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1.
Inorg Chem ; 63(19): 8750-8763, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38693869

RESUMEN

Using a quinoline substituted Qsal ligand, Hqsal-5-Brq (Hqsal-5-Brq = N-(5-bromo-8-quinolyl)salicylaldimine), four FeIII complexes, [Fe(qsal-5-Brq)2]A·CH3OH (Y = NO3- (1NO3), BF4- (2BF4), PF6- (3PF6), OTf- (4OTf), were prepared and characterized. Structure analysis revealed that complex 2BF4 contained two species (2BF4(P1̅) and 2BF4(C2/c)). In these compounds except 3PF6, the [Fe(qsal-5-Brq)2]+ cations form 1D chains through π-π interactions and other weak interactions. Adjacent chains are connected to form the 2D "Chain Layer" structures and 3D structures through various supramolecular interactions. For 3PF6, a "Dimer Chain" structure is formed from the loosely connected dimers. Magnetic studies revealed that compounds 1NO3 and 2BF4(P1̅) displayed abrupt hysteretic SCO with the transition temperature T1/2↓ = 235 K, T1/2↑ = 240 K for 1NO3 and T1/2↓ = 230 K, T1/2↑ = 235 K for 2BF4(P1̅), while compounds 3PF6 and 4OTf are in the HS state. Desolvation of the complexes significantly modifies their SCO properties: the desolvated 1NO3 and 2BF4 show a gradual SCO, desolvated 3PF6 undergoes a two-step SCO, and desolvated 4OTf exhibits a hysteretic transition. Overall, this work reported the FeIII-SCO complexes of the quinoline-substituted Hqsal ligand and highlighted the potential of these ligands for the development of interesting FeIII-SCO materials.

2.
Biomed Eng Online ; 23(1): 10, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38279147

RESUMEN

BACKGROUND: Functional electrical stimulation (FES) can be used in rehabilitation to aid or improve function in people with paralysis. In clinical settings, it is common practice to use transcutaneous electrodes to apply the electrical stimulation, since they are non-invasive, and can be easily applied and repositioned as necessary. However, the current electrode options available for transcutaneous FES are limited and can have practical disadvantages, such as the need for a wet interface with the skin for better comfort and performance. Hence, we were motivated to develop a dry stimulation electrode which could perform equivalently or better than existing commercially available options. METHODS: We manufactured a thin-film dry polymer nanocomposite electrode, characterized it, and tested its performance for stimulation purposes with thirteen healthy individuals. We compared its functionality in terms of stimulation-induced muscle torque and comfort level against two other types of transcutaneous electrodes: self-adhesive hydrogel and carbon rubber. Each electrode type was also tested using three different stimulators and different intensity levels of stimulation. RESULTS: We found the proposed dry polymer nanocomposite electrode to be functional for stimulation, as there was no statistically significant difference between its performance to the other standard electrodes. Namely, the proposed dry electrode had comparable muscle torque generated and comfort level as the self-adhesive hydrogel and carbon rubber electrodes. From all combinations of electrode type and stimulators tested, the dry polymer nanocomposite electrode with the MyndSearch stimulator had the most comfortable average rating. CONCLUSIONS: The dry polymer nanocomposite electrode is a durable and flexible alternative to existing self-adhesive hydrogel and carbon rubber electrodes, which can be used without the addition of a wet interfacing agent (i.e., water or gel) to perform as well as the current electrodes used for stimulation purposes.


Asunto(s)
Cementos de Resina , Goma , Humanos , Estimulación Eléctrica , Hidrogeles , Electrodos , Carbono
3.
Angew Chem Int Ed Engl ; 63(25): e202405791, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38593214

RESUMEN

Herein, we present catalyst-regulated switchable site-selective hydrosilylation of enynes, which are suitable for a wide range of alkyl and aryl substituted polar enynes and exhibit excellent functional group compatibility. Under the optimized conditions, silyl groups can be precisely installed at various positions of 1,3-dienes. While α- and γ-silylation products were obtained under platinum-catalytic systems, ß-silylation products were delivered with [Cp*RuCl]4 as catalyst. This process lead to the formation of 1,3-dienoates with diverse substitutions, which would pose challenges with other methodologies.

