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排序方式: 共有550条查询结果,搜索用时 46 毫秒
81.
Gloria Invernici Paolo Madeddu Costanza Emanueli Eugenio A. Parati Giulio Alessandri 《Cytotechnology》2008,58(1):43-47
Vasculogenesis, the formation of blood vessels in embryonic or fetal tissue mediated by immature vascular cells (i.e., angioblasts),
is poorly understood. Here we report a summary of our recent studies on the identification of a population of vascular progenitor
cells (VPCs) in human fetal aorta. These undifferentiated mesenchymal cells co-express endothelial and myogenic markers (CD133+,
CD34+, KDR+, desmin+) and are localized in outer layer of the aortic stroma of 11–12 weeks old human fetuses. Under stimulation
with VEGF-A or PDGF-BB, VPCs give origin to a mixed population of mature endothelial and mural cells, respectively. When embedded
in a three-dimensional collagen gel, VPCs organize into cohesive cellular cords that resembled mature vascular structures.
The therapeutic efficacy of a small number of VPCs transplanted into ischemic limb muscle was demonstrated in immunodeficient
mice. Investigation of the effect of VPCs on experimental heart ischemia and on diabetic ischemic ulcers in mice is in progress
and seems to confirm their efficacy. On the whole, fetal aorta represents an important source for the investigation of phenotypic
and functional features of human vascular progenitor cells. 相似文献
82.
A method has been developed to allow the level of F0F1ATP synthase capacity and the quantity of IF1 bound to this enzyme be measured in single biopsy samples of goat heart. ATP synthase capacity was determined from the maximal mitochondrial ATP hydrolysis rate and IF1 content was determined by detergent extraction followed by blue native gel electrophoresis, two-dimensional SDS-PAGE and immunoblotting with anti-IF1 antibodies.Anaesthetized open-chest goats were subjected to ischemic preconditioning and/or sudden increases of coronary blood flow (CBF) (reactive hyperemia). When hyperemia was induced before ischemic preconditioning, a steep increase in synthase capacity, followed by a deep decrease, was observed. In contrast, hyperemia did not affect synthase capacity when applied after ischemic preconditioning. Similar effects could be produced in vitro by treatment of heart biopsy samples with anoxia (down-regulation of the ATP synthase) or high-salt or high-pH buffers (up-regulation). We show that both in vitro and in vivo the same close inverse correlation exists between enzyme activity and IF1 content, demonstrating that under all conditions tested the only significant modulator of the enzyme activity was IF1. In addition, both in vivo and in vitro, 1.3-1.4 mol of IF1 was predicted to fully inactivate 1 mol of synthase, thus excluding the existence of significant numbers of non-inhibitory binding sites for IF1 in the F0 sector. 相似文献
83.
Takayuki Nakagomi Toshinori Takagi Mikiya Beppu Shinichi Yoshimura Tomohiro Matsuyama 《World journal of stem cells》2019,11(8):452-463
Ischemic stroke is a critical disease which causes serious neurological functional loss such as paresis. Hope for novel therapies is based on the increasing evidence of the presence of stem cell populations in the central nervous system(CNS) and the development of stem-cell-based therapies for stroke patients. Although mesenchymal stem cells(MSCs) represented initially a promising cell source,only a few transplanted MSCs were present near the injured areas of the CNS.Thus, regional stem cells that are present and/or induced in the CNS may be ideal when considering a treatment following ischemic stroke. In this context, we have recently showed that injury/ischemia-induced neural stem/progenitor cells(i NSPCs) and injury/ischemia-induced multipotent stem cells(i SCs) are present within post-stroke human brains and post-stroke mouse brains. This indicates that i NSPCs/i SCs could be developed for clinical applications treating patients with stroke. The present study introduces the traits of mouse and human i NSPCs,with a focus on the future perspective for CNS regenerative therapies using novel i NSPCs/i SCs. 相似文献
84.
85.
Some effects of fructose-1,6-diphosphate on rat myocardial tissue related to a membrane-stabilizing action 总被引:1,自引:0,他引:1
L Galzigna V Rizzoli M Bianchi M P Rigobello R Scuri 《Cell biochemistry and function》1989,7(2):91-96
This study aims at elucidating the mechanism of action of extracellular fructose-1,6-diphosphate (FDP). FDP is able to inhibit Ca++ entry into the myocardial tissue with an IC50 value of 11.5 mM and in addition, it is bound by rat heart slices, the binding being activated by Zn and conditions of chemical hypoxia induced by KCN and iodoacetate. The overall effect of extracellular FDP includes an increase of frequency and amplitude of contraction of perfused heart at concentration below 1 mM, and, in general, a stimulation of the oxygen consumption of the tissue. The antihaemolytic effect of FDP suggests its action as a membrane stabilizer. The effects of extracellular FDP on the myocardial cell can be interpreted both on the basis of a limited permeability of the cell membrane to it and as a purely extracellular effect transduced through the cell membrane with a final response consisting of an increase in the intracellular FDP. 相似文献
86.
