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Carbon monoxide (CO) produces several neurological effects, including cognitive, mood, and behavioral disturbance. Glutamate is thought to play a particularly important role in learning and memory. Thus, the present study was aimed at investigating the local effect of CO on the glutamate level in the hippocampus of mice using in vivo reverse microdialysis. Mice were perfused with Ringer’s solution (control) or CO (60–125?μM) in Ringer’s solution into the hippocampus via microdialysis probe. Dialysate samples were collected every 20?min, and then analyzed with high-performance liquid chromatography coupled to an electrochemical detector. The result revealed that the perfusion with CO had no significant effect on glutamate levels (p?=?0.316) as compared to the control group. This finding does not support a local CO rise as the cause of the increased glutamate level in the hippocampus of mice.  相似文献   
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BACKGROUND: When surgical stress reaches the periosteum, bone resorption and formation that occur as a periosteal response are closely related to angiogenesis and hemodynamics. Thus, we investigated bone remodeling in the healing process after mucoperiosteal flap surgery, focusing our attention on the microcirculation. METHODS: Mucoperiosteal flap surgery was performed on 12 adult beagle dogs. The periosteal vascular plexus was observed on days 7, 14, 21, and 28 after surgery, using three different techniques: in histological specimens into which India ink was injected into blood vessels, under a light microscope; in ultrathin sections, using a transmission electron microscope; and in acryl plastic-injected vascular corrosion cast specimens, under a scanning electron microscope. RESULTS: On day 7 after surgery, the interstitum of the elevated mucoperiosteal vascular plexus was filled with sinusoidal new blood vessels. Bone resorption by osteoclasts was observed around these new blood vessels and many highly permeable fenestrations were present in the vascular endothelium. On day 14 after surgery, sinusoidal new blood vessels were more markedly developed and some regions exhibited glomeruluslike morphology consistent with bone resorption cavities. Activated osteoblasts were present around these new blood vessels and highly permeable vesicles, which were considered to be possible vesiclo-vacuolar organelles (VVOs) and caveolae, were noted in the vascular endothelium. On days 21 and 28 after surgery, the mucoperiosteal vascular plexus was dissected through regression of endothelial cells and fibroblasts and reconstructed into a rough mesh structure, and simultaneously the bone surface became smooth. CONCLUSION: The morphology of the mucoperiosteal vascular plexus changed with bone metabolism and these changes contributed to transport of substances involved in periodontal repair.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - Recently, artificial intelligence has been used to determine sex using fundus photographs alone. We had earlier reported that sex...  相似文献   
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Fibroblast growth factor 23 (FGF23) functions in an endocrine fashion and requires α‐Klotho to exert its effects on the target organs. We have recently demonstrated that the human placenta also expresses α‐Klotho, which led us to hypothesize that FGF23 may exert effects on the placenta. Immunohistochemical analysis demonstrated the expression of FGF receptor 1 (FGFR1) as well as that of α‐Klotho in the feto‐maternal interface of both mouse and human normal‐term placentas, which suggested that these areas might be receptive to FGF23. Therefore, we next investigated whether FGF23 has some roles in the placenta using Hyp mice with high levels of circulating FGF23. Hyp and wild‐type (WT) females were mated with WT males, and the mothers and their male fetuses were analyzed. FGF23 levels in Hyp mothers were elevated. FGF23 levels were about 20‐fold higher in Hyp fetuses than in Hyp mothers, whereas WT fetuses from Hyp mothers exhibited low levels of FGF23, as did fetuses from WT mothers. We analyzed the placental gene expression and found that the expression of Cyp24a1 encoding 25OHD‐24‐hydroxylase, a target gene for FGF23 in the kidney, was increased in the placentas of fetuses from Hyp mothers compared with fetuses from WT mothers. In an organ culture of WT placentas, treatment with plasma from Hyp mothers markedly increased the expression of Cyp24a1, which was abolished by the simultaneous addition of anti‐FGF23 neutralizing antibody. The direct injection of recombinant FGF23 into WT placentas induced the expression of Cyp24a1. The increase in the placental expression of Cyp24a1 in fetuses from Hyp mothers resulted in decreased plasma 25‐hydroxyvitamin D levels. These results suggest that increased levels of circulating FGF23 in pathological conditions such as Hyp mice exerts direct effects on the placenta and affects fetal vitamin D metabolism via the regulation of Cyp24a1 expression. © 2014 American Society for Bone and Mineral Research.  相似文献   
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It has been shown that the stromal-cell population found in bone marrow can be expanded and differentiated into cells with the phenotypes of bone, cartilage, muscle, neural, and fat cells. However, whether mesenchymal stem cells (MSCs) are present in human umbilical-cord blood (UCB) has been the subject of ongoing debate. In this study, we report on a population of fibroblastlike cells derived from the mononuclear fraction of human UCB with osteogenic and adipogenic potential, as well as the presence of a subset of cells that have been maintained in continuous culture for more than 6 months. These cells were found to express CD29, CD44, CD90, CD95, CD105, CD166, and MHC class, but not CD14, CD34, CD40, CD45, CD80, CD86, CD117, CD152, or MHC class II. We also compared gene expression after gene transfer using lenti- and adenoviral vectors carrying the green fluorescence protein to the MSCs derived from UCB because a reliable gene-delivery system is required to transfer target genes into MSCs, which have attracted attention as potential platforms for the systemic delivery of therapeutic genes. The lentiviral vectors can transduce these cells more efficiently than can adenoviral vectors, and we maintained transgene expression for at least 5 weeks. This is the first report showing that UCB-derived MSCs can express exogenous genes by way of a lentivirus vector. These results demonstrate that human UCB is a source of mesenchymal progenitors and may be used in cell transplantation and a wide range of gene-therapy treatments.  相似文献   
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