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










Base de dados
Intervalo de ano de publicação
1.
Eur J Pharm Biopharm ; 198: 114269, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38527635

RESUMO

Sucrose esters (SEs) have great potential in the field of nucleic acid delivery due to their unique physical and chemical properties and good biosafety. However, the mechanism of the effect of SEs structure on delivery efficiency has not been studied. The liposomes containing peptide lipids and SEs were constructed, and the effects of SEs on the interaction between the liposomes and DNA were studied. The addition of SEs affects the binding rate of liposomes to DNA, and the binding rate gradually decreases with the increase of SEs' carbon chain length. SEs also affect the binding site and affinity of liposomes to DNA, promoting the aggregation of lipids to form liposomes, where DNA wraps around or compresses inside the liposomes, allowing it to compress DNA without damaging the DNA structure. COL-6, which is composed of sucrose laurate, exhibits the optimal affinity for DNA, and SE promotes the formation of ordered membrane structure and enhances membrane stability, so that COL-6 exhibits a balance between rigidity and flexibility, and thus exhibits the highest delivery efficiency of DNA among these formulations. This work provides theoretical foundations for the application of SE in gene delivery and guides for the rational design of delivery systems.


Assuntos
Ésteres , Lipossomos , Lipossomos/química , Ésteres/química , DNA/metabolismo , Sacarose/química , Lipídeos/química
2.
Sheng Wu Gong Cheng Xue Bao ; 39(12): 4874-4886, 2023 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-38147988

RESUMO

Mycoplasma capricolum subsp. capripneumoniae (Mccp) is the cause of contagious caprine pleuropneumonia (CCPP) in goats. Inactivated vaccines and capsular polysaccharide (CPS) indirect hemagglutination reagents are available for prevention and serological detection, but high culture costs and complex antigen quantification have been plagued by production staff. In order to solve these problems in production practice, a sugar fermentation medium with an initial pH value of 7.8, which could improve the production of two antigens simultaneously, was screened out by changing the initial pH value based on previous Mccp metabolomics analysis. Since phenol red can be identified by UV absorption spectrum and cetyltrimethylammonium bromide (CTAB) can bind to anionic capsular polysaccharide, a UV spectrum measurement method for analyzing the culture stage reached by Mccp and a CTAB precipitation test for relative quantification of capsular polysaccharide antigen content in the fermentation broth were established. The UV spectrum observation method can guide the production of Mccp according to the growth curve of Mccp, which greatly reduces the monitoring time of the traditional CCU method and improves the accuracy of the original eye-observation method. The established CTAB precipitation test can complete the monitoring of CPS content within 5 hours, which greatly reduces the time required compared with the traditional differential technique, and its accuracy was verified by the phenol-sulfuric acid method. The optimized culture medium and the two correlation comparison methods established in this study can effectively reduce the production cost of Mccp and improve the production efficiency. The two assays have been used in the research at our laboratory, which provides experimental data for further improvement of the production process of CCPP inactivated vaccine and capsular polysaccharide as well as rapid quantification.


Assuntos
Cabras , Mycoplasma , Humanos , Animais , Cetrimônio , Polissacarídeos
3.
Physiol Plant ; 175(5): e14016, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37882258

RESUMO

Iris lactea var. chinensis (Fisch.) Koidz has a unique floral fragrance that differs from that of other Iris spp.; however, its characteristic aroma composition remains unknown. This study aimed to identify the floral fragrance components of I. lactea var. chinensis during different flowering stages using headspace solid-phase microextraction in conjunction with gas chromatography mass spectrometry, electronic nose, and sensory evaluation. During the three flowering phases (bud stage, bloom stage, and decay stage), 70 volatile organic compounds (VOCs), including 13 aldehydes, 13 esters, 11 alcohols, 10 alkanes, 8 ketones, 7 terpenes, 7 benzenoids, and 1 nitrogenous compound, were identified. According to principal component analysis, the primary VOCs were (-)-pinene, ß-irone, methyl heptenone, phenylethanol, hexanol, and 2-pinene. A comparison of the differential VOCs across the different flowering stages using orthogonal partial least squares discriminant analysis and hierarchical clustering analysis revealed that 3-carene appeared only in the bud stage, whereas hexanol, ethyl caprate, ethyl caproate, linalool, (-)-pinene, and 2-pinene appeared or were present at significantly increased levels during the bloom stage. The phenylethanol, methyl heptenone, 3-methylheptane, and ß-irone reached a peak in the decay stage. The odor activity value and sensory evaluation suggested that "spicy" is the most typical odor of I. lactea var. chinensis, mainly due to 2-methoxy-3-sec-butylpyrazine, which is rare in floral fragrances.


