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1.
Anal Bioanal Chem ; 416(23): 5165-5175, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39078454

RESUMO

Food allergens in processed foods are affected by heating, processing, and the food matrix. To conduct highly reliable tests, extracting allergens into test solutions is necessary for appropriate detection. In addition to the commonly used enzyme-linked immunosorbent assay (ELISA), liquid chromatography-mass spectrometry (LC-MS), which has the advantage of simultaneously detecting multiple allergens in foods, is being increasingly used. When managing food allergens at food manufacturing sites, obtaining the same measured values is desirable, regardless of the analytical method used. Therefore, in this study, we focused on the importance of pretreatment steps for LC-MS when examining food allergens in processed foods, which can be difficult to analyze. The ELISA method uses food extracts optimized for analyzing allergens in processed foods. We developed a high-resolution accurate mass spectrometry (HRAM)-LC-MS/MS method using the same food extract used in the ELISA method and an MS sample preparation kit. Multiple food allergen analysis was performed using 1, 5, 10, and 20 ppm of allergen-incurred processed foods. Overall, a strong correlation was observed between the measured values of HRAM-LC-MS/MS and ELISA, demonstrating the applicability of multi-allergen analysis using LC-MS.


Assuntos
Alérgenos , Ensaio de Imunoadsorção Enzimática , Análise de Alimentos , Espectrometria de Massas em Tandem , Ensaio de Imunoadsorção Enzimática/métodos , Alérgenos/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Hipersensibilidade Alimentar , Limite de Detecção , Espectrometria de Massa com Cromatografia Líquida , Alimento Processado
2.
Int J Clin Oncol ; 28(5): 654-663, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36856908

RESUMO

BACKGROUND: Oncogenic mutations in BRAF genes are found in approximately 5-10% of colorectal cancers. The majority of BRAF mutations are located within exons 11-15 of the catalytic kinase domains, with BRAF V600E accounting for more than 80% of the observed BRAF mutations. Sensitivity to BRAF- and mitogen-activated protein kinase (MEK) inhibitors varies depending on BRAF mutations and tumor cell types. Previously, we newly identified, BRAF L525R-mutation, in the activation segment of the kinase in colorectal cancer patient. Here, we characterized the function of the BRAF L525R mutation. METHODS: HEK293 cells harboring a BRAF mutation (V600E or L525R) were first characterized and then treated with cetuximab, dabrafenib, and selumetinib. Cell viability was measured using WST-1 assay and the expression of proteins involved in the extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) signaling pathways was evaluated using western blot analysis. RESULTS: The MEK inhibitor selumetinib effectively inhibited cell proliferation and ERK phosphorylation in BRAF L525R cells but not in BRAF V600E cells. Further studies revealed that AKT phosphorylation was reduced by selumetinib in BRAF L525R cells but not in BRAF V600E cells or selumetinib-resistant BRAF L525R cells. Moreover, the AKT inhibitor overcame the selumetinib resistance. CONCLUSIONS: We established a model system harboring BRAF L525R using HEK293 cells. BRAF L525R constitutively activated ERK. AKT phosphorylation caused sensitivity and resistance to selumetinib. Our results suggest that a comprehensive network analysis may provide insights to identify effective therapies.


Assuntos
Proteínas Proto-Oncogênicas B-raf , Proteínas Proto-Oncogênicas c-akt , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Células HEK293 , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Mutação , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo
3.
Anal Bioanal Chem ; 410(2): 325-335, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29138881

RESUMO

Food allergy is a serious health issue worldwide. Implementing allergen labeling regulations is extremely challenging for regulators, food manufacturers, and analytical kit manufacturers. Here we have developed an "amino acid sequence immunoassay" approach to ELISA. The new ELISA comprises of a monoclonal antibody generated via an analyte specific peptide antigen and sodium lauryl sulfate/sulfite solution. This combination enables the antibody to access the epitope site in unfolded analyte protein. The newly developed ELISA recovered 87.1%-106.4% ovalbumin from ovalbumin-incurred model processed foods, thereby demonstrating its applicability as practical egg allergen determination. Furthermore, the comparison of LC-MS/MS and the new ELISA, which targets the amino acid sequence conforming to the LC-MS/MS detection peptide, showed a good agreement. Consequently the harmonization of two methods was demonstrated. The complementary use of the new ELISA and LC-MS analysis can offer a wide range of practical benefits in terms of easiness, cost, accuracy, and efficiency in food allergen analysis. In addition, the new assay is attractive in respect to its easy antigen preparation and predetermined specificity. Graphical abstract The ELISA composing of the monoclonal antibody targeting the amino acid sequence conformed to LC-MS detection peptide, and the protein conformation unfolding reagent was developed. In ovalbumin determination, the developed ELISA showed a good agreement with LC-MS analysis. Consequently the harmonization of immunoassay with LC-MS analysis by using common target amino acid sequence was demonstrated.


