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1.
Int J Biol Macromol ; 271(Pt 2): 132456, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777013

RESUMO

In this study, the stabilization mechanism and digestion behavior of Pickering emulsion prepared by a combination of chitosan (CS) and TEMPO-oxidized hyaluronic acid (HA) were investigated. Conductometric titration was used to determine the degree of oxidation and carboxylate content of TEMPO-oxidized HA. The results showed that the degree of oxidation increased proportionally with increasing oxidation time, and the electrostatic and hydrogen bonding interactions with CS were significantly enhanced. The results of FTIR and TEM showed the formation of CS/oxidized HA nanoparticles (CS/oxidized-HANPs). In addition, the contact angle of CS/oxidized-HANPs is closed to 77°, thereby providing higher desorption energy at the interface. Rheological results showed that the Pickering emulsion exhibited a gel-like network structure and higher viscosity. In vitro digestion results suggested that the quercetin (Que) bioaccessibility of the CS/oxidation HANps-stabilized Pickering emulsion with an oxidation time of 20 min was better than that of the conventional emulsion prepared with CS alone. The research is expected to develop novel polysaccharide-based Pickering emulsion delivery systems for functional compounds.


Assuntos
Quitosana , Óxidos N-Cíclicos , Emulsões , Ácido Hialurônico , Nanopartículas , Oxirredução , Quitosana/química , Ácido Hialurônico/química , Emulsões/química , Nanopartículas/química , Óxidos N-Cíclicos/química , Viscosidade , Reologia , Quercetina/química
2.
Ultrason Sonochem ; 103: 106766, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38271781

RESUMO

In this study, ultrasonic-ethanol pretreatment combined with AEE was developed for oil extraction from hemp seeds. The oil yield reached a maximum of 23.32 % at 200 W ultrasonic power and 30 min ultrasonic time, at this point, the degradation rate of Δ9-THC was 83.11 %. By determining the composition of hemp seed before and after pretreatment, it was shown that ultrasonic-ethanol pretreatment reduced the protein content of the raw material. An enzyme mixture consisting of pectinase and hemicellulase (1/1/1, w/w/w) was experimentally determined to be used, and the AEE extraction conditions were optimized using the Plackett-Burman design and the Box-Behnken. The optimal conditions were determined to be pH 5, total enzyme activity of 37,800 U/g, liquid-solid ratio of 10.4 mL/g, enzyme digestion temperature of 32 °C, enzymatic time of 189 min, and oil recovery of 88.38 %. The results of confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) showed that the emulsion formed during ultrasonic ethanol pretreatment was not uniformly distributed, and the droplets appeared to be aggregated; and the irregular pores of hemp seed increased after pretreatment. The contents of Δ9-THC and CBN in the extracted oil samples were 9.58 mg/kg and 52.45 mg/kg, respectively. Compared with the oil extracted by Soxhlet extraction (SE), the oil extracted by this experimental method was of better quality and similar in fatty acid composition.


Assuntos
Cannabis , Extratos Vegetais , Cannabis/química , Ultrassom , Dronabinol/análise , Etanol/análise , Sementes/química , Água/química , Óleos de Plantas/química
3.
Sci Rep ; 13(1): 19898, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37963985

RESUMO

Peripheral arterial disease (PAD) is a prevalent subtype of atherosclerotic cardiovascular diseases. It is crucial to assess the PAD-related burden and its attributable risk factors. We use the Global Burden of Disease study 2019 database to calculate the incidence, prevalence, mortality, disability-adjusted life years (DALY), attributable risk factors and estimated annual percentage change. The disease burden of PAD grows significantly with age accompanied by prominent heterogeneity between male and female. Despite the increase in the absolute numbers of disease burden from 1990 to 2019, the global PAD-related age-standardized death rate (ASDR) and age-standardized disability-adjusted life years rate (ASDALYR) have a mild downward trend from 1990 to 2019, which negatively correlated with sociodemographic index (SDI). Smoking and high systolic blood pressure (SBP) were the primary attributable risk factors for males (ASDR: 33.4%; ASDALYR: 43.4%) and females (ASDR: 25.3%; ASDALYR: 27.6%), respectively. High fasting plasma glucose (FPG) had become the second risk factor for ASDR (males: 28.5%; females: 25.2%) and ASDALYR (males: 29.3%; females: 26.3%) with an upward tendency. Low-middle SDI regions were predicted to have the most remarkable upward trend of PAD-related burden caused by high FPG. Smoking caused more disease burden in males before 85-90 years old and females before 65-70 years old, while high FPG and high SBP caused more burden after that. The patterns of PAD-related burden and its attributable risk factors are heterogeneous across ages, genders, and SDI regions. To reduce disease burden, tailored strategies should be implemented.


