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1.
Arch Microbiol ; 206(4): 168, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38489085

RESUMEN

One Gram stain-positive, catalase-negative, α-hemolytic, chain-forming or paired cocci, designated ST22-14T, was isolated from a blood culture of a child with suspected infection. The results of 16S rRNA gene sequences analyses showed that the most closely related species to strain ST22-14T were "Streptococcus vulneris" DM3B3T (99.2%), Streptococcus mitis NCTC 12261T (99.0%), "Streptococcus gwangjuense" ChDC B345T, (99.0%), Streptococcus oralis subsp. dentisani 7747T (99.0%), Streptococcus downii CECT 9732T (99.0%), and Streptococcus infantis ATCC 700779T (98.9%). The genome of strain ST22-14T consists of 2,053,261 bp with a G + C content of 39.4%. Average nucleotide identity values between strain ST22-14T and Streptococcus mitis NCTC 12261T or other five species were from 82.2 to 88.0%. In silico DNA-DNA hybridization of ST22-14T showed an estimated DNA reassociation value of 34.6% with the closest species. The main cellular fatty acids of strain ST22-14T were 16:0, 18:0, 14:0, 18:1ω7c and 18:1ω6c. Based on these results, strain ST22-14T should be classified as a novel species of genus Streptococcus, for which the name Streptococcus taonis sp. nov. is proposed (type strain ST22-14T = NBRC 116002T = BCRC 81402T).


Asunto(s)
Cultivo de Sangre , Streptococcus , Niño , Humanos , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptococcus/genética , ADN Bacteriano/genética , Filogenia , Ácidos Grasos , Técnicas de Tipificación Bacteriana , Hibridación de Ácido Nucleico
2.
Small ; 19(19): e2207038, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36755212

RESUMEN

Crystal-phase-engineering provides a powerful strategy for regulating the catalytic performance yet remains great challenge. Herein, the kinetic-modulated crystal-phase-control of Ru nanosheet assemblies (Ru NAs) is demonstrated by simply altering the concentration of citric acid (CA). Detailed experimental results reveal that high concentration of CA retards the growth kinetics and thus leads to the formation of metastable face-centered cubic (fcc) Ru NAs, while low concentration of CA results in the fast growth kinetics and the preferential formation of Ru NAs with stable hexagonal close packed (hcp) phase. Moreover, Ru NAs with different phases are used as catalyst for hydrogen oxidation reaction (HOR) to evaluate the effects of crystal phase on catalytic performance. Impressively, Ru NAs with fcc phase display a mass activity of 2.75 A mgRu -1 at 50 mV, which is much higher than those of Ru NAs with fcc/hcp (1.02 A mgRu -1 ) and hcp (0.74 A mgRu -1 ) phases. Theoretical calculations show that fcc Ru NAs display weaker adsorption toward * H and lower energy barrier toward the rate-determining step (RDS) during HOR. This work provides a facile strategy for regulating the crystal phase of Ru nanocrystals, which may attract rapid interests of researchers in materials, chemistry, and catalysis.

3.
Angew Chem Int Ed Engl ; 62(20): e202218924, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-36932034

RESUMEN

Electrochemical two-electron oxygen reduction reaction (2 e- ORR) to produce hydrogen peroxide (H2 O2 ) is a promising alternative to the energetically intensive anthraquinone process. However, there remain challenges in designing 2 e- ORR catalysts that meet the application criteria. Here, we successfully adopt a microwave-assisted mechanochemical-thermal approach to synthesize hexagonal phase SnO2 (h-SnO2 ) nanoribbons with largely exposed edge structures. In 0.1 M Na2 SO4 electrolyte, the h-SnO2 catalysts achieve the excellent H2 O2 selectivity of 99.99 %. Moreover, when employed as the catalyst in flow cell devices, they exhibit a high yield of 3885.26 mmol g-1 h-1 . The enhanced catalytic performance is attributed to the special crystal structure and morphology, resulting in abundantly exposed edge active sites to convert O2 to H2 O2 , which is confirmed by density functional theory calculations.