Assuntos
Alérgenos/análise , Ensaio de Imunoadsorção Enzimática/métodos , Ovalbumina/análise , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Cromatografia Líquida/métodos , Hipersensibilidade a Ovo/diagnóstico , Feminino , Análise de Alimentos/métodos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Espectrometria de Massas em Tandem/métodos , Vinho/análise
4.
Radiology ; 279(1): 56-64, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26458207

RESUMO

PURPOSE: To investigate the relationship between spiculated masses at mammography and marginal adipose tissue invasion at histologic examination. MATERIALS AND METHODS: The institutional review board approved this retrospective study, and the requirement to obtain informed consent was waived. A total of 478 patients with invasive breast cancer who underwent surgery between 1999 and 2009 were included in this study. Clinical-pathologic findings from patients with spiculated masses on mammograms were compared with those from patients without spiculated masses by using logistic regression models, Cox proportional hazards regression models, and the Kaplan-Meier method. RESULTS: There were 136 spiculated tumors and 342 nonspiculated tumors. All 136 spiculated tumors (100%) were positive for adipose tissue invasion, whereas only 264 of the 342 nonspiculated tumors (77%) were positive for adipose tissue invasion (P < .001). Multivariate analysis revealed that adipose tissue invasion (P < .001), histologic grade (P < .001), dense breast (P = .002), and body mass index (P = .02) were independent factors associated with spiculation. With regard to survival, although many patients with spiculated tumors had a hormone-sensitive (estrogen receptor positive: P = .004; progesterone receptor positive: P = .001) or low-grade (P < .001) tumor, in contrast to the patients without spiculated masses, the prognosis in the two groups was similar (disease-free survival: P = .09; overall survival: P = .23). CONCLUSION: Cancer cell interaction with adipose tissue is crucial for the finding of spiculation at mammography.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Tecido Adiposo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Mamografia , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica/diagnóstico por imagem , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Taxa de Sobrevida
5.
J Appl Glycosci (1999) ; 71(2): 47-54, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863952

RESUMO

Super Ohtaka®, a fermented beverage of plant extracts, is prepared from approximately 50 kinds of fruits and vegetables. Natural fermentation is mainly performed by lactic acid bacteria (Leuconostoc spp.) and yeast (Zygosaccharomyces spp.). Four water-soluble polysaccharide fractions were obtained from Super Ohtaka® by dialysis, ion exchange chromatography, and gel filtration chromatography; these fractions were designated as OEP1-1, OEP1-2, OEP2, and OEP3. OEP1-1 is a polysaccharide composed solely of glucose. The other fractions contained polysaccharides composed of glucose, galactose, mannose, and a small amount of arabinose. OEP2 and OEP3 contained phosphorus, which was not detected in OEP1-1 and OEP1-2. Furthermore, the immunomodulatory activity of the polysaccharides was investigated in murine macrophage cell lines. OEP2 and OEP3 significantly induced nitric oxide (NO) secretion by macrophages in a dose-dependent manner (concentration range of 4 to 100 µg/mL). When the concentration of OEP3 was 100 µg/mL, NO production was almost identical to lipopolysaccharide (LPS; 10 ng/mL) used as a positive control. Notably, OEP3 induced NO secretion more strongly than OEP2. This trend was also observed for TNF-α, IL-1ß, IL-6, and IL-12 p40 secretion. Overall, our in vitro studies on polysaccharides isolated from Super Ohtaka® suggest that the fermented beverage stimulates macrophages and activates the immune system.

