正Dear Editor,NCC(Na-Cl cotransporter)is a cotransporter mainly distributed in the distal tubule of the kidney,functioning to reabsorb sodium and chloride ions from the tubular fluid into the cells of the renal distal convoluted tubule.It is a 相似文献
Percutaneous coronary intervention (PCI) has become the primary treatment for patients with coronary heart disease because of its minimally invasive nature and high efficiency. Anatomical studies have shown that most coronary vessels gradually shrink, and the vessels gradually become thinner from the proximal to the distal end. In this paper, the effects of different stent expansion methods on the mechanical and hemodynamic behaviors of coronary vessels and stents were studied. To perform a structural-mechanical analysis of stent implantation, the coronary vessels with branching vessels and the coronary vessels with large bending curvature are selected. The two characteristic structures are implanted in equal diameter expansion mode and conical expansion mode, and the stress and mechanical behaviors of the coronary vessels and stents are analyzed. The results of the structural-mechanical analysis showed that the mechanical behaviors and fatigue performance of the cobalt-chromium alloy stent were good, and the different expansion modes of the stent had little effect on the fatigue performance of the stent. However, the equal diameter expansion mode increased distal coronary artery stress and the risk of vascular injury. The computational fluid dynamics analysis results showed that different stent expansion methods had varied effects on coronary vessel hemodynamics and that the wall shear stress distribution of conical stent expansion is more uniform compared with equal diameter expansion. Additionally, the vortex phenomenon is not apparent, the blood flow velocity is slightly increased, the hydrodynamic environment is more reasonable, and the risk of coronary artery injury is reduced.
There is a growing need for successful bone tissue engineering strategies and advanced biomaterials that mimic the structure and function of native tissues carry great promise. Successful bone repair approaches may include an osteoconductive scaffold, osteoinductive growth factors, cells with an osteogenic potential and capacity for graft vascularisation. To increase osteoinductivity of biomaterials, the local combination and delivery of growth factors has been developed. In the present study we investigated the osteogenic effects of calcium phosphate (CaP)-coated nanofiber mesh tube-mediated delivery of BMP-7 from a PRP matrix for the regeneration of critical sized segmental bone defects in a small animal model. Bilateral full-thickness diaphyseal segmental defects were created in twelve male Lewis rats and nanofiber mesh tubes were placed around the defect. Defects received either treatment with a CaP-coated nanofiber mesh tube (n?=?6), an un-coated nanofiber mesh tube (n=6) a CaP-coated nanofiber mesh tube with PRP (n=6) or a CaP-coated nanofiber mesh tube in combination with 5?μg?BMP-7 and PRP (n?=?6). After 12?weeks, bone volume and biomechanical properties were evaluated using radiography, microCT, biomechanical testing and histology. The results demonstrated significantly higher biomechanical properties and bone volume for the BMP group compared to the control groups. These results were supported by the histological evaluations, where BMP group showed the highest rate of bone regeneration within the defect. In conclusion, BMP-7 delivery via PRP enhanced functional bone defect regeneration, and together these data support the use of BMP-7 in the treatment of critical sized defects. 相似文献
Substantial evidence indicates that immune activation at stroma can be rerouted in a tumor-promoting direction. CD69 is an immunoregulatory molecule expressed by early-activated leukocytes at sites of chronic inflammation, and CD69(+) T cells have been found to promote human tumor progression. In this study, we showed that, upon encountering autologous CD69(+) T cells, tumor macrophages (MΦs) acquired the ability to produce much greater amounts of IDO protein in cancer nests. The T cells isolated from the hepatocellular carcinoma tissues expressed significantly more CD69 molecules than did those on paired circulating and nontumor-infiltrating T cells; these tumor-derived CD69(+) T cells could induce considerable IDO in monocytes. Interestingly, the tumor-associated monocytes/MΦs isolated from hepatocellular carcinoma tissues or generated by in vitro culture effectively activated circulating T cells to express CD69. IL-12 derived from tumor MΦs was required for early T cell activation and subsequent IDO expression. Moreover, we found that conditioned medium from IDO(+) MΦs effectively suppressed T cell responses in vitro, an effect that could be reversed by adding extrinsic IDO substrate tryptophan or by pretreating MΦs with an IDO inhibitor 1-methyl-DL-tryptophan. These data revealed a fine-tuned collaborative action between different types of immune cells to counteract T cell responses in tumor microenvironment. Such an active induction of immune tolerance should be considered for the rational design of effective immune-based anticancer therapies. 相似文献
Most ovarian cancers originate from the ovarian surface epithelium and are characterized by aneuploid karyotypes. Aneuploidy, a consequence of chromosome instability, is an early event during the development of ovarian cancers. However, how aneuploid cells are evolved from normal diploid cells in ovarian cancers remains unknown. In the present study, cytogenetic analyses of a mouse syngeneic ovarian cancer model revealed that diploid mouse ovarian surface epithelial cells (MOSECs) experienced an intermediate tetraploid cell stage, before evolving to aneuploid (mainly near-tetraploid) cells. Using long-term live-cell imaging followed by fluorescence in situ hybridization (FISH), we demonstrated that tetraploid cells originally arose from cytokinesis failure of bipolar mitosis in diploid cells, and gave rise to aneuploid cells through chromosome mis-segregation during both bipolar and multipolar mitoses. Injection of the late passage aneuploid MOSECs resulted in tumor formation in C57BL/6 mice. Therefore, we reveal a pathway for the evolution of diploid to aneuploid MOSECs and elucidate a mechanism for the development of near-tetraploid ovarian cancer cells. 相似文献