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1.
Small ; : e2403056, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726792

RESUMO

Energy conversion and transfer of enzyme-catalyzed reactions at molecular level are an interesting and challenging scientific topic that helps understanding biological processes in nature. In this study, it is demonstrated that enzyme-catalyzed reactions can enhance diffusion of surrounding molecules and thus accelerate cargo transport within 1D micro/nanochannels. Specifically, urease is immobilized on the inner walls of silica micro/nano-tubes to construct bio-catalytically active micro/nanochannels. The catalytic reaction inside the channels drives a variety of cargoes, including small dye molecules, polymers, and rigid nanoparticles (e.g., quantum dots, QDs), to pass through these micro/nanochannels much faster than they will by free diffusion. The enhanced diffusion of molecular species inside the channels is validated by direct observation of the Brownian motion of tracer particles, and further confirmed by significantly enhanced Raman intensity of reporter molecules. Finite element and Brownian dynamics simulations provide a theoretical understanding of these experimental observations. Furthermore, the effect of the channels' size on the diffusion enhancement is examined. The acceleration effect of the cargo transport through these enzymatically active micro/nanochannels can be turned on or off via chemical activators or inhibitors. This study provides valuable insights on the design of biomimetic channels capable of controlled and efficient transmembrane transport.

2.
Sleep Breath ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888794

RESUMO

Obstructive sleep apnea (OSA) has received considerable attention as a potential risk factor for depressive symptoms. The systematic review was conducted to confirm the dose‒response connection between OSA severity and depression risk. A systematic literature search of English and Chinese articles published in PubMed, EMBASE, Scopus, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), and SinoMed databases from their inception to 28 August 2023 was conducted. An evaluation using the Newcastle‒Ottawa Scale was performed. A meta-analysis was used to evaluate the impact of OSA severity. A random-effects dose‒response model was conducted to evaluate the linear and nonlinear dose‒response connections. We evaluated publication bias by funnel plots, and symmetry by Egger's test. We identified 18 cross-sectional researches. 3143 participants which were involved in the dose‒response meta-analysis. Contrasted with mild OSA, individuals with severe OSA had a higher adjusted risk of depression (rate ratio: 1.34, 95% confidence interval = 1.05-1.70), with substantial heterogeneity (I2 = 70.9%, Pheterogeneity<0.001). There is a significant linear connection between OSA severity and depression risk. The depression risk increased by 0.4% for every 1 event per hour increase in the apnea-hypopnea index (AHI). The protocol for this unfunded research was drafted and registered at PROSPERO (ID CRD42023474097).

3.
Sensors (Basel) ; 24(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38475080

RESUMO

The performance of a hemispherical resonant gyroscope (HRG) is directly affected by the sphericity error of the thin-walled spherical shell of the hemispherical shell resonator (HSR). In the production process of the HSRs, high-speed, high-accuracy, and high-robustness requirements are necessary for evaluating sphericity errors. We designed a sphericity error evaluation method based on the minimum zone criterion with an adaptive number of subpopulations. The method utilizes the global optimal solution and the subpopulations' optimal solution to guide the search, initializes the subpopulations through clustering, and dynamically eliminates inferior subpopulations. Simulation experiments demonstrate that the algorithm exhibits excellent evaluation accuracy when processing simulation datasets with different sphericity errors, radii, and numbers of sampling points. The uncertainty of the results reached the order of 10-9 mm. When processing up to 6000 simulation datasets, the algorithm's solution deviation from the ideal sphericity error remained around -3 × 10-9 mm. And the sphericity error evaluation was completed within 1 s on average. Additionally, comparison experiments further confirmed the evaluation accuracy of the algorithm. In the HSR sample measurement experiments, our algorithm improved the sphericity error assessment accuracy of the HSR's inner and outer contour sampling datasets by 17% and 4%, compared with the results given by the coordinate measuring machine. The experiment results demonstrated that the algorithm meets the requirements of sphericity error assessment in the manufacturing process of the HSRs and has the potential to be widely used in the future.

