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1.
Stroke ; 53(3): 698-709, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34781708

RESUMEN

BACKGROUND AND PURPOSE: Cerebral small vessel disease is characterized by progressive cerebral white matter changes (WMCs). This study aimed to compare the effects of cilostazol and aspirin on changes in WMC volume in patients with cerebral small vessel disease. METHODS: In a multicenter, double-blind, randomized controlled trial, participants with moderate or severe WMCs and at least one lacunar infarction detected on brain magnetic resonance imaging were randomly assigned to the cilostazol and aspirin groups in a 1:1 ratio. Cilostazol slow release (200 mg) or aspirin (100 mg) capsules were administered once daily for 2 years. The primary outcome was the change in WMC volume on magnetic resonance images from baseline to 2 years. Secondary imaging outcomes include changes in the number of lacunes or cerebral microbleeds, fractional anisotropy, and mean diffusivity on diffusion tensor images, and brain atrophy. Secondary clinical outcomes include all ischemic strokes, all ischemic vascular events, and changes in cognition, motor function, mood, urinary symptoms, and disability. RESULTS: Between July 2013 and August 2016, 256 participants were randomly assigned to the cilostazol (n=127) and aspirin (n=129) groups. Over 2 years, the percentage of WMC volume to total WM volume and the percentage of WMC volume to intracranial volume increased in both groups, but neither analysis showed significant differences between the groups. The peak height of the mean diffusivity histogram in normal-appearing WMs was significantly reduced in the aspirin group compared with the cilostazol group. Cilostazol significantly reduced the risk of ischemic vascular event compared with aspirin (0.5 versus 4.5 cases per 100 person-years; hazard ratio, 0.11 [95% CI, 0.02-0.89]). CONCLUSIONS: There was no significant difference between the effects of cilostazol and aspirin on WMC progression in patients with cerebral small vessel disease. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01932203.


Asunto(s)
Aspirina/administración & dosificación , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/tratamiento farmacológico , Cilostazol/administración & dosificación , Imagen por Resonancia Magnética , Sustancia Blanca , Anciano , Anciano de 80 o más Años , Aspirina/efectos adversos , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/etiología , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Cilostazol/efectos adversos , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sustancia Blanca/irrigación sanguínea , Sustancia Blanca/diagnóstico por imagen
2.
Int J Mol Sci ; 22(7)2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33917505

RESUMEN

The APSES family proteins are transcription factors (TFs) with a basic helix-loop-helix domain, known to regulate growth, development, secondary metabolism, and other biological processes in Aspergillus species. In the genome of the human opportunistic pathogenic fungus Aspergillus fumigatus, five genes predicted to encode APSES TFs are present. Here, we report the characterization of one of these genes, called mbsA (Afu7g05620). The deletion (Δ) of mbsA resulted in significantly decreased hyphal growth and asexual sporulation (conidiation), and lowered mRNA levels of the key conidiation genes abaA, brlA, and wetA. Moreover, ΔmbsA resulted in reduced spore germination rates, elevated sensitivity toward Nikkomycin Z, and significantly lowered transcripts levels of genes associated with chitin synthesis. The mbsA deletion also resulted in significantly reduced levels of proteins and transcripts of genes associated with the SakA MAP kinase pathway. Importantly, the cell wall hydrophobicity and architecture of the ΔmbsA asexual spores (conidia) were altered, notably lacking the rodlet layer on the surface of the ΔmbsA conidium. Comparative transcriptomic analyses revealed that the ΔmbsA mutant showed higher mRNA levels of gliotoxin (GT) biosynthetic genes, which was corroborated by elevated levels of GT production in the mutant. While the ΔmbsA mutant produced higher amount of GT, ΔmbsA strains showed reduced virulence in the murine model, likely due to the defective spore integrity. In summary, the putative APSES TF MbsA plays a multiple role in governing growth, development, spore wall architecture, GT production, and virulence, which may be associated with the attenuated SakA signaling pathway.


