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1.
Ophthalmol Retina ; 5(9): 910-917, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33309963

RESUMO

PURPOSE: To survey the prevalence and clinical and genetic characteristics of pachydrusen in eyes with central serous chorioretinopathy (CSC) and those of Japanese individuals in the general population. DESIGN: Prospective, observational cohort study. PARTICIPANTS: One thousand thirty-seven Japanese patients were included in this study. Three hundred seven patients (614 eyes) had treatment-naïve CSC without choroidal neovascularization in either eye, whereas 730 individuals (1640 eyes) were Japanese individuals from the general population without explicit ocular diseases. METHODS: Pachydrusen were detected using color fundus photography, and subfoveal choroidal thickness was measured using OCT. Genotypic distributions of 3 single nucleotide polymorphisms, ARMS2 A69S, CFH I62V, and CFH Y402H, were evaluated. MAIN OUTCOME MEASURES: Prevalence of pachydrusen and association with choroidal thickness. RESULTS: The prevalence of pachydrusen was significantly higher among CSC patients than among the general population group (40.1% vs. 15.6%; P < 0.001). Individuals with pachydrusen in either group were significantly older than those without pachydrusen (CSC patients: 62.1 years vs. 48.8 years [P < 0.001]; general individuals: 70.3 years vs. 51.9 years [P < 0.001]). No significant difference was found in subfoveal choroidal thickness between those with and without pachydrusen (CSC patients: 370 µm vs. 375 µm; [P = 0.574]; general population: 297 µm vs. 303 µm [P = 0.521]). However, after adjusting for age, gender, and refractive error, subfoveal choroidal thickness was notably thicker in individuals with pachydrusen than that in individuals without pachydrusen in both groups (P = 0.003 and P = 0.013, respectively). No significant difference was found in genotype distributions between CSC patients with pachydrusen and those without it; whereas, the T allele frequency of ARMS2 A69S was higher in general population individuals with pachydrusen than that in general population individuals without pachydrusen (42.2% vs. 33.9%; P < 0.001; OR, 1.86, adjusted for age, gender, and choroidal thickness). CONCLUSIONS: Pachydrusen was observed more frequently in CSC patients compared with individuals from the general population. In both groups, pachydrusen was associated with a thicker choroid, suggesting that pachydrusen should be considered as a significant sign of pachychoroid.


Assuntos
Coriorretinopatia Serosa Central/genética , Proteínas do Olho/genética , Polimorfismo de Nucleotídeo Único , Retina/diagnóstico por imagem , Drusas Retinianas/genética , Idoso , Coriorretinopatia Serosa Central/complicações , Coriorretinopatia Serosa Central/epidemiologia , DNA/genética , Feminino , Seguimentos , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Drusas Retinianas/complicações , Drusas Retinianas/epidemiologia , Tomografia de Coerência Óptica/métodos
2.
FEMS Microbiol Lett ; 213(1): 13-20, 2002 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-12127482

RESUMO

A new lysyl endopeptidase producing strain, Lysobacter sp. IB-9374, was isolated from soil. This strain secreted the endopeptidase to culture medium at 6-12-fold higher levels relative to Achromobacter lyticus and Lysobacter enzymogenes. The mature Lysobacter sp. enzyme was enzymatically identical to Achromobacter lysyl endopeptidase bearing lysyl bond specificity, a high peptidase activity, a wide pH optimum, and stability against denaturants. Nucleotide sequence analysis of the Lysobacter sp. lysyl endopeptidase gene revealed that the enzyme is synthesized as a precursor protein consisting of signal peptide (20 amino acids (aa)), pro-peptide (185 aa), mature enzyme (268 aa), and C-terminal extension peptide (198 aa). The deduced amino acid sequence of the mature enzyme was totally identical to that of the Achromobacter enzyme. The Lysobacter sp. precursor protein has an 18-aa longer peptide chain following nine consecutive amino acid residues distinct from the Achromobacter counterpart at the C-terminus. Total precursor protein is 671 aa of which only 268 aa are in the finally processed exoenzyme.


Assuntos
Gammaproteobacteria/enzimologia , Expressão Gênica , RNA Ribossômico 16S/análise , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Dados de Sequência Molecular , Peso Molecular , Mapeamento de Peptídeos , RNA Ribossômico 16S/genética , Homologia de Sequência de Aminoácidos , Serina Endopeptidases/genética , Serina Endopeptidases/isolamento & purificação , Microbiologia do Solo
3.
J Agric Food Chem ; 59(18): 10211-8, 2011 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21815692

RESUMO

Eleven odor-active thiols, namely, 2-methyl-1-propene-1-thiol, (Z)-3-methyl-1-butene-1-thiol, (E)-3-methyl-1-butene-1-thiol, (Z)-2-methyl-1-butene-1-thiol, (E)-2-methyl-1-butene-1-thiol, 2-methyl-3-furanthiol, 3-mercapto-2-pentanone, 2-mercapto-3-pentanone, 4-mercapto-3-hexanone, 3-mercapto-3-methylbutyl formate, and 2-methyl-3-thiophenethiol, recently identified in an extract prepared from white sesame seeds, were quantitated in sesame using stable isotope dilution analyses. For that purpose, the following deuterium-labeled compounds were synthesized and used as internal standards in the quantitation assays: [2H6]-2-methyl-1-propene-1-thiol, [2H3]-(E)- and [2H3]-(Z)-2-methyl-1-butene-1-thiol, [2H3]-2-methyl-3-furanthiol, [2H2]-3-mercapto-2-pentanone, [2H3]-4-mercapto-3-hexanone, [2H6]-3-mercapto-3-methylbutyl formate, and [2H3]-2-methyl-3-thiophenethiol. On the basis of the results obtained, odor activity values (OAVs) were calculated as ratio of the concentration and odor threshold of the individual compounds in cooking oil. According to their high OAVs, particularly the 3-methyl-1-butene-1-thiols (OAV: 2400) and the 2-methyl-1-butene-1-thiols (OAV: 960) were identified as the most odor-active compounds in pan-roasted white sesame seeds. These compounds were therefore suggested to be mainly responsible for the characteristic but rather unstable sulfury aroma of freshly pan-roasted white sesame seeds.