Assuntos
Morte Perinatal , Doença Arterial Periférica , Feminino , Masculino , Humanos , Idoso de 80 Anos ou mais , Idoso , Carga Global da Doença , Doença Arterial Periférica/epidemiologia , Fatores de Risco , Efeitos Psicossociais da Doença , Fumar/efeitos adversos , Saúde Global
4.
Food Chem X ; 19: 100866, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37780344

RESUMO

Herein, cationic soy protein (NSPI) was synthesized by grafting Ethylenediamine (EDA) onto soy protein isolate (SPI), and protein-gallic acid (GA) complexes were formed by mixing NSPI with GA in various ratios. We assessed the structure, particle size, thermal stability, emulsifying ability, and antioxidant capacity of NSPI and complexes. Results show that grafting with EDA introduced a positive charge to SPI and resulted in a uniform particle size, and enhanced thermal stability, emulsifying ability, and antioxidant capacity. In addition, NSPI presented more amino groups and stronger interactions with GA compared to SPI. EDA and GA synergistically increased the flexibility of SPI, reducing the α-helix content and increasing the random coil content. Moreover, the interactions between SPI, NSPI, and GA were static, and hydrophobic and electrostatic between GA and SPI and NSPI, respectively. Grafting SPI with EDA improved functionality and interactions with GA, implying that NSPI-GA complexes may function as emulsifiers and antioxidants.

5.
Ultrason Sonochem ; 100: 106645, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37837709

RESUMO

Herein, ultrasound-assisted conventional covalent binding methods (alkali treatment, free radical mediation, and an enzymatic method) were used to prepare soybean protein isolate (SPI)-(-)-epigallocatechin gallate (EGCG) conjugates to investigate the enhancement effect of the ultrasound synergistic treatment. In addition, the influence of EGCG grafting on the structure and properties of SPI was evaluated via reactive group analysis, spectral analysis, surface hydrophobicity measurements, emulsification property assessment, and α-glucosidase inhibition analysis. The obtained results revealed that the enzymatic method produced the highest polyphenol grafting content among the conventional techniques. Meanwhile, ultrasound treatment increased the amount of grafted polyphenol species during the alkali treatment and free radical mediation procedure, decreased the grafting efficiency in the enzymatic method, and maximized the grafting efficiency during the alkali treatment. In addition, reactive group and spectral analyses demonstrated that EGCG formed C-N and C-S bonds with SPI and decreased the α-helix content in the protein structure, thereby increasing the molecular flexibility of SPI. It also produced hydrogen bonds and hydrophobic interactions, as demonstrated by the results of molecular docking. Furthermore, the EGCG grafting of SPI conducted under the ultrasound-assisted conditions endowed SPI with unique functional characteristics, including good emulsification and antioxidant properties and high α-glucosidase inhibitory activity, while the ultrasound-assisted alkali treatment resulted in the optimal functional properties. The results of this study provide new insights into the effective preparation of SPI-EGCG complexes with multiple functionalities, thereby expanding the scope of high-value SPI utilization.


Assuntos
Polifenóis , alfa-Glucosidases , Simulação de Acoplamento Molecular , Álcalis , Radicais Livres , Proteínas de Soja/química
6.
J Clin Med ; 12(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36983152

RESUMO

Exercise-based cardiac rehabilitation is safe and effective for chronic heart failure (CHF) patients. The present study aimed to investigate the effects of traditional Chinese exercise (TCE) on patients with CHF and the impact of exercise types and duration. Evaluation of randomized controlled trials (RCTs) of TCE in patients with CHF published since 1997 from PubMed, Embase, Web of Science, the Cochrane Library, Chongqing VIP, Wanfang Databases, and the China National Knowledge was performed. A total of 41 RCTs, including 3209 patients with CHF, were included. It showed that TCE significantly increased 6-min walk distance (6MWD) [mean difference (MD) = 72.82 m, p < 0.001] and left ventricular ejection fraction (MD = 5.09%, p < 0.001), whereas reduced B-type natriuretic peptide (BNP) (MD = -56.80 pg/mL, p < 0.001), N-terminal pro-BNP (MD = -174.94 pg/mL, p < 0.05), and Minnesota Living with Heart Failure Questionnaire scores (MD = -11.31, p < 0.001). However, no significant difference was found in the effects of TCE on peak oxygen consumption. The increase in TCE weekly duration and program duration significantly improved 6MWD (MD = 71.91 m, p < 0.001; MD = 74.11 m, p < 0.001). The combination of TCE and conventional aerobic exercise significantly improved 6MWD (MD = 19.86 m, p < 0.005). TCE improves exercise capacity, cardiac function, and quality of life in patients with CHF, which might be an optimal and available pattern of exercise-based cardiac rehabilitation.

