Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Molecules ; 26(5)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803168

RESUMO

Light is a key factor that affects phytochemical synthesis and accumulation in plants. Due to limitations of the environment or cultivated land, there is an urgent need to develop indoor cultivation systems to obtain higher yields with increased phytochemical concentrations using convenient light sources. Light-emitting diodes (LEDs) have several advantages, including consumption of lesser power, longer half-life, higher efficacy, and wider variation in the spectral wavelength than traditional light sources; therefore, these devices are preferred for in vitro culture and indoor plant growth. Moreover, LED irradiation of seedlings enhances plant biomass, nutrient and secondary metabolite levels, and antioxidant properties. Specifically, red and blue LED irradiation exerts strong effects on photosynthesis, stomatal functioning, phototropism, photomorphogenesis, and photosynthetic pigment levels. Additionally, ex vitro plantlet development and acclimatization can be enhanced by regulating the spectral properties of LEDs. Applying an appropriate LED spectral wavelength significantly increases antioxidant enzyme activity in plants, thereby enhancing the cell defense system and providing protection from oxidative damage. Since different plant species respond differently to lighting in the cultivation environment, it is necessary to evaluate specific wavebands before large-scale LED application for controlled in vitro plant growth. This review focuses on the most recent advances and applications of LEDs for in vitro culture organogenesis. The mechanisms underlying the production of different phytochemicals, including phenolics, flavonoids, carotenoids, anthocyanins, and antioxidant enzymes, have also been discussed.


Assuntos
Agricultura/métodos , Fotossíntese/efeitos da radiação , Compostos Fitoquímicos/efeitos da radiação , Antocianinas , Antioxidantes , Biomassa , Carotenoides , Produtos Agrícolas/crescimento & desenvolvimento , Flavonoides , Luminescência , Valor Nutritivo/fisiologia , Fenóis , Desenvolvimento Vegetal/fisiologia , Plantas Medicinais
2.
J Ethnopharmacol ; 202: 78-84, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28286104

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Selaginella tamariscina (P.Beauv.) Spring is a traditional medicinal plant used to treat various human diseases, including cancer, in Asia. The detailed molecular mechanism underlying the anti-cancer effects of this plant and the anti-cancer action of the combinatorial treatment of S. tamariscina and doxorubicin have not yet been investigated. AIM OF THE STUDY: We evaluated the inhibitory activity of S. tamariscina extract (STE) and its major compound, amentoflavone, on human aldo-keto reductase family 1B10 (AKR1B10), which is a detoxification enzyme involved in drug resistance, to evaluate their anti-cancer effects and their potential as adjuvant agents for doxorubicin cancer chemotherapy. MATERIALS AND METHODS: We tested the AKR1B10 inhibitory activity of STE and amentoflavone via an in vitro biochemical assay using recombinant human AKR1B10. We tested the anti-proliferative activity in A549, NCI-H460, SKOV-3, and MCF-7 human cancer cells, which contain different expression levels of AKR1B10, and determined the combination index to evaluate whether the addition of STE and amentoflavone is synergistic or antagonistic to the anti-cancer action of doxorubicin. We finally evaluated the in vivo anti-tumor effects of STE in a nude mouse xenograft model of A549 cells. RESULTS: STE and amentoflavone potently inhibited human AKR1B10 and synergistically increased the doxorubicin anti-proliferative effect in A549 and NCI-H460 human lung cancer cells that express a high level of AKR1B10 mRNA and protein. STE also significantly inhibited A549 tumor growth in animal experiments. CONCLUSION: Our results suggest that STE and amentoflavone could be potential anti-cancer agents that target AKR1B10 and might be candidate adjuvant agents to boost the anti-cancer effect of doxorubicin.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Biflavonoides/farmacologia , Extratos Vegetais/farmacologia , Selaginellaceae/química , Células A549 , Adjuvantes Farmacêuticos , Aldo-Ceto Redutases , Animais , Antibióticos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/uso terapêutico , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Sci Rep ; 6: 33438, 2016 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-27633501