Yeqing Tong Xiaoxu Yin Zhihong Wang Faxian Zhan Yanwei Zhang Jianjun Ye Shuangyi Hou Yijie Geng Yang Li Xuhua Guan Yongzhong Jiang Lingyao Zhang Jifang Dai Katherine A. Mason Jiafa Liu Zuxun Lu Jinquan Cheng 《Gene》2013
Endothelial nitric oxide synthase (eNOS) plays an important role in mediating endothelium-dependent vasodilatation and antithrombotic action and is thus involved in the development of ischemic stroke (IS). Controversial results regarding the association of eNOS gene variable number of tandem repeats (VNTR) polymorphism with IS have been reported by conventional PCR-polyacrylamide gel electrophoresis methods. We aimed to identify any common association of eNOS gene VNTR polymorphism with IS in Chinese Han population by capillary electrophoresis (CE). The VNTR polymorphism of 27 bp within the eNOS intron-4 was determined by CE with specially designed tailed primers in Chinese Han patients with IS (n = 457) and matched elderly controls without IS (n = 457). Significant differences in BMI, WHR, hypertension, diabetes, smoking, TG, HDL, LDL, LDL, and FBG were observed between cases and controls. The distributions of eNOS VNTR polymorphism were not significantly associated with IS after adjustment for cardiovascular risk factors (OR = 1.18, 95% CI: 0.82–1.69). This finding was consistent with the further meta-analysis in Asians. The meta-analysis in Americans demonstrated that 4a/4b + 4a/4a genotype was significantly associated with IS risk with an OR of 1.54 (95% CI, 1.09–2.17) compared with the 4b/4b genotype. Our data suggests that BMI, WHR, hypertension, diabetes, smoking, TG, LDL, and FBG may increase the risk of IS. However, eNOS VNTR polymorphism may be not an independent major contributor for IS in Chinese Han population. The VNTR polymorphism might be associated with IS in Americans based on meta-analysis. 相似文献
87.
Satoshi Okuyama Kana Yamamoto Hirotomo Mori Atsushi Sawamoto Yoshiaki Amakura Morio Yoshimura 《Bioscience, biotechnology, and biochemistry》2018,82(7):1216-1224
Cerebral ischemia/reperfusion is known to induce the generation of reactive oxygen species and inflammatory responses. Numerous studies have demonstrated that naringin (NGIN) has anti-oxidant and anti-inflammatory properties. We previously reported that Citrus kawachiensis contains a large quantity of NGIN in its peel. In the present study, we orally (p.o.) administered dried peel powder of C. kawachiensis to mice of a transient global ischemia model and found in the hippocampus region that it 1) suppressed neuronal cell death, 2) reversed the reduction in the level of phosphorylated calcium-calmodulin-dependent protein kinase II, 3) had the tendency to reverse the reduction in the level of glutathione, and 4) blocked excessive activation of microglia and astrocytes. These results suggested that the dried peel powder of C. kawachiensis had a neuroprotective effect against ischemic brain via anti-oxidative and anti-inflammatory effects. We also showed that these effects of the dried peel powder were more powerful than those obtained with a comparable amount of NGIN alone. 相似文献
88.
Species differences in localization of cardiac cAMP-phosphodiesterase activity: A cytochemical study
L'udmila Okruhlicová Narcisa Tribulová Ján Styk Anita Eckly Claire Lugnier Ján Slezák 《Molecular and cellular biochemistry》1997,173(1-2):183-188
The localization of the membrane-bound cyclic 3,5-AMP phosphodiesterasein cardiac tissues of both, rat and dog was studied by cytochemical method.40 µm thick slices from glutaraldehyde fixed heart tissue wereincubated in the medium with cAMP as a substrate and Pb ions as a capturemetal of the reaction product. The cAMP-PDE activity in the rat ventriclewas only shown positive on the sarcolemma. Whereas, in canine ventriculartissue the cAMP-PDE activity in cardiomyocytes was shown on the sarcolemma,on the junctional sarcoplasmic reticulum and on subsarcolemmal cisternae.The results confirm differences in the localization of cAMP-PDE in dog andrat heart. 相似文献
89.
Fatty acid-binding proteins in the heart 总被引:12,自引:0,他引:12
Schaap Frank G. van der Vusse Ger J. Glatz Jan F.C. 《Molecular and cellular biochemistry》1998,180(1-2):43-51
Long-chain fatty acids are important fuel molecules for the heart, their oxidation in mitochondria providing the bulk of energy required for cardiac functioning. The low solubility of fatty acids in aqueous solutions impairs their cellular transport. However, cardiac tissue contains several proteins capable of binding fatty acids non-covalently. These fatty acid-binding proteins (FABPs) are thought to facilitate both cellular uptake and intracellular transport of fatty acids. The majority of fatty acids taken up by the heart seems to pass the sarcolemma through a carrier-mediated translocation mechanism consisting of one or more membrane-associated FABPs. Intracellular transport of fatty acids towards sites of metabolic conversion is most likely accomplished by cytoplasmic FABPs. In this review, the roles of membrane-associated and cytoplasmic FABPs in cardiac fatty acid metabolism under (patho)physiological circumstances are discussed. 相似文献
90.
Pan Zhang Jingwei Feng Yunjun Liao Junrong Cai Tao Zhou Mingliang Sun Jianhua Gao Kai Gao 《Biochemical and biophysical research communications》2018,495(3):2249-2256