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4.
Org Biomol Chem ; 14(14): 3501-5, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26988145

RESUMO

We examined the palladium-catalyzed allylic alkylation of trifluoromethyl group-substituted racemic and acyclic unsymmetrical 1,3-disubstituted allylic benzoate with a malonate anion, and succeeded in obtaining an enantiomerically enriched product in high yields with high ee values through the dynamic kinetic asymmetric transformation (DYKAT). The best result was attained by the [Pd(C3H5)(cod)]BF4/(S)-tol-BINAP in the presence of BSA or DMAP as a base.

5.
Org Lett ; 16(9): 2442-5, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24758353

RESUMO

The palladium-catalyzed regio- and enantioselective allylic amination of trifluoromethyl group substituted racemic and unsymmetrical 1,3-disubstituted allylic esters has been accomplished. The enantioselective formation of the α-type allylic amines was attained by the dynamic kinetic asymmetric transformation (DYKAT).

6.
J Biosci Bioeng ; 112(5): 462-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21839677

RESUMO

Methyl viologen (MV) causes severe oxidative stress by generating superoxide in the photosystem. The marine Chlamydomonas strain W80 is highly tolerant to MV (inhibitory concentration 50% [IC50]=110 µM), and another marine Chlamydomonas strain HS5 shows also relatively a high tolerance (IC50=12 µM). These two marine strains and a freshwater Chlamydomonas reinhardtii, which is highly sensitive to MV (IC50=0.03 µM), were compared with respect to their reactive oxygen species (ROS) eliminating enzymes (superoxide dismutase, catalase, glutathione peroxidase, and ascorbate peroxidase), intracellular free amino acids, and antioxidant activities of the cell extracts. The marked difference between the marine Chlamydomonas strains and C. reinhardtii is the much higher (more than 5 fold) ascorbate peroxidase (APX) activity in the marine strains. The marine strains also kept the high APX activities (more than 100% of non-stressed condition) under the MV stressed condition, while the APX activity in C. reinhardtii was significantly decreased (36% of non-stressed condition) under the stressed condition, indicating that APX activity potentially contributes to the oxidative stress tolerance in Chlamydomonas. In addition, the levels of intracellular free proline, which is supposed to ameliorate oxidative stress, were several tens of times higher in the marine Chlamydomonas strains than in C. reinhardtii.


Assuntos
Chlamydomonas reinhardtii/metabolismo , Chlamydomonas/metabolismo , Água Doce/microbiologia , Água do Mar/microbiologia , Animais , Ascorbato Peroxidases/metabolismo , Catalase/metabolismo , Chlamydomonas/classificação , Chlamydomonas/enzimologia , Chlamydomonas reinhardtii/enzimologia , Clorofila/metabolismo , Glutationa Peroxidase/metabolismo , Oxirredução , Estresse Oxidativo , Paraquat/farmacologia , Peroxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
7.
Mol Nutr Food Res ; 55(3): 467-75, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20938990

RESUMO

SCOPE: Glucose uptake in skeletal muscle is crucial for glucose homeostasis. METHODS AND RESULTS: Insulin and muscle contraction increase glucose uptake accompanied by the translocation of glucose transporter (GLUT) 4. In a search for promising foods, which can increase glucose uptake in skeletal muscle, we screened for active polyphenols by assaying for uptake of 2-deoxyglucose (2DG) in rat L6 muscle cells. Among 37 compounds, 4-hydroxyderricin and xanthoangelol, prenylated chalcones abundant in Ashitaba (Angelica keiskei Koidzumi, family Apiaceae), significantly increased 2DG uptake in L6 cells by 1.9-fold at 10 µM, compared with the level in DMSO-treated control cells. Next, we investigated the effect of these chalcones on the translocation of GLUT4 and its underlying mechanisms. The chalcones increased the GLUT4 level in the plasma membrane of L6 cells, but activated neither protein kinase C ζ/λ, Akt, nor adenosine monophosphate-activated protein kinase, all of which regulate the GLUT4 translocation. Interestingly, the oral administration of a titrated chalcone-enriched Ashitaba extract containing 150.6 mg/g (dry base) of 4-hydroxyderricin and 146.0 mg/g (dry base) of xanthoangelol suppressed acute hyperglycemia in oral glucose tolerance tests of mice. CONCLUSIONS: Ashitaba is a promising functional food for the maintenance of the blood glucose level by inducing skeletal muscle-associated glucose uptake.