4.
Inflamm Res ; 72(4): 703-713, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36745209

RESUMO

OBJECTIVE AND DESIGN: The age-associated increases in aseptic inflammation and necroptosis are closely related to the emergence of various age-associated diseases. METHODS: In this study, the role of HMGB1/TLR4-induced necroptosis in abdominal aortic aneurysm (AAA) formation was investigated. First, the levels of sterile inflammatory mediators (HMGB1, TLR4) and necroptosis markers were measured in the abdominal aortas of young and old C57BL/6JNifdc mice. We observed that sterile inflammatory mediators and necroptosis markers were greatly increased in the abdominal aortas of old mice. Then, angiotensin II (Ang II)-induced AAA model in APOE-/- mice was used in this study. Mice AAA models were treated with the RIP1 inhibitor necrostatin-1 (Nec-1) or the TLR4 inhibitor TAK-242, respectively. RESULTS: We found that HMGB1, TLR4, and necroptosis markers were elevated in old mice compared with those in young mice. Same elevation was also found in the development of AAA in APOE-/- mice. In addition, the necroptosis inhibitor Nec-1 alleviated Ang II-induced AAA development while downregulating the expression of HMGB1/TLR4. After blocking TLR4 with TAK-242, the expression of necroptosis markers decreased significantly, and the progression of AAA was also alleviated in APOE-/- mice. CONCLUSIONS: Our results indicated that HMGB1/TLR4-mediated necroptosis enhances AAA development in the Ang II-induced AAA model in APOE-/- mice and that TLR4 might be a potential therapeutic target for AAA management.


Assuntos
Aneurisma da Aorta Abdominal , Proteína HMGB1 , Camundongos , Animais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Proteína HMGB1/metabolismo , Necroptose , Camundongos Endogâmicos C57BL , Aneurisma da Aorta Abdominal/induzido quimicamente , Aorta Abdominal/metabolismo , Transdução de Sinais , Mediadores da Inflamação/metabolismo , Apolipoproteínas E/efeitos adversos , Apolipoproteínas E/metabolismo , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Modelos Animais de Doenças , Camundongos Knockout
5.
Brain Topogr ; 36(2): 243-254, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36697933

RESUMO

Mindfulness meditation helps to improve attentional capacity. However, the neural correlates that indicate the mechanism through which mindfulness improves attention are unclear. To address this gap, we aimed to assess the effects of mindfulness training on sustained attentional capacity. Event-related potentials (ERPs) associated with the modified sustained attention response task (mSART) were used in this study. A total of 45 college students were randomly assigned to either the mindfulness group (n = 21) or the control group (n = 24). Participants in the mindfulness group received a three-week mindfulness training. The self-report results showed that the mindfulness group reported higher mindfulness scores (observing and non-judgment of inner experiences) after the training. The mindfulness group also scored lower on the state anxiety than the control group. Behavioral results also showed that self-caught mind wandering in the mindfulness group significantly decreased after the training, and the mindfulness group showed a faster response after the training. The ERP results showed that N2 amplitudes in the post-test were significantly greater than those in the pre-test in the mindfulness group. We did not find any interactions between group and time for P3. The findings suggest that mindfulness training can effectively improve sustained attentional capacity, as indicated by reduced mind wandering and increased N2 responses.


Assuntos
Atenção Plena , Humanos , Atenção Plena/métodos , Potenciais Evocados/fisiologia , Atenção/fisiologia
6.
Sensors (Basel) ; 23(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37631610

RESUMO

Harmonic and interharmonic content in power system signals is increasing with the development of renewable energy generation and power electronic devices. These multiple signal components can seriously degrade power quality, trip thermal generators, cause oscillations, and threaten system stability, especially the interharmonic tones with positive damping factors. The first step to mitigate these adverse effects is to accurately and quickly monitor signal features, including frequency, damping factor, amplitude, and phase. This paper proposes a concise and robust index to identify the number of modes present in the signal using the singular values of the Hankel matrix and discusses the scope of its application by testing the influence of various factors. Next, the simplified matrix pencil theory is employed to estimate the signal component frequency and damping factor. Then their estimates are considered in the modified least-squares algorithm to extract the wideband multi-component phasors accurately. Finally, this paper designs a series of scenarios considering varying signal frequency, damping factor, amplitude, and phase to test the proposed algorithm thoroughly. The results verify that the proposed method can achieve a maximum total vector error of less than 1.5%, which is more accurate than existing phasor estimators in various signal environments. The high accuracy of the proposed method is because it considers both the estimation of the frequency number and the effect of signal damping.

