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1.
BMC Neurol ; 23(1): 324, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700225

RESUMO

BACKGROUND: Stroke survivors have long-term upper limb impairment, which impacts the quality of life (QOL) and social reintegration, but there is lack of effective therapeutic strategies and novel technologies. Customized multi-muscle functional electrical stimulation (FES) based on the muscle synergy of healthy adults and robotic-assisted therapy (RAT) have been proved efficacy respectively. Synergy-based FES combined with RAT can be a novel and more effective therapy for upper limb recovery of stroke survivors from the perspective of synergistic enhancement. However, few studies have examined the effectiveness of combined synergy-based FES and RAT, especially for motor control evaluated by reach-to-grasp (RTG) movements. The main objective of the following research protocol is to evaluate the effectiveness and efficacy, as well as adoptability, of FES-RAT and FES or RAT rehabilitation program for upper limb function improvement after stroke. METHODS: This will be an assessor-blinded randomized controlled trial involving a 12-week intervention and a 6-month follow-up. Stratified randomization will be used to equally and randomly assign 162 stroke patients into the FES + conventional rehabilitation program (CRP) group, RAT + CRP group and FES-RAT + CRP group. Interventions will be provided in 5 sessions per week, with a total of 60 sessions. The primary outcome measurements will include the Fugl-Meyer Assessment and Biomechanical Assessment of RTG movements. The secondary outcome measurements will include quality of life and brain neuroplasticity assessments by MRI. Evaluations will be performed at five time points, including at baseline, 6 weeks and 12 weeks from the start of treatment, and 3 months and 6 months following the end of treatment. A two-way analysis of variance with repeated measures will be applied to examine the main effects of the group, the time factor and group-time interaction effects. DISCUSSION: The results of the study protocol will provide high quality evidence for integrated synergy-based FES and RAT, and synergy-based FES alone and guide the design of more effective treatment methods for stroke rehabilitation. TRIAL REGISTRATION: ChiCTR2300071588.


Assuntos
Procedimentos Cirúrgicos Robóticos , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Adulto , Humanos , Qualidade de Vida , Acidente Vascular Cerebral/terapia , Estimulação Elétrica , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Zhongguo Zhong Yao Za Zhi ; 47(4): 1085-1094, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35285209

RESUMO

This study systematically searched CNKI and Web of Science(WoS) for the research papers on the toxicity of Tripterygium wilfordii included from database inception to August 31, 2021, and visually displayed the authors, research institutions, keywords, and other contents using bibliometrics and CiteSpace 5.8.3. Furthermore, the current situation and research progress on T. wilfordii safety were also analyzed based on information extraction to find the research hotspot, evolution path, and development trend, and to provide references for future research. A total of 1 876 Chinese papers and 243 English papers were included in the study. The analysis of authors showed that WANG Qi and ZHANG Luyong had the most publications in Chinese and English papers, respectively. According to the analysis of research institutions, National Institutes for Food and Drug Control and China Pharmaceutical University possessed the largest number of Chinese and English papers, respectively, but there was less cooperation between them. The analysis of keywords in Chinese and English papers showed that the research contents of the safety of T. wilfordii mainly focused on clinical monitoring, mechanism, dosage form improvement, quality standard, component analysis, monomer research, efficiency and toxicity reduction, etc. Metabonomics, tripterine, and the underlying mechanism of toxicity were the research hotspots in the future. At present, the research on the toxicity of T. wilfordii is still under development. It is necessary to highlight the in-depth research and strengthen the inter-group and inter-region cooperation of authors or institutions to provide references for the research on the toxicity of T. wilfordii.


Assuntos
Medicamentos de Ervas Chinesas , Tripterygium , Bibliometria , China , Medicamentos de Ervas Chinesas/toxicidade , Humanos
3.
Environ Sci Pollut Res Int ; 29(26): 39847-39859, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35112253

RESUMO

Environmental problems caused by the food processing industry have always been one of the concerns for the public. Herein, for the first time, a gate-to-gate life cycle assessment (LCA) was employed to evaluate the environmental impact of rice bran oil production. Four subsystems, namely, transportation of the raw rice bran to oil factory, crude oil extraction, oil refining, and oil storage, were established. The product sustainability software GaBi and the method CML 2001-Jan. 2016 were used to calculate and analyze the environmental burdens at each stage of the rice bran oil production chain. The results show the oil refining stage had the greatest environmental impact, followed by the oil extraction stage. High demands for coal and electricity make a critical difference in generating vast majority of environmental impacts. Modifying the electricity source and replacing traditional fuels with cleaner ones will do bring benefits to the sustainable development of the industry.