Assuntos
Temperatura Alta , Odorantes/análise , Sementes/química , Sesamum/química , Compostos de Sulfidrila/análise , Deutério , Técnicas de Diluição do Indicador
4.
J Agric Food Chem ; 58(12): 7368-75, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20491509

RESUMO

Screening for aroma-active compounds in an aroma distillate obtained from freshly pan-roasted sesame seeds by aroma extract dilution analysis revealed 32 odorants in the FD factor range of 2-2048, 29 of which could be identified. The highest FD factors were found for the coffee-like smelling 2-furfurylthiol, the caramel-like smelling 4-hydroxy-2,5-dimethyl-3(2H)-furanone, the coffee-like smelling 2-thenylthiol (thiophen-2-yl-methylthiol), and the clove-like smelling 2-methoxy-4-vinylphenol. In addition, 9 odor-active thiols with sulfurous, meaty, and/or catty, black-currant-like odors were identified for the first time in roasted sesame seeds. Among them, 2-methyl-1-propene-1-thiol, (Z)-3-methyl-1-butene-1-thiol, (E)-3-methyl-1-butene-1-thiol, (Z)-2-methyl-1-butene-1-thiol, (E)-2-methyl-1-butene-1-thiol, and 4-mercapto-3-hexanone were previously unknown as food constituents. Their structures were confirmed by comparing their mass spectra and retention indices as well as their sensory properties with those of synthesized reference compounds. The relatively unstable 1-alkene-1-thiols represent a new class of food odorants and are suggested as the key contributors to the characteristic, but quickly vanishing, aroma of freshly ground roasted sesame seeds.


Assuntos
Sesamum/química , Compostos de Sulfidrila/química , Compostos Orgânicos Voláteis/química , Manipulação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Odorantes/análise , Sementes/química
5.
J Am Chem Soc ; 125(51): 16114-26, 2003 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-14678004

RESUMO

Iridium-catalyzed borylation of benzene with diboron was theoretically investigated with the DFT method, where an iridium(I) boryl complex, Ir(Beg)(NN) 1, and an iridium(III) tris(boryl) complex, Ir(Beg)(3)(NN) 14, (eg (ethyleneglycolato) = -OCH(2)CH(2)O-, NN = HN=CHCH=NH (diim) or 2,2'-bipyridine (bpy)) were adopted as models of active species and B(2)(eg)(2) was adopted as a model of bis(pinacolato)diboron (pinacolato = -OCMe(2)CMe(2)O-). Oxidative addition of a benzene C-H sigma-bond to 1 takes place with an activation barrier (E(a)) of 11.2 kcal/mol, followed by reductive elimination of phenylborane, Ph-Beg, from Ir(Beg)(H)(Ph)(diim) with an activation barrier of 15.6 kcal/mol. Though the oxidative addition and the reductive elimination occur with moderate activation barriers, B(2)(eg)(2) much more easily reacts with 1 to afford 14 than does benzene, of which the activation barrier is very small (2.9 kcal/mol). Oxidative addition of the benzene C-H sigma-bond to 14 occurs with a moderate activation barrier of 24.2 kcal/mol to afford an unusual seven-coordinate iridium(V) complex, Ir(H)(Ph)(Beg)(3)(bpy) 16. From this complex, phenylborane Ph-Beg is produced through the reductive elimination with concomitant formation of IrH(Beg)(2)(bpy) 17, where the activation barrier is 4.9 kcal/mol. Complex 17 further reacts with diboron to form Ir(H)(Beg)(4)(bpy) (E(a) = 8.0 kcal/mol), followed by the reductive elimination of borane H-Beg (E(a) = 2.6 kcal/mol) to regenerate Ir(Beg)(3)(bpy), when diboron exists in excess in the reaction solution. After consumption of diboron, IrH(Beg)(2)(bpy) reacts with borane, H-Beg, to form Ir(H)(2)(Beg)(3) (E(a) = 21.3 kcal/mol) followed by the reductive elimination of H(2), to regenerate Ir(Beg)(3)(bpy) with concomitant formation of H(2). Formation of the iridium(III) tris(boryl) complex 14 from IrCl(diim) and diboron was also theoretically investigated; IrCl(diim) undergoes two steps of oxidative addition of diboron to afford a seven-coordinate iridium(V) complex, IrCl(Beg)(4)(NN), from which the reductive elimination of Cl-Beg takes place easily to afford 14. From these results, it should be clearly concluded that the iridium(III) tris(boryl) complex is an active species and an unusual iridium(V) species is involved as a key intermediate in the reaction. Detailed discussion is presented on the full catalytic cycle and the importance of a seven-coordinate iridium(V) intermediate.

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