Assuntos
Iris (Planta) , Álcool Feniletílico , Compostos Orgânicos Voláteis , Iris (Planta)/química , Odorantes/análise , Norisoprenoides , Hexanóis
4.
Int J Biol Macromol ; 253(Pt 3): 126867, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37730005

RESUMO

A crucial aspect in achieving sustainable development of biomass materials is the modification of renewable polysaccharides to create various high-value functional materials. In this paper, bagasse xylan (BX) was used as a raw material to introduce benzyl methacrylate (BMA) through graft copolymerization reaction to generate the intermediate product BX-g-BMA. Subsequently, the target product (CA-BX-g-BMA) was synthesized by catalytic esterification of BX-g-BMA with citric acid (CA) in AmimCl ionic liquid. Meanwhile, the characterization and bioactivity studies of CA-BX-g-BMA were carried out. The graft copolymerization and esterification reactions induced significant changes in the morphological structure of BX and obviously improved its thermal stability and crystallinity. The application of density functional theory (DFT), molecular electrostatic potential (MEP) and molecular docking has revealed that CA-BX-g-BMA possesses multiple active sites, strong biological activity and a strong binding affinity to 6RCF tumor protein with a binding energy of -32.26 kJ/mol. The in vitro antitumor activity of this novel derivative was tested by MTT assay, and the results showed that CA-BX-g-BMA was non-toxic to normal cells and inhibited MDA-MB-231 (breast cancer cells) by up to 32.16 % ± 4.89 %, which is approximately 11 times higher than that of BX. The exploration of these properties is essential to promote future multidisciplinary applications of BX derivatives.


Assuntos
Celulose , Xilanos , Xilanos/farmacologia , Xilanos/química , Esterificação , Simulação de Acoplamento Molecular , Celulose/química , Ácido Cítrico
5.
Food Chem Toxicol ; 179: 113978, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37532171

RESUMO

3-monochloropropane-1,2-diol esters (3-MCPDEs) and glycidyl esters (GEs) are food contaminants and have arisen continuous attention due to their toxicity, especially towards infants. Current risk assessment of these contaminants was mostly employing deterministic approaches, lacking quantitative characterization of the likelihood, incidence, or severity of the risks involved. Herein, 3-MCPDE and GE levels in 46 representative infant formulas (IFs) from Chinese market were determined by GC-MS/MS. Then, combining the occurrence data and consumption data from China National Food Consumption Survey, the Monte Carlo simulation-based probabilistic model for risk assessment of 3-MCPDEs and GEs in IFs from Chinese market was established. The results showed that all P90 (90th percentiles) hazard quotient values were below 1, demonstrating 3-MCPDEs didn't pose health risks to most populations aged 0-36 months old. However, for 0-12 months old groups, P10 (10th percentiles) margin of exposure values were all below 25000, indicating GEs may pose potential risks to 10% of this group. Uncertainty analysis revealed that the probabilistic model had considered uncertainties of model input and distribution, and realized refined assessment. This study is the first report on probabilistic assessment of 3-MCPDEs and GEs in IFs, which also provided references for the formulation of related regulatory limits in China.


Assuntos
Contaminação de Alimentos , alfa-Cloridrina , Lactente , Humanos , Recém-Nascido , Pré-Escolar , Contaminação de Alimentos/análise , Fórmulas Infantis/análise , Ésteres , Espectrometria de Massas em Tandem , Método de Monte Carlo , alfa-Cloridrina/análise , Medição de Risco
6.
Bioresour Technol ; 386: 129506, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37468005

RESUMO

For low yield in dark fermentation (DF), in this study, the carbonized humic acid (CHA) was produced and added to DF for enhancing biohydrogen (bioH2) yield at mesophilic condition. The highest bioH2 yield was 151.08 mL/g glucose with the addition of CHA at 80 mg/L, which was 35.27% and 16.53% higher than those of 0 mg/L CHA and 80 mg/L mineral humic acid (MHA) groups, respectively. Electrons preferentially conducted via the butyrate pathway due to CHA amendments, which corresponded to the prediction of relevant functional genes. Furthermore, CHA possessed distinctive advantages over MHA, which acted as an electron shuttle to facilitate electron transfer, released metal ions as an essential signal mediator and favored the reduction of ferredoxin, obtaining more H2. The use of CHA in the field of H2-DF depicted the high-value utilization and industrial chain extension of MHA.


