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821.
Accumulating evidence has indicated that intestinal microbiota is involved in the development of various human diseases, including cardiovascular diseases (CVDs). In the recent years, both human and animal experiments have revealed that alterations in the composition and function of intestinal flora, recognized as gut microflora dysbiosis, can accelerate the progression of CVDs. Moreover, intestinal flora metabolizes the diet ingested by the host into a series of metabolites, including trimethylamine N‐oxide, short chain fatty acids, secondary bile acid and indoxyl sulfate, which affects the host physiological processes by activation of numerous signalling pathways. The aim of this review was to summarize the role of gut microbiota in the pathogenesis of CVDs, including coronary artery disease, hypertension and heart failure, which may provide valuable insights into potential therapeutic strategies for CVD that involve interfering with the composition, function and metabolites of the intestinal flora.  相似文献   
822.
The triple‐negative breast cancer is the most malignant type of breast cancer. Its pathogenesis and prognosis remain poor despite the significant advances in breast cancer diagnosis and therapy. Meanwhile, long noncoding RNAs (LncRNAs) play a pivotal role in the progression of malignant tumors. In this study, we found that LncRNA‐ZEB2‐AS1 was dramatically up‐regulated in our breast cancer specimens and cells (MDA231), especially in metastatic tumor specimens and highly invasive cells, and high lncRNA‐ZEB2‐AS1 expression is associated with clinicopathologic features and short survival of breast cancer patients. LncRNA‐ZEB2‐AS1 promotes the proliferation and metastasis of MDA231 cells in SCID mice. Thus, it is regarded as an oncogene in triple‐negative breast cancer. It is mainly endo‐nuclear and situated near ZEB2, positively regulating ZEB2 expression and activating the epithelial mesenchymal transition via the PI3K/Akt/GSK3β/Zeb2 signaling pathway. Meanwhile, EGF‐induced F‐actin polymerization in MDA231 cells can be suppressed by reducing lncRNA‐ZEB2‐AS1 expression. The migration and invasion of triple‐negative breast cancer can be altered through cytoskeleton rearrangement. In summary, we demonstrated that lncRNA‐ZEB2‐AS1 is an important factor affecting the development of triple‐negative breast cancer and thus a potential oncogene target.  相似文献   
823.
International Journal of Peptide Research and Therapeutics - It is demonstrated that gonadotropin-releasing hormone (GnRH) analogs can directly inhibit the proliferation of reproductive tissue...  相似文献   
824.
Ni‐rich Li[NixCoyMn1?x?y]O2 (x ≥ 0.8) layered oxides are the most promising cathode materials for lithium‐ion batteries due to their high reversible capacity of over 200 mAh g?1. Unfortunately, the anisotropic properties associated with the α‐NaFeO2 structured crystal grains result in poor rate capability and insufficient cycle life. To address these issues, a micrometer‐sized Ni‐rich LiNi0.8Co0.1Mn0.1O2 secondary cathode material consisting of radially aligned single‐crystal primary particles is proposed and synthesized. Concomitant with this unique crystallographic texture, all the exposed surfaces are active {010} facets, and 3D Li+ ion diffusion channels penetrate straightforwardly from surface to center, remarkably improving the Li+ diffusion coefficient. Moreover, coordinated charge–discharge volume change upon cycling is achieved by the consistent crystal orientation, significantly alleviating the volume‐change‐induced intergrain stress. Accordingly, this material delivers superior reversible capacity (203.4 mAh g?1 at 3.0–4.3 V) and rate capability (152.7 mAh g?1 at a current density of 1000 mA g?1). Further, this structure demonstrates excellent cycling stability without any degradation after 300 cycles. The anisotropic morphology modulation provides a simple, efficient, and scalable way to boost the performance and applicability of Ni‐rich layered oxide cathode materials.  相似文献   
825.
Microglia, as the resident brain immune cells, can exhibit a broad range of activation phenotypes, which have been implicated in a multitude of central nervous system disorders. Current widely studied microglial cell lines are mainly derived from neonatal rodent brain that can limit their relevance to homeostatic function and disease‐related neuroimmune responses in the adult brain. Recently, an adult mouse brain‐derived microglial cell line has been established; however, a comprehensive proteome dataset remains lacking. Here, an optimization method for sensitive and rapid quantitative proteomic analysis of microglia is described that involves suspension trapping (S‐Trap) for efficient and reproducible protein extraction from a limited number of microglial cells expected from an adult mouse brain (≈300 000). Using a 2‐h gradient on a 75‐cm UPLC column with a modified data dependent acquisition method on a hybrid quadrupole‐Orbitrap mass spectrometer, 4855 total proteins have been identified where 4698 of which are quantifiable by label‐free quantitation with a median and average coefficient of variation (CV) of 6.7% and 10.6%, respectively. This dataset highlights the high depth of proteome coverage and related quantitation precision of the adult‐derived microglial proteome including proteins associated with several key pathways related to immune response. Data are available via ProteomeXchange with identifier PXD012006.  相似文献   
826.
