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931.
Esther Larrea Celia Fernndez-Rubio Jos Pea-Guerrero Elizabeth Guruceaga Paul A. Nguewa 《International journal of molecular sciences》2022,23(21)
Around 15% of cancer cases are attributable to infectious agents. Epidemiological studies suggest that an association between leishmaniasis and cancer does exist. Recently, the homologue of PES1 in Leishmania major (LmjPES) was described to be involved in parasite infectivity. Mammalian PES1 protein has been implicated in cellular processes like cell cycle regulation. Its BRCT domain has been identified as a key factor in DNA damage-responsive checkpoints. This work aimed to elucidate the hypothetical oncogenic implication of BRCT domain from LmjPES in host cells. We generated a lentivirus carrying this BRCT domain sequence (lentiBRCT) and a lentivirus expressing the luciferase protein (lentiLuc), as control. Then, HEK293T and NIH/3T3 mammalian cells were infected with these lentiviruses. We observed that the expression of BRCT domain from LmjPES conferred to mammal cells in vitro a greater replication rate and higher survival. In in vivo experiments, we observed faster tumor growth in mice inoculated with lentiBRCT respect to lentiLuc HEK293T infected cells. Moreover, the lentiBRCT infected cells were less sensitive to the genotoxic drugs. Accordingly, gene expression profiling analysis revealed that BRCT domain from LmjPES protein altered the expression of proliferation- (DTX3L, CPA4, BHLHE41, BMP2, DHRS2, S100A1 and PARP9), survival- (BMP2 and CARD9) and chemoresistance-related genes (DPYD, Dok3, DTX3L, PARP9 and DHRS2). Altogether, our results reinforced the idea that in eukaryotes, horizontal gene transfer might be also achieved by parasitism like Leishmania infection driving therefore to some crucial biological changes such as proliferation and drug resistance. 相似文献
932.
Doaa M. AlEraky Hatem M. Abuohashish Amr S. Bugshan Maha M. Abdelsalam Hussain A. AlHawaj Taleb T. AlKhamis Fatimah A. AlDossary Nabras M. Alrayes Yasser M. Ragab Zeinab AbdelKhalek Omneya M. Helmy Mohammed A. Ramadan 《International journal of molecular sciences》2022,23(21)
Helicobacter pylori (H. pylori) has been identified as a group-1 definite carcinogen. As of yet, there is no available vaccine for this microorganism. Our study aimed to identify antigenic peptides in H. pylori using an in silico proteomic approach, and to evaluate their effectiveness as potential vaccine candidates. Four different peptide sequences were prioritized using the reverse vaccinology, namely, CagA1, CagA2, VacA, and SabA. Peptides emulsified with Freunde’s adjuvant were used to immunize BALB/C mice. Subcutaneously immunized mice were challenged by oral administration of H. pylori. IgG, IgA, IL4, and IL17 were detected in mice sera. Histopathology of the dissected stomach of vaccinated and control mice were assessed using H&E stain. IgG was significantly higher in mice vaccinated with SabA. IL-4 was significantly increased in CagA1, CagA2, VacA, and SabA vaccinated mice compared to the adjuvant group. Additionally, histopathological examination of gastric tissue showed a protective effect in the vaccinated groups compared to adjuvant and PBS groups. Our findings indicate a promising effect of the tested epitopes, particularly the SabA antigen, to induce an immune response against H. pylori. 相似文献
933.
提出一种基于元胞蚂蚁算法的故障诊断方式。该方法利用模式识别中的近邻准则,使用元胞蚂蚁算法实现故障的分类,达到故障诊断的目的。最后用一实例进行仿真,结果表明该方法拥有较强的可行性和实用性。 相似文献
934.
针对传统数字滤波在红外光谱细胞水分检测中采样点平均后各峰值削减的严重问题,提出了一种基于LabVIEW的滤波方案,设计了相应的相关算法,并对滤波信号进行时域和频域分析;在此基础上,构建并开发了基于LabVIEW的数据分析处理系统;实验结果表明,该数据分析处理系统测量精度高,数据实时处理能力强,具有良好的推广和应用前景。 相似文献
935.
镇沅金矿斑毛沟尾矿库投入使用后,存在排洪设施损坏、子坝上升速率快、微细粒尾矿沉积慢、滩长短、泥面缓、尾矿堆筑子坝困难等问题.通过采取排洪设施加固和岸坡防护、土石料筑子坝、槽孔管排渗、旋流器分级沉砂筑坝等多种有效措施,确保了尾矿库的安全运行.该研究对微细粒尾矿排放具有示范作用,是一种可借鉴推广的尾矿库安全运行模式. 相似文献
936.
937.