7.
Int J Mol Sci ; 24(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37047249

RESUMO

A high oleic acid content is considered an essential characteristic in the breeding of high-quality rapeseed in China. Long-chain non-coding RNA (lncRNA) molecules play an important role in the plant's growth and its response to stress. To better understand the role of lncRNAs in regulating plant reproductive development, we analyzed whole-transcriptome and physiological data to characterize the dynamic changes in lncRNA expression during the four representative times of seed development of high- and low-oleic-acid rapeseed in three regions. We identified 21 and 14 lncRNA and mRNA modules, respectively. These modules were divided into three types related to region, development stages, and material. Next, we analyzed the key modules related to the oil content and the oleic acid, linoleic acid, and linolenic acid contents with physiological data and constructed the key functional network analysis on this basis. Genes related to lipid metabolism, such as 3-ketoacyl-CoA synthase 16 (KCS16) and acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), were present in the co-expression network, suggesting that the effect of these genes on lipid metabolism might be embodied by the expression of these lncRNAs. Our results provide a fresh insight into region-, development-stage-, and material-biased changes in lncRNA expression in the seeds of Brassica napus. Some of these lncRNAs may participate in the regulatory network of lipid accumulation and metabolism, together with regulated genes. These results may help elucidate the regulatory system of lncRNAs in the lipid metabolism of high-oleic-acid rapeseed seeds.


Assuntos
Brassica napus , Brassica rapa , RNA Longo não Codificante , Brassica napus/genética , Brassica napus/metabolismo , Ácido Oleico/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Óleos de Plantas/metabolismo , Metabolismo dos Lipídeos/genética , Melhoramento Vegetal , Brassica rapa/genética , Brassica rapa/metabolismo , Sementes/metabolismo
8.
Angew Chem Int Ed Engl ; 62(23): e202302101, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37017109

RESUMO

Although great successes have been achieved, the preparation of closed-loop recyclable polyesters with high working temperatures still remains as a big challenge. Herein, we present the syntheses of a series of enantiopure bicyclic ether-ester monomers by upcycling of poly(3-hydroxybutyrate) bioplastic. The "living"/controlled ring-opening polymerizations of these enantiopure monomers to produce stereoregular polyesters with controlled molecular weights and well-defined chain ends were achieved. The effects of stereoconfiguration and substituent on polymerization kinetics and thermodynamics as well as the thermal properties of resultant polyesters were investigated. Of note, the stereoregular polyesters are semi-crystalline materials with melting temperatures up to 176 °C, even higher than the commodity polyolefin plastics. These polyesters can be depolymerized back to recover pristine monomers, thus successfully establishing a closed-loop life cycle.

9.
Cogn Affect Behav Neurosci ; 22(2): 403-413, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34750754

RESUMO

Empathy can be measured based on behavioral tasks and self-report scales, which have been used to characterize the state and trait empathy, respectively, in previous studies. The neural correlates of state empathy have been deeply investigated, whereas the association between trait empathy and brain activity remains unclear. Thus, this study employed multiple variate pattern analysis (MVPA) to explore whether intrinsic brain activity (IBA) within state-empathy-related regions was associated with trait empathy. Meta-analysis of empathy-related fMRI experiments identified a general network underlying state empathy, which is located in the bilateral supplementary motor area (SMA) extending to the middle cingulate cortex (MCC) and left anterior insula (AI) and extending to the inferior frontal gyrus (IFG). The subsequent MVPA found that empathic concern can be predicted through the IBA of the general network at the female individual level (i.e., the fractional amplitude of low-frequency fluctuations and regional homogeneity). Based on the resting state fMRI (rs-fMRI), these results further support the involvement of SMA/MCC and AI/IFG in empathy. Meanwhile, the significant predictive association between IBA and trait empathy offers new insights into the general component of empathy, which may indicate the potential of using rs-fMRI to achieve the objective measurement of empathic ability.


