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1.
Sensors (Basel) ; 24(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38610573

RESUMO

A force plate is mainly used in biomechanics; it aims to measure the ground reaction force in a person's walking or standing position. In this study, a large-area force mat of the piezoresistance sensing type was developed, and a deep-learning-based weight measurement calibration method was applied to solve the problem in which measurements are not normalized because of physical limitations in hardware and signal processing. The test set was composed of the values measured at each point by weight and the value of the center of the pressure variable, and the measured value was predicted using a deep neural network (DNN) regression model. The calibration verification results show that the average weight errors range from a minimum of 0.06% to a maximum of 3.334%. This is simpler than the previous method, which directly measures the ratio of the resistance value to the measured weight of each sensor and derives an equation.

2.
Nano Lett ; 23(8): 3582-3591, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37027522

RESUMO

Over the past decade, lithium metal has been considered the most attractive anode material for high-energy-density batteries. However, its practical application has been hindered by its high reactivity with organic electrolytes and uncontrolled dendritic growth, resulting in poor Coulombic efficiency and cycle life. In this paper, we propose a design strategy for interface engineering using a conversion-type reaction of metal fluorides to evolve a LiF passivation layer and Li-M alloy. Particularly, we propose a LiF-modified Li-Mg-C electrode, which demonstrates stable long-term cycling for over 2000 h in common organic electrolytes with fluoroethylene carbonate (FEC) additives and over 700 h even without additives, suppressing unwanted side reactions and Li dendritic growth. With the help of phase diagrams, we found that solid-solution-based alloying not only facilitates the spontaneous evolution of a LiF layer and bulk alloy but also enables reversible Li plating/stripping inward to the bulk, compared with intermetallic compounds with finite Li solubility.

3.
Mar Drugs ; 21(2)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36827121

RESUMO

Although the tumor bulk is initially reduced by 5-fluorouracil (5-FU), chemoresistance developed due to prolonged chemotherapy in colorectal cancer (CRC). The enrichment of cancer stem cells (CSCs) and the infiltration of tumor-associated macrophages (TAMs) contribute to chemoresistance and poor outcomes. A docosahexaenoic acid derivative developed by our group, 7S,15R-dihydroxy-16S,17S-epoxy-docosapentaenoic acid (diHEP-DPA), exerts antitumor effects against TAMs infiltration and CSCs enrichment in our previous study. The current study aimed to investigate whether diHEP-DPA was able to overcome chemoresistance to 5-FU in CRCs, together with the potential synergistic mechanisms in a CT26-BALB/c mouse model. Our results suggested that although 5-FU inhibited tumor growth, 5-FU enriched CSCs via the WNT/ß-catenin signaling pathway, resulting in chemoresistance in CRCs. However, we revealed that 5-FU promoted the infiltration of TAMs via the NF-kB signaling pathway and improved epithelial-mesenchymal transition (EMT) via the signal transducer and activator of the transcription 3 (STAT3) signaling pathway; these traits were believed to contribute to CSC activation. Furthermore, supplementation with diHEP-DPA could overcome drug resistance by decreasing the CSCs, suppressing the infiltration of TAMs, and inhibiting EMT progression. Additionally, the combinatorial treatment of diHEP-DPA and 5-FU effectively enhanced phagocytosis by blocking the CD47/signal regulatory protein alpha (SIRPα) axis. These findings present that diHEP-DPA is a potential therapeutic supplement to improve drug outcomes and suppress chemoresistance associated with the current 5-FU-based therapies for colorectal cancer.


Assuntos
Neoplasias Colorretais , Fluoruracila , Camundongos , Animais , Humanos , Fluoruracila/farmacologia , Resistencia a Medicamentos Antineoplásicos , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , Xenoenxertos , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Via de Sinalização Wnt , Células-Tronco Neoplásicas
4.
Angew Chem Int Ed Engl ; 62(48): e202312928, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37842904

RESUMO

High-capacity Li-rich layered oxides using oxygen redox as well as transition metal redox suffer from its structural instability due to lattice oxygen escaped from its structure during oxygen redox and the following electrolyte decomposition by the reactive oxygen species. Herein, we rescued a Li-rich layered oxide based on 4d transition metal by employing an organic superoxide dismutase mimics as a homogeneous electrolyte additive. Guaiacol scavenged superoxide radicals via dismutation or disproportionation to convert two superoxide molecules to peroxide and dioxygen after absorbing lithium superoxide on its partially negative oxygen of methoxy and hydroxyl groups. Additionally, guaiacol was decomposed to form a thin and stable cathode-electrolyte interphase (CEI) layer, endowing the cathode with the interfacial stability.

