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1.
Front Nutr ; 11: 1331172, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38496794

RESUMO

Background: The effect of micronutrients on thyroid cancer has been studied in observational studies, however, the cause of relationships has not yet been determined. Thyroid cancer was the subject of a Mendelian randomization (MR) analysis of micronutrients. Aimed to determine whether micronutrient intake has a causal impact on the chance of developing thyroid cancer. Methods: We used a Mendelian randomization (MR) analysis with two samples. Our circulation levels of Cu, Ir, Zn, Ca, VD, and VC were reflected by genetic variations reported from GWAS in individuals of European ancestry. For the GWAS outcome of thyroid cancer. Sensitivity studies that included MR-Egger, weighted median/mode tests, and a more open selection of variations at a genome-wide sub-significant threshold were added to our inverse-variance weighted (IVW) MR study. Results: Using the IVW approach, we did not find evidence that any of the micronutrients to thyroid cancer (Cu: odds ratio [OR = 0.88, p = 0.41]; Zn: odds ratio [OR = 0.87, p = 0.40]; Ir: odds ratio [OR = 1.18, p = 0.39]; Ca: odds ratio [OR = 1.12, p = 0.43]; VC: odds ratio [OR = 0.95, p = 0.22]; VD: odds ratio [OR = 0.89, p = 0.04]). The heterogeneity (p > 0.05) and pleiotropy (p > 0.05) testing provided confirmatory evidence for the validity of our MR estimates. Conclusion: This study does not provide evidence that supplementation with micronutrients including Cu, Ir, Zn, Ca, VD, and VC can prevent thyroid cancer.

2.
Sci Total Environ ; 926: 172089, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38554966

RESUMO

Both alien plant invasions and soil microplastic pollution have become a concerning threat for terrestrial ecosystems, with consequences on the human well-being. However, our current knowledge of microplastic effects on the successful invasion of plants remains limited, despite numerous studies demonstrating the direct and indirect impacts of microplastics on plant performance. To address this knowledge gap, we conducted a greenhouse experiment involving the mixtures of soil and low-density polyethylene (LDPE) microplastic pellets and fragments at the concentrations of 0, 0.5 % and 2.0 %. Additionally, we included Solidago decurrens (native plant) and S. canadensis (alien invasive plant) as the target plants. Each pot contained an individual of either species, after six-month cultivation, plant biomass and antioxidant enzymes, as well as soil properties including soil moisture, pH, available nutrient, and microbial biomass were measured. Our results indicated that microplastic effects on soil properties and plant growth indices depended on the Solidago species, microplastic shapes and concentrations. For example, microplastics exerted positive effects on soil moisture of the soil with native species but negative effects with invasive species, which were impacted by microplastic shapes and concentrations, respectively. Microplastics significantly impacted catalase (P < 0.05) and superoxide dismutase (P < 0.01), aboveground biomass (P < 0.01), and belowground/aboveground biomass (P < 0.01) of the native species depending on microplastic shapes, but no significant effects on those of the invasive species. Furthermore, microplastics effects on soil properties, nutrient, nutrient ratio, and plant antioxidant enzyme activities contributed to plant biomass differently among these two species. These results suggested that the microplastics exerted a more pronounced impact on native Solidago plants than the invasive ones. This implies that the alien invasive species displays greater resistance to microplastic pollution, potentially promoting their invasion. Overall, our study contributes to a better understanding of the promoting effects of microplastic pollution on plant invasion.


