A novel chiral redox-active ferrocene compound (FcVI) with amphiphilic properties has been synthesized. Cryogenic Transmission Electron Microscopy (cryo-TEM) has been used to estimate the shape and size of the FcVI aggregates in solution. Uni- and multi-lamellar vesicles (between 40 and 300 nm in diameter) were observed in water. Large particles (of more than 1 μm in diameter) with a hexagonal fine structure were found in 50 mM aqueous Na2SO4 solution. Sonication transformed the latter into ‘rosette’-like structures. Cyclic voltammetry has been employed to investigate the electrochemical properties of FcVI. The amphiphile adsorbed on graphite electrodes and a reversible electrochemical behaviour, characteristic of ferrocene, was observed with redox potentials between 330 and 350 mV. 相似文献
Background: Spinal substantia gelatinosa (SG) is a site of action of administered and endogenous opioid agonists and is an important element in the system of antinociception. However, little is known about the types of neurons serving as specific postsynaptic targets for opioid action within the SG. To study the spinal mechanisms of opioidergic analgesia, the authors compared the action of [mu]-opioid agonist [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO) on SG neurons with different intrinsic firing properties.
Methods: Whole cell patch clamp recordings from spinal cord slices of Wistar rats were used to study the sensitivity of SG neurons to DAMGO.
Results: Three groups of neurons with distinct distributions in SG were classified: tonic-, adapting-, and delayed-firing neurons. DAMGO at 1 [mu]m concentration selectively hyperpolarized all tonic-firing neurons tested, whereas none of the adapting- or delayed-firing neurons were affected. The effect of DAMGO on tonic-firing neurons was due to activation of G protein-coupled inward-rectifier K+ conductance, which could be blocked by 500 [mu]m Ba2+ and 500 [mu]m Cs+ but increased by 50 [mu]m baclofen. As a functional consequence of DAMGO action, a majority of tonic-firing neurons changed their pattern of intrinsic firing from tonic to adapting. 相似文献
Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging. 相似文献
Results of treatment of 342 patients with non-parasitic cysts of the liver (NCL) were analyzed. Based on obtained data diagnostic algorithm was developed. Indications and contraindications for transcutaneous and laparoscopic methods in NCL are clarified and substantiated. Features of laparoscopic operations in different location of cysts are presented. In mini-invasive surgeries postoperative complications rate was minimum, there were no lethal outcomes. The authors believe that conventional surgeries in NCL should be performed in critical states only. 相似文献
Based on 102 X-ray and 73 anatomic examinations, the scheme of arterial circulation of the pancreas and spleen, features of their collateral circulation are analyzed. Optimal level of spleen artery ligation at proximal part as the main stage of organ-saving surgical treatment in traumatic disruption of the spleen is substantiated. 相似文献
BACKGROUND: Spinal substantia gelatinosa (SG) is a site of action of administered and endogenous opioid agonists and is an important element in the system of antinociception. However, little is known about the types of neurons serving as specific postsynaptic targets for opioid action within the SG. To study the spinal mechanisms of opioidergic analgesia, the authors compared the action of mu-opioid agonist [D-Ala, N-Me-Phe, Gly-ol]-enkephalin (DAMGO) on SG neurons with different intrinsic firing properties. METHODS: Whole cell patch clamp recordings from spinal cord slices of Wistar rats were used to study the sensitivity of SG neurons to DAMGO. RESULTS: Three groups of neurons with distinct distributions in SG were classified: tonic-, adapting-, and delayed-firing neurons. DAMGO at 1 microm concentration selectively hyperpolarized all tonic-firing neurons tested, whereas none of the adapting- or delayed-firing neurons were affected. The effect of DAMGO on tonic-firing neurons was due to activation of G protein-coupled inward-rectifier K conductance, which could be blocked by 500 microm Ba and 500 microm Cs but increased by 50 microm baclofen. As a functional consequence of DAMGO action, a majority of tonic-firing neurons changed their pattern of intrinsic firing from tonic to adapting. CONCLUSIONS: It is suggested that tonic-firing neurons, presumably functioning as excitatory interneurons, are primary postsynaptic targets for administered and endogenous opioid agonists in spinal SG. Functional transition of cells in this group from tonic to adapting firing mode may represent an important mechanism facilitating opioidergic analgesia. 相似文献
OBJECTIVES: The purposes of this study were to test the hypothesis that vaginal douching is linked to bacterial vaginosis in both symptomatic and asymptomatic women and to identify other demographic, reproductive, and lifestyle factors associated with bacterial vaginosis. METHODS: In this cross-sectional study involving 3 clinic sites, 496 nonpregnant women completed a self-administered questionnaire. Their vaginal smears were assessed and cross-validated for bacterial vaginosis. RESULTS: The prevalence of bacterial vaginosis across clinics ranged from 15% to 30%. In analyses restricted to site 1, adjusted odds ratios (ORs) for bacterial vaginosis remained significant for African American women with 13 or fewer years of education (OR = 5.5, 95% confidence interval [CI] = 2.1, 14.5), hormone use within the past 6 months (OR = 0.5, 95% CI = 0.2, 0.8), and vaginal douching within the past 2 months (OR = 2.9, 95% CI = 1.5, 5.6). CONCLUSIONS: Two lifestyle factors emerge as strongly associated with bacterial vaginosis: systemic contraceptives appear protective, whereas douching is linked to an increase in prevalence. The temporal relationship between douching and bacterial vaginosis needs further clarification. 相似文献