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1.
Curr Issues Mol Biol ; 46(6): 5794-5811, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38921017

RESUMEN

Colorectal cancer, the third most commonly occurring tumor worldwide, poses challenges owing to its high mortality rate and persistent drug resistance in metastatic cases. We investigated the tumor microenvironment, emphasizing the role of cancer-associated fibroblasts in the progression and chemoresistance of colorectal cancer. We used an indirect co-culture system comprising colorectal cancer organoids and cancer-associated fibroblasts to simulate the tumor microenvironment. Immunofluorescence staining validated the characteristics of both organoids and fibroblasts, showing high expression of epithelial cell markers (EPCAM), colon cancer markers (CK20), proliferation markers (KI67), and fibroblast markers (VIM, SMA). Transcriptome profiling was conducted after treatment with anticancer drugs, such as 5-fluorouracil and oxaliplatin, to identify chemoresistance-related genes. Changes in gene expression in the co-cultured colorectal cancer organoids following anticancer drug treatment, compared to monocultured organoids, particularly in pathways related to interferon-alpha/beta signaling and major histocompatibility complex class II protein complex assembly, were identified. These two gene groups potentially mediate drug resistance associated with JAK/STAT signaling. The interaction between colorectal cancer organoids and fibroblasts crucially modulates the expression of genes related to drug resistance. These findings suggest that the interaction between colorectal cancer organoids and fibroblasts significantly influences gene expression related to drug resistance, highlighting potential biomarkers and therapeutic targets for overcoming chemoresistance. Enhanced understanding of the interactions between cancer cells and their microenvironment can lead to advancements in personalized medical research..

2.
Environ Microbiol ; 23(7): 3499-3522, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33830651

RESUMEN

The yeast species Hyphopichia is common in nature and strongly competitive under harsh environmental conditions. Here, we characterized Hyphopichia burtonii KJJ43 and H. pseudoburtonii KJS14, which exhibit strong halotolerance, using genomic and transcriptomic analyses. The genomes of H. burtonii and H. pseudoburtonii comprised eight chromosomes with 85.17% nucleotide identity and significant divergence in synteny. Notably, both Hyphopichia genomes possessed extended gene families of amino acid permeases and ATP-binding cassette (ABC) transporters, whose dynamic expression patterns during osmotic stress were revealed using transcriptome profiling. Intriguingly, we found unique features of the HOG pathway activated by Hog1p even under non-osmotic stress conditions and the upregulation of cytosolic Gpd1 protein during osmotic stress. Associated with hyperfilamentation growth under high osmotic conditions, a set of genes in the FLO family with induced expression in response to NaCl, KCl, and sorbitol supplementation were identified. Moreover, comparative transcriptome analysis reveals the NaCl-specific induction of genes involved in amino acid biosynthesis and metabolism, particularly BAT2. This suggests the potential association between oxoacid reaction involving branched-chain amino acids and osmotolerance. The combined omics analysis of two Hyphopichia species provides insights into the novel mechanisms involved in salt and osmo-stress tolerance exploited by diverse eukaryotic organisms.


Asunto(s)
Saccharomycetales , Transcriptoma , Perfilación de la Expresión Génica , Genómica , Saccharomycetales/genética , Transcriptoma/genética
3.
Molecules ; 24(7)2019 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-30987370

RESUMEN

Styrene can be formed by the microbial metabolism of bacteria and fungi. In our previous study, styrene was determined as a spoilage marker of Fuji apples decayed by Penicillium expansum, which is responsible for postharvest diseases. In the present study, P. expansum was cultivated in potato dextrose broth added with phenylalanine-which is a precursor of styrene-using different initial pH values and cultivation times. Volatile compounds were extracted and analyzed using gas chromatography-mass spectrometry (GC-MS) combined with stir-bar sorptive extraction. The 76 detected volatile compounds included 3-methylbutan-1-ol, 3-methyl butanal, oct-1-en-3-ol, geosmin, nonanal, hexanal, and γ-decalactone. In particular, the formation of 10 volatile compounds derived from phenylalanine (including styrene and 2-phenylethanol) showed different patterns according to pH and the cultivation time. Partial least square-discriminant analysis (PLS-DA) plots indicated that the volatile compounds were affected more by pH than by the cultivation time. These results indicated that an acidic pH enhances the formation of styrene and that pH could be a critical factor in the production of styrene by P. expansum. This is the first study to analyze volatile compounds produced by P. expansum according to pH and cultivation time and to determine their effects on the formation of styrene.


