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1.
Phys Chem Chem Phys ; 26(26): 18041-18047, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38895773

RESUMO

Nanostructured thermoelectric materials ideally reduce lattice thermal conductivity without harming the electrical properties. Thus, to truly improve the thermoelectric performance, the quality factor, which is proportional to the weighted mobility divided by the lattice thermal conductivity of the material, must be improved. Precipitates of In2Te3 form in the state-of-the-art Bi2Te3 with crystallographic alignment to the Bi2Te3 structure. Like epitaxy in films, this can be called endotaxy in solids. This natural epitaxy in a 3-dimensional solid is ideally situated to scatter phonons but produces minimal electronic scattering and, therefore, maintains high mobility. Here, we study the effects of In-alloying in Bi2Te3 at high In concentrations (about 4 at%), enough to produce the endotaxial microstructure. It is found that such concentrations of indium in Bi2Te3 significantly alter the electronic structure, reducing the effective mass and weighted mobility so significantly as to effectively destroy the thermoelectric properties even though the lattice thermal conductivity is successfully reduced.

2.
EMBO Rep ; 22(1): e50663, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33225575

RESUMO

Castration of young males is widely used in the cattle industry to improve meat quality, but the mechanism linking hypogonadism and host metabolism is not clear. Here, we use metataxonomic and metabolomic approaches to evaluate the intestinal microbiota and host metabolism in male, castrated male (CtM), and female cattle. After pubescence, the CtM cattle harbor distinct ileal microbiota dominated by the family Peptostreptococcaceae and exhibit distinct serum and muscle amino acid profiles (i.e., highly abundant branched-chain amino acids), with increased extra- and intramuscular fat storage. We also evaluate the causative factor(s) that underpin the alteration of the intestinal microbiota and host metabolic phenotype in response to hypogonadism. Castration of male mice phenocopies both the intestinal microbial alterations and obese-prone metabolism observed in cattle. Antibiotic treatment and fecal microbiota transplantation experiments in a mouse model confirm that the intestinal microbial alterations associated with hypogonadism are a key contributor to the obese phenotype in the CtM animals. Collectively, targeting the gut microbiota is a potential therapeutic strategy for the treatment of both hypogonadism and obesity.


Assuntos
Adiposidade , Microbioma Gastrointestinal , Animais , Bovinos , Transplante de Microbiota Fecal , Feminino , Masculino , Camundongos , Obesidade , Orquiectomia
3.
J Neuroradiol ; 50(1): 54-58, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35364131

RESUMO

PURPOSE: Antiplatelet maintenance after stent-assisted coil embolization (SACE) is generally considered essential to avoid post-procedural thromboembolic complications. However, there is still debate as to whether it is safe to discontinue antiplatelet drugs after SACE or when is the best time to do so. We investigate herein the clinical outcomes experienced by patients who discontinue antiplatelet agents after SACE. METHODS: From a prospective database, we retrieved the data for 120 consecutive patients (harboring 130 aneurysms) in whom antiplatelet agents were discontinued after SACE between January 2010 and December 2019. We defined thromboembolic complications associated with discontinuation as neurologic or radiographic ischemia that occurred within 6 months of discontinuation of antiplatelet agents; the lesion was required to be correlated with the stented artery. RESULTS: The mean time of discontinuation of antiplatelet medication was 31.4 ± 18.3 months after SACE (median, 26 months). The majority of patients stopped antiplatelet medication between 18 and 36 months after SACE (74 patients, 61.6%). Laser-cut closed-cell stent was most commonly applied in 91 aneurysms (70.0%), followed by braided closed-cell (n=29; 22.3 %) and laser-cut open-cell stent 10 (7.7 %). No patients experienced cerebral ischemia related to discontinuation of antiplatelet medication. CONCLUSION: Our preliminary study suggests that it may be safe to discontinue antiplatelet medication after SACE in patients at low risk for ischemia. The optimal time to discontinue might be around 18 to 36 months after SACE. Large cohort-based studies or randomized clinical trials are warranted to confirm these results.