Assuntos
Mapeamento Encefálico , Empatia , Encéfalo/diagnóstico por imagem , Feminino , Giro do Cíngulo , Humanos , Imageamento por Ressonância Magnética/métodos
10.
Anal Bioanal Chem ; 413(2): 533-541, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33164153

RESUMO

A UV-vis spectrometer, as a sort of important analytical instrument, has been widely used to analyze various substances. However, expensive equipment and skilled operators are required, which limits its broad applications for out-of-lab and daily measurements. In this work, a self-designed sensing device based on smart phone was developed as a sensitive, cost-effective, facile, and portable testing tool. The sensing device fabricated by 3D printing was used to lodge a sample solution and produce a light signal, and the optical sensor on a smart phone worked as a transducer. The light source in the device generated wide-wavelength radiation, which passed through an inner filter and only light of a designated wavelength reached the testing solution. The intensity of transmitted light was then measured by an optical sensor internally installed in most smart phones, where the signals were processed as well. The feasibility of our device was verified by detecting four kinds of common heavy metal ions in actual water samples, and the testing results showed good agreement with those obtained from the UV-vis spectrometer. This work is expected to shed some light on the construction of smart phone-based sensors, featuring decent portability, simple operation, low cost, high sensitivity, and good accuracy.

11.
J Enzyme Inhib Med Chem ; 36(1): 1079-1087, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34030574

RESUMO

Inhibitors of COMT are clinically used for the treatment of Parkinson's disease. Here, we report the first natural pentacyclic triterpenoid-type COMT inhibitors and their structure-activity relationships and inhibition mechanism. The most potent compounds were found to be oleanic acid, betulinic acid and celastrol with IC50 values of 3.89-5.07 µM, that acted as mixed (uncompetitive plus non-competitive) inhibitors of COMT, representing a new skeleton of COMT inhibitor. Molecular docking suggested that they can specifically recognise and bind with the unique hydrophobic residues surrounding the catechol pocket. Furthermore, oleanic acid and betulinic acid proved to be less disruptive of mitochondrial membrane potential (MMP) compared to tolcapone, thus reducing the risk of liver toxicity. These findings could be used to produce an ideal lead compound and to guide synthetic efforts in generating related derivatives for further preclinical testing.


Assuntos
Produtos Biológicos/farmacologia , Catecol O-Metiltransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Triterpenos Pentacíclicos/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Cinética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Conformação Molecular , Simulação de Acoplamento Molecular , Triterpenos Pentacíclicos/síntese química , Triterpenos Pentacíclicos/química , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
12.
Cogn Affect Behav Neurosci ; 20(1): 115-127, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31823210

RESUMO

Previous research has revealed that interpersonal relationships and social comparisons play important roles in evaluating outcomes. To our knowledge, how interpersonal relationships influence the process of outcome evaluations in a social comparison context remains largely unclear. In the current study, participants engaged in a simple gambling task with an acquaintance or a stranger and received outcome feedback. Behavioral results showed that participants' satisfaction level was sensitive to the outcome of their fellow players when participants won. In this condition, the satisfaction level was greater when their fellow players won rather than lost. Moreover, the satisfaction level was greater when their friends won compared with when a stranger won. Event-related potential (ERP) results showed that when participants won, the feedback-related negativity (FRN) was more negative going for other's losses than for other's gains. Moreover, the FRN was also more negative going for a stranger's gains than a friend's gains. In contrast, in the self-loss condition, the FRN was more negative going for other's gains than for other's losses regardless of the type of interpersonal relationship. These FRN findings indicate that the experience of other's outcomes is sensitive to participants' own outcomes. Importantly, the interpersonal relationship only showed its influence when both the self and others received monetary gains. Finally, the P300 registered participants' attention resource allocation toward monetary gains for themselves and for others, which was unaffected by the interpersonal relationship. This work reveals that outcome evaluation in various social comparison contexts is sensitive to the difference in interpersonal relationship in its early stage, labeled by the FRN.