4.
Anal Chem ; 95(21): 8325-8331, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37191948

RESUMEN

Probing the single-cell mechanobiology in situ is imperative for microbial processes in the medical, industrial, and agricultural realms, but it remains a challenge. Herein, we present a single-cell force microscopy method that can be used to measure microbial adhesion strength under anaerobic conditions in situ. This method integrates atomic force microscopy with an anaerobic liquid cell and inverted fluorescence microscopy. We obtained the nanomechanical measurements of the single anaerobic bacterium Ethanoligenens harbinense YUAN-3 and the methanogenic archaeon Methanosarcina acetivorans C2A and their nanoscale adhesion forces in the presence of sulfoxaflor, a successor of neonicotinoid pesticides. This study presents a new tool for in situ single-cell force measurements of various anoxic and anaerobic species and provides new perspectives for evaluating the potential environmental risk of neonicotinoid applications in ecosystems.


Asunto(s)
Ecosistema , Anaerobiosis , Composición de Base , Análisis de Secuencia de ADN , Filogenia , ARN Ribosómico 16S , Microscopía de Fuerza Atómica/métodos
5.
Inorg Chem ; 62(37): 14863-14872, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37676750

RESUMEN

Cooperative spin crossover transitions with thermal hysteresis loops are rarely observed in cobalt(II) complexes. Herein, two new mononuclear cobalt(II) complexes with hysteretic spin crossover at relatively high temperatures (from 320 to 400 K), namely, [Co(terpy-CH2OH)2]·X2 (terpy-CH2OH = 4'-(hydroxymethyl)-2,2';6',2″-terpyridine, X = SCN-(1) and SeCN- (2)), have been synthesized and characterized structurally and magnetically. Both compounds are mononuclear CoII complexes with two chelating terpy-CH2OH ligands. Magnetic measurements revealed the existence of the hysteretic SCO transitions for both complexes. For compound 1, a one-step transition with T1/2↑= 334.5 K was observed upon heating, while a two-step transition is observed upon cooling with T1/2↓(1) = 329.3 K and T1/2↓(2) = 324.1 K (at a temperature sweep rate of 5 K/min). As for compound 2, a hysteresis loop with a width of 5 K (T1/2↓ = 391.6 K and T1/2↑ = 396.6 K, at a sweep rate of 5 K/min) can be observed. Thanks to the absence of the crystallized lattice solvents, their single crystals are stable enough at high temperatures for the structure determination at both spin states, which reveals that the hysteretic SCO transitions in both complexes originate from the crystallographic phase transitions involving a thermally induced order-disorder transition of the dangling -CH2OH groups in the ligand. This work shows that the modification of the terpy ligand has an important effect on the magnetic properties of the resulting cobalt(II) complexes.