4.
J Am Chem Soc ; 144(1): 416-423, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34878269

RESUMEN

Electronic structure modulation among multiple metal sites is key to the design of efficient catalysts. Most studies have focused on regulating 3d transition-metal active ions through other d-block metals, while few have utilized f-block metals. Herein, we report a new class of catalyst, namely, UCoO4 with alternative CoO6 and 5f-related UO6 octahedra, as a unique example of a 5f-covalent compound that exhibits enhanced electrocatalytic oxygen evolution reaction (OER) activity because of the presence of the U 5f-O 2p-Co 3d network. UCoO4 exhibits a low overpotential of 250 mV at 10 mA cm-2, surpassing other unitary cobalt-based catalysts ever reported. X-ray absorption spectroscopy revealed that the Co2+ ion in pristine UCoO4 was converted to high-valence Co3+/4+, while U6+ remained unchanged during the OER, indicating that only Co was the active site. Density functional theory calculations demonstrated that the OER activity of Co3+/4+ was synergistically enhanced by the covalent bonding of U6+-5f in the U 5f-O 2p-Co 3d network. This study opens new avenues for the realization of electronic structure manipulation via unique 5f involvement.

5.
Chemistry ; 28(66): e202201881, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36031561

RESUMEN

Currently, the excessive consumption of fossil fuels is accompanied by massive emissions of CO2 , leading to severe energy shortages and intensified global warming. It is of great significance to develop and use renewable clean energy while reducing the concentration of CO2 in the atmosphere. Photocatalytic technology is a promising strategy for carbon dioxide conversion. Clearly, the achievement of the above goals largely depends on the design and construction of catalysts. This review is mainly focused on the application of 2D materials for photocatalytic CO2 reduction. The contribution of synthetic strategies to their structure and performance is emphasized. Finally, the current challenges, and prospects of 2D materials for photoreduction of CO2 with high efficiency, even for practical applications are discussed. It is hoped that this review can provide some guidance for the rational design, controllable synthesis of 2D materials, and their application for efficient photocatalytic CO2 reduction.

6.
Arch Microbiol ; 204(7): 359, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35657449

RESUMEN

A new α-haemolytic streptococcal strain, designated DM3B3T, was isolated from the wound of a diabetic foot ulcer (DFU) patient. Phylogenetic analysis based on 16S rRNA full-gene sequencing (1563 bp) revealed highest sequence similarity to Streptococcus mitis (99.7%), followed by "Streptococcus gwangjuense" (99.6%), and Streptococcus pseudopneumoniae (99.5%). Comparison of five housekeeping genes, groEL, rpoB, sodA, recA and pheS, revealed that strain DM3B3T was well separated from the Streptococcus reference strains. The complete genome of strain DM3B3T consisted of 1,963,039 bp with a G + C content of 41.0 mol%. Average nucleotide identity values between strain DM3B3T and Streptococcus mitis NCTC 12261T, "Streptococcus gwangjuense" ChDC B345T, and Streptococcus pseudopneumoniae ATCC BAA-960T were 93.8%, 94.4%, and 92.2%, respectively. The highest digital DNA-DNA hybridization value with respect to the closest species was 57.5%, i.e., below the species cut-off of 70% hybridization. The main cellular fatty acids of strain DM3B3T were 16:0, 18:1ω7c, 18:1ω9c and 18:0. On the basis of phylogenetic, genotypic and phenotypic data, we propose to classify this isolate as representative of a novel species of the genus Streptococcus, Streptococcus vulneris sp. nov., in reference to its isolation from wound, with strain DM3B3T (= NBRC 114638T = BCRC 81288T) as the type strain.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos , Humanos , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptococcus/genética
7.
Artículo en Inglés | MEDLINE | ID: mdl-35180047

