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1.
ACS Appl Mater Interfaces ; 16(21): 27728-27740, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38758746

RESUMO

In recent decades, extensive research has been directed toward mitigating microbial contamination and preventing biofilm formation. However, many conventional antibiofilm methods rely on hazardous and toxic substances, neglecting potential risks to human health and the environment. Moreover, these approaches often rely on single-strategy mechanisms, utilizing either bactericidal or fouling-resistant agents, which have shown limited efficacy in long-term biofilm suppression. In this study, we propose an efficient and sustainable biofilm-resistant slippery hybrid slippery composite. This composite integrates nontoxic and environmentally friendly materials including chitosan, silicone oil-infused polydimethylsiloxane, and mesoporous silica nanoparticles in a synergistic manner. Leveraging the bacteria-killing properties of chitosan and the antifouling capabilities of the silicone oil layer, the hybrid composite exhibits robust antibiofilm performance against both Gram-positive and Gram-negative bacteria. Furthermore, the inclusion of mesoporous silica nanoparticles enhances the oil absorption capacity and self-replenishing properties, ensuring exceptional biofilm inhibition even under harsh conditions such as exposure to high shear flow and prolonged incubation (7 days). This approach offers promising prospects for developing effective biofilm-resistant materials with a reduced environmental impact and improved long-term performance.


Assuntos
Antibacterianos , Biofilmes , Quitosana , Dimetilpolisiloxanos , Nanopartículas , Dióxido de Silício , Biofilmes/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Nanopartículas/química , Antibacterianos/farmacologia , Antibacterianos/química , Porosidade , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacologia , Testes de Sensibilidade Microbiana
2.
Korean J Fam Med ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773693

RESUMO

Background: Atherosclerotic cardiovascular disease (ASCVD) is a major health concern, and lipoprotein(a) (Lp(a)) is an independent risk factor. However, there is limited evidence regarding Lp(a) and the risk of ASCVD in Asian populations. This study aimed to assess the predictive value of changes in coronary artery calcification (CAC) for ASCVD risk associated with Lp(a) level. Methods: Participants (n=2,750) were grouped according to their Lp(a) levels, and the association between Lp(a) and CAC progression was examined. CAC progression was defined as the occurrence of incident CAC or a difference ≥2.5 between the square root (√) of baseline and follow-up coronary artery calcium scores (CACSs) (Δ√transformed CACS). To adjust for differences in follow-up periods, Δ√transformed CACS was divided by the follow- up period (in years). Results: Over an average follow-up of 3.07 years, 18.98% of participants experienced CAC progression. Those with disease progression had notably higher Lp(a) levels. Higher Lp(a) tertiles correlated with increased baseline and follow-up CACS, CAC progression (%), and Δ√transformed CACS. Even after adjustment, higher Lp(a) levels were associated with CAC progression. However, annualized Δ√transformed CACS analysis yielded no significant results. Conclusion: This study demonstrated an association between elevated Lp(a) levels and CAC progression in a general population without ASCVD. However, longer-term follow-up studies are needed to obtain meaningful results regarding CAC progression. Further research is necessary to utilize Lp(a) level as a predictor of cardiovascular disease and to establish clinically relevant thresholds specific to the Korean population.

3.
Animals (Basel) ; 13(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37760246

RESUMO

Canine lymphoma (CL) is one of the most common malignant tumors in dogs. The cause of CL remains unclear. Genetic mutations that have been suggested as possible causes of CL are not fully understood. Whole-exome sequencing (WES) is a time- and cost-effective method for detecting genetic variants targeting only the protein-coding regions (exons) that are part of the entire genome region. A total of eight patients with B-cell lymphomas were recruited, and WES analysis was performed on whole blood and lymph node aspirate samples from each patient. A total of 17 somatic variants (GOLIM4, ITM2B, STN1, UNC79, PLEKHG4, BRF1, ENSCAFG00845007156, SEMA6B, DSC1, TNFAIP1, MYLK3, WAPL, ADORA2B, LOXHD1, GP6, AZIN1, and NCSTN) with moderate to high impact were identified by WES analysis. Through a Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of 17 genes with somatic mutations, a total of 16 pathways were identified. Overall, the somatic mutations identified in this study suggest novel candidate mutations for CL, and further studies are needed to confirm the role of these mutations.