Assuntos
Potenciais Evocados/fisiologia , Relações Interpessoais , Dor/fisiopatologia , Comparação Social , Adulto , Encéfalo/fisiopatologia , Eletroencefalografia/métodos , Retroalimentação Psicológica/fisiologia , Feminino , Humanos , Masculino , Meio Social , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-33666545

RESUMO

A Gram-stain-variable, aerobic, rod-shaped, endospore-forming strain R196T) was isolated from internal tissues of roots of Cymbidium goeringii. Cells were motile with peritrichous flagella. The colonies were light pink on tryptone soya agar medium. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain R196T fell into a phylogenetic cluster belonging to the genus Paenibacillus. Strain R196T was closely related to Paenibacillus cavernae C4-5T and Paenibacillus contaminans CKOBP-6T with 93.6 and 93.3% sequence similarities, respectively. The major cellular polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, three unidentified phospholipids, two unidentified aminophospholipids and an unidentified aminolipid. The dominant respiratory quinone was MK-7. The main cellular fatty acids were anteiso-C15 : 0 (53.01%), C16 : 0 (13.04%) and iso-C16 : 0 (10.80%). The genome size of R196T was 9.45 Mb, containing 7617 predicted protein-coding genes, with a DNA G+C content of 57.7 mol%. Based on the results of phenotypic, chemotaxonomic and whole-genome analyses, strain R196T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus cymbidii sp. nov. is proposed. The type strain is R196T (=ACCC 61713T=KCTC 33718T).

14.
Appl Microbiol Biotechnol ; 103(15): 6169-6186, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31165225

RESUMO

Ulcerative colitis (UC) is a chronic relapsing disease. Treatment of UC would benefit from specific targeting of therapeutics to the intestine. Previous studies have demonstrated that bovine lactoferricin and lactoferrampin have bactericidal, anti-inflammatory, and immunomodulatory effects. Here, we investigated whether oral administration of a bovine lactoferricin-lactoferrampin (LFCA)-encoding Lactococcus lactis (LL-LFCA) strain could alleviate experimental colitis. LFCA derived from LL-LFCA inhibited the growth of Escherichia coli and Staphylococcus aureus in vitro. In mice, administration of LL-LFCA decreased the disease activity index and attenuated dextran sulfate sodium (DSS)-induced body weight loss and colon shortening. LL-LFCA treatment also ameliorated DSS-induced colon damage, inhibited inflammatory cell infiltration, significantly decreased myeloperoxidase activity, and ameliorated DSS-induced disruption of intestinal permeability and tight junctions. In addition, 16S rDNA sequencing showed that LL-LFCA reversed DSS-induced gut dysbiosis. The production of proinflammatory mediators in serum and the colon was also reduced by administration of LL-LFCA. In vitro, LFCA derived from LL-LFCA decreased the messenger RNA expression of proinflammatory factors. The underlying mechanisms may involve inhibition of the nuclear factor kappa B (NF-κB) pathway. The results demonstrate that LL-LFCA ameliorates DSS-induced intestinal injury in mice, suggesting that LL-LFCA might be an effective drug for the treatment of inflammatory bowel diseases.


Assuntos
Antibacterianos/metabolismo , Colite/patologia , Colite/terapia , Lactococcus lactis/metabolismo , Lactoferrina/metabolismo , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes/metabolismo , Animais , Colite/induzido quimicamente , Modelos Animais de Doenças , Disbiose/terapia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Microbioma Gastrointestinal/efeitos dos fármacos , Lactococcus lactis/genética , Lactococcus lactis/crescimento & desenvolvimento , Lactoferrina/genética , Camundongos , Fragmentos de Peptídeos/genética , Proteínas Recombinantes/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Resultado do Tratamento
15.
Sensors (Basel) ; 19(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769893

RESUMO

The wireless sensor network (WSN) is mainly composed of a large number of sensor nodes that are equipped with limited energy and resources. Therefore, energy consumption in wireless sensor networks is one of the most challenging problems in practice. On the other hand, data fusion can effectively decrease data redundancy, reduce the amount of data transmission and energy consumption in the network, extend the network life cycle, improve the utilization of bandwidth, and thus overcome the bottleneck on energy and bandwidth consumption. This paper proposes a new data fusion algorithm based on Hesitant Fuzzy Entropy (DFHFE). The new algorithm aims to reduce the collection of repeated data on sensor nodes from the source, and strives to utilize the information provided by redundant data to improve the data reliability. Hesitant fuzzy entropy is exploited to fuse the original data from sensor nodes in the cluster at the sink node to obtain higher quality data and make local decisions on the events of interest. The sink nodes periodically send local decisions to the base station that aggregates the local decisions and makes the final judgment, in which process the burden for the base station to process all the data is significantly released. According to our experiments, the proposed data fusion algorithm greatly improves the robustness, accuracy, and real-time performance of the entire network. The simulation results demonstrate that the new algorithm is more efficient than the state-of-the-art in terms of both energy consumption and real-time performance.