Assuntos
Oryza , Petróleo , Animais , Eletricidade , Meio Ambiente , Estágios do Ciclo de Vida , Óleo de Farelo de Arroz
4.
World J Clin Cases ; 9(3): 521-527, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33553390

RESUMO

With the development of endoscopic therapy, argon plasma coagulation (APC) has been widely used by endoscopists. It has many advantages, such as simple to operate, low cost, and minimal invasiveness. Because of its capability of lesion ablation and hemostasis, APC has several indications in the gastrointestinal tract. One of them is esophageal varices. The aim of this review is to summarize the research on APC in this field to provide a reference for clinical practice.

5.
Opt Express ; 28(8): 12460-12474, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32403743

RESUMO

We investigate the force measurement sensitivity in a squeezed dissipative optomechanics within the free-mass regime under the influence of shot noise (SN) from the photon number fluctuations, laser phase noise from the pump laser, thermal noise from the environment, and optical losses from outcoupling and detection inefficiencies. Generally, squeezed light could generate a reduced SN on the squeezed quadrature and an enlarged quantum backaction noise (QBA) due to the antisqueezed conjugate quadrature. With an appropriate choice of phase angle in homodyne detection, QBA is cancellable, leading to an exponentially improved measurement sensitivity for the SN-dominated regime. By now, the effects of laser phase noise that is proportional to laser power emerge. The balance between squeezed SN and phase noise can lead to an sub-SQL sensitivity at an exponentially lower input power. However, the improvement by squeezing is limited by optical losses because high sensitivity is delicate and easily destroyed by optical losses.

6.
Opt Express ; 26(23): 30773-30785, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30469969

RESUMO

We discuss the generation of strong stationary mechanical squeezing and entanglement in the modulated two-and three-mode optomechanics. Following the reservoir engineering scheme, the beam-splitter and parametric optomechanical interactions can be simultaneously achieved through appropriately choosing the modulation frequency on mechanical motion, which is essential to strong squeezing and entanglement. In the two-mode modulated optomechanics, squeezing is tunable by the relative ratio of parametric and beam-splitter couplings, and also robust to thermal noise due to the simultaneously optically induced cooling process. In the three-mode modulated optomechanics, strong EPR-type entanglement is also attainable, which can surpass the 3dB limit of nondegenerate parametric interaction. However, the ideal entanglement is impossible since only one of mechanical Bogoliubov modes is cooled by the cavity mode, which also makes the entanglement fragile to the mechanical noise.

7.
J Biotechnol ; 281: 144-149, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30016740

RESUMO

4-vinylguaiacol, a kind of volatile phenolic compound with tobacco flavor, is widely used as a component of edible flavor and intermediate of medicine. Ferulic acid is usually used as substrate for the biosynthesis of 4-vinylguaiacol. However, the price of ferulic acid is high, leading to high production cost. In this study, a feasible low-cost process for the production of 4-vinylguaiacol was developed. The ultrasonic assisted weak alkali was used to extract protein from rice bran, and waste liquid and residue were then mixed to extract crude ferulic acid by alkaline hydrolysis. Subsequently crude ferulic acid without further purification was directly converted into 4-vinylguaiacol via alginate-immo cells of the strain Bacillus licheniformis DLF-17056, which was newly isolated and highly active with ferulic acid conversion to 4-vinylguaiacol. 4-Vinylguaiacol could be produced up to 0.76 g/L from 1.0 g/L ferulic acid within 24 h biotransformation. Furthermore, the immobilized biocatalysts retained above 60% initial activity even after 8 times biotransformations. Thereby, it was assumed that our study would contribute to the industrial production of 4-vinylguaiacol from ferulic acid.