Assuntos
Solo , Solidago , Humanos , Solo/química , Ecossistema , Espécies Introduzidas , Microplásticos , Plásticos/toxicidade , Antioxidantes , Plantas
3.
Discov Nano ; 18(1): 128, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845558

RESUMO

Silicon carbide (SiC) PiN diode has shown substantial promise as the freewheel diode for switch protection in a pulsed system. In this paper, we investigate the carrier lifetime (τ) modulation on pulsed current capability of SiC PiN diodes. The carrier lifetime in 4H-SiC is modulated by the generation of the Z1/2 center through neutron irradiation. Surprisingly, we found that the pulsed current of SiC PiN diodes shows a limited improvement when the carrier lifetime (τ) increases from 0.22 to 1.3 µs, while is significantly promoted as the carrier lifetime increases from 0.03 to 0.22 µs. This changing trend is obviously different from the on-state resistance, which decreases with the increased carrier lifetime. The simulation result indicates that the heat generation (i.e., maximum temperature rise) inside the PiN diodes, especially in the drift layer, is remarkably aggravated in the pulse tests for τ < 0.1 µs, but which is significantly suppressed as carrier lifetime rises to 0.2 µs and above. Therefore, the dependence of pulsed current on carrier lifetime is ascribed to the heat generation resulting from the carrier lifetime controlled conductivity modulation effect, which hence affects the temperature rise and brings about the failure of SiC PiN diodes under high pulsed current.

4.
NPJ Regen Med ; 8(1): 20, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024481

RESUMO

When the proliferation of residual hepatocytes is prohibited, biliary epithelial cells (BECs) transdifferentiate into nascent hepatocytes to accomplish liver regeneration. Despite significant interest in transdifferentiation, little is known about the maintenance of nascent hepatocytes in post-injured environments. Here, we perform an N-ethyl-N-nitrosourea (ENU) forward genetic screen and identify a mutant containing a nonsense mutation in the gene nibrin (nbn), which encodes a component of the Mre11-Rad50-Nbn (MRN) complex that activates DNA damage response (DDR). The regenerated hepatocytes cannot be maintained and exhibit apoptosis in the mutant. Mechanistically, the nbn mutation results in the abrogation of ATR-Chk1 signaling and accumulations of DNA damage in nascent hepatocytes, which eventually induces p53-mediated apoptosis. Furthermore, loss of rad50 or mre11a shows similar phenotypes. This study reveals that the activation of DDR by the MRN complex is essential for the survival of BEC-derived hepatocytes, addressing how to maintain nascent hepatocytes in the post-injured environments.

5.
Angew Chem Int Ed Engl ; 61(35): e202206311, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35789522

RESUMO

Imide-functionalized arenes have been one of the most promising acceptor (A) units in organic solar cells (OSCs). However, dithienophthalimide (DPI), a hybrid of thieno-[3,4-c]pyrrole-4,6-dione (TPD) and bithiophene imide (BTI) units, has not been revisited since its first synthesis, likely owing to the high synthetic cost of the reported method. In this work, we simplified the synthetic procedure of the DPI skeleton with a significant reduction of the synthetic cost by using chromium-mediated cyclization as the key chemistry. Using this method, two DPI-based nonhalogenated D-A copolymers are synthesized. The binary OSCs based on pBDTT-DPI-Me : Y6 achieves a power conversion efficiency as high as 16.55 %, highlighting DPI as an attractive A-unit for further exploration in OSCs.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35559719

RESUMO

A novel obligate anaerobic organism, designated DONG20-135T, was isolated from human faeces collected in Beijing, PR China. Cells were Gram-stain-negative, rod-shaped, non-motile and non-spore-forming. Growth occurred at 25‒45 °C (optimum, 30‒35 °C), a pH range of 6-9 (optimum, pH 8) and in the presence of 0‒3.5 % (w/v) NaCl (optimum, 0.5‒1.5 %). The major fatty acids were C16 : 0, C18 : 1 ω9c and C10 : 0, the polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, four glycolipids, six aminolipids, three aminophospholipids and four unidentified lipids. No respiratory quinones were detected. The cell-wall peptidoglycan of the strain was A1γ type, containing meso-diaminopimelic acid. The 16S rRNA gene sequences shared a lower identity (<92.7 % similarity) with the described species. The phylogenetic tree based on 16S rRNA gene sequences and the protein-concatamer tree showed that strain DONG20-135T formed a distinct lineage within the family Erysipelotrichaceae. The genomic DNA G + C content was 42.2 mol%. Based on the results of phenotypic, chemotaxonomic and genomic analyses, strain DONG20-135T represents a novel genus of the family Erysipelotrichaceae, for which the name Copranaerobaculum intestinale gen. nov., sp. nov. is proposed (=KCTC 15868T=CGMCC 1.17357T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Anaerobiose , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes , Humanos , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Chem Sci ; 12(42): 14224-14229, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34760208