Assuntos
Substâncias Húmicas , Hidrogênio , Hidrogênio/metabolismo , Fermentação , Reatores Biológicos , Transporte de Elétrons
7.
Bioresour Technol ; 385: 129466, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37429558

RESUMO

Generally, dark fermentation (DF) of hydrogen (H2) synthesis has low H2 production from industrial-scale plants. In this study, campus greening wastes-ginkgo leaves were used to produce molten salt-modified biochar (MSBC) and nitrogen (N2)-atmosphere BC (NBC) in molten salt and N2 environment at 800 °C, respectively. MSBC showed excellent properties including high specific surface area and electron transfer ability. After supplementation with MSBC, H2 yield rose by 32.4% compared to the control group without carbon material. Electrochemical analysis revealed MSBC improved the electrochemical properties of sludge. Furthermore, MSBC optimized the microbial community structure and increased the relative abundance of dominant microbes, thus promoting H2 production. This work provides a deep understanding of two carbons that play vital roles in increasing microbial biomass, supplementing trace element and favoring electron transfer in DF reactions. Salt recovery achieved 93.57% in molten salt carbonization, which has sustainability compared with N2-atmosphere pyrolysis.


Assuntos
Carbono , Carvão Vegetal , Carvão Vegetal/química , Fermentação , Cloreto de Sódio , Hidrogênio
8.
Environ Sci Pollut Res Int ; 30(37): 87215-87227, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37420156

RESUMO

Low biological hydrogen (bioH2) production due to non-optimal metabolic pathways occurs frequently. In this work, magnetic nitrogen-doped activated carbon (MNAC) was prepared and added into the inoculated sludge with glucose as substrate to enhance hydrogen (H2) yield by mesophilic dark fermentation (DF). The highest H2 yield appeared in 400 mg/L AC (252.8 mL/g glucose) and 600 mg/L MNAC group (304.8 mL/g glucose), which were 26.02% and 51.94% higher than that of 0 mg/L MNAC group (200.6 mL/g glucose). The addition of MNAC allowed for efficient enrichment of Firmicutes and Clostridium-sensu-stricto-1, accelerating the metabolic pathway shifted towards butyrate type. The Fe ions released by MNAC facilitated electron transfer and favored the reduction of ferredoxin (Fd), thereby obtaining more bioH2. Finally, the generation of [Fe-Fe] hydrogenase and cellular components of H2-producing microbes (HPM) during homeostasis was discussed to understand on the use of MNAC in DF system.


Assuntos
Carvão Vegetal , Hidrogênio , Fermentação , Hidrogênio/metabolismo , Glucose , Fenômenos Magnéticos , Reatores Biológicos
9.
Bioresour Technol ; 385: 129371, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37348568

RESUMO

Dark fermentation (DF) for hydrogen (H2) evolution is often limited to industrial application due to its low H2 yield. In this work, hydrothermal carbon microspheres (HCM) and iron modified HCM (Fe-HCM) were prepared by hydrothermal process using waste corn cob. Subsequently, HCM and Fe-HCM were used in DF for more H2. The highest H2 yields amended with HCM and Fe-HCM at 600 mg/L were achieved to be 119 and 154 mL/g glucose (0.87 and 1.2 mol H2/mol glucose), respectively, being 24% and 59% higher than that of control yield. Soluble metabolites revealed HCM and Fe-HCM promoted butyric acid-based DF. Microbial composition depicted that HCM and Fe-HCM improved the abundance level of Firmicutes from 35% to 41% and 56%, while the abundance level of Clostridium_sensu_stricto_1 rose from 25% to 38% and 51%, respectively. This provides valuable guidance for hydrothermal carbon used in biofuel production.