Assuntos
Bacillus licheniformis/metabolismo , Ácidos Cumáricos/metabolismo , Guaiacol/análogos & derivados , Alginatos , Bacillus licheniformis/genética , Biocatálise , Biotransformação , Células Imobilizadas/metabolismo , DNA Ribossômico/genética , Ácido Glucurônico , Guaiacol/metabolismo , Ácidos Hexurônicos , Oryza/química
8.
Plant Mol Biol ; 94(1-2): 61-78, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28247243

RESUMO

Hexokinase (HXK, EC 2.7.1.1) is a multifunctional protein that both is involved in catalyzing the first step of glycolysis and plays an important role in sugar signaling. However, the supporting genetic evidence on hexokinases (CsHXKs) from grape (Vitis vinifera L. cv. Cabernet Sauvignon) berries has been lacking. Here, to investigate the role of CsHXK isoforms as glucose (Glc) and abscisic acid (ABA) sensors, we cloned two hexokinase isozymes, CsHXK1 and CsHXK2 with highly conserved genomic structure of nine exons and eight introns. We also found adenosine phosphate binding, substrate recognition and connection sites in their putative proteins. During grape berry development, the expression profiles of two CsHXK isoforms, sucrose synthases (SuSys) and cell wall invertase (CWINV) genes increased concomitantly with high levels of endogenous Glc and ABA. Furthermore, we showed that in wild type grape berry calli (WT), glucose repressed the expression levels of sucrose synthase (SuSy) and cell wall invertase (CWINV) genes, while ABA increased their expression levels. ABA could not only effectively improve the expression levels of SuSy and CWINV, but also block the repression induced by glucose on the expression of both genes. However, after silencing CsHXK1 or CsHXK2 in grape calli, SuSy and CWINV expression were enhanced, and the expressions of the two genes are insensitive in response to Glc treatment. Interestingly, exogenous ABA alone could not or less increase SuSy and CWINV expression in silencing CsHXK1 or CsHXK2 grape calli compared to WT. Meantime, ABA could not block the repression induced by glucose on the expression of SuSy and CWINV in CsHXK1 or CsHXK2 mutants. Therefore, Glc signal transduction depends on the regulation of CsHXK1 or CsHXK2. ABA signal was also disturbed by CsHXK1 or CsHXK2 silencing. The present results provide new insights into the regulatory role of Glc and ABA on the enzymes related to sugar metabolism in grape berry.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucosiltransferases/metabolismo , Hexoquinase/metabolismo , Proteínas de Plantas/metabolismo , Vitis/enzimologia , beta-Frutofuranosidase/metabolismo , Ácido Abscísico/farmacologia , Sequência de Aminoácidos , Parede Celular/enzimologia , Frutas/enzimologia , Frutas/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Glucosiltransferases/genética , Hexoquinase/genética , Modelos Moleculares , Filogenia , Proteínas de Plantas/genética , Conformação Proteica , beta-Frutofuranosidase/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-25463198

RESUMO

(2S, 3R)-methyl-2-benzamidomethyl-3-hydroxybutyrate (MBHB) is a key intermediate in the synthesis of 4-aceoxyazetidinone, a building block for the production of penems and carbapenems. More attentions have been paid to screen biocatalysts achieving asymmetric preparation of (2S, 3R)-MBHB. In this study, an improved chiral high-performance liquid chromatographic (HPLC) method was developed for the stereoselective determination of 2-benzamidomethyl-3-oxobutanoate (BMOB) and MBHB, and further employed into the biotransformation of BMOB. Chiral separation was achieved within 12 min on Chiralpak AY-H column, which was faster and more suitable for screening biocatalysts exhibited reduction activity and (2S, 3R)-stereospecificity toward BMOB than on other columns. Ultimately, a new strain, Burkholderia gladioli ZJB-12126 capable of reducing BMOB to (2S, 3R)-MBHB was successfully isolated based on this newly constructed HPLC method. Samples were prepared by liquid-liquid extraction system using ethyl acetate as the extractor solvent. The extraction recoveries of BMOB and MBHB isomers ranged from 91.6 to 94.1% with relative standard deviation (RSD) below 10%. Linear calibration curves were obtained in the concentration range of 50-5000 µg/mL for both BMOB and MBHB isomers, respectively. Intra-day and inter-day precisions and accuracy were below 15% for all isomers evaluated by RSDs and relative errors (REs), respectively. This novel method was demonstrated to be suitable for assessing the biotransformation process of BMOB.