Asunto(s)
Aspergillus fumigatus/metabolismo , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Esporas Fúngicas/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética , Aspergillus fumigatus/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Esporas Fúngicas/genética , Factores de Transcripción/genética
3.
Health Care Manag Sci ; 23(4): 585-604, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32770444

RESUMEN

South Korea's large hospitals are severely burdened by patient congestion because patients throng to these places expecting to get treated better given their higher-quality healthcare. Effective cost management of the healthcare system is one way to reduce patient congestion in a large hospital. This study proposes methods that can help direct patient flows in a desirable direction and suggests ways to effectively manage the cost of healthcare. The study also discusses how selfish patients act in ways that maximize their benefits by choosing a specific hospital and in turn forcing the hospital and the healthcare network to bear more costs than is necessary. The study proposes a model describing the need for intervention from the government to control the cost escalation resulting from selfish routing. The study proposes two heuristic algorithms to solve the suggested model. The flow-based algorithm addresses the target quantum of flows, and the utility-based algorithm targets the value of cost functions. Performances of heuristics are evaluated through numerical experiments. The utility-based algorithm yields higher values for objectives, while the flow-based algorithm controls the extent of investment. A case study based on data from the Seoul city database is also analyzed. The cost adjustment policy is compared with simple, uniformly improved network policies, and findings show that such policies have the strength needed to improve the cost-effectiveness of the healthcare system if implemented fully and effectively.


Asunto(s)
Análisis Costo-Beneficio , Costos y Análisis de Costo , Atención a la Salud/organización & administración , Economía Hospitalaria , Algoritmos , Conducta de Elección , Atención a la Salud/economía , Atención a la Salud/estadística & datos numéricos , Heurística , Hospitales/normas , Humanos , Estudios de Casos Organizacionales , República de Corea
4.
Thin Solid Films ; 692: 137637, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-32287450

RESUMEN

[(Nix Mn 1- x )0.84Cu 0.16]3O4 (0.20 ≤ x ≤ 0.40) thin films have been prepared using the metal-organic decomposition method for microbolometer applications. Spinel thin films with a thickness of approximately 100 nm were obtained from the [(Ni x Mn1- x )0.84Cu0.16]3O4 films annealed at the low temperature of 380 °C for 5 h, which enables their direct integration onto substrates having complementary metal-oxide-semiconductor (CMOS) read-out circuitry. To obtain negative-temperature-coefficient films with reasonable performance through low enough temperature anneal process, Ni content has been systematically varied, and the film microstructure has been found to depend on the relative amount of Ni and Mn. A single phase of cubic spinel structure has been confirmed in the prepared films. The resistivity (ρ) of the annealed films decreases with increasing Mn4+/Mn3+ value due to the hopping mechanism between Mn3+ and Mn4+ cations in octahedral sites of spinel structure. Although the temperature coefficient of resistance (TCR) of the annealed films has been decreased slightly with the increase of Ni content, good enough properties of the film (ρ = 61.3 Ω•cm, TCR = -2.950%/K in x = 0.30 film) has been obtained even with the annealing at rather low temperature of 380 °C, thus enabling the direct integration onto substrates having read-out circuitry. The results obtained in this work are promising for applications to CMOS integrated microbolometer devices.

5.
Int J Mol Sci ; 20(22)2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31717953

RESUMEN

The regulator of G-protein signaling (RGS) proteins play an important role in upstream control of heterotrimeric G-protein signaling pathways. In the genome of the human opportunistic pathogenic fungus Aspergillus fumigatus, six RGS protein-encoding genes are present. To characterize the rgsA gene predicted to encode a protein with an RGS domain, we generated an rgsA null mutant and observed the phenotypes of the mutant. The deletion (Δ) of rgsA resulted in increased radial growth and enhanced asexual sporulation in both solid and liquid culture conditions. Accordingly, transcripts levels of the key asexual developmental regulators abaA, brlA, and wetA are elevated in the ΔrgsA mutant. Moreover, ΔrgsA resulted in elevated spore germination rates in the absence of a carbon source. The activity of cAMP-dependent protein kinase A (PKA) and mRNA levels of genes encoding PKA signaling elements are elevated by ΔrgsA. In addition, mRNA levels of genes associated with stress-response signaling increased with the lack of rgsA, and the ΔrgsA spores showed enhanced tolerance against oxidative stressors. Comparative transcriptomic analyses revealed that the ΔrgsA mutant showed higher mRNA levels of gliotoxin (GT) biosynthetic genes. Accordingly, the rgsA null mutant exhibited increased production of GT and elevated virulence in the mouse. Conversely, the majority of genes encoding glucan degrading enzymes were down-regulated by ΔrgsA, and endoglucanase activities were reduced. In summary, RgsA plays multiple roles, governing growth, development, stress responses, virulence, and external polymer degradation-likely by attenuating PKA signaling.


Asunto(s)
Aspergilosis/microbiología , Aspergillus fumigatus/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas Fúngicas/metabolismo , Estrés Oxidativo , Proteínas RGS/metabolismo , Animales , Aspergillus fumigatus/genética , Aspergillus fumigatus/patogenicidad , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Femenino , Proteínas Fúngicas/genética , Gliotoxina/biosíntesis , Ratones , Ratones Endogámicos ICR , Proteínas RGS/genética , Transducción de Señal , Transcriptoma , Virulencia/genética
6.
J Environ Sci Health B ; 53(2): 135-140, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29173073

RESUMEN

As an alternative to synthetic pesticides, natural materials such as plant extracts and microbes have been considered to control plant diseases. In this study, methanol extracts of 120 plants were explored for in vivo antifungal activity against Rhizoctonia solani, Botrytis cinerea, Phytophthora infestans, Puccinia triticina, and Blumeria graminis f. sp. hordei. Of the 120 plant extracts, eight plant extracts exhibited a disease control efficacy of more than 90% against at least one of five plant diseases. In particular, a methanol extract of Curcuma zedoaria rhizomes exhibited strong activity against wheat leaf rust caused by P. triticina. When the C. zedoaria methanol extracts were partitioned with various solvents, the layers of n-hexane, methylene chloride, and ethyl acetate showed disease control values of 100, 80, and 43%, respectively, against wheat leaf rust. From the C. zedoaria rhizome extracts, an antifungal substance was isolated and identified as a sesquiterpene ketolactone based on the mass and nuclear magnetic resonance spectral data. The active compound controlled the development of rice sheath blight, wheat leaf rust, and tomato late blight. Considering the in vivo antifungal activities of the sesquiterpene ketolactone and the C. zedoaria extracts, these results suggest that C. zedoaria can be used as a potent fungicide in organic agriculture.


Asunto(s)
Curcuma/química , Fungicidas Industriales/farmacología , Lactonas/farmacología , Enfermedades de las Plantas/prevención & control , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Acetatos/química , Basidiomycota/efectos de los fármacos , Basidiomycota/patogenicidad , Fungicidas Industriales/química , Hexanos , Lactonas/química , Lactonas/aislamiento & purificación , Solanum lycopersicum/microbiología , Metanol/química , Estructura Molecular , Agricultura Orgánica/métodos , Oryza/microbiología , Extractos Vegetales/química , Rhizoctonia/efectos de los fármacos , Rhizoctonia/patogenicidad , Rizoma/química , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Solventes/química , Triticum/microbiología
7.
Int J Med Sci ; 14(13): 1418-1429, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29200956

RESUMEN

We previously described a novel tissue cryopreservation protocol to enable the safe preservation of various autologous stem cell sources. The present study characterized the stem cells derived from long-term cryopreserved dental pulp tissues (hDPSCs-cryo) and analyzed their differentiation into definitive endoderm (DE) and hepatocyte-like cells (HLCs) in vitro. Human dental pulp tissues from extracted wisdom teeth were cryopreserved as per a slow freezing tissue cryopreservation protocol for at least a year. Characteristics of hDPSCs-cryo were compared to those of stem cells from fresh dental pulps (hDPSCs-fresh). hDPSCs-cryo were differentiated into DE cells in vitro with Activin A as per the Wnt3a protocol for 6 days. These cells were further differentiated into HLCs in the presence of growth factors until day 30. hDPSCs-fresh and hDPSCs-cryo displayed similar cell growth morphology, cell proliferation rates, and mesenchymal stem cell character. During differentiation into DE and HLCs in vitro, the cells flattened and became polygonal in shape, and finally adopted a hepatocyte-like shape. The differentiated DE cells at day 6 and HLCs at day 30 displayed significantly increased DE- and hepatocyte-specific markers at the mRNA and protein level, respectively. In addition, the differentiated HLCs showed detoxification and glycogen storage capacities, indicating they could share multiple functions with real hepatocytes. These data conclusively show that hPDSCs-cryo derived from long-term cryopreserved dental pulp tissues can be successfully differentiated into DE and functional hepatocytes in vitro. Thus, preservation of dental tissues could provide a valuable source of autologous stem cells for tissue engineering.


Asunto(s)
Diferenciación Celular/genética , Endodermo/citología , Hepatocitos/citología , Células Madre Mesenquimatosas/citología , Proliferación Celular/genética , Criopreservación , Pulpa Dental/citología , Endodermo/metabolismo , Glucógeno/metabolismo , Hepatocitos/metabolismo , Humanos , Células Madre Mesenquimatosas/metabolismo , Ingeniería de Tejidos
8.
Pestic Biochem Physiol ; 141: 103-108, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28911735

RESUMEN

The in vivo antifungal activity of crude extracts of Dipsacus asper roots was evaluated against the phytopathogenic fungi Botrytis cinerea, Colletotrichum coccodes, Blumeria graminis f. sp. hordei, Magnaporthe grisea, Phytophthora infestans, Puccinia recondita and Rhizoctonia solani using a whole-plant assay method. Ethyl acetate and acetone extracts, at 1000µg/mL, suppressed the development of tomato gray mold (TGM) and tomato late blight (TLB) by 90%. Through bioassay-guided isolation, five antifungal substances were isolated from the D. asper roots and identified as ß-sitosterol (1), campesterol (2), stigmasterol (3), cauloside A (4) and a novel dipsacus saponin, named colchiside (3-O-ß-d-xylopyranosyl-23-O-ß-d-glucopyranosyl-28-O-ß-d-(6-O-acetyl)-glucopyranosyl hederagenin) (5). Of those, cauloside A (4) displayed the greatest antifungal efficacy against rice blast, TGM and TLB. Colchiside (5) moderately suppressed the development of TLB, but exhibited little effect against the other diseases. The synergistic effects of the isolated compounds against TLB were also assessed. Synergistic and additive interactions were observed between several of the sterol compounds. This study indicated that the crude extracts of, and bioactive substances from, the roots of D. asper suppress TGM and TLB. In addition, cauloside A (4) and colchiside (5) could be used as antifungal lead compounds.


Asunto(s)
Antifúngicos/farmacología , Dipsacaceae/efectos de los fármacos , Dipsacaceae/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Saponinas/metabolismo , Esteroles/farmacología , Colesterol/análogos & derivados , Colesterol/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Fitosteroles/metabolismo , Sitoesteroles/metabolismo
9.
Phytother Res ; 28(9): 1335-41, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24623672

RESUMEN

Meju, a naturally fermented soy block used to produce soy paste and soy sauce in Korea, is suggested to exhibit hypolipidemic and antiinflammatory activities; however, its mechanisms of action are elusive. Here, we report that the water-soluble fibers but not the amino acids and peptides from meju exhibited hypolipidemic activity in vivo. Feeding of fermented soybean fibers (FSF) from meju reduced plasma cholesterol, triglyceride, adipocyte size, and hepatic lipid accumulation in C57BL/6 J mice. FSF treatment reduced HMG-CoA reductase expression, whereas the expression of genes in the fatty acid uptake and subsequent beta-oxidation were significantly induced in the livers. Hepatic lipogenic genes, including Srebp1c and Lxrα, were unaltered. Feeding with the fermented soybean peptides and amino acids (FSPA) induced the expression of lipogenic genes, which may have canceled the induction of low-density lipoprotein receptor and Cyp7a1 gene expressions in FSPA livers. The plasma concentrations of C-reactive protein, TNF-α, and interlukin-6 were significantly reduced in the FSF, FSPA, and meju groups compared with the control groups, suggesting that both of the fibers and peptides/amino acids from meju may be beneficial. These findings suggest that soluble fibers from meju are critical hypolipidemic components that regulate hepatic gene expressions and reduce proinflammatory cytokines in vivo.


Asunto(s)
Antiinflamatorios/farmacología , Fibras de la Dieta/farmacología , Fermentación , Glycine max/química , Hipolipemiantes/farmacología , Animales , Citocinas/sangre , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Proteínas de Soja/farmacología
10.
Environ Monit Assess ; 186(5): 2949-56, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24374805

RESUMEN

The dose rates for six marine organisms, pelagic fish, benthic fish, mollusks, crustaceans, macroalgae, and polychaete worms, representative in marine ecosystems, have been predicted by the equilibrium model with the measured seawater activity concentrations at three locations around the Fukushima Daiich nuclear power plant after the accident on March 11, 2011. Model prediction showed that total dose rates for the biota in the costal sea reached 4.8E4 µGy/d for pelagic fish, 3.6E6 µGy/d for crustaceans, 3.8E6 µGy/d for benthic fish, 5.2E6 µGy/d for macroalgae, 6.6E6 µGy/d for mollusks, and 8.0E6 µGy/d for polychaete worms. The predicted total dose rates remained above the UNSCEAR's (United Nations Scientific Committee on the Effect of Atomic Radiation) benchmark level (1.0E4 µGy/d for an individual aquatic organism), for only the initial short period, which seems to be insufficiently long to bring about any detrimental effect on the marine biota at the population level. Furthermore, the total dose rates for benthic fish and crustaceans approximated using the measured activity concentration of the biota and bottom sediment was well below the benchmark level. From these results, it may be concluded that the impact of the ionizing radiation on the marine biota around the Fukushima NPP as a consequence of the accident would be insignificant.


Asunto(s)
Organismos Acuáticos/metabolismo , Accidente Nuclear de Fukushima , Monitoreo de Radiación , Contaminantes Radiactivos del Agua/análisis , Animales , Biota , Ecosistema , Plantas de Energía Nuclear , Agua de Mar/química , Contaminantes Radiactivos del Agua/metabolismo
11.
Mar Environ Res ; 196: 106439, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38479292

RESUMEN

In semi-enclosed coastal brackish lakes, changes in dissolved oxygen in the bottom layer due to salinity stratification can affect the flux of phosphorus (P) at the sediment-water interface, resulting in short- and long-term water quality fluctuations in the water column. In this study, the physicochemical properties of the water layers and sediments at five sites in Saemangeum Lake were analyzed in spring and autumn for four years, and phosphorus release experiments from sediments were conducted for 20 days under oxic and anoxic conditions during the same period. Sediment total phosphorus (T-P) decreased in autumn compared to spring due to mineralization of organic bound phosphorus, which was the most dominant P fraction. This may be related to the increase in the ratio of PO4-P to T-P in bottom waters in autumn, when hypoxia was frequently observed. The difference in P fluxes between oxic and anoxic conditions indicated that during autumn, as compared to spring, the release of phosphorus could have a more immediate impact on the water column during the formation of hypoxia/anoxia. The main factors influencing changes in P fluxes from sediments were identified through redundancy analysis. Additionally, based on the results of multiple regression analysis, sediment TOC, sediment non-apatite phosphorus, porewater pH, and porewater PO4-P were determined to be the most significant factors affecting P fluxes from sediments, depending on the season or redox conditions. Recently, the increased influx of seawater into Saemangeum Lake has been shown to contribute to water quality improvements in the water column due to a strong dilution effect. However, the sediment environment has shifted towards a more reduced state, leading to increased P release under anoxic conditions. Therefore, for future water quality management within the lake, it is necessary to consistently address the recurring hypoxia and continuously monitor phosphorus dynamics.


Asunto(s)
Lagos , Contaminantes Químicos del Agua , Humanos , Lagos/química , Fósforo/análisis , Oxígeno , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Hipoxia , China
12.
Biosens Bioelectron ; 247: 115932, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38113695

RESUMEN

Early detection and effective blood glucose control are critical for preventing and managing diabetes-related complications. Conventional glucometers provide point-in-time measurements but are painful and cannot facilitate continuous monitoring. Continuous glucose monitoring systems are comfortable but face challenges in terms of accuracy, cost, and sensor lifespan. This study aimed to develop a microneedle-based sensor patch for minimally invasive, painless, and continuous glucose monitoring in the interstitial fluid to address these limitations. Experimental results confirm painless and minimally invasive penetration of the skin tissue with cylindrical microneedles (3 × 3 array) to a depth of approximately 520 µm with minimal loading. The microneedle sensors fabricated with precision using the complementary metal-oxide semiconductor process were immobilized with glucose oxidase, as confirmed through phase angle analysis. Long-term tests confirmed the effective operation of the sensor for up to seven days. Glucose concentrations determined from the fitted concentration-impedance curves correlated well with those measured using commercial glucometers, indicating the reliability and precision of the microneedle sensor. The flexible and minimally invasive sensor developed in this study facilitates painless and continuous glucose monitoring.


Asunto(s)
Técnicas Biosensibles , Automonitorización de la Glucosa Sanguínea , Glucemia , Polímeros , Líquido Extracelular/química , Impedancia Eléctrica , Reproducibilidad de los Resultados , Agujas , Glucosa/análisis
13.
Chemosphere ; 357: 141961, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615954

RESUMEN

Microplastics (MPs) poses a significant threat to ecosystems and human health, demanding immediate attention. The reported research work offers an effective and low cost method towards the detection of toxic MPs. In this study, hydrophobic cerium oxide nanoparticles (CeO2 NPs) are synthesized and applied as promising electrode material for the detection of two different types of MPs, i.e. polyethylene (PE) and polypropylene (PP). Through electrochemical analyses, such as cyclic voltammetry (CV) and linear sweep voltammetry (LSV), hydrophobic CeO2 NPs modified glassy carbon electrode (GCE) based sensor demonstrated remarkable sensitivity of ∼0.0343 AmLmg-1cm-2 and detection limit of ∼0.226 mgmL-1, with promising correlation coefficient (R2) towards the detection of PE (∼27-32 µm). Furthermore, hydrophobic CeO2 NPs modified GCE exhibited promising stability and reproducibility towards PE (∼27-32 µm), suggesting the promising potential of hydrophobic CeO2 NPs as electrode materials for an electrochemical microplastics detection.


Asunto(s)
Cerio , Monitoreo del Ambiente , Interacciones Hidrofóbicas e Hidrofílicas , Microplásticos , Contaminantes Químicos del Agua , Cerio/química , Contaminantes Químicos del Agua/análisis , Microplásticos/análisis , Monitoreo del Ambiente/métodos , Nanopartículas/química , Técnicas Electroquímicas/métodos , Electrodos , Polietileno/química , Reproducibilidad de los Resultados , Nanopartículas del Metal/química , Polipropilenos/química , Límite de Detección
14.
J Microbiol Biotechnol ; 34(3): 654-662, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38213301

RESUMEN

To investigate the effect of the predominant fungal species from Korean traditional meju and doenjang on soybean fermentation, the enzymatic activity and amino acid production of twenty-two fungal strains were assessed through solid- and liquid-state soybean fermentation. Enzymatic activity analyses of solid-state fermented soybeans revealed different enzyme activities involving protease, leucine aminopeptidase (LAP), carboxypeptidase (CaP), glutaminase, γ-glutamyl transferase (GGT), and amylase, depending on the fungal species. These enzymatic activities significantly affected the amino acid profile throughout liquid-state fermentation. Strains belonging to Mucoromycota, including Lichtheimia, Mucor, Rhizomucor, and Rhizopus, produced smaller amounts of total amino acids and umami-producing amino acids, such as glutamic acid and aspartic acid, than strains belonging to Aspergillus subgenus circumdati. The genera Penicillium and Scopulariopsis produced large amounts of total amino acids and glutamic acid, suggesting that these genera play an essential role in producing umami and kokumi tastes in fermented soybean products. Strains belonging to Aspergillus subgenus circumdati, including A. oryzae, showed the highest amino acid content, including glutamic acid, suggesting the potential benefits of A. oryzae as a starter for soybean fermentation. This study showed the potential of traditional meju strains as starters for soybean fermentation. However, further analysis of processes such as the production of G-peptide for kokumi taste and volatile compounds for flavor and safety is needed.


Asunto(s)
Aminoácidos , Alimentos de Soja , Aminoácidos/metabolismo , Alimentos de Soja/microbiología , Glycine max , Fermentación , Hongos , Aspergillus/metabolismo , Ácido Glutámico/metabolismo , Péptido Hidrolasas/metabolismo
15.
Biosci Biotechnol Biochem ; 77(11): 2192-200, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24200796

RESUMEN

We compared the volatile profiles in soy sauce according to inoculation with Tetragenococcus halophilus and/or Zygosaccharomyces rouxii. Totals of 107 and 81 volatiles were respectively identified by using solid-phase microextraction and solvent extraction. The various volatile compounds identified included acids, aldehydes, esters, ketones, furans and furan derivatives, and phenols. The major volatiles in the samples treated with T. halophilus were acetic acid, formic acid, benzaldehyde, methyl acetate, ethyl 2-hydroxypropanoate, 2-hydroxy-3-methyl-2-cyclopenten-1-one, and 4-hydroxy-3-methoxybenzaldehyde, while those in the samples inoculated with Z. rouxii were mainly ethanol, acetaldehyde, ethyl propanoate, 2/3-methylbutanol, 1-butanol, 2-phenylethanol, ethyl 2-methylpropanoate, and 4-hydroxy-2-ethyl-5-methyl-3(2H)-furanone. The results indicate that T. halophilus produced significant acid compounds and could affect the Z. rouxii activity, supporting the notion that yeasts and lactic acid bacteria respectively have different metabolic pathways of alcoholic fermentation and lactic acid fermentation, and produce different dominant volatile compounds in soy sauce.


Asunto(s)
Enterococcaceae/metabolismo , Alimentos de Soja/microbiología , Compuestos Orgánicos Volátiles/análisis , Zygosaccharomyces/metabolismo , Alcoholes/análisis , Alcoholes/metabolismo , Aldehídos/análisis , Aldehídos/metabolismo , Ácidos Carboxílicos/análisis , Ácidos Carboxílicos/metabolismo , Fermentación , Furanos/análisis , Furanos/metabolismo , Redes y Vías Metabólicas , Fenoles/análisis , Fenoles/metabolismo , Microextracción en Fase Sólida , Solventes , Alimentos de Soja/análisis , Especificidad de la Especie , Terpenos/análisis , Terpenos/metabolismo , Compuestos Orgánicos Volátiles/metabolismo
16.
Plant Dis ; 97(12): 1593-1598, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30716836

RESUMEN

In the process of searching antibacterial agents from plants, we discovered that the methanol extract of Sedum takesimense showed potent antibacterial activity against Ralstonia solanacearum in vitro and in vivo. Eight antibacterial gallotannins were isolated from the aerial parts of S. takesimense and identified as gallic acid, methyl gallate, 4,6-di-O-galloylarbutin, 2,6-di-O-galloylarbutin, 2,4,6-tri-O-galloyl-glucose, 1,3,4,6-tetra-O-galloyl-ß-glucose, 1,2,4,6-tetra-O-galloyl-ß-glucose, and 1,2,3,6-tetra-O-galloyl-ß-glucose based on electrospray ionization mass spectrometry and proton nuclear magnetic resonance spectroscopy. These gallotannins displayed broad-spectrum activity against various plant-pathogenic bacteria, and the strongest in vitro antibacterial activities of these gallotannins were against R. solanacearum minimum inhibitory concentration = 0.02 to 0.10 g/liter). Among these gallotannins, methyl gallate and 1,2,3,6-tetra-O-galloyl-ß-glucose showed the strongest activities. In addition, synergistic or partial synergistic effects were observed in most combinations between major antibacterial compounds. The wettable powder formulation of the S. takesimense crude extract effectively reduced the development of tomato bacterial wilt caused by R. solanacearum under greenhouse conditions for 14 days after infection. This is the first report on the isolation of antibacterial compounds from S. takesimense. These results suggest that the extract from S. takesimense or the isolated gallotannins could be used as natural bactericides for the control of tomato bacterial wilt.

17.
Biotechnol Lett ; 34(12): 2235-40, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22932931

RESUMEN

D-lactic acid production from dry biomass of the microalga, Hydrodictyon reticulatum, was carried out in a 5-l jar fermentor (initial pH 6, 34 °C using CaCO(3) as a neutralizing agent) through simultaneous saccharification and co-fermentation using the Lactobacillus coryniformis subsp. torquens. After 36 h, 36.6 g lactic acid/l was produced from 80 g H. reticulatum/l in the medium containing 3 g yeast extract/l and 3 g peptone/l in the absence of mineral salts. The maximum productivity, average productivity and yield were 2.38 g/l h, 1.02 g/l h and 45.8 %, respectively. The optical purity of D-Lactic acid ranged from 95.8-99.6 %. H. reticulatum is thus a promising biomass material for the production of D-Lactic acid.