7.
Front Cardiovasc Med ; 9: 1003233, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505369

RESUMO

Background: Calcific aortic valve disease (CAVD) was highly prevalent among developed countries and caused numerous deaths. Based on the Global Burden of Disease 2019, this study was designed to present comprehensive epidemiological information, attributable risks, and relevant factors. Methods: All data were available online via the Global Health Data Exchange (GHDx). In this study, we analyzed the global incidence, prevalence, deaths, and disability-adjusted life years (DALYs) of CAVD across different regions from 1990 to 2019. We applied the estimated annual percentage changes (EAPCs) to evaluate the change trends and their attributable risks. In addition, we explored several relevant factors. Results: From 1990 to 2019, the incidence cases, prevalence cases, CAVD-related deaths, and DALYs of CAVD gradually increased globally. However, the age-standardized death rate (ASDR) was relatively stable, and the age-standardized DALYs rate gradually declined during the past 30 years. Males and elderly individuals were more likely to suffer from CAVD. High systolic blood pressure (SBP) was the predominant attributable risk of disease burden that presented a global downward trend (death: EAPC = -0.68, 95% CI -0.77~-0.59, P < 0.001; DALYs: EAPC = -0.99, 95% CI -1.09 to -0.89, P < 0.001). Alcohol consumption (R = 0.79, P < 0.001), smoking prevalence (R = 0.75, P < 0.001), and calcium (R = 0.72, P < 0.001) showed a positive correlation with the age-standardized incidence rate (ASIR), whereas classic monsoon region (R = -0.68, P < 0.001) and mean temperature (R = -0.7, P < 0.001) showed a negative correlation with age-standardized incidence rate (ASIR). Besides, medical and healthcare resources presented a positive correlation with ASIR. Meanwhile, similar relationships were found in age-standardized prevalence rate (ASPR), ASDR, and age-standardized DALY rate (ASDALYR). Conclusion: CAVD displays widely varied spatial distribution around the world, of which high SDI regions have the highest burdens. Age is a powerful factor and hypertension a predominant attributable risk factor. Moreover, controlling blood pressure, avoiding smoking, reducing alcohol consumption, and so on, could effectively reduce the burden of CAVD.

8.
Front Cardiovasc Med ; 9: 901225, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711350

RESUMO

Background: Global and national estimates on the epidemiology of aortic aneurysms are prerequisites for disease management and policymaking. Based on the Global Burden of Disease (GBD) 2019, this study aimed to discern the global aortic aneurysm burden by systematically analyzing demographic data on mortality and exploring the attributable risks and relevant factors. Methods: The data analyzed in this study were available in the Global Health Data Exchange (GHDx) online query tool. The population in our study comprised individuals from 204 countries and territories from 1990 to 2019. The estimated annual percentage changes (EAPCs) were performed to assess the temporal trends of aortic aneurysms and their attributable risks. Spearman correlation analysis was performed to explore the relationship between the burden of aortic aneurysm and covariates. Results: Although aortic aneurysm-related deaths (82.1%) and disability-adjusted life years (DALYs) (67%) increased from 1990 to 2019, the global trend of age-standardized rate of death (ASRD) (EAPC: -1.34, 95% CI = -1.46 to -1.22, P < 0.001) and age-standardized rate of DALY (ASDALYR) (EAPC: -1.06, 95% CI = -1.17 to -0.95, P < 0.001) decreased, both of which presented age dependence and gender differences. Smoking and high systolic blood pressure (SBP) were the main attributable risks of disease burden and tend to decease globally (EAPC: -1.89, 95% CI = -2.03 to -1.89, P < 0.001; -1.31 95% CI = -1.43 to -1.19, P < 0.001, respectively). Alcohol abstinence (male: R = -0.71, P < 0.001; female: R = -0.73, P < 0.001), smoking age of initiation (male: R = -0.32, P < 0.001; female: R = -0.50, P < 0.001), physical activity (male: R = -0.50, P < 0.001; female: R = -0.55, P < 0.001), and mean temperature (R = -0.62, P < 0.001) had negative correlation with ASRD. However, cholesterol level (male: R = 0.62, P < 0.001; female: R = 0.39, P < 0.001), body mass index (BMI) (male: R = 0.30, P < 0.001; female R = -0.01, P > 0.05), and alcohol consumption (male: R = 0.46, P < 0.001; female: R = 0.42, P < 0.001) had a positive correlation with ASRM. Besides, standard of living and medical resources positively related to burden of aortic aneurysm. Conclusion: In this study, a decreasing trend of aortic aneurysm burden was found globally, especially in advanced regions. Aged men who smoke and women who have hypertension should pay close attention to, particularly in deprived economic groups, and many approaches can be performed to reduce the burden of aortic aneurysms.