4.
Adv Mater ; 35(43): e2204872, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36036368

RESUMO

Halide perovskites have emerged as promising candidates for various applications, such as photovoltaic, optoelectronic and thermoelectric applications. The knowledge of the thermal transport of halide perovskites is essential for enhancing the device performance for these applications and improving the understanding of heat transport in complicated material systems with atomic disorders. In this work, the current understanding of the experimentally and theoretically obtained thermal transport properties of halide perovskites is reviewed. This study comprehensively examines the reported thermal conductivity of methylammonium lead iodide, which is a prototype material, and provides theoretical frameworks for its lattice vibrational properties. The frameworks and discussions are extended to other halide perovskites and derivative structures. The implications for device applications, such as solar cells and thermoelectrics, are discussed.

5.
ACS Appl Mater Interfaces ; 14(34): 39478-39488, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35959590

RESUMO

Over the past few decades, extensive research efforts have been devoted to developing surfaces with unique functionalities, such as controlled wettability, antibiofouling, antifogging, and anti-icing behavior, for applications in a wide range of fields, including biomedical devices, optical instruments, microfluidics, and energy conservation and harvesting. However, many of the previously reported approaches have limitations with regard to eco-friendliness, multifunctionality, long-term stability and efficacy, and cost effectiveness. Herein, we propose a scalable bifunctional surface that simultaneously exhibits excellent antifogging and antibiofouling properties based on the synergistic integration of an eco-friendly and bio-friendly polyethylene glycol (PEG) hydrogel, oleamide (OA), and nanoscale architectures in a single flexible platform. We demonstrate that the PEG-OA-nanostructure hybrid exhibits excellent antifogging performance owing to its enhanced water absorption and spreading properties. We further show that the triple hybrid exhibits notable biofilm resistance without the use of toxic biocides or chemicals by integrating the "fouling-resistant" mechanism of the PEG hydrogel, the "fouling-release" mechanism of OA, and the "foulant-killing" mechanism of the nanostructures.

6.
Forensic Sci Int ; 338: 111385, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35863161

RESUMO

A wide variety of new synthetic cannabinoids have emerged around the world in recent years, and because of this rapid emergence, the detection and monitoring of this class of abused drugs remain a challenge. In this study, a new cannabimimetic indazole-3-carboxamide derivative, N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)- 5-bromo-1 H-indazole-3-carboxamide, was identified from seized e-cigarette liquid samples and newly named as ADB-BRINACA by referring to the names of other known indazole-class synthetic cannabinoids. Structure identification was accomplished based on gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography-high resolution quadrupole mass spectrometry (HPLC-QTOF-MS/MS), and nuclear magnetic resonance spectrometry (NMR). The concentration range of ADB-BRINACA in six e-cigarette liquid samples was found to be 2228-4203 mg/L using ERETIC 2, a quantitative NMR method, which is advantageous in the absence of a reference material. As there have been no chemical or pharmaceutical reports on ADB-BRINACA until now, this is the first report presenting a comprehensive analytical characterization of ADB-BRINACA.


Assuntos
Canabinoides , Sistemas Eletrônicos de Liberação de Nicotina , Canabinoides/análise , Indazóis/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Massas em Tandem/métodos
7.
J Microbiol ; 60(5): 533-549, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35362897

RESUMO

The disruption of the human gut microbiota has been linked to host health conditions, including various diseases. However, no reliable index for measuring and predicting a healthy microbiome is currently available. Here, the sequencing data of 1,663 Koreans were obtained from three independent studies. Furthermore, we pooled 3,490 samples from public databases and analyzed a total of 5,153 fecal samples. First, we analyzed Korean gut microbiome covariates to determine the influence of lifestyle on variation in the gut microbiota. Next, patterns of microbiota variations across geographical locations and disease statuses were confirmed using a global cohort and di-sease data. Based on comprehensive comparative analysis, we were able to define three enterotypes among Korean cohorts, namely, Prevotella type, Bacteroides type, and outlier type. By a thorough categorization of dysbiosis and the evaluation of microbial characteristics using multiple datasets, we identified a wide spectrum of accuracy levels in classifying health and disease states. Using the observed microbiome patterns, we devised an index named the gut microbiome index (GMI) that could consistently predict health conditions from human gut microbiome data. Compared to ecological metrics, the microbial marker index, and machine learning approaches, GMI distinguished between healthy and non-healthy individuals with a higher accuracy across various datasets. Thus, this study proposes a potential index to measure health status of gut microbiome that is verified from multiethnic data of various diseases, and we expect this model to facilitate further clinical application of gut microbiota data in future.