6.
Plant Dis ; 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37337446

RESUMEN

Melon (Cucumis melo L.) is a member of the Cucurbitaceae family, and is an important economic and horticultural crop. In March 2022, melon plants in greenhouses exhibited severe leaf yellow spot symptoms in Changjiang County (109°13'N, 19°28'E), Hainan Province. The incidence of the disease was about 30-50%. Lesions initially appeared as yellow dots on leaves and expanded irregularly. Gradually, brown spots appeared, and finally the whole leaves turned yellow and resulted in blighting and death of foliage (Figure 1.). A total of four symptomatic plants were sampled from about 0.2 ha of an area. Symptomatic leaves were excised, surface disinfected with 2% (w/v) NaOCl, rinsed three times with sterile distilled water, and placed on potato dextrose agar (PDA) followed by incubation at 25°C in the dark for 5 days. The pure cultures were obtained by the hyphal-tip method. A total of eight fungal isolates with similar colony characteristics were recovered from the four symptomatic plants. Three DNA fragments (ITS, TEF1, and RPB2) of the eight isolates showed 100% sequence identity based on the molecular identification methods described below. Therefore, one of the isolates, M2JP-3, was chosen for identification and test of the pathogenicity. The colony of M2JP-3 on PDA at 25°C for 5 days was white with yellow-brown pigmentation in the center (Figure 2A-B). From 10-day-old cultures grown on CLA (Fisher et al. 1982), macroconidia (n = 50) were falcate, slender, curved dorsiventrally, tapering towards both ends, 3 to 7 septate, and measured 24.5 to 52.1 x 3.7 to 4.7 µm. The microconidia (n = 50) were straight or slightly curved, septate 0 to 2, and measured 9.9 to 16.3 x 2.5 to 3.7 µm (Figure 2C-E). For molecular identification, genomic DNA was extracted using the method previously described (Khan et al. 2021),the internal transcribed spacer (ITS), translation elongation factor 1α (TEF1) and DNA-dependent RNA polymerase subunit II (RPB2) were amplified, respectively, using primers ITS1/ITS4 (White et al. 1990), EF1/ EF2 (O'Donnell et al. 1998), and 5F2/7cR (Reeb et al. 2004). The 529 bp (ITS), 723 bp (TEF1), and 965bp (RPB2) sequences were deposited in GenBank with acce. nos. OP303211, OP312675 and OP312674, respectively. A phylogenetic tree was constructed using the concatenated three gene sequences of M2JP-3 and that of the Fusarium incarnatum-equiseti species complex (FIESC) (Xia et al. 2019) based on Maximum Likelihood (Figure 3). M2JP-3 was grouped together with the F. pernambucanum strain NRRL 32864 (accession no. GQ505702 for ITS, GQ505613 for TEF1and GQ505791 for RPB2), and shared 100% concatenated sequence identity. For pathogenicity tests of M2JP-3, seeds of melon cultivar Jinmeiren were surface disinfected and sowed in soil in three replicated pots in a greenhouse at 26 °C under natural light. Healthy leaves of the melon plants were wounded with needles and inoculated with mycelial plugs of M2JP-3 or PDA plugs as control. . Symptoms similar to the original greenhouse symptoms were observed at 7 days after inoculation (Figure 4). The control leaves were asymptomatic. The same fungus was reisolated from the inoculated leaves, as identified based on morphology and molecular evidence, which confirmed the Kochs' postulates. To our knowledge, this is the first time Fusarium pernambucanum has been recorded causing leaf yellow spot disease on melon. Further, findings of the present study will help to develop effective disease management strategies against Fusarium pernambucanum Leaf Yellow Spot on melon in China.

7.
J Intell Mater Syst Struct ; 34(20): 2379-2392, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37970097

RESUMEN

Applying tessellated origami patterns to the design of mechanical materials can enhance properties such as strength-to-weight ratio and impact absorption ability. Another advantage is the predictability of the deformation mechanics since origami materials typically deform through the folding and unfolding of their creases. This work focuses on creating 4D printed flexible tubular origami based on three different origami patterns: the accordion, the Kresling and the Yoshimura origami patterns, fabricated with a flexible polylactic acid (PLA) filament with heat-activated shape memory effect. The shape memory characteristics of the self-unfolding structures were then harnessed at 60°C, 75°C and 90°C. Due to differences in the folding patterns of each origami design, significant differences in behaviour were observed during shape programming and actuation. Among the three patterns, the accordion proved to be the most effective for actuation as the overall structure can be compressed following the folding crease lines. In comparison, the Kresling pattern exhibited cracking at crease locations during deformation, while the Yoshimura pattern buckled and did not fold as expected at the crease lines. To demonstrate a potential application, an accordion-patterned origami 4D printed tube for use in hand rehabilitation devices was designed and tested as a proof-of-concept prototype incorporating self-unfolding origami.