9.
Syst Biol ; 61(1): 90-106, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22139466

RESUMO

Highly accurate estimation of phylogenetic trees for large data sets is difficult, in part because multiple sequence alignments must be accurate for phylogeny estimation methods to be accurate. Coestimation of alignments and trees has been attempted but currently only SATé estimates reasonably accurate trees and alignments for large data sets in practical time frames (Liu K., Raghavan S., Nelesen S., Linder C.R., Warnow T. 2009b. Rapid and accurate large-scale coestimation of sequence alignments and phylogenetic trees. Science. 324:1561-1564). Here, we present a modification to the original SATé algorithm that improves upon SATé (which we now call SATé-I) in terms of speed and of phylogenetic and alignment accuracy. SATé-II uses a different divide-and-conquer strategy than SATé-I and so produces smaller more closely related subsets than SATé-I; as a result, SATé-II produces more accurate alignments and trees, can analyze larger data sets, and runs more efficiently than SATé-I. Generally, SATé is a metamethod that takes an existing multiple sequence alignment method as an input parameter and boosts the quality of that alignment method. SATé-II-boosted alignment methods are significantly more accurate than their unboosted versions, and trees based upon these improved alignments are more accurate than trees based upon the original alignments. Because SATé-I used maximum likelihood (ML) methods that treat gaps as missing data to estimate trees and because we found a correlation between the quality of tree/alignment pairs and ML scores, we explored the degree to which SATé's performance depends on using ML with gaps treated as missing data to determine the best tree/alignment pair. We present two lines of evidence that using ML with gaps treated as missing data to optimize the alignment and tree produces very poor results. First, we show that the optimization problem where a set of unaligned DNA sequences is given and the output is the tree and alignment of those sequences that maximize likelihood under the Jukes-Cantor model is uninformative in the worst possible sense. For all inputs, all trees optimize the likelihood score. Second, we show that a greedy heuristic that uses GTR+Gamma ML to optimize the alignment and the tree can produce very poor alignments and trees. Therefore, the excellent performance of SATé-II and SATé-I is not because ML is used as an optimization criterion for choosing the best tree/alignment pair but rather due to the particular divide-and-conquer realignment techniques employed.


Assuntos
Filogenia , Alinhamento de Sequência/métodos , Software , Algoritmos , Automação , Simulação por Computador , DNA , Evolução Molecular , Funções Verossimilhança
10.
Mol Biol Evol ; 24(8): 1667-77, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17470435

RESUMO

A central goal of computational biology is the prediction of phenotype from DNA and protein sequence data. Recent models of sequence change use in silico prediction systems to incorporate the effects of phenotype on evolutionary rates. These models have been designed for analyzing sequence data from different species and have been accompanied by statistical techniques for estimating model parameters when the incorporation of phenotype induces dependent change among sequence positions. A difficulty with these efforts to link phenotype and interspecific evolution is that evolution occurs within populations, and parameters of interspecific models should have population genetic interpretations. We show, with two examples, how population genetic interpretations can be assigned to evolutionary models. The first example considers the impact of RNA secondary structure on sequence change, and the second reflects the tendency for protein tertiary structure to influence nonsynonymous substitution rates. We argue that statistical fit to data should not be the sole criterion for assessing models of sequence change. A good interspecific model should also yield a clear and biologically plausible population genetic interpretation.