Assuntos
Carbono , Ferro , Microesferas , Fermentação , Hidrogênio/metabolismo , Glucose , Reatores Biológicos
10.
J Environ Manage ; 340: 117975, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37084648

RESUMO

Several reports have shown that pharmaceuticals and personal care products (PPCPs) have some negative effects on anaerobic digestion (AD), yet there are no convenient and efficient strategies for mitigating the adverse influences. The typical PPCPs of carbamazepine have a strong negative effect on lactic acid AD process. Therefore, in this work, novel lanthanum-iron oxide (LaFeO3) nanoparticles (NPs) were used for adsorption and bioaugmentation to weak the negative effects of carbamazepine. The adsorption removal of carbamazepine increased from 0 to 44.30% as the dosage of LaFeO3 NPs was increased from 0 to 200 mg/L, providing the necessary prerequisites for bioaugmentation. Adsorption reduced the probability of direct contact between carbamazepine and anaerobes, partly alleviating the inhibition of carbamazepine on microbes. The highest methane (CH4) yield induced by LaFeO3 NPs (25 mg/L) was 226.09 mL/g lactic acid, increasing by 30.06% compared to the control yield with a recovery to 89.09% of the normal CH4 yield. Despite the ability of LaFeO3 NPs to restore normal AD performance, the biodegradation rate of carbamazepine remained below 10% due to its anti-biodegradability. Bioaugmentation was primarily reflected in the enhanced bioavailability of dissolved organic matter, while the intracellular LaFeO3 NPs promoted coenzyme F420 activity through binding to humic substances. Under the mediation of LaFeO3, a direct interspecies electron transfer system with Longilinea and Methanosaeta as functional bacteria was successfully constructed and the corresponding electron transfer rate was accelerated from 0.021 s-1 to 0.033 s-1. LaFeO3 NPs eventually recovered AD performance under carbamazepine stress in an adsorption and bioaugmentation manner.


Assuntos
Nanopartículas , Esgotos , Anaerobiose , Lantânio , Adsorção , Nanopartículas/química , Nanopartículas Magnéticas de Óxido de Ferro , Metano , Reatores Biológicos
11.
ACS Omega ; 7(45): 41594-41605, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36406540

RESUMO

The positive effects of metal oxide nanoparticles (NPs) on dark fermentation (DF) for biohydrogen synthesis have been increased, and the mechanism still needs to be further revealed. In this study, nickel-cobalt oxide (NiCo2O4) NPs were prepared to increase H2 yield via DF. The highest (259.67 mL/g glucose) and the lowest (188.14 mL/g glucose) yields were achieved at 400 and 800 mg/L NiCo2O4 NPs added, respectively, with their corresponding 33.97% increase and 2.93% decrease compared with the control yield (193.82 mL/g glucose). Meanwhile, the microbial community further confirmed that NiCo2O4 NPs increased the abundance of the dominant H2-producing Clostridium sensu stricto 1 by 23.05%. The gene prediction also showed that NiCo2O4 NPs increased the abundance of genes encoding the rate-limiting enzyme pyruvate kinase in glycolysis, thus increasing the substrate conversion. Moreover, the gene abundance of key enzymes directly related to H2 evolution was also increased at different levels.

12.
Front Psychol ; 13: 915235, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248461

RESUMO

Based on the life history theory and broadening construction theory, the study aimed to investigate the influence of Machiavellianism on the learning-related subjective well-being and the underlying mechanism, 582 Chinese senior high school students (16.8 ± 0.9 years old) including 289 girls (48.3%) and 310 boys were recruited to participate in this study, and they anonymously filled out questionnaires regarding Machiavellianism, learning-related subjective well-being, gratitude, and subjective family economic level. The results showed that: (1) a higher level of Machiavellianism was associated with a lower level of learning-related subjective well-being; (2) gratitude partially mediated the relationship between Machiavellianism and learning-related subjective well-being; (3) subjective family economic level moderated the links between Machiavellianism and learning-related subjective well-being, and between gratitude and learning-related subjective well-being. This study explained how and when Machiavellianism affected Chinese senior high school students' learning-related subjective well-being and provided a deeper understanding of the relationship between Machiavellianism and learning-related subjective well-being.