Asunto(s)
Concentración de Iones de Hidrógeno , Penicillium/metabolismo , Estireno/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Fenilalanina/metabolismo , Estireno/química , Compuestos Orgánicos Volátiles/química
4.
Molecules ; 23(11)2018 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-30366381

RESUMEN

Saccharomycopsis fibuligera KJJ81 isolated from nuruk is an amylolytic yeast that is widely used as a microbial starter in various fermented foods. Volatile and nonvolatile metabolites of S. fibuligera KJJ81 were investigated according to different carbon sources and cultivation times using a nontargeted metabolomic approach. Partial-least-squares discriminant analysis was applied to determine the major metabolites, which were found to be closely related to the clustering and discrimination of S. fibuligera KJJ81 samples. Some volatile metabolites derived from phenylalanine, such as 2-phenylethanol, 2-phenylethyl acetate, and ethyl phenylacetate, were predominantly found in cultivation medium containing glucose (YPD medium). In addition, the level of 2-phenylethanol increased continuously with the cultivation time. In terms of nonvolatile metabolites, carbohydrates (mannose, arabitol, and mannitol), fatty acids (palmitic acid and stearic acid), organic acids (oxalic acid and succinic acid), and amino acids (isoleucine, serine, alanine, glutamic acid, glycine, proline, phenylalanine, and threonine) were the main contributors to S. fibuligera KJJ81 samples cultivated in YPD medium according to cultivation time. These results show that the formation of volatile and nonvolatile metabolites of S. fibuligera KJJ81 can be significantly affected by both the carbon sources and the cultivation time.


Asunto(s)
Carbono/metabolismo , Saccharomycopsis/metabolismo , Acetatos/metabolismo , Alanina/metabolismo , Ácido Glutámico/metabolismo , Glicina/metabolismo , Isoleucina/metabolismo , Manitol/metabolismo , Manosa/metabolismo , Fenilacetatos/metabolismo , Fenilalanina/metabolismo , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/metabolismo , Prolina/metabolismo , Serina/metabolismo , Alcoholes del Azúcar/metabolismo , Treonina/metabolismo , Factores de Tiempo
5.
Biosci Biotechnol Biochem ; 81(3): 565-572, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27869536

RESUMEN

Lichtheimia ramosa is one of the predominant filamentous fungi in Korean traditional nuruk. The nonvolatile and volatile metabolites of L. ramosa cultivated in three growth media: complete medium (CM), potato dextrose broth (PDB), and sabouraud dextrose broth (SDB), were investigated and compared. Among nonvolatile metabolites, serine, lysine, and ornithine increased in CM and PDB cultivated with L. ramosa during the exponential phase. In addition, glucose level increased in CM whereas decreased in PDB and SDB. The major volatile metabolites in the extract samples were acetic acid, ethanol, 3-methyl-2-buten-1-ol, 2-phenylethanol, ethylacetate, 2-furaldehyde, 5-(hydroxymethyl)-2-furaldehyde, 2,3-dihydro-3,5,-dihydroxy-6-methyl-4H-pyran-4-one, and α-humulene. In particular, the levels of volatile metabolites related to makgeolli (e.g., acetic acid, ethanol, and ethyl acetate) were highest in extracts cultivated in CM. On the other hand, the level of 2-phenylethanol was relatively higher in PDB and SDB, possibly due to there being more phenylalanine present in the biomass sample in media.


Asunto(s)
Medios de Cultivo/química , Microbiología de Alimentos , Mucorales/metabolismo , Compuestos Orgánicos Volátiles/análisis , Aminoácidos/análisis , Aminoácidos/metabolismo , Medios de Cultivo/metabolismo , Ciclopentanos/metabolismo , Ácidos Grasos/análisis , Ácidos Grasos/metabolismo , Microbiología de Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Glucosa/metabolismo , Sesquiterpenos Monocíclicos , Mucorales/citología , Mucorales/crecimiento & desarrollo , Alcohol Feniletílico/metabolismo , Sesquiterpenos/metabolismo , Compuestos Orgánicos Volátiles/metabolismo
6.
Nanoscale ; 16(6): 3160-3165, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38259148