RESUMEN

A coccus-shaped organism, designated ALS3T, was isolated from fresh coffee cherries collected at a farm located in the Ali Mountain region of Taiwan. Sequence analysis of its 16S rRNA gene indicated that strain ALS3T belongs to the genus Enterococcus and has more than 98.5 % sequence similarity to Enterococcus pallens and Enterococcus hermanniensis. When comparing the ALS3T genome with these two type strains, the average nucleotide identity values and digital DNA-DNA hybridization values were 72.6-73.3 and 19.2 %, respectively. The G+C content of the genomic DNA from strain ALS3T was 35.6 mol%. Results of sequence analysis, together with enzymatic activities and characteristics of carbohydrate metabolism, indicated that strain ALS3T is distinct and represents a novel species, for which the name Enterococcus alishanensis sp. nov. is proposed. The type strain is ALS3T (=NBRC 109593T=BCRC 80605T).


Asunto(s)
Coffea/microbiología , Enterococcus/clasificación , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Enterococcus/aislamiento & purificación , Ácidos Grasos/química , Genes Bacterianos , Ácido Láctico , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Semillas/microbiología , Análisis de Secuencia de ADN , Taiwán
8.
Int J Syst Evol Microbiol ; 72(11)2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36748588

RESUMEN

A Gram-positive, facultatively anaerobic, catalase-negative, fructose-dependent strain (W13T) was isolated from the gut of honeybee (Apis mellifera). Phylogenetic analysis based on 16S rRNA gene sequencing indicated that strain W13T represents a distinct line of descent within the genus Fructobacillus, with the closest neighbours being Fructobacillus broussonetiae BCRC 81240T (98.9 % sequence similarity) and Fructobacillus durionis DSM 19113T (96.8 % sequence similarity). Comparative sequencing of the additional phylogenetic markers rpoC and recA confirmed the 16S rRNA gene tree topology. The complete genome of strain W13T consisted of 1 292 712 bp with a G+C content of 48.3 mol%. Pairwise comparisons of the average nucleotide identity values and digital DNA-DNA hybridization values between the genomes of W13T and its close phylogenetic neighbours, F. broussonetiae BCRC 81240T and F. durionis DSM 19113T, resulted in 76.2-84.1 % and 20.2-27.6 %, respectively. The main cellular fatty acids of strain W13T were C16 : 0, C18 : 1 ω9c and C18 : 1 ω7c. Thus, we propose a novel species within the genus Fructobacillus, with the name Fructobacillus apis sp. nov. and the type strain is W13T (= NBRC 115637T=BCRC 81365T).


Asunto(s)
Ácidos Grasos , Abejas , Animales , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Composición de Base , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Hibridación de Ácido Nucleico
9.
Macromol Rapid Commun ; 43(23): e2200538, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36056702

RESUMEN

Carbon fiber reinforced polymer (CFRP) composites are indispensable in a variety of applications, because of their high specific strength. CFRPs are generally constructed by carbon fibers as reinforcements and crosslinked polymers as binders. Due to the irreversible nature of the crosslinked polymers, CFRPs are neither repairable nor recyclable. Once the material is damaged or out of service, landfill or incineration is the typical way to deal with the waste. These methods take no advantages of the residue value of the waste and add burdens to the environment. To reduce waste and cost, it is desirable to develop effective recycling technologies to reserve the residue value of carbon fiber and polymer matrix. In the past decade, chemical recycling by cleaving the covalent bonds in a solvent has been considered as an ideal path for the recycling of CFRP wastes, because it has the potential to recover both valuable CFs and polymer matrix. In this review, the discussion is focused on the progress in the chemical recycling of CFRP. The primary matrix resin of CFRP discussed in this review is epoxy resin which is the most widely used polymer matrix. In addition, the challenges and outlook are provided.