Assuntos
Anexina A5/genética , Genética Populacional , RNA/genética , Animais , Biologia Computacional , Simulação por Computador , Evolução Molecular , Variação Genética , Funções Verossimilhança , Camundongos , Modelos Biológicos , Modelos Genéticos , Conformação de Ácido Nucleico , Fenótipo , Filogenia , RNA/química , Ratos , Seleção Genética
11.
J Mol Evol ; 62(6): 682-92, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16752209

RESUMO

Widely used models of protein evolution ignore protein structure. Therefore, these models do not predict spatial clustering of amino acid replacements with respect to tertiary structure. One formal and biologically implausible possibility is that there is no tendency for amino acid replacements to be spatially clustered during evolution. An alternative to this is that amino acid replacements are spatially clustered and this spatial clustering can be fully explained by a tendency for similar rates of amino acid replacement at sites that are nearby in protein tertiary structure. A third possibility is that the amount of clustering exceeds that which can be explained solely on the basis of independently evolving protein sites with spatially clustered replacement rates. We introduce two simple and not very parametric hypothesis tests that help distinguish these three possibilities. We then apply these tests to 273 homologous protein families. The null hypothesis of no spatial clustering is rejected for 102 of 273 families. The explanation of spatially clustered rates but independent change among sites is rejected for 43 families. These findings need to be reconciled with the common practice of basing evolutionary inferences on models that assume independent change among sites.


Assuntos
Substituição de Aminoácidos , Evolução Molecular , Análise por Conglomerados , Estrutura Terciária de Proteína , Estatísticas não Paramétricas
12.
Mol Biol Evol ; 23(8): 1525-37, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16720696

RESUMO

Although probabilistic models of genotype (e.g., DNA sequence) evolution have been greatly elaborated, less attention has been paid to the effect of phenotype on the evolution of the genotype. Here we propose an evolutionary model and a Bayesian inference procedure that are aimed at filling this gap. In the model, RNA secondary structure links genotype and phenotype by treating the approximate free energy of a sequence folded into a secondary structure as a surrogate for fitness. The underlying idea is that a nucleotide substitution resulting in a more stable secondary structure should have a higher rate than a substitution that yields a less stable secondary structure. This free energy approach incorporates evolutionary dependencies among sequence positions beyond those that are reflected simply by jointly modeling change at paired positions in an RNA helix. Although there is not a formal requirement with this approach that secondary structure be known and nearly invariant over evolutionary time, computational considerations make these assumptions attractive and they have been adopted in a software program that permits statistical analysis of multiple homologous sequences that are related via a known phylogenetic tree topology. Analyses of 5S ribosomal RNA sequences are presented to illustrate and quantify the strong impact that RNA secondary structure has on substitution rates. Analyses on simulated sequences show that the new inference procedure has reasonable statistical properties. Potential applications of this procedure, including improved ancestral sequence inference and location of functionally interesting sites, are discussed.


Assuntos
Evolução Molecular , Conformação de Ácido Nucleico , Filogenia , RNA Ribossômico/genética , RNA/genética , Animais , Simulação por Computador , Cadeias de Markov , RNA/química , RNA Ribossômico/química , Análise de Sequência de RNA
13.
Genetics ; 163(2): 723-33, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12618409

RESUMO

Genes that have undergone positive or diversifying selection are likely to be associated with adaptive divergence between species. One indicator of adaptive selection at the molecular level is an excess of amino acid replacement fixed differences per replacement site relative to the number of synonymous fixed differences per synonymous site (omega = K(a)/K(s)). We used an evolutionary expressed sequence tag (EST) approach to estimate the distribution of omega among 304 orthologous loci between Arabidopsis thaliana and A. lyrata to identify genes potentially involved in the adaptive divergence between these two Brassicaceae species. We find that 14 of 304 genes (approximately 5%) have an estimated omega > 1 and are candidates for genes with increased selection intensities. Molecular population genetic analyses of 6 of these rapidly evolving protein loci indicate that, despite their high levels of between-species nonsynonymous divergence, these genes do not have elevated levels of intraspecific replacement polymorphisms compared to previously studied genes. A hierarchical Bayesian analysis of protein-coding region evolution within and between species also indicates that the selection intensities of these genes are elevated compared to previously studied A. thaliana nuclear loci.


Assuntos
Arabidopsis/genética , Evolução Molecular , Proteínas/genética , Seleção Genética , Etiquetas de Sequências Expressas , Dados de Sequência Molecular
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