5.
Nanotechnology ; 34(9)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36541520

RESUMO

Tunnel field-effect transistors (TFETs) have garnered great interest as an option for the replacement of metal-oxide-semiconductor field-effect transistors owing to their extremely low off-current and fast switching suitable for low-power-consumption applications. However, conventional doped TFETs have the disadvantage of introducing undesirable random dopant fluctuation (RDF) events, which cause a large variance in the threshold voltage and ambipolar leakage current at negative gate voltages. In this study, a simple approach for charge plasma-based doping-less TFETs (DL-TFETs), including the Ge/Si bilayer frame, which affects the RDF and low on-current issues, was developed by the commercially available Silvaco Atlas device simulator. The use of the Ge/Si bilayer enhances the on-current and point subthreshold swing to 1.4 × 10-6A and 16.6 mV dec-1, respectively. In addition, the dependencies of the Ge/Si junction boundary position and Ge content were examined systematically to attain a firm understanding of the electrical features in DL-TFETs.

6.
Sensors (Basel) ; 22(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36433479

RESUMO

The Wii balance board (WBB) is a simplified force plate system used to evaluate the balancing ability of the elderly via a sensory interaction task to confirm a significant standing balance index. The accuracy of this system has been verified in previous studies. In this study, an instrumented and modified clinical test of sensory interaction on balance (i-mCTSIB) was performed on 84 elderly subjects, and the variables for center of pressure (CoP) were calculated using WBB for each task condition. The results indicate that the visual condition has a significant effect on the sway proprioceptive sensory variables with a foam condition as their complexity increases. In addition, the correlation between the variable and Berg Balance Scale was not confirmed since CTSIB is a sensory interaction on balance ability. Therefore, WBB can be used to evaluate balancing ability based on sensory interactions consisting of the surface condition.


Assuntos
Jogos de Vídeo , Humanos , Idoso , Equilíbrio Postural , Propriocepção
7.
Sensors (Basel) ; 21(5)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801552

RESUMO

The prototype machine of gait training and rehabilitation (MGTR) with a five-bar linkage structure was designed to improve the common end-effector type. Additionally, the study was conducted to evaluate the joint angle and muscle activity during walking for the evaluation of prototype: (1) Background: The gait rehabilitation systems are largely divided into exoskeletal type and end-effector type. The end-effector type can be improved a gait trajectory similar to normal gait according to this prototype. Therefore, a new design of prototype MGTR is proposed in this study. (2) Methods: The gait experience was conducted with thirteen healthy male subjects using an inertial measurement unit (IMU) sensor and electromyography (EMG). It was compared that the hip and knee joints and the muscle activity between the normal gait and MGTR. (3) Results: The results showed that there was a high correlation between the knee joint angle for normal gait and MGTR. The range of motion (RoM) was small for the MGTR. The EMG results showed that the activation of the rectus femoris muscle was most similar to the normal gait and MGTR. (4) Conclusions: The characteristics of the kinematic variables of the subjects varied widely. It is necessary to modify the machine so that the link length can be adjusted in consideration of various segment lengths of patients.


