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1.
J Phys Condens Matter ; 23(1): 015902, 2011 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21406829

RESUMO

The electronic structure of BiFeO3 (BFO), BiFeO3-PbTiO(3) solid solution (BFO-PT), and Mn-doped BFO-PT (BFM-PT) films fabricated by chemical solution deposition was investigated by x-ray absorption fine structure (XAFS). The BiFeO3 shows a large leakage current owing to the mixed valance state of Fe(2 +) and Fe(3 +). The BFO film has a blunt absorption edge jump indicating the charge fluctuated state of the iron ions. The BFO-PT and BFM-PT films have sharp absorption edges, and the absorption energy of these films shifted to opposite energy. The valence fluctuation of the iron ions was closely connected with the leakage current properties. The charge fluctuated BFO film showed a leaky feature, and the charge unfluctuated BFO-PT and BFM-PT films had improved leakage current properties. The valence fluctuation of the iron ions can be controlled by Mn substitution and by making solid solutions.

2.
Med Biol Eng Comput ; 43(6): 751-5, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16594302

RESUMO

A novel instrument for measurement of X-ray intensity from mammography consists of a sensitive pyro-electric detector, a high-sensitivity, low-noise current-to-voltage converter, a microcontroller and a digital display. The heart of this device, and what makes it unique is the pyro-electric detector, which measures radiation by converting heat from absorbed incident X-rays into an electric current. This current is then converted to a voltage and digitised. The detector consists of a ferro-electric crystal; two types were tested: lithium tantalate and lithium niobate. X-ray measurement in mammography is challenging because of its relatively low photon energy range, from 11 keV to 15 keV equivalent mean energy, corresponding to a peak tube potential from 22 to 36 kV. Consequently, energy fluence rate or intensity is low compared with that of common diagnostic X-ray. The instrument is capable of measuring intensities as low as 0.25 mW m(-2) with precision greater than 99%. Not only was the instrument capable of performing in the clinical environment, with high background electromagnetic interference and vibration, but its performance was not degraded after being subjected to 140 roentgen (3.6 x 10(-2) C kg(-2) air) as measured by piezo-electric (d33) or pyro-electric coefficients.


Assuntos
Mamografia , Radiometria/instrumentação , Desenho de Equipamento , Feminino , Humanos , Modelos Teóricos , Tecnologia Radiológica/instrumentação
3.
Biochemistry (Mosc) ; 69(1): 70-4, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14972021

RESUMO

Since little is known about how coffee intake affects low-density lipoprotein (LDL) oxidative susceptibility and serum lipid levels, we conducted an in vivo study in 11 healthy male students of Wakayama Medical University aged between 20 and 31 years fed an average Japanese diet. On days 1-7 of the study, the subjects drank mineral water. On day 7, the subjects began drinking coffee, 24 g total per day, for one week. This was followed by a one week "washout period" during which mineral water was consumed. Fasting peripheral venous blood samples were taken at the end of each one-week period. LDL oxidation lag time was approximately 8% greater (p < 0.01) after the coffee drinking period than the other periods. Serum levels of total cholesterol and LDL-cholesterol (LDL-C) and malondialdehyde (MDA) as thiobarbituric acid reactive substances (TBARS) were significantly decreased after the coffee drinking period. Finally, regular coffee ingestion may favorably affect cardiovascular risk status by modestly reducing LDL oxidation susceptibility and decreasing LDL-cholesterol and MDA levels.


Assuntos
Cafeína/administração & dosagem , Cafeína/farmacologia , Café , Lipídeos/sangue , Lipoproteínas LDL/metabolismo , Adulto , Cafeína/sangue , Ácido Clorogênico/sangue , Ácido Clorogênico/urina , Humanos , Lipoproteínas LDL/sangue , Masculino , Oxirredução/efeitos dos fármacos
4.
Plant Cell Physiol ; 42(9): 982-91, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11577193