Assuntos
Burkholderia gladioli/metabolismo , Butiratos/química , Cromatografia Líquida de Alta Pressão/métodos , Biotransformação , Burkholderia gladioli/química , Butiratos/metabolismo , Estereoisomerismo
10.
Org Biomol Chem ; 12(14): 2167-71, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24569962

RESUMO

The cinchona alkaloid-catalyzed [4 + 2] cyclocondensation of α,ß-unsaturated acyl chlorides with imines is developed to give the corresponding substituted dihydropyridinones in good yields with high to excellent enantioselectivities. Reduction of the dihydropyridinones gave highly optically active substituted tetrahydropyridinone and piperidine derivatives.


Assuntos
Alcaloides de Cinchona/química , Di-Hidropiridinas/síntese química , Hidrocarbonetos Clorados/química , Iminas/química , Piperidinas/síntese química , Piridonas/síntese química , Catálise , Ciclização , Di-Hidropiridinas/química , Estrutura Molecular , Piperidinas/química , Piridonas/química , Estereoisomerismo
11.
J Agric Food Chem ; 61(44): 10582-9, 2013 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-24107219

RESUMO

The control of self-assembly of sodium caseinate (SC) including the formation of mixed layers, microspheres, or nanoparticles is highly relevant to the microstructure of food and the design of promising drug delivery systems. In this paper, we designed a structure-switchable zwitterionic bolaamphiphile, 1,12-diaminododecanediorotate (DDO), from orotic acid, which has special binding sites and can guide the self-assembly of SC. Complexation between SC and DDO was investigated using dynamic light scattering, transmission electron microscopy, differential scanning calorimetry, and fluorescence spectra measurements. Monomeric DDO was bound to the negatively charged sites on the SC micelle and made the structure of SC more compact with decreased electrostatic repulsion between the head groups. Vesicular DDO led to reassociation of vesicles with enlarged size via preferable hydrophobic interactions. Moreover, the aggregation between SC and DDO was found to be temperature-dependent and reversible. This research provides an effective way to control the reversible self-assembly of SC by the zwitterionic vitamin-derived bolaamphiphile.


Assuntos
Caseínas/química , Furanos/química , Piridonas/química , Vitaminas/química , Varredura Diferencial de Calorimetria , Micelas , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Espalhamento de Radiação , Temperatura
14.
Chemistry ; 19(14): 4441-5, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23450776

RESUMO

NHC catalysis: N-heterocyclic carbenes were found to be efficient catalysts for the unprecedented [4+2] cycloaddition of nitroalkenes and oxodienes, giving the corresponding dihydropyrans in good yield with good diastereoselectivity (see scheme). Deuteration experiment reveals that the reaction is possibly initiated by the addition of N-heterocylic carbene to nitroalkenes.

15.
Org Biomol Chem ; 11(1): 158-63, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23117299

RESUMO

The N-heterocyclic carbene-catalyzed [4 + 2] cyclization of ketenes and 3-aroylcoumarins has been developed to give the corresponding dihydrocoumarin-fused multisubstituted dihydropyranones in high yield with good diastereoselectivity and high enantioselectivity.


Assuntos
Cumarínicos/química , Etilenos/química , Compostos Heterocíclicos/química , Cetonas/química , Metano/análogos & derivados , Pironas/síntese química , Catálise , Cristalografia por Raios X , Ciclização , Metano/química , Modelos Moleculares , Estrutura Molecular , Pironas/química , Estereoisomerismo
16.
Food Chem ; 134(2): 948-56, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23107712

RESUMO

5'-Nucleotides including 5'-inosinic acid have characteristic taste and important application in various foods as flavour potentiators. The selective nucleoside acid phosphatase/phosphotransferase (AP/PTase) can catalyse the synthesis of 5'-nucleotides by transfer of phosphate groups. In this study, a 747-bp gene encoding AP/PTase from Escherichia blattae was synthesised. After expression, the recombinant AP/PTase was purified using nickel-NTA. The optimal temperature and pH of this enzyme were 30°C and 5.0, respectively. The activity was partially inhibited by metal ions such as Hg(2+), Ag(+) and Cu(2+), but not by chelating reagents such as EDTA. The values of K(m) and V(max) for inosine were 40 mM and 3.5 U/mg, respectively. Using this purified enzyme, 16.83 mM of 5'-IMP was synthesised from 37 mM of inosine and the molar yield reached 45.5%. Homology modelling and docking simulation were discussed.