Assuntos
Marcha , Caminhada , Fenômenos Biomecânicos , Eletromiografia , Humanos , Articulação do Joelho , Masculino , Músculo Esquelético , Amplitude de Movimento Articular
8.
Sensors (Basel) ; 21(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34883786

RESUMO

Non-invasive measurement of physiological parameters and indicators, specifically among the elderly, is of utmost importance for personal health monitoring. In this study, we focused on photoplethysmography (PPG), and developed a regression model that calculates variables from the second (SDPPG) and third (TDPPG) derivatives of the PPG pulse that can observe the inflection point of the pulse wave measured by a wearable PPG device. The PPG pulse at the earlobe was measured for 3 min in 84 elderly Korean women (age: 71.19 ± 6.97 years old). Based on the PPG-based cardiovascular function, we derived additional variables from TDPPG, in addition to the aging variable to predict the age. The Aging Index (AI) from SDPPG and Sum of TDPPG variables were calculated in the second and third differential forms of PPG. The variables that significantly correlated with age were c/a, Tac, AI of SDPPG, sum of TDPPG, and correlation coefficient 'r' of the model. In multiple linear regression analysis, the r value of the model was 0.308, and that using deep learning on the model was 0.839. Moreover, the possibility of improving the accuracy of the model using supervised deep learning techniques, rather than the addition of datasets, was confirmed.


Assuntos
Fotopletismografia , Dispositivos Eletrônicos Vestíveis , Idoso , Envelhecimento , Feminino , Frequência Cardíaca , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador
9.
Biochem Biophys Res Commun ; 533(4): 893-898, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33008591

RESUMO

Lipoxygenases (LOXs) are implicated in the biosynthesis of pro- and anti-inflammatory lipid mediators involved in immune cell signaling, most of which catalyze peroxidation of polyunsaturated fatty acids by distinct regio- and stereoselectivity. Current reports suggested that conserved amino acid, Gly in R-LOXs and Ala in S-LOXs, in the catalytic domain play an important role in determining the position as well as the stereochemistry of the functional group. Recently, we have confirmed that the catalytic specificity of cyanobacterial lipoxygenase, named Osc-LOX, with alanine at 296 was 13S-type toward linoleic acid, and producing a 17S- hydroxy-docosahexaenoic acid from docosahexaenoic acid (DHA). Here, we aimed to change the catalytic property of LOX from13S-LOX to 9R-LOX by replacing Ala with Gly and to produce a lipid mediators different from the wild-type using DHA. Finally, we succeeded in generating human endogenous a 13R-hydroxy-docosahexaenoic acid and a 13R,20-dihydroxy-docosahexaenoic acid from DHA through an enzymatic reaction using the Osc-LOX-A296G. Our study could enable physiological studies and pharmaceutical research for the 13R,20-dihydroxy-docosahexaenoic acid.


Assuntos
Lipoxigenases/genética , Lipoxigenases/metabolismo , Oscillatoria/enzimologia , Ácidos Docosa-Hexaenoicos/metabolismo , Humanos , Lipoxigenases/química , Mutagênese Sítio-Dirigida , Estereoisomerismo
10.
Microb Cell Fact ; 19(1): 6, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931797

RESUMO

BACKGROUND: 1,3-propanediol (1,3-PDO) is the most widely studied value-added product that can be produced by feeding glycerol to bacteria, including Lactobacillus sp. However, previous research reported that L. reuteri only produced small amounts and had low productivity of 1,3-PDO. It is urgent to develop procedures that improve the production and productivity of 1,3-PDO. RESULTS: We identified a novel L. reuteri CH53 isolate that efficiently converted glycerol into 1,3-PDO, and performed batch co-fermentation with glycerol and glucose to evaluate its production of 1,3-PDO and other products. We optimized the fermentation conditions and nitrogen sources to increase the productivity. Fed-batch fermentation using corn steep liquor (CSL) as a replacement for beef extract led to 1,3-PDO production (68.32 ± 0.84 g/L) and productivity (1.27 ± 0.02 g/L/h) at optimized conditions (unaerated and 100 rpm). When CSL was used as an alternative nitrogen source, the activity of the vitamin B12-dependent glycerol dehydratase (dhaB) and 1,3-propanediol oxidoreductase (dhaT) increased. Also, the productivity and yield of 1,3-PDO increased as well. These results showed the highest productivity in Lactobacillus species. In addition, hurdle to 1,3-PDO production in this strain were identified via analysis of the half-maximal inhibitory concentration for growth (IC50) of numerous substrates and metabolites. CONCLUSIONS: We used CSL as a low-cost nitrogen source to replace beef extract for 1,3-PDO production in L. reuteri CH53. These cells efficiently utilized crude glycerol and CSL to produce 1,3-PDO. This strain has great promise for the production of 1,3-PDO because it is generally recognized as safe (GRAS) and non-pathogenic. Also, this strain has high productivity and high conversion yield.


