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1.
Deposition of amyloid β (Aβ) fibrils in the brain is a key pathologic hallmark of Alzheimer’s disease. A class of polyphenolic biflavonoids is known to have anti-amyloidogenic effects by inhibiting aggregation of Aβ and promoting disaggregation of Aβ fibrils. In the present study, we further sought to investigate the structural basis of the Aβ disaggregating activity of biflavonoids and their interactions at the atomic level. A thioflavin T (ThT) fluorescence assay revealed that amentoflavone-type biflavonoids promote disaggregation of Aβ fibrils with varying potency due to specific structural differences. The computational analysis herein provides the first atomistic details for the mechanism of Aβ disaggregation by biflavonoids. Molecular docking analysis showed that biflavonoids preferentially bind to the aromatic-rich, partially ordered N-termini of Aβ fibril via the π–π interactions. Moreover, docking scores correlate well with the ThT EC50 values. Molecular dynamic simulations revealed that biflavonoids decrease the content of β-sheet in Aβ fibril in a structure-dependent manner. Hydrogen bond analysis further supported that the substitution of hydroxyl groups capable of hydrogen bond formation at two positions on the biflavonoid scaffold leads to significantly disaggregation of Aβ fibrils. Taken together, our data indicate that biflavonoids promote disaggregation of Aβ fibrils due to their ability to disrupt the fibril structure, suggesting biflavonoids as a lead class of compounds to develop a therapeutic agent for Alzheimer’s disease.  相似文献   
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The Gli-B1-encoded γ-gliadins and non-coding γ-gliadin DNA sequences for 15 different alleles of common wheat have been compared using seven tests: electrophoretic mobility (EM) and molecular weight (MW) of the encoded major γ-gliadin, restriction fragment length polymorphism patterns (RFLPs) (three different markers), Gli-B1-γ-gliadin-pseudogene known SNP markers (Single nucleotide polymorphisms) and sequencing the pseudogene GAG56B. It was discovered that encoded γ-gliadins, with contrasting EM, had similar MWs. However, seven allelic variants (designated from I to VII) differed among them in the other six tests: I (alleles Gli-B1i, k, m, o), II (Gli-B1n, q, s), III (Gli-B1b), IV (Gli-B1e, f, g), V (Gli-B1h), VI (Gli-B1d) and VII (Gli-B1a). Allele Gli-B1c (variant VIII) was identical to the alleles from group IV in four of the tests. Some tests might show a fine difference between alleles belonging to the same variant. Our results attest in favor of the independent origin of at least seven variants at the Gli-B1 locus that might originate from deeply diverged genotypes of the donor(s) of the B genome in hexaploid wheat and therefore might be called “heteroallelic”. The donor’s particularities at the Gli-B1 locus might be conserved since that time and decisively contribute to the current high genetic diversity of common wheat.  相似文献   
4.
In this study, we investigate the immunomodulatory effects of a novel antimicrobial peptide, YD1, isolated from Kimchi, in both in vitro and in vivo models. We establish that YD1 exerts its anti-inflammatory effects via up-regulation of the Nrf2 pathway, resulting in the production of HO-1, which suppresses activation of the NF-κB pathway, including the subsequent proinflammatory cytokines IL-1β, IL-6, and TNF-α. We also found that YD1 robustly suppresses nitric oxide (NO) and prostaglandin E2 (PGE2) production by down-regulating the expression of the upstream genes, iNOS and COX-2, acting as a strong antioxidant. Collectively, YD1 exhibits vigorous anti-inflammatory and antioxidant activity, presenting it as an interesting potential therapeutic agent.  相似文献   
5.
Owing to the prohibition of cosmetic animal testing, various attempts have recently been made using skin-on-a-chip (SOC) technology as a replacement for animal testing. Previously, we reported the development of a pumpless SOC capable of drug testing with a simple drive using the principle that the medium flows along the channel by gravity when the chip is tilted using a microfluidic channel. In this study, using pumpless SOC, instead of drug testing at the single-cell level, we evaluated the efficacy of α-lipoic acid (ALA), which is known as an anti-aging substance in skin equivalents, for skin tissue and epidermal structure formation. The expression of proteins and changes in genotyping were compared and evaluated. Hematoxylin and eosin staining for histological analysis showed a difference in the activity of fibroblasts in the dermis layer with respect to the presence or absence of ALA. We observed that the epidermis layer became increasingly prominent as the culture period was extended by treatment with 10 μM ALA. The expression of epidermal structural proteins of filaggrin, involucrin, keratin 10, and collagen IV increased because of the effect of ALA. Changes in the epidermis layer were noticeable after the ALA treatment. As a result of aging, damage to the skin-barrier function and structural integrity is reduced, indicating that ALA has an anti-aging effect. We performed a gene analysis of filaggrin, involucrin, keratin 10, integrin, and collagen I genes in ALA-treated human skin equivalents, which indicated an increase in filaggrin gene expression after ALA treatment. These results indicate that pumpless SOC can be used as an in vitro skin model similar to human skin, protein and gene expression can be analyzed, and it can be used for functional drug tests of cosmetic materials in the future. This technology is expected to contribute to the development of skin disease models.  相似文献   
6.