RESUMEN

Li intercalation is commonly used to enhance the carrier density in epitaxial graphene and mitigate coupling to the substrate. So far, the understanding of the intercalation process, particularly how Li penetrates different layers above the substrate, and its impact on electron transport remains incomplete. Here, we report different phases of Li intercalation and their kinetic processes in epitaxial mono- and bilayer graphene grown on SiC. The distinct doping effects of each intercalation phase are characterized using scanning tunneling spectroscopy. Furthermore, changes in the local conduction regimes are directly mapped by scanning tunneling potentiometry and attributed to different charge transfer states of the intercalated Li. The stable intercalation marked by the formation of Li-Si bonds leads to a significant 56% reduction in sheet resistance of the resulting quasi-free bilayer graphene, as compared to the pristine monolayer graphene.

7.
Microb Biotechnol ; 16(11): 2161-2180, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37837246

RESUMEN

The industrial potential of Saccharomyces cerevisiae has extended beyond its traditional use in fermentation to various applications, including recombinant protein production. Herein, comparative genomics was performed with three industrial S. cerevisiae strains and revealed a heterozygous diploid genome for the 98-5 and KSD-YC strains (exploited for rice wine fermentation) and a haploid genome for strain Y2805 (used for recombinant protein production). Phylogenomic analysis indicated that Y2805 was closely associated with the reference strain S288C, whereas KSD-YC and 98-5 were grouped with Asian and European wine strains, respectively. Particularly, a single nucleotide polymorphism (SNP) in FDC1, involved in the biosynthesis of 4-vinylguaiacol (4-VG, a phenolic compound with a clove-like aroma), was found in KSD-YC, consistent with its lack of 4-VG production. Phenotype microarray (PM) analysis showed that KSD-YC and 98-5 displayed broader substrate utilization than S288C and Y2805. The SNPs detected by genome comparison were mapped to the genes responsible for the observed phenotypic differences. In addition, detailed information on the structural organization of Y2805 selection markers was validated by Sanger sequencing. Integrated genomics and PM analysis elucidated the evolutionary history and genetic diversity of industrial S. cerevisiae strains, providing a platform to improve fermentation processes and genetic manipulation.


Asunto(s)
Saccharomyces cerevisiae , Vino , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fermentación , Genómica , Fenotipo , Análisis por Micromatrices
8.
Fungal Genet Biol ; 49(7): 511-20, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22634273

RESUMEN

Regulators of G protein signaling (RGS) proteins make up a highly diverse and multifunctional protein family that plays a critical role in controlling heterotrimeric G protein signaling. In this study, seven RGS genes (FgFlbA, FgFlbB, FgRgsA, FgRgsB, FgRgsB2, FgRgsC, and FgGprK) were functionally characterized in the plant pathogenic fungus, Gibberella zeae. Mutant phenotypes were observed for deletion mutants of FgRgsA and FgRgsB in vegetative growth, FgFlbB and FgRgsB in conidia morphology, FgFlbA in conidia production, FgFlbA, FgRgsB, and FgRgsC in sexual development, FgFlbA and FgRgsA in spore germination and mycotoxin production, and FgFlbA, FgRgsA, and FgRgsB in virulence. Furthermore, FgFlbA, FgRgsA, and FgRgsB acted pleiotropically, while FgFlbB and FgRgsC deletion mutants exhibited a specific defect in conidia morphology and sexual development, respectively. Amino acid substitutions in Gα subunits and overexpression of the FgFlbA gene revealed that deletion of FgFlbA and dominant active GzGPA2 mutant, gzgpa2(Q207L), had similar phenotypes in cell wall integrity, perithecia formation, mycotoxin production, and virulence, suggesting that FgFlbA may regulate asexual/sexual development, mycotoxin biosynthesis, and virulence through GzGPA2-dependent signaling in G. zeae.