Assuntos
Limosilactobacillus reuteri/metabolismo , Propilenoglicóis/metabolismo , Fermentação , Glicerol/metabolismo , Xarope de Milho Rico em Frutose/metabolismo , Microbiologia Industrial/métodos
11.
Bioprocess Biosyst Eng ; 43(1): 33-43, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31549308

RESUMO

In this study, to produce adipic acid, mutant strains of Candida tropicalis KCTC 7212 deficient of AOX genes encoding acyl-CoA oxidases which are important in the ß-oxidation pathway were constructed. Production of adipic acid in the mutants from the most favorable substrate C12 methyl laurate was significantly increased. The highest level of production of adipic acid was obtained in the C. tropicalis ΔAOX4::AOX5 mutant of 339.8 mg L-1 which was about 5.4-fold higher level compared to the parent strain. The C. tropicalis ΔAOX4::AOX5 mutant was subjected to fed-batch fermentation at optimized conditions of agitation rate of 1000 rpm, pH 5.0 and methyl laurate of 3% (w/v), giving the maximum level of adipic acid of 12.1 g L-1 and production rate of 0.1 g L-1 h-1.


Assuntos
Adipatos/metabolismo , Candida tropicalis/genética , Candida tropicalis/metabolismo , Proteínas Fúngicas , Engenharia Metabólica , Mutação , Palmitoil-CoA Hidrolase , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Palmitoil-CoA Hidrolase/genética , Palmitoil-CoA Hidrolase/metabolismo
12.
Sensors (Basel) ; 20(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371295

RESUMO

This study describe the characteristics of hemiplegic stroke gait with principal component analysis (PCA) of trunk movement (TM) and gait event (GE) parameters by the inertial measurement unit (IMU) sensors: (1) Background: This process can determine dominant variables through multivariate examination to identify the affected, unaffected, and healthy lower-limb sides; (2) Methods: The study monitored forty patients with stroke and twenty-eight healthy individuals comprising the control group for comparison. The IMU sensors were attached to each subject while performing a 6 m walking test. Sixteen variables extracted from the measured data were divided into 7 GE and 9 TM variables explaining pelvis tilt, oblique, and rotation. (3) Results: The tilt range variables of the trunk movement on the affected and unaffected sides were lower than those of the healthy side; this showed between-group differences in various GE variables. For the healthy and affected sides, 80% of variances were explained with 2 or 3 PCs involving only a few dominant variables; and (4) Conclusions: The difference between each side leg should be considered during the development of a diagnosis method. This research can be utilized to develop functional assessment tools for personalized treatment and to design appropriate training protocols.


Assuntos
Análise da Marcha , Transtornos Neurológicos da Marcha/diagnóstico , Hemiplegia/diagnóstico , Monitorização Fisiológica/instrumentação , Acidente Vascular Cerebral , Tronco , Idoso , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pelve , Análise de Componente Principal , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico
13.
Int J Syst Evol Microbiol ; 69(11): 3399-3404, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31380735

RESUMO

A white-coloured, Gram-stain-negative, aerobic, rod-shaped bacterium (designated strain SY21T) was isolated from waste-activated sludge. Optimal growth occurred at 28 °C and pH 7.0. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain SY21T exhibited 16S rRNA gene sequence similarities of 95.5-98.0 % to Thermomonas species and clustered with the type species of the genus Thermomonas. In strain SY21T, the predominant respiratory quinone was ubiquinone Q-8, and the cellular fatty acids consisted mainly of iso-C15 : 0, C16 : 0, iso-C11 : 0 3-OH, summed feature 3 and summed feature 9. The major polar lipids were phosphatidylcholine, phosphatidylglycerol and phosphatidylethanolamine. The genomic DNA G+C content was determined to be 67.9 mol% and the DNA-DNA relatedness between strain SY21T and the closest phylogenetically related strain, Thermomonas carbonis KCTC 42013T, was 35.0±0.1 %. Based on the distinct phenotypic, chemotaxonomic and phylogenetic properties, strain SY21T represents a novel species of the genus Thermomonas, for which the name Thermomonas aquatica sp. nov. is proposed. The type strain is SY21T (=KCTC 62191T=NBRC 113114T).


