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排序方式: 共有1374条查询结果,搜索用时 15 毫秒
31.
Bioactive glasses (BGs) have been used for bone formation and bone repair processes in recent years. This study investigated the titanium substitution effect on 58S BGs (Ti-BGs) 60SiO2-(36 − X)CaO-4P2O5-XTiO2 (X = 0, 3, and 5 mol.%) prepared by the sol-gel technique, and the main goal was to find the optimum amount of titanium in Ti-BGs. Synthesized BGs, which were investigated after immersion in simulated body fluid (SBF), were tested by X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy. Moreover alkaline phosphate (ALP) activity, 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and antibacterial studies were employed to investigate the biological properties of Ti-BGs. According to the FTIR and XRD test results, hydroxyapatite (HA) formation on Ti-BGs surfaces was confirmed. Meanwhile, the presence of 5 mol.% compared to 3 mol.% increased the HA grain distribution and their size on the Ti-BGs surface. Additionally, MTT and ALP results confirmed that the optimal amount of titanium substitution in BG was 5 mol.%. Since 5 mol.% Ti incorporated BG (BG-5) had the highest biocompatibility level, antibacterial properties, maximum cell proliferation, and ALP activity among the synthesized Ti-BGs, it is presented as the best candidate for further in vivo investigations.  相似文献   
32.
In this study, we investigated surface and biological properties of Ag–Sr-doped mesoporous bioactive glass nanoparticle (Ag–Sr MBGN) loaded chitosan/gelatin coatings deposited by electrophoretic deposition (EPD) on 316L stainless steel. The EPD parameters, that is, deposition time, applied voltage, and distance between the electrodes was optimized by the Taguchi design of experiment (DoE) approach. Scanning electron microscopy (SEM) images illustrated the spherical morphology of the synthesized Ag–Sr MBGNs with the mean particle size of 160 ± 20 nm. Energy-dispersive X-ray (EDX) spectroscopy results confirmed the presence of Ag and Sr in the synthesized MBGNs. Optimum EPD parameters determined by DoE approach were 5 g/L of Ag–Sr MBGNs, deposition time of 5 min, and applied voltage of 30 V. SEM images confirmed that the coatings were fairly homogenous. Fourier-transform infrared spectroscopy and EDX results confirmed the presence of chitosan, gelatin, and Ag–Sr MBGNs in the coatings. Chitosan/gelatin/Ag–Sr MBGN composite coatings exhibited suitable wettability for the protein attachment and proliferation of osteoblast cells. The composite coatings exhibited suitable adhesion strength with the substrate. The coatings developed HA crystals upon immersion in simulated body fluid. The results of the turbidity test confirmed that the coatings are antibacterial to the Escherichia coli cells.  相似文献   
33.
In silico and in vitro methods were used to analyze ACE- and DPP-IV-inhibiting potential of Gouda cheese with a modified content of β-casein. Firstly, the BIOPEP-UWM database was used to predict the presence of ACE and DPP-IV inhibitors in casein sequences. Then, the following Gouda cheeses were produced: with decreased, increased, and normative content of β-casein after 1 and 60 days of ripening each (six variants in total). Finally, determination of the ACE/DPP-IV-inhibitory activity and the identification of peptides in respective Gouda-derived water-soluble extracts were carried out. The identification analyses were supported with in silico calculations, i.e., heatmaps and quantitative parameters. All Gouda variants exhibited comparable ACE inhibition, whereas DPP-IV inhibition was more diversified among the samples. The samples derived from Gouda with the increased content of β-casein (both stages of ripening) had the highest DPP-IV-inhibiting potency compared to the same samples measured for ACE inhibition. Regardless of the results concerning ACE and DPP-IV inhibition among the cheese samples, the heatmap showed that the latter bioactivity was predominant in all Gouda variants, presumably because it was based on the qualitative approach (i.e., peptide presence in the sample). Our heatmap did not include the bioactivity of a single peptide as well as its quantity in the sample. In turn, the quantitative parameters showed that the best sources of ACE/DPP-IV inhibitors were all Gouda-derived extracts obtained after 60 days of the ripening. Although our protocol was efficient in showing some regularities among Gouda cheese variants, in vivo studies are recommended for more extensive investigations of this subject.  相似文献   
34.