RESUMO

A sorbitol dehydrogenase (GoSLDH) from Gluconobacter oxydans G624 (G. oxydans G624) was expressed in Escherichia coli BL21(DE3)-CodonPlus RIL. The complete 1455-bp codon-optimized gene was amplified, expressed, and thoroughly characterized for the first time. GoSLDH exhibited Km and kcat values of 38.9 mM and 3820 s(-1) toward L-sorbitol, respectively. The enzyme exhibited high preference for NADP(+) (vs. only 2.5% relative activity with NAD(+)). GoSLDH sequencing, structure analyses, and biochemical studies, suggested that it belongs to the NADP(+)-dependent polyol-specific long-chain sorbitol dehydrogenase family. GoSLDH is the first fully characterized SLDH to date, and it is distinguished from other L-sorbose-producing enzymes by its high activity and substrate specificity. Isothermal titration calorimetry showed that the protein binds more strongly to D-sorbitol than other L-sorbose-producing enzymes, and substrate docking analysis confirmed a higher turnover rate. The high oxidation potential of GoSLDH for D-sorbitol was confirmed by cyclovoltametric analysis. Further, stability of GoSLDH significantly improved (up to 13.6-fold) after cross-linking of immobilized enzyme on silica nanoparticles and retained 62.8% residual activity after 10 cycles of reuse. Therefore, immobilized GoSLDH may be useful for L-sorbose production from D-sorbitol.


Assuntos
Enzimas Imobilizadas/metabolismo , Gluconobacter oxydans/enzimologia , L-Iditol 2-Desidrogenase/metabolismo , Calorimetria , Técnicas Eletroquímicas , Estabilidade Enzimática/efeitos dos fármacos , Íons , Cinética , L-Iditol 2-Desidrogenase/isolamento & purificação , Metais/farmacologia , Simulação de Acoplamento Molecular , NADP/metabolismo , Proteínas Recombinantes/metabolismo , Sorbitol/metabolismo , Sorbose/biossíntese , Especificidade por Substrato/efeitos dos fármacos , Termodinâmica
4.
PLoS One ; 10(7): e0131585, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26171785

RESUMO

The BaM6PI gene encoding a mannose-6-phosphate isomerase (M6PI, EC 5.3.1.8) was cloned from Bacillus amyloliquefaciens DSM7 and overexpressed in Escherichia coli. The enzyme activity of BaM6PI was optimal at pH and temperature of 7.5 and 70°C, respectively, with a kcat/Km of 13,900 s-1 mM-1 for mannose-6-phosphate (M6P). The purified BaM6PI demonstrated the highest catalytic efficiency of all characterized M6PIs. Although M6PIs have been characterized from several other sources, BaM6PI is distinguished from other M6PIs by its wide pH range and high catalytic efficiency for M6P. The binding orientation of the substrate M6P in the active site of BaM6PI shed light on the molecular basis of its unusually high activity. BaM6PI showed 97% substrate conversion from M6P to fructose-6-phosphate demonstrating the potential for using BaM6PI in industrial applications.


Assuntos
Bacillus/enzimologia , Frutosefosfatos/biossíntese , Manose-6-Fosfato Isomerase/genética , Manose-6-Fosfato Isomerase/metabolismo , Sequência de Aminoácidos , Bacillus/genética , Clonagem Molecular , Cristalografia por Raios X , Estabilidade Enzimática , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Cinética , Manose-6-Fosfato Isomerase/química , Metais/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Peso Molecular , Estrutura Quaternária de Proteína , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Temperatura
5.
Sci Rep ; 5: 10151, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25955763

RESUMO

Piezoelectric materials capable of converting between mechanical and electrical energy have a great range of potential applications in micro- and nano-scale smart devices; however, their performance tends to be greatly degraded when reduced to a thin film due to the large clamping force by the substrate and surrounding materials. Herein, we report an effective method for synthesizing isolated piezoelectric nano-materials as means to relax the clamping force and recover original piezoelectric properties of the materials. Using this, environmentally friendly single-crystalline NaxK1-xNbO3 (NKN) piezoelectric nano-rod arrays were successfully synthesized by conventional pulsed-laser deposition and demonstrated to have a remarkably enhanced piezoelectric performance. The shape of the nano-structure was also found to be easily manipulated by varying the energy conditions of the physical vapor. We anticipate that this work will provide a way to produce piezoelectric micro- and nano-devices suitable for practical application, and in doing so, open a new path for the development of complex metal-oxide nano-structures.