随着原油品质的下降,在炼油过程中造成的腐蚀问题,受到广泛重视,腐蚀监控技术得到快速发展。炼油装置中的均匀腐蚀情况可以通过电阻探针监控法和电感探针监控法来进行监控,点腐蚀情况可以通过线性极化探针监测法和电化学噪声监控技术来进行监控,应力腐蚀情况可以通过氢通量测量技术和线性极化探针监控法来进行监控。基于这些腐蚀监控技术,建立腐蚀监控系统,用于全面监控炼油装置的腐蚀情况,基本实现了对炼油装置腐蚀情况的连续监测,以便及时给出应对措施,可有效预防腐蚀的发生,减少安全事故。  相似文献   
7.
油气处理站库集散式控制系统(DCS)是对油、气、水处理全过程、多环节、多领域,以生产过程数据实时采集及处理、智能分析、控制的工业控制系统。集散式控制系统实现智能化和管控一体化,仅依靠传统防火墙和IT信息安全技术体系已无法有效应对,亟需在攻防地位严重不对称、存在大量被漏洞被后门的现实环境中,建立全生命周期管控的深度防护整体解决方案。  相似文献   
8.
张凯悦  张鸿 《计算机应用》2021,41(10):3010-3016
针对已有的航运监控图像识别模型C3D里中级表征学习能力有限,有效特征的提取容易受到噪声的干扰,且特征的提取忽视了整体特征与局部特征之间关系的问题,提出了一种新的基于注意力机制网络的航运监控图像识别模型。该模型基于卷积神经网络(CNN)框架,首先,通过特征提取器提取图像的浅层次特征;然后,基于CNN对不同区域激活特征的不同响应强度,生成注意力信息并实现对局部判别性特征的提取;最后,使用多分支的CNN结构融合局部判别性特征和图像全局纹理特征,从而利用局部判别性特征和图像全局纹理特征的交互关系提升CNN学习中级表征的能力。实验结果表明,所提出的模型在航运图像数据集上的识别准确率达到91.8%,相较于目前的C3D模型提高了7.2个百分点,相较于判别滤波器组卷积神经网络(DFL-CNN)模型提高了0.6个百分点。可见所提模型能够准确判断船舶的状态,可以有效应用于航运监控项目。  相似文献   
9.
通过系统梳理、比较大量古籍文献来探究“玫瑰” 词源,结论归结如下:1)“玫瑰”较早在汉代为“火齐(音 霁)珠”的宝珠,后晋代《西京杂记》中首次出现了作植物义 的西汉“玫瑰”,但其与现代植物学中玫瑰(Rosa rugosa) 的关联性尚缺乏直接证据;2)“玫瑰”含义的转变体现了珠 宝与同名植物在形、色、香上的关联;3)古代“玫瑰”二字 音形多重,早在汉代就记有与现代相同的读法,早期“玫” 又作“玟”,“瑰”还可音“回”;4)玫瑰作为植物别名众 多,如徘徊花、离娘草、玉蕊等,其中一些还与蔷薇属其他植 物有关联,且寓意多元。对古代“玫瑰”含义的考证研究,有 利于中国传统植物资源和文化的保护和传承,也为我国花文化 的创新与发展提供重要参考。  相似文献   
10.
为了提升煤矿车辆异常行为检测水平,设计了基于红外遥感信息的煤矿车辆异常行为检测方法。该方法引入清晰度权重以及拉伸系数实现红外遥感图像中目标煤矿车辆部位的局部增强,利用均值漂移算法跟踪增强后的红外遥感图像中目标煤矿车辆,依据煤矿车辆跟踪结果提取煤矿车辆运动方向、运动速度以及运动方向3项异常行为检测参数,采用加权融合方法处理煤矿车辆异常行为检测参数的状态函数,融合结果高于所设定阈值时,煤矿车辆存在异常行为,否则煤矿车辆为正常行驶状态。实验结果表明,该方法可利用煤矿车辆位置、车辆行驶速度以及车辆方向变化检测煤矿车辆异常行为,具有较高的应用性。  相似文献   
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