Assuntos
Filogenia , Esgotos/microbiologia , Águas Residuárias/microbiologia , Xanthomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Ubiquinona/química , Xanthomonadaceae/isolamento & purificação
14.
Int J Syst Evol Microbiol ; 68(5): 1800-1805, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29624160

RESUMO

The translucent white-coloured, Gram-stain-negative, aerobic, non-motile, fusiform-shaped bacterium (designated strain SY72T) was isolated from waste-activated sludge. Optimal growth occurred at 30-37 °C and pH 6.0-7.0. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that the novel isolate belonged to the family Rhodobacteraceae of the class Alphaproteobacteria. Strain SY72T is closely related to Tabrizicola aquatica KCTC 23724T (97.8 % 16S rRNA gene sequence similarity) and Pseudorhodobacter aquaticus DC2N1-10T (96.4 %), respectively. DNA-DNA relatedness between strain SY72T and the closest phylogenetically related strain, Tabrizicola aquatica KCTC 23724T, was 18.0±0.7 %. In strain SY72T, the predominant respiratory quinone was ubiquinone Q-10, and the cellular fatty acids consisted mainly of C18 : 1ω7c and C18 : 1ω7c-11 methyl. The major polar lipids were phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. Photoautotrophic and photoheterotrophic growth did not occur in strain SY72T. Furthermore, strain SY72T did not produce photosynthetic pigments or contain the photosynthetic genes pufL and pufM, by which it differed from the phototrophic species of the family Rhodobacteraceae. On the basis of distinct phenotypic and phylogenetic properties, strain SY72T represents a novel species of the genus Tabrizicola, for which the name Tabrizicola fusiformis sp. nov. is proposed. The type strain is SY72T (=KCTC 62105T=NBRC 113021T).


Assuntos
Filogenia , Rhodobacteraceae/classificação , Águas Residuárias , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , República da Coreia , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA , Ubiquinona/química
15.
Microb Cell Fact ; 17(1): 92, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29907119

RESUMO

BACKGROUND: 1,3-Propanediol (1,3-PDO) is important building blocks for the bio-based chemical industry, Klebsiella pneumoniae can be an attractive candidate for their production. However, 1,3-PDO production is high but productivity is generally low by K. pneumoniae. In this study, repeated fed-batch cultivation by a lactate and 2,3-butanediol (2,3-BDO) deficient mutant of K. pneumoniae were investigated for efficient 1,3-PDO production from industrial by-products such as crude glycerol. RESULTS: First, optimal conditions for repeated fed-batch fermentation of a ΔldhA mutant defective for lactate formation due to deletion of the lactate dehydrogenase gene (ldhA) were determined. Maximal 1,3-PDO production level and productivity obtained by repeated fed-batch fermentation under optimized conditions were 81.1 g/L and 3.38 g/L/h, respectively, and these values were successfully maintained for five cycles of fermentation without any loss of fermentation capacity. This results were much higher than that of the normal fed-batch fermentation. The levels of 2,3-BDO, which is a major by-product, reaching up to ~ 50% of the level of 1,3-PDO, were reduced using a mutant strain [Δ(ldhA als)] containing an additional mutation in the biosynthetic pathway of 2,3-BDO (deletion of the acetolactate synthase gene). The levels of 2,3-BDO were reduced to about 20% of 1,3-PDO levels by repeated fed-batch fermentation of Δ(ldhA als), although maximal 1,3-PDO production and productivity also decreased owing to a defect in the growth of the 2,3-BDO-defective mutant strain. CONCLUSION: This repeated fed-batch fermentation may be useful for reducing the cost of 1,3-PDO production and may be promising industrialization prospect for the 1,3-PDO production.