RESUMO

Silicon-based cross-coupling has been recognized as one of the most reliable alternatives for constructing carbon-carbon bonds. However, the employment of such reaction as an efficient ring expansion strategy for silacycle synthesis is comparatively little known. Herein, we develop the first intermolecular silacyclization strategy involving Pd-catalyzed silicon-based C(sp2)-C(sp3) cross-coupling. This method allows the modular assembly of a vast array of structurally novel and interesting sila-benzo[b]oxepines with good functional group tolerance. The key to success for this reaction is that silicon atoms have a stronger affinity for oxygen nucleophiles than carbon nucleophiles, and silacyclobutanes (SCBs) have inherent ring-strain-release Lewis acidity.

8.
Nanoscale Res Lett ; 16(1): 141, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508306

RESUMO

In this paper, the effect of ultraviolet (UV) irradiation on the static characteristics of high voltage 4H-SiC PiN is investigated. No significant change is observed in the forward on state characteristic of 4H-SiC PiN diodes before and after ultraviolet light irradiation. However, it is found that the blocking voltage is significantly increased with UV irradiation, which is resulted from the depletion region width extension with the collection of positive charges under the increase of the surface negative charge density. The deep level transient spectroscopy reveals that the UV irradiation induced deep-level defects play a dominant role over the trapped negative charges, and therefore leads to the increase of blocking voltage of 4H-SiC PiN Diodes.

9.
Cancer Cell Int ; 21(1): 264, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001137

RESUMO

BACKGROUNDS: Gastric cancer (GC) is general disease in human digestive system with malignancy. Emerging findings indicated that hsa_circ_0031452 (circHECTD1) was strictly associated with carcinogenesis. Nevertheless, the role of circHECTD1 in drug-resistance still needed to be explained. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to examine the expression profiles of circHECTD1, microRNA (miR)-137, and pre-leukemia transcription factor 3 (PBX3). The function of circHECTD1 in tumorigenesis was evaluated via xenograft tumor model. The IC50 of Diosbulbin-B (DB) was detected using Cell Counting Kit-8 (CCK8). Cell-cycle and apoptosis were reckoned by flow cytometry. Besides, western blot was administrated to reckon the levels of PBX3 and cell apoptotic indicators. Moreover, the interrelation between miR-137 and circHECTD1 or PBX3 was expounded by dual-luciferase reporter, RNA immunoprecipitation (RIP) and RNA pull down assays. RESULTS: We uncovered that circHECTD1 was ectopically up-regulated in GC tissues and cells. CircHECTD1 deficiency sensitized DB-treatment in DB-evoked AGS and HGC-27 cells. In vivo assay, circHECTD1 silencing led to the tumor reduction. Also, circHECTD1 served as miR-137 sponge in a sequence-complementary manner. Furthermore, transfection of miR-137 inhibitor markedly eliminated circHECTD1 absence-mediated promotion of DB-sensitivity in GC cells. Moreover, PBX3, a target of miR-137, play a DB-resistant role in GC cells. Fascinatingly, the deletion of PBX3 reversed the impact of miR-137 repression and circHECTD1 knockdown on DB-sensitivity in vitro. CONCLUSIONS: CircHECTD1 served as an oncogene by a novel miR-137/PBX3 axis, which might supply an underlying biomarker for the diagnosis and prognosis of GC management.