6.
Sci Rep ; 5: 9309, 2015 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-25791299

RESUMO

Recently, piezoelectric and triboelectric energy harvesting devices have been developed to convert mechanical energy into electrical energy. Especially, it is well known that triboelectric nanogenerators have a simple structure and a high output voltage. However, whereas nanostructures improve the output of triboelectric generators, its fabrication process is still complicated and unfavorable in term of the large scale and long-time durability of the device. Here, we demonstrate a hybrid generator which does not use nanostructure but generates much higher output power by a small mechanical force and integrates piezoelectric generator into triboelectric generator, derived from the simultaneous use of piezoelectric and triboelectric mechanisms in one press-and-release cycle. This hybrid generator combines high piezoelectric output current and triboelectric output voltage, which produces peak output voltage of ~370 V, current density of ~12 µA · cm(-2), and average power density of ~4.44 mW · cm(-2). The output power successfully lit up 600 LED bulbs by the application of a 0.2 N mechanical force and it charged a 10 µF capacitor to 10 V in 25 s. Beyond energy harvesting, this work will provide new opportunities for developing a small, built-in power source in self-powered electronics such as mobile electronics.

7.
J Nanosci Nanotechnol ; 15(11): 8907-11, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26726616

RESUMO

Piezoelectric power generation using Pb(Zr,Ti)O3(PZT) nanowires grown on Nb-doped SrTiO3(nb:STO) substrate has been demonstrated. The epitaxial PZT nanowires prepared by a hydrothermal method, with a diameter and length of approximately 300 nm and 7 µm, respecively, were vertically aligned on the substrate. An embossed Au top electrode was applied to maximize the effective power generation area for non-uniform PZT nanowires. The PZT nanogenerator produced output power density of 0.56 µW/cm2 with a voltage of 0.9 V and current of 75 nA. This research suggests that the morphology control of top electrode can be useful to improve the efficiency of piezoelectric power generation.

8.
PLoS One ; 8(8): e72902, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24015281

RESUMO

D-Galactose-6-phosphate isomerase from Lactobacillus rhamnosus (LacAB; EC 5.3.1.26), which is encoded by the tagatose-6-phosphate pathway gene cluster (lacABCD), catalyzes the isomerization of D-galactose-6-phosphate to D-tagatose-6-phosphate during lactose catabolism and is used to produce rare sugars as low-calorie natural sweeteners. The crystal structures of LacAB and its complex with D-tagatose-6-phosphate revealed that LacAB is a homotetramer of LacA and LacB subunits, with a structure similar to that of ribose-5-phosphate isomerase (Rpi). Structurally, LacAB belongs to the RpiB/LacAB superfamily, having a Rossmann-like αßα sandwich fold as has been identified in pentose phosphate isomerase and hexose phosphate isomerase. In contrast to other family members, the LacB subunit also has a unique α7 helix in its C-terminus. One active site is distinctly located at the interface between LacA and LacB, whereas two active sites are present in RpiB. In the structure of the product complex, the phosphate group of D-tagatose-6-phosphate is bound to three arginine residues, including Arg-39, producing a different substrate orientation than that in RpiB, where the substrate binds at Asp-43. Due to the proximity of the Arg-134 residue and backbone Cα of the α6 helix in LacA to the last Asp-172 residue of LacB with a hydrogen bond, a six-carbon sugar-phosphate can bind in the larger pocket of LacAB, compared with RpiB. His-96 in the active site is important for ring opening and substrate orientation, and Cys-65 is essential for the isomerization activity of the enzyme. Two rare sugar substrates, D-psicose and D-ribulose, show optimal binding in the LacAB-substrate complex. These findings were supported by the results of LacA activity assays.