RESUMO

The Purple leaf (Pl) locus of rice (Oryza sativa L.) affects regulation of anthocyanin biosynthesis in various plant tissues. The tissue-specific patterns of anthocyanin pigmentation, together with the syntenic relationship, indicate that the rice Pl locus may play a role in the anthocyanin pathway similar to the maize R/B loci. We isolated two cDNAs showing significant identity to the basic helix-loop-helix (bHLH) proteins found in the maize R gene family. OSB1 appeared to be allelic to the previously isolated R homologue, Ra1, but showed a striking difference at the C-terminus because of a 2-bp deletion. Characterization of the corresponding genomic region revealed that the sequence identical to a 5'-portion of OSB2 existed approximately 10-kb downstream of the OSB1 coding region. OSB2 lacks a conserved C-terminal domain. Restriction fragment length polymorphism analyses using an F(2) population indicate that both genes co-segregate with the purple leaf phenotype. A transient complementation assay showed that the anthocyanin pathway is inducible by OSB1 or OSB2. These results suggest that the Pl(w) allele may be complex and composed of at least two genes encoding bHLH proteins.


Assuntos
Antocianinas/biossíntese , Proteínas de Ligação a DNA/genética , Sequências Hélice-Alça-Hélice/genética , Oryza/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Alelos , Sequência de Aminoácidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Clonagem Molecular , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Oryza/metabolismo , Fenótipo , Proteínas de Plantas/metabolismo , Mapeamento por Restrição , Sementes/genética , Sementes/metabolismo , Alinhamento de Sequência , Fatores de Transcrição/metabolismo
5.
Genes Cells ; 6(4): 327-36, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11318875

RESUMO

BACKGROUND: The TERMINAL FLOWER 1 (TFL1) gene of Arabidopsis plays an important role in regulating flowering time and in maintaining the fate of inflorescence meristem (IM). TFL1 is a homologue of CENTRORADIALIS (CEN) from Antirrhinum, which is only involved in IM maintenance. Recent mutational studies and the genome project revealed that TFL1 belongs to a small gene family in Arabidopsis, in which functional divergence may have occurred among the members. RESULTS: We found a new member of the TFL1 gene family, which is mapped on chromosome 2 of Arabidopsis. The predicted protein sequence encoded by this gene is more closely related to that of CEN than other Arabidopsis TFL1 homologues (and therefore named ATC for Arabidopsis thaliana CENTRORADIALIS homologue). Transgenic plants constitutively expressing the ATC gene (35S:ATC), in either wild-type or tfl1 mutant backgrounds, showed a phenotype similar to that observed in transgenic plants constitutively expressing the TFL1 gene. However, in contrast to TFL1, the expression of ATC was only detected in the hypocotyl of young plants, and not in the IM. In addition, an atc loss-of-function mutant, isolated by screening a T-DNA library, showed no phenotypes that were similar to those of tfl1 mutants. CONCLUSION: The phenotypes of transgenic plants over-expressing ATC suggest that the ATC protein can functionally substitute for TFL1. However, the pattern and level of expression and the loss-of-function phenotype indicate that ATC does not participate in the regulation of IM identity, but rather has a role that is different from that of TFL1.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/genética , Genes de Plantas , Sequência de Aminoácidos , Clonagem Molecular , Primers do DNA/química , DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas , Hibridização In Situ , Dados de Sequência Molecular , Mutagênese Insercional , Mutação , Fenótipo , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Homologia de Sequência de Aminoácidos
6.
Bone ; 28(3): 332-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11248666

RESUMO

The effects of coffee on bone metabolism are still controversial, although several studies have suggested that caffeine and/or heavy coffee consumption is associated with a significant increase in risk of fracture, osteoporosis, and periodontal disease. Therefore, we sought to clarify the relationship between coffee consumption and bone metabolism using male Wistar rats. Forty-eight male Wistar rats were assigned to three treatment groups including a control-diet group (control, n = 16, coffee-free diet), a 0.62% coffee-diet group (low caffeine, n = 16, diet supplemented with 6.2 g/kg of the control diet), and a 1.36% coffee-diet group (high caffeine, n = 16, diet supplemented with 13.6 g/kg of the control diet), and animals were maintained on an experimental diet for 140 days. Although caffeine in serum was not detected in rats fed the control diet, low-intake coffee for 140 days led to an increase in caffeine concentration to 0.53 +/- 0.11 microg/mL and high-intake coffee led to an increase of 1.77 +/- 0.22 microg/mL. No significant differences in body weight change, serum and urinary biochemical markers of bone metabolism, and bone histomorphometry were found between the coffee-diet groups and the control-diet group, except that urinary phosphorus excretion after 140 days of both coffee diets was significantly increased compared with controls (p < 0.05). In addition, the coffee diets were not associated with differences in tumor necrosis factor-alpha and interleukin-6, which have been implicated in the pathogenesis of bone loss together with interleukin-1beta. In conclusion, the present study strongly indicates that coffee does not stimulate bone loss in rats.