Assuntos
Vias Biossintéticas/imunologia , Butileno Glicóis/metabolismo , Glicerol/metabolismo , Klebsiella pneumoniae/patogenicidade , Ácido Láctico/metabolismo , Propilenoglicóis/metabolismo , Fermentação
16.
Bioprocess Biosyst Eng ; 41(9): 1355-1370, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29948212

RESUMO

Results to date suggest that microalgal Thraustochytrids family strains can be used to produce high-functional omega-3 rich oil (~ 30-70% of dry cell weight) and carotenoid-based antioxidant pigments simultaneously with value-added bioactive potential. In the present study, we describe the isolation and characterization of a new Thraustochytrid Schizochytrium sp. from the west coastal area of Korea. This newly isolated Thraustochytrid, identified as Schizochytrium sp. through 18S rRNA analysis and named SH104, simultaneously produces high levels of DHA and carotenoid-based antioxidant pigments. An improved Schizochytrium mutant, named SHG104, was obtained from the original host strain by γ-irradiation-induced mutagenesis. Under combined temperature-shift cultivation conditions employing white-light LEDs (light-emitting diodes), Schizochytrium sp. SHG104 yielded 10.8 g L-1 of biomass comprising 45.8% total lipids (32.1% DHA) and 4.6 mg L-1 of astaxanthin. In addition to DHA, the main fatty acids produced by Schizochytrium sp. SHG104 were palmitic acid and a trace of other long-chain fatty acids. The carotenoid profile of SH104 and SHG104 was ß-carotene, astaxanthin, canthaxanthin, pheonicoxanthin and echinenone, which analyzed by HPLC and LC/APCI-MS. Furthermore, genomic analysis of Schizochytrium and Aurantiochytrium microalgae confirmed that the presence of carotenogenesis pathway enzymes and genes including geranylgeranyl diphosphate, phytoene synthase, lycopene cyclase, and cytochrome P450 hydroxylase that necessary for the production of antioxidants via a complete biosynthetic KEGG synthesis pathway. This newly isolated Schizochytrium microalga potentially have wide application as a source of antioxidants for astaxanthin-containing pigments, commercial omega-3 lipids and feed additives, such as nutritional supplements for aquaculture.


Assuntos
Carotenoides/biossíntese , Ácidos Docosa-Hexaenoicos/metabolismo , Estramenópilas/crescimento & desenvolvimento , Raios gama , Mutagênese , Estramenópilas/genética , Estramenópilas/isolamento & purificação
17.
J Ind Microbiol Biotechnol ; 44(7): 1107-1113, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28315963

RESUMO

A Bacillus sp. strain named BRC1 is capable of producing 2,3-butanediol (2,3-BD) using hydrolysates of the Jerusalem artichoke tuber (JAT), a rich source of the fructose polymer inulin. To enhance 2,3-BD production, we undertook an extensive analysis of the Bacillus sp. BRC1 genome, identifying a putative gene (sacC) encoding a fructan hydrolysis enzyme and characterizing the activity of the resulting recombinant protein expressed in and purified from Escherichia coli. Introduction of the sacC gene into Bacillus sp. BRC1 using an expression vector increased enzymatic activity more than twofold. Consistent with this increased enzyme expression, 2,3-BD production from JAT was also increased from 3.98 to 8.10 g L-1. Fed-batch fermentation of the recombinant strain produced a maximal level of 2,3-BD production of 28.6 g L-1, showing a high theoretical yield of 92.3%.


Assuntos
Bacillus/genética , Butileno Glicóis/metabolismo , Glicosídeo Hidrolases/metabolismo , Helianthus/química , Extratos Vegetais/química , Tubérculos/química , Sequência de Aminoácidos , Bacillus/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Cultura Celular por Lotes , Clonagem Molecular , Escherichia coli/genética , Genes Bacterianos , Glicosídeo Hidrolases/genética , Inulina/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Proteínas Recombinantes
18.
J Neurosci Res ; 94(2): 170-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26568405