Assuntos
Aldose-Cetose Isomerases/química , Hexosefosfatos/química , Lacticaseibacillus rhamnosus/enzimologia , Dobramento de Proteína , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/metabolismo , Domínio Catalítico/fisiologia , Cristalografia por Raios X , Frutose/química , Frutose/genética , Frutose/metabolismo , Hexosefosfatos/genética , Hexosefosfatos/metabolismo , Lacticaseibacillus rhamnosus/genética , Pentoses/química , Pentoses/genética , Pentoses/metabolismo , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Relação Estrutura-Atividade
9.
Environ Toxicol Pharmacol ; 36(1): 19-29, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23542413

RESUMO

Antimycin A (AMA) damages the mitochondria through inhibition of mitochondrial electron transport. In this study, exposure of L6 rat skeletal muscle cells to AMA induced a decrease in ATP content, followed by a decrease in mitochondrial membrane potential, leading to apoptosis. We evaluated the protective effects of water and ethanol extracts of Nelumbo nucifera seeds on L6 cells with AMA-induced oxidative stress. We found that the extracts reduced cellular apoptosis; preserved the mitochondrial membrane potential; protected mitochondrial ATP production; inhibited p53, Bax, and caspase 3 activities; and induced Bcl-2 production. Our results suggested that AMA induced apoptosis in L6 cells via impairment of mitochondrial function. N. nucifera extracts protected the cells from this mitochondria-mediated cell death.


Assuntos
Antimicina A/toxicidade , Mitocôndrias/efeitos dos fármacos , Nelumbo , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/fisiologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Sementes
10.
Korean J Anesthesiol ; 64(1): 29-33, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23372883

RESUMO

BACKGROUND: To analyze how lidocaine 40 mg mixed prevents injection pain of propofol affects the onset time of rocuronium, tracheal intubating conditions and intubation related hemodynamic changes. METHODS: This study consisted of 70 patients with an American Society of Anesthesiologists (ASA) physical status class 1 or 2 for general anesthesia. All the patients were randomly allocated into two groups: propofol 2 mg/kg plus normal saline 2 ml (Group C) and propofol 2 mg/kg plus 2% lidocaine 40 mg (Group L). Each group was administrated intravenously during induction and the patient was intubated 1 minute after an injection of 0.6 mg/kg of rocuronium. The time at disappearance of the first twitch and intubation scores were recorded. Also, blood pressure and heart rate were measured at the baseline, after intravenous injection of propofol, before intubation, and at 0, 1, 2, 3 and 5 minutes after intubation. RESULTS: There were no significant differences between group C and L (P > 0.05). CONCLUSIONS: 40 mg of lidocaine mixed with propofol to prevent injection pain did not affect the onset time of rocuronium, intubating conditions and intubation related hemodynamic changes.

11.
Artigo em Inglês | MEDLINE | ID: mdl-22969827

RESUMO

Antimycin A (AMA) damages mitochondria by inhibiting mitochondrial electron transport and can produce reactive oxygen species (ROS). ROS formation, aging, and reduction of mitochondrial biogenesis contribute to mitochondrial dysfunction. The present study sought to investigate extracts of Scutellaria baicalensis and its flavonoids (baicalin, baicalein, and wogonin), whether they could protect mitochondria against oxidative damage. The viability of L6 cells treated with AMA increased in the presence of flavonoids and extracts of S. baicalensis. ATP production decreased in the AMA treated group, but increased by 50% in cells treated with flavonoids (except wogonin) and extracts of S. baicalensis compared to AMA-treated group. AMA treatment caused a significant reduction (depolarized) in mitochondrial membrane potential (MMP), whereas flavonoid treatment induced a significant increase in MMP. Mitochondrial superoxide levels increased in AMA treated cells, whereas its levels decreased when cells were treated with flavonoids or extracts of S. baicalensis. L6 cells treated with flavonoids and extracts of S. baicalensis increased their levels of protein expression compared with AMA-treated cells, especially water extracts performed the highest levels of protein expression. These results suggest that the S. baicalensis extracts and flavonoids protect against AMA-induced mitochondrial dysfunction by increasing ATP production, upregulating MMP, and enhancing mitochondrial function.

12.
J Asian Nat Prod Res ; 14(4): 301-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22375866

RESUMO

Two new compounds stigmast-5-en-3ß-ol-3-O-ß-D-(2'-n-triacontanoyl) glucopyranoside (1) and 19,21-dimethyl triacont-17,22,24,26,28-pentaene-1-oic acid (2), along with the three known compounds n-tetracosanyl octadec-9-enoate (3), ß-sitosterol, and ß-sitosterol-3-O-ß-D-glucoside, have been isolated from the methanol extract of Lycium chinense fruits. The structures of these phytoconstituents have been established on the basis of spectral data analysis and chemical reactions.