10.
Proc Natl Acad Sci U S A ; 116(9): 3524-3529, 2019 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-30733287

RESUMEN

RAP1-interacting adapter molecule (RIAM) mediates RAP1-induced integrin activation. The RAS-association (RA) segment of the RA-PH module of RIAM interacts with GTP-bound RAP1 and phosphoinositol 4,5 bisphosphate but this interaction is inhibited by the N-terminal segment of RIAM. Here we report the structural basis for the autoinhibition of RIAM by an intramolecular interaction between the IN region (aa 27-93) and the RA-PH module. We solved the crystal structure of IN-RA-PH to a resolution of 2.4-Å. The structure reveals that the IN segment associates with the RA segment and thereby suppresses RIAM:RAP1 association. This autoinhibitory configuration of RIAM can be released by phosphorylation at Tyr45 in the IN segment. Specific inhibitors of focal adhesion kinase (FAK) blocked phosphorylation of Tyr45, inhibited stimulated translocation of RIAM to the plasma membrane, and inhibited integrin-mediated cell adhesion in a Tyr45-dependent fashion. Our results reveal an unusual regulatory mechanism in small GTPase signaling by which the effector molecule is autoinhibited for GTPase interaction, and a modality of integrin activation at the level of RIAM through a FAK-mediated feedforward mechanism that involves reversal of autoinhibition by a tyrosine kinase associated with integrin signaling.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/química , Integrinas/química , Proteínas de la Membrana/química , Conformación Proteica , Proteínas de Unión a Telómeros/química , Proteínas Adaptadoras Transductoras de Señales/genética , Adhesión Celular/genética , Membrana Celular/química , Cristalografía por Rayos X , Proteína-Tirosina Quinasas de Adhesión Focal/química , Proteína-Tirosina Quinasas de Adhesión Focal/genética , GTP Fosfohidrolasas/química , GTP Fosfohidrolasas/genética , Humanos , Proteínas de la Membrana/genética , Fosforilación , Complejo Shelterina , Transducción de Señal , Proteínas de Unión a Telómeros/genética
11.
Arch Microbiol ; 203(9): 5475-5482, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34417650

RESUMEN

Sequences targeted at the V3 and V4 16S rRNA hypervariable regions of a streptococcal strain (P1L01T) isolated from vaginal swabs of a pregnant woman with diabetes were 100% similar to those of Streptococcus anginosus subsp. whileyi. However, phylogenetic analysis based on 16S rRNA full-gene sequencing (1562 bp) revealed highest sequence similarity to Streptococcus periodonticum (98.7%), followed by Streptococcus anginosus subsp. whileyi (98.7%), and Streptococcus anginosus subsp. anginosus (98.4%). Phylogenies of housekeeping genes rpoB and groEL were compared to improve classification, and the results showed a clear separation between strain P1L01T and closely related Streptococcus type strains. The complete genome of strain P1L01T consisted of 2,108,769 bp with a G + C content of 38.5 mol%. Average nucleotide identity values, based on genome sequencing, between strain P1L01T and Streptococcus periodonticum KCOM 2412T, Streptococcus anginosus subsp. whileyi CCUG 39159T, and Streptococcus anginosus subsp. anginosus NCTC 10713T were 95.5%, 94.3%, and 95.3%, respectively. The highest in silico DNA-DNA hybridization value with respect to the closest species was 66.2%, i.e., below the species cutoff of 70% hybridization. The main cellular fatty acids of strain P1L01T were 16:0, 18:1ω7c, and 14:0. On the basis of phylogenetic, genotypic and phenotypic data, we propose to classify this isolate as representative of a novel species of the genus Streptococcus, Streptococcus vaginalis sp. nov., in reference to its isolation from vaginal swabs, with strain P1L01T (= NBRC 114754T = BCRC 81289T) as the type strain.


