A naturally occurring diamine, cadaverine, and one of its acyl derivatives, monopropionylcadaverine, were tested for their effects on the in vitro release of endogenous dopamine from slices of the rat neostriatum. Dopamine release was allowed to occur spontaneously and was evoked by elevating the potassium concentration in the incubation medium or by electric field stimulation. Monopropionylcadaverine had no effect on spontaneous release of dopamine and little effect on potassium-evoked release of dopamine, but at concentrations as low as 10?8 M in the medium it significantly depressed the electrically induced dopamine release. 相似文献
Attenuated Total Reflectance Fourier Transform Infra Red spectroscopy (ATR FTIR) has been used for surface analysis of powder mixtures. The appearance of one component on the surface of the mixture in greater amounts than that expected from the mass or volume ratio was quantified. Coloured mixtures containing methyl orange were analysed. They contained proportions of components from 0% to 100% in steps of 10%. Mixtures of non-sieved powders of methyl orange and Povidone were dark red when containing only 20% of methyl orange, indicating that particles of methyl orange were present on the surface of the mixture in higher amounts than expected from the mass ratios. Mixtures of methyl orange and Mg stearate, on the other hand, were a light colour, showing the presence of more Mg stearate on the surface than expected. Visual observations correlated with semiquantitative surface concentration determination by ATR FTIR spectroscopy using specific peaks of each component. Quantitative determination of components on the surface of the mixture, using the Beer Lambert law, was possible when characteristic peaks for the first component did not overlap with those of the other component. A non-linear correlation between peak height and concentration of a component in a mixture was explained by distribution of the particle size of components. With a small component, the larger number of particles in the same volume allowed them to surround the larger particles of the second component. These conclusions were confirmed by preparing mixtures with non-coloured components (Povidone-Eudragit, NaCl-Povidone, NaCl-Eudragit. Results again correlated with the ATR FTIR spectroscopy measurements. It was additionally shown that a small proportion of finer particles can drastically influence the surface of powder mixtures, due to their large contribution to the specific surface area. ATR FTIR is thus demonstrated to be a useful method for studying surfaces of powder mixtures also in terms of process analytical technology (PAT). 相似文献
The incidence of antinuclear antibodies (ANA) in asbestos textile workers was compared with the results of HLA typing. HLA B8 antigen was more frequent in the ANA-positive group as compared to the ANA-negative group. The relative risk of this associati-n is 2.77 (p less than 0.02) without correction for the number antigens tested. A decrease in frequency of HLA A10 in workers with ANA was also found. The results suggest that the development of ANA under asbestos hazard may depend on inherited predisposition of which HLA B8 is a marker. 相似文献
Despite a broad range of diagnostic methods, identifying the site of obstruction in the upper respiratory tract in patients with obstructive sleep apnea is not always simple and straightforward. With regard to this problem, we present our observations about the specific shape of the epiglottis in patients with obstruction at the level of the tongue base and/or epiglottis.
Methods
One hundred and forty consecutive drug-induced sleep endoscopy (DISE) video recordings of patients with polygraphy-verified obstructive sleep apnea were analyzed by three independent observers. We compared the levels of obstruction using the VOTE classification and the shape of the epiglottis, both as seen during the DISE investigation and in the awake state. We have calculated the interrater reliability for VOTE classification results and epiglottis shape evaluation by three different observers.
Results
Out of 140 patients, there were 52 (37.1%) with a flat epiglottis. Within this group, there were only 3 (6%) cases in which obstructions at the tongue base and/or epiglottis level were not found. In the group with normally convex and omega-shaped epiglottis, obstruction at the tongue base level was observed in 28 patients (31.8%); obstruction at the epiglottis level was observed in 5 patients (5.7%); and obstruction at both the epiglottis and tongue base level was observed in 3 patients (3.4%). Interrater reliability for VOTE classification was poor for V (ICC?=?0.414) and good for O (ICC?=?0.824), T (ICC?=?0.775), and E (ICC?=?0.852). Additionally, interrater reliability was excellent for epiglottis shape (ICC?=?0.912).
Conclusion
In patients with obstructive sleep apnea, examinations in the awake state and drug-induced sleep endoscopy both showed that in most cases of obstruction at epiglottis and/or tongue base, the epiglottis was flat, i.e., lacking the typical anterior convexity in its upper part. We assume that the change of its shape is a result of degeneration of suspensory apparatus that maintains the shape of the epiglottis and holds it in its position. This could contribute to the better identification of patients with a narrowing at this level, and in turn to better decisions regarding the choice of the most suitable treatment.
AIM: To investigate the pathophysiology of irritable bowel syndrome (IBS) by comparing the global mucosal metabolic profiles of IBS patients with those of healthy controls. METHODS: Fifteen IBS patients fulfilling the Rome Ⅱ criteria, and nine healthy volunteers were included in the study. A combined lipidomics (UPLC/MS) and metabolomics (GC × GC-TOF) approach was used to achieve global metabolic profiles of mucosal biopsies from the ascending colon. RESULTS: Overall, lipid levels were elevated in patients with IBS. The most significant upregulation was seen for pro-inflammatory lysophosphatidylcholines. Other lipid groups that were significantly upregulated in IBS patients were lipotoxic ceramides, glycosphingolipids, and di- and triacylglycerols. Among the metabolites, the cyclic ester 2(3H)-furanone was almost 14-fold upregulated in IBS patients compared to healthy subjects (P = 0.03).CONCLUSION: IBS mucosa is characterised by a distinct pro-inflammatory and lipotoxic metabolic profile.Especially, there was an increase in several lipid species such as lysophospholipids and ceramides. 相似文献