Polyunsaturated fatty acids (PUFAs) are essential FAs for human health. Cytochrome P450 oxygenates PUFAs to produce anti-inflammatory and pain-resolving epoxy fatty acids (EpFAs) and other oxylipins whose epoxide ring is opened by the soluble epoxide hydrolase (sEH/Ephx2), resulting in the formation of toxic and pro-inflammatory vicinal diols (dihydroxy-FAs). Pharmacological inhibition of sEH is a promising strategy for the treatment of pain, inflammation, cardiovascular diseases, and other conditions. We tested the efficacy of a potent, selective sEH inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), in an animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). Prophylactic TPPU treatment significantly ameliorated EAE without affecting circulating white blood cell counts. TPPU accumulated in the spinal cords (SCs), which was correlated with plasma TPPU concentration. Targeted lipidomics in EAE SCs and plasma identified that TPPU blocked production of dihydroxy-FAs efficiently and increased some EpFA species including 12(13)-epoxy-octadecenoic acid (12(13)-EpOME) and 17(18)-epoxy-eicosatrienoic acid (17(18)-EpETE). TPPU did not alter levels of cyclooxygenase (COX-1/2) metabolites, while it increased 12-hydroxyeicosatetraenoic acid (12-HETE) and other 12/15-lipoxygenase metabolites. These analytical results are consistent with sEH inhibitors that reduce neuroinflammation and accelerate anti-inflammatory responses, providing the possibility that sEH inhibitors could be used as a disease modifying therapy, as well as for MS-associated pain relief.  相似文献   
35.
Cheonggukjang (CGJ, fermented soybean paste), a traditional Korean fermented dish, has recently emerged as a functional food that improves blood circulation and intestinal regulation. Considering that excessive consumption of refined salt is associated with increased incidence of gastric cancer, high blood pressure, and stroke in Koreans, consuming CGJ may be desirable, as it can be made without salt, unlike other pastes. Soybeans in CGJ are fermented by Bacillus strains (B. subtilis or B. licheniformis), Lactobacillus spp., Leuconostoc spp., and Enterococcus faecium, which weaken the activity of putrefactive bacteria in the intestines, act as antibacterial agents against pathogens, and facilitate the excretion of harmful substances. Studies on CGJ have either focused on improving product quality or evaluating the bioactive substances contained in CGJ. The fermentation process of CGJ results in the production of enzymes and various physiologically active substances that are not found in raw soybeans, including dietary fiber, phospholipids, isoflavones (e.g., genistein and daidzein), phenolic acids, saponins, trypsin inhibitors, and phytic acids. These components prevent atherosclerosis, oxidative stress-mediated heart disease and inflammation, obesity, diabetes, senile dementia, cancer (e.g., breast and lung), and osteoporosis. They have also been shown to have thrombolytic, blood pressure-lowering, lipid-lowering, antimutagenic, immunostimulatory, anti-allergic, antibacterial, anti-atopic dermatitis, anti-androgenetic alopecia, and anti-asthmatic activities, as well as skin improvement properties. In this review, we examined the physiological activities of CGJ and confirmed its potential as a functional food.  相似文献   
36.
Studying the interactions between lipid membranes and various bioactive molecules (e.g., polyphenols) is important for determining the effects they can have on the functionality of lipid bilayers. This knowledge allows us to use the chosen compounds as potential inhibitors of bacterial and cancer cells, for elimination of viruses, or simply for keeping our healthy cells in good condition. As studying those effect can be exceedingly difficult on living cells, model lipid membranes, such as liposomes, can be used instead. Liposomal bilayer systems represent the most basic platform for studying those interactions, as they are simple, quite easy to prepare and relatively stable. They are especially useful for investigating the effects of bioactive compounds on the structure and kinetics of simple lipid membranes. In this review, we have described the most basic methods available for preparation of liposomes, as well as the essential techniques for studying the effects of bioactive compounds on those liposomes. Additionally, we have provided details for an easy laboratory implementation of some of the described methods, which should prove useful especially to those relatively new on this research field.  相似文献   
37.