Asunto(s)
Diabetes Mellitus , Mujeres Embarazadas , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos , Femenino , Humanos , Hibridación de Ácido Nucleico , Filogenia , Embarazo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptococcus/genética
12.
J Chem Phys ; 154(16): 164707, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33940797

RESUMEN

This work demonstrates the first example of interfacial manipulation in a hybrid photocatalyst based on poly(3-hexylthiophene-2,5-diyl) (P3HT) nanoparticle and graphene oxide (GO) bulk heterojunctions to efficiently reduce CO2 into selective industrial hydrocarbons under gas-phase reaction and visible-light illumination. High selectivity of chemical products (methanol and acetaldehyde) was observed. Moreover, the hybrid photocatalyst's solar-to-fuel conversion efficiency was 13.5 times higher than that of pure GO. The increased production yield stems from the co-catalytic and sensitizing role of P3HT in the hybrid system due to its ability to extend light absorption to the visible range and improve interfacial charge transfer to GO. The hybrid P3HT-GO formed a type II heterojunction, and its static and dynamic exciton behaviors were examined using fluorescence spectroscopy and exciton lifetime mapping. A reduced fluorescence decay time was observed by interfacial manipulation for improved dispersion, indicating a more efficient charge transfer from the excited P3HT to GO. Thus, the conducting polymer nanoparticles, 2D nanocarbon, have demonstrated superior performance as a metal-free, non-toxic, low-cost, and scalable heterogeneous photocatalyst for CO2 reduction to solar fuel, a solid-gas system.

13.
Nano Lett ; 20(7): 5008-5016, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32515975

RESUMEN

Monitoring and characterization methods that provide performance tracking of hydrogen evolution reaction (HER) at the single-nanoparticle level can greatly advance our understanding of catalysts' structure and activity relationships. Electrochemiluminescence (ECL) microscopy is implemented for the first time to identify HER activities of single nanocatalysts and to provide a direction for further optimization. Here, we develop a novel ECL blinking technique at the single-nanoparticle level to directly monitor H2 nanobubbles generated from hollow carbon nitride nanospheres (HCNSs). The ECL ON and OFF mechanisms are identified being closely related to the generation, growth, and collapse of H2 nanobubbles. The power-law distributed durations of ON and OFF states demonstrate multiple catalytic sites with stochastic activities on a single HCNS. The power-law coefficients of ECL blinking increase with improved HER activities from modified HCNSs with other active HER catalysts. Besides, ECL blinking phenomenon provides an explanation for the low cathodic ECL efficiency of semiconductor nanomaterials.

14.
Angew Chem Int Ed Engl ; 60(11): 5948-5958, 2021 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-33289255

RESUMEN

The development of versatile nanotheranostic platforms that integrate both diagnostic and therapeutic functions have always been an intractable challenge in precise cancer treatment. Herein, an aptamer-tethered deoxyribonucleic acids-gold particle (Apt-DNA-Au) nanomachine has been developed for in situ imaging and targeted multimodal synergistic therapy of mammary carcinoma. Upon specifically internalized into MCF-7 cells, the tumor-related TK1 mRNA activates the Apt-DNA-Au nanomachine by DNA strand displacement cascades, resulting in the release of the fluorophore and antisense DNA as well as the aggregation of AuNPs for in situ imaging, suppression of survivin expression and photothermal therapy, respectively. Meanwhile, the controlled released drugs are used for chemotherapy, while under the laser irradiation the loaded photosensitizer produces reactive oxygen species (ROS) for photodynamic therapy. The results confirm that the proposed Apt-DNA-Au nanomachine provides a powerful nanotheranostic platform for in situ imaging-guided combinatorial anticancer therapy.


Asunto(s)
Antineoplásicos/farmacología , ADN/farmacología , Doxorrubicina/farmacología , Oro/farmacología , Imagen Óptica , ARN Mensajero/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , ADN/química , Doxorrubicina/síntesis química , Doxorrubicina/química , Femenino , Oro/química , Humanos , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/patología , Nanopartículas del Metal/química , Tamaño de la Partícula , Terapia Fototérmica , Espectrometría de Fluorescencia , Nanomedicina Teranóstica
15.
Int J Syst Evol Microbiol ; 70(3): 1585-1590, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32228772