Assuntos
Isquemia Encefálica , Embolização Terapêutica , Aneurisma Intracraniano , Tromboembolia , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Aneurisma Intracraniano/terapia , Aneurisma Intracraniano/tratamento farmacológico , Stents/efeitos adversos , Estudos de Coortes , Isquemia Encefálica/etiologia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Estudos Retrospectivos , Resultado do Tratamento
4.
Small ; 18(48): e2205057, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36269881

RESUMO

Flat metasurfaces with subwavelength meta-atoms can be designed to manipulate the electromagnetic parameters of incident light and enable unusual light-matter interactions. Although hydrogel-based metasurfaces have the potential to control optical properties dynamically in response to environmental conditions, the pattern resolution of these surfaces has been limited to microscale features or larger, limiting capabilities at the nanoscale, and precluding effective use in metamaterials. This paper reports a general approach to developing tunable plasmonic metasurfaces with hydrogel meta-atoms at the subwavelength scale. Periodic arrays of hydrogel nanodots with continuously tunable diameters are fabricated on silver substrates, resulting in humidity-responsive surface plasmon polaritons (SPPs) at the nanostructure-metal interfaces. The peaks of the SPPs are controlled reversibly by absorbing or releasing water within the hydrogel matrix, the matrix-generated plasmonic color rendering in the visible spectrum. This work demonstrates that metasurfaces designed with these spatially patterned nanodots of varying sizes benefit applications in anti-counterfeiting and generate multicolored displays with single-nanodot resolution. Furthermore, this work shows system versatility exhibited by broadband beam-steering on a phase modulator consisting of hydrogel supercell units in which the size variations of constituent hydrogel nanostructures engineer the wavefront of reflected light from the metasurface.


Assuntos
Hidrogéis , Nanoestruturas , Prata , Umidade , Água
5.
Artigo em Inglês | MEDLINE | ID: mdl-35929988

RESUMO

A novel bacterium, designated strain JHSY0214T, was isolated from the gut of a Korean limpet, Cellana toreuma. Cells of strain JHSY0214T were Gram-stain-negative, strictly aerobic, yellow-pigmented, non-spore-forming, non-motile and showed a rod-coccus growth cycle. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain belonged to the genus Parasphingorhabdus, and was most closely related to Parasphingorhabdus litoris KCTC 12764T (98.71 %). Strain JHSY0214T had two fluoroquinolone-resistance genes and seven multidrug-resistance efflux pump genes, but did not have beta-lactamase genes and zinc resistance genes compared with P. litoris KCTC 12764T. Strain JHSY0214T grew optimally at 30 °C, pH 7.0 and in the presence of 2 % (w/v) NaCl. The predominant cellular fatty acids of strain JHSY0214T were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c; 41.2 %), summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 21 %) and C16 : 0 (18.9 %). The major isoprenoid quinone was ubiquinone-10. The major polar lipids were sphingoglycolipid and phosphatidylethanolamine. The genomic DNA G+C content was 52.8 mol%. Based on phylogenetic, genotypic and phenotypic data, strain JHSY0214T represents a novel species of the genus Parasphingorhabdus, for which the name Parasphingorhabdus cellanae is proposed. The type strain is JHSY0214T (=KCTC 82387T=DSM 112279T).


Assuntos
Ácidos Graxos , Gastrópodes , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
6.
Int J Syst Evol Microbiol ; 71(12)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34870576

RESUMO

Cultivation and isolation of gut bacteria are necessary for understanding their role in the intestinal ecosystem. We isolated a novel bacterium, designated strain BG01T, from the faeces of a patient with Crohn's disease. Strain BG01T was a strictly anaerobic, rod-shaped, Gram-variable and endospore-forming bacterium. Strain BG01T possessed C12 : 0, C18 : 0 dimethyl aldehyde (DMA) and C18 : 1 ω9c DMA as predominant cellular fatty acids and meso-diaminopimelic acid as a diagnostic diamino acid. Strain BG01T grew at 15-45 °C (optimum, 37 °C), with 0-4 % (w/v) NaCl (optimum, 0-1 %), at pH 6-10 (optimum, pH 7) and was resistant to bile salt, but not to ampicillin, metronidazole, vancomycin and cefoperazone. Butyrate, propionate, oxalacetate and fumarate were produced as fermentation end products from Gifu anaerobic medium broth. Strain BG01T showed 97.7 % 16S rRNA gene sequence similarity, and 92.0 and 48.5 % of average nucleotide identity and digital DNA-DNA hybridization values, respectively, with Anaerostipes caccae KCTC 15019T. Genomic analysis indicated that strain BG01T had a butyrate-producing pathway. The genomic G+C content of the strain was 43.5 mol%. Results of the phenotypic, phylogenetic and genotypic analyses indicated that strain BG01T represents a novel butyrate-producing species of the genus Anaerostipes, for which the name Anaerostipes hominis sp. nov. is proposed. The type strain is BG01T (=KCTC 15617T=JCM 32275T).


Assuntos
Butiratos/metabolismo , Doença de Crohn , Firmicutes/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Doença de Crohn/microbiologia , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Firmicutes/isolamento & purificação , Humanos , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Artigo em Inglês | MEDLINE | ID: mdl-34296988

RESUMO

A novel Gram-stain-negative, aerobic, rod-shaped bacterium with a single polar flagellum, designated strain 2T18T, was isolated from the gut of the freshwater mussel Anodonta arcaeformis collected in the Republic of Korea. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belonged to the genus Chitinibacter. Strain 2T18T formed a monophyletic clade with Chitinibacter fontanus KCTC 42982T, C. tainanensis KACC 11706T and C. alvei KCTC 23839T, with sequence similarities of 98.5, 98.4 and 95.9 %, respectively. Strain 2T18T exhibited optimal growth at 30 °C, at pH 8 and with 0.5 % (w/v) NaCl. The major isoprenoid quinone was ubiquinone-8 (Q-8). The predominant fatty acids were summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c) and C16 : 0. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified lipid, three unidentified phospholipids and two unidentified aminophospholipids. The G+C content of the genomic DNA was 50.6 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strains 2T18T and C. fontanus KCTC 42982T were below the thresholds used for the delineation of a novel species. Based on the phylogenetic, phenotypic, chemotaxonomic and genotypic characteristics, strain 2T18T represents a novel species of the genus Chitinibacter, for which the name Chitinibacter bivalviorum sp. nov. is proposed. The type strain is 2T18T (=KCTC 72821T=CCUG 74764T).


Assuntos
Anodonta/microbiologia , Betaproteobacteria/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Betaproteobacteria/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Água Doce , Trato Gastrointestinal/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-33886445

RESUMO

A polyphasic taxonomic approach was used to characterize two novel bacterial strains, designated as HDW11T and HDW19T, isolated from intestine samples of the dark diving beetle Hydrophilus acuminatus and the diving beetle Cybister lewisianus, respectively. Both isolates were Gram-stain-positive, facultatively anaerobic and non-motile. Strain HDW11T grew optimally at 30 °C, pH 8 and in the presence of 1% (w/v) NaCl. Strain HDW19T grew optimally at 25 °C, pH 7 and in the presence of 0.3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences and genome sequences revealed that strain HDW11T is a member of the genus Brevilactibacter and is closely related to Brevilactibacter flavus VG341T [with 97.9% 16S rRNA sequence identity and 79.1% average nucleotide identity (ANI)], and that strain HDW19T belongs to the genus Weissella and is closely related to W. koreensis KCTC 3621T (with 98.9% 16S rRNA sequence identity and 79.5% ANI). The major cellular fatty acids of strains HDW11T and HDW19T were C18:1 ω9c and anteiso-C15:0, respectively. The sole respiratory quinone of strain HDW11T was MK-9 (H4). The major polar lipid components of strain HDW11T were diphosphatidylglycerol and phosphatidylglycerol, and the major polar lipid component of strain HDW19T was diphosphatidylglycerol. The genomic DNA G+C content of strains HDW11T and HDW19T were 72.1 and 37.2 mol%, respectively. The results of phylogenetic, phenotypic, chemotaxonomic and genotypic analyses suggest that strain HDW11T represents a novel species within the genus Brevilactibacter, and that strain HDW19T represents a novel species within the genus Weissella. We propose the name Brevilactibacter coleopterorum sp. nov. for strain HDW11T (=KACC 21335T=KCTC 49320T=JCM 33680T) and the name Weissella coleopterorum for strain HDW19T (=KACC 21347T=KCTC 43114T=JCM 33684T).


Assuntos
Besouros/microbiologia , Intestinos/microbiologia , Filogenia , Propionibacteriaceae/classificação , Weissella/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Besouros/classificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Weissella/isolamento & purificação
9.
Artigo em Inglês | MEDLINE | ID: mdl-33289624

RESUMO

A polyphasic taxonomic approach was used to characterize a novel bacterium, designated as strain HDW20T, isolated from the intestine of the dark diving beetle Hydrophilus acuminatus. The isolate was Gram-stain-positive, facultatively anaerobic, non-motile, coccus-shaped, and formed pale orange colonies. Phylogenetic analysis based on 16S rRNA gene sequences and genome sequences showed that the isolate belonged to the genus Tessaracoccus in the phylum Actinobacteria and was closely related to T. flavescens SST-39T, T. defluvii JCM 17540T, and T. aquimaris NSG39T, with the highest 16S rRNA gene sequence similarity of 98.5 % and a highest average nucleotide identity (ANI) value of 80.6 %. The major cellular fatty acids were C18 : 1 ω9c and anteiso-C15 : 0. The main respiratory quinone was MK-9 (H4). The major polar lipid components were phosphatidylglycerol and diphosphatidylglycerol. The genomic DNA G+C content was 69.0 %. The isolate contains ʟʟ-diaminopimelic acid, ʟ-alanine, and ʟ-lysine as amino acid components, and ribose, glucose, and galactose as sugar components of the cell wall peptidoglycan. The results of phylogenetic, phenotypic, chemotaxonomic, and genotypic analyses suggested that strain HDW20T represents a novel species within the genus Tessaracoccus. We propose the name Tessaracoccus coleopterorum sp. nov. The type strain is HDW20T (=KACC 21348T=KCTC 49324T=JCM 33674T).


Assuntos
Besouros/microbiologia , Intestinos/microbiologia , Filogenia , Propionibacteriaceae/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , Pigmentação , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , República da Coreia , Rios , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Int J Syst Evol Microbiol ; 70(10): 5439-5444, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32886601

RESUMO

A novel Gram-stain-positive, non-motile, non-spore-forming, coccobacillus-shaped, strictly aerobic bacterium, designated strain H23T48T, was isolated from the faecal sample of an oriental stork collected from the Seoul Grand Park Zoo in Seoul, Republic of Korea. Optimal growth of strain H23T48T was observed at 30-37 °C, pH 8 and with 3 % (w/v) NaCl. 16S rRNA gene sequence-based phylogenetic analysis revealed that strain H23T48T was closely related to the genus Flaviflexus, with 97.0 and 96.7 % sequence similarities to Flaviflexus salsibiostraticola EBR4-1-2T and Flaviflexus huanghaiensis H5T, respectively. Strain H23T48T possessed MK-9(H4) as the major menaquinone and C16 : 0 (42.4 %), C18 : 1 ω9c (31.3 %) and C14 : 0 (17.7 %) as the major cellular fatty acids. The polar lipids included phosphatidylglycerol, two unidentified lipids, six unidentified phospholipids and two unidentified glycophospholipids. The amino acid composition of the cell-wall peptidoglycan was l-alanine, l-lysine, d-glutamic acid, l-aspartic acid and glycine. The genomic G+C content of strain H23T48T is 59.5 mol% and the average nucleotide identity value between H23T48T and F. salsibiostraticola KCT C33148T (=EBR4-1-2T) is 75.5 %. Based on the obtained data, strain H23T48T represents a novel species of the genus Flaviflexus, for which the name Flaviflexus ciconiae sp. nov. is proposed. The type strain is H23T48T (=KCTC 49253T=JCM 33282T).


Assuntos
Actinomycetaceae/classificação , Aves/microbiologia , Filogenia , Actinomycetaceae/isolamento & purificação , Animais , Animais de Zoológico/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Int J Syst Evol Microbiol ; 70(5): 3247-3254, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375988

RESUMO

A novel, Gram-stain-positive, non-spore-forming, facultatively anaerobic bacterium, designated strain H21T32T, was isolated from the faeces of an Oriental stork, Ciconia boyciana. Cells formed cocci grouped in pairs, tetrads or conglomerates, and colonies on solid medium were pale yellow. Strain H21T32T belonged to the genus Jeotgalibaca, family Carnobacteriaceae, order Lactobacillales and class Bacilli. The 16S rRNA gene sequences of the strain showed 97.06-97.34, 96.17-96.31 and 95.93-96.07 % similarity to the type strains of Jeotgalibaca arthritidis, J. porci and J. dankookensis, respectively. The strain grew at 10-37 °C (optimum temperature: 30 °C), with 0-7 % (w/v) NaCl (optimum salinity: 0.5 %) and at pH 7-9 (optimum pH: 8). The main cellular fatty acids were C16 : 1 ω9c, C18 : 1 ω9c and C16 : 0. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. Respiratory quinones were not detected. Sugar components of the peptidoglycan were rhamnose, ribose and glucose. Amino acid components of the cell wall were l-alanine, d-glucose, l-lysine, glycine and aspartic acid. The DNA G+C content of the strain was 37.1 mol%. Average nucleotide identity between strain H21T32T and J. arthritidis CECT 9157T was 77.02 %, confirming that strain H21T32T represents a novel species of the genus Jeotgalibaca, for which the name Jeotgalibaca ciconiae sp. nov. is proposed. The type strain is H21T32T (=KCTC 33991T=JCM 33222T).


Assuntos
Aves/microbiologia , Carnobacteriaceae/classificação , Fezes/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Carnobacteriaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Peptidoglicano/química , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
12.
Int J Syst Evol Microbiol ; 70(4): 2305-2311, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32038006

RESUMO

A novel Gram-negative, obligately aerobic, rod-shaped and non-motile bacterium, designated strain K13M18T, was isolated from the intestinal tract of a Korean indigenous fish, oily bitterling (Acheilognathus koreensis). Strain K13M18T formed creamy-pink colonies on a marine agar plate. Results of phylogenetic analysis based on the 16S rRNA gene sequence similarity indicated that strain K13M18T was most closely related to Tabrizicola sediminis DRYC-M-16T, sharing 97.62 % similarity with that strain. Strain K13M18T belonged to the genus Tabrizicola, which formed a cluster with Tabrizicola aquatica RCRI19T, Tabrizicola fusiformis SY72T, Tabrizicola sediminis DRYC-M-16T and Tabrizicola alkalilacus DJCT in a phylogenetic tree based on the 16S rRNA gene sequences. Strain K13M18T grown optimally in 0 % (w/v) NaCl, at pH 7 and 30 °C, in a marine broth medium. The predominant cellular fatty acids were C18 : 1 ω7c and C18 : 1 ω6c. The major respiratory isoprenoid quinone was ubiquinone Q-10. Polar lipids of strain K13M18T contained phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, diphosphatidylglycerol, six unidentified aminophospholipids, one unidentified aminolipid and an unidentified lipid. Based on genome sequencing, the DNA G+C content of strain K13M18T was 64.08 mol %, with an average nucleotide identity value, calculated by a comparative genomic analysis of strains K13M18T and T. sediminis DRYC-M-16T, of 74.82 %. Based on the phylogenetic, genotypic, and phenotypic information, strain K13M18T is proposed to be a novel species of the genus Tabrizicola. The type strain is K13M18T (=KCTC 62659T=JCM 33230T).


Assuntos
Peixes/microbiologia , Trato Gastrointestinal/microbiologia , Filogenia , Rhodobacteraceae/classificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Água Doce , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , República da Coreia , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
13.
Int J Syst Evol Microbiol ; 70(1): 499-504, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31613737

RESUMO

A novel Gram-stain-negative, aerobic, rod-shaped, reddish-orange-coloured, gliding bacterial strain, designated L12M1T, was isolated from the gut of the Korean scallop, Patinopecten yessoensis. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain L12M1T formed a monophyletic clade with the strains in the genus Flammeovirga and showed highest 16S rRNA gene sequence similarity to Flammeovirga kamogawensis YS10T (98.66 %). The major cellular fatty acids of strain L12M1T were iso-C15 : 0 and C20 : 4ω6,9,12,15c. The predominant isoprenoid quinone was MK-7. The major polyamines were spermidine, cadaverine and the minor polyamine was putrescine. The DNA G+C content was 32.1 mol%. The phylogenetic, phenotypic, biochemical, chemotaxonomic and genotypic results indicated that strain L12M1T represents a novel species of the genus Flammeovirga, for which the name Flammeovirga pectinis sp. nov. is proposed. The type strain is L12M1T (=KCTC 62750T=JCM 33169T).


Assuntos
Bacteroidetes/classificação , Pectinidae/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Pigmentação , Poliaminas/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
J Adolesc ; 85: 126-134, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33227598

RESUMO

INTRODUCTION: For the past few decades, numerous theoretical perspectives have predicted a negative association between adolescent sexual debut and the probability of college entrance. The present article extends the literature by using nationally representative longitudinal data from South Korea to assess these perspectives. METHODS: Drawing on longitudinal data from South Korea, this article examined the impact of becoming sexually active between 8th and 12th grades on the probability of college entrance. We controlled for a wide array of confounding variables by using logit models that account for longitudinal attrition and school-based sampling design. RESULTS: Analytical results showed that the initiation of sexual intercourse during adolescence predicted a statistically significant decrease in the probability of college entrance for both boys and girls. Gender-specific analyses suggested that, on average, sexual debut in adolescence was associated with a decrease of 10.3 percentage points in the probability of college entrance for boys and a decrease of 14.7 percentage points for girls. CONCLUSIONS: These findings strongly support the theoretical perspectives of age norm theory and sexual double standards in South Korea, where strictly conservative attitudes toward sexuality and sexual behaviors are dominant.


Assuntos
Sucesso Acadêmico , Comportamento do Adolescente/fisiologia , Comportamento Sexual/psicologia , Adolescente , Feminino , Equidade de Gênero , Humanos , Estudos Longitudinais , Masculino , República da Coreia , Universidades
15.
Artigo em Inglês | MEDLINE | ID: mdl-33616519

RESUMO

A novel Gram-stain-negative, coccus-shaped, aerobic and motile bacterial strain, designated S12M18T, was isolated from the gut of the Korean turban shell, Turbo cornutus. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain S12M18T belonged to the genus Pseudorhodobacter and had the highest 16S rRNA gene sequence similarity twith Pseudorhodobacter aquimaris HDW-19T (98.63 %). The phylogenomic tree congruently verified that strain S12M18T occupies a taxonomic position within the genus Pseudorhodobacter. The OrthoANIu value between strain S12M18T and P. aquimaris HDW-19T was 87.22 %. The major cellular fatty acid of strain S12M18T was summed feature 8 (C18 : 1 ω7c or C18 : 1 ω6c). The major components of the polar lipids were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The predominant isoprenoid quinone was Q-10. The DNA G+C content was 57.8 mol%. The polyphasic analyses indicated that strain S12M18T represents a novel species of the genus Pseudorhodobacter, for which the name Pseudorhodobacter turbinis sp. nov. is proposed. The type strain is S12M18T (=KCTC 62742T=JCM 33168T).

16.
Int J Syst Evol Microbiol ; 69(9): 2948-2953, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31282852

RESUMO

A novel Gram-stain-negative, facultatively anaerobic, non-motile, non-violet-pigmented, rod-shaped bacterium, designated strain H11R3T, was isolated from the feces of Oriental stork, Ciconia boyciana, collected from Seoul Grand Park Zoo, Republic of Korea. Phylogenetic analysis of the 16S rRNA gene sequence revealed that H11R3T formed a monophyletic clade with Iodobacter fluviatilisDSM 3764T, Iodobacter arcticusDSM 100243T, and Iodobacter limnosediminisDSM 103822T, with sequence similarities of 98.8, 98.6 and 98.4 %, respectively. H11R3T grew optimally at 15 °C, pH 8, with 0.5 % (w/v) NaCl. The predominant isoprenoid quinone was ubiquinone-8 (Q-8), and polar lipids included phosphatidylethanolamine, three unidentified lipids, four unidentified phospholipids, and two unidentified aminophospholipids. The major fatty acids were summed feature 3 and C16 : 0, and the DNA G+C content of the genome is 48.0 mol%. The average nucleotide identity (ANI) value between strains H11R3T and I. fluviatilis NCTC 11159T (=DSM 3764T) is 83.7 %. On the basis of phenotypic, genotypic, phylogenetic and chemotaxonomic characteristics, strain H11R3T represents a novel species of the genus Iodobacter for which the name Iodobacterciconiae sp. nov. is proposed. The type strain is H11R3T (=KCTC 62666T=JCM 33283T).


Assuntos
Betaproteobacteria/classificação , Aves/microbiologia , Filogenia , Animais , Animais de Zoológico/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Betaproteobacteria/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
17.
Int J Syst Evol Microbiol ; 69(10): 3148-3154, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385778

RESUMO

A novel Gram-stain-negative, non-spore-forming, obligate aerobic, motile, rod-shaped, and flagellated bacterium, designated S11R28T, was isolated from the intestinal tract of a Korean shiner, Coreoleuciscus splendidus. Based on 16S rRNA gene sequences, strain S11R28T was identified as member of the genus Undibacterium in class Betaproteobacteria, and was closely related to Undibacterium parvum DSM 23061T (98.49 %). The isolate grew at 4-25 °C, pH 6-9, with 0 % (w/v) NaCl, and grew optimally at 20 °C, pH 8, in the absence of NaCl. The main cellular fatty acids were C16 : 0 and summed features 3 (C16 : 1ω7c and/or C16 : 1ω6c). The strain possessed diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine as predominant polar lipids, and ubiquinone Q-8 as a respiratory quinone. The polyamine profile composed of 2-hydroxyputrescine, spermidine, putrescine, and benzoic acid. A genomic DNA G+C content was 51.4 mol%. The average nucleotide identity between strains S11R28T and U. parvum DSM 23061T was 78.66 %. Thus, Undibacterium piscinae can be considered a novel species within the genus Undibacterium with the type strain S11R28T (=KCTC 62668T=JCM 33224T).


Assuntos
Cyprinidae/microbiologia , Intestinos/microbiologia , Oxalobacteraceae/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oxalobacteraceae/isolamento & purificação , Fosfolipídeos/química , Poliaminas/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
18.
Infect Immun ; 86(4)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29426044

RESUMO

Abnormalities in the human microbiota are associated with the etiology of allergic diseases. Although disease site-specific microbiota may be associated with disease pathophysiology, the role of the nasal microbiota is unclear. We sought to characterize the microbiota of the site of allergic rhinitis, the inferior turbinate, in subjects with allergic rhinitis (n = 20) and healthy controls (n = 12) and to examine the relationship of mucosal microbiota with disease occurrence, sensitized allergen number, and allergen-specific and total IgE levels. Microbial dysbiosis correlated significantly with total IgE levels representing combined allergic responses but not with disease occurrence, the number of sensitized allergens, or house dust mite allergen-specific IgE levels. Compared to the populations in individuals with low total IgE levels (group IgElow), low microbial biodiversity with a high relative abundance of Firmicutes phylum (Staphylococcus aureus) and a low relative abundance of Actinobacteria phylum (Propionibacterium acnes) was observed in individuals with high total serum IgE levels (group IgEhigh). Phylogeny-based microbial functional potential predicted by the 16S rRNA gene indicated an increase in signal transduction-related genes and a decrease in energy metabolism-related genes in group IgEhigh as shown in the microbial features with atopic and/or inflammatory diseases. Thus, dysbiosis of the inferior turbinate mucosa microbiota, particularly an increase in S. aureus and a decrease in P. acnes, is linked to high total IgE levels in allergic rhinitis, suggesting that inferior turbinate microbiota may be affected by accumulated allergic responses against sensitized allergens and that site-specific microbial alterations play a potential role in disease pathophysiology.


Assuntos
Disbiose , Imunoglobulina E/imunologia , Microbiota , Mucosa Nasal/microbiologia , Rinite Alérgica/imunologia , Rinite Alérgica/microbiologia , Conchas Nasais/microbiologia , Alérgenos/imunologia , Biodiversidade , Biomarcadores , Estudos de Casos e Controles , Feminino , Humanos , Imunização , Imunoglobulina E/sangue , Masculino , RNA Ribossômico 16S , Análise de Sequência de DNA
19.
Int J Syst Evol Microbiol ; 68(4): 1065-1072, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29458549

RESUMO

A novel coccus-shaped, Gram-stain-positive, non-motile and aerobic bacterium, designated strain NSG39T, was isolated from the intestine of a Korean rockfish, Sebastes schlegelii. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the newly isolated strain NSG39T was closely related to Tessaracoccus flavus RP1T (98.0 %). The isolate grew at 15-37 °C, pH 7-9 and 0-4 % (w/v) salinity, with optimal growth at 30 °C, pH 8 and 0 % (w/v) salinity. The cell wall of the organism contained ll-diaminopimelic acid as a diagnostic diamino acid, and ribose, mannose, glucose and galactose as diagnostic sugars. The polar lipid comprised diphosphatidylglycerol, phosphatidylglycerol, three glycolipids and four unidentified polar lipids. The major cellular fatty acid was anteiso-C15 : 0 (47.2 %). The major menaquinone was MK-9 (H4). The DNA G+C content of the isolate was 68.8 mol%. The genome-based orthologous average nucleotide identity value for strain NSG39T and T. flavus RP1T was 76.6 %. Based on the phylogenetic analysis and its biological characteristics, strain NSG39T is considered to represent a novel species of the genus Tessaracoccus, for which the name Tessaracoccus aquimaris is proposed. The type strain is NSG39T (=KACC 17540T=JCM 19289T).


Assuntos
Intestinos/microbiologia , Perciformes/microbiologia , Filogenia , Propionibacteriaceae/classificação , Animais , Aquicultura , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Glicolipídeos/química , Lagoas , Propionibacteriaceae/genética , Propionibacteriaceae/isolamento & purificação , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
20.
Int J Syst Evol Microbiol ; 68(4): 1059-1064, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29458493

RESUMO

A strictly anaerobic, Gram-stain-positive, non-motile and coccoid- or oval-shaped bacterium, designated strain KB1T, was isolated from a faecal sample of a patient with diverticulitis in South Korea. Degeneracies in the 16S rRNA gene sequence of strain KB1T were resolved by cloning, which yielded five different sequences with heterogeneity. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain KB1T formed a monophyletic branch with species in the genus Blautia, with highest sequence similarity to the type strain of Blautia producta (97.7-98.9 %), followed by Blautia coccoides (97.5-98.1 %). Strain KB1T was able to grow at temperatures of between 15 and 42 °C, with optimal growth at 37 °C, and in the presence of 20 % dehydrated bile. Acetic acid, succinic acid, lactic acid and fumaric acid were produced by strain KB1T from Gifu anaerobic medium broth as metabolic fermentation end-products. The major cellular fatty acids of strain KB1T were C14 : 0, C16 : 0 and C16 : 0 dimethyl aldehyde. The DNA G+C content was 46.3 mol%. The average nucleotide identity value between strain KB1T and the type strain of B. producta was 84.1 %. On the basis of polyphasic analysis, strain KB1T represents a novel species in the genus Blautia, for which the name Blautia hominis sp. nov. is proposed. The type strain is KB1T (=KCTC 15618T=JCM 32276T).


Assuntos
Clostridiales/classificação , Fezes/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Clostridiales/genética , Clostridiales/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/análise , Fermentação , Humanos , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
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