Assuntos
Osso e Ossos/metabolismo , Café , Aminoácidos/urina , Animais , Peso Corporal , Remodelação Óssea , Cafeína/sangue , Cálcio/urina , Interleucina-6/biossíntese , Interleucina-6/sangue , Masculino , Osteocalcina/sangue , Fósforo/urina , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo
7.
J Exp Biol ; 203(Pt 19): 2967-75, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10976033

RESUMO

Time-series data of swimming speed and dive depth were recorded in six female loggerhead turtles Caretta caretta during the internesting period. The dive profiles of all animals indicated that they stayed at particular depths without swimming and that these depths were correlated with dive duration. These results support the hypothesis that lung air is used to achieve neutral buoyancy in the loggerhead turtle. To test this hypothesis, female turtles were equipped with lead weights and time/depth recorders. The residence depth of the turtles increased when their specific gravity was artificially decreased. This indicates that they control depth rather than lung volume, suggesting that the residence depth of loggerhead turtles during the internesting period is not determined actively. They presumably remain at a particular depth exclusively to save energy for egg maturation during the internesting period. Lung volume was estimated from the change in depth of weighted animals to be 50-150 ml kg(-1). The resulting residence depth of all turtles was within the range at which they maintained the neutral buoyancy.


Assuntos
Tartarugas/fisiologia , Ar , Animais , Mergulho/fisiologia , Feminino , Pulmão/fisiologia , Modelos Biológicos , Água do Mar , Natação/fisiologia
8.
J Nutr Sci Vitaminol (Tokyo) ; 46(6): 316-20, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11227804

RESUMO

To clarify the relationship between coffee and fitness, we investigated the effect of coffee on weight gain and total cholesterol as well as production of cytokines and activities of GOT (aspartate aminotransferase; EC 2.6.1.1.) and GPT (alanine aminotransferase; EC 2.6.1.2.) as injected lipopolysaccharides. Forty-eight male Wistar rats were divided into three dietary groups (n=16), which were fed a stock diet (control group), the diet supplemented with freeze-dried coffee of 6.2 g/kg (0.62% coffee group), and the diet supplemented with freeze-dried coffee of 13.6 g/kg (1.36% coffee group). It was confirmed by HPLC analysis that the serum caffeine concentrations in both coffee groups became significantly higher in 140 days after the start of feeding. No significant differences in body weight and serum cholesterol were found between the coffee groups and control group, though the coffee groups tended to be somewhat high at cholesterol level. Activities of serum GOT and GPT increased at 2 h after LPS injection, but in the coffee groups were significantly suppressed (p<0.05). However, the coffee feeding could not suppress the increases of serum cytokine (TNF-alpha and IL-6) levels. These results suggest that coffee may serve as a preventive against liver injury.


Assuntos
Café , Lipopolissacarídeos/toxicidade , Fígado/efeitos dos fármacos , Aptidão Física , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Cafeína/sangue , Colesterol/sangue , Cromatografia Líquida de Alta Pressão , Café/efeitos adversos , Café/metabolismo , Citocinas/sangue , Dieta , Leptina/sangue , Lipopolissacarídeos/administração & dosagem , Fígado/enzimologia , Fígado/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Fatores de Tempo , Aumento de Peso/efeitos dos fármacos
9.
Plant Cell Physiol ; 41(12): 1334-46, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11134419