RESUMO

Methamphetamine is a potent psychostimulant drug of abuse that increases release and blocks reuptake of dopamine, producing intense euphoria, factors that may contribute to its widespread abuse. It also produces severe neurotoxicity resulting from oxidative stress, DNA damage, blood-brain barrier disruption, microgliosis, and mitochondrial dysfunction. Intracerebral hemorrhagic and ischemic stroke have been reported after intravenous and oral abuse of methamphetamine. Several studies have shown that methamphetamine causes vasoconstriction of vessels. This study investigates the effect of methamphetamine on endothelin-1 (ET-1) release in mouse brain endothelial cells by ELISA. ET-1 transcription as well as endothelial nitric oxide synthase (eNOS) activation and transcription were measured following methamphetamine treatment. We also examine the effect of methamphetamine on isolated cerebral arteriolar vessels from C57BL/6 mice. Penetrating middle cerebral arterioles were cannulated at both ends with a micropipette system. Methamphetamine was applied extraluminally, and the vascular response was investigated. Methamphetamine treatment of mouse brain endothelial cells resulted in ET-1 release and a transient increase in ET-1 message. The activity and transcription of eNOS were only slightly enhanced after 24 hr of treatment with methamphetamine. In addition, methamphetamine caused significant vasoconstriction of isolated mouse intracerebral arterioles. The vasoconstrictive effect of methamphetamine was attenuated by coapplication of the endothelin receptor antagonist PD145065. These findings suggest that vasoconstriction induced by methamphetamine is mediated through the endothelin receptor and may involve an endothelin-dependent pathway.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Endotelina-1/metabolismo , Endotélio/efeitos dos fármacos , Metanfetamina/farmacologia , Análise de Variância , Animais , Artérias/efeitos dos fármacos , Encéfalo/citologia , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Endotelina-1/antagonistas & inibidores , Endotelina-1/genética , Ensaio de Imunoadsorção Enzimática , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/metabolismo , Oligopeptídeos/farmacologia , RNA Mensageiro/metabolismo , Fatores de Tempo , Vasoconstrição/efeitos dos fármacos
19.
Appl Microbiol Biotechnol ; 100(24): 10453-10461, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27412460

RESUMO

Expressing proteins with fusion partners improves yield and simplifies the purification process. We developed a novel fusion partner to improve the secretion of heterologous proteins that are otherwise poorly excreted in yeast. The VOA1 (YGR106C) gene of Saccharomyces cerevisiae encodes a subunit of vacuolar ATPase. We found that C-terminally truncated Voa1p was highly secreted into the culture medium, even when fused with rarely secreted heterologous proteins such as human interleukin-2 (hIL-2). Deletion mapping of C-terminally truncated Voa1p, identified a hydrophilic 28-amino acid peptide (HL peptide) that was responsible for the enhanced secretion of target protein. A purification tag and a protease cleavage site were added to use HL peptide as a multi-purpose fusion partner. The utility of this system was tested via the expression and purification of various heterologous proteins. In many cases, the yield of target proteins fused with the peptide was significantly increased, and fusion proteins could be directly purified with affinity chromatography. The fusion partner was removed by in vitro processing, and intact proteins were purified by re-application of samples to affinity chromatography.


Assuntos
Engenharia de Proteínas/métodos , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Interleucina-2/genética , Interleucina-2/metabolismo , Proteínas Recombinantes de Fusão/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , ATPases Vacuolares Próton-Translocadoras/genética
20.
J Phys Ther Sci ; 28(8): 2245-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27630406

RESUMO

[Purpose] Proper pedaling posture can improve muscle strength and cardiopulmonary function. To investigate proper pedaling posture for the elderly, this study compared the pedaling efficiency of the elderly with that of the young by using an index of effectiveness (IE) and kinematic results. [Subjects and Methods] Eight adults in their twenties and eight in their seventies participated in 3-min, 40 rpm cycle pedaling tests, with the same load and cadence. The joint angle, range of motion (ROM), and IE were compared by measuring 3-dimensional motion and 3-axis pedal-reaction force during 4 pedaling phases (Phase 1: 330-30°, Phase 2: 30-150°, Phase 3: 150-210°, and Phase 4: 210-330°). [Results] The knee and ankle ROM, maximum knee extension, and maximum ankle dorsiflexion in the elderly were significantly decreased compared with those in the young. Moreover, there were significant differences in IE for the total phase, Phase 1, and Phase 4 between the elderly and young. IE of the young was greater than that of the elderly, except in Phase 3. [Conclusion] Joint movement in the elderly during pedaling was limited. This study provides information that will facilitate the proposal of an efficient pedaling method for the elderly.

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