微纳米生物材料目前已成为生物医用材料领域一个研究热点和难点。大量研究表明具有微纳米结构特征的生物材料表现出了积极的生物学响应。生物活性玻璃(BG)具有较高的生物活性、生物相容性,是一类重要的骨修复材料。而微纳米生物活性玻璃(MNBG)因其具有特殊的形态结构和理化性能,引起众多研究者的关注。但是目前对MNBG的研究还主要集中在制备、表征以及其表面类骨羟基磷灰石矿物在SBF溶液中的形成活性等方面,关于MNBG的细胞相容性以及基因激活性能方面的研究还鲜有报道。通过溶胶一凝胶法结合模板仿生技术合成了具有特殊微纳米结构和形态的MNBG,并将其浸提液与MG-63细胞共培养,研究生物玻璃溶出物对细胞增殖,成骨相关基因和蛋白表达的影响,结果证明相比于传统的熔融法制备的生物玻璃(45S5)浸提液,MNBG浸提液能够明显促进细胞增殖,激活细胞成骨相关基因,上调相关蛋白的表达,为设计和制备具有基因介导作用的新型生物活性玻璃骨修复材料提供了理论依据。  相似文献   
38.
《Ceramics International》2021,47(24):34836-34844
Bone defects accompanied by infection or inflammation can significantly delay the healing process. To simultaneously achieve controlled release of local antibiotics for infection control and bone healing, bone-implantable delivery systems have been considered as a promising strategy. This study aims to improve drug loading capacity of bone-implantable delivery systems by introducing hollow structure mesoporous bioactive glass nanospheres (HMBGs) through a sol–gel process. Particularly, such core–shell bimodal-porous structured nanoparticles were prepared through a sacrificing template using cetyltrimethylammonium bromide (CTAB) as surfactant. It was found that varying the amount of CTAB during the synthesis process is a simple and effective approach for tuning the particle size, morphology, and structure of HMBGs. For in vitro drug release, HMBGs could sustain storage and release of vancomycin hydrochloride (VAN) via diffusion-controlled mechanism, thereby inhibiting the bacteria growth in the subsequent bacterial study. Moreover, HMBGs incorporated with VAN provided a biomimetic microenvironment favored by cell adhesion and proliferation. These findings support the compatibility of HMBG nanoparticles with antibiotics and their potential application in the treatment of infectious bone defects.  相似文献   
39.
鸡蛋中的生物活性蛋白质和肽   总被引:1,自引:0,他引:1  
鸡蛋富含生物活性蛋白质,经酶解后也会产生多种生物活性肽,具有多种生理功能,如抑菌、抗高血压、抗氧化、促生长和增强免疫等作用。该文综述了鸡蛋中的生物活性蛋白和肽的研究进展。  相似文献   
40.
酶法水解苦荞麦蛋白制备生物活性肽的研究   总被引:2,自引:0,他引:2  
介绍了采用2709碱性蛋白酶水解苦荞麦蛋白粉制备生物活性肽,并对其纯化效果、抗氧化性、氨基酸组成进行了研究,结果表明:苦荞麦活性肽经Sep Hadex G-25层析后基本上得到了纯化;苦荞麦活性肽对超氧阴离子自由基有很强的清除作用,清除率达到28.67%;氨基酸组成分析表明,苦荞麦活性肽由17种氨基酸组成,含有7种人体必需的氨基酸(Val、Ile、Leu、Phe、Met、Thr、Lys),占苦荞麦活性肽氨基酸总含量的31.11%,具有较高的营养价值和较强的保健功能。  相似文献   
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