RESUMO

Variegated leaves are often caused by a nuclear recessive mutation in higher plants. Characterization of the gene responsible for variegation has shown to provide several pathways involved in plastid differentiation. Here we describe an Arabidopsis variegated mutant isolated by T-DNA tagging. The mutant displayed green and yellow sectors in all green tissues except for cotyledons. Cells in the yellow sector of the mutant contained both normal-appearing and mutant chloroplasts. The isolated mutant was shown to be an allele of the previously reported mutant, yellow variegated (var2). Cloning and molecular characterization of the VAR2 locus revealed that it potentially encodes a chloroplastic homologue of FtsH, an ATP-dependent metalloprotease that belongs to a large protein family involved in various cellular functions. ftsH-like genes appear to comprise a small gene family in Arabidopsis genome, since at least six homologues were found in addition to VAR2. Dispensability of VAR2 was therefore explained by the redundancy of genes coding for FstHs. In the yellow regions of the mutant leaves, accumulation of photosynthetic protein components in the thylakoid membrane appeared to be impaired. Based on the role of FtsH in a protein degradation pathway in plastids, we propose a possibility that VAR2 is required for plastid differentiation by avoiding partial photooxidation of developing chloroplasts.


Assuntos
Adenosina Trifosfatases/genética , Arabidopsis/genética , Proteínas de Bactérias/genética , Genes de Plantas , Proteínas de Membrana/genética , Serina Endopeptidases/genética , Proteases Dependentes de ATP , Adenosina Trifosfatases/química , Alelos , Sequência de Aminoácidos , Arabidopsis/enzimologia , Proteínas de Arabidopsis , Sequência de Bases , Cloroplastos/genética , Primers do DNA , Ligação Genética , Proteínas de Membrana/química , Microscopia Eletrônica , Dados de Sequência Molecular , Fenótipo , Filogenia , Plastídeos/ultraestrutura , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos , Serina Endopeptidases/química
10.
Plant Cell Physiol ; 41(10): 1157-63, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11148275

RESUMO

Components of some protein complexes present in the inner membrane of mitochondria are encoded in both nuclear and mitochondrial genomes, and correct sorting and assembly of these proteins is necessary for proper respiratory function. Recent studies in yeast suggest that Oxa1p, a protein conserved between prokaryotes and eukaryotes, is an essential factor for protein sorting and assembly into membranes. We previously identified AtOXA1, an Arabidopsis homologue of OXA1 by functional complementation of a yeast oxa1- mutant. In this study, we investigated the genomic organization of AtOXA1 and localization of the AtOXA1 protein. Characterization of the AtOXA1 genomic region indicated that the gene consists of 10 exons and is located on chromosome V. A database search also revealed another gene coding for a putative protein homologous to AtOXA1 on chromosome II. Transient expression of a green fluorescent protein (GFP) fusion in suspension-cultured tobacco cells showed that AtOXA1 is targeted into mitochondria by its N-terminal presequence. Antibodies raised against AtOXA1 recognized a 38-kDa intrinsic protein of the inner mitochondrial membrane. Thus, localization of AtOXA1 in the mitochondrial inner membrane, together with our previous complementation experiment in yeast, suggested that it is a functional homologue of Oxa1p.


Assuntos
Arabidopsis/metabolismo , Mitocôndrias/metabolismo , Proteínas Nucleares/metabolismo , Arabidopsis/genética , Sequência de Bases , Primers do DNA , Complexo IV da Cadeia de Transporte de Elétrons , Escherichia coli/genética , Membranas Intracelulares/metabolismo , Proteínas Mitocondriais , Dados de Sequência Molecular , Proteínas Nucleares/genética , Reação em Cadeia da Polimerase , Partículas Submitocôndricas/metabolismo
11.
Biofactors ; 10(2-3): 139-43, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10609875

