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81.
Purpose: The aim of the paper was to develop the simple procedures for preparation of inclusion complexes of ellagic acid (EA) with cyclodextrins (CDs) and to investigate their antioxidant and antimicrobial activity.

Methods: The structural characterization was carried out using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and nuclear magnetic resonance (NMR) methods. The phase solubility technique was used to investigate the interactions between ‘host’ and ‘guest’ molecules and to estimate the molar ratio between them. The antioxidant and antimicrobial activity of EA and inclusion complexes were determined.

Results: The apparent stability constants were found to be 117?dm3 mol?1 for the complex with β-CD and 161?dm3 mol?1 for the complex with (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD). The results of phase-solubility studies showed that EA formed the inclusion complexes with CDs in the molar ratio of 1:1. The calculated half-maximal inhibitory concentration was 41.18?μg cm?3 for butyl hydroxy toluene, 1.96?μg cm?3 for EA, 0.88?μg cm?3 for inclusion complex with HP-β-CD, and 1.27?μg cm?3 for inclusion complex with β-CD.

Conclusion: The stability constants indicated the rapid release of EA from the inclusion complexes in the aqueous medium at 25?°C. The antioxidant activity of EA was increased, while the antimicrobial activity was preserved after complexation with CDs.  相似文献   

82.
Rapid eye movement (REM) sleep behaviour disorder (RBD) is characterized by dream enactment and REM sleep without atonia. Atonia is evaluated on the basis of visual criteria, but there is a need for more objective, quantitative measurements. We aimed to define and optimize a method for establishing baseline and all other parameters in automatic quantifying submental motor activity during REM sleep. We analysed the electromyographic activity of the submental muscle in polysomnographs of 29 patients with idiopathic RBD (iRBD), 29 controls and 43 Parkinson's (PD) patients. Six adjustable parameters for motor activity were defined. Motor activity was detected and quantified automatically. The optimal parameters for separating RBD patients from controls were investigated by identifying the greatest area under the receiver operating curve from a total of 648 possible combinations. The optimal parameters were validated on PD patients. Automatic baseline estimation improved characterization of atonia during REM sleep, as it eliminates inter/intra‐observer variability and can be standardized across diagnostic centres. We found an optimized method for quantifying motor activity during REM sleep. The method was stable and can be used to differentiate RBD from controls and to quantify motor activity during REM sleep in patients with neurodegeneration. No control had more than 30% of REM sleep with increased motor activity; patients with known RBD had as low activity as 4.5%. We developed and applied a sensitive, quantitative, automatic algorithm to evaluate loss of atonia in RBD patients.  相似文献   
83.
BACKGROUND: The analysis of morphometric right-left symmetry of the salivary glands is important for assessing unilateral changes discovered in these organs during diagnostic imaging. STUDY DESIGN: A study was carried out on 18 adult human autopsy neck and maxillofacial specimens from both sexes (14 males, 4 females), with age range of 17 to 73 years (mean age 49.9 years). The submandibular duct was injected with contrast medium and images were made in two projection planes. RESULTS: Morphometry performed using the obtained radiographs included: (a) caliber (mean proximal, middle, and distal = 1.73 mm, 1.82 mm, and 1.77 mm), (b) length (mean = 37.2 mm); (c) genu of the submandibular duct (mean = 114 degrees ); and (d) longitudinal and transverse diameters of the gland (mean = 44.1 mm and 25.9 mm). Comparison of these morphometric parameters between the right and the left glands revealed no statistically significant differences. CONCLUSION: There is a high level of right-left symmetry in linear morphometric parameters of the submandibular gland.  相似文献   
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Microglia are innate immune cells of myeloid origin that take up residence in the central nervous system (CNS) during embryogenesis. While classically regarded as macrophage-like cells, it is becoming increasingly clear that reactive microglia play more diverse roles in the CNS. Microglial "activation" is often used to refer to a single phenotype; however, in this review we consider that a continuum of microglial activation exists, with phagocytic response (innate activation) at one end and antigen presenting cell function (adaptive activation) at the other. Where activated microglia fall in this spectrum seems to be highly dependent on the type of stimulation provided. We begin by addressing the classical roles of peripheral innate immune cells including macrophages