8.
Inorg Chem ; 61(44): 17537-17549, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36288795

RESUMEN

Solvent effects on the structures and magnetic properties of single-molecule magnets (SMMs) have been of great interest for modification of the SMMs using chemical modulation. By systematically varying the reaction solvents (MeOH, ethanol, n-propanol, and n-butanol), we have successfully synthesized a series of DyIII-H4daps complexes (H4daps = N',N‴-[(1E,1'E)-pyridine-2,6-diylbis(ethan-1-yl-1-ylidene)]bis(2-hydroxybenzohydrazide), including two binuclear compounds, [Dy2(H2daps)2(MeOH)4(H2O)2](CF3SO3)2·0.5MeOH (1MeOH) and [Dy2(H2daps)3(EtOH)2]·2EtOH·Et2O (2EtOH), and two mononuclear compounds, [Dy(H4daps)2](CF3SO3)3·n-PrOH (3PrOH) and [Dy(H4daps)(CF3SO3)3(n-BuOH)]·0.5Et2O (4BuOH). Using different solvents, the ligand-to-metal ratios can be adjusted from 1:1 in 1MeOH and 4BuOH to 3:2 in 2EtOH and 2:1 in 3PrOH. Through the solvent crossover experiments, the role of the solvents and the conditions to form these complexes were carefully studied. The size of the different alcohols, their coordination ability to the DyIII center, and the solubility of the complexes in these alcohols might affect the assembly process and lead to modification of the structures and magnetic properties of these DyIII-H4daps complexes. Magnetic studies revealed that these four complexes all exhibit slow magnetic relaxation under a zero or an applied direct-current field, with an energy barrier of about 100 K for the binuclear compound 1MeOH. In combination with theoretical calculations, the magnetic-structure relationship of these four compounds has been analyzed. This work demonstrates the crucial role of different solvent molecules in the fine-tuning of the structures and magnetic performances of different lanthanide complexes.

9.
Inorg Chem ; 61(4): 2272-2283, 2022 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-35025491

RESUMEN

Chemical modulation on the structures and physical properties of the coordination complexes is of great interest for the preparation of new functional materials. By changing the acidity or basicity of the reaction medium, the deprotonation degree of a multidentate ligand with multiple active protons, H4daps (H4daps = N',N'″-((1E,1'E)-pyridine-2,6-diylbis(ethan-1-yl-1-ylidene))bis(2-hydroxybenzohydrazide)), can be regulated on purpose. With this ligand of different deprotonation and charges, three new DyIII complexes ([Dy(H3daps)(CH3COO)2(EtOH)]·CH3COOH (1Dy), [Dy2(H2daps)2(EtOH)2(H2O)2(MeOH)2](CF3SO3)2·(H2O)2 (2Dy), and [Dy3(H1daps)2(H2daps)(µ3-OH)(EtOH)(H2O)] (3Dy)) of different nuclearities (mono-, di-, and trinuclear for 1Dy to 3Dy, respectively) have been synthesized and characterized structurally and magnetically. Analyses on the related bond lengths and resulting hydrogen bond modes in the complexes provide the details of the deprotonation position and the charge of the ligands, which can be in the form of H3daps-, H2daps2-, and H1daps3-. Interestingly, the more deprotonated ligand can act as a bridging ligand between the DyIII centers using the phenol and/or carbonyl oxygen atoms, which leads to the multinuclear structures. Magnetic studies on these complexes revealed that complex 1Dy is a field-induced single-molecule magnet (SMM), while complexes 2Dy and 3Dy show SMM behavior under a zero dc field.

10.
Antonie Van Leeuwenhoek ; 115(3): 353-364, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35088183

RESUMEN

A bacterial strain, designated AETb3-4T was isolated from the rhizosphere of lily. Comparison of 16S rRNA gene sequences showed that the sequence from strain AETb3-4T exhibits high sequence similarity with those of Arthrobacter silviterrae KIS14-16T (97.9%), Arthrobacter livingstonensis LI2T (97.2%) and Arthrobacter stackebrandtii CCM 2783T (97.0%). Whole genome average nucleotide identity (ANI) and the digital DNA-DNA hybridization (dDDH) values between strain AETb3-4T and the reference strains A. silviterrae DSM 27180T, A. livingstonensis L12T and A. stackebrandtii DSM 16005T were below 83.6% and 27.7%, respectively, values which are considerably below the proposed thresholds for the species delineation, consistent with the proposal that strain AETb3-4T represents a novel species. The genome size of strain AETb3-4T is 4.33 Mb and the genomic DNA G + C content is 67.3%. The main polar lipids were identified as phosphatidylglycerol, diphosphatidylglycero, phosphatidylinositol and an unidentified glycolipid. The major fatty acids (> 10%) were identified as anteiso-C15: 0 and anteiso-C17: 0. The predominant menaquinone was found to be menaquinone 9 (MK-9) (H2) (82.2%). Phenotypic tests allowed the strain to be differentiated from its close phylogenetic neighbors. Based on the results obtained, it is proposed that the strain AETb3-4T (= CFCC 16390T = LMG 31708T) represents a novel species in the genus Arthrobacter, for which the names Arthrobacter wenxiniae sp. nov. is proposed. In addition, the novel strain AETb3-4T has multiple plant growth-promoting characters including ACC-deaminase activity and production of IAA. Furthermore, the genome contains secondary metabolite biosynthesis gene clusters, including a carotenoid biosynthetic gene cluster, suggesting potential capacities for secondary metabolite synthesis. These data suggest that strain AETb3-4T may have potential applications both in medicine and sustainable agriculture.