RESUMO

Macrophage migration inhibitory factor (MIF), a putative cytokine involved in inflammatory and immune responses, was identified in rat peritoneal macrophages by Western blot analysis and its secretion into culture medium by enzyme-linked immunosorbent assay. To clarify the possibility of vitamin E as an immune modulator, we investigated the effect of vitamin E on MIF production in macrophages in response to calcium ionophore A23187 and lipopolysaccharide (LPS). Intraperitoneal injections of vitamin E (5 mg per rat) for 6 successive days resulted in a significant increase of alpha-tocopherol content in peritoneal macrophages. Alpha-tocopherol content of macrophages in vitamin E-treated rats was 478.3 +/- 90.7 ng/10(6) cells, whereas in control rats it was 1.5 +/- 0.5 ng/10(6) cells. For the control macrophages, total MIF content of the medium (2.5 x 10(6) cells/18 ml) without stimulation was 40.7 +/- 3.6 ng after 14 h culture, whereas stimulation with calcium ionophore A23187 (400 nM) and LPS (5.0 microg/ml) induced the elevation of MIF content to 65.9 +/- 7.5 ng and 74.3 +/- 10.4 ng, respectively (p < 0.05, n = 3). On the other hand, vitamin E-enriched macrophages without stimulation showed less MIF content (14.0 +/- 4.2 ng) than the control (p < 0.05, n = 3). Similarly, the increase of MIF of vitamin E-treated macrophages was significantly suppressed after stimulation with calcium ionophore A23187 or LPS, compared with the control macrophages (p < 0.01, n = 3). From analysis of intracellular MIF content by Western blot, we found no alteration of intracellular MIF content of vitamin E-macrophages, in contrast to the decreased content of control stimulated-macrophages, showing that vitamin E suppressed MIF secretion into the culture medium. Taken together, these results indicate that vitamin E may contribute to the regulation of inflammatory and immune responses through regulation of MIF secretion, possibly by modulating macrophage-membrane architecture.


Assuntos
Fatores Inibidores da Migração de Macrófagos/biossíntese , Macrófagos Peritoneais/efeitos dos fármacos , Vitamina E/farmacologia , Animais , Calcimicina/farmacologia , Tamanho Celular , Sobrevivência Celular , Células Cultivadas , Cinética , Lipopolissacarídeos/farmacologia , Fatores Inibidores da Migração de Macrófagos/metabolismo , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/metabolismo , Masculino , Ratos , Ratos Wistar
12.
Immunopharmacology ; 45(1-3): 159-62, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10615006

RESUMO

To clarify the pathogenic role of proteinases from Porphyromonas gingivalis, a 45 kDa proteinase was isolated from P. gingivalis culture medium by a combination of gel filtration (Bio-Gel A-0.5 m) and ion-exchange chromatographies (DEAE-Sephacel and SP-Sepharose FF). The enzyme was found to have a molecular mass of 45 kDa by SDS-PAGE and to require mercaptoethanol for its activation. The 45 kDa proteinase cleaved T-kininogen into small fragments, but failed to release kinin. In contrast, T-kininogen inhibited the Arg-amidolytic activity of the 45 kDa proteinase with a Ki of 2 nM. On the other hand, the 45 kDa proteinase did not stimulate the production of PGE2, IL-1beta, and TNF-alpha from the macrophages.


Assuntos
Endopeptidases/isolamento & purificação , Cininogênios/isolamento & purificação , Porphyromonas gingivalis/enzimologia , Proteínas de Bactérias/isolamento & purificação , Dinoprostona/metabolismo , Peso Molecular
13.
Kidney Int Suppl ; 71: S171-3, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10412768

RESUMO

BACKGROUND: Oxidized LDL increases the production of both prostaglandin E2 (PGE2) and thromboxane B2 (TXB2) in rat mesangial cells. These increases were suppressed by antioxidants such as alpha-tocopherol (alpha-Toc) or probucol. METHODS: We investigated the mechanism by which oxidized LDL leads to an increase in PGE2 production using rat mesangial cells in culture. We also examined how alpha-Toc supresses this augmentation, by measuring intracellular Ca2- and phospholipase A2 (PLA2) activity. RESULTS: In rat mesangial cells, oxidized LDL increased PLA2 activity by increasing the intracellular calcium ion content, which resulted in the induction of PGE2 production. On the other hand, pretreatment of cells with alpha-Toc, which resulted in a large uptake of alpha-Toc in cell membranes, markedly suppressed the augmentation of PGE2 production and PLA2 activity by oxidized LDL in a dose dependent manner. However, cytosolic PLA2 partially purified from mesangial cells was not inhibited by alpha-Toc despite an increase of alpha-Toc. CONCLUSION: These results suggest that the augmentation of PLA2 activity in mesangial cells by oxidized LDL in a result of oxidative stresses, and that the antioxidant action of alpha-Toc is responsible for the suppression of augmentation of PLA2 activity observed in mesangial cells exposed to oxidized LDL.