Pei-Wei Weng Narpati Wesa Pikatan Syahru Agung Setiawan Vijesh Kumar Yadav Iat-Hang Fong Chia-Hung Hsu Chi-Tai Yeh Wei-Hwa Lee 《International journal of molecular sciences》2022,23(13)
Osteoarthritis (OA) is most prevalent in older individuals and exerts a heavy social and economic burden. However, an effective and noninvasive approach to OA treatment is currently not available. Chondrocyte senescence has recently been proposed as a key pathogenic mechanism in the etiology of OA. Furthermore, senescent chondrocytes (SnCCs) can release various proinflammatory cytokines, proteolytic enzymes, and other substances known as the senescence-associated secretory phenotype (SASP), allowing them to connect with surrounding cells and induce senesce. Studies have shown that the pharmacological elimination of SnCCs slows the progression of OA and promotes regeneration. Growth differentiation factor 15 (GDF15), a member of the tumor growth factor (TGF) superfamily, has recently been identified as a possible aging biomarker and has been linked to a variety of clinical conditions, including coronary artery disease, diabetes, and multiple cancer types. Thus, we obtained data from a publicly available single-cell sequencing RNA database and observed that GDF15, a critical protein in cellular senescence, is highly expressed in early OA. In addition, GDF15 is implicated in the senescence and modulation of MAPK14 in OA. Tissue and synovial fluid samples obtained from OA patients showed overexpression of GDF15. Next, we treated C20A4 cell lines with interleukin (IL)-1β with or without shGDF15 then removed the conditioned medium, and cultured C20A4 and HUVEC cell lines with the aforementioned media. We observed that C20A4 cells treated with IL-1β exhibited increased GDF15 secretion and that chondrocytes cultured with media derived from IL-1β–treated C20A4 exhibited senescence. HUVEC cell migration and tube formation were enhanced after culturing with IL-1β-treated chondrocyte media; however, decreased HUVEC cell migration and tube formation were noted in HUVEC cells cultured with GDF15-loss media. We tested the potential of inhibiting GDF15 by using a GDF15 neutralizing antibody, GDF15-nAb. GDF15-nAb exerted a similar effect, resulting in the molecular silencing of GDF15 in vivo and in vitro. Our results reveal that GDF15 is a driver of SnCCs and can contribute to OA progression by inducing angiogenesis. 相似文献
938.
本文旨在比较两种养殖模式下大口黑鲈肌肉的品质差异,以期为池塘工业化养殖模式的改进与推广提供有价值的理论指导。选取2月龄幼鱼(体长约5 cm)随机分为静水养殖组和流水养殖组,分别采用传统池塘养殖和流水槽养殖(流速为3 cm/s)。培养12个月后,采集各组鱼体背部轴上肌,采用常规方法对鱼肉营养成分组成及质构特性进行测定,利用气相色谱-质谱联用仪(GC-MS)和高效液相色谱(HPLC)对肌肉脂肪酸、氨基酸进行测定。结果显示,与静水养殖组比较,流水养殖的鲈鱼肌肉蛋白质含量显著提高(p<0.05),羟脯氨酸、胶原和胶原蛋白含量极显著提高(p<0.01),脂肪含量显著降低(p<0.05),流水养殖组肌肉的质构分析显示硬度、弹性、胶黏性和咀嚼性均显著提高(p<0.05)。此外,流水养殖显著提高了鱼肉多不饱和脂肪酸(PUFA)、ω-6脂肪酸以及油酸、亚油酸、二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)含量。同时,必需氨基酸含量,尤其是谷氨酸(Glu)、缬氨酸(Val)、亮氨酸(Leu)、异亮氨酸(Ile)含量均有显著性提高(p<0.05)。结果表明,相较于传统池塘养殖,池塘工业化养殖模式可提升鲈鱼营养价值,使肉质更加紧实富有嚼劲。 相似文献
939.
边缘划分问题是数据分析的核心问题之一.针对晶体数据的边缘分类问题,引入同调论的思想,提出了胞腔同调边缘算法和正则胞腔同调边缘学习算法及上同调边缘学习算法,并将其应用于晶体结构预测和分类.鉴于晶体数据满足对称群的基本性质,引用同调代数的方法从机器学习的角度来研究数据的边缘分类问题.为了从不同角度构造分类模型,先从相对同调边缘展开为局部同调和定向同调,再深入到上同调边缘算法和腔胞同调边缘算法,由着重系数定理扩展到正则胞腔同调,进而延伸至相对流形.仿真结果表明了算法的有效性. 相似文献
940.
This paper points out an idealization of considerable significance in a recent numerical model of a solar pond due to Wang and Akbarzadeh [3] and outlines the refinements required in the formulation of the above model. Typical temperature calculations from teh resultant model are also presented. of the above model. Typical temperature calculations from the resultant model are also presented. 相似文献