Assuntos
Chalcona/análogos & derivados , Desoxiglucose/farmacocinética , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Prenilação , Angelica/química , Animais , Linhagem Celular , Chalcona/farmacologia , Flavonoides/análise , Flavonoides/farmacologia , Teste de Tolerância a Glucose , Hiperglicemia/dietoterapia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Musculares , Músculo Esquelético , Fenóis/análise , Fenóis/farmacologia , Polifenóis , Proteína Quinase C/metabolismo , Transporte Proteico , Distribuição Aleatória , Ratos
8.
J Biosci Bioeng ; 110(1): 99-101, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20541124

RESUMO

The removal of bisphenol A, an endocrine disruptor, by 25 different kinds of Salvia cultivars was examined with hydroculture experiments. All the Salvia cultivars showed a high BPA-eliminating ability, and 100% to 74% of BPA (50 muM) was eliminated after 3 days.


Assuntos
Biodegradação Ambiental , Fenóis/metabolismo , Salvia/metabolismo , Compostos Benzidrílicos , Disruptores Endócrinos/metabolismo , Proteínas de Schizosaccharomyces pombe/química , Fatores de Tempo
9.
J Biosci Bioeng ; 108(5): 365-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19804857

RESUMO

Comparative analysis was performed with a CFo ATP synthase subunit II homologue (CFo-II) derived from marine or fresh-water algae. The marine algae-derived CFo-II-transformed Escherichia coli grew and accumulated ATP more vigorously in NaCl or Cadmium containing medium, suggesting that this gene was useful for the development of stress-tolerant plant.


Assuntos
Trifosfato de Adenosina/metabolismo , Escherichia coli/metabolismo , Eucariotos/enzimologia , Água Doce/microbiologia , ATPases Translocadoras de Prótons/química , ATPases Translocadoras de Prótons/metabolismo , Água do Mar/microbiologia , Proliferação de Células , Clonagem Molecular , Escherichia coli/genética , Subunidades Proteicas , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
10.
J Biosci Bioeng ; 107(4): 352-4, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19332291

RESUMO

Here we report the isolation and characterization of the Chlamydomonas sp. W80-derived CFo ATP synthase subunit II WCFII homologue gene. Intracellular ATP concentration and stress-tolerance of Escherichia coli were increased by transformation with WCFII. We propose that WCFII-mediated stress tolerance is due to enhanced accumulation of intracellular ATP.


Assuntos
Complexos de ATP Sintetase/genética , Chlamydomonas/genética , Sequência de Aminoácidos , Animais , Chlamydomonas/efeitos dos fármacos , Dados de Sequência Molecular , Estresse Oxidativo , Paraquat/farmacologia , Subunidades Proteicas/genética , Proteínas de Protozoários/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
11.
J Biosci Bioeng ; 103(5): 420-6, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17609156

RESUMO

Portulaca oleracea, a garden plant prevalent from spring to autumn in Japan, showed the ability to efficiently remove from water bisphenol A (BPA), which is well known as an endocrine disrupting compound (EDC) having estrogenic properties. In water culture, 50 muM BPA was almost completely removed within 24 h when the ratio of whole plant weight to the water volume was set up at 1 g to 25 ml. The estrogenic activity of the water decreased in parallel with the elimination of BPA. This plant also rapidly removed other EDCs having a phenol group including octylphenol (OP), nonylphenol (NP), 2,4-dichlorophenol (2,4-DCP) and 17beta-estradiol and, thereby, removed the endocrine disrupting activities. In addition, the ability of P. oleracea to remove BPA was not affected by BPA concentration (up to 250 microM), by cultivation in the dark, by temperatures ranging from 15 degrees C to 30 degrees C, or by pH ranging from 4 to 7. Moreover, the ability of P. oleracea to individually remove BPA, NP, and OP was the same as when they were all present. These results suggest that P. oleracea is a promising material for practical phytoremediation of landfill leachates and industrial wastewater contaminated with the tested EDCs.