Assuntos
Mesângio Glomerular/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Fosfolipases A/efeitos dos fármacos , Vitamina E/farmacologia , Animais , Cálcio/metabolismo , Dinoprostona/biossíntese , Mesângio Glomerular/citologia , Mesângio Glomerular/enzimologia , Fosfolipases A/metabolismo , Fosfolipases A2 , Ratos
14.
Semin Thromb Hemost ; 25(6): 557-62, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10632478

RESUMO

Administration of lipopolysaccharide (LPS) induces inflammation and tissue injuries that occasionally results in disseminated intravascular coagulation (DIC). This process is believed to be mediated by vasoactive molecules such as kinins and leads to endothelial damage and obstruction of the microcirculation. In this study, we evaluated the involvement of T-kininogen and macrophage migration inhibitory factor (MIF) in endotoxin-induced systemic inflammation. T-Kininogen is a protein unique to the rat and known as an acute-phase protein in response to endotoxins. Similarly, MIF functions as a proinflammatory cytokine and glucocorticoid-induced immunoregulator. First, we examined the effects of anti-MIF antibody on Wistar King male rats (ca 400 g) treated with intraperitoneal injection of LPS. At 6 hours after LPS injection (5 mg/kg), the platelet counts had decreased from 85 +/- 12.8 (x 10(4)/microL) to 8.8 +/- 2.6 (x 10(4)/microL). We treated these rats with the anti-rat MIF antibody (5 mg gamma G immunoglobulin [IgG] fraction/kg) 2 hours prior to LPS injection. This treatment prevented the decrease in platelet counts (45.6 +/- 5.6 [x 10(4)/microL]). Next, we examined the potential of MIF for production of T-kininogen. Intraperitoneal injection of rat MIF significantly upregulated the serum content of T-kininogen at the dose of 500 microg MIF/head. These results imply that MIF and T-kininogen might function in concert in the event of endotoxin-induced inflammation.


Assuntos
Cininogênios/biossíntese , Fatores Inibidores da Migração de Macrófagos/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Anticorpos/farmacologia , Cininogênios/sangue , Cininogênios/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Fatores Inibidores da Migração de Macrófagos/imunologia , Masculino , Contagem de Plaquetas/efeitos dos fármacos , Ratos , Ratos Wistar , Fatores de Tempo , Fator de Necrose Tumoral alfa/efeitos dos fármacos
15.
Osaka City Med J ; 45(2): 175-90, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10730083

RESUMO

The survival rate of 92 patients with primary bladder cancer who had undergone total cystectomy during a 13-year period from 1984 to 1996 was examined. The mean follow-up period was 1,886 days. The 5-year survival rate was 67.9% and the 10-year survival rate was 55.1%. When survival rates were compared pathohistologically, with 81 patients with transitional cell carcinoma divided into two groups, a high-stage group including T3 and T4 patients and a low-stage group with all other patients, the cancer-specific 5-year survival rate of the low-stage group was 88.9% while that of the high-stage group was 45.4%; this difference was significant (p = 0.0002). There were also significant differences in survival rate between those with and those without regional lymph node metastasis, those with and those without lymphatic infiltration, and those with and those without vascular infiltration. However, there was no significant difference in survival rate for the 34 patients with T3 or T4 disease when those with or without chemotherapy and/or radiation therapy were compared.