13.
Front Aging Neurosci ; 14: 936027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105909

RESUMO

Background: Tai Chi can show improvement in balance and motor ability of elderly patients with PD. However, there were few reports on differences in outcomes associated with different types of Tai Chi on improving exercise capacity in elderly patients with PD. We compared the improvement of motor function in Parkinson's patients with different types of Tai Chi, for finding an optimal intervention. Methods: The following databases were searched from the beginning of the establishment of each database to 10 January 2022: PubMed, EMBASE, The Cochrane Library, CNKI, Wanfang Database, and VIP Database. Randomized controlled trials incorporating different types of Tai Chi for PD were included. The outcome measures were UPDRSIII and BBS. NMA was conducted using Stata 15.0 based on a frequentist framework. Results: A total of twenty trials were eligible, including 996 participants. In conventional meta-analysis, as for the UPDRSIII scale, 24-form simplified Tai Chi (SMD = -1.272, 95% CI [-2.036, -0.508], P < 0.05, I2 > 50%), Tai Chi exercise program (SMD = -0.839, 95% CI [-1.828, 0.151], P > 0.05, I2 > 50%), 8-form simplified Yang style Tai Chi (SMD = -0.325, 95% CI [-1.362, 0.713], P > 0.05, I2 > 50%), and 8-form simplified Chen style Tai Chi (SMD = -0.28, 95% CI [-0.97, 0.42], P > 0.05, I2 > 50%) were statistically more efficient than the control group. For BBS outcome, 24-form simplified Tai Chi (MD = 3.979, 95% CI [3.364, 4.595], P < 0.05, I2 <50%), Tai Chi exercise program (MD = 5.00, 95% CI [2.07, 7.93], P > 0.05, I2 > 50%), and 8-form simplified Chen style Tai Chi (MD = 1.25, 95% CI [0.52, 1.98], P < 0.05, I2 > 50%) were better than the control group. In the network meta-analysis, the results of UPDRSIII were as follows: 24-form > TCEP > 8-form YS > 8-form CS > control. The ranking probability of BBS was as follows: TCEP > 24-form > 8-form CS > control. Conclusion: Among the four treatments studied, 24-form Tai Chi and Tai Chi exercise programs have shown better efficacy than other types. Our study provides new insights into exercise therapy for PD and may contribute to the formulation of a clinical exercise prescription. Systematic review registration: Identifier: CRD42021285005.

14.
Front Psychol ; 13: 983844, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36176792

RESUMO

A number of existing researches agree that digitalization would facility firms to launch ambidextrous innovations. Digitalization is not only about technological change, but more importantly, the reshaping of the firms' knowledge structure and routines to percept and integrate knowledge. Thus, some researchers suggest that whether firms could benefit from digitalization varies across firms and industries, since innovation in different firms and industries relies on differentiated level of cognitive and reasoning of knowledge. However, existing studies mainly focus on exploring the firm-level differences, and leave the industry-level difference underdeveloped. In response, this study integrates knowledge-based view to examine how a firm's digitalization affects ambidextrous innovation, and further explore the conjoint effect of industrial knowledge bases-the knowledge base of the industry the firm is located in-on the relationship between firm digitalization level and ambidextrous innovation. This study uses Python to conduct text mining of firms' annual reports, and obtains data of 394 listed companies from the year 2014 to 2020. The empirical results show that digitalization level has positive effect on both exploratory innovation and exploitative innovation, and the effect on exploitative innovation is stronger than on exploratory innovation. Moreover, the moderating effect of industrial knowledge base is significant on "digitalization-exploratory innovation" but not on "digitalization-exploitative innovation" relationship. By doing so, this study refines the research on the relationship between digitalization and firm innovation, and confirms that the usage of digitalization may lead to achieve an ambidextrous situation. This study also provides a theoretical basis for industrial differences of the effectiveness of digitalization, suggesting firms considering industrial characteristics to implement digitalization-assisted innovation practices.

15.
Curr Psychol ; : 1-13, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36065326

RESUMO

Personality is distal vulnerability of negative emotions and vital to mental health. Dark Triad was significantly correlated with negative emotions, whereas the mechanisms beneath the relationships were less clear. Based on life history strategy theory (LHS) and cognitive vulnerability-transactional stress model, the study explored the relationships between Dark Triad and negative emotions and investigated the roles of negative coping style and state boredom in the relationships aforementioned during the strict period of COVID-19 lockdown in China. 464 participants (M age = 36.78 years; SD = 10.53) finished a package of measurements online including Depression Anxiety and Stress Scale (DASS-21), Short Dark Triad (SD3), Multidimensional State Boredom Scale (MSBS), and Simplified Coping Style Questionnaire (SCSQ). The results showed there were positive relationships between Dark Triad and depression, anxiety and stress. Moreover, the relationships between Dark Triad and negative emotions were sequentially mediated by negative coping style and state boredom. The present study offered fascinating perspectives in the relationships between Dark Triad and negative emotions, and revealed how Dark Triad affected depression, anxiety and stress during the initial phase of COVID-19 pandemic and strict lockdown among Chinese population. The present results may provide important implications for the prevention and intervention of depression, anxiety and stress during COVID-19 pandemic and lockdown. Specifically, the intervention strategies that focus on reducing Dark Triad, negative coping and boredom may help offset occurrence of negative emotional states.