Protein posttranslational modifications critically regulate a range of physiological and disease processes. In addition to tyrosine, serine, and threonine phosphorylation, reversible N‐ε acylation and alkylation of protein lysine residues also modulate diverse aspects of cellular function. Studies of lysine acyl and alkyl modifications have focused on nuclear proteins in epigenetic regulation; however, lysine modifications are also prevalent on cytosolic proteins to serve increasingly apparent, although less understood roles in cell regulation. Here, the methyl‐lysine (meK) proteome of anucleate blood platelets is characterized. With high‐resolution, multiplex MS methods, 190 mono‐, di‐, and tri‐meK modifications are identified on 150 different platelet proteins—including 28 meK modifications quantified by tandem mass tag (TMT) labeling. In addition to identifying meK modifications on calmodulin (CaM), GRP78 (HSPA5, BiP), and EF1A1 that have been previously characterized in other cell types, more novel modifications are also uncovered on cofilin, drebin‐like protein (DBNL, Hip‐55), DOCK8, TRIM25, and numerous other cytoplasmic proteins. Together, the results and analyses support roles for lysine methylation in mediating cytoskeletal, translational, secretory, and other cellular processes. MS data for this study have been deposited into the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD012217.  相似文献   
827.
828.
Reduced quantity and quality of stem cells in aged individuals hinders cardiac repair and regeneration after injury. We used young bone marrow (BM) stem cell antigen 1 (Sca‐1) cells to reconstitute aged BM and rejuvenate the aged heart, and examined the underlying molecular mechanisms. BM Sca‐1+ or Sca‐1? cells from young (2–3 months) or aged (18–19 months) GFP transgenic mice were transplanted into lethally irradiated aged mice to generate 4 groups of chimeras: young Sca‐1+, young Sca‐1?, old Sca‐1+, and old Sca‐1?. Four months later, expression of rejuvenation‐related genes (Bmi1, Cbx8, PNUTS, Sirt1, Sirt2, Sirt6) and proteins (CDK2, CDK4) was increased along with telomerase activity and telomerase‐related protein (DNA‐PKcs, TRF‐2) expression, whereas expression of senescence‐related genes (p16INK4a, P19ARF, p27Kip1) and proteins (p16INK4a, p27Kip1) was decreased in Sca‐1+ chimeric hearts, especially in the young group. Host cardiac endothelial cells (GFP?CD31+) but not cardiomyocytes were the primary cell type rejuvenated by young Sca‐1+ cells as shown by improved proliferation, migration, and tubular formation abilities. C‐X‐C chemokine CXCL12 was the factor most highly expressed in homed donor BM (GFP+) cells isolated from young Sca‐1+ chimeric hearts. Protein expression of Cxcr4, phospho‐Akt, and phospho‐FoxO3a in endothelial cells derived from the aged chimeric heart was increased, especially in the young Sca‐1+ group. Reconstitution of aged BM with young Sca‐1+ cells resulted in effective homing of functional stem cells in the aged heart. These young, regenerative stem cells promoted aged heart rejuvenation through activation of the Cxcl12/Cxcr4 pathway of cardiac endothelial cells.  相似文献   
829.
830.

This study analyzes the influence of different types of molecules (tween, lecithin, xanthan gum, and methylcellulose) on the physical properties (flow behavior and particle size) and microstructure of oil-in-water (o/w) emulsions before and during in vitro intestinal digestion. The release of free fatty acids during a simulated intestinal stage has also been examined. The results show that various o/w emulsions present different rates and extents of lipolysis and that these differences are not primarily due to their rheological properties nor to the droplet size/surface area available for the action of lipase. Rather, the observed differences in the kinetics of lipolysis are most likely attributable to the nature and location of each type of molecule in their respective o/w emulsions as well as to their interactions with intestinal components. These results shed light on the mechanisms by which the interfacial layer controls lipid digestion, paving the way for a practical application of some of these emulsions in the production of foods used for regulating dietary lipid digestion in order to prevent and treat obesity and related disorders.

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