6.
Appl Spectrosc ; 76(6): 699-711, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35081767

RESUMO

The heat treatment of an injection-molded polyoxymethylene slightly below the melting point and subsequent isothermal treatment at 130 °C were performed. The polyoxymethylene structure was examined using field-emission scanning electron microscopy and polarization infrared reflection measurements. After the heat treatment, a significant change in the surface morphology was observed, and the reflection spectrum derived from the polariton in the injection direction also changed dramatically. Since the reflection spectrum in the injection direction contains the reflection component of the perpendicular direction and vice versa, the polarization spectra of both directions can be calculated consistently. The mixing ratio of each crossed component and the pure relative permittivity both parallel and perpendicular to the main-chain direction were determined using the oscillator model. The heat treatment reduced the ratio of the perpendicular component and increased the order structure until just before melting. The structural changes characterized by the two techniques, along with Raman spectroscopy and differential scanning calorimetry, are discussed.


Assuntos
Análise Espectral Raman , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Resinas Sintéticas , Espectrofotometria Infravermelho
7.
Biosci Biotechnol Biochem ; 74(10): 2130-2, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20944409

RESUMO

The synthesis is reported of ß-D-fructopyranosyl-(2→6)-D-glucopyranose that had previously been isolated from a fermented plant extract as a new saccharide. A disaccharide was predominately formed from an equal amount of D-glucose and D-fructose under melting conditions at 140 °C for 60 to 90 min. This saccharide was isolated from the reaction mixture by carbon-Celite column chromatography and preparative HPLC, and was confirmed to be ß-D-fructopyranosyl-(2→6)-D-glucopyranose by TOF-MS and NMR analyses.


Assuntos
Dissacarídeos/síntese química , Frutose/química , Glucose/química , Temperatura , Dissacarídeos/química , Indústria Alimentícia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
8.
Jpn J Infect Dis ; 72(6): 381-386, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31257238

RESUMO

In this study, we evaluated extended-spectrum ß-lactamase (ESBL)-producing bacteria with the newly developed primer and probe sets to detect blaCTX-M, blaTEM, and blaSHV using BD MAXTM, a fully automated multiplex polymerase chain reaction assay system. In 36 isolates confirmed by whole-genome sequencing to have blaCTX-M, blaTEM, or blaSHV, the developed primer and probe sets accurately detected each gene without being influenced by the presence of other ß-lactamase genes. In nine control strains that do not harbor either blaCTX-M, blaTEM, or blaSHV no cross-reaction was observed. In 191 strains phenotypically determined to be ESBL-producers by conventional antimicrobial susceptibility tests, 189 strains were blaCTX-M-, blaTEM-, or blaSHV-positive as assessed by BD MAXTM using the developed primer and probe sets, and two strains were negative for these genes. Whole-genome sequencing revealed that these two strains were phenotypically false-positive ESBL-producers. The accuracy of the primer and probe sets seems to be satisfactory, and they may be applicable to detect CTX-M-type ESBL-producing bacteria.


Assuntos
Automação Laboratorial , Primers do DNA/genética , Sondas de DNA/genética , Escherichia coli/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Infecções por Escherichia coli/microbiologia , Reações Falso-Positivas , Humanos , Testes de Sensibilidade Microbiana , Reprodutibilidade dos Testes , Sequenciamento Completo do Genoma
9.
Carbohydr Res ; 343(3): 549-54, 2008 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-18096146

RESUMO

An extract from 50 kinds of fruits and vegetables was fermented to produce a new beverage. Natural fermentation of the extract was carried out mainly by lactic acid bacteria (Leuconostoc spp.) and yeast (Zygosaccharomyces spp. and Pichia spp.). Two new saccharides were found in this fermented beverage. The saccharides were isolated using carbon-Celite column chromatography and preparative high performance liquid chromatography. Gas liquid chromatography analysis of methylated derivatives as well as MALDI-TOF MS and NMR measurements were used for structural confirmation. The (1)H and (13)C NMR signals of each saccharide were assigned using 2D-NMR including COSY, HSQC, HSQC-TOCSY, CH(2)-HSQC-TOCSY, and CT-HMBC experiments. The saccharides were identified as beta-D-fructopyranosyl-(2-->6)-beta-D-glucopyranosyl-(1-->3)-D-glucopyranose and beta-D-fructopyranosyl-(2-->6)-[beta-D-glucopyranosyl-(1-->3)]-D-glucopyranose.