Assuntos
Microbioma Gastrointestinal , Disbiose , Fezes , Microbioma Gastrointestinal/genética , Humanos , Prevotella , República da Coreia/epidemiologia
8.
J Control Release ; 343: 57-65, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34763005

RESUMO

Dicer substrate RNA is an alternative gene silencing agent to canonical siRNA. Enhanced in vitro gene silencing can be achieved with RNA substrates by facilitating Ago2 loading of dsRNA after Dicer processing. However, the in vivo use of Dicer substrate RNA has been hindered by its instability and immunogenicity in the body due to the lack of proper chemical modification in the structure. Here, we report a universal chemical modification approach for Dicer substrate RNA nanostructures by optimizing protein-RNA interactions in the RNAi pathway. Proteins involved in the RNAi pathway were utilized for evaluating their recognition and binding of substrate RNA. It was found that conventional chemical modifications could severely affect the binding and processing of substrate RNA, consequently reducing RNAi activity. Protein-RNA interaction guided chemical modification was introduced to RNA nanostructures, and their gene silencing activity was assessed. The optimized RNA nanostructures showed excellent binding and processability with RNA binding proteins and offered the enhancement of in vivo EC50 up to 1/8 of its native form.


Assuntos
Inativação Gênica , Nanoestruturas , Interferência de RNA , RNA de Cadeia Dupla , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
9.
Scientometrics ; 126(5): 3697-3722, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776164

RESUMO

Firms today face rapidly changing and complex environments that managers and leaders must navigate carefully because confronting these changes is directly connected with success and failure in business. In particular, business leaders are adopting a new paradigm of planning, dynamic adaptive plans, which react adaptively to uncertainties by adjusting plans according to rapid changes in circumstances. However, these dynamic plans have been applied in larger-scale industries such as wastewater management in longer-range time frames. This paper follows the dynamic adaptive plan paradigm but transfers it to the technology management context with shorter-range action plans. Based on this new paradigm of risk management and technology planning, we propose a risk-adaptive technology roadmap (TRM) that can adapt to changing complex environments. First we identify risk by topic modeling based on futuristic data and then by sentiment analysis. Second, for the derived risks, we determine new and alternative plans by co-occurrence of risk-related keywords. Third, we convert an existing TRM to network topology with adaptive plans and construct a conditional probability table for the network. Finally, we estimate posterior probability and infer it by Bayesian network by adjusting plans depending on occurrence of risk events. Based on this posterior probability, we remap the paths in the previous TRM to new maps, and we apply our proposed approach to the field of artificial intelligence to validate its feasibility. Our research contributes to the possibility of using dynamic adaptive planning with technology as well as to increase the sustainability of technology roadmapping.

10.
Soft Matter ; 17(7): 1715-1723, 2021 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-33538288

RESUMO

Biofouling of tubular fluidic devices limits the stability, accuracy, and long-term uses of lab-on-a-chip systems. Healthcare-associated infection by biofilm formations on body-indwelling and extracorporeal tubular medical devices is also a major cause of mortality and morbidity in patients. Although diverse antifouling techniques have been developed to prevent bacterial contamination of fluidic devices based on antimicrobial materials or nanoscale architectures, they still have limitations in biocompatibility, long-term activity, and durability. In this study, a new conceptual tubular fluidic device model that can effectively suppress bacterial contamination based on dynamic surface motions without using bactericidal materials or nanostructures is proposed. The fluidic device is composed of a magneto-responsive multilayered composite. The composite tube can generate dynamic surface deformation with controlled geometries along its inner wall in response to a remote magnetic field. The magnetic field-derived surface wave induces the generation of vortices near the inner wall surface of the tube, enabling sweeping of bacterial cells from the surface. As a result, the dynamic composite tube could effectively prevent biofilm formation for an extended time of 14 days without surface modification with chemical substances or nanostructures.