Assuntos
Carcinoma de Células de Transição/cirurgia , Cistectomia , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Carcinoma de Células de Transição/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Análise de Sobrevida , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologia
16.
Plant Cell Physiol ; 40(12): 1287-96, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10682349

RESUMO

A cDNA clone, 4B-1, previously isolated by differential screening is preferentially expressed in floral organs of Arabidopsis thaliana. Characterization of the full length cDNA and the genetic locus corresponding to 4B-1 cDNA revealed that it potentially encodes a myrosinase binding protein (MBP) which is presumably present in a large myrosinase complex. The deduced amino acid sequence of the polypeptide encoded by cDNA clone (designated f-AtMBP) appeared to consist of two parts: one region at the C-terminal half representing overall homology with AtMBP, an MBP homologue in A. thaliana, and the other at an extended N-terminal region of about 150 amino acids showing significant identity with the N-terminal region of the MBP-related protein reported in Brassica. Expression analysis by RNA blot and in situ hybridization showed that f-AtMBP was specifically expressed in floral meristems, pistils, stamens, petals, and ovules of immature flowers, but no expression was observed in the specialized cells called the myrosin cells in the hypocotyl and cotyledons of developing seeds where myrosinase enzymes are normally found. Although MBPs and MBP-related proteins are considered to be inducible by exogenous application of signal molecules and physical wounding, we found that f-AtMBP expression was not activated by such treatment, suggesting that f-AtMBP is a novel type of MBP specific to floral organs.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Transporte/genética , Genes de Plantas , Glicoproteínas/genética , Glicosídeo Hidrolases/metabolismo , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Brassica/genética , Mapeamento Cromossômico , Primers do DNA/genética , DNA Complementar/genética , DNA de Plantas/genética , Expressão Gênica , Hibridização in Situ Fluorescente , Peptídeos e Proteínas de Sinalização Intracelular , Dados de Sequência Molecular , Filogenia , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
17.
Gene ; 221(1): 117-25, 1998 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-9852956

RESUMO

The yeast Abc1 protein acts as a chaperone-like protein essential for the proper conformation and efficient functioning of the respiratory complex III. By functional complementation of a yeast abc1 mutant, we have identified an Arabidopsis thaliana cDNA that corresponds to a single copy gene and encodes a protein sharing 45% similarity with the yeast Abc1p protein. Cytochrome spectra and respiratory activity measurements have shown that the plant protein allows a partial restoration of the complex III activity. No major difference in the steady-state level of ABC1At mRNA was observed in various plant tissues, suggesting that ABC1At is constitutively expressed in A. thaliana. Phylogenetic analysis revealed that the Abc1At protein belongs to a large family of proteins composed of two eukaryotic and one prokaryotic subgroups differing by their degree of similarity and probably by their function.


Assuntos
Arabidopsis/genética , DNA Complementar/isolamento & purificação , Complexo III da Cadeia de Transporte de Elétrons/genética , Proteínas Fúngicas/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , DNA Complementar/genética , Deleção de Genes , Dosagem de Genes , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Dados de Sequência Molecular , Mutação , Filogenia , Proteínas de Plantas/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
18.
Plant Mol Biol ; 38(4): 565-76, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9747802

RESUMO

We have previously identified two cDNAs encoding vegetative storage proteins (VSPs) in Arabidopsis thaliana. Unlike soybean in which VSPs accumulate at high levels in leaves, A. thaliana VSP mRNAs are abundant in flowers. To understand tissue-specific expression and possible roles of VSPs on reproductive organ development, genes corresponding to VSPs (Vsp1 and Vsp2) and their putative promoters were characterized in this study. Genomic sequence analysis revealed that Vsp1 and Vsp2 resemble each other except in their introns, and that these two genes were organized in a tandem array with an interval of 6 kb in a region. The expression patterns of Vsp1 and Vsp2 were examined using transgenic A. thaliana plants carrying a promoter from Vsp1 or Vsp2 fused to a bacterial beta-glucuronidase (GUS) reporter gene. The promoter from Vsp1 expressed its effect in gynoecia, especially in styles, the basal and distal ends of ovaries and in siliques, whereas the promoter from Vsp2 showed its activity in vegetative shoots, petioles, peduncles and receptacles of floral organs. These results suggest that expression of Vsp1 and Vsp2 may be developmentally regulated in A. thaliana. In the transgenic plants, the GUS activity was induced by wounding in an area around the mid-rib of leaves. Therefore, Vsp1 and Vsp2 promoters appear to have elements required for both tissue specificity and wounding.