Asunto(s)
Arthrobacter , Técnicas de Tipificación Bacteriana , Carotenoides , ADN Bacteriano/genética , Ácidos Grasos , Familia de Multigenes , Hibridación de Ácido Nucleico , Peptidoglicano , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2
11.
Sensors (Basel) ; 23(1)2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36617030

RESUMEN

When we think of "soft" in terms of socially assistive robots (SARs), it is mainly in reference to the soft outer shells of these robots, ranging from robotic teddy bears to furry robot pets. However, soft robotics is a promising field that has not yet been leveraged by SAR design. Soft robotics is the incorporation of smart materials to achieve biomimetic motions, active deformations, and responsive sensing. By utilizing these distinctive characteristics, a new type of SAR can be developed that has the potential to be safer to interact with, more flexible, and uniquely uses novel interaction modes (colors/shapes) to engage in a heighted human-robot interaction. In this perspective article, we coin this new collaborative research area as SoftSAR. We provide extensive discussions on just how soft robotics can be utilized to positively impact SARs, from their actuation mechanisms to the sensory designs, and how valuable they will be in informing future SAR design and applications. With extensive discussions on the fundamental mechanisms of soft robotic technologies, we outline a number of key SAR research areas that can benefit from using unique soft robotic mechanisms, which will result in the creation of the new field of SoftSAR.


Asunto(s)
Robótica , Materiales Inteligentes , Humanos , Biomimética
12.
Antonie Van Leeuwenhoek ; 114(8): 1213-1224, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34002321

RESUMEN

A novel Gram-stain-negative, aerobic and rod-shaped bacterium with a single polar flagellum or a stalk at the end of the cell, was isolated from maize roots in the Fangshan District of Beijing, People's Republic of China. The new strain designated 774T produced indole acetic acid (IAA). The 16S rRNA gene sequence analysis indicated that strain 774T belongs to the genus Caulobacter and is closely related to Caulobacter flavus RHGG3T, Caulobacter zeae 410Tand Caulobacter radices 695T, all with sequence similarities of 99.9%. The genome size of strain774T was 5.4 Mb, comprising 5042 predicted genes with a DNA G+C content of 68.7%.Three striking lasso peptide biosynthetic gene clusters and two IAA synthesis genes belonging to the TPM pathway were also found in the genome of strain 774T. The average nucleotide identity values and digital DNA-DNA hybridization values of the strain774T with its closely phylogenetic neighbours were less than 91.5% and 45.0%, respectively, indicating a new Caulobacter species. The major fatty acids of strain774T were identified as C16: 0 (27.7%), summed feature 3 (C16: 1ω6c and/or C16: 1ω7c) (12.6%) and summed feature 8 (C18: 1ω7c and/or C18: 1ω6c) (42.9%).The major polar lipids consisted of phosphatidyl-glycerol and glycolipids. The predominant ubiquinone was identified as Quinone 10. Based on the polyphasic characterization, strain 774T represents a novel species of the genus Caulobacter, for which the name Caulobacter endophyticus sp. nov. is proposed with 774T (= CGMCC 1.16558T = DSM 106777T) as the type strain.


Asunto(s)
Caulobacter , Zea mays , Técnicas de Tipificación Bacteriana , Caulobacter/genética , ADN Bacteriano/genética , Ácidos Grasos/análisis , Humanos , Ácidos Indolacéticos , Familia de Multigenes , Péptidos , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Microbiología del Suelo , Ubiquinona
13.
Int J Syst Evol Microbiol ; 70(10): 5531-5538, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32915126