10.
Antonie Van Leeuwenhoek ; 114(7): 1079-1089, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33895906

RESUMO

Six aerobic Gram-negative bacteria were isolated from seawater in Guangdong Province, P.R. China. Cells were observed to be Gram-negative, aerobic, non-motile and non-spore forming. Growth of the designated type strain 19X3-30T occurred at a temperature range of 14-37 °C (optimum, 28 °C), a pH range of 6.0-8.0 (optimum, pH 7) and up to 7.5% NaCl (optimum, 1.5%; w/v), and was enhanced by CO2 and L-cysteine supplementation. The major polar lipids identified in strain 19X3-30T were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The principal cellular fatty acids profile showed the presence of anteiso-C15:0, anteiso-C17:0 and C18:0 (> 8% of total fatty acids), and the respiratory quinone was ubiquinone 8 (UQ-8). According to the analysis of 16S rRNA gene sequences, these strains represented a novel species within the family Fastidiosibacteraceae, sharing maximum similarities with Cysteiniphilum litorale DSM 101832T (96.6%) and Cysteiniphilum halobium DSM 103992T (95.3%). Phylogenetic dendrograms based on 16S rRNA gene and protein marker genes from the genomic sequences both indicated that the strains formed a monophyletic lineage closely linked to the genus Cysteiniphilum, which was also supported by the UPGMA dendrogram based on the MALDI-TOF MS profile. The genomic DNA G + C contents of six strains ranged from 38.0% to 38.1%. Based on different taxonomic genomic metrics, phylogeny and phenotypic features, we propose that the strains warrant the assignment to a novel species, for which the name Cysteiniphilum marinum sp. nov. is proposed. The type strain is 19X3-30T (= KCTC 82154T = CGMCC 1.18585T).


Assuntos
Fosfolipídeos , Água do Mar , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos , Gammaproteobacteria , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
J Am Chem Soc ; 143(15): 5903-5916, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33825485

RESUMO

Although polycyclic aromatic hydrocarbons (PAHs) with a nitrogen-boron-nitrogen (NBN) moiety have recently attracted tremendous interest due to their intriguing electronic and optoelectronic properties, all of the NBN-fused π-systems reported to date are called NBN-dibenzophenalenes and were synthesized by electrophilic aromatic substitution. The synthesis of NBN-phenalenes remains challenging, and transition-metal catalysis has never been utilized to construct NBN-embedded π-scaffolds. Herein, a palladium-catalyzed cyclization/bicyclization strategy was developed for the synthesis of diverse pentagonal and hexagonal ring-fused NBN-phenalenes and half-NBN-phenalenes. All of the NBN-embedded π-scaffolds presented in our paper are fluorescent in both solution and the solid state. Further investigations showed that the five-membered NBN rings exhibit the properties of traditional luminogens, while those with a six-membered NBN ring generally undergo photoinduced structural planarization (PISP) and exhibit different colors and quantum yields of fluorescence with different concentrations in solution. Time-resolved spectroscopy and TD-DFT calculations revealed that excited-state aromatization is the driving force for PISP in hexagonal ring-fused NBN-π systems, leading to the formation of excimers. Notably, the scope of PISP compounds is still quite limited, and PISP has never been observed in NBN-π systems before. These hexagonal ring-fused NBN-π systems constitute a novel PISP molecular library and appear to be a new class of aggregation-induced excimer emission (AIEE) materials. Finally, the AIEE behavior of these six-membered NBN rings was applied to the detection of nitro explosives, achieving excellent sensitivity. In general, this work provides a new viewpoint for synthesizing NBN-fused π-systems and understanding the excited-state motion of luminogens.

12.
Asia Pac J Clin Nutr ; 30(1): 87-98, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787044

RESUMO

BACKGROUND AND OBJECTIVES: PUFAs play critical roles in the development of nonalcoholic fatty liver disease (NAFLD). This study examined the associations between dietary n-3 and n-6 PUFA intake and NAFLD risk in a US population. METHODS AND STUDY DESIGN: Data from the National Health and Nutrition Examination Survey (NHANES) 2007-2014 was used in this cross-sectional study. Data on dietary n-3 and n-6 PUFAs were extracted through two 24-h dietary recall interviews, and the dietary n-3 and n-6 PUFA intakes were adjusted by weight. NAFLD was defined based on the US fatty liver index (FLI) value ≥30. Multivariable logistic regression models and restricted cubic spline models were applied to investigate the associations between dietary n-3 and n-6 PUFA intakes and NAFLD risk. RESULTS: Dietary n-3 and n-6 PUFA intakes were inversely associated with NAFLD risk. The multivariable-adjusted OR (95% CI) of NAFLD for the highest versus lowest quartile of dietary n-3 and n-6 PUFA intakes was 0.24 (0.17-0.35) and 0.18 (0.13-0.26), respectively. In stratified analyses by sex and age, the negative associations between dietary n-3 and n-6 PUFA intakes and NAFLD risk were significant in men, women, and individuals younger and older than 45 years. Dose-response analyses indicated that NAFLD risk was associated with dietary n-3 and n-6 PUFA intakes in a nonlinear manner. CONCLUSIONS: Dietary n-3 and n-6 PUFA intakes were inversely associated with NAFLD risk in US adults.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Pré-Escolar , Estudos Transversais , Dieta , Ácidos Graxos Ômega-6 , Feminino , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Inquéritos Nutricionais , Estados Unidos/epidemiologia
14.
Elife ; 102021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33587032

RESUMO

Communications between actin filaments and integrin-mediated focal adhesion (FA) are crucial for cell adhesion and migration. As a core platform to organize FA proteins, the tripartite ILK/PINCH/Parvin (IPP) complex interacts with actin filaments to regulate the cytoskeleton-FA crosstalk. Rsu1, a Ras suppressor, is enriched in FA through PINCH1 and plays important roles in regulating F-actin structures. Here, we solved crystal structures of the Rsu1/PINCH1 complex, in which the leucine-rich-repeats of Rsu1 form a solenoid structure to tightly associate with the C-terminal region of PINCH1. Further structural analysis uncovered that the interaction between Rsu1 and PINCH1 blocks the IPP-mediated F-actin bundling by disrupting the binding of PINCH1 to actin. Consistently, overexpressing Rsu1 in HeLa cells impairs stress fiber formation and cell spreading. Together, our findings demonstrated that Rsu1 is critical for tuning the communication between F-actin and FA by interacting with the IPP complex and negatively modulating the F-actin bundling.


Assuntos
Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas com Domínio LIM/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição/metabolismo , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Actinas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Adesões Focais/genética , Adesões Focais/metabolismo , Células HeLa , Humanos , Proteínas com Domínio LIM/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas dos Microfilamentos/genética , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Fatores de Transcrição/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-33284100

RESUMO

Four strains (km711T, km714, km542 and km524), representing a novel Legionella species, were isolated from aquatic environments in northern PR China. Cells were Gram-stain-negative, rod-shaped, microaerobic, motile and growth depended on l-cysteine. They grew at 25‒42 °C (optimum, 35‒37 °C) and could tolerate up to 1.5 % (w/v) NaCl (optimum, 0.5 %). The major fatty acids (>5 %) of the type strain km711T were C17 : 0 anteiso, C15 : 0 anteiso, iso-C16 : 0 and C16 : 1 ω7c and/or iso-C15 : 0 2OH. The pairwise comparison values were <96.1 % for 16S rRNA gene sequences, 23.3‒28.7 % interspecies variation for mip gene sequences, <93.6 % average nucleotide identity and <72.8 % average amino acid identity between these four strains and related type strains within the genus Legionella. The phylogenetic tree based on the four concatenated genes (16S rRNA, mip, rpoB and rnpB) and protein-concatamer tree based on concatenation of 21 protein markers both revealed that these four strains formed a separate phylogenetic branch cluster within the genus Legionella. The results of phenotypic and genotypic features suggest that these four strains represent a novel species of the genus Legionella, for which the name Legionella septentrionalis sp. nov. is proposed (type strain km711T=KCTC 15655T=NBRC 113219T).