Assuntos
Anti-Infecciosos , Incrustação Biológica , Nanoestruturas , Antibacterianos , Bactérias , Biofilmes , Incrustação Biológica/prevenção & controle , Humanos
11.
Food Sci Anim Resour ; 41(1): 153-163, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33506225

RESUMO

This study was conducted to examine the effects of starch noodles (dangmyeon; SNs) with different starch sources and porcine intestines (PIs) with different pH on the rehydration stability of Korean blood sausage (sundae). Mungbean SN3 and PI3 (pH 9.18) showed significantly higher values of 80.69%-91.67% and 79.66%-80.98%, respectively, regardless of the drying methods (hot air, vacuum and freeze drying) (p<0.05). A number of larger pores were observed only in the cross-section of the freeze dried SN and PI through SEM. SN2 (potato starch) and PI3 (pH 9.18) showed lower expansion (*ΔL 6.90 mm) and higher expansion ratio (*ΔL 26.29 mm), respectively, after rehydration of freeze dried sample (p<0.05). From the application of SN2 (potato starch) and PI (0.5%-2.0% Na-pyrophosphate) to freeze dried sundae manufacturing, higher rehydration stability of more than 91.5% was obtained. These results suggested that potato SN and treatment of PI with Na-pyrophosphate is useful for desirable rehydration stability of freeze dried sundae.

12.
Nanomedicine ; 27: 102194, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32278102

RESUMO

Recently, combination therapy has received much attention because of its highly therapeutic effect in various types of cancers. In particular, chemo-photodynamic combination therapy has been considered as an outstanding strategy. However, an abnormal increase in tumor angiogenesis caused by reactive oxygen species (ROS) generated during photodynamic therapy (PDT) has been reported. In this study, the complex of doxorubicin (DOX)-encapsulating anti-angiogenic small interfering RNA (siRNA) nanoparticle and chlorin e6 (Ce6)-encapsulating microbubble has been developed to suppress tumor angiogenesis. The first compartment, doxorubicin-encapsulating siRNA nanoparticle, was electrostatically coated using two biocompatible polymers to prevent the damage of genetic materials. The other part, Ce6-encapsulating microbubble, serves as an ultrasound-triggered local delivery system as well as a drug carrier. Both the in vitro and in vivo experimental results demonstrate successful inhibition of angiogenesis with a minimized damage of siRNAs caused by ROS as well as improved therapeutic effect by chemo-photodynamic-gene triple combination therapy using ultrasound-triggered local delivery.


Assuntos
Nanomedicina/tendências , Nanopartículas/química , Neovascularização Patológica/terapia , Fator A de Crescimento do Endotélio Vascular/genética , Linhagem Celular Tumoral , Clorofilídeos , Terapia Combinada , Doxorrubicina/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Tratamento Farmacológico/tendências , Humanos , Microbolhas , Neovascularização Patológica/diagnóstico por imagem , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Fotoquimioterapia/tendências , Porfirinas/química , Porfirinas/farmacologia , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ultrassonografia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
13.
Psychiatr Psychol Law ; 27(5): 912-923, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33841023

RESUMO

We compared the predictive validity of Psychopathy Checklist: Youth Version (PCL:YV) scores assigned by a licensed clinician to scores assigned by a graduate student across a sample of 82 juvenile offenders. Although both raters completed in-depth training and practice scoring cases, the graduate student had no prior clinical experience. The raters showed a high level of agreement in their scoring for 11 reliability check cases (intraclass correlation coefficient, ICCA,1 = .90 for PCL:YV Total score), but the scores assigned by the licensed clinician were better predictors of post-release recidivism (area under the curve, AUC = .77) than those assigned by the graduate student (AUC = .45). There was more variability in the scores assigned by the licensed clinician than those assigned by the graduate student, suggesting that more experienced clinicians' willingness to assign both high and low scores may help explain rater differences in predictive validity.

14.
Exp Mol Med ; 51(10): 1-13, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615975

RESUMO

The disruption of the retinal pigment epithelium (RPE), for example, through oxidative damage, is a common factor underlying age-related macular degeneration (AMD). Aberrant autophagy also contributes to AMD pathology, as autophagy maintains RPE homeostasis to ensure blood-retinal barrier (BRB) integrity and protect photoreceptors. Thioredoxin-interacting protein (TXNIP) promotes cellular oxidative stress by inhibiting thioredoxin reducing capacity and is in turn inversely regulated by reactive oxygen species levels; however, its role in oxidative stress-induced RPE cell dysfunction and the mechanistic link between TXNIP and autophagy are largely unknown. Here, we observed that TXNIP expression was rapidly downregulated in RPE cells under oxidative stress and that RPE cell proliferation was decreased. TXNIP knockdown demonstrated that the suppression of proliferation resulted from TXNIP depletion-induced autophagic flux, causing increased p53 activation via nuclear localization, which in turn enhanced AMPK phosphorylation and activation. Moreover, TXNIP downregulation further negatively impacted BRB integrity by disrupting RPE cell tight junctions and enhancing cell motility by phosphorylating, and thereby activating, Src kinase. Finally, we also revealed that TXNIP knockdown upregulated HIF-1α, leading to the enhanced secretion of VEGF from RPE cells and the stimulation of angiogenesis in cocultured human retinal microvascular endothelial cells. This suggests that the exposure of RPE cells to sustained oxidative stress may promote choroidal neovascularization, another AMD pathology. Together, these findings reveal three distinct mechanisms by which TXNIP downregulation disrupts RPE cell function and thereby exacerbates AMD pathogenesis. Accordingly, reinforcing or restoring BRB integrity by targeting TXNIP may serve as an effective therapeutic strategy for preventing or attenuating photoreceptor damage in AMD.


Assuntos
Barreira Hematorretiniana/metabolismo , Proteínas de Transporte/genética , Degeneração Macular/genética , Estresse Oxidativo/genética , Animais , Autofagia/genética , Barreira Hematorretiniana/patologia , Movimento Celular/genética , Regulação da Expressão Gênica/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Degeneração Macular/patologia , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Retina/metabolismo , Retina/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Tiorredoxinas/genética , Junções Íntimas/genética , Junções Íntimas/patologia , Proteína Supressora de Tumor p53/genética , Fator A de Crescimento do Endotélio Vascular/genética
15.
PLoS One ; 14(10): e0223404, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31661516

RESUMO

Discovering technology opportunities from the opinion of users can promote successful technological development by satisfying the needs of users. However, although previous approaches using opinion mining only have classified various needs of users into positive or negative categories, they cannot derive the main reasons for their opinion. To solve this problem, this research proposes an approach to exploring technology opportunity by structuring user needs with a concept of opinion trigger of objects and functions of the technology-based products. To discover technology opportunity, first, an opinion trigger is identified from review data using Naïve Base classifier and natural language processing. Second, the opinion triggers and patent keywords that have a similar meaning in context are clustered to discover the needs of the user and need-related technology. Then, the sentimental values of needs are calculated through graph-based semi-supervised learning. Finally, the needs of the user are classified in resolving the problem of vacant technology to discover technology opportunity. Then, an R&D strategy of each opportunity is suggested based on opinion triggers, patent keywords, and their property. Based on the concept of opinion trigger-based methodology, a case study is conducted on automobile-related reviews, extracting the customer needs and presenting important R&D projects such as an extracted need (cargo transportation) and its R&D strategy (resolving contradiction). The proposed approach can analyze the needs of user at a functional level to discover new technology opportunities.


