidos , Animais , Bioensaio , Cromatografia Líquida de Alta Pressão , Feminino , Dados de Sequência Molecular , Ocitocina/farmacologia , Adeno-Hipófise/efeitos dos fármacos , Adeno-Hipófise/metabolismo , Ratos , Suínos
18.
FEBS Lett ; 383(3): 213-8, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8925898

RESUMO

A 45-bp proximal region of the rice glutelin promoter (-104/-60) containing two putative cis-elements, the AACA motif and GCN4 motifs, was fused to a truncated CaMV 35S promoter (-90/+9; -90 delta 35S)/GUS. The 45-bp fragment specifically enhanced the promoter activity in endosperm tissue of transformed tobacco. A substitution mutation of the GCN4 motif reduced the promoter activity, whereas mutation of the AACA motif increased the activity in the embryo as well as in the endosperm. These results suggest that the GCN4 motif generally enhances the promoter activity but that the combination of the two motifs confers the endosperm specificity. Furthermore, the function of the two motifs was dependent on the orientation and/or distance from a G-box element in -90 delta 35S, suggesting that synergistic interaction between the factors that recognize those motifs and the G-box element is important for transcriptional regulation.


Assuntos
Proteínas Fúngicas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Glutens/biossíntese , Oryza/metabolismo , Regiões Promotoras Genéticas , Proteínas Quinases/genética , Proteínas de Saccharomyces cerevisiae , Sequência de Bases , Proteínas de Ligação a DNA/genética , Glucuronidase/biossíntese , Glutens/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Oryza/genética , Folhas de Planta , Raízes de Plantas , Caules de Planta , Plantas Geneticamente Modificadas , Plantas Tóxicas , Proteínas Recombinantes/biossíntese , Sequências Reguladoras de Ácido Nucleico , Sementes/metabolismo , Nicotiana , Transcrição Gênica
19.
Clin Exp Metastasis ; 9(4): 363-75, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1831074

RESUMO

We investigated the adhesion of three morphologically distinct human neuroblastoma cell lines (NCG, GOTO and SK-N-DZ) to intact fibronectin, central cell binding domain fragment (CBF) and CS peptide-IgG conjugates in the fibronectin molecule. Each cell line was found to express different integrin fibronectin receptors (alpha 3 beta 1, alpha 4 beta 1 and alpha 5 beta 1), although similarly attached on intact fibronectin. To CBF, NCG attached well, while GOTO moderately and SK-N-DZ poorly attached. Only GOTO adhered to CS1-IgG. RGDS inhibited the spreading of NCG and SK-N-DZ on intact fibronectin, but it barely inhibited that of GOTO. The analysis by fluorescence-activated cell sorting (FACS) revealed that NCG expressed abundant alpha 3 beta 1 and alpha 5 beta 1, but little alpha 4 beta 1, while GOTO expressed a large amount of alpha 4 beta 1 as well as alpha 5 beta 1. SK-N-DZ was undetectable in any of these molecules, but expressed alpha v beta 1, which was identified by immunoprecipitation and immunoblotting. Polyclonal antibody to alpha v beta 3 inhibited the adhesion of SK-N-DZ but not that of NCG or GOTO on intact fibronectin. These results suggest the existence of a distinct mechanism of cell adhesion to fibronectin among human neuroblastoma cell lines. It remains to be determined if such heterogeneous adhesion properties are related to the unique metastatic character of human neuroblastoma.


Assuntos
Fibronectinas/fisiologia , Metástase Neoplásica , Neuroblastoma/patologia , Adesão Celular , Humanos , Neuroblastoma/química , Oligopeptídeos/farmacologia , Fragmentos de Peptídeos/fisiologia , Receptores de Fibronectina , Receptores Imunológicos/análise
20.
Neuroscience ; 129(1): 1-10, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15489023

RESUMO

In order to clarify the role of hippocampal N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors in different stages of spatial working memory, we first assessed the rats' performance in a delay-interposed eight-arm radial maze task (experiment 1). When a delay was interposed after the first four correct choices, rats showed more errors in the second-half performance depending on the length of delay; however, they did not show any significant increase of error choices until the delay was beyond 2 h. We then tested the effect of 2-amino-5-phosphonopentanoic acid (AP5), a competitive NMDA receptor antagonist, and 2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulfonamide (NBQX)-disodium, an AMPA receptor antagonist, on a standard (no delay-interposed) radial maze task (experiment 2). The drug effect was maintained 15-30 min but it completely disappeared 60 min after dorsal hippocampal microinjection. Based on these findings we finally investigated the effects of hippocampal AP5 and NBQX administered at different stages of 2 h delay-interposed radial maze task on the second-half performance (experiment 3). AP5 immediately before the first-half and before the second-half performance significantly impaired the correct choices, but the treatment immediately after the first-half performance did not, while NBQX impaired them in all three conditions. Results suggest that hippocampal NMDA receptors play an important role in encoding and retrieval processes of spatial working memory, while AMPA receptor activation is necessary not only in these processes but also in consolidation/retention process.


Assuntos
Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Hipocampo/fisiologia , Aprendizagem em Labirinto/fisiologia , Memória de Curto Prazo/fisiologia , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Injeções Intraventriculares , Masculino , Quinoxalinas/farmacologia , Ratos , Ratos Wistar , Receptores de AMPA/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA