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1.
J Fungi (Basel) ; 9(3)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36983507

RESUMO

In nature; Flammulina velutipes, also known as winter mushrooms, vary in the color of their fruiting bodies, from black, yellow, pale yellow, or beige to white. The purpose of this study was to compare the genome sequences of different colored strains of F. velutipes and to identify variations in the genes associated with fruiting body color. Comparative genomics of six F. velutipes strains revealed 70 white-strain-specific variations, including single nucleotide polymorphisms (SNPs) and insertions/deletions (indels), in the genome sequences. Among them, 36 variations were located in the open reading frames, and only one variation was identified as a mutation with a disruptive in-frame deletion (ΔGCGCAC) within the annotated gene phenylalanine ammonia-lyase 1 (Fvpal1). This mutation was found to cause a deletion, without a frameshift, of two amino acids at positions 112 and 113 (arginine and threonine, respectively) in the Fvpal1 gene of the white strain. Specific primers to detect this mutation were designed, and amplification refractory mutation system (ARMS) polymerase chain reaction (PCR) was performed to evaluate whether the mutation is color specific for the F. velutipes fruiting body. PCR analysis of a total of 95 F. velutipes strains revealed that this mutation was present only in white strains. In addition, monospores of the heterozygous mutant were isolated, and whether this mutation was related to the color of the fruiting body was evaluated by a mating assay. In the mating analysis of monospores with mutations in Fvpal1, it was found that this mutation plays an important role in determining the color of the fruiting body. Furthermore, the deletion (Δ112RT113) in Fvpal1 is located between motifs that play a key role in the catalytic function of FvPAL1. These results suggest that this mutation can be used as an effective marker for the color-specific breeding of F. velutipes, a representative edible mushroom.

2.
Ann Lab Med ; 41(2): 214-220, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33063683

RESUMO

The correct identification of filamentous fungi is challenging. We evaluated the performance of the VITEK MS v3.0 system (bioMérieux, Marcy-l'Étoile, France) for the identification of a wide spectrum of clinically relevant filamentous fungi using a Korean collection. Strains that were added to the upgraded v3.2 database were additionally identified by the VITEK MS v3.2 system. Of the 105 tested isolates, including 37 Aspergillus (nine species), 41 dermatophytes (seven species), and 27 other molds (17 species), 43 (41.0%) showed "no identification" or "multiple species identification" results at the initial VITEK MS testing; these isolates were retested using the same method. Compared with sequence-based identification, the correct identification rate using VITEK MS for Aspergillus, dermatophytes, other molds, and total mold isolates was 67.6%, 56.1%, 48.1%, and 58.1% at the initial testing and 94.6%, 78.0%, 55.6%, and 78.1% with retesting, respectively. Following retesting, 19 (18.1%) and two (1.9%) isolates showed "no identification" and "misidentification" results, respectively. VITEK MS reliably identified various filamentous fungi recovered in Korea, with a very low rate of misidentification.


Assuntos
Fungos , Humanos , República da Coreia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
3.
Korean J Parasitol ; 57(3): 313-318, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31284357

RESUMO

In recent years, the taeniasis has been rarely reported in the Republic of Korea (Korea). But in this study, we intend to report 4 taeniasis cases caused by Taenia saginata during a 5-month period (February to June 2018) at a unversity hospital in Gwangju, Korea. Worm samples (proglottids) discharged from all cases were identified by phenotypic and molecular diagnostics. Mitochondrial cytochrome c oxidase subunit I sequences showed 99.4-99.9% identity with T. saginata but, differed by 4% from T. asiatica and by 7% from T. multiceps, respectively. We found that tapeworms in 2 cases (Cases 2 and 3) yielded exactly the same sequences between them, which differed from those in Cases 1 and 4, suggesting intra-species variation in tapeworms. These taeniasis cases by T. saginata infection in this study, which occurred within a limited time period and region, suggest the possibility of a mini-outbreak. This study highlights the need for further epidemiological investigation of potentially overlooked cases of T. saginata infection in Korea.


Assuntos
Taenia saginata/isolamento & purificação , Teníase/parasitologia , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Proteínas de Helminto/genética , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , República da Coreia , Taenia saginata/classificação , Taenia saginata/genética , Teníase/diagnóstico
5.
BMC Infect Dis ; 19(1): 115, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30727977

RESUMO

BACKGROUND: Clonorchiasis is the common parasitic infection in the general population of the Republic of Korea, however, taeniasis is scarcely reported recently. Here, we describe a case of co-infection with the cestode T. saginata in a patient with subclinical clonorchiasis diagnosed by a combination of diagnostic tools in Korea. CASE PRESENTATION: A 56-year-old man visited the hospital having passed proglottids in his stool for the past two months and brought a stool sample with segments to our hospital. He had no abdominal symptoms, such as nausea, vomiting, abdominal pain, diarrhea, or constipation. He used to consume raw beef and fish frequently. We could not find evidence of gravid proglottids which contain fully developed uteri filled with ova or branched uterine structures, within the submitted sample. To identify the tapeworm species, we carried out molecular analyses on the proglottids. The cox1 and ef1a sequences had a 100% match with those of T. saginata and differed from the sequences of the other Taenia species. Upon examination of stool samples fixed by formalin-ether concentration method, no Taenia species ova were observed in 10 slides. Instead, C. sinensis ova were observed, despite the level of IgG specific to C. sinensis being within the normal range. The patient was treated with praziquantel (25 mg/kg, three times a day) for 3 days, and subsequently C. sinensis ova were not found in his stool. CONCLUSION: Our case indicates that a combination of morphological, serological, and molecular diagnostic tools should be used for the accurate diagnosis of subclinical parasitic infections.


Assuntos
Clonorquíase/diagnóstico , Taenia saginata/genética , Teníase/diagnóstico , Animais , Bovinos , Clonorquíase/tratamento farmacológico , Clonorquíase/etiologia , Coinfecção/complicações , Coinfecção/parasitologia , Ciclo-Oxigenase 1/genética , Fezes/parasitologia , Proteínas de Helminto/genética , Humanos , Masculino , Pessoa de Meia-Idade , Fator Tu de Elongação de Peptídeos/genética , Praziquantel/uso terapêutico , República da Coreia , Taenia saginata/patogenicidade , Teníase/tratamento farmacológico , Teníase/etiologia
6.
Am J Respir Crit Care Med ; 199(6): 784-794, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30252496

RESUMO

RATIONALE: Use of Xpert MTB/RIF assay as a substitute for smear microscopy in routine clinical practice remains unexplored in an intermediate-tuberculosis-burden setting. OBJECTIVES: To compare the diagnostic performance of Xpert and smear microscopy, based on sampling time and location, correlation of Xpert semiquantitative category with smear grade and time to culture positivity, and compliance of reporting time with defined standard time. METHODS: Consecutive sputum samples collected from 2,952 suspected pulmonary tuberculosis patients over a 3-year period were tested by Xpert, smear microscopy, and liquid culture as part of routine diagnostics in South Korea. MEASUREMENTS AND MAIN RESULTS: Based on the analysis of a single sputum specimen per patient, of 2,952 samples, 263 (8.9%) were culture-confirmed tuberculosis and 265 (9.0%) were nontuberculous mycobacteria. The overall sensitivity and specificity were 74.1% and 97.5% for Xpert versus 38.8% and 96.7% for smear microscopy, respectively (P < 0.0001; P > 0.05). Of 82 smear-positive nontuberculous mycobacteria, 81 (98.8%) were accurately excluded by Xpert. Sampling time and location significantly affected the performance of smear microscopy but not that of Xpert. Xpert semiquantitative category strongly correlated with smear grade (γGoodman-Kruskal = 0.982; P < 0.0001) and time to culture positivity (γGoodman-Kruskal = -0.962; P < 0.0001). Median reporting time and its compliance rate within 24 hours were 3.1 hours and 96.3% for Xpert versus 19.1 hours and 88.7% for smear microscopy, respectively (P < 0.0001; P < 0.05). CONCLUSIONS: Xpert provides faster, more stable, and superior results compared with smear microscopy, in addition to its strong correlation with smear grade. Xpert might replace smear microscopy as the first-line diagnostic test for pulmonary tuberculosis in routine clinical practice in an intermediate-burden setting.


Assuntos
Microscopia/métodos , Técnicas de Diagnóstico Molecular , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Humanos , República da Coreia , Sensibilidade e Especificidade
7.
Nanotechnology ; 26(5): 055305, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25590555

RESUMO

Ag-nanomesh-based highly bendable conducting electrodes are developed using a combination of metal nanotransfer printing and embossing for the 6-inch wafer scale. Two Ag nanomeshes, including pitch sizes of 7.5 and 10 µm, are used to obtain highly transparent (approximately 85% transmittance at a wavelength of 550 nm) and electrically conducting properties (below 10 Ω sq(-1)). The Ag nanomeshes are also distinguished according to the fabrication process, which is called transferred or embedded Ag nanomesh on polyethylene terephthalate (PET) substrate, in order to compare their stability against bending stress. Then the enhancement of bending stability when the Ag nanomesh is embedded in the PET substrate is confirmed.

8.
Opt Lett ; 39(20): 5901-4, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25361115

RESUMO

We report an organic light emitting diode (OLED) with a hydrogen silsesquioxane as a scattering material, for enhancing light extraction efficiency. A tetragonal photonic crystal was used as pattern type, and fabricated using a direct printing technique. Planarization was accomplished using TiO2 solgel solution, having a refractive index identical to that of the indium zinc oxide transparent electrode. The current efficiency and power efficiency of the OLED increased by 17.3% and 43.4% at 10 mA/cm², respectively, without electric degradation.

9.
Nanotechnology ; 25(22): 225301, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24833169

RESUMO

Silica nanostructures were fabricated on glass substrate using a microwave assisted direct patterning (MADP) process, which is a variety of soft lithography. During the MADP process using polydimethylsiloxane (PDMS), mold and microwave heating are performed simultaneously. Blanket thin film and micro- to nano-sized structures, including moth-eye patterns of SiO2, which consisted of coalesced silica nanoparticles, were formed on glass substrates from SiO2 nano-particle dispersed solutions with varied microwave heating time. Optical properties and surface morphologies of micro-sized hemisphere, nano-sized pillar, moth-eye and 50 nm sized line/space silica patterns were measured using UV-vis and a scanning electron microscope. X-ray diffraction analysis of SiO2 thin films with and without microwave heating was also carried out.

10.
ACS Nano ; 8(2): 1907-12, 2014 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-24446833

RESUMO

We present an amorphous Si anode deposited on a Cu nanopillar current collector, fabricated using a thermal roll-to-roll process followed by electroformation and LPCVD, for application in high-rate Li-ion batteries. Cu nanopillar current collectors with diameters of 250 and 500 nm were patterned periodically with 1 µm pitch and 2 µm height to optimize the diameters of the pillars for better electrochemical performance. Void spaces between Cu nanopillars allowed not only greater effective control of the strain caused by the Si expansion during lithiation than that allowed by a nonpatterned electrode but also significantly improved cycle performance even at 20 C measured after the same rate test: After 100 cycles at 0.5 C, the patterned electrodes with 250 and 500 nm diameter nanopillars showed high capacity retentions of 86% and 84%, respectively. These electrodes retained discharge capacities of 1057 and 780 mAh/g even at 20 C, respectively.

11.
J Nanosci Nanotechnol ; 12(4): 3364-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22849125

RESUMO

Carbon based spin-on organic hardmask (C-SOH) was used as an imprint resin to fabricate sub 50 nm sized patterns. Imprinting of C-SOH was done with a polyurethaneacrylate (PUA) stamp. Patternability and etch resistance of the C-SOH resin was compared to poly(methyl methacrylate) (PMMA). C-SOH can be patterned at the nanosize using imprint lithography and exhibits superior etch resistance, especially for F-based plasmas. Due to the poor etch resistance of imprint resin such as PMMA, it is seldom used as an etch mask to form nano-structures by etching the Si3N4 layer. However, such a nano-structure was able to be formed by etching the Si3N4 layer using C-SOH as an etch mask.

12.
Nanoscale Res Lett ; 6(1): 458, 2011 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-21767390

RESUMO

UV curing nanoimprint lithography is one of the most promising techniques for the fabrication of micro- to nano-sized patterns on various substrates with high throughput and a low production cost. The UV nanoimprint process requires a transparent template with micro- to nano-sized surface protrusions, having a low surface energy and good flexibility. Therefore, the development of low-cost, transparent, and flexible templates is essential. In this study, a flexible polyethylene terephthalate (PET) film coated with a fluorinated polymer material was used as an imprinting mold. Micro- and nano-sized surface protrusion patterns were formed on the fluorinated polymer layer by the hot embossing process from a Si master template. Then, the replicated pattern of the fluorinated polymer, coated on the flexible PET film, was used as a template for the UV nanoimprint process without any anti-stiction coating process. In this way, the micro- to nano-sized patterns of the original master Si template were replicated on various substrates, including a flat Si substrate and curved acryl substrate, with high fidelity using UV nanoimprint lithography.

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