Assuntos
Aprendizado de Máquina , Processamento de Linguagem Natural , Tecnologia , Algoritmos , Atitude , Humanos , Pesquisa
16.
J Microbiol ; 57(11): 982-990, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31659684

RESUMO

Microalgae and bacteria are known to be closely associated in diverse environments. To isolate dominant bacterial species associated with a green alga, Dunaliella tertiolecta, a photoreactor culture of the microalga was investigated using culture-based and culture-independent approaches. The bacterial community structure of the algal culture showed that the most abundant bacterial species under the culture conditions was related to the genus Winogradskyella. The closely related amplicon sequences, showing ≥ 99.5% 16S rRNA gene sequence similarity to one of the isolates, designated IMCC-33238T, constituted > 49% of the bacterial community and was therefore regarded as the most dominant species in the algal culture. Strain IMCC33238T was characterized by Gramstaining-negative and orange-colored rods. Phylogenetic analyses of the 16S rRNA genes as well as whole genome sequences revealed that strain IMCC33238T belonged to Winogradskyella and shared more than 97.2% 16S rRNA gene sequence similarity with Winogradskyella species. The strain contained iso-C15:1 G, iso-C15:0, iso-C15:0 3-OH, and summed feature 3 (C16:1ω6c and/or C16:1ω7c) as major fatty acids and MK-6 as the predominant quinone. The polar lipids found in strain IMCC33238T were phosphatidylethanolamine, two unidentified aminolipids, and three unidentified lipids. The genome of strain IMCC33238T was 3.37 Mbp in size with 33.9 mol% G + C content and proteorhodopsin. Many genes encoding folate and vitamin production are considered to play an important role in the bacteria-algae interaction. On the basis of phylogenetic and phenotypic characteristics, strain IMCC33238T represents a novel species in the genus Winogradskyella, for which the name Winogradskyella algicola sp. nov. is proposed. The type strain is IMCC33238T (= KACC 21192T = NBRC 113704T).


Assuntos
Clorofíceas/microbiologia , Flavobacteriaceae/classificação , Flavobacteriaceae/genética , Flavobacteriaceae/isolamento & purificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Benzoquinonas/química , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/fisiologia , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , República da Coreia , Rodopsinas Microbianas/química , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química , Sequenciamento Completo do Genoma
17.
Int J Syst Evol Microbiol ; 69(9): 2651-2657, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31157611

RESUMO

A Gram-stain-negative, obligately aerobic, cream-coloured, non-gliding, motile with a single polar flagellum and rod-shaped bacterium, designated IMCC34151T, was isolated from tidal flat sediment of the Yellow Sea, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain IMCC34151T belonged to the genus Pelagibacterium of the family Hyphomicrobiaceae and shared 94.7-96.8 % sequence similarities to Pelagibacterium species. Whole-genome sequencing of strain IMCC34151T revealed a genome size of 3.2 Mbp and a DNA G+C content of 62.6 mol%. The strain contained summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c), C19 : 0cyclo ω8c and C16 : 0 as the major fatty acids and ubiquinone-10 (Q-10) as the major respiratory quinone. The polar lipids detected in the strain were phosphatidylglycerol, diphosphatidylglycerol, two unidentified glycolipids and 12 unidentified lipids. On the basis of its phylogenetic and phenotypic characteristics, strain IMCC34151T is considered to represent a novel species of the genus Pelagibacterium, for which the name Pelagibacteriumsediminicola sp. nov. (type strain IMCC34151T =KACC 19595T=NBRC 113420T) is proposed.


Assuntos
Sedimentos Geológicos/microbiologia , Hyphomicrobiaceae/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hyphomicrobiaceae/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química
18.
J Microbiol ; 57(8): 661-667, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31012058

RESUMO

A Gram-stain-negative, rod-shaped, obligately aerobic, chemoheterotrophic bacterium which is motile by means of a single polar flagellum, designated SAORIC-263T, was isolated from deep seawater of the Pacific Ocean. Phylogenetic analyses based on 16S rRNA gene sequences and genomebased phylogeny revealed that strain SAORIC-263T belonged to the genus Sulfitobacter and shared 96.1-99.9% 16S rRNA gene sequence similarities with Sulfitobacter species. Wholegenome sequencing of strain SAORIC-263T revealed a genome size of 3.9Mbp and DNA G+C content of 61.3 mol%. The SAORIC-263T genome shared an average nucleotide identity and digital DNA-DNA hybridization of 79.1-88.5% and 18.9-35.0%, respectively, with other Sulfitobacter genomes. The SAORIC-263T genome contained the genes related to benzoate degradation, which are frequently found in deep-sea metagenome. The strain contained summed feature 8 (C18:1ω7c), C18:1ω7c 11-methyl, and C16:0 as the predominant cellular fatty acids as well as ubiquinone-10 (Q-10) as the major respiratory quinone. The major polar lipids of the strain were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, and aminolipid. On the basis of taxonomic data obtained in this study, it is suggested that strain SAORIC-263T represents a novel species of the genus Sulfitobacter, for which the name Sulfitobacter profundi sp. nov. is proposed. The type strain is SAORIC-263T (= KACC 21183T = NBRC 113428T).