RESUMEN

Two nifH gene-harbouring bacterial strains were isolated from rhizospheres of different vegetable plants grown in different regions of northern PR China. The two strains possessed almost identical 16S rRNA gene sequences. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the two strains were 99.21 and 93.6% respectively, suggesting they belong to one species. Based on 16S rRNA gene phylogeny, the two strains were clustered together with Paenibacillus rhizophilus 7197T, Paenibacillus sabinae T27T and Paenibacillus forsythiae T98T, but on a separate branch. Novelty of the species was confirmed by ANI and dDDH comparisons between the type strain 7124T and its closest relatives, since the obtained values were considerably below the proposed thresholds for the species delineation. The genome size of strain 7124T was 5.40 Mb, comprising 5050 predicted genes with a DNA G+C content of 52.3 mol%. The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unidentified lipids. The major cellular fatty acids were anteiso-C15  :  0 (52.9%) and C16  :  0 (23.4 %). Menaquinone-7 was reported as the major respiratory quinone. The diamino acid in the cell-wall peptidoglycan was found to be meso-diaminopimelic acid. Based on phylogenetic, genomic, chemotaxonomic and phenotypic data, the two isolates are considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus apii sp. nov. is proposed, with 7124T (=DSM 103172T=CGMCC 1.15689T) as type strain.


Asunto(s)
Paenibacillus/clasificación , Filogenia , Rizosfera , Microbiología del Suelo , Verduras/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Paenibacillus/aislamiento & purificación , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
14.
Int J Syst Evol Microbiol ; 70(9): 5019-5025, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32783806

RESUMEN

A novel Gram-stain-negative, aerobic, rod-shaped and indole acetic acid-producing strain, designated 7209-2T, was isolated from rhizosphere of rape (Brassica napus L.) grown in the Yakeshi City, Inner Mongolia, PR China. The 16S rRNA gene sequence analysis indicated that strain 7209-2T belongs to the genus Rhizobium and is closely related to Rhizobium rosettiformans W3T, Rhizobium ipomoeae shin9-1T and Rhizobium wuzhouense W44T with sequence similarities of 98.2, 98.1 and 97.9 %, respectively. Phylogenetic analysis based on concatenated housekeeping recA and atpD gene sequences showed that strain 7209-2T formed a group together with R. wuzhouense W44T and R. rosettiformans W3T, with sequences similarities of 92.6 and 91.1 %, respectively. The genome size of strain 7209-2T was 5.25 Mb, comprising 5027 predicted genes with a DNA G+C content of 61.2 mol%. The average nucleotide identity and digital DNA-DNA hybridization comparisons among 7209-2T and reference strains for the most closely related species showed values below the accepted threshold for species discrimination. The major fatty acids of strain 7209-2T were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and summed feature 2 (C12 : 0 aldehyde and/or unknown 10.953) . The major polar lipids were found to consist of phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and an unidentified aminophospholipid. The predominant ubiquinone was identified as quinone 10. Based on all the above results, strain 7209-2T represents a novel species of the genus Rhizobium, for which the name Rhizobium rhizophilum sp. nov. is proposed with 7209-2T (=CGMCC 1.15691T=DSM 103161T) as the type strain.


Asunto(s)
Brassica napus/microbiología , Ácidos Indolacéticos/metabolismo , Filogenia , Rhizobium/clasificación , Rizosfera , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Rhizobium/aislamiento & purificación , Análisis de Secuencia de ADN , Ubiquinona/análogos & derivados , Ubiquinona/química
15.
Antonie Van Leeuwenhoek ; 113(8): 1179-1189, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32468221

RESUMEN

A novel 1-aminocyclopropane-1-carboxylate deaminase producing bacterium, Gram- stain-negative, aerobic, motile, rod-shaped strain designated YM1C-6-2T was isolated from rhizosphere of maize grown in Northeast China. The 16S rRNA gene sequence analysis indicated that strain YM1C-6-2T belongs to the genus Mesorhizobium and is closely related to Mesorhizobium alhagi CCNWXJ12-2T and M. camelthorni CCNWXJ40-4T with sequence similarities of 98.4% and 97.9%, respectively. Multilocus sequence analysis of other housekeeping genes revealed that the new isolates YM1C-6-2T forms a phylogenetically group with some species in the genus Mesorhizobium. The genome size of strain YM1C-6-2T was 5.51 Mb, comprising 5378 predicted genes with a DNA G+C content of 64.5%. The average nucleotide identity and digital DNA-DNA hybridization comparisons between YM1C-6-2T and the most related type strains showed values below the accepted threshold for species discrimination. The major fatty acids of strain YM1C-6-2T were C19:0 cyclo ω8c (47.5%), summed feature 8 (C18:1ω7c and/or C18:1ω6c) (19.5%) and C16:0 (15.1%), which differed from the closely related reference strains in their relative abundance. The major polar lipids consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and an unidentified aminophospholipid. The predominant ubiquinone was identified as Quinone 10. Phenotypic and biochemical analysis results indicated that strain YM1C-6-2T can be distinguished from closely related type strains. Based on the above results, strain YM1C-6-2T represents a novel species of the genus Mesorhizobium, for which the name Mesorhizobium rhizophilum sp. nov. is proposed with YM1C-6-2T (= CGMCC 1.15487T = DSM 101712T) as the type strain.