16.
Front Cardiovasc Med ; 9: 936018, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046185

RESUMO

Background: As a therapy to prevent and treat hypertension, exercise is widely used in clinical practice. But due to the lack of documentary evidence, Baduanjin as a relaxed and convenient mode of exercise is not currently recommended by professional health organizations to treat hypertension. The purpose of this article is to examine the efficacy of Baduanjin as an antihypertensive exercise therapy. Methods: Our systematic retrieved of the entire relevant literatures in 12 databases. Finally, 28 eligible trials involving Baduanjin intervention in hypertension were included. After the quality assessment and bias risk assessment of the included trials, we analyzed the blood pressure values before and after the intervention, and performed meta-analysis on the random effect results. In order to explore the factors influencing the decrease of blood pressure, we also performed a subgroup analysis of the results. Results: Participants (n = 2121) were adults (61.74 ± 5.85years of age, mean ± SD), with baseline blood pressure (systolic blood pressure (SBP) = 150.7 ± 9.2 mmHg, diastolic blood pressure (DBP) = 93.2 ± 8.8 mmHg). Baduanjin was practiced 7.5 ± 3.8 sessions / week for 28.2 ± 12.8 min /session for 16.7 ± 9.2 weeks. Overall, Baduanjin resulted in SBP (-9.3 mmHg, d = -1.49, 95%CI: -1.73 to -1.13) and DBP (-6.3 mmHg, d = -1.20, 95%CI: -1.51 to -0.88) vs. the control group (p < 0.001). After a subgroup analysis of age, we found that SBP heterogeneity was significantly reduced in the elderly group. Conclusion: Our results indicate that Baduanjin can effectively reduce blood pressure (i.e., 9.3 mmHg and 6.3 mmHg of SBP and DBP reductions, respectively), and reduce the incidence rate of cardiovascular disease in hypertensive patients. In addition, we will be more likely to recommend that the elderly exercise Baduanjin.

17.
Molecules ; 27(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36144706

RESUMO

As a biocompatible biomaterial, bagasse xylan (BX) has been widely used in the biomedical field. The low biological activity of andrographolide (AD) restricts its development, so AD with certain anticancer activity is introduced. We use chemical modification methods such as grafting and esterification to improve the biological activity and make a novel anticancer nanomaterial. On the basis of the esterification of a mixture of BX and AD with folic acid (FA), a novel anticancer nanoderivative of bagasse xylan/andrographolide folate-g-dimethylaminoethyl methacrylate (DMAEMA)/diethylene glycol dimethacrylate (DEGDMA) nanoparticles (FA-BX/AD-g-DMAEMA/DEGDMA NPs) was synthesized by introducing DMAEMA and DEGDMA monomers through a graft copolymerization and nanoprecipitation method. The effects of reaction temperature, reaction time, the initiator concentration and the mass ratio of FA-BX/AD to mixed monomers on the grafting rate (GR) were investigated. The structure of the obtained product was characterized by FTIR, SEM, XRD and DTG. Further, molecular docking and MTT assays were performed to understand the possible docking sites with the target proteins and the anticancer activity of the product. The results showed that the GR of the obtained product was 79% under the conditions of the initiator concentration 55 mmol/L, m (FA-BX/AD):m (mixed monomer) = 1:2, reaction temperature 50 °C and reaction time 5 h. The inhibition rate of FA-BX/AD-g-DMAEMA/DEGDMA NPs on human lung cancer cells (NCI-H460) can reach 39.77 ± 5.62%, which is about 7.6 times higher than that of BX. Therefore, this material may have potential applications in the development of anticancer drug or carriers and functional materials.