Assuntos
Bebidas , Fermentação , Oligossacarídeos , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia , Leuconostoc/metabolismo , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/biossíntese , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Extratos Vegetais/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Zygosaccharomyces/metabolismo
10.
J Craniofac Surg ; 19(4): 1167-70, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18650753

RESUMO

Nodular fasciitis is a benign reactive proliferation that is frequently misdiagnosed as a sarcoma. This article describes a case of nodular fasciitis of 6-month duration located in the cheek, which degenerated and spontaneously regressed after biopsy. The nodule was fixed to the zygoma but was free from the overlying skin. The mass was 3.0 cm in diameter and demonstrated high signal intensity on T2-weighted magnetic resonance imaging. A small part of the lesion was biopsied. Pathological and immunohistochemical examinations identified the nodule as nodular fasciitis with myxoid histology. One month after the biopsy, the mass showed decreased signal intensity on T2-weighted images and measured 2.2 cm in size. The signal on T2-weighted images showed time-dependent decreases, and the mass continued to reduce in size throughout the follow-up period. The lesion presented as hypointense to the surrounding muscles on T2-weighted images and was 0.4 cm in size at 2 years of follow-up. This case demonstrates that nodular fasciitis with myxoid histology can change to that with fibrous appearance gradually with time, thus bringing about spontaneous regression. Degeneration may be involved in the spontaneous regression of nodular fasciitis with myxoid appearance. The mechanism of regression, unclarified at present, should be further studied.


Assuntos
Fasciite/patologia , Fibroblastos/patologia , Adulto , Biópsia , Proliferação de Células , Bochecha , Fasciite/classificação , Feminino , Humanos , Imageamento por Ressonância Magnética , Remissão Espontânea
11.
J Appl Glycosci (1999) ; 64(1): 15-19, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-34354491

RESUMO

The synthesis of the saccharide ß-D-fructopyranosyl-(2→6)-D-glucopyranose, which was isolated from Super Ohtaka®, has recently been reported. During the synthesis of this saccharide, the formation of two novel saccharides from D-glucose and D-fructose was observed. The present study aimed to confirm the structures of the two disaccharides synthesized from D-glucose and D-fructose by thermal treatment. Furthermore, various properties of the saccharides were investigated. Both saccharides were isolated from the reaction mixture by carbon-Celite column chromatography and an HPLC system and were determined to be novel sucrose-isomers, ß-D-fructopyranosyl-(2↔1)-ß-D-glucopyranoside (1) and ß-D-fructofuranosyl-(2↔1)-ß-D-glucopyranoside (2), by MALDI-TOF MS and NMR analyses. Both saccharides showed low digestibility in vitro, and the sweetness of saccharide 2 was 0.45 times that of sucrose.

12.
J Appl Glycosci (1999) ; 64(4): 123-127, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-34354505

RESUMO

A fermented beverage of plant extracts (Super Ohtaka®) was prepared from about 50 kinds of fruits and vegetables. This natural fermentation was performed by yeast (Zygosaccharomyces spp. and Pichia spp.) and lactic acid bacteria (Leuconostoc spp.) and resulted in the production of a novel fructopyranose-containing saccharide, which was subsequently isolated using carbon-Celite column chromatography and preparative-HPLC. The structure of the saccharide was determined using MALDI-TOF MS and NMR, and the saccharide was identified as ß-D-fructopyranosyl-(2→6)-ß-D-fructofuranosyl-(2↔1)-α-D-glucopyranoside. This is the first description of this novel saccharide and its isolation from a natural source.

13.
Carbohydr Res ; 341(7): 925-9, 2006 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-16530174

RESUMO

Fermented beverage of plant extract was prepared from about 50 kinds of vegetables and fruits. Natural fermentation was carried out mainly by lactic acid bacteria (Leuconostoc spp.) and yeast (Zygosaccharomyces spp. and Pichia spp.). Three kinds of saccharides have been found in this beverage and produced by fermentation. The saccharides isolated from the beverage using carbon-Celite column chromatography and preparative HPLC, were identified as a new saccharide, beta-d-fructopyranosyl-(2-->6)-d-glucopyranose, laminaribiose and maltose by examination of constituted sugars, GLC and GC-MS analyses of methyl derivatives and MALDI-TOF-MS and NMR measurements of the saccharides.