Assuntos
Rhodobacteraceae/classificação , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana/métodos , Composição de Bases , DNA Bacteriano/genética , Oceano Pacífico , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/crescimento & desenvolvimento , Rhodobacteraceae/isolamento & purificação , Sequenciamento Completo do Genoma/métodos
19.
J Microbiol ; 57(5): 343-349, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30721459

RESUMO

A non-motile, yellow-pigmented bacterial strain, designated IMCC34762T, was isolated from a freshwater sample collected from Lake Cheongpyeong in Korea. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain IMCC-34762T formed a lineage within the genus Flavobacterium and was most closely related to F. pectinovorum DSM 6368T (98.3% sequence similarity), followed by F. piscis CCUG 60099T (98.3%), F. branchiicola 59B-3-09T (98.2%), and F. saccharophilum DSM 1811T (98.2%). The average nucleotide identity and the genome-to-genome distance between strain IMCC34762T and the closely related strains were 61-62% and 26-27%, respectively, indicating that IMCC34762T is a novel species of the genus Flavobacterium. The major fatty acids (> 5%) of strain IMCC34762T were summed feature 3 (C16:1ω6c and/or C16:1ω7c, 17.3%), iso-C15:0 (15.0%), iso-C15:0 G (9.0%), C15:0ω6c (7.4%), iso-C15:0 (7.4%), and iso-C16:0 (5.3%). The major respiratory quinone and polyamine were MK-6 and sym-homospermidine, respectively. The major polar lipids were phosphatidylethanolamine, an unidentified aminophospholipid, and an unidentified lipid. The DNA G + C content of strain IMCC34762T was 34.4 mol%. Based on the taxonomic data presented in this study, strain IMCC-34762T represents a novel species within the genus Flavobacterium, for which the name Flavobacterium aquariorum, sp. nov. is proposed. The type strain is IMCC34762T (= KACC 19725T = NBRC 113425T).


Assuntos
Flavobacterium/classificação , Flavobacterium/isolamento & purificação , Lagos/microbiologia , Rios/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Flavobacterium/genética , Genoma Bacteriano/genética , Fosfolipídeos/análise , Poliaminas/análise , Quinonas/análise , RNA Ribossômico 16S/genética , República da Coreia
20.
Nanotechnology ; 30(28): 285401, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-30645979

RESUMO

Films containing 8, 16, 24, 32 and 64 MoSe2 layers were synthesized using the modulated elemental reactants method. X-ray reflectivity patterns showed that the annealed films were the targeted number of MoSe2 layers thick with atomically smooth interfaces. In-plane x-ray diffraction (XRD) scans contained only hk0 reflections for crystalline MoSe2 monolayers. Specular XRD patterns contained only 00l reflections, also indicating that the hk0 plane of the MoSe2 layers are parallel to the substrate. Both XRD and electron microscopy techniques indicated that the hk0 planes are rotationally disordered with respect to one another, with all orientations equally probable for large areas. The rotational disorder between MoSe2 layers is present even when analyzed spots are within 10 nm of one another. Cross-plane thermal conductivities of 0.07-0.09 W m-1 K-1 were measured by time domain thermoreflectance, with the thinnest films exhibiting the lowest conductivity. The structural analysis suggests that the ultralow thermal conductivity is a consequence of rotational disorder, which increases the separation between MoSe2 layers. The bonding environment of the Se atoms also becomes significantly distorted from C 3v symmetry due to the rotational disorder between layers. This structural disorder efficiently reduces the group velocity of the transverse phonon modes but not that of longitudinal modes. Since rotational disorder between adjacent layers in heterostructures is expected if the constituents have incommensurate lattices, this study indicates that these heterostructures will have very low cross-plane thermal conductivity.

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