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101.
Rodríguez-Núñez A Cid E Rodríguez-García J Camiña F Rodríguez-Segade S Castro-Gago M 《Journal of child neurology》2001,16(9):704-706
To determine the effects of sepsis on cerebral energy metabolism, the cerebrospinal fluid adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, hypoxanthine, xanthine, and urate concentrations were determined by high-performance liquid chromatography and the neuron-specific enolase levels by means of an enzyme immunoassay method in 32 children with sepsis, without meningitis, aged between 2 months and 13 years, and in 160 age-matched controls. The septic group had significantly higher cerebrospinal fluid concentrations of inosine, adenosine, xanthine, and urate than controls. These results suggest that sepsis could provoke some degree of neuronal hypoxia and significant alterations of cerebral energy metabolism homeostasis. 相似文献
102.
Estradiol enhances endothelial cell interactions with extracellular matrix proteins via an increase in integrin expression and function 总被引:2,自引:0,他引:2
Cid MC Esparza J Schnaper HW Juan M Yague J Grant DS Urbano-Márquez A Hoffman GS Kleinman HK 《Angiogenesis》1999,3(3):271-280
Premenopausal women have a lower cardiovascular risk and a higher incidence of several autoimmune diseases involving blood
vessels than men. Although the precise effects of estrogens on the cardiovascular system are largely unknown, recent data
suggest that estrogens can exert direct regulatory effects on endothelial cells. In the present study, we show that 17β-estradiol
increases human umbilical vein endothelial cell attachment to the extracellular matrix proteins laminin-1, type IV collagen,
type I collagen, and fibronectin. Estradiol enhanced adhesion most significantly to laminin-1 and to fibronectin-derived synthetic
peptides containing an RGD sequence. Upon exposure to estradiol, an increase in β1, α5 and α6 integrin mRNA was observed in
subconfluent cells which was abrogated by treatment with cycloheximide. This increase was followed by a later enhancement
in surface expression of the above integrins. In addition, integrin-mediated signaling was also enhanced by estrogens since
an increase in tyrosine-phosphorylation of focal adhesion kinase induced by cell attachment was observed in estrogen-treated
endothelial cells. Since integrins have an important role in mediating endothelial cell attachment, migration and differentiation,
the increase in integrin expression and function induced by estradiol may be an important mechanism through which estrogens
can promote neovascularization and vessel repair.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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104.
Holzgrabe U Bender W Cid HM Staudt M Pick R Pfletschinger C Balatková E Tränkle C Mohr K 《Pharmaceutica acta Helvetiae》2000,74(2-3):149-155
Ligands for the allosteric site of acetylcholine M2 receptors are able to retard the dissociation of simultaneously bound ligands for the orthosteric site. This effect promotes receptor occupation by the orthosteric ligand. The allosteric effect opens various therapeutic perspectives, e.g., in organophosphorus poisoning. The aim of our studies was to optimize the affinity of the modulators for the common allosteric binding site of muscarinic M2 receptors, the orthosteric site of which was liganded with the N-methylscolopamine. The phthalimido substituted hexane-bisammonium compound W84 served as a starting point. Previous molecular modelling studies revealed two positive charges and two aromatic imides in a sandwich-like arrangement to be essential for a high allosteric potency. A three-dimensional quantitative structure activity relationship (3D QSAR) analysis predicted compounds with substituents of increasing size on the lateral imide moieties to enhance the affinity for the allosteric binding site. Thus, we synthesized and pharmacologically evaluated compounds bearing "saturated" phthalimide moieties as well as phthalimidines with substituents of systematically increasing size in position 3 or on the aromatic ring at one or both ends of the molecule. Within each series, QSAR could be derived: 1. "Saturation" of the aromatic ring of the phthalimide moiety results in less potent compounds. 2. Increasing the size of the substituents in position 3 of the phthalimide enhances the potency. 3. Putting substituents on the aromatic part of the phthalimide increases the potency more effectively: the introduction of a methyl group in position 5 gave a compound with a potency in the nanomolar concentration range which was subsequently developed as the first radioligand for the allosteric binding site. 相似文献
105.
Botero Cid HM Tränkle C Baumann K Pick R Mies-Klomfass E Kostenis E Mohr K Holzgrabe U 《Journal of medicinal chemistry》2000,43(11):2155-2164
Hexane-bisammonium-type compounds containing lateral phthalimide moieties are well-established ligands of the common allosteric binding site of muscarinic M(2) receptors. Previous structure-activity relationships (SAR) revealed two positively charged centers and two lateral phthalimide moieties in a defined arrangement to be essential of a high allosteric potency. The purpose of this study was to replace one carbonyl group of the phthalimides with hydrogens, hydroxy, alkoxy, phenyl, benzyl, and benzylidene groups in order to check the influence of these substituents on the allosteric activity in antagonist-linked receptors. The analysis of the quantitative SAR indicated that a high allosteric potency is related to a certain amount of rigidity as well as polarizibility and the ability to form hydrophobic interactions. 相似文献
106.
1 病例报告 男,7岁.因双下肢不等长,右膝及右踝关节骨性肿大就诊.无明显外伤史,亦无红、肿、热、痛病史.查体:发育正常,营养良好.双下肢不等长,左60cm,右64cm,有跛行.右膝及右踝内侧肿大,肤色正常,关节活动无异常.X线:右侧半身诸关节(肩、肘、腕、髋、膝、踝)骨骺及干骺发育均较左侧增大,肢体较长,骨骺出现亦较对侧提早.如右尺骨茎突骨骺较左侧提早出现(图1).右肘关节肱骨小头骨骺较左侧增大(图2).右髋臼发育浅平,边缘毛糙,右股骨头骨骺较左侧明显增大,其距泪滴之距离较左侧大1.0cm,呈… 相似文献
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