Assuntos
Legionella/classificação , Filogenia , Microbiologia da Água , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Legionella/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
16.
Int J Syst Evol Microbiol ; 70(5): 3264-3272, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375983

RESUMO

Four strains (SYSU SYW-1T, SYW-2, SYW-3 and XLW-1) were isolated from seawater near the shore in Guangdong Province, China. Cells were Gram-stain-negative, aerobic, non-motile and non-spore-forming. Growth was observed at a temperature range of 16-40 °C (optimum, 32 °C), a pH range of 4-8 (optimum, pH 7) and in the presence of up to 10 % (w/v) NaCl. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and an unidentified phospholipid. The respiratory quinone was ubiquinone 8 (UQ-8), and the predominant fatty acids were C18 : 0 3-OH, C10 : 0, C14 : 0 and C18 : 1ω9c. Comparison of 16S rRNA gene and genome sequences confirmed that these strains represented a novel member of the genus Francisella, with less than 98.8 % 16S rRNA gene sequence similarity and less than 95 % genomic average nucleotide identity to recognized Francisella species. The phylogenetic tree based on 16S rRNA gene sequences and the protein-concatamer tree based on a concatenation of 28 protein marker sequences both indicated that the strains clustered with 'Francisella salina' TX07-7308 and 'Francisella marina' E95-16, but formed a distinct lineage group among the other members of the genus Francisella. The DNA G+C contents of the four strains were determined to be 32.9, 32.7, 32.9 and 32.9 %, respectively (genome). On the basis of phenotypic and genotypic features, the strains are considered to represent a novel species of the genus Francisella, for which the name Francisella salimarina sp. nov. is proposed. The type strain is SYSU SYW-1T (=CGMCC 1.17031T=NBRC 113781T).


Assuntos
Francisella/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Francisella/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
17.
Int J Syst Evol Microbiol ; 70(4): 2588-2595, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32163029

RESUMO

Two Haemophilus-like isolates with similar biochemical characteristics, designated strains SZY H1T and SZY H2, were isolated from human semen specimens. Cells were Gram-negative, non-motile, non-acid-fast, pleomorphic rods or coccobacilli. The major fatty acids (>10 %) were C16 : 0, C14 : 0, iso-C16 : 0 and/or C14 : 0 3-OH and C16 : 1 ω6c and/or C16 : 1 ω7c. The polar lipids were determined to be phosphatidylethanolamine, phosphatidylglycerol, an unidentified phospholipid, an unidentified aminophospholipid, two unidentified polar lipids and four unidentified aminolipids. The major polyamine was found to be cadaverine. The near-full-length (1462 nt) 16S rRNA gene sequences analysis showed the two isolates were nearly identical (>99.8 %), and closely matched Haemophilus haemolyticus ATCC 33390T with 98.9-99.1 % sequence similarities. Phylogenetic analysis based on 16S rRNA gene sequences and concatenation of 30 protein markers also revealed that the isolates clustered together with H. haemolyticus ATCC 33390T, and formed a distinct lineage well separated from the other members of the genus Haemophilus. Further, the average nucleotide identity values between the two isolates and their related species were below the established cut-off values for species delineation (95 %). Based on these findings, the two isolates are considered to represent a new species of the genus Haemophilus, for which name Haemophilus seminalis sp. nov. is proposed. The type strain is SZY H1T (=NBRC 113782T=CGMCC 1.17137T).


Assuntos
Haemophilus/classificação , Filogenia , Sêmen/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , Cadaverina/química , China , DNA Bacteriano/genética , Ácidos Graxos/química , Haemophilus/isolamento & purificação , Humanos , Masculino , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
18.
Int J Syst Evol Microbiol ; 70(1): 624-630, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31697226