Asunto(s)
Regulación Fúngica de la Expresión Génica , Gibberella/citología , Gibberella/fisiología , Proteínas RGS/metabolismo , Transducción de Señal , Sustitución de Aminoácidos , Proteínas de Unión al GTP/metabolismo , Eliminación de Gen , Gibberella/genética , Mutagénesis Sitio-Dirigida , Proteínas RGS/genética
9.
J Microbiol ; 60(10): 998-1006, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35984613

RESUMEN

Aspergillus section Nigri is a fungus used industrially because of its ability to produce enzymes such as cellulolytic, amylolytic and proteolytic enzymes. In this study, we obtained twenty-eight strains of Aspergillus section Nigri from the traditional Korean fermentation starter, nuruk, which is known as a mixed culture of enzymatic filamentous fungi and yeasts. All strains were identified as Aspergillus section Nigri through combined phylogenetic analysis using partial ß-tubulin and calmodulin gene sequences. The cellulase, amylase and protease activities of Korean strains were measured and compared with ten reference strains of Aspergillus niger. Most Korean strains showed higher cellulolytic activity than reference strains, and Aspergillus neoniger KCN5 showed the highest ß-glucosidase activity. Two-thirds of the Korean strains showed similar levels of α- and glucoamylase activity as the reference strains. The protease activity of Aspergillus section Nigri strains was the highest at pH 3.0, and A. niger KSJ2 showed the highest acidic protease activity. By comparing ten reference strains and twenty-eight Korean strains, our results suggested useful Aspergillus section Nigri strains from nuruk with high enzyme activity, such as KCN5 and KSJ2, and their potential for industrial applications as enzyme producers.


Asunto(s)
Celulasas , Glucano 1,4-alfa-Glucosidasa , Amilasas , Aspergillus niger/genética , Calmodulina , Fermentación , Glucano 1,4-alfa-Glucosidasa/metabolismo , Péptido Hidrolasas/genética , Filogenia , República de Corea , Tubulina (Proteína)
10.
Metabolites ; 12(11)2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36355095

RESUMEN

Rice (Oryza sativa L.) is a widely consumed food source, and its geographical origin has long been a subject of discussion. In our study, we collected 44 and 20 rice samples from different regions of the Republic of Korea and China, respectively, of which 35 and 29 samples were of white and brown rice, respectively. These samples were analyzed using nuclear magnetic resonance (NMR) spectroscopy, followed by analyses with various data normalization and scaling methods. Then, leave-one-out cross-validation (LOOCV) and external validation were employed to evaluate various machine learning algorithms. Total area normalization, with unit variance and Pareto scaling for white and brown rice samples, respectively, was determined as the best pre-processing method in orthogonal partial least squares-discriminant analysis. Among the various tested algorithms, support vector machine (SVM) was the best algorithm for predicting the geographical origin of white and brown rice, with an accuracy of 0.99 and 0.96, respectively. In external validation, the SVM-based prediction model for white and brown rice showed good performance, with an accuracy of 1.0. The results of this study suggest the potential application of machine learning techniques based on NMR data for the differentiation and prediction of diverse geographical origins of white and brown rice.

11.
J Chem Phys ; 134(1): 014508, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-21219008

RESUMEN

We investigated the frequency dependent dielectric relaxation behaviors of anhydrous trehalose and maltose glasses in the temperature range which covers a supercooled and glassy states. In addition to the α-, Johari-Goldstein (JG) ß-, and γ-relaxations in a typical glass forming system, we observed an extra relaxation process between JG ß- and γ-relaxations in the dielectric loss spectra. We found that the unknown extra relaxation is a unique property of disaccharide which might originate from the intramolecular motion of flexible glycosidic bond. We also found that the temperature dependence of the JG ß-relaxation time changes at 0.95T(g) and it might be universal.


Asunto(s)
Maltosa/química , Trehalosa/química , Vidrio/química , Temperatura
12.
Front Microbiol ; 12: 672661, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34248880

RESUMEN

Saccharomycopsis fibuligera is an amylolytic yeast that plays an important role within nuruk (a traditional Korean fermentation starter) used for the production of makgeolli (Korean rice wine), which is characterized by high acidity. However, the effect of pH change (neutral to acidic) on the yeast cell to hyphal transition and carbohydrate-hydrolyzing enzyme activities for S. fibuligera has not been investigated yet. In this study, S. fibuligera strains were cultured under the different pH conditions, and the effect on the enzyme production and gene expression were investigated. An acidic pH induced a hyphal transition from yeast cell of S. fibuligera KPH12 and the hybrid strain KJJ81. In addition, both strains showed a gradual decrease in the ability to degrade starch and cellulose as the pH went down. Furthermore, a transcriptome analysis demonstrated that the pH decline caused global expression changes in genes, which were classified into five clusters. Among the differentially expressed genes (DEGs) under acidic pH, the downregulated genes were involved in protein synthesis, carbon metabolism, and RIM101 and cAMP-PKA signaling transduction pathways for the yeast-hyphal transition. A decrease in pH induced a dimorphic lifestyle switch from yeast cell formation to hyphal growth in S. fibuligera and caused a decrease in carbohydrate hydrolyzing enzyme production, as well as marked changes in the expression of genes related to enzyme production and pH adaptation. This study will help to elucidate the mechanism of adaptation of S. fibuligera to acidification that occur during the fermentation process of makgeolli using nuruk.

