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1.
Sensors (Basel) ; 23(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37430853

RESUMO

Wearable surface electromyography (sEMG) signal-acquisition devices have considerable potential for medical applications. Signals obtained from sEMG armbands can be used to identify a person's intentions using machine learning. However, the performance and recognition capabilities of commercially available sEMG armbands are generally limited. This paper presents the design of a wireless high-performance sEMG armband (hereinafter referred to as the α Armband), which has 16 channels and a 16-bit analog-to-digital converter and can reach 2000 samples per second per channel (adjustable) with a bandwidth of 0.1-20 kHz (adjustable). The α Armband can configure parameters and interact with sEMG data through low-power Bluetooth. We collected sEMG data from the forearms of 30 subjects using the α Armband and extracted three different image samples from the time-frequency domain for training and testing convolutional neural networks. The average recognition accuracy for 10 hand gestures was as high as 98.6%, indicating that the α Armband is highly practical and robust, with excellent development potential.


Assuntos
Antebraço , Gestos , Humanos , Eletromiografia , Intenção , Aprendizado de Máquina
2.
Nat Prod Res ; 33(9): 1257-1261, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29770711

RESUMO

The chemical constituents of the fungus Verticillium psalliotae were studied. Two new aromadendrane sesquiterpenes inonotin M (1) and inonotin N (2) were isolated from the EtOAc extract of the fungal culture broth. The structures of compounds were elucidated mainly by HRESIMS experiments, and 1D, 2D-NMR spectroscopy analysis.


Assuntos
Sesquiterpenos/isolamento & purificação , Verticillium/química , Espectroscopia de Ressonância Magnética , Sesquiterpenos/química , Sesquiterpenos de Guaiano
3.
Int J Syst Evol Microbiol ; 68(8): 2574-2579, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29944093

RESUMO

A Gram-staining-negative, aerobic, motile and rod-shaped bacterium, designated strain X1-8T, was isolated from rhizosphere soil of Nicotiana tabacum L. collected from the tobacco produce base located in Kunming, south-west PR China. Cells showed oxidase-negative and catalase-positive reactions and were motile by means of peritrichous flagella. Growth occurred at 25-40 °C and pH 6.0-8.0 with optimal growth at 30-35 °C, pH 7.0. The major respiratory lipoquinone was Q-10. C16 : 0 and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) were identified as major cellular fatty acids. The profile of polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, sphingoglycolipid, phosphatidylcholine and one unidentified glycolipid. The major polyamine was sym-homospermidine. The genomic DNA G+C content was 66.5 mol%. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that X1-8T should be affiliated to the genus Sphingomonasand formed a clade with most closely related species Sphingomonas changbaiensisNBRC 104936T. The results of 16S rRNA gene sequences similarity analysis indicated that X1-8T had the highest similarity with S. changbaiensisNBRC 104936T (98.4 %) and lower than 96.0 % with other species of the genus Sphingomonas. DNA-DNA hybridization data indicated that X1-8T represented a novel genomic species of the genus Sphingomonas. The characteristics determined in the polyphasic taxonomic study indicated that X1-8T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas tabacisoli sp. nov. (type strain X1-8T=KCTC 62032T=CGMCC 1.16275T) is proposed.


Assuntos
Nicotiana/microbiologia , Filogenia , Rizosfera , Microbiologia do Solo , Sphingomonas/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espermidina/análogos & derivados , Espermidina/química , Sphingomonas/genética , Sphingomonas/isolamento & purificação , Ubiquinona/química
4.
Antonie Van Leeuwenhoek ; 108(5): 1161-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26346479

RESUMO

A Gram-stain negative, motile, rod-shaped bacterium, designated strain YIM Hb-3(T), was isolated from the stem of a tobacco plant. The strain was observed to form convex, circular and yellow-colored colonies. The predominant respiratory quinone was identified as Q-8. The major fatty acids (>5%) detected were C(16:1)ω7c and/or C(16:1)ω6c (summed feature 3), C(16:0), C(17:0)cyclo, C(18:1)ω7c and/or C(18:1)ω6c (summed feature 8), C(14:0)3-OH and/or iso-C(16:1)I (summed feature 2), C(14:0) and C(12:0). The genomic DNA G+C content was determined to be 54.8 mol%. Phylogenetic trees based on 16S rRNA gene sequences and multilocus sequence analysis showed that strain YIM Hb-3(T) had the closest phylogenetic relationship with Enterobacter mori LMG 25706(T). DNA-DNA relatedness value between strain YIM Hb-3(T) and E. mori LMG 25706(T) was 46.9 ± 3.8%. On the basis of phenotypic and chemotaxonomic data, phylogenetic analysis, and DNA-DNA relatedness value, strain YIM Hb-3(T) is considered to represent a novel species of the genus Enterobacter, for which the name Enterobacter tabaci sp. nov. is proposed. The type strain is YIM Hb-3(T) (=KACC 17832(T) =KCTC 42694(T)).