and dendritic cells, which seem to define the edges of this continuum. We then discuss various types of microglial stimulation, including Toll-like receptor engagement by pathogen-associated molecular patterns, microglial challenge with myelin epitopes or Alzheimer's β-amyloid in the presence or absence of CD40L co-stimulation, and Alzheimer disease "immunotherapy". Based on the wide spectrum of stimulus-specific microglial responses, we interpret these cells as immune cells that demonstrate remarkable plasticity following activation. This interpretation has relevance for neurodegenerative/neuroinflammatory diseases where reactive microglia play an etiological role; in particular viral/bacterial encephalitis, multiple sclerosis and Alzheimer disease.  相似文献   
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ABSTRACT: BACKGROUND: The aim of this study was to determine the presence and the intensity of humoral immunity to melanoma-associated antigens: tyrosinase and melanin, in patients with melanoma, in persons with vitiligo and in control healthy people. METHODS: The study involved 63 patients with melanoma and 19 persons with vitiligo. Control group consisted up to 41 healthy volunteers. Mushroom tyrosinase and synthetic melanin were used as the antigens. RESULTS: ELISA test showed significantly (p<0.0000004 and p<0.04) lower levels of IgM anti-tyrosinase autoantibodies, in melanoma and vitiligo patients respectively, compared to controls. Although there was no significant difference between the levels of IgA anti-melanin autoantibodies in melanoma or vitiligo patients in comparison with controls, the enhanced concentrations of anti-melanin IgA autoantibodies were preferentially found in melanoma patients with metastatic disease. Significantly high percentage in the Fc alpha I (CD89) positive cells was determined in melanoma patients (p<0.002 and p<0.008) in comparison to that found in healthy people or in patients with vitiligo, in the already mentioned order, pointing that IgA dependent cellular cytotoxicity is not important for the immune action against melanoma, even more that it is included in some immune suppression. Levels of IgG autoantibodies to mentioned antigens in melanoma patients although low were not significantly lower from controls. These findings analyzed together with the statistically significant low percentage of FcgammaRIII, (CD16) positive immunocompetent cells (p<0.0007 and p<0.003), which was found in patients with melanoma compared with healthy or vitiligo people respectively, and statistically significant low percentage of (CD16+CD56+) natural killer (NK) cells (p<0.005) found in melanoma patients in comparison to healthy controls pointed to the low probability for anti-melanoma IgG mediated, antibody mediated cellular cytotoxicity, (ADCC) and NK cytotoxicity. Moreover the ratio of the percentages of granulocytes and percentage of lymphocytes was statistically higher in patients with melanoma in relation to healthy people as well as to people with vitiligo (p<0.0007 and p<0.05 respectively). CONCLUSION: Autoantibodies to tyrosinase and to melanin which are found even in healthy people, point that consummation of edible mushrooms that carry the antigen tyrosinase and melanin, could influence the humoral anti-melanoma immune response. Levels of different immunoglobulin classes of anti-melanin and anti-tyrosinase antibodies varied depending on the presence and the stage of studied diseases. Besides, the statistically enhanced ratio of the percentages of granulocytes and percentage of lymphocytes, together with statistically decreased percentage of NK cells is found in analyzed melanoma patients.  相似文献   
90.
The aim of this study was to design and optimize a new tablet formulation for treatment of copper deficiency in human organism by using an experimental design. The new no-veneered tablets, prepared by a wet granulation technique, are containg active substance, a copper(II) complex with polysaccharide pullulan. The binder concentration, the disintegrant concentration and the resistance to crushing were used as independent variables in the formulation, while in vitro measured drug release characteristics of the tablets was response variable in a full factorial design 2(3) modeling. A cubic model for data fitted was used to examine the obtained results. They showed that the resistance to crushing has the most significant effect on copper(II) complex release from the formulation, while the disintegrant concentration has smaller influence on dissolution profile of copper(II) complex and the binder concentration had minor impact in this study. Lower value of resistance to crushing has influence on better dissolution profile. Furthermore, physical characteristics of the tablets were evaluated, viz., drug content, hardness, thickness, friability, disintegration time, mass variation, particle size and size distribution.  相似文献   
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