Asunto(s)
Liasas de Carbono-Carbono/biosíntesis , Mesorhizobium/clasificación , Mesorhizobium/enzimología , Mesorhizobium/aislamiento & purificación , Filogenia , Rizosfera , Zea mays/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/análisis , Mesorhizobium/genética , Fosfatidiletanolaminas , Microbiología del Suelo , Ubiquinona/química
16.
Biochem Biophys Res Commun ; 515(2): 352-358, 2019 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-31153636

RESUMEN

Obesity-associated insulin resistance is a forerunner of type 2 diabetes. Macrophages reside within adipose tissue (ATMs) have been reported to regulate insulin sensitivity through secreting miRNAs containing exosomes. Here, we show that miR-29a is increased in obese ATMs derived exosomes (ATMs-Exos) and can be transferred into adipocytes, myocytes and hepatocytes causing insulin resistance in vitro and in vivo. Administration of obese ATMs-Exos impairs insulin sensitivity of lean mice. While knockdown miR-29a level in obese ATM-Exos blunts this effect. PPAR-δ is identified to function as downstream target of miR-29a in regulating insulin resistance. PPAR-δ agonist GW501516 partially rescued the insulin resistance induced by miR-29a. Taken together, these findings suggest that ATMs derived exosomal miR-29a could regulate obesity-associated insulin resistance, which may serve as a potential therapeutic target for obesity-associated type 2 diabetes.


Asunto(s)
Tejido Adiposo/metabolismo , Resistencia a la Insulina/fisiología , Macrófagos/metabolismo , MicroARNs/metabolismo , Obesidad/metabolismo , Adipocitos/metabolismo , Animales , Diabetes Mellitus Tipo 2/etiología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animales de Enfermedad , Exosomas/genética , Exosomas/metabolismo , Técnicas de Silenciamiento del Gen , Hepatocitos/metabolismo , Técnicas In Vitro , Resistencia a la Insulina/genética , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Células Musculares/metabolismo , Obesidad/complicaciones , Obesidad/genética , Receptores Citoplasmáticos y Nucleares/agonistas , Receptores Citoplasmáticos y Nucleares/metabolismo , Tiazoles/farmacología
18.
Phytother Res ; 30(12): 1937-1942, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27539187

RESUMEN

Yacon (Smallanthus sonchifolius), a traditional food in the Andean diet, is attracting global attention for its medicinal properties, which are mainly because of its high content of non-digestible oligosaccharides. The purpose of this study is to evaluate the antidepressant-like effects of inulin-type oligosaccharides extracted from yacon (YOs) in behavioral models of depression. Behavioral despair models in mice including the tail suspension test (TST) and the forced swimming test (FST) were used to determine the effects of acute YOs administration. The locomotor activity was also explored to eliminate any false-positive activity. In addition, to further investigate the antidepressant-like effects of subchronic YOs administration, the learned helplessness (LH) paradigm in rats was performed. The results demonstrated that YOs (25, 50, or 100 mg/kg, p.o.) treatment significantly reduced the immobility time in the mouse TST and FST in a U-shaped, dose-dependent manner, and showed no stimulatory effect on the locomotor activity. Furthermore, subchronic YOs (25, 50, or 100 mg/kg, p.o.) treatment significantly reversed the escape deficits in LH rats, including an increased number of escape failures and prolonged escape latency. These findings suggest that the inulin-type oligosaccharides extracted from yacon may be a prospective natural source for antidepressants. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Asteraceae/química , Trastorno Depresivo/tratamiento farmacológico , Inulina/farmacología , Oligosacáridos/farmacología , Animales , Antidepresivos/aislamiento & purificación , Antidepresivos/farmacología , Trastorno Depresivo/etiología , Modelos Animales de Enfermedad , Suspensión Trasera/métodos , Masculino , Ratones , Oligosacáridos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Estudios Prospectivos , Ratas , Ratas Sprague-Dawley
19.
Mol Genet Genomics ; 290(4): 1357-65, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25647731