Assuntos
Antineoplásicos , Nanopartículas , Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Celulose , Diterpenos , Portadores de Fármacos , Etilenoglicóis , Ácido Fólico/química , Humanos , Metacrilatos/química , Simulação de Acoplamento Molecular , Nanopartículas/química , Xilanos/farmacologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-35954881

RESUMO

The study explored sex differences in traditional school bullying perpetration and victimization among Chinese adolescents and the effects of Machiavellianism and school climate. Data were collected from 727 adolescents (M = 16.8 years, SD = 0.9) who completed the Olweus Bully/Victim Questionnaire, Kiddie Machiavellian Scale, and School Climate Perception Questionnaire. Results showed: (1) boys were more likely to bully others and be bullied; (2) both Machiavellianism and school climate partially mediated sex differences in school bullying perpetration and victimization; (3) the chain-mediating effect of Machiavellianism and school climate on sex differences in bullying perpetration and victimization was significant. These results provide insight into the sex differences in Chinese traditional school bullying perpetration and victimization. The implications are interpreted and discussed.


Assuntos
Bullying , Vítimas de Crime , Adolescente , Feminino , Humanos , Masculino , Instituições Acadêmicas , Caracteres Sexuais , Inquéritos e Questionários
19.
Polymers (Basel) ; 14(16)2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36015689

RESUMO

In the in-depth research that has been conducted on nanometer biomaterials, how to use the biomass resources with high activity and low toxicity to prepare nanomaterials for biomedical applications has attracted much attention. To realize efficient and comprehensive utilization of biomass, bagasse xylan/andrographolide (BX/AD) was ued as a raw material and glycyrrhetinic acid (GA) as an esterification agent to synthesize bagasse xylan/andrographolide esterified derivative (GA-BX/AD). Then, the bagasse xylan/andrographolide grafted and esterified derivative (GA-BX/AD-g-IA) was synthesized by the graft crosslinking reactions using itaconic acid (IA) as graft monomer. The better synthesis conditions were optimized by single factor experiments, the degree of esterification substitution (DS) was 0.43, and the grafting rate (G) of the product reached 42%. The structure and properties of the product were characterized by FTIR, XRD, DTG, SEM, and 1H NMR. The results showed that the product morphology was significantly changed, and the nanoparticles were spherical with a particle size of about 100 nm. The anti-cancer activity of the product was measured. The molecular docking simulations revealed that the product had good docking activity with human glucocorticoid protein (6CFN) with a binding free energy of 14.38 kcal/mol. The MTT assay showed that the product had a strong inhibitory effect on the growth of human liver cancer cells (BEL-7407) and gastric cancer cells (MGC80-3), with inhibition ratio of 38.41 ± 5.32% and 32.69 ± 4.87%. Therefore, this nanomaterial is expected to be applied to the development and utilization of drug carriers and functional materials.

20.
Materials (Basel) ; 15(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35897598

RESUMO

Biomass materials are high-quality raw materials for the preparation of natural, green and highly active functional materials due to their rich active groups, wide sources and low toxicity. Bagasse xylan (BX) and resveratrol (Res) were used as raw materials to introduce ethylene glycol dimethacrylate (EGDMA) via grafting reaction to obtain the intermediate product BX/Res-g-EGDMA. The intermediate was esterified with 3-carboxyphenylboronic acid (3-CBA) to obtain the target product 3-CBA-BX/Res-g-EGDMA. The BX/Res-composite-modified nanoderivative with antitumor activity was synthesized with the nanoprecipitation method. The effects of the reaction conditions on the grafting rate (G) of BX/Res-g-EGDMA and the degree of substitution (DS) of 3-CBA-BX/Res-g-EGDMA were investigated using single-factor experiments. The results showed that under the optimized process conditions, G and DS reached 142.44% and 0.485, respectively. The product was characterized with FTIR, XRD, TG-FTC, 1H NMR and SEM, and its anticancer activity was simulated and tested. The results showed that 3-CBA-BX/Res-g-EGDMA had a spherical structure with an average particle size of about 100 nm and that its crystalline structure and thermal stability were different from those of the raw materials. In addition, 3-CBA-BX/Res-g-EGDMA showed the best docking activity with 2HE7 with a binding free energy of -6.3 kJ/mol. The inhibition rate of 3-CBA-BX/Res-g-EGDMA on MGC80-3 (gastric cancer cells) reached 36.71 ± 4.93%, which was 18 times higher than that of BX. Therefore, this material could be a potential candidate for biomedical applications.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...