Assuntos
Ácidos Graxos Insaturados/isolamento & purificação , Glucosídeos/isolamento & purificação , Lycium/química , Ácidos Graxos Insaturados/química , Frutas/química , Glucosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , República da Coreia , Estigmasterol/análogos & derivados
13.
Immunopharmacol Immunotoxicol ; 34(3): 499-503, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22208224

RESUMO

The seeds of the Coriandrum sativum were extracted and the essential oil composition and immunotoxicity effects were studied. The analysis of the essential oil was conducted by gas chromatography-mass spectroscopy, which revealed 33 components, representing 99.99% of the total oil from the seeds of coriander. The major components are linalool (55.09%), α-pinene (7.49%), 2,6-Octadien-1-ol, 3,7-dimethyl-, acetate, (E)- (5.70%), geraniol (4.83%), 3-Cyclohexene-1-methanol, α,α,4-trimethyl- (4.72%), hexadecanoic acid (2.65%), tetradecanoic acid (2.49%), 2-α-pinene (2.39%), citronellyl acetate (1.77%), and undecanal (1.29%). The seed oil had significant toxic effects against the larvae of Aedes aegypti with an LC(50) value of 21.55 ppm and LC(90) value of 38.79 ppm. The above data indicate that the major components in the essential oil of coriander play an important role as immunotoxicity on the A. aegypti.


Assuntos
Anopheles/imunologia , Coriandrum/química , Citotoxinas/farmacologia , Óleos Voláteis/farmacologia , Animais , Citotoxinas/química , Óleos Voláteis/química
14.
PLoS One ; 6(7): e22443, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21799856

RESUMO

Pathogenic bacteria synthesize and secrete toxic low molecular weight compounds as virulence factors. These microbial toxins play essential roles in the pathogenicity of bacteria in various hosts, and are emerging as targets for antivirulence strategies. Toxoflavin, a phytotoxin produced by Burkholderia glumae BGR1, has been known to be the key factor in rice grain rot and wilt in many field crops. Recently, toxoflavin-degrading enzyme (TxDE) was identified from Paenibacillus polymyxa JH2, thereby providing a possible antivirulence strategy for toxoflavin-mediated plant diseases. Here, we report the crystal structure of TxDE in the substrate-free form and in complex with toxoflavin, along with the results of a functional analysis. The overall structure of TxDE is similar to those of the vicinal oxygen chelate superfamily of metalloenzymes, despite the lack of apparent sequence identity. The active site is located at the end of the hydrophobic channel, 9 Å in length, and contains a Mn(II) ion interacting with one histidine residue, two glutamate residues, and three water molecules in an octahedral coordination. In the complex, toxoflavin binds in the hydrophobic active site, specifically the Mn(II)-coordination shell by replacing a ligating water molecule. A functional analysis indicated that TxDE catalyzes the degradation of toxoflavin in a manner dependent on oxygen, Mn(II), and the reducing agent dithiothreitol. These results provide the structural features of TxDE and the early events in catalysis.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Paenibacillus/enzimologia , Pirimidinonas/metabolismo , Toxinas Biológicas/metabolismo , Triazinas/metabolismo , Sequência de Aminoácidos , Biocatálise , Domínio Catalítico , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Pirimidinonas/química , Toxinas Biológicas/química , Triazinas/química
15.
Biotechnol Prog ; 27(4): 937-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21674816

RESUMO

The leaves of Catharanthus roseus (L.) G. Don. are a valuable source of the terpenoid indole alkaloid (TIA) anticancer drugs, vinblastine and vincristine. In particular, the precursor molecules vindoline and catharanthine are harvested from leaves and used for the semisynthetic production of vinblastine and vincristine. Because of this application, catharanthine and vindoline can be used to screen for high-yielding TIA cultivars. In this study, we compared the TIA concentrations in the leaves of 64 different cultivars of C. roseus in the soil experiments. The highest concentration of serpentine was found in Cooler Rose Hot (461±46 µg/g DW). Concentrations of vindoline (2082±113 µg/g DW) and catharanthine (2903±384 µg/g DW) were highest in Pacifica Peach. To eliminate the abiotic and biotic effects of the soils on the plant growth, sterile agar experiments were performed to investigate the TIA concentrations and mRNA transcript levels of selected TIA pathway genes. Six cultivars were investigated (two each of the high level, mid level, and low level producers of TIAs).