RESUMEN

Body weight regulation is influenced neuronally via the hypothalamus, which strongly expresses TRPV4. TRPV4 deficiency in mice confers resistance against diet-induced obesity. We investigated the association between TRPV4 gene variants and body mass index (BMI) in Taiwanese subjects. A sample population of 617 Taiwanese subjects was enrolled, and ten TRPV4 gene polymorphisms were selected and genotyped. After adjusting for clinical covariates, significant associations were observed between three studied polymorphisms and BMI using a dominant model (P = 4.83 × 10(-4), P = 1.17 × 10(-4), and P = 3.37 × 10(-4) for rs3742037, rs10735104, and rs3742035, respectively). Obesity as defined according to both the Asian and National Institutes of Health (NIH) criteria was significantly associated with rs10735104 (P = 0.003 and P = 0.037, respectively) in a dominant model. Genotypes at the TRPV4 locus independently affect BMI and obesity status in Taiwanese subjects. This association may broaden our understanding of the role of neuronal influence on body weight regulation. The regulation of TRPV4 channels in skeletal muscle and adipose tissue could also be a new therapeutic target for preventing the development of obesity.


Asunto(s)
Índice de Masa Corporal , Predisposición Genética a la Enfermedad/genética , Obesidad/genética , Polimorfismo de Nucleótido Simple , Canales Catiónicos TRPV/genética , Adulto , Pueblo Asiatico/genética , Peso Corporal/genética , Proteína C-Reactiva/metabolismo , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/etnología , Genotipo , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Obesidad/sangre , Obesidad/etnología , Taiwán , Triglicéridos/sangre
20.
Int J Mol Sci ; 15(12): 22421-37, 2014 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-25486056

RESUMEN

YKL-40, a pleotropic cytokine, is emerging as a risk factor and a prognostic predictor of atherosclerotic cardiovascular disease. We attempted to elucidate the genetic, clinical and biochemical correlates of circulating YKL-40 level and, by combining it with CHI3L1 gene variants, with the risk and long-term mortality of peripheral artery disease (PAD). Plasma YKL-40 concentrations were measured in 612 Taiwanese individuals who had no clinically overt systemic disease. Clinical parameters, CHI3L1 gene promoter variants and 18 biomarker levels were analyzed. Eighty-six PAD patients were further enrolled for analysis. Significant associations were found between CHI3L1 genotypes/haplotypes and YKL-40 levels for the health examination subjects (smallest p = 8.36 × 10-7 for rs4950928 and smallest p = 1.72 × 10-10 for haplotype TGG) and also for PAD patients. For the health examination subjects, circulating YKL-40 level, but not CHI3L1 gene variants, were positively associated with age, smoking, and circulating levels of triglyceride, lipocalin 2 and multiple inflammatory biomarkers and negatively associated with low-density-lipoprotein cholesterol levels. Circulating YKL-40 level is also significantly associated with the risk of PAD (p = 3.3 × 10-23). Circulating YKL40 level, but not CHI3L1 gene promoter variants, is associated with the risk of PAD in Taiwanese. The association of YKL-40 levels with multiple quantitative traits relating to the risk of PAD may provide a molecular basis linking YKL-40 to atherosclerotic cardiovascular disease.


Asunto(s)
Adipoquinas/sangre , Adipoquinas/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Lectinas/sangre , Lectinas/genética , Enfermedad Arterial Periférica/genética , Polimorfismo de Nucleótido Simple/genética , Carácter Cuantitativo Heredable , Biomarcadores/sangre , Proteína 1 Similar a Quitinasa-3 , Demografía , Femenino , Sitios Genéticos , Haplotipos/genética , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Arterial Periférica/mortalidad , Examen Físico , Factores de Riesgo
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