Assuntos
Enterobacter/classificação , Nicotiana/microbiologia , Caules de Planta/microbiologia , Enterobacter/química , Enterobacter/genética , Enterobacter/isolamento & purificação , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética
5.
J Asian Nat Prod Res ; 17(9): 876-81, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26411648

RESUMO

Three new isocoumarins, terrecoumarins A-C (1-3), together with six known isocoumarins (4-9) were isolated from the fermentation products of the fungus Penicillium oxalicum 0403. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. The anti-tobacco mosaic virus (anti-TMV) activities of 1-9 were evaluated. The results revealed that compound 1 showed high anti-TMV activity with inhibition rate 25.4 ± 3.5%. Other compounds also showed weak activity with inhibition rate in the range of 11.3-18.9%.


Assuntos
Antivirais/isolamento & purificação , Antivirais/farmacologia , Isocumarinas/isolamento & purificação , Penicillium/química , Antivirais/química , Fermentação , Isocumarinas/química , Isocumarinas/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Vírus do Mosaico do Tabaco/efeitos dos fármacos
6.
Bioprocess Biosyst Eng ; 38(2): 399-405, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25218329

RESUMO

This study aimed to improve the production of polysaccharide by engineering the biosynthetic pathway in Ganoderma lucidum through the overexpression of α-phosphoglucomutase (PGM) gene. PGM is responsible for the linkage between sugar catabolism and sugar anabolism. The effects of PGM gene overexpression on intracellular polysaccharide (IPS) content, extracellular polysaccharide (EPS) production and transcription levels of three genes encoding the enzymes involved in polysaccharide biosynthesis, including PGM, UDP-glucose pyrophosphorylase (UGP), and ß-1,3-glucan synthase (GLS), were investigated. The maximum IPS content and EPS production in G. lucidum overexpressing the PGM gene were 23.67 mg/100 mg dry weight and 1.76 g/L, respectively, which were higher by 40.5 and 44.3% than those of the wild-type strain. The transcription levels of PGM, UGP and GLS were upregulated by 4.77-, 1.51- and 1.53-fold, respectively, in the engineered strain, suggesting that increased polysaccharide biosynthesis may result from a higher expression of those genes.


Assuntos
Reatores Biológicos/microbiologia , Genes Sintéticos/genética , Melhoramento Genético/métodos , Fosfoglucomutase/fisiologia , Polissacarídeos/biossíntese , Reishi/fisiologia , Recombinação Homóloga/genética , Polissacarídeos/genética , Polissacarídeos/isolamento & purificação , Regulação para Cima/genética
7.
Antonie Van Leeuwenhoek ; 106(6): 1199-205, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25239270

RESUMO

A Gram-stain positive, facultative anaerobic endospore-forming bacterium, designated strain YIM h-19(T), was isolated from a tobacco sample. Cells were observed to be motile rods by means of peritrichous flagella and colonies were observed to be convex, yellow, circular and showed catalase-positive and oxidase-negative reactions. Strain YIM h-19(T) was able to grow at 4-45 °C, pH 6.0-8.0 and 0-3 % NaCl (w/v). The predominant respiratory quinone was identified as MK-7. Major fatty acids were identified as anteiso-C15:0, anteiso-C17:0 and C16:0. The polar lipids were found to be phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and two unidentified polar lipids. The genomic DNA G+C content was determined to be 54 mol%. 16S rRNA gene sequence analysis showed the strain YIM h-19(T) was most closely related to Paenibacillus hordei RH-N24(T) and Paenibacillus hunanensis FeL05(T) with similarities of 98.30 and 94.64 % respectively. However, DNA-DNA hybridization data indicated that the isolate represented a novel genomic species with the genus Paenibacillus. All data from genotypic and phenotypic analyses support the conclusion that strain YIM h-19(T) represents a novel species of the genus Paenibacillus, for which the name Paenibacillus nicotianae sp. nov. is proposed. The type strain is YIM h-19(T) (=CGMCC1.12819(T) = NRRL B-59112(T)).


