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31.
Glioblastoma multiforme (GBM) cells invade along the existing normal capillaries in brain. Normal capillary endothelial cells function as the blood–brain barrier (BBB) that limits permeability of chemicals into the brain. To investigate whether GBM cells modulate the BBB function of normal endothelial cells, we developed a new in vitro BBB model with primary cultures of rat brain endothelial cells (RBECs), pericytes, and astrocytes. Cells were plated on a membrane with 8 μm pores, either as a monolayer or as a BBB model with triple layer culture. The BBB model consisted of RBEC on the luminal side as a bottom, and pericytes and astrocytes on the abluminal side as a top of the chamber. Human GBM cell line, LN-18 cells, or lung cancer cell line, NCI-H1299 cells, placed on either the RBEC monolayer or the BBB model increased the transendothelial electrical resistance (TEER) values against the model, which peaked within 72 h after the tumor cell application. The TEER value gradually returned to baseline with LN-18 cells, whereas the value quickly dropped to the baseline in 24 h with NCI-H1299 cells. NCI-H1299 cells invaded into the RBEC layer through the membrane, but LN-18 cells did not. Fibroblast growth factor 2 (FGF-2) strengthens the endothelial cell BBB function by increased occludin and ZO-1 expression. In our model, LN-18 and NCI-H1299 cells secreted FGF-2, and a neutralization antibody to FGF-2 inhibited LN-18 cells enhanced BBB function. These results suggest that FGF-2 would be a novel therapeutic target for GBM in the perivascular invasive front.  相似文献   
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Here we attempted to clarify telomere metabolism in parental cells and their derived clonal human induced pluripotent stem cells (iPSCs) at different passages using quantitative fluorescence in situ hybridization (Q-FISH). Our methodology involved estimation of the individual telomere lengths of chromosomal arms in individual cells within each clone in relation to telomere fluorescence units (TFUs) determined by Q-FISH. TFUs were very variable within the same metaphase spread and within the same cell. TFUs of the established iPSCs derived from human amnion (hAM933 iPSCs), expressed as mean values of the median TFUs of 20 karyotypes, were significantly longer than those of the parental cells, although the telomere extension rates varied quite significantly among the clones. Twenty metaphase spreads from hAM933 iPSCs demonstrated no chromosomal instability. The iPSCs established from fetal lung fibroblasts (MRC-5) did not exhibit telomere shortening and chromosomal instability as the number of passages increased. However, the telomeres of other iPSCs derived from MRC-5 became shorter as the number of passages increased, and one (5%) of 20 metaphase spreads showed chromosomal abnormalities including X trisomy at an early stage and all 20 showed abnormalities including X and 12 trisomies at the late stage.  相似文献   
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Sphingomyelins (SMs) and ceramides are known to interact favorably in bilayer membranes. Because ceramide lacks a headgroup that could shield its hydrophobic body from unfavorable interactions with water, accommodation of ceramide under the larger phosphocholine headgroup of SM could contribute to their favorable interactions. To elucidate the role of SM headgroup for SM/ceramide interactions, we explored the effects of reducing the size of the phosphocholine headgroup (removing one, two, or three methyls on the choline moiety, or the choline moiety itself). Using differential scanning calorimetry and fluorescence spectroscopy, we found that the size of the SM headgroup had no marked effect on the thermal stability of ordered domains formed by SM analog/palmitoyl ceramide (PCer) interactions. In more complex bilayers composed of a fluid glycerophospholipid, SM analog, and PCer, the thermal stability and molecular order of the laterally segregated gel domains were roughly identical despite variation in SM headgroup size. We suggest that that the association between PCer and SM analogs was stabilized by ceramide’s aversion for disordered phospholipids, by interfacial hydrogen bonding between PCer and the SM analogs, and by attractive van der Waals’ forces between saturated chains of PCer and SM analogs.  相似文献   
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The acid coagulability of casein from 54 individual human milk samples and the variation of coagulability of their casein preparations by rennin were examined. The casein and whey protein preparations from individual human milk samples were also compared by polyacrylamide gel electrophoresis (PAE). Casein coagulated distinctly from 22 human milk samples when the pH was adjusted to 4.6 with acid, but it did not from other 32 samples. Twenty-two samples of casein preparations coagulated distinctly by rennin in the presence of calcium ions but 19 samples just became turbid. When the classification of human casein based on PAE pattern of major six bands was applied in our preparations, type A appeared most often and type C did least. Any regular relationship was not found between variation of the PAE pattern of casein preparations from individual human milk samples and that of acid coagulability or rennin coagulability.  相似文献   
35.
An abdominal fat accumulation complicated by high blood triglycerides is regarded as a risk factor of metabolic syndrome. Feeding powdered nacre, mother of pearl, from Pinctada maxima, resulted in reduced body weight, visceral fat amount, and blood triglyceride level without influencing the food intake, body length, or amount of muscular tissue, suggesting that nacre powder specifically could decrease visceral fat.  相似文献   
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GABAergic transmission in the amygdala modulates the expression of anxiety. Understanding the interplay between GABAergic transmission and excitatory circuits in the amygdala is, therefore, critical for understanding the neurobiological basis of anxiety. Here, we used a multi-disciplinary approach to demonstrate that GluR5-containing kainate receptors regulate local inhibitory circuits, modulate the excitatory transmission from the basolateral amygdala to the central amygdala, and control behavioral anxiety. Genetic deletion of GluR5 or local injection of a GluR5 antagonist into the basolateral amygdala increases anxiety-like behavior. Activation of GluR5 selectively depolarized inhibitory neurons, thereby increasing GABA release and contributing to tonic GABA current in the basolateral amygdala. The enhanced GABAergic transmission leads to reduced excitatory inputs in the central amygdala. Our results suggest that GluR5 is a key regulator of inhibitory circuits in the amygdala and highlight the potential use of GluR5-specific drugs in the treatment of pathological anxiety.  相似文献   
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