Asunto(s)
Chlorophyta/química , Ácido Láctico/metabolismo , Lactobacillus/metabolismo , Biomasa , Reactores Biológicos/microbiología , Carbonato de Calcio/metabolismo , Fermentación , Concentración de Iones de Hidrógeno , Lactobacillus/crecimiento & desarrollo , Temperatura
18.
J Fungi (Basel) ; 8(6)2022 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-35736073

RESUMEN

Histone demethylases govern diverse cellular processes, including growth, development, and secondary metabolism. In the present study, we investigated the functions of two lysine demethylases, KdmA and KdmB, in the opportunistic human pathogenic fungus Aspergillus fumigatus. Experiments with mutants harboring deletions of genes encoding KdmA (ΔkdmA) and KdmB (ΔkdmB) showed that KdmA is necessary for normal growth and proper conidiation, whereas KdmB negatively regulates vegetative growth and conidiation. In both mutant strains, tolerance to H2O2 was significantly decreased, and the activities of both conidia-specific catalase (CatA) and mycelia-specific catalase (Cat1) were decreased. Both mutants had significantly increased sensitivity to the guanine nucleotide synthesis inhibitor 6-azauracil (6AU). The ΔkdmA mutant produced more gliotoxin (GT), but the virulence was not changed significantly in immunocompromised mice. In contrast, the production of GT and virulence were markedly reduced by the loss of kdmB. Comparative transcriptomic analyses revealed that the expression levels of developmental process-related genes and antioxidant activity-related genes were downregulated in both mutants. Taken together, we concluded that KdmA and KdmB have opposite roles in vegetative growth, asexual sporulation, and GT production. However, the two proteins were equally important for the development of resistance to 6AU.

19.
Nanomaterials (Basel) ; 11(12)2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34947729

RESUMEN

Reusable, antibacterial, and photocatalytic isoporous through-hole air filtration membranes have been demonstrated based on hydrothermally grown ZnO nanorods (NRs). High-temperature (300~375 °C) stability of thermoset-based isoporous through-hole membranes has enabled concurrent control of porosity and seed formation via high-temperature annealing of the membranes. The following hydrothermal growth has led to densely populated ZnO NRs on both the membrane surface and pore sidewall. Thanks to the nanofibrous shape of the grown ZnO NRs on the pore sidewall, the membrane filters have shown a high (>97%) filtration efficiency for PM2.5 with a rather low-pressure (~80 Pa) drop. The membrane filters could easily be cleaned and reused many times by simple spray cleaning with a water/ethanol mixture solution. Further, the grown ZnO NRs have also endowed excellent bactericidal performance for both Gram-positive S. aureus and Gram-negative S. enteritidis bacteria. Owing to the wide bandgap semiconductor nature of ZnO NRs, organic decomposition by photocatalytic activity under UV illumination has been successfully demonstrated. The reusable, multifunctional membrane filters can find wide applications in air filtration and purification.

20.
Neonatology ; 118(1): 37-46, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33503618

RESUMEN

BACKGROUND: The infant brain grows quickly with elaborate microstructural development during the neonatal period. The white matter, during critical periods of development, is selectively vulnerable to altered maturation and impaired growth in very-low-birth-weight (VLBW) infants. OBJECTIVE: To evaluate whether abnormal white matter maturation in VLBW infants is associated with poor neurodevelopmental outcomes at 18 months of corrected age. METHODS: Between 2015 and 2017, we recruited 60 VLBW infants at 24-32 weeks of gestational age and 15 full-term controls. All participants underwent magnetic resonance imaging at near-term age and were assessed at 18 months of corrected age with the Bayley Scales of Infant and Toddler Development, Third Edition. The associations between regional white matter fractional anisotropy (FA) and mean diffusivity on diffusion tensor imaging (DTI) and developmental outcomes were explored using multivariable linear regression after correcting for gestational age, postmenstrual age at DTI scan, and maternal education level. RESULTS: The FA values of the splenium of the corpus callosum (p = 0.032), corticospinal tract (p = 0.025), middle cerebellar peduncle (MCP) (p < 0.001), and cingulum (p = 0.043) were significantly related to cognitive scores; however, only the association corresponding to the MCP remained significant after correcting for multiple comparisons. The MCP FA (p = 0.008) was associated with motor scores after correction for multiple comparisons (p = 0.008). Cognitive impairment (area under the curve [AUC] = 0.823, 95% confidence interval [CI] = 0.722-0.911) and motor impairment (AUC = 0.776, 95% CI = 0.656-0.899) were predicted by MCP FA. CONCLUSIONS: The FA of MCP at near-term age may predict developmental outcomes of VLBW infants at 18 months of corrected age.


Asunto(s)
Pedúnculo Cerebeloso Medio , Sustancia Blanca , Adolescente , Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Sustancia Blanca/diagnóstico por imagen
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