Assuntos
Catharanthus/metabolismo , Alcaloides de Triptamina e Secologanina/metabolismo , Vimblastina/análogos & derivados , Alcaloides de Vinca/metabolismo , Catharanthus/genética , Cromatografia Líquida de Alta Pressão , Reação em Cadeia da Polimerase , Vimblastina/metabolismo
16.
Yonsei Med J ; 51(4): 585-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20499427

RESUMO

PURPOSE: The present visual and electromyographic study was designed to evaluate muscle fasciculations caused by succinylcholine in adults pretreated with either remifentanil 1.5 microg/kg or saline. MATERIALS AND METHODS: The effect of remifentanil on succinylcholine-induced muscle fasciculations was studied using a double-blind method in 40 adults. After i.v. pretreatment with either remifentanil 1.5 microg/kg (remifentanil group, n = 20) or an equivalent volume of i.v. saline (saline group, n = 20), patients were anaesthetized with a 2.0 mg/kg of i.v. propofol followed by i.v. succinylcholine 1.0 mg/kg. Intensity and duration of muscle fasciculation following i.v. succinylcholine administration were recorded. Electromyography (EMG) was used to quantify the extent of muscle fasciculation following i.v. succinylcholine injection. Myalgia was evaluated 24 hours after induction time. Serum potassium levels were measured five minutes after i.v. succinylcholine administration and creatine kinase (CK) levels 24 hours after induction time. RESULTS: Compared to saline treated controls, remifentanil decreased the intensity of muscle fasciculations caused by i.v. succinylcholine [fasciculation severity scores (grade 0 to 3) were 2/1/12/5 and 3/13/4/0 (patients numbers) in the saline group and the remifentanil group, respectively, p < 0.001]. The mean (SD) maximum amplitude of muscle action potential (MAP) by EMG was smaller in the remifentanil group [283.0 (74.4) microV] than in the saline group [1480.4 (161.3) microV] (p = 0.003). Postoperative serum CK levels were lower in the remifentanil group (p < 0.001). Postoperative myalgia was not different between the two groups. CONCLUSION: Remifentanil 1.5 microg/kg attenuated intensity of muscle fasciculations by succinylcholine.


Assuntos
Fasciculação/tratamento farmacológico , Piperidinas/uso terapêutico , Succinilcolina/efeitos adversos , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Creatina Quinase/sangue , Método Duplo-Cego , Eletromiografia , Fasciculação/induzido quimicamente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Remifentanil
17.
Ultrasonics ; 49(6-7): 594-8, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19395053

RESUMO

A piezoelectric motor capable of omni-directional movements has been developed to apply for robot joints, eyes, and precision positioning stage. The piezoelectric actuator has a simple structure of a cone type consisting of two piezoelectric ring-typed ceramics with electrodes divided into four segments and stainless steel elastic bodies. Before manufacturing the piezoelectric motor, the admittance characteristics and displacements of the actuator as a function of frequency were simulated. Elliptical motions of the actuator were created at several frequencies between the longitudinal and transverse resonance frequencies. The actual motor with alumina ball exhibited nice performance using a driving circuit with two rotary encoders and a PID controller. The moving element was omni-directionally operated at a driving frequency of 53.8 kHz and an output voltage of 280 V(p-p). The developed motor enables the moving element to move to a desired position with a resolution of 1.2 degrees/pulse, an angular velocity of 4 rad/s, and a thrust force of 200 g.