Assuntos
Bebidas/microbiologia , Fermentação , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Leuconostoc/metabolismo , Ressonância Magnética Nuclear Biomolecular , Pichia/metabolismo , Extratos Vegetais/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Zygosaccharomyces/metabolismo
14.
J Biosci Bioeng ; 99(3): 252-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16233785

RESUMO

The growth inhibition of Moorella sp. HUC22-1 by undissociated acetic acid was analyzed using a non-competitive inhibition model coupled with a pH inhibition model. In the cells grown on H2 and CO2, the inhibition constant, K(p) of the undissociated acetic acid was 6.2 mM (164 mM as the total acetate at pH 6.2, pKa = 4.795, 55 degrees C), which was 1.5-fold higher than that obtained in cells grown on fructose. When a pH-controlled batch culture was performed using a fermentor at pH 6.2 with H2 and CO2, a maximum of 0.92 g/l of dry cell weight and 339 mM of acetate were produced after 220 h, which were 4.4- and 6.8-fold higher than those produced in the pH-uncontrolled batch culture, respectively. In order to reduce acetate inhibition in the culture medium, a repeated batch culture with cell recycling was performed at a constant pH with H2 and CO2. At a pH of 6.2, the total acetate production reached 840 mmol/l-reactor with 4.7 mmol/l-reactor of total ethanol production after 420 h. When the culture pH was maintained at 5.8, which was the optimum for ethanol production, the total ethanol production reached 15.4 mmol/l-reactor after 430 h, although the total acetate production was decreased to 675 mmol/l-reactor.


Assuntos
Acetatos/metabolismo , Reatores Biológicos/microbiologia , Dióxido de Carbono/metabolismo , Técnicas de Cultura de Células/métodos , Etanol/metabolismo , Hidrogênio/metabolismo , Thermoanaerobacter/metabolismo , Ácido Acético/metabolismo , Ácido Acético/farmacologia , Concentração de Íons de Hidrogênio , Thermoanaerobacter/efeitos dos fármacos
15.
J Biosci Bioeng ; 100(4): 398-402, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16310728

RESUMO

Mycobacterium sp. G3 was reported as a dibenzothiophene (DBT)-degrading microorganism and the first strain to have the ability to degrade high-molecular-weight alkyl DBTs, such as 4,6-dibutyl DBT and 4,6-dipentyl DBT, by the C-S bond cleavage pathway. Three genes (mdsA, mdsB, and mdsC) for desulfurization, which form a cluster, were cloned from Mycobacterium sp. G3. The expression of each gene in Escherichia coli JM109 showed that MdsC oxidized DBT to DBT sulfone, MdsA transformed DBT sulfone into 2-(2'-hydroxyphenyl)benzene sulfinate (HPBS), and MdsB desulfinated HPBS into 2-hydroxybiphenyl (HBP), indicating that the gene products of mdsABC are functional in the recombinant. MdsC oxidized 4,6-dimethyl DBT, 4,6-diethyl DBT, 4,6-dipropyl DBT and 4,6-dibutyl DBT to each sulfone form, suggesting that MdsC covers a broad specificity for alkyl DBTs.


Assuntos
Genes Bacterianos , Mycobacterium/enzimologia , Mycobacterium/genética , Tiofenos/metabolismo , Biodegradação Ambiental , Clonagem Molecular , Escherichia coli/genética , Especificidade por Substrato , Enxofre/metabolismo
16.
J Org Chem ; 61(9): 2972-2979, 1996 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-11667156

RESUMO

Acid-catalyzed rearrangement of 5-cyclopentylidenecyclooctanone derivatives 9a-c was examined to obtain polyspiropolyquinanes 11a-c, considered to have a unique helical structure, through cascade rearrangement pathways consisting of continuous transannular cyclization followed by successive 1,2-alkyl shifts. The substrates were prepared easily by use of the Wittig or McMurry reaction. Reaction of the 5-cyclopentylidenecyclooctanone (9a) with acid gave the expected dispirotriquinane ketone 11a in high yield. The precise mechanism was elucidated by a deuterium-labeling experiment. In the case of the ketone 9b, having another spiroannulated cyclopentane ring attached on 9a, the trispirotetraquiane 11b was not obtained but the bis-propellane-type tetrahydrofuran 25 was produced exclusively. The 5-(5'-cyclopentylidenecyclooctylidene)cyclooctanone (9c) afforded the polycyclic compounds 27-31, depending on the acid used, instead of the desired tetraspiropentaquinane 11c. The structures of the products were determined by NMR spectral data including 2D (13)C INADEQUATE spectra and X-ray crystallographic analyses. The unexpected rearrangement pathways are also discussed.