16.
Int J Syst Evol Microbiol ; 67(8): 2928-2933, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28853686

RESUMO

A novel endophytic bacterium, strain J11-6T, was isolated from rice stems. Its taxonomic position was investigated using a polyphasic approach. The novel strain was Gram-staining-negative, facultatively anaerobic, motile and rod-shaped. Although the results of phylogenetic analysis based on 16S rRNA gene sequences indicated that J11-6T represented a member of the genus Rahnella, multilocus sequence analysis (MLSA) on the basis of concatenated partial atpD, gyrB, rpoB and infB gene sequences showed a clear distinction of J11-6T from the type strains of species of the genus Rahnella but indicated that it lay within the clade of the genus Serratia. The phylogenetically closest species were Serratia fonticola and Serratia aquatilis on the basis of the results of the MLSA phylogenetic analysis. The predominant cellular fatty acids were C16 : 1ω7c (38.7 %) and C16 : 0 (25.0 %). The DNA G+C content was 53.2 mol%. The DNA-DNA relatedness was 17.4 % between J11-6T and Rahnella aquatilis CIP 78.65T, and 29.2 % between J11-6T and S. fonticola LMG 7882T which indicates that this strain represents a novel species of the genus Serratia. Characterization by genotypic and phenotypic analysis indicated that J11-6T (=ACCC 19934T=KCTC 52529T) represents a novel species of the genus Serratia, for which the name Serratia oryzae sp. nov. is proposed.


Assuntos
Oryza/microbiologia , Filogenia , Caules de Planta/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Serratia/genética
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(10): 2820-4, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26904825

RESUMO

A spectrophotometric method for the determination of flavonoids content in Waste Residue of Stevia Rebaudiana was established by comparing the UV-Vis spectra with three spectrophotometric methods: Direct, AlCl3 and NaNO2-Al (NO3)3-NaOH method. The effects of spectrophotometric reaction were studied by analyzing the wavelength, the dosage of color development reagent, reaction time, temperature and pH. The further research was studied by analyzing linearity between the absorbance and the concentration, the stability of this color system, the recovery rate and so on. The results showed that NaNO2-Al(NO3)3-NaOH method was best. The wavelength was 500 nm. The standard sample was rutin. There was a good linear relationship in the ranges of 2 - 24 µg x mL(-1), correlation coefficient R2 = 0.999 5. The recovery of the additional sample was 96.0%-104.3%. The relative standard deviation(RSD) is respectively 3.75%. The dosages of NaNO2 and Al(NO3)3 both were 1.0 mL, both of their reaction time was 6 min. The dosage of NaOH was 15.0 mL and the reaction time was 15 min. The temperature in the whole process of the reaction must be maintained at 40 degrees C and pH is 5. The spectrophotometric condition was further improved on the determination of flavonoids content. This method, which is simple, rapid and accuracy, can be used in practical application.


Assuntos
Flavonoides , Stevia , Cloreto de Alumínio , Compostos de Alumínio , Cloretos , Indicadores e Reagentes , Reprodutibilidade dos Testes , Pesquisa , Rutina , Espectrofotometria , Temperatura
18.
Ann Cardiothorac Surg ; 13(2): 165-172, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38590995