18.
J Agric Food Chem ; 56(8): 2751-8, 2008 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-18376845

RESUMO

The seeds of 322 Korean soybean varieties were collected from six different cultivated sites in Korea and classified into three groups based on the 100-seed weight as small, medium, and large. Seeds were analyzed for their concentrations of isoflavones and phenolic compounds. The total average isoflavones in soybean cultivated at Iksan (2.840 micromol g(-1)) and phenolic compounds in soybean grown at Yeoncheon (9.216 micromol g(-1)) and Iksan (9.154 micromol g(-1)) were significantly different (p<0.05). In small and medium seeds of soybeans cultivated at Yeoncheon, Yesan, and Milyang high levels of isoflavones were obtained, whereas soybeans grown in Chuncheon showed the lowest isoflavone concentrations. However, isoflavone concentrations in the large seeds of soybean cultivated at Chuncheon showed the highest level. The soybean cultivated at Yeoncheon had high levels of phenolic compounds in small, medium, and large seeds, whereas the soybean grown at Chuncheon had the lowest. On the other hand, the phenolic concentrations of large soybean cultivated at Milyang were the least. At Yeoncheon, Yesan, and Milyang, the total isoflavone and phenolic compounds levels related to their seed size was significantly different (p<0.05), whereas in the soybean of different sizes cultivated at Chuncheon, the relationship to their seed size was not significantly different. The relationships of total isoflavones and phenolic compounds of small and medium soybean seeds were significantly higher than that of large soybean seeds. The hydroxybenzoic acid group in all sizes of seeds cultivated at six sites in Korea was the major phenolic compound, followed by flavonoid and hydroxycinnamic acid. The total isoflavone concentration was positively correlated with acetylglycoside and negatively correlated with malonylglycoside in the small soybean seeds cultivated at Yeoncheon. In medium soybean seeds cultivated at Yeoncheon, a significantly positive correlation was found between acetylglycoside and glycoside, between aglycone and glycoside, and between aglycone and acetylglycoside, whereas a significantly negative correlation was shown between malonylglycoside and glycoside, between acetylglycoside and malonylglycoside, and between aglycone and malonylglycoside. In large soybean seeds cultivated at Chuncheon, significantly positive and negative correlations were similar to those of medium seeds. The results presented here can improve the understanding of the relationships among the concentrations of individual chemical compounds and each chemical compound group and total chemical compounds in soybeans of different seed sizes from different cultivated sites.


Assuntos
Glycine max/química , Isoflavonas/análise , Fenóis/análise , Sementes/química , Cromatografia Líquida de Alta Pressão , Coreia (Geográfico) , Sementes/anatomia & histologia
19.
J Biol Chem ; 282(11): 8414-23, 2007 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-17192265

RESUMO

Inulin fructotransferase (IFTase), a member of glycoside hydrolase family 91, catalyzes depolymerization of beta-2,1-fructans inulin by successively removing the terminal difructosaccharide units as cyclic anhydrides via intramolecular fructosyl transfer. The crystal structures of IFTase and its substrate-bound complex reveal that IFTase is a trimeric enzyme, and each monomer folds into a right-handed parallel beta-helix. Despite variation in the number and conformation of its beta-strands, the IFTase beta-helix has a structure that is largely reminiscent of other beta-helix structures but is unprecedented in that trimerization is a prerequisite for catalytic activity, and the active site is located at the monomer-monomer interface. Results from crystallographic studies and site-directed mutagenesis provide a structural basis for the exolytic-type activity of IFTase and a functional resemblance to inverting-type glycosyltransferases.


Assuntos
Frutose/química , Hexosiltransferases/fisiologia , Sequência de Aminoácidos , Bacillus/enzimologia , Cristalização , Cristalografia por Raios X , Primers do DNA/química , Dimerização , Hexosiltransferases/metabolismo , Modelos Químicos , Conformação Molecular , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Conformação Proteica , Estrutura Secundária de Proteína , Homologia de Sequência de Aminoácidos
20.
Talanta ; 71(4): 1642-51, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19071503

RESUMO

It is important to define a standard method to store basic sensor information, such as the type and the structure of sensors for an electronic tongue system and there is no such method defined in the IEEE 1451.4 transducer electronic data sheet (TEDS) so far. The major challenge is to choose a suitable standard template that can be used with sensors for electronic tongues. However, the standard templates provide an imprecise specification when used with sensing devices for electronic tongues. In this paper, we present definitions of the basic TEDS of IEEE 1451.4 for sensors for an electronic tongue system and propose a new template TEDS for IEEE 1451.4 for potentiometric devices.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...