Assuntos
Fosfatase Ácida/metabolismo , Proteínas de Bactérias/metabolismo , Escherichia/enzimologia , Inosina Monofosfato/metabolismo , Fosfotransferases/metabolismo , Fosfatase Ácida/química , Fosfatase Ácida/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Estabilidade Enzimática , Escherichia/genética , Escherichia/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Cinética , Fosfotransferases/química , Fosfotransferases/genética
17.
Chem Commun (Camb) ; 48(88): 10907-9, 2012 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-23023792

RESUMO

Highly functionalized dihydropyridinones were synthesized via the N-heterocyclic carbene-catalyzed enantioselective [4 + 2] annulation of α-chloroaldehydes and azadienes. Hydrogenation of the resulted dihydropyridinones afforded the corresponding piperidinones with high enantiopurity.


Assuntos
Aldeídos/química , Compostos Aza/química , Metano/análogos & derivados , Piridonas/química , Ciclização , Hidrogenação , Metano/química , Estrutura Molecular , Estereoisomerismo
18.
Chemistry ; 18(30): 9198-203, 2012 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-22736551

RESUMO

In pole position: A simple and efficient approach to spirocyclic γ-lactam oxindoles by the N-heterocyclic carbene catalyzed addition of homoenloate equivalents to N-aryl isatinimines has been developed (see scheme). The use of N-aryl isatinimines as electrophiles in the NHC-catalyzed umpolung reaction of α,ß-unsaturated aldehydes is demonstrated for the first time.


Assuntos
Compostos Heterocíclicos/química , Iminas/química , Indóis/química , Indóis/síntese química , Lactamas/química , Lactamas/síntese química , Metano/análogos & derivados , Nitrilas/química , Compostos de Espiro/química , Compostos de Espiro/síntese química , Catálise , Metano/química , Estrutura Molecular , Oxindóis , Estereoisomerismo
19.
J Microbiol Biotechnol ; 22(6): 826-31, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22573161

RESUMO

Acarbose, a pseudo-oligosaccharide, is widely used clinically in therapies for non-insulin-dependent diabetes. In the present study, S-adenosylmethionine (SAM) was added to selected media in order to investigate its effect on acarbose fermentation by Actinoplanes utahensis ZJB- 08196. Acarbose titer was seen to increase markedly when concentrations of SAM were added over a period of time. The effects of glucose and maltose on the production of acarbose were investigated in both batch and fed-batch fermentation. Optimal acarbose production was observed at relatively low glucose levels and high maltose levels. Based on these results, a further fed-batch experiment was designed so as to enhance the production of acarbose. Fed-batch fermentation was carried out at an initial glucose level of 10 g/l and an initial maltose level of 60 g/l. Then, 12 h post inoculation, 100 micromol/l SAM was added. In addition, 8 g/l of glucose was added every 24 h, and 20 g/l of maltose was added at 96 h. By way of this novel feeding strategy, the maximum titer of acarbose achieved was 6,113 mg/l at 192 h. To our knowledge, the production level of acarbose achieved in this study is the highest ever reported.


Assuntos
Acarbose/metabolismo , Micromonosporaceae/metabolismo , S-Adenosilmetionina/metabolismo , Biotecnologia/métodos , Meios de Cultura/química , Fermentação , Glucose/metabolismo , Maltose/metabolismo , Micromonosporaceae/crescimento & desenvolvimento
20.
Opt Express ; 20(3): 3176-91, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22330555

RESUMO

Two schemes for the preparation of weighted continuous variable cluster states with four atomic ensembles are proposed. In the first scheme, the four separated atomic ensembles inside a two-mode ring cavity are driven by pulse laser fields. The basic idea of the scheme is to transfer the ensemble bosonic modes into suitable linear combinations that can be prepared in a pure cluster state by a sequential application of the laser pulses with the aid of the cavity dissipation. In the second one, we take two separate two-mode cavities, each containing two atomic ensembles. The distant cavities are coupled by dissipation in a cascade way. It has been found that the mixed cluster state can be produced. These schemes may contribute towards implementing continuous variable quantum computation, quantum communication and networking based on atomic ensembles.


Assuntos
Modelos Teóricos , Simulação por Computador , Luz , Espalhamento de Radiação
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