Assuntos
Arabidopsis/genética , Genes de Plantas , Proteínas de Plantas/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Sequência de Bases , Mapeamento Cromossômico , Primers do DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes Reporter , Glucuronidase/genética , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Homologia de Sequência do Ácido Nucleico , Distribuição Tecidual
19.
Proc Natl Acad Sci U S A ; 95(18): 11014-9, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9724821

RESUMO

One-fifth of the tRNAs used in plant mitochondrial translation is coded for by chloroplast-derived tRNA genes. To understand how aminoacyl-tRNA synthetases have adapted to the presence of these tRNAs in mitochondria, we have cloned an Arabidopsis thaliana cDNA coding for a methionyl-tRNA synthetase. This enzyme was chosen because chloroplast-like elongator tRNAMet genes have been described in several plant species, including A. thaliana. We demonstrate here that the isolated cDNA codes for both the chloroplastic and the mitochondrial methionyl-tRNA synthetase (MetRS). The protein is transported into isolated chloroplasts and mitochondria and is processed to its mature form in both organelles. Transient expression assays using the green fluorescent protein demonstrated that the N-terminal region of the MetRS is sufficient to address the protein to both chloroplasts and mitochondria. Moreover, characterization of MetRS activities from mitochondria and chloroplasts of pea showed that only one MetRS activity exists in each organelle and that both are indistinguishable by their behavior on ion exchange and hydrophobic chromatographies. The high degree of sequence similarity between A. thaliana and Synechocystis MetRS strongly suggests that the A. thaliana MetRS gene described here is of chloroplast origin.


Assuntos
Arabidopsis/genética , Cloroplastos/enzimologia , Metionina tRNA Ligase/genética , Mitocôndrias/enzimologia , Sequência de Aminoácidos , Arabidopsis/enzimologia , Sequência de Bases , Transporte Biológico , DNA Complementar , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Metionina tRNA Ligase/isolamento & purificação , Metionina tRNA Ligase/metabolismo , Dados de Sequência Molecular
20.
Biochim Biophys Acta ; 1404(3): 427-34, 1998 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-9739171

RESUMO

Macrophage migration inhibitory factor (MIF) was identified in rat peritoneal macrophages by Western blot analysis and its secretion into culture medium by enzyme-linked immunosorbent assay. We investigated the effect of vitamin E on MIF production in macrophages in response to phorbol 12-myristate-13-acetate (PMA), calcium ionophore A23187, and lipopolysaccharide (LPS). Intraperitoneal injections of vitamin E (5 mg per rat) for 6 successive days resulted in a significant increase of alpha-tocopherol content in peritoneal macrophages (478.3+/-90.7 ng/106 cells) compared with the control (1.5+/-0.5 ng/10(6) cells). For the control macrophages, MIF content of the medium (2.5x10(6) cells/18 ml) without stimulation was 2.27+/-0.20 ng/ml after 14 h culture, whereas stimulation with calcium ionophore A23187 (400 nM) and LPS (5.0 microg/ml) induced the elevation of MIF content to 3. 66+/-0.41 and 4.12+/-0.58 ng/ml, respectively. On the other hand, vitamin E-enriched macrophages without stimulation showed less MIF content (0.77+/-0.23 ng/ml) than the control. Similarly, the increase of MIF of vitamin E-treated macrophages was significantly suppressed after stimulation with calcium ionophore A23187 or LPS, compared with the control macrophages. From analysis of intracellular MIF content by Western blot, we found no alteration of intracellular MIF content of vitamin E-macrophages, in contrast to the decreased content of control stimulated-macrophages. Taken together, these results indicate that vitamin E may contribute to the regulation of immune responses through regulation of MIF secretion.


Assuntos
Fatores Inibidores da Migração de Macrófagos/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Vitamina E/farmacologia , Animais , Calcimicina , Meios de Cultura/análise , Interleucina-6/análise , Lipopolissacarídeos , Macrófagos Peritoneais/metabolismo , Masculino , Ratos , Ratos Wistar , Acetato de Tetradecanoilforbol , Fator de Necrose Tumoral alfa/análise
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