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Cell adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM-1) play an important role in glioma invasion and angiogenesis. The aim of this study was to investigate whether specific genetic polymorphisms of ICAM-1 and PECAM-1 could be associated with glioma development and progression. Single-nucleotide polymorphism in codon 469 of ICAM-1 and codon 125 of PECAM-1 were examined in 158 patients with astrocytomas and 162 controls using polymerase chain reaction and restriction enzyme analysis. The distribution of PECAM-1 polymorphic genotypes in astrocytomas did not show any significant difference. However, a specific ICAM-1 genotype (G/G, corresponding to Lys469Glu) exhibited higher frequency in grade II astrocytomas compared to controls, grade III, and grade IV astrocytomas; suggesting that this polymorphism could be involved in the development of grade II astrocytomas.  相似文献   
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The present work describes the mechanisms involved in the vasorelaxant effect of the diterpene ent-kaur-16-en-19-oic acid (kaurenoic acid). Kaurenoic acid (10, 50 and 100 microM) concentration-dependently inhibited phenylephrine and KCl-induced contraction in either endothelium-intact or -denuded rat aortic rings. Kaurenoic acid also reduced CaCl(2)-induced contraction in Ca(2+)-free solution containing KCl (30 mM). The diterpene did not interfere with Ca(2+) release from intracellular stores mediated by either phenylephrine (1 microM) or caffeine (30 mM). Kaurenoic acid (1-450 microM) concentration dependently relaxed phenylephrine-pre-contracted rings with intact (72.27+/-3.79%) or denuded endothelium (73.28+/-5.91%). The diterpene also relaxed KCl-pre-contracted rings with intact (80.44+/-3.68%) or denuded endothelium (78.12+/-1.26%). Pre-incubation of denuded aortic rings with N(G)-nitro-l-arginine methyl ester (l-NAME, 100 microM), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 1 microM) and 7-nitroindazole (100 microM) reduced kaurenoic acid-induced relaxation (percentage of relaxation: 49.12+/-3.26%, 53.10+/-6.72% and 51.74+/-4.76%, respectively). Indomethacin (10 microM) did not affect kaurenoic acid-induced relaxation. In endothelium-intact rings, 7-nitroindazole and N(pi)-nitro-l-arginine (l-NNA, 100 microM) displaced the curves for the diterpene to the right. Tetraethylammonium (5 mM), 4-amynopiridine (1 mM) and charybdotoxin (0.1 microM) caused a rightward displacement of the concentration-response curve for kaurenoic acid. Conversely, neither apamin (1 microM) nor glibenclamide (3 microM) affected kaurenoic acid-induced relaxation. Collectively, our results provide functional evidence that the effects elicited by kaurenoic acid involve extracellular Ca(2+) influx blocked. Its effects are also partly mediated by the activation of NO-cGMP pathway and the opening of K(+) channels sensitive to charybdotoxin and 4-amynopiridine. Additionally, the activation of the endothelial and neuronal NO synthase isoforms are required for the relaxant effect induced by kaurenoic acid.  相似文献   
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Adult male rats (Wistar lineage) were alcoholized with sugar cane liquor diluted at 30(0) GL during 300 days and sacrificed every 60 days in 5 stages. Samples of choroid plexuses of lateral ventricles were collected and examined at transmission electronic microscope to detect possible ultrastructural alterations and to raise possible pathological correlations. Gradual changes were observed in these animals during all the experiment: dilatation and enlargement of cisternae of Golgi complex, dilatation of RER, presence of digestive vacuoles and a large amount of pinocytic vesicles as well as vesicles with electronlucent content throughout cytoplasm, as well as an enlargement of intercellular space between basolateral interdigitation of the cells and of the connective tissue. The changes observed in the epithelium and connective tissue of choroid plexuses specially in 240 and 300 days of treatment are presumably due to a disturbance in hydroelectrolitic homeostasis, contributing to several morpho-functional disturbs of central nervous system. No changes were observed in the control group animals.  相似文献   
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The vascular effects of two natural occurring diterpenes from the kaurane and pimarane classes were compared. The diterpenes ent-kaur-16-en-19-oic acid (kaurenoic acid; KA) and ent-pimara-8(14), 15-dien-19-oic acid (pimaradienoic acid; PA) were tested for their antispasmodic activity on isolated rat aorta. Vascular reactivity experiments, using standard muscle bath procedures, showed that KA and PA (both at 50 and 100 microM) inhibited phenylephrine and KCl-induced contraction in both endothelium-intact and endothelium-denuded rat aortic rings, with PA being more effective than KA. These compounds also reduced CaCl(2)-induced contraction in Ca(2+)-free solution containing KCl (30 mm). Again, PA produced a greater reduction in CaCl(2)-induced contraction than KA. PA (1-300 microM) and KA (1-450 microM) concentration dependently relaxed endothelium-denuded aortic rings pre-contracted with KCl (maximum relaxation 102.31+/-6.94% and 82.71+/-1.40%, respectively). Similarly, the relaxation induced by KA on aortic rings pre-contracted with phenylephrine (73.06+/-3.68%) was less pronounced than that found for PA (102.21+/-3.64%). Incubation of endothelium-denuded rings for different periods showed that at 50 microM, KA and PA achieved maximum inhibitory activity on KCl-induced contraction after incubation for 60 (53.48+/-5.83%) and 30 min (83.89+/-2.12%), respectively. At 100 microM, KA and PA inhibited KCl-induced contraction, with a maximum after incubation for 30 min (73.58+/-5.30% and 92.07+/-1.20%, respectively). The maximum inhibition induced by PA at both concentrations tested was greater than that induced by KA. The results provide evidence that structural differences between diterpenes, independent of the C-19 carboxylic acid site, influence selectivity for voltage-operated Ca2+ channels and rate of equilibrium with the target site for their vasorelaxant action in rat aortic rings.  相似文献   
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Oral Diseases (2012) 19 , 85–91 Objective: To analyze the expression and distribution patterns of mature dendritic cells (mDCs) and immature DCs (imDCs) in radicular cysts (RCs), dentigerous cysts (DtCs), and keratocystic odontogenic tumors (KCOTs). Materials and methods: Forty‐nine odontogenic cystic lesions (OCLs) (RCs, n = 20; DtCs, n = 15; KCOTs, n = 14) were assessed using the following markers: S100, CD1a and CD207 for imDCs; and CD83 for mDCs. Results: Almost all cases were S100, CD1a, and CD207 positive, whereas 63% were CD83 positive. RCs presented greater number of immunostained cells, followed by DtCs, and KCOTs. The number of S100+ cells was greater than both CD1a+ and CD207+ cells (P < 0.001), which showed approximately similar amounts, followed by lower number of CD83+ cells (P < 0.001) in each OCL type. Different from S100+ cells, both CD1a+ and CD207+ cells on the epithelium (P < 0.05) and CD83+ cells on the capsule (P < 0.05) were preferentially observed. In RCs, significant correlation was found between the thickness epithelium with S100+ and CD1a+ cells, and between the degree of inflammation with CD83+ cells. Conclusions: Dendritic cell populations in OCLs can be phenotypically heterogeneous, and it could represent distinct lineages and/or functional stages. It is suggested that besides DC‐mediated immune cell interactions, DC‐mediated tissue differentiation and maintenance in OCLs should also be considered.  相似文献   
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Clinical Oral Investigations - To evaluate the clinical performance of posterior resin composite restorations regarding experimental and regular adhesive protocols in caries affected-dentin (CAD)....  相似文献   
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