RESUMEN

A novel lactic acid bacterium, strain MB7T, was isolated from lychee in Taiwan. MB7T is Gram-staining-positive, catalase-negative, non-motile, non-haemolytic, facultatively anaerobic, coccoid-shaped, heterofermentative and mainly produces d-lactic acid from glucose. Comparative analysis of 16S rRNA, pheS and rpoA gene sequences has demonstrated that the novel strain represented a member of the genus Leuconostoc. 16S rRNA gene sequencing results indicated that MB7T had the same sequence similarity of 99.25 % to four type strains of members of the genus Leuconostoc: Leuconostoc mesenteroides subsp. dextranicum DSM 20484T, Leuconostoc mesenteroides subsp. jonggajibkimchii DRC 1506T, Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293T and Leuconostoc suionicum DSM 20241T. Additionally, high 16S rRNA sequence similarities were also observed with Leuconostoc mesenteroides subsp. cremoris ATCC 19254T (99.12 %) and Leuconostoc pseudomesenteroides NRIC 1777T (98.69 %). When comparing the genomes of these type strains, the average nucleotide identity values and digital DNA-DNA hybridization values of MB7T with these type strains were 76.57-80.53 and 22.0-22.6 %, respectively. MB7T also showed different phenotypic characteristics to other most closely related species of the genus Leuconostoc, such as carbohydrate metabolizing ability, halotolerance and growth at various pHs. On the basis of phenotypic and genotypic properties, strain MB7T represents a novel species belonging to the genus Leuconostoc, for which the name Leuconostoc litchii sp. nov. is proposed. The type strain is MB7T (=BCRC 81077T=NBRC 113542T).


Asunto(s)
Frutas/microbiología , Leuconostoc/clasificación , Litchi/microbiología , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Fermentación , Ácido Láctico , Leuconostoc/aislamiento & purificación , Leuconostoc mesenteroides , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Taiwán
16.
Appl Opt ; 59(8): 2632-2640, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32225808

RESUMEN

The majority of optical lenses have spherical surface profiles because they are convenient to fabricate. Replacing spherical optics with aspheric optics leads to smaller size, lighter weight, and less complicated optical systems with a superior imaging quality. However, fabrication of aspheric lenses is expensive and time-consuming. Here, we introduce a straightforward and low-cost casting method to fabricate polymeric aspheric lenses. An elastomeric ferrogel was formed into an aspherical profile by using a designed magnetic field and then was used as a mold. Different types of aspherical profiles from parabola to hyperbola can be formed with this method by tuning the magnetic field. A home-built Shack-Hartmann sensor was employed to characterize the cast polymeric lenses. The effects of magnetic field intensity, gradient of the magnetic field, and magnetic susceptibility of the ferrogel on the lens profiles were investigated. This technique can be used for rapid-forming polymeric aspherical lenses with different sizes and shapes.

17.
Sens Actuators B Chem ; 292: 263-269, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31303694

RESUMEN

Sulfane sulfur species are newly recognized signaling molecules that play physiological roles in many biological events. The development of new technologies for the detection of sulfane sulfurs is important. Point-of-care (POC) devices are in-field rapid and low-cost detectors that are more convenient to use than bulky and expensive standard instruments. In this report, a new fluorescent probe (SSP5) was designed to detect sulfane sulfurs using a POC sulfane sulfur smartphone spectrum apparatus (S4A). This probe proved to be sensitive and selective for sulfane sulfur species over other biologically relevant sulfur species such as cysteine and H2S. The low-cost and compact S4A has achieved comparable performance to standard laboratory equipment in both a standard buffer system and a synthetic urine system. The proposed system (SSP5 + S4A) has the potential for high accuracy and rapid detection of sulfane sulfur species in remote and low resource settings.