13.
Foods ; 10(2)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671190

RESUMEN

With the increase in soybean trade between countries, the intentional mislabeling of the origin of soybeans has become a serious problem worldwide. In this study, metabolic profiling of soybeans from the Republic of Korea and China was performed by nuclear magnetic resonance (NMR) spectroscopy coupled with multivariate statistical analysis to predict the geographical origin of soybeans. The optimal orthogonal partial least squares-discriminant analysis (OPLS-DA) model was obtained using total area normalization and unit variance (UV) scaling, without applying the variable influences on projection (VIP) cut-off value, resulting in 96.9% sensitivity, 94.4% specificity, and 95.6% accuracy in the leave-one-out cross validation (LOO-CV) test for discriminating between Korean and Chinese soybeans. Soybeans from the northeastern, middle, and southern regions of China were successfully differentiated by standardized area normalization and UV scaling with a VIP cut-off value of 1.0, resulting in 100% sensitivity, 91.7%-100% specificity, and 94.4%-100% accuracy in a LOO-CV test. The methods employed in this study can be used to obtain essential information for the authentication of soybean samples from diverse geographical locations in future studies.

14.
Foods ; 10(4)2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33810579

RESUMEN

The precise determination of the chemical composition in crops is important to identify their nutritional and functional value. The current study performed a systematic delineation of the rice metabolome, an important staple in Asia, to investigate the following: (1) comparative features between brown and white rice; (2) variety-specific composition (Ilpum vs. Odae); and (3) cultivation of region-dependent metabolic content. Global metabolic profiling and data-driven statistics identified the exclusive enrichment of compounds in brown rice compared to white rice. Next, the authors investigated a variety-governed metabolic phenotype among various geo-environmental factors. Odae, the early-ripening cultivar, showed higher contents of most chemicals compared to the late-ripening cultivar, Ilpum. The authors identified regional specificity for cultivation among five areas in Korea which were characterized by polishing degree and cultivar type. Finally, the current study proposes a possible linkage of the region-specific metabolic signatures to soil texture and total rainfall. In addition, we found tryptophan metabolites that implied the potential for microbe-host interactions that may influence crop metabolites.

15.
J Microbiol ; 59(6): 598-608, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34052992

RESUMEN

Aroma ester components produced by fermenting yeast cells via alcohol acetyltransferase (AATase)-catalyzed intracellular reactions are responsible for the fruity character of fermented alcoholic beverages, such as beer and wine. Acetate esters are reportedly produced at relatively high concentrations by non-Saccharomyces species. Here, we identified 12 ATF orthologues (SfATFs) encoding putative AATases, in the diploid genome of Saccharomycopsis fibuligera KJJ81, an isolate from wheat-based Nuruk in Korea. The identified SfATF proteins (SfAtfp) display low sequence identities with S. cerevisiae Atf1p (between 13.3 and 27.0%). All SfAtfp identified, except SfAtf(A)4p and SfAtf(B)4p, contained the activation domain (HXXXD) conserved in other Atf proteins. Culture supernatant analysis using headspace gas chromatography mass spectrometry confirmed that the recombinant S. cerevisiae strains expressing SfAtf(A)2p, SfAtf(B)2p, and SfAtf(B)6p produced high levels of isoamyl and phenethyl acetates. The volatile aroma profiles generated by the SfAtf proteins were distinctive from that of S. cerevisiae Atf1p, implying difference in the substrate preference. Cellular localization analysis using GFP fusion revealed the localization of SfAtf proteins proximal to the lipid particles, consistent with the presence of amphipathic helices at their N- and C-termini. This is the first report that systematically characterizes the S. fibuligera ATF genes encoding functional AATases responsible for acetate ester formation using higher alcohols as substrate, demonstrating their biotechnological potential for volatile ester production.