17.
Carbohydr Res ; 338(9): 879-85, 2003 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-12681912

RESUMO

Five novel oligosaccharides (tetra-, penta- and hexa-saccharides) were synthesized by glucosyltransfer from beta-D-glucose 1-phosphate to isokestose (O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-alpha-D-glucopyranoside) or nystose (O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-alpha-D-glucopyranoside) using Thermoanaerobacter brockii kojibiose phosphorylase. The oligosaccharides were identified as 2(2-alpha-D-glucopyranosyl)(m)isokestose; [O-alpha-D-glucopyranosyl-(1-->2)](m)-O-[beta-D-fructofuranosyl-(2-->1)](2)-alpha-D-glucopyranoside: m=1, 2, and 3, and 2(2-alpha-D-glucopyranosyl)(n)nystose; [O-alpha-D-glucopyranosyl-(1-->2)](n)-O-[beta-D-fructofuranosyl-(2-->1)](3)-alpha-D-glucopyranoside: n=1 and 2 using gas liquid chromatography analysis of the methyl derivatives, and MALDI-TOF-MS and NMR measurements of the newly formed oligosaccharides. 1H, 13C NMR signals of each saccharide were assigned using 2D-NMR techniques, including COSY, HSQC, HSQC-TOCSY, HMBC, CH(2)-selected E-HSQC, and CH(2)-selected E-HSQC-TOCSY.


Assuntos
Bactérias Anaeróbias/enzimologia , Dissacarídeos/metabolismo , Glucofosfatos/química , Oligossacarídeos/química , Oligossacarídeos/síntese química , Fosforilases/metabolismo , Trissacarídeos/química , Configuração de Carboidratos , Sequência de Carboidratos , Temperatura Alta , Cinética , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/isolamento & purificação
18.
J Biosci Bioeng ; 93(2): 228-33, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-16233192

RESUMO

The substrate specificity of Mycobacterium sp. G3 with desulfurization activity against dibenzothiophene (DBT) was investigated. Desulfurization reactions were carried out using a concentrated cell suspension of G3. The conversion from 4,6-dipropyl DBT, one of the sulfur-containing compounds that is difficult to desulfurize in diesel oil, to 2-hydroxy-3,3'-dipropylbiphenyl as an end -product of the desulfurization reaction was found in the water reaction system and in the oil/water two-phase reaction system. 4,6-Dibutyl DBT and 4,6-dipentyl DBT were metabolized to the hydroxybiphenyl form via the sulfone form in the water reaction system. These results indicate that G3 has high membrane permeability and superior substrate specificity for high molecular weight alkyl DBTs, which are represented by 4,6-dipentyl DBT as C10-DBT. Furthermore, G3 could desulfurize diesel oil, and the sulfur concentration was decreased from 116 mg l(-1) to 48 mg l(-1) within 24 h.

19.
J Biosci Bioeng ; 93(5): 491-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-16233237

RESUMO

The dibenzothiophene (DBT) metabolic pathway in Mycobacterium strain G3, which is classified as a desulfurizing microorganism with the 4S pathway, was analyzed. 2-Hydroxybiphenyl (HBP), which is an end metabolite in the DBT desulfurization reaction, and 2-methoxybiphenyl (MBP) were found in the reaction mixture, and the methoxylation pathway from HBP to MBP was clarified. Although the substrate in the methoxylation reaction was HBP, there was no relationship between expression of the methoxylation activity and that of the desulfurization activity. Then, 4,6-dimethyl DBT, 4,6-diethyl DBT and benzo[b]naphtho[2,1-d]thiophene were metabolized to their methoxy forms via the desulfurization pathway. We established the methoxylation pathway in Mycobacterium G3.

20.
Hepatogastroenterology ; 51(57): 771-3, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15143913

RESUMO

Ileosigmoid knot is one of the causes of intestinal obstruction, but it is very difficult to make a correct preoperative diagnosis of the disease. This rare condition with high mortality is usually found in adult patients and has rarely been reported in children. We recently experienced two patients with ileosigmoid knot. One was a 4-year-old boy and the other a 60-year-old man. Both patients had suffered the sudden onset of abdominal pain. The boy was in a state of shock on admission. Abdominal computed tomography findings indicated intestinal obstruction. In laparotomy, intestinal resection and detorsion without resection were performed for the boy and adult patients, respectively. We herein report a case of ileosigmoid knot in which the patient was the youngest reported in the English literature, and showed that the computed tomography examination provided valuable information in both patients.


Assuntos
Doenças do Íleo/diagnóstico por imagem , Doenças do Colo Sigmoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Pré-Escolar , Humanos , Doenças do Íleo/complicações , Masculino , Pessoa de Meia-Idade , Doenças do Colo Sigmoide/complicações
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