18.
Arch Virol ; 163(11): 3113-3117, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30051342

RESUMEN

Porcine deltacoronavirus (PDCoV) was initially documented in Hong Kong and later in the United States, South Korea, and Thailand. To investigate if PDCoV is also present in Taiwan, three swine coronaviruses-PDCoV, porcine epidemic diarrhea virus (PEDV), and transmissible gastroenteritis coronavirus (TGEV)-were tested using real-time reverse transcription polymerase chain reaction (rRT-PCR) in 172 rectal swab samples from piglets exhibiting diarrhea between January 2016 and May 2017 on 68 pig farms in Taiwan. The rRT-PCR results were positive for PDCoV (29/172, 16.9%), PEDV (36/172, 20.9%), TGEV (2/172, 1.2%), and coinfections (16/172, 9.3%). After cloning and sequencing, PDCoV nucleocapsid genes were analyzed. Phylogeny results indicated that the nucleotide sequences of all isolates were like those reported in other countries. To further trace PDCoV in the period of 2011 to 2015, an enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies against PDCoV. The results showed that 279 of 1,039 (26.9%) sera were positive for the PDCoV nucleocapsid protein, implying that PDCoV might have existed in Taiwan before 2011.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Coronavirus/veterinaria , Coronavirus/genética , Coronavirus/aislamiento & purificación , Diarrea/veterinaria , Enfermedades de los Porcinos/virología , Animales , Coronavirus/clasificación , Coronavirus/inmunología , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/virología , Diarrea/sangre , Diarrea/virología , Ensayo de Inmunoadsorción Enzimática , Femenino , Masculino , Filogenia , Análisis de Secuencia de ADN , Porcinos , Enfermedades de los Porcinos/sangre , Taiwán
19.
Sens Actuators B Chem ; 275: 300-305, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37576435

RESUMEN

In this work, we present an ultra-low-cost smartphone device for in situ quantification of OP poisoning severity. The performance of the lens-less smartphone spectrum apparatus (LeSSA) is evaluated using standard human Interleukin-6 (IL-6) immunoassay kits. Upon dose-response curve fitting, LeSSA demonstrates an accuracy of 99.5%. The limit of detection (LOD) of LeSSA was evaluated through comparison of 6.4 pg/ml with standard laboratory grade UV-vis spectrophotometer at 5.5 pg/ml. Evaluating the capacity of LeSSA in spike solution by combining plasma cholinesterase (PChE) and human plasma shows consistency at agreement of 97.6% between LeSSA and the laboratory instrument. For application demonstration, the activity of PChE for 24 agricultural workers' plasma samples was measured with LeSSA, showing exceptional agreement (r2 = 0.92) with the laboratory instrument reference. In addition to near laboratory grade accuracy, the total manufacturing cost of LeSSA is only $20 USD highlighting it's affordability. With LeSSA, clinicians can evaluate OP poisoning severity without the need to transport patient samples to facilities at far distances. Utilizing LeSSA, immediate results can be used for administration of appropriate treatment.

20.
Int J Syst Evol Microbiol ; 67(12): 5144-5149, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29058648

RESUMEN

Two Gram-stain-positive, catalase-negative, rod-shaped, bacterial strains (313T and 311) were isolated from banana fruits in Taiwan. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the highest similarity to both strains corresponded to the type strain of Lactobacillus nantensis (99.19 %), followed by Lactobacillus crustorum (98.99 %), Lactobacillus heilongjiangensis (98.59 %) and Lactobacillus farciminis (98.52 %). Phylogenetic analysis based on the sequences of two housekeeping genes, pheS and rpoA, revealed that these two strains were well separated from the Lactobacillus reference strains. DNA-DNA relatedness values revealed genotype separation of the two strains from the above four species. The DNA G+C content of strain 313T was 35.5 mol%. The strains were homofermentative and mainly produced l-lactic acid from glucose. The major cellular fatty acids of strain 313T were 18 : 1ω6c and/or 18 : 1ω7c, 16 : 0, and 19 : 1ω6c and/or 19 : 0 cyclo ω10c. Based on their physiological and genotypic characteristics, the isolates represent a novel species of the genus Lactobacillus, for which the name Lactobacillusmusae sp. nov. is proposed. The type strain is 313T=NBRC 112868T=BCRC 81020T).


Asunto(s)
Frutas/microbiología , Lactobacillus/clasificación , Musa/microbiología , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Fermentación , Ácido Láctico , Lactobacillus/genética , Lactobacillus/aislamiento & purificación , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Taiwán
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