Asunto(s)
Acetatos/metabolismo , Ésteres/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas/metabolismo , Saccharomycopsis/enzimología , Secuencia de Aminoácidos , Fermentación , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Dominios Proteicos , Estructura Secundaria de Proteína , Proteínas/química , Proteínas/genética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomycopsis/química , Saccharomycopsis/genética , Saccharomycopsis/metabolismo , Alineación de Secuencia , Vino/análisis , Vino/microbiología
16.
Food Res Int ; 143: 110271, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33992372

RESUMEN

Sesame (Sesamum indicum) is one of the most widely cultivated crops in Asia and Africa. The identification of the geographical origins of sesame seeds is important for the detection of fraudulent samples. This study was conducted to build a prediction model and suggest potential biomarkers for distinguishing the geographical origins of sesame seeds using mycobiome (fungal microbiome) analysis coupled with multivariate statistical analysis. Sesame seeds were collected from 25 cities in Korea, six cities in China, and five sites in other countries (Ethiopia, India, Nigeria, and Pakistan). According to the expression of fungal internal transcribed spacer (ITS) sequences in sesame seeds, 21 fungal genera were identified in sesame seeds from various countries. The optimal partial least squares-discriminant analysis model was established by applying two components with unit variance scaling. Based on seven-fold cross validation, the predictive model had 94.4% (Korea vs. China/other countries), 91.7% (China vs. Korea/other countries), and 88.9% (other countries vs. Korea/China) accuracy in determining the geographical origins of sesame seeds. Alternaria, Aspergillus, and Macrophomina were suggested as the potential fungal genera to differentiate the geographical origins of sesame seeds. This study demonstrated that mycobiome analysis could be used as a complementary method for distinguishing the geographical origins of raw sesame seeds.


Asunto(s)
Micobioma , Sesamum , China , Etiopía , India , Nigeria , Pakistán , República de Corea , Semillas
17.
Korean J Gastroenterol ; 56(1): 33-8, 2010 Jul.
Artículo en Coreano | MEDLINE | ID: mdl-20664316

RESUMEN

BACKGROUND/AIMS: The standard treatment for chronic hepatitis C infected with hepatitis C virus (HCV) genotype 1 is a combination of pegylated interferon alfa and ribavirin over a 48 weeks period. It is unclear if 24 weeks treatment is possible for patients showing a rapid virological response (RVR) without compromising the sustained virological response (SVR) in Korea. METHODS: Between June 2005 and September 2008, among patients chronically infected with the HCV genotype 1 who were treated with pegylated interferon alfa subcutaneously once weekly plus ribavirin based on body weight, 55 patients who had low pretreatment viral load (<600,000 IU/mL) and RVR were enrolled. A total of 55 patients were divided into 24 weeks treatment group (n=29) and the standard treatment group (n=26). The HCV RNA was quantitatively assessed before treatment, and after 12 weeks of treatment, and also qualitatively assessed after 4 weeks of treatment, at end of treatment (24 weeks), and 24 weeks after end of treatment. RVR was defined as undetectable HCV RNA at the 4 weeks of treatment. RESULTS: Among the 55 patients, SVR was achieved in 100% (29/29) of the patients in 24 weeks treatment and 96.2% (25/26) of the patients in the standard treatment (p=0.473). CONCLUSIONS: HCV genotype 1 infected patients with a low baseline HCV RNA concentration who become HCV RNA negative at week 4 may be treated for 24 weeks without compromising sustained virological response. However, an additional trial will be needed to optimize the treatment duration.


Asunto(s)
Antivirales/administración & dosificación , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/administración & dosificación , Polietilenglicoles/administración & dosificación , Ribavirina/administración & dosificación , Adulto , Anciano , Esquema de Medicación , Quimioterapia Combinada , Femenino , Genotipo , Humanos , Interferón alfa-2 , Masculino , Persona de Mediana Edad , ARN Viral/sangre , Proteínas Recombinantes , Carga Viral , Viremia/diagnóstico
18.
Korean J Gastroenterol ; 54(3): 191-5, 2009 Sep.
Artículo en Coreano | MEDLINE | ID: mdl-19844157