RESUMO

A novel Vogesella strain, YM-1T, was recovered from human urine in PR China in 2017. Cells of strain YM-1T were Gram-stain-negative, rod-shaped, aerobic, motile, non-spore-forming and poly-ß-hydroxybutyrate-accumulating. The strain contained C16:1ω6c/C 16:1ω7c, C16:0 and C18:0ω7c as major fatty acids; phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unidentified phospholipid as major polar lipids; and ubiquinone-8 as the predominant respiratory quinone. Comparison of 16S rRNA gene sequences indicated that this strain had highest similarities to Vogesella perlucida DS-28T (98.8 %) and Vogesella mureinivorans 389T (98.1 %). The results of phylogenetic analysis based on the 16S rRNA gene sequences revealed that the novel strain was clustered and well separated with V. perlucida DS-28T and V. mureinivorans 389T within the genus Vogesella. The average nucleotide identity (ANI) and amino acid identity (AAI) analyses showed that this strain was not identified as V. perlucida DS-28T or V. mureinivorans 389T, with values well below the threshold limit for species demarcation (ANI <88.1 %, AAI <88.6 %). Based on the above results, strain YM-1T is proposed to be a novel species of the genus Vogesella with the name Vogesella urethralis sp. nov. (YM-1T=NBRC 113779=CGMCC 1.17135).


Assuntos
Betaproteobacteria/classificação , Filogenia , Urina/microbiologia , Bactérias Aeróbias/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Betaproteobacteria/isolamento & purificação , China , DNA Bacteriano/genética , Ácidos Graxos/química , Humanos , Hidroxibutiratos/metabolismo , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Poliésteres/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
19.
Materials (Basel) ; 12(24)2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817311

RESUMO

An abnormal star-like defect was found on the failed SiC gate turn-off thyristor (GTO) devices after metal removal and KOH etching at 450 °C in this work. It is of extraordinary larger size of 210-580 µm, even much larger than the etch pit of a micropipe in 4H-SiC. In addition, the abnormal star-like defect, exhibiting the consistent orientation with the six-fold symmetry of silicon carbide, was found to consist of several penetrating dislocations with the help of a LEXT OLS4000 3D laser confocal microscope. These abnormal star-like etch pits can severely reduce the forward blocking characteristic of GTOs, while exerting insignificant influence on the forward current-voltage characteristics between anode and gate electrode of the 4H-SiC GTO devices. Interestingly, the relationship between forward voltage drop and dislocation density is affected by the abnormal star-like defect. A regular increase of forward voltage drop at 100 A/cm2 was observed with the increasing dislocation density, while this correlation disappears in the presence of an abnormal star-like defect.

20.
Antonie Van Leeuwenhoek ; 112(6): 877-886, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30603801

RESUMO

A Gram-negative, aerobic, non-motile and non-spore forming bacterium, designated strain SYSU WZ-2T, was isolated from an estuarine seawater sample. Growth of strain SYSU WZ-2T was observed at temperature range of 10-40° C (optimum, 32 °C), pH range of 6-10 (optimum, pH 7-8) and in the presence of up to 5.0% NaCl (w/v). The DNA G+C content of the novel strain was determined to be 30.1% (genome). The major polar lipids were found to be diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, an unidentified aminolipid, two unidentified aminophospholipids and two unidentified phospholipids. The major fatty acids were C18:0 3-OH (27.5%), C18:1ω9c (19.3%), C16:0 (17.0%) and C14:0 (12.9%). The respiratory quinone was found to be ubiquinone Q8. Pairwise comparison of the 16S rRNA gene sequence showed that strain SYSU WZ-2T shares high identities with members of the genera Francisella (94.8-95.9%) and Allofrancisella (93.8-94.2%). The phylogenetic dendrograms based on 16S rRNA gene sequences with the members of the family Francisellaceae showed that the strain SYSU WZ-2T formed a distinct phylogenetic lineage well separated from the members of the genera Francisella and Allofrancisella. MALDI-TOF mass spectrometric analysis also depicted a different profile for strain SYSU WZ-2T compared with those of members of the genera Francisella and Allofrancisella. Based on the above results and differences in phenotypic and chemotaxonomic features, strain SYSU WZ-2T is characterized to represent a new species of a novel genus, for which the name Pseudofrancisella aestuarii gen. nov., sp. nov. is proposed (type strain SYSU WZ-2T = KCTC 52557T = CGMCC 1.13718T).


Assuntos
Francisella/isolamento & purificação , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Francisella/classificação , Francisella/genética , Francisella/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/análise
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