Assuntos
Disruptores Endócrinos/farmacocinética , Magnoliopsida/metabolismo , Fenóis/farmacocinética , Poluentes Químicos da Água/farmacocinética , Purificação da Água/métodos , Compostos Benzidrílicos , Biodegradação Ambiental , Disruptores Endócrinos/isolamento & purificação , Fenóis/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação
12.
FEMS Microbiol Lett ; 271(1): 48-52, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17391362

RESUMO

A novel gene with antistress activities against both salt (NaCl) and cadmium stresses was isolated from the cDNA library of halotolerant green alga Chlamydomonas sp. strain W80 by a functional expression screening with Escherichia coli. The C-terminal region of this protein is responsible for the antistress activity, because N-terminal truncated clone of this gene retains the antistress activity, and the C-terminal truncated clone loses the activity. In the C-terminal region, there is a histidine and aspartic acid-rich domain (HD-rich domain).


Assuntos
Adaptação Fisiológica/genética , Chlamydomonas/genética , Chlamydomonas/fisiologia , Resistência a Medicamentos/genética , Sequência de Aminoácidos , Animais , Cádmio/metabolismo , Cádmio/farmacologia , Chlamydomonas/efeitos dos fármacos , DNA de Algas/química , DNA de Algas/genética , DNA de Protozoário/química , DNA de Protozoário/genética , Escherichia coli/genética , Viabilidade Microbiana , Dados de Sequência Molecular , Análise de Sequência de DNA , Deleção de Sequência , Cloreto de Sódio/farmacologia , Microbiologia da Água
13.
FEMS Microbiol Lett ; 236(1): 41-5, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15212788

RESUMO

By a functional expression screening with cyanobacterial cells, a new member of group 3 late embryogenesis abundant protein genes (designated cw80lea3) was isolated from the cDNA library of halotolerant green alga Chlamydomonas sp. strain W80. The principle of the screening method was based on the acquisition of NaCl salt-tolerance of the fresh water cyanobacterial cells carrying the halotolerant algal gene. The expression of cw80lea3 gene in the C. W80 cells was induced by salt- and cold-stresses, but not by abscisic acid treatment.


Assuntos
Chlamydomonas/crescimento & desenvolvimento , Chlamydomonas/genética , Estresse Oxidativo/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Animais , Chlamydomonas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Sais/metabolismo , Temperatura
14.
Infect Control Hosp Epidemiol ; 25(2): 156-61, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14994942

RESUMO

OBJECTIVES: To investigate and control an outbreak of bloodstream infections (BSIs) caused by Serratia marcescens and to identify risk factors for respiratory colonization or infection with S. marcescens. DESIGN: Epidemiologic investigation, including review of medical and laboratory records, procedural investigations, pulsed-field gel electrophoresis (PFGE) typing of environmental and patient isolates, statistical study, and recommendation of control measures. PATIENTS AND SETTING: All patients admitted to a 380-bed, secondary-care hospital in Osaka Prefecture, Japan, from July 1999 through June 2000 (study period). RESULTS: Seventy-one patients were colonized or infected with S. marcescens; 3 patients who developed primary BSIs on the same ward within 5 days in June 2000 had isolates with indistinguishable PFGE patterns and indwelling intravenous catheters for more than 5 days. On multivariate analysis, among 36 case-patients with positive sputum specimens and 95 control-patients, being bedridden (odds ratio [OR], 15.91; 95% confidence interval [CI95], 4.17-60.77), receiving mechanical ventilation (OR, 7.86; CI95, 2.27-27.16), being older than 80 years (OR, 3.12; CI95, 1.05-9.27), and receiving oral cleaning care (OR, 3.10; CI95, 1-9.58) were significant risk factors. S. marcescens was isolated from the fluid tanks of three nebulizers and a liquid soap dispenser. The hospital did not have written infection control standards, and many infection control practices were found to be inadequate (eg, respiratory equipment was used without disinfection between patients). CONCLUSIONS: Poor hospital hygiene and the lack of standard infection control measures contributed to infections hospital-wide. Recommendations to the hospital included adoption of written infection control policies.


Assuntos
Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções por Serratia/epidemiologia , Serratia marcescens/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Infecção Hospitalar/microbiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Infecções por Serratia/microbiologia
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