RESUMEN

Primary non-Hodgkin's lymphoma of the extrahepatic bile duct presenting as obstructive jaundice is extremely rare. A 60-year-old man was admitted due to suddenly developed jaundice. Computerized tomography and endoscopic retrograde cholangiopancreatography showed a tumor at the proximal common hepatic duct. These clinical and radiologic findings resembled those of Klatskin tumor. The resection of the common hepatic duct tumor, lymph node dissection, and Roux-en-Y hepaticojejunostomy were carried out. There was no regional lymph node metastasis and no residual tumor at the resection margins. Histology and immunohistochemistry of the resected specimen confirmed a diffuse large B-cell malignant lymphoma involving the common hepatic duct. The patient is scheduled to receive adjuvant chemotherapy. In summary, primary non-Hodgkins lymphoma of the extrahepatic bile duct, despite its rarity, should be considered in the differential diagnosis of causes for obstructive jaundice. An accurate histopathologic diagnosis and surgical resection combined with chemotherapy may be the approach to offer a chance for cure.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico , Linfoma de Células B Grandes Difuso/diagnóstico , Antígenos CD20/metabolismo , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/cirugía , Pancreatocolangiografía por Resonancia Magnética , Diagnóstico Diferencial , Humanos , Tumor de Klatskin/diagnóstico , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células B Grandes Difuso/cirugía , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
19.
Int J Food Microbiol ; 307: 108270, 2019 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-31408740

RESUMEN

Aspergillus oryzae is an important microbial starter for making diverse fermented foods due to its high hydrolytic enzyme activities. In this study, two strains of A. oryzae (AOB/AOK) with different activities of hydrolytic enzymes, such as α-amylase, protease and lipase, were cultured under various conditions of temperature, fermentation time, and initial pH. Comparative mass spectrometry (MS) based metabolomic analysis was performed to obtain primary metabolites and secondary volatile metabolite data sets. In the results of partial least square-discriminant analysis (PLS-DA), fatty acids and volatile metabolites derived from fatty acids and amino acids mainly contributed to AOK with higher protease and lipase activities, whereas carbohydrate-derived volatiles, sugars and sugar alcohols were related to main metabolites of AOB with higher α-amylase activity. The temperature and initial pH were critical factors for the generation of primary metabolites and secondary volatile metabolites, such as organic acids, fatty acids-derived volatiles, and some amino acids, in both A. oryzae strains. This study demonstrated that the specific culture conditions were closely linked to the formation of primary metabolites and secondary volatile metabolites of A. oryzae.


Asunto(s)
Aspergillus oryzae/metabolismo , Alimentos Fermentados/microbiología , Metabolómica , Aspergillus oryzae/enzimología , Fermentación , Concentración de Iones de Hidrógeno , Lipasa/metabolismo , Compuestos Orgánicos/análisis , Compuestos Orgánicos/metabolismo , Péptido Hidrolasas/metabolismo , Temperatura , alfa-Amilasas/metabolismo
20.
Front Microbiol ; 10: 2326, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31681199

RESUMEN

Arsenite-resistance protein 2 (Ars2) is an important nuclear protein involved in various RNA metabolisms in animals and plants, but no Ars2 ortholog has been studied in filamentous fungi. Although it is an essential gene in most model eukaryotes, FgARS2 null mutants were viable in the plant pathogenic fungus Fusarium graminearum. The deletion of FgARS2 resulted in pleiotropic defects in various fungal developmental processes. Fgars2 mutants were irregular in nuclear division, and conidial germination was significantly retarded, causing the fungus to manifest its hypersensitive phenotypes under DNA damage stress. While FgARS2 deletion caused abnormal morphologies of ascospores and defective ascospore discharge, our data revealed that FgARS2 was not closely involved in small-non-coding RNA production in F. graminearum. The dominant nuclear localization of FgArs2-green fluorescent proteins (GFP) and abnormal nuclear division in FgARS2 deletion mutant implicated that FgArs2 functions in the nucleus. Intriguingly, we found that FgArs2 established a robust physical interaction with the cap binding complex (CBC) to form a tertiary complex CBC-Ars2 (CBCA), and disruption of any CBCA complex subunit drastically attenuated the virulence of F. graminearum. The results of the study indicate that Ars2 regulates fungal development, stress response, and pathogenesis via interaction with CBC in F. graminearum and provide a novel insight into understanding of the biological functions of Ars2 in filamentous fungi.

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