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71.
Aging is one of the most intriguing processes of human ontogenesis. It is associated with the development of a wide variety of diseases affecting all organs and their systems. The victory over aging is the most desired goal of scientists; however, it is hardly achievable in the foreseeable future due to the complexity and ambiguity of the process itself. All body systems age, lose their performance, and structural disorders accumulate. The cardiovascular system is no exception. And it is cardiovascular diseases that occupy a leading position as a cause of death, especially among the elderly. The aging of the cardiovascular system is well described from a mechanical point of view. Moreover, it is known that at the cellular level, a huge number of mechanisms are involved in this process, from mitochondrial dysfunction to inflammation. It is on these mechanisms, as well as the potential for taking control of the aging of the cardiovascular system, that we focused on in this review.  相似文献   
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A 72-year-old female patient with mixed rheumatic mitral valve disease and persistent atrial fibrillation underwent mitral valve replacement and suffered from a combined thrombosis of the bioprosthetic valve and the left atrium as soon as 2 days post operation. The patient immediately underwent repeated valve replacement and left atrial thrombectomy. Yet, four days later the patient died due to the recurrent prosthetic valve and left atrial thrombosis which both resulted in an extremely low cardiac output. In this patient’s case, the thrombosis was notable for the resistance to anticoagulant therapy as well as for aggressive neutrophil infiltration and release of neutrophil extracellular traps (NETs) within the clot, as demonstrated by immunostaining. The reasons behind these phenomena remained unclear, as no signs of sepsis or contamination of the BHV were documented, although the patient was diagnosed with inherited thrombophilia that could impede the fibrinolysis. The described case highlights the hazard of immunothrombosis upon valve replacement and elucidates its mechanisms in this surgical setting.  相似文献   
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Assess the level of mitochondrial DNA depending on the presence of multiple organ failure in patients after heart surgery. The study included 60 patients who underwent surgical treatment of valvular heart disease using cardiopulmonary bypass. Uncomplicated patients were included in the 1st group (n = 30), patients with complications and multiple organ failure (MOF) were included in the 2nd group (n = 30). Serum mtDNA levels were determined by quantitative real-time polymerase chain reaction with fluorescent dyes. Mitochondrial DNA gene expression did not differ between group before surgery. Immediately after the intervention, cytochrome B gene expression was higher in the group with MOF, and it remained high during entire follow-up period. A similar trend was observed in cytochrome oxidase gene expression. Increased NADH levels of gene expressions during the first postoperative day were noted in both groups, the expression showed tendency to increase on the third postoperative day. mtDNA gene expression in the “MOF present” group remained at a higher level compared with the group without complications. A positive correlation was reveled between the severity of MOF according to SOFA score and the level of mtDNA (r = 0.45; p = 0.028) for the end-point “First day”. The ROC analysis showed that mtDNA circulating in plasma (AUC = 0.605) can be a predictor of MOF development. The level of mtDNA significantly increases in case of MOF, irrespective of its cause. (2) The expression of mtDNA genes correlates with the level of MOF severity on the SOFA score.  相似文献   
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A novel multi-camera active-vision reconfiguration method is proposed for the markerless shape recovery of unknown deforming objects. The proposed method implements a model fusion technique to obtain a complete 3D mesh-model via triangulation and a visual hull. The model is tracked using an adaptive particle filtering algorithm, yielding a deformation estimate that can, then, be used to reconfigure the cameras for improved surface visibility. The objective of reconfiguration is maximization of the total surface area visible through stereo triangulation. The surface area based objective function directly relates to maximizing the accuracy of the shape recovered, as stereo triangulation is more accurate than visual hull building when the number of viewpoints is limited. The reconfiguration process comprises workspace discretization, visibility estimation, optimal stereo-pose selection, and path planning to ensure 2D tracked feature consistency. In contrast to other reconfiguration techniques that rely on a priori known, and at times static, object models, our method focuses on a priori unknown deforming objects. The proposed method operates on-line and has been shown to outperform static-camera based systems through extensive simulations and experiments with an increased surface visibility in the presence of occluding obstacles.  相似文献   
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Whole exome sequencing of invasive mammary carcinomas revealed the association of mutations in PTEN and ZFHX3 tumor suppressor genes (TSGs). We generated single and combined PTEN and ZFHX3 knock-outs (KOs) in the immortalized mammary epithelial cell line MCF10A to study the role of these genes and their potential synergy in migration regulation. Inactivation of PTEN, but not ZFHX3, induced the formation of large colonies in soft agar. ZFHX3 inactivation in PTEN KO, however, increased colony numbers and normalized their size. Cell migration was affected in different ways upon PTEN and ZFHX3 KO. Inactivation of PTEN enhanced coordinated cell motility and thus, the collective migration of epithelial islets and wound healing. In contrast, ZFHX3 knockout resulted in the acquisition of uncoordinated cell movement associated with the appearance of immature adhesive junctions (AJs) and the increased expression of the mesenchymal marker vimentin. Inactivation of the two TSGs thus induces different stages of partial epithelial-to-mesenchymal transitions (EMT). Upon double KO (DKO), cells displayed still another motile state, characterized by a decreased coordination in collective migration and high levels of vimentin but a restoration of mature linear AJs. This study illustrates the plasticity of migration modes of mammary cells transformed by a combination of cancer-associated genes.  相似文献   
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