Assuntos
Nicotiana/microbiologia , Paenibacillus/classificação , Paenibacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Concentração de Íons de Hidrogênio , Locomoção , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Paenibacillus/genética , Paenibacillus/fisiologia , Fosfolipídeos/análise , Filogenia , Quinonas/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Temperatura
8.
Chem Biodivers ; 10(11): 2021-31, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24243611

RESUMO

The biotransformation of the major saponins in Panax notoginseng, including the ginsenosides Rg1, Rh1, Rb1, and Re, by endophytes isolated from P. notoginseng was studied. One hundred and thirty-six endophytes were isolated and screened for their biotransformational abilities. The results showed that five of the tested endophytes were able to transform these saponins. These five strains were identified based on their ITS or 16S rDNA sequences, which revealed that they belonged to the genera Fusarium, Nodulisporium, Brevundimonas, and Bacillus genera. Ten transformed products were isolated and identified, including a new compound 6-O-[α-L-rhamnopyranosyl-(1→2)-ß-D-glucopyranosyl]-20-O-ß-D-glucopyranosyldammarane-3,6,12,20,24,25-hexaol (3), and nine known compounds, compound K (1), ginsenoside F2 (2), vinaginsenoside R13 (4), vinaginsenoside R22 (5), pseudo-ginsenoside RT4 (6), (20S)-protopanaxatriol (7), ginsenoside Rg1 (8), vinaginsenoside R15 (9), and (20S)-3-O-ß-D-glucopyranosyl-6-O-ß-D-glucopyranosylprotopanaxatriol (10). This is the first study on the biotransformation of chemical components in P. notoginseng by endophytes isolated from the same plant.


Assuntos
Endófitos/metabolismo , Panax notoginseng/metabolismo , Panax notoginseng/microbiologia , Saponinas/metabolismo , Biotransformação , Endófitos/genética , Endófitos/isolamento & purificação , Panax notoginseng/química , Saponinas/análise
9.
Chem Biodivers ; 7(7): 1790-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20658667

RESUMO

A fungal strain named MFF-1 was isolated from the flower of Pyrethrum cinerariifolium. Based on the sequence at the internal transcribed spacer (ITS) region, this strain was identified as a Trichoderma sp. Two new compounds, including a mitorubrin derivative and its potential biogenetic precursor, together with a known compound, were isolated from the cultures of the endophytic fungus. Their structures were established by spectroscopic methods and determined to be (3S*,6R*,7R*)-3,4,5,6,7,8-hexahydro-7-hydroxy-7-methyl-8-oxo-3-[(E)-prop-1-enyl]-1H-isochromen-6-yl 2,4-dihydroxy-6-methylbenzoate (1), named deacetylisowortmin, (E)-2-(hydroxymethyl)-3-(2-hydroxypent-3-enyl)phenol (2), and wortmannin (3). All compounds were assayed for antimicrobial activity. Compound 3 showed activity against Candida albicans and Bacillus cereus.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Chrysanthemum cinerariifolium/parasitologia , Trichoderma/química , Anti-Infecciosos/isolamento & purificação , Bacillus cereus/efeitos dos fármacos , Benzoatos/química , Benzoatos/isolamento & purificação , Benzoatos/farmacologia , Candida albicans/efeitos dos fármacos , Flores/parasitologia , Testes de Sensibilidade Microbiana , Trichoderma/isolamento & purificação
10.
Nat Prod Res ; 23(15): 1431-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19809916

RESUMO

Two new cyclopentenones, trichodermone A (1) and trichodermone B (2), together with a known compound, 3-(3-oxocyclopent-1-enyl) propanoic acid (3), were isolated from the strain Trichoderma sp. YLF-3. Their structures were elucidated on the basis of their spectroscopic data. All compounds were assayed for antibacterial activity. Compound 3 showed activity against Staphyloccocus aureus and Bacillus cereus.


Assuntos
Ciclopentanos/química , Ciclopentanos/farmacologia , Trichoderma/química , Antibacterianos/química , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Biologia Molecular , Staphylococcus aureus/efeitos dos fármacos
11.
Chem Biodivers ; 6(3): 431-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19319871

RESUMO

Three nematicidal cardenolides were obtained from the AcOEt extract of Nerium indicum Mill. by bioassay-guided fractionation. They include a new compound, 3beta-O-(beta-D-diginosyl)-14,15alpha-dihydroxy-5alpha-card-20(22)-enolide (1), and two known compounds, uzarigenin (2) and cardenolide N-1 (3). The median lethal concentrations (LC(50)) of compounds 1-3 against the nematodes Bursaphelenchus xylophilus, Panagrellus redivivus, and Caenorhabditis elegans at 72 h were 103.3, 49.0, and 45.4 mg l(-1), 257.0, 62.7, and 177.8 mg l(-1), and 242.9, 29.1, and 41.7 mg l(-1), respectively. This is the first report about the nematicidal activity of cardenolides.


Assuntos
Antinematódeos/isolamento & purificação , Cardenolídeos/isolamento & purificação , Nerium/química , Animais , Antinematódeos/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Cardenolídeos/farmacologia , Dose Letal Mediana , Nematoides/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular
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