RESUMO

Background: Thoracoscopic ablation (TA) has emerged as a promising treatment for atrial fibrillation (AF), with the Cox-Maze IV Procedure (CMP-IV) as the current gold-standard intervention. This study aims to evaluate and compare the outcomes of TA and CMP-IV in treating AF. Methods: Patients with AF underwent either CMP-IV or TA through a left-side chest approach. The CMP-IV entailed bi-atrium ablation, whereas the TA involved creating three circular plus three linear ablations in the left atrium. We analyzed baseline characteristics, perioperative outcomes and recurrence rates using propensity score matching (PSM) at a 1:1 ratio, to ensure comparability between the two treatment groups. Results: A total of 459 patients underwent either CMP-IV (n=93) or TA via left chest (n=366) and 174 patients were deemed eligible for 1:1 PSM. The TA group experienced significantly shorter intensive care unit (ICU) and hospital stays. The mean follow-up period was 31.5±22.1 months. Pre- and post-matching analysis showed that CMP-IV had a higher rate of freedom from recurrence compared to TA, particularly in non-paroxysmal AF patients. Multivariable Cox regression analysis revealed that CMP-IV was associated with a reduced risk of recurrence, while an increased left atrial size emerged as an independent predictor of postoperative recurrence, regardless of the use of CMP-IV or TA. Conclusions: Our study suggests that while the therapeutic efficacy of TA for "lone" AF may fall short of the classic CMP-IV, its less invasive nature results in significantly shorter ICU and hospital stays. To enhance patient outcomes following TA, it is essential to improve the quality of ablation, refine the ablation route, and focus on careful patient selection.

19.
Atherosclerosis ; 392: 117483, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38490134

RESUMO

BACKGROUND AND AIMS: In this study, we carried out a clinical sample study, and in vivo and in vitro studies to evaluate the effect of SIRT6 and SIRT6-mediated vascular smooth muscle senescence on the development of abdominal aortic aneurysm (AAA). METHOD AND RESULTS: AAA specimen showed an increased P16, P21 level and a decreased SIRT6 level compared with control aorta. Time curve study of Ang II infusion AAA model showed similar P16, P21 and SIRT6 changes at the early phase of AAA induction. The in vivo overexpression of SIRT6 significantly prevented AAA formation in Ang II infusion model. The expression of P16 and P21 was significantly reduced after SIRT6 overexpression. SIRT6 overexpression also attenuated chronic inflammation and neo-angiogenesis in Ang II infusion model. The overexpression of SIRT6 could attenuate premature senescence, inflammatory response and neo-angiogenesis in human aortic smooth muscle cells (HASMC) under Ang II stimulation. CONCLUSIONS: SIRT6 overexpression could limit AAA formation via attenuation of vascular smooth muscle senescence, chronic inflammation and neovascularity.


Assuntos
Angiotensina II , Aneurisma da Aorta Abdominal , Senescência Celular , Músculo Liso Vascular , Miócitos de Músculo Liso , Sirtuínas , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/patologia , Sirtuínas/metabolismo , Sirtuínas/genética , Humanos , Músculo Liso Vascular/patologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Masculino , Animais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Aorta Abdominal/patologia , Aorta Abdominal/metabolismo , Células Cultivadas , Neovascularização Patológica , Idoso , Pessoa de Meia-Idade , Inflamação , Camundongos Endogâmicos C57BL
20.
Front Psychiatry ; 15: 1341294, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38563033

RESUMO

Introduction: Attentional enhancement has often been identified as the central cognitive mechanism underlying the benefits of mindfulness meditation. However, the extent to which this enhancement is observable in the neural processes underlying long-term meditation is unclear. This current study aimed to examine differences in attentional performance between meditators and controls (non-meditators) using a visual oddball task with concurrent electroencephalography (EEG) recordings. Methods: Thirty-four participants were recruited, including 16 meditators and 18 healthy controls, who were non-meditators. The participants completed a visual oddball task, using visual stimuli, and EEG recording. Results: Self-reports revealed that meditators had higher mindful attention scores than did the control group. The behavioral results showed that the meditators demonstrated faster reaction times than the non-meditators did. Neural findings indicated a higher P2 amplitude in the meditators than in the controls. The meditators demonstrated a significantly higher P3 in the target trials than in the distractor trials, which was not observed in the controls. Additionally, the time-frequency analysis demonstrated that the delta and theta powers in the meditators were significantly higher than those in the controls. Conclusions: The study suggests the meditators exhibited greater attentional performance than the controls did, as revealed by EEG and behavioral measures. This study extends previous research on the effects of mindfulness meditation on attention and